Biostasy

The Theory of Biorhexistasy describes climatic conditions necessary for periods of soil formation (pedogenesis) separated by periods of soil erosion. Proposed by pedologist H. Erhart in 1951, the theory defines two climatic phases: biostasy and rhexistasy.

If I recall, H. Erhart figured this out while on the Congo river contemplating a low sediment load in a high rainfall, potentially highly erosive setting. Impressive. There is a soil science truism that clean water is hungry water, and can't wash across or through the land without taking some with. From a soil scientist's perspective, water is soil in highly dilute form. (So is air.)

Reading between the lines, I don't think Erhart had a research budget much beyond travel expenses. He simply deduced from what he knew of tropical weathering that the river had to be laden with dissolved minerals, calcium especially, washed from the soil by percolating rain water. Groundbreaking as that was in its own right, he didn't stop there. Using induction, he reasoned that when similar conditions dominated it ages past, rivers would have delivered abundant calcium to ancient seas subsequently (at the close of the age, perhaps) yielding vast limestone deposits. He saw these ages as lush, moist, and warm with accelerated chemical weathering accompanied by the formation of deep soils. Biostasy. Between periods of biostasy, he envisioned conditions dominated instead by physical weathering: severe fluctuations in temperature and moisture, sparse vegetation, shallow exposed soils, rivers choked with sediments, but with low solute content. This insight informs interpreting endokarstic sediments(Yves Quinif) in Europe where stalacite formation is observed to be greatest, and with least sediment, during interglacial periods due to higher dissolved calcium content, and less soil erosion.

Simply as a mental exercise, consider a scenario where atmospheric carbon dioxide hits 1200 ppm 200 years from now. In the context of biorhexistasy, what is going to dominate? biostasy, rhexistasy or will it be something well outside H. Erhart's elegant construct? Considering that the Congo and the sediment laden Nile coexist in the same age, it is certainly conceivable that biorhexistasy will continue to play out differently based on location, with neither dominating. But the undeniable effect of higher carbon dioxide is higher chemical weathering. So maybe rhexistasy during the transition, followed by biostasy.

(Recycled from nscss.org)

Garden Char Processing

I've added some photos to Flickr on how I currently prepare my charcoal for add ing to garden soil. This is in support of the Biochar for Gardeners FAQ.

I am lightly soaking (shallow soak, lots of turning to keep surfaces moist) my charcoal to precondition it for a crush-and-chop reduction and then screening. To soak, I add soluble mineral fertilizer and fish emulsion. Once in the soil, these will stimulate biologic conditioning and will help prevent stalled plant growth due to induced N deficiency, a concern with direct use of fresh char in the garden.

Also, regarding the mineral fertilizer, I have it in the back of my mind that adding ammonium sulphate (a common ingredient in off-the-shelf soluble fertilizer formulations) to the soak water will boost water penetration. I am thinking this might help because ammonium sulphate is used hold farm chemicals on waxy plant surfaces (like thistle), and because saltier water generally tends to penetrate further and faster into problem soils. I am encouraged to think that ammonium sulphate helps to overcome fresh charcoal's water repellency, even if only to a slight degree.

Trends in Soil Science Education: Looking Beyond the Number of Students

From swcs.org:

Decreasing student numbers-along with related causes and concerns- is a common topic of discussion in the international soil science community. Such discussion is seldom quantitative. Here we present long-term student numbers (in undergraduate courses as well as MS and PhD graduates) of soil science departments in North America, Europe, and Oceania. A previous study by P. Baveye and co-workers had shown that in the United States and Canada student numbers fell by 40% in more than 80% of the universities between 1992 and 2004. The United States and Canada experienced an increase in female students in soil science between 1992 and 2004. Meanwhile, the number of foreign students has decreased. Student numbers have also decreased in New Zealand. Numbers at Dutch universities decreased in the early 1990s but have since stabilized. Two of three Australian universities had increasing numbers of students for undergraduate courses as well as MS and PhD graduates. Currently in the Netherlands almost half of all MS soil science graduates are female, while in the 1970s and up to the mid-1980s 80% or more of soil science graduates were male. It seems that teaching is becoming more general (more introductory courses to a range of other disciplines), while soil science research is experiencing an opposite trend: specialization. INTERNATIONAL SURVEY

A questionnaire was sent to 43 colleagues at universities in Europe, North America, South America, Africa, and Oceania. We requested long-term data (>25 years) on student numbers between 1980 and 2005. Twelve responses were received.

One of the aims of this research was to quantify trends in student numbers, and it is therefore unfortunate that we were not able to get data from several countries in which soil science is highly important or had made major contributions. For example, no response was obtained from the United Kingdom, where only a few soil science departments have remained; others have closed, have been relabelled, or have been merged with other departments.

It is a tedious job to extract the type of information requested; this may have contributed to the low response rate. In addition, some of those who received the survey might have felt uncomfortable with the results and were not to keen to have them published even though we tried to make it as anonymous as possible. Baveye et al. (2006), who surveyed 61 universities in the United States and Canada, found that some universities could not respond because their legal counsel found it unethical and inappropriate to release information about graduate students.That could be another reason for the limited response in our study.

As only 12 universities responded, the results presented here may not be representative of the whole globe. Here we discuss the main trends and speculate on their possible causes, followed by some discussion on the future of soil science education and student numbers.

STUDENTS IN SOIL SCIENCE

North America

Baveye et al. (2006) surveyed 61 soil science departments in the United States and Canada in 1992 and in again in 2004. The total number of soil science graduates (MS and PhD) in 1992 and 2004 is depicted in figure 1. The number of PhD students decreased (-63%). Of the 36 institutions that responded, 5 universities had increased enrollment, 1 university had constant enrollment, and 30 had decreased enrollment.

A major trend was the increase in the number of female students for both MS and PhD graduates (figure 2).The number of foreigners decreased (figure 3). In 1992, it was found that female students were almost exclusively interested in environmental applications, while male students and students from rural areas were more interested in agricultural issues.

We also received 25 years of student data from a university in the Midwestern United States. Figure 4 presents the number of students in three different courses. The "Soils" course is made of about 10% majors in agronomy, so 90% of the students are outside agronomy and soils. The "Soil Fertility" course is made of majors in agronomy or turf science, and the agronomy major includes those with specific interest in soil science.The "Environmental Quality" course is a general education course; it is within the list of courses that students select to broaden their perspective and to get exposed to environmental issues related to soil. Undergraduate students come from production, business, consulting, plant breeding, and soil and environmental sciences. Some of the production, consulting, and business students may be soil science oriented.

Europe

In the Netherlands, serious soil investigations were started by W.C.H. Staring in the mid-180Os, followed by J. Van Baren in Wageningen, and DJ. Hissink in Groningen in the early 190Os. Soil science rapidly expanded in the mid-1900s with university courses in Amsterdam, Groningen, Utrecht, and Wageningen and the establishment of research institutes (Bouma and Hartemink 2002). After World War II, the number of soil scientists was very large and the knowledge base of Dutch soil science grew enormously. In 1998, there were 23 soil scientists per 100,000 ha (247,000 ac) agricultural land in the Nedierlands compared with 3 in France and Denmark and 6 in the United Kingdom (van Baren et al. 2000).

Currently, soil science is taught at five Dutch universities, although not all have majors in the subject. Enrollment of first year earth science students is depicted in figure 5; these first year students include those who will study geology or petrology. The general trend is that numbers declined from the early 1990s but more or less stabilized since the late 1990s,The number of master's level graduates with a soil science major at Wageningen University is given in figure 6. The number of Dutch master's level students (Ingenieurs [Ir] is the Dutch equivalent of MS) peaked in the mid1990s, decreased, but then had another peak in 2004. The number of foreign MS soil science graduates was around 10 for most of the 1990s.

The most remarkable shift has been in the ratio between male and female soil science graduates (figure 7). Up to the mid-1980s, 80% or more of soil science graduates were men; from then on, the women- to-men ratio increased and has been around 50% to 55% in the past six years (with the exception of 2002). A similar trend, although starting later, happened with the foreign MS students; 70% of soil science graduates in 2005 were female (figure 8).The MS program used to be a two-year program, so there were no graduates every other year from the start of the foreign MS program at Wageningen University in 1972 until it changed to an 18-month program in the 1980s (hence, the gaps in the graph).

The ratio of foreign versus national MS/Ir soil science students is plotted in figure 9. In the 1970s and 1980s, about 40% to 50% of all soil science graduates were foreigners; thereafter, the share of foreigners decreased (except for the year 2000). In the past five years, foreign MS students were less than 40% of all soil science graduates at Wageningen University.

Oceania

Survey responses were received from three universities in Australia and one in New Zealand.

Soil science is taught in 16 universities in Australia. For our study, information on soil science courses and undergraduate, MS, and PhD theses was received from of three universities (in Adelaide, Brisbane, and Sydney).

The University of Adelaide has trained soil scientists since the Waite Agricultural Institute opened in 1924. Since World War II, the university has produced on average at least one graduate in soil science per year at BS honors, MS, and PhD levels. The number of BS honors and PhD graduates has increased since 1995 to about 4 to 5 per year. The number of soil science theses for BS honors, MS, and PhD levels is presented in figure 10.

The number of students attending the "Introductory Soils" and "Soil-Plant Relationships" courses more than halved between 2000 and 2006 at the University of Queensland, Brisbane (figure 11). The trend is comparable to the data from the United States (figure 4), but these are short-term data; longer term data have shown that interannual fluctuation is considerable.

At the University of Sydney, the second year course is an introductory one on soil properties and processes. The third year course is an applied course focusing on soil mapping, soil geography, and environmental issues. The fourth year consists of a large research project and three separate more advanced courses on soil chemistry, soil physics, and pedology. The number of BS students in second and third year soil science courses increased between the early 1990s and 2005. Student numbers in the fourth year is steady. The number of MS and PhD 'graduates has fluctuated considerably in the past two decades, but the number of PhD students is larger now than in the late 1980s and early 1990s (figure 12).

In New Zealand, soil science is taught at six universities. Figure 13 presents data from one university on student enrollment in soil science courses at the second, third, and fourth year. There is a general increase from the early 1980s to a peak in the mid-1990s, after which the numbers in the second and third years decreased to the level of the early 1980s. The large numbers in mid-1990s probably reflect baby boom echo-that is, an overall surge in young people heading to university. The soil science enrollment decline from early 2000s mirrors a decline in enrollment at the whole university. SOIL SCIENCE TRENDS

The main trends include decreasing numbers of soil science students in several parts of the world, a shift in MS/PhD, male/ female, and foreigner/national student ratios, and increased teaching to other disciplines.

Numbers of Soil Science Students

The number of soil science students declined in some but not in all universities, and some differences exist between countries. In the United States and Canada, the number of students decreased by 40% in about 80% of the universities, while in Australia two out of three showed a steady increase in student numbers attending soil science courses and the number of graduates. In a university in New Zealand, the number of soil science students has decreased recently, while in the Netherlands that decrease happened 10 years earlier and student numbers are steady now. Kenya and Tanzania have experienced decreasing numbers as well, despite the importance of agriculture for 80% of the population (Ngugi et al. 2002). Considerable variation was found in the annual number of students attending courses or graduating. The fluctuation in student numbers is partly due to overall university enrollment and number of high school graduates.

In the United States and Canada, the number of soil science PhDs is decreasing relative to the number of MS graduates. In other parts of the world (e.g., the Netherlands and Australia), it is more or less the other way around: fewer students are graduating at the BS honors or MS levels, and the number of PhD graduates in soil science is increasing. In part this has to do with lower increased undergraduate education in the developing world, while students are more likely to go on for doctoral education in Europe and Australia.

If we assume that total number of students has not decreased, then the decline in soil science students is absolute. However, at some universities the decline in soil science student numbers may mirror the decline in overall enrollments. All in all, students seem to prefer other studies (business, law, and medicine), and these are generally viewed as moneymaking degrees.The decline is not unique to soil science but has also occurred in geology, geography, weed science, chemistry (Baveye et al. 2006), and several other disciplines such as physics. In 2003, less than 500 US citizens earned physics PhDs, die lowest number since the early 1960s (Nature, December 1, 2005). Overall, there is a strong growth in information science, medicine, and computer science and little student growth in engineering, mathematics, and physical sciences.

External factors include high school education systems, societal and university changes, and more internal factors such as links to agriculture, the relabelling of the discipline, and "the failure to excite" factor. In many countries, soil science has maintained strong links with agriculture, while the interest in agriculture in the developed world has diminished. That has several causes, including there being enough food but also because there are far fewer farmers and many of them have higher degrees themselves (in the Netherlands, 20% of the farmers have a university or polytechnic degree). In other words, fewer academics are needed in agriculture- so they think.

Other problems start at high school. In the Netherlands, for example, the high school curriculum was rearranged 10 years ago into different profiles.These profiles (e.g., nature and technology, culture and society) contain six to eight fixed subjects and replaced the classic model in which high school students chose their own set of subjects. Now it appears that with certain profiles it is not possible to study soil science. High school students with an interest in physical geography cannot take the profile that contains geography as that profile lacks the subjects necessary to be admitted to a soil science course at a university. A combination of essential science subjects with geography is not possible. So there is a mismatch between what high schools deliver and what universities require, at least for some university soil science courses. Another problem is that many geography teachers at high school are social geographers with little interest or encouragement in physical geography.

National/Foreigner Student Ratios

The share of foreign students is decreasing in the United States and Canada, which is related to the increased difficulties for foreigners to enter the United States (Baveye et al. 2006). In 2001, 200,000 visas were authorized for highly skilled workers, but that had shrunk to 65,000 by 2004. At the American consulate in Chennai, India, the wait to just get a visa interview is more than five months. The United States has always attracted a large number of foreign students and greatly benefited from the import of highly skilled people. According to The Economist (May 6, 2006), 3,000 of the technology firms created in Silicon Valley since the 1980s (that is more than 30% of the total) were founded by entrepreneurs with Indian or Chinese roots. We are not for certain how much the visa restriction and the perceived antagonisms aflfect student mobility and choices, but the Australians, Canadians, and Swiss-countries that are not known to have the same level of obstacles as the United States-have been successful in attracting foreign talent.

Male/Female Student Ratios

Soil science courses and graduations have become increasingly dominated by female students. Clearly, our science is emancipating, and it appears that the encouragement for females to take the science subjects (maths, physics, chemistry) at high schools is starting to pay off. There may also be deeper rooted problems with males at high schools. Several people in the Netherlands suspect that enrollment of males into university is decreasing as they are more likely to fail either at high school or first year at university; females may be better organized, harder working, and stronger in language and nontechnical skills. Another cause could be that soil science is now much more attractive to young women than it was 10 or 20 years ago. In any case, the next generation of soil scientists will be more dominated by women, but that is currently not reflected in leading positions. For example, less than 10% of all International Union of Soil Sciences officers (65 people) in 2006 were women. Articles have been recently published on the achievements of women in soil science in the United States (Levin 2005) and Russia (Prikhod'ko 2006), but little attention has been given to the emerging trends in female students. That will likely change.

Is the current male dominance in soil science (for as long as it takes) an exception? Overall, science is male dominated. In the United Kingdom, for example, less than 4% of tenured physics professors are women (Institute of Physics 2006). Most science department heads are male.

Soils Research Specialization

Highly active university departments routinely attract students as there is an exciting field of research, sufficient funds, and a good research infrastructure for nurturing and educating students and the next generation of scientists. Funding research is a political issue that differs widely between countries (Brumfiel 2006). Globally, three regions take the lead when it comes to funding: United States, Japan, and Western Europe. The United States dominates research funding in the sciences globally, spending almost $145 billion (euro100 billion) on research and development in 2006, more than any other country or region. About 60% of that is defense related. The 25 countries of the European Union spend more than $85 billion (euro59 billion) per year on research. Yet science budgets in the United States, Germany, France, and Japan have been stagnant in recent years. In contrast, scientific research budgets in China have increased by 16% in 2004, in South Korea by 10% in 2005, and in India by 25% recently. The collective research budgets of China, South Korea, and India are less than one-quarter that of the United States, but that will change (Brumfiel 2006). Funding patterns affect scientific disciplines and education; changes in funding amounts and priorities have an impact on everything from the content of university courses offered to the types of employment opportunities that are available for graduates.

In many countries, government funding for soil research has decreased since the 1980s (Hartemink 2002; Mermut and Eswaran 1997; Tinker 1985). In part, this was due to the economic policies of the Thatcher government in the United Kingdom, resulting in privatization and the rule-of-market forces affecting many facets of society including the sciences (Tinker 1985). In part, it was due to the strong link between soil science and agriculture (Baveye et al. 2006).As the interest in agriculture was reduced in much of the developed world (there was ample food, agriculture was perceived to be harmful for the environment), so fell the interest in soil science. The decline in soil science was also due to its inability to cope with the new challenges. Some in the soil science community were split internally about the definition of the kandic or ferralic horizon, and there was a lack of answers for real-word problems or hard data useful for other disciplines. These trends have been observed in many countries, though with some exceptions (Bouma and Hartemink 2002).

Different departments have coped differently with rapid changes in society, and many have relabelled their activities to break away from agriculture or have merged ' with other departments into schools of natural resources or food production. Just like departments of agronomy have been renamed departments of plant or crop and soil sciences (Raun et al. 1998), so have many departments of soil science been renamed in the past century. Table 1 attempts to list some common names of soil science departments in the English- speaking world and how they changed over time. This timeline reflects relabelling but also expansion of the discipline. It is hard to say what is fashionable, but the "Department of Soil and Crop Sciences" is certainly not a popular name at the moment. All in all, it seems that soil is not a too favorable word in the naming of departments; in many cases, it has been replaced by land, earth, or environment. Despite the fact that there are far fewer active soil scientists than two decades ago and that there are fewer soil scientists trained in several parts of the world, the number of soil science publications still increases (Hartemink 2001). Between 1994 and 2006, the number of soil science publications in peer-reviewed journals doubled. No doubt there is some recycling of ideas and dilution of research results over several papers, but the quantity of soil-related publications is an indication that much soil research goes on and there are many global and local issues, now and in the future, to which soil science can contribute (Minasny et al. 2007).

The Aging of Soil Science

Not only are soil science departmental names retiring, so are its people. The aging of the workforce is a common problem in much of the developed world (Lutz and Qiang 2002). The aging of the workforce is noticeable in many departments and soil research centers. Asked what he thought of the 18th World Congress of Soil Science, an Elsevier salesman responded, "Lots of old people, perhaps not a sign of vigorousness" (Philadelphia, July 2006).

We have data on age distribution in the soil science community from the United States, the Netherlands, and Denmark.

In the United States, 44% of the members of the Soil Science Society of America are over 50 years of age and male (figure 14). The older generation is male dominated, while most of the younger members are female.

In 2002, a questionnaire was sent to the 466 members of the Dutch Society of Soil Science. In total 152 people responded (32%). The average age was 52 years and more than 16% of the respondents were above 65 years of age. Only 2% of respondents were younger than 25 years, and 9% reported being between 26 and 35 years old. Student members equalled only 1% (Boshoven and Hartemink 2003).

In Denmark, 50% of Danish Soil Science Society members (70 in total) are over 50 years old, and about one-fifth is between 25 and 40 years of age (O. Borggaard, personal communication, 2007).

The increasing age of soil science society members may be due to (1) the lack of influx from a younger generation, which would indicate a lack of soil science graduates, and/or (2) younger soil scientists not joining learned societies in the same proportions as the previous generation. In any case, the decline in soil science graduates has been a matter of concern and is discussed at soil science meetings and conferences.

CONCLUSIONS

Funding, politics, and the vigorousness of a scientific discipline all affect student numbers. Choices differ greatly between individuals, universities, and nations, but some general principles apply: students are attracted by the vigorousness and chirpiness of a subject (some may call it sexiness) and the possibility of getting a position (perhaps even well paid) after a university degree has been obtained.

The number of publications with hard data on student numbers is limited (it is not good publicity), but there has been some attention to soil science education, particularly in the United States (Baveye et al. 1994), but also in Australia (Smiles et al. 2000), India (Rao et al. 2000), and Africa (Ngugi et al. 2002;Temu et al. 2004).As far as we know, the first paper showing trends in the number soil science students was by Taskey ( 1994), who showed a severe decline in student enrollment from about 170 students in the late 1970s to around 45 in the late 1980s at a university in California.The faculty responded by establishing three new concentrations under the soil science degree program: land resources, environmental management, and environmental science and technology. As a result, soil science enrollment nearly tripled within two years (Taskey 1994).

While our research is specializing with advances in several subdisciplines, our teaching is generalizing: more and more soil science is being taught as part of other science curricula (e.g., ecology). We also see that soil science is being taught by other departments and that soil research is conducted by other disciplines (e.g., geology).

The soil science community should be worried by the declining numbers of soil science students (McBratney 2006).

It is our impression that current soil science graduates have no problems finding employment, and there is a shift from the public to the private sector in job opportunities. But will these trends. continue? What expertise is needed in the near and further future and does our soil science teaching yield capable graduates?

The most difficult task ahead is not to convince policy makers and land users on the need for adequate and up-to-date soil information but to make sure that there are enough young soil scientists equipped with the latest techniques and insights to address future issues. Convincing students that soil science is a valuable study is an important part of that.

ACKNOWLEDGEMENTS

Some of the results in this article were presented at the "Innovation, Speculation and Disneyfication in Soil Science Education" symposium during the 18th World Congress of Soil Science. We are most grateful to David Lowe, Eric Brevik, Oliver Chadwick, Philippe Baveye, Chuck Rice, Neil Menzies, Cameron Grant, Martin Gerzabek, Bern Andeweg, and Marian Bos Boers for digging through university files and providing us with the number soil science students and graduates. Ole Borggaard of the Danish Society of Soil Science and Susan Chapman of the Soil Science Society of America are thanked for the information on the age distribution of their members.

AUTHORS

Alfred E. Hartemink, Alex. McBratney, and Budiman Minasny

REFERENCES

Baveye, P., W.J. Farmer, and T.J. Logan, eds. 1994. Soil Science Education: Philosophy and Perspectives. Madison WI: Soil Science Society of America.

Baveye, P., A.R. Jacobson, S.E. Allaire, J.P. Tandarich, and R.B. Bryant. 2006.Whither goes soil science in the United States and Canada? Soil Science 171:501-518.

Boshoven, E., and A.E. Hartemink. 2003. De NBV enquete. NBV Nieuwsbrief 9:6-10.

Bouma, J., and A.E. Hartemink. 2002. Soil science and society in the Dutch context. Netherlands Journal of Agricultural Science 50:133-140.

Brumfiel, G. 2006. The scientific balance of power-Show us the money. Nature 439:646-647.

Hartemink, A.E. 2001. Look at it this way-Publishing science: past, present and the future. Oudook on Agriculture 30:231-237.

Hartemink, A.E. 2002, Soil science in tropical and temperate regions-Some differences and similarities. Advances in Agronomy 77:269-292.

Institute of physics. 2006. Women in University Physics Departments-A Site Visit Scheme 2003-2005. London: Institute of Physics,

Levin, M.J. 2005. Women in Soil Science (USA). In Encyclopedia of Soils in the Environment, vol. 4, ed. D. Hillel et al., 345-352. Amsterdam: Elsevier.

Lutz, W., and R. Qiang. 2002. Determinants of human population growth. Philosophical Transactions of the Royal Society of London B 357:1197-1210.

McBratney, A.B. 2006. Musings on the future of soil science (in 1k words). In The Future of Soil Science, ed. A.E. Hartemink, 86- 88.Wageningen: International Union of Soil Science.

Mermut, A.R., and H. Eswaran. 1997. Opportunities for soil science in a milieu of reduced funds, Canadian Journal of Soil Science 77:1-7.

Minasny, B., A.E. Hartemink, and A. McBratney. 2007. Soil science and the h index. Scientometrics 73:257-264.

Ngugi, D., A. Isinika, A. Temu, and A. Kitalyi. 2002. Agricultural Education in Kenya and Tanzania (1968-1998). Nairobi: RELMA (Sida).

Prikhod'ko, VE. 2006. Role of women in Russian soil science, Eurasian Soil Science 39:342-343.

Rao, D.R., R.V. Kumari, and E. Haribabu. 2000. Agricultural education in India: A sociological perspective. Oudook on Agriculture 29:177-184.

Raun, WR., N.T. Basta, J.A. Hattey, H. Zhang, and G-V. Johnson. 1998. Changing departmental names from agronomy to plant, crop, and soil sciences. Journal of Natural Resources and Life Sciences Education 27:113-116.

Smiles, D.E., I. White, and CJ. Smith. 2000. Soil science education and society. Soil Science 165:87-97.

Taskey, R.D. 1994. Revision and rescue of an undergraduate soil science program. In Soil Science Education: Philosophy and Perspectives, ed. P. Baveye et al., 21-27. Madison, WI: Soil Science Society of America.

Temu, A.B., S. Chakeredza, K. Mogotsi, D. Munthali, and R. Mulinge, eds. 2004. Rebuilding Africa's Capacity for Agricultural Development: The Role of Tertiary Education. Nairobi: ICRAF.

Tinker, PB. 1985. Soil science in a changing world. Journal of Soil Science 36:1-8.

van Baren, H., A.E. Hartemink, and P.B. Tinker. 2000. 75 years the International Society of Soil Science. Geoderma 96:1-18.

Alfred E. Hartemink is head of the World Soil Museum, ISRIC- World Soil Information, Wageningen, the Netherlands. Alex McBratney and Budiman Minasny are on the faculty of Agriculture, Food and Natural Resources, University of Sydney, Sydney, Australia.

Copyright Soil and Water Conservation Society May/Jun 2008

(c) 2008 Journal of Soil and Water Conservation. Provided by ProQuest Information and Learning. All rights Reserved.

Source: Journal of Soil and Water Conservation

The Charcoal Vision

I want to shout this from the rooftops.

A Win–Win–Win Scenario for Simultaneously Producing Bioenergy, Permanently Sequestering Carbon, while Improving Soil and Water Quality by David A. Laird, USDA-ARS, National Soil Tilth Laboratory

Processing biomass through a distributed network of fast pyrolyzers may be a sustainable platform for producing energy from biomass. Fast pyrolyzers thermally transform biomass into bio-oil, syngas, and charcoal. The syngas could provide the energy needs of the pyrolyzer. Bio-oil is an energy raw material (~17 MJ kg–1) that can be burned to generate heat or shipped to a refinery for processing into transportation fuels. Charcoal could also be used to generate energy; however, application of the charcoal co-product to soils may be key to sustainability. Application of charcoal to soils is hypothesized to increase bioavailable water, build soil organic matter, enhance nutrient cycling, lower bulk density, act as a liming agent, and reduce leaching of pesticides and nutrients to surface and ground water. The half-life of C in soil charcoal is in excess of 1000 yr. Hence, soil-applied charcoal will make both a lasting contribution to soil quality and C in the charcoal will be removed from the atmosphere and sequestered for millennia. Assuming the United States can annually produce 1.1 x 109 Mg of biomass from harvestable forest and crop lands, national implementation of The Charcoal Vision would generate enough bio-oil to displace 1.91 billion barrels of fossil fuel oil per year or about 25% of the current U.S. annual oil consumption. The combined C credit for fossil fuel displacement and permanent sequestration, 363 Tg per year, is 10% of the average annual U.S. emissions of CO2–C.

Soil organisms help ranchers

Intense, low duration grazing builds soil vitality, and increases soil organic matter.

Formulaically, the process described by Manske is very simple; what happens as a result is not.

A rancher chooses three pastures on which to graze the cattle. Starting in the first pasture, the cattle graze for 15 days, and then move on to the next pasture. This is repeated and the cattle find themselves in the third pasture.

Once the cattle leave the first pasture, the soil organisms go to work, converting the organic nitrogen into mineral nitrogen and feeding the plants, building their crude protein.

“Just by changing the management from focusing on dry matter poundage to managing those soil organisms, you can increase the productivity of your land,” Manske said. (Source)

Well observed.

Rhizosperic soil can get awfully puny under long duration grazing. Topsoil pales and topsoil depth is lost, but not to sediment discharge or wind erosion. The in-situ transformation of topsoil to not-topsoil results in the discharge of soil carbon to the atmosphere. The good news is that, unlike wind erosion, water erosion, sheet erosion, or gully erosion erosion, this yet-to-be-named variant of topsoil erosion is reversible.

Redox Cascade

This chart (click for a readable version) shows shows the cascading preference of electron acceptors needed to sustain microbial respiration. When a soil system runs out of oxygen, it relies on nitrate (denitrification) to accept the electrons freed by respiration, and so forth down the cascade. Not shown at the bottom of the cascade is the production of hydrogen from water, but then that is an extreme seldom achieved in nature. The units for Eh are millivolts, the standard measure of redox potential.

An equivalent measure of redox potential is pE. Just as pH is the negative log of the hydrion activity, pE is the negative log of electron activity (source). Soil pE and soil pH are equally important to predicting charge state of metals and nutrients. However, because measuring pH is relatively easier by far, and because knowing pH tells us volumes about expected pE, soil pE is a less discussed subject. It is important to bioremediation, industrial chemistry, and wetland science. Not a household term.

These two are more than a mirror pair, although mirroring is their most notable characteristic. When pH changes, pE must also change in response. The reverse is true also. In soil, that response departs from simple mirroring. So much so that it can seem to be two separate dances.

Soil pH and pE have different causes of change and different effective buffering agents. The term 'buffering' is replaced in a pE context - it is called poise. A stabilized soil pE system is referred to as a well poised system, differences in soil buffering versus soil poise account for the departure from 1:1 mirroring.

Now for the exciting stuff. To many of us, what makes soil different than geologic material is that it is in an excited state, excited mostly by solar energy as facilitated by living processes. Unlike soil pH, soil pE is directly influenced by these energy fluxes.

The most influential cause of changes in soil pE is metabolic respiration aka oxidation. Oxidation doesn't necessarily involve oxygen. Oxidation does necessarily involve shedding an electron. Thus, respiring living systems lower the pE of a soil system, and with pE in the dance lead, pH must follow. Wetlands are low pE systems, wetlands with hydrogen sulphide odors are very low pE systems. Common dryland agricultural crops, like wheat, cannot abide low pE systems. Rice is adapted to low pE conditions.

A well recognized soil buffering agent is lime, which buffers a soil to about pH 8.2. The major agent of soil poise is iron. By all rights, the chart should show iron as having the longest duration horizontal line: there is a vast amount of iron in soil compared to nitrate and manganese. However soil manganese, although far less abundant than iron, plays a more important, more dynamic role in most soil systems.

One soil scientist, Richmond Bartlett, was so taken with the importance of manganese in this regard that he opened his chapter on manganese in a 1995 soil chemistry text (1995, Environmental Soil Chemistry, edited by Don Sparks) with the phrase “We all should fall upon our knees and sing out praise for manganese” Richmond Bartlett goes on to describe the role of manganese in terms that nearly describe a catalyst. Mn is not consumed, and the capacity for metabolic respiration increases in its presence.

This is sheer speculation on my part: from my view through the knothole, the nearly catalytic nature of traces of Mn is a finessing touch that makes bio-char the wonderful soil reef it is. It is a fine point, and one hardly worth mentioning considering the much more important issues that need working out in our pursuit of Wim Sombroek's vision for terra preta nova.

Expanded from information originally posted on the terra preta forum.

Agrichar trials in NSW

News and commentary on agrichar is flowing steadily this spring, first with the reporting on the 1st annual Agrichar Conference, and now with the reporting on initial agrichar trials by the New South Wales Department of Primary Industries (NSW DPI). Particularly encouraging is that the sophistication of the comments continues on the increase.

Snippets from ABC' Discovery channel ...

Recent greenhouse trials found soils mixed with the charred waste, called agrichar or biochar, were more attractive to worms and helpful microbes.

Agrichars trialled by NSW DPI include those from poultry litter, cattle feedlot waste as well as municipal green waste and paper mill sludge. Each agrichar has its own characteristics and interacts differently with different soil types.

Some agrichars raise soil pH at about one-third the rate of lime, raise calcium and reduce aluminium toxicity.

Kimber said more research needs to be done on working out which agrichars are best for which soils and on the impact of any contamination in biomass.

... reinforce the need for local pyrolysis pilot projects. The pyrolysis pilot hurdle is necessary where widespread agrichar use is the goal. Clean air concerns combines with the limited supply of local expertise and experience needed to achieve the low-temperature pyrolysis ideal for producing agrichar.

I have submitted comments emphasizing the need for pilot agrichar projects to our State's climate change folks.

(AP image source)

Biofuel demand pencils out to damaged soil

Crop residue is not a waste. It is a precious commodity and essential to preserving soil quality.

Production systems must be developed so that ethanol produced must be at least C neutral if not C negative. Temptations [to mine soil vitality] aside, biofuels produced from crop residues may neither be free nor cheap.

Rattan Lal, SSSA President, has a timely message to his fellow Society members in the May issue of CSA News (regretfully subscription only). It is that we must take this opportunity to break the cycle of soil destruction that characterizes the rise and fall of civilized man. Biofuels adds unprecedented value to biomass production. Rattan Lal sketches out the numbers, comparing potential demand to crop residue available. With demand tracking above supply, the temptation is to mine the soil of its vitality. Rattan Lal observes that soil exploitation is the primary contributing factor to desertification.

Harvesting crop residues for use as fodder for livestock, residential fuel for cooking and heating, construction material, and other competing uses is a reality in sub-Saharan Africa, South Asia, China, and other developing countries. Therefore, it is not surprising that these are also the regions that have been plagued with severe problems of soil degradation.

With a severe decline in physical quality, degraded soils do not respond to fertilizers even if made available at a subsidized price. Adverse effects of none or low rates of applications of fertilizers and other amendments on agronomic production and soil quality have been exacerbated by the perpetual and indiscriminate removal of crop residues coupled with uncontrolled and excessive communal grazing.

The stubborn trends of low crop yields and perpetual hunger and malnutrition in sub-Saharan Africa and in regions of rainfed agriculture in South Asia cannot be reversed without returning crop residues to the soil and also supplementing them with liberal applications of other biosolids.

Rattan Lal has done an admirable job in this appeal to the his fellow SSSA members. He has included constructive comment on tools and processes available to make biofuels production compatible with maintaining soil vitality. But the undercurrent message is that those of us who love soil must involve ourselves in the process, the policy, and the public discussion of our transition to sustainable energy.

Leave comment or email me if you would like to request a copy of Rattan Lal's May address. Or better yet, join SSSA.

Carbon Sequestration for Farm, Forest Income

The New York Times has an article about selling carbon credit through the Chicago Climate Exchange (CCX).:

An acre of pine forest captures and holds one to two metric tons of carbon dioxide per year, which it uses for photosynthesis. Untilled cropland holds a third of a ton of carbon per acre, and rangeland holds up to a fifth of a ton. The sequestered carbon dioxide is measured by soil tests before and after the planting.

Carbon dioxide credits now sell for about $4 a metric ton. Mandatory restrictions, experts say, could increase the price to $12 or higher. In Europe, the cost of a credit sold for sequestering carbon dioxide has reached $20, and even $30, a ton.

The market for carbon credits seems to hover between $3 and $4. A review of past CCX newsletters reveals sporadic volume, with common fluctuations of $0.50 to $0.75 per metric ton per month. The New York Times article suggests that biological sequestration will ultimately be replaced with geological sequestration. Expectations of sustaining $20 or $30 a ton seem unrealistic.

$3-$4 is far better than the $0.25 that the Confederated Tribes of the Colville Reservation in Washington received for forested land in the 1990s.

The Tri-Societies' science policy blog has a post about Farming Carbon:

Currently, farmers who wish to profit from the sequestration potential of their soils can sell carbon credits on the (CCX).

Science is needed to better quantify the carbon flux and carbon sinks.

At present, aggregators don't attempt to gauge the carbon impact of individual farms nor do they quantify counterbalancing emissions of traces gases. Hopefully, ASA/CSSA/SSSA members can play a constructive role in the CCX, providing the scientific basis on which aggregators will improve their climate accounting.

I would like to see more discussion on the nuts and bolts of accounting and verification.

Flickr Source: George sampling 3/2/07 ESA Common

Agri Char Conference Reviews

Agri-char aka bio-char is the key ingredient in soil scientists' holy grail, terra preta nova (my previous mention). Initial reports from participants at the first meeting of the International Agrichar Initiative indicate continued hope that agrichar amended soils could contribute significantly to our planet's health and productivity.

Kelpie Wilson, Truthout's environment editor, writes:

Charcoal's pores also make excellent habitat for a variety of soil microorganisms and fungi. Think of a coral reef that provides structure and habitat for a bewildering variety of marine species. Charcoal is like a reef on a micro-scale.

Over at the Sydney Peak Oil forum, attendee burko writes:

It would be very easy to become enthusiastic about the future of these integrated technologies. However, there is one overriding impression of this field to keep in mind – it is brand, spanking new. So new that even the choice of name Agrichar is being debated. There are no books; there are few years of experience even amongst the researchers; the debates about the benefits to AGW are only just beginning.

In short, being a part of the conference could be compared to hearing an orchestra tuning up. There are skillful cellists and masterful tuba players preparing next to each other. The idea is potential for beautiful music, rather than cacophony. We aren't really sure who the conductor is yet – plenty of skillful people are taking part of that role. There is cooperation and the desire to share experience at all points – but this is a new kind of orchestra.

While the soil biology alone is a staggering subject, we should be as interested in the methods of producing the black carbon. Burko writes on pyrolysis:

The gas produced is referred to as syn gas, called producer gas sometimes.

My formative understanding of the process says something like this – if you want to produce non-activated chars, temperatures need to be constrained below the levels that gasification requires in order to make the reaction sufficiently exothermic to be self sustaining.

Of course, there is more to it than that – I did find that combustion engineers found it difficult to provide a simpler explanation.

I did get one useful figure from Dr Robert Brown, from Iowa State University – if you're burning wood in an open fire, you're probably only getting a third of the heat energy that should be possible from gasification – a pretty compelling reason to try and understand this stuff. It's been said that up to a third of the worlds deforestation happens in the name of inefficient cooking fires.

From the reports, it is clear that the number of players, and their diversity, is growing exponentially. One reason for this diversity is that the process of making terra preta nova appears to be as adaptable to a wide range of soils and climates as it is scalable. You can have regional collection and distribution approaches coexisting with processes adapted to individual enterprises. The plan at Fourth Corner Nurseries (mentioned previously) near Bellingham, WA is a great example of both points. The operation already amends the soil with char. Observed better root growth confirms what we already sense, that black carbon can have a positive effect on a wide range of soils. The nursery plan to use surplus biomass from their willow coppice field to power the nursery and to produce char is easier said than done, but is brimming with promise.

Image: Scanning electron micrograph of a conductive carbon sticky tab. (Flickr - St Stev)

Review: Soil Health Assessment Training Manual

Cornell’s Soil Health team has completed a final version (”1st edition”) of a comprehensive “Soil Health Assessment Training Manual” (PDF).

At 59 pages, it touches on many areas of interest.

This well organized, and informative, manual has helped warm my still tepid enthusiasm for the soil health assessment movement as well as the closely related soil quality assessment movement.

The soil health assessment movement is a good hearted effort to better understand soil biology and soil function, but it is sabotaged by a dependence on simplistic numeric indexes. Since this could describe the history of the whole of soil science, it seems I have been unfair, condemning the soil health assessment movement in isolation and simply because it is new.

The Manual provides some qualifying documentation that I truly appreciate. The larger list of indices considered and the test locations used for developing the approach are described. This is important information which adds considerably to the value of the Manual. The discussion sections in support of the indicators and in support of the management options are well informed. I am gratified to see that the indices in this manual are much better suited to the challenge of assessing soil health than I have seen in past efforts. Beyond that, I was impressed with how the language used reflects an unfolding understanding of the complex interaction of soil biology, physical characteristics and chemical regimes, especially the forms of carbon involved. I get the distinctive impression that the wording is different than would have been used a year ago, and different than will be used even a year from now. For instance soil fungi is described in terms of thriving in slightly more acidic soil regimes than bacteria. In the past, that distinction would have been left out as inconsequential. In a future soil health assessment, discussion on how to manage soils to enhance beneficial fungi and, later, assessing soils for the presence of beneficial fungi would be natural advancements.

This Manual is a regional and cropping-system specific in nature. It describes "soil constraints and soil quality issues common to soils in New York and the Northeast region, especially in vegetable and field crop production systems." The defined focus frees it from the generalizations that limit broader assessment approaches. At the same time it provides a provides a structure for those interested in applying a soil health assessment approach in other areas.

Users of the Manual send soil samples and data sheets to Cornell's laboratory for analysis and interpretation. The training provided through the Manual is in support of gathering field data and in understanding the resulting report from Cornell.

It will be difficult for self-directed individuals to use the Manual as a resource to delve deeper into some of the assessment techniques. Take for instance, the root health rating. This involves germinating bean seeds in the sampled soil and observing the developed roots for indications of damage by pathogens. No specific references are provided in support of readers seeking to better inform themselves on this approach.

My criticisms of the manual are minor. I highly recommend anybody interested in soil quality, soil health, soil assessment, and soil function download the Manual as a PDF and treat yourselves to at least a quick thumb through.

Blog sources that announced the Manual: Lori Bushway, Molly Day

Soils and its role in a changing climate

Roger Pielke Sr., over at his research group's climate science blog, has been holding forth on land use change and its impacts on long-term near surface temperature. His position is that the role of land use must be further emphasized within the climate change framework. Search for "soil" and "land" for a long list of supporting posts.

This goes beyond deforestation and urban heat islands. Dust and alterations in atmospheric water content play unknown roles and interact with albedo in sometimes counterintuitive ways. For example, irrigation warms rather than cools the land. Evaporative cooling is insufficient to drive net cooling of irrigated regions. Soils darkened by moisture absorb more heat than dry soils and re-radiate more heat during the night. This results in warmer nights and warmer average temperatures.

Current climate models are not sensitive to changes in land use. Neither are they sensitive to the soil's role in affecting atmospheric carbon levels.

Soil organic matter, at roughly 1500 GtC, is the single largest compartment of carbon in the active biogeochemical cycle. At 60 GtC annual flux (in either direction), it is 10 times larger than the 5.5 GtC flux due to burning fossil fuel. Yet soil is the component of the carbon cycle that we know the least about.

Most soil scientists agree with the unvalidated concept that soil carbon levels will likely decline in step with temperature increases. Higher biological activity will result in more decomposition of organic matter. One certainly sees a similar relationship between soil carbon and temperature when comparing the effect of elevation, aspect and latitude. That we have yet to validate it is telling.

Current climate models mostly ignore the specific role that soil microbes play in the release of carbon dioxide into the atmosphere. The information they do include is often based on assumptions that have never been tested in the field, and may be wrong or overly simplistic.

Our climate models are telling us we need to become far more efficient and more conservative in managing our planet's carbon, soil-wise and fuel-wise. But our scientific understanding will never be adequate for crafting our full response to climate change.

The fact is that our climate is infinitely complex. The models climatologists use to predict the future are incredibly sophisticated, yet blunt instruments. Scientists can never account for all the variables involved - indeed, no one has successfully come up with a mathematical equation to describe the formation of a single cloud. And scientists are often woefully out of their depth in the real world. History is littered with lives and regimes that were wrecked when science was allowed to drive policy with no thought to humanity. Tearing down the global carbon-based economy to - in theory - replace it at a later date with unproven and undeveloped technologies would be a similar folly. It is only by tempering science with economics and the market, which is the most efficient arbiter of humanity's wants and needs, that smart climate policy can be made.

Science and the market are partners of longstanding. Economic necessity, as the mother of invention, has been driving the advance of science for as long as science has been an identifiable pursuit.

Distorted Vision
Originally uploaded by uaezlulu.

Technorati Tags: climate+change land irrigation soil+science research politics

Soil Science has Changed

For Carol, over at the Garden Bloggers Book Club, who comments on a previous post:

...be interesting in knowing how soil science has changed in the last 25+ years. I took an introductory class in soil science in 1978 or 79. And I don't recall much discussion about what was living in the soil. Has that become more of an emphasis?

The short answer to that is, yes.

Let's take a bit of a look back to those times. I took my soils classes mostly in 1974 through 1976 at UC Davis. One was a soil microbiology class, and it covered many of the soil-food-web fundamentals that Jeff Lowenfels expands on in "Teaming with Microbes", but it touched only briefly on species interdependence. Ecology was a fairly new field at the time, and much that we know now as soil ecology was just a glimmer in our eyes.

I took an introductory level ecology class in 1973. My recollection was this was only the second year an ecology class was available at UC Davis.

The emphasis in soil microbiology, at the time, was on the metabolic processes the soil biology contributes to nutrient cycling: respiration, immobilization, symbiotic nitrogen fixation, nitrification, ammonification. Carbon:nitrogen ratios of disked in residue were a big deal due to microbial immobilization. There was a strong emphasis on bacteria, and I don't recall anything said about mycorrhizal fungi.

I remember a deep respect for the living component of soil among my pedologic-oriented instructors: "Dirt is soil without life" was drilled into us countless times whenever we slipped up and used the term "dirt" when we should have used "soil".

My edaphic-oriented instructors were not as soil biology oriented. But this was before "soil health" and "soil quality" movements in agricultural soil science became established. It was also before the interest in wetland soil process, bioremediation, protecting groundwater, and understanding why septic systems fail, combined to drive dramatic changes in edaphology.

Edaphology is the study of soil (edaphic) effects. Until about 25 years ago, it mostly synonymous with agricultural soil science as distinguished from pedology, the study of soil in its natural setting. Edaphology now encompasses the new field of environmental soil science, with its more formal emphasis on interdependent living processes in soil.

Soil science has gone through dramatic changes in the last 25+ years.

Picture Source: The Divine Soil
Originally uploaded by Room With A View.

Technorati Tags: soil science history ecology edaphology environment

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The Scoop on Dirt (A Review)

Last September, E/The Environmental Magazine, published The Scoop On Dirt: Why We Should all Worship the Ground We Walk On by Tamsyn Jones. It is beautifully written, but settles into a tired view of soil. As a soil scientist, it irks me that this essay flubs the opportunity to celebrate the unfolding understanding of this dark and patient resource. An expectation of higher aspirations is created by the title and the opening prose.

It’s one of nature’s most perfect contradictions: a substance that is ubiquitous but unseen; humble but essential; surprisingly strong but profoundly fragile. It nurtures life and death; undergirds cities, forests and oceans; and feeds all terrestrial life on Earth. It is a substance few people understand and most take for granted. Yet, it is arguably one of Earth’s most critical natural resources—and humans, quite literally, owe to it their very existence.

From the food we eat to the clothes we wear to the air we breathe, humanity depends upon the dirt beneath our feet. Gardeners understand this intuitively; to them, the saying “cherish the soil” is gospel. But for the better part of society, dirt barely gets a sideways glance. To most, it’s just part of the background, something so obvious it’s ignored.

Even among the environmentally minded, soil sags well below the radar of important causes. But the relationship between soil quality and other aspects of environmental health is intricately entwined. What’s more, it’s a relationship that encompasses a vast swath of territory, from agricultural practices to global climate change, and from the well being of oceans to that of people.

Ultimately it works into a description of Third World soil erosion, chemical burn-out and exhausted productivity. We are told that without aid from the powers that be, the soil, and those it supports, will suffer. I accept that on face value, without hesitation. Third World nations are requesting training in soil management and nutrients to replenish their exhausted soil. We should help them in this.

There is also a short Part II essay, covering factory farms and sustainable farm management. Sidebars provide information on desertification, sludge, the NRCS, soil science as a vanishing skill, and a John Havlin interview.

There is much to like about this piece. Soil seldom gets such professional treatment. However, because it is so well-written – she is a journalist after all – one may not easily spot that some of the observations are presented as foregone conclusions, yet are not supported or warranted. Most of the first 20 paragraphs are full of solum-esque richness. By the end at the 60th paragraph, all the good will banked during the beginning of the essay has been mortgaged by hyperbole...

"Only 8% of our land is arable. This means...", as the context amplifies, that the remaining 92% is "too inhospitable to support our species." (paragraph 8)

"...the practice of destroying soils by torching ... has been employed by armies..." (paragraph 21)

...and mind numbing oversimplification.

"...soils are eroding faster than they can be rebuilt." (paragraph 29)

"The fastest soil regeneration is 200 years, but it can take a million years". (paragraph 30)

The more I learn about soil, the more disservice I see in this type of "Soil Erosion for Dummies" pablum. For one it implies that, absent man's influence, all soils naturally improve with time. Only the young ones do. Nature is not so kind to old soil and soil management must be guided by this fact.

What qualifies as "soil regeneration"? It has always bothered me that regenerating the living processes in the topsoil and regenerating substratum soil mass from the bottom up are treated as not worth differentiating. Still. 80 years, 500-1000 years, or more years to regenerate an inch of soil: You can tell people any number you want, everybody in the know understands its just a theatrical device. A million years is highly theatrical. It implies waiting for a climatic shift or a geologic system reboot.

From a great beginning, the essay wears down to looking at the world through the eyes of a soil science seemingly frozen in time. Conspicuous by its absence are post 1950s discoveries like terra preta and glomalin, discoveries that hint at workings of soil health beyond our current understanding. I choose these examples because they hold the promise of achieving unprecedented soil vitality in the arable soils most of concern in the essay.

Terra preta [updated link (1/29/07)] has been actively researched since the early 1960s. It is a key component of carbon negative fuel production. Terra preta is made by adding charcoal to soil, but total soil carbon continues to build long after additions of charcoal stop. Charcoal producing household wood-gas stoves designs are available. Simple and efficient, these can be used to establish terra preta nova on a scale that matches the Third World's soil carbon crisis. Larger adaptations of the process are being developed commercially. A solar furnace (pdf) alternative is promising.

Glomalin was discovered in 1996. Produced by fungi from carbohydrates supplied by plant allies, glomalin holds 1/3 of global soil carbon, and in a recalcitrant form to boot. It dramatically improves soil health. Low soil nutrient status tends to favor its production, as plants are encouraged to fuel and hydrate their fungal allies in exchange for phosphorus. Perhaps a similar process is supported in terra preta, and accounts for the mysteriously rising tide of soil carbon.

Without a celebration of the ongoing exploration of soil, one is left with the impression that soil scientists have long since exhausted the soil of its potential for significant and exciting discovery.

My final beef is with the John Havlin interview. Why do our soil science leaders continue to get sucked into overplaying the agriculture card? Maybe Charles Kellog should have pounded SSSA a little harder back when he had a chance.

"Many people have the vague notion that soil science is merely a phase of agronomy and deals only with practical soil management for field crops. Whether we like it or not this is the image many have of us." Charles E. Kellog, A challenge to American soil scientists: On the occasion of the 25th anniversary of the Soil Science Society of America. Soil Science Society of America Proceedings, 25(6):419-423, 1961.

Technorati Tags: environment erosion news soil science

Gold, Green Roads to OA Soil Science Research

You invest your limited time in reading this and similar science themed blogs to inform yourself. You pursue links that promises to ground you in a new understanding. All too often your admirable efforts are frustrated by links to restricted fee-for-access login pages.

What purpose does it serve to so restrict knowledge that was funded in the public interest? A growing number of open access vehicles for publication and peer review indicate that restricted access is a waning model for funding and disseminating scientific knowledge. OA models are working for chemistry, physics and internal medicine. They will work well for the other sciences.

A recurring theme of advocacy on this blog is open access (OA) to soil science research articles. While I believe strongly that all soil scientists should support their professional soils organizations financially, I believe as strongly that all published soil science research should be freely accessible on the web. Those that can best capitalize on soil science are least able to afford fee-based access. The readers of this blog need OA soil science sources. I am committed to delivering these up to you in the several forms available: gold road and green road.

Advocates of OA differentiate between a "gold road" and a "green road" to success. The gold road is when journals move from restricted access to open access. Without fanfare, the SSSAJ has stepped out onto the gold road. SSSAJ articles now convert to unrestricted access after an 18 month embargo. As a member of SSSA, with a paid subscription to SSSAJ since 1976, my regard for and commitment to SSSAJ has risen to new heights on this quiet action.

SSSAJ's most recent un-embargoed articles are in Vol. 69, Iss. 4.

The green road to OA is where authors self-publish research in open access venues. Especially significant to this is self-archiving. Because it is a seamless extension of accepted pre-web-era practice, OA self-archiving does not interfere with copyright and publication by scientific journals. Because of this acceptance and the unassailable viability of OA self-archiving, resistance is futile:

Open Access (OA) means free access for all would-be users webwide to all articles published in all peer-reviewed research journals across all scholarly and scientific disciplines. 100% OA is optimal for research, researchers, their institutions, and their funders because it maximizes research access and usage. It is also 100% feasible: authors just need to deposit ("self-archive") their articles on their own institutional websites. Hence 100% OA is inevitable. Yet the few keystrokes needed to reach it have been paralyzed for a decade by a seemingly endless series of phobias (about everything from piracy and plagiarism to posterity and priorities), each easily shown to be groundless, yet persistent and recurring. The cure for this "Zeno's Paralysis" is for researchers' institutions and funders to mandate the keystrokes, just as they already mandate publishing, and for the very same reason: to maximize research usage, impact and progress. 95% of researchers have said they would comply with a self-archiving mandate; 93% of journals have already given self-archiving their blessing.

I have linked to self-archived sources in several posts. Philippe Baveye passed along his Whither Goes Soil Science..., which I archived with PB's permission on the nscss.org site. It's a revealing article, and gets linked frequently. Bestenergies.com's copy of the Nature article on Terra Preta (pdf) appears to be based on a similar self-archiving arrangement. Links to self-archived articles were provided in the post on invasive earthworms. In this last case the counter-intuitive conclusion of the research, that the need to prevent the spread of invasive earthworm calls for state legislative action, likely gave the authors critical incentive to make their work more widely accessible to lawmakers and the affected public.

My position is that if a source I here use is restricted access, I won't frustrate you by linking to it. And if I can't link to it, I won't rely on it to explain the positions I take.

I am curious if anybody else reading this blog has thoughts on OA, and especially as it relates to soil science. Your comments are strongly encouraged.

---

Special thanks to Peter Suber, for his Open Acess News Blog, the best place to monitor the ever strengthening pulse of OA, and the source of my exposure to Zeno's Paralysis.

Photo source: Road through the green
Originally uploaded by chartno3.

Tech Tags: blog open access research soil science

Sombroek's Challenge - Terra Preta Nova

The Godfather of Terra Preta, soil scientist Wim Sombroek (1934 - 2003) enjoyed a lifelong fascination with enhanced soil. The importance of plaggen soil in his native Netherlands impressed him at an early age, and early in the 1960's, he recognized in the Amazonian Dark Earths something familiar and precious. Before his passing, he assembled specific soil scientists, challenging them to discover the process for making and sustaining a modern equivalent of the bio-char enhanced terra preta, what he termed terra preta nova.

A great opportunity in answering Sombroek's challenge lies is surmounting the opacity of mutualistic rhizospheric species to traditional analytical approaches: only 1% of rhizospheric species are cultureable ala petri dish. We don't have a robust body of culture-independent studies against which to compare Terra Preta, so we are doubly challenged to reverse-engineer the phenomenon.

Considering Wim Somboek's many noteworthy accomplishments, the perspective of his international leadership, and the late-in-life timing of his challenge, one senses he is pointing us to a mystery fundamental to understanding soil in new and exciting ways. This happens at a time when the soil science profession is in dynamic transition and sorely in need of a unifying vision. Wim Sombroek has given soil scientists a most welcome and worthy quest.

Tech Tags: microbiology research soil science soil scientist terra preta

Black Earth

Peak Energy has a long post on Terra Preta that brings together what has been established on the subject. As of yet, there is no direct mention of the role of glomalin , just a minor mention of the mutualistic fungi that produce it. Glomalin is an unvalidated factor in Terra Preta formation that several of us sense will be demonstrated by soil research as fundamentally important.

Spurred on by back40, I am fascinated with bio-char, Terra Preta's key soil amendment. Last summer I constructed a small charcoal retort out of a cracker tin. I used it to produce small pilot batches of low temperature charcoal. Hoping to transform my simple charcoal into a reasonably bio-char-like material, I am currently composting my bits.

Image source: Nestor Kaempf

Tech Tags: terra preta bio-char glomalin blog

Two New Soil Science Blogs

David Crouse, over at North Carolina State has started a new soil science blog. It is obviously a tentative effort at this point, seeing as how the last post has nothing to do with soil science. You have to start somewhere. I am eagerly looking for more soil science blogging. NC State is one of my favorite soil science universities so, while I haven't met DC personally, I expect this blog could work up to (or inspire) something noteworthy.

I have started a second soil science related blog: NSCSS News and Views. A fair amount of material gets passed to me as NSCSS Secretary. Job opportunities, for example. I'll post items as they get to me. If I notice anything attracting and holding folks attention, I'll build on that.

See also: Where are all the soil science bloggers....

Tech Tags: soil science, news, blog

NC Science Blogging Conference Jan 20, 2007

The world needs more science bloggers.[1] There are a lot of science bloggers in NC.[2] Soil science bloggers are few.[3] There is a concentration of soil scientists in and very close to North Carolina.[4] Soil scientists should go to the 2007 Science Blogging Conference Sat, Jan 20, 2007, 8:30 a.m. to 5 p.m. Chapel Hill, NC.[5]

.......