Wednesday, October 15, 2008

Is there a soil biology “cell” in the GRDC?

A recent tender document reveals that the ‘biology’ bug has bitten someone inside the GRDC.
Without once using the word “biology”, the GRDC tender specifies a biological approach, which it terms ‘novel’ to refer to Mother Nature’s oldest soil technology: “Novel approaches to making fixed soil P available to plants are required, as are practical means of increasing crop uptake of the P present in some sub-soils... Typically 60-80% of the fertiliser P applied to crops becomes ‘fixed’ and unavailable for plant uptake. Plant P uptake can be affected by mechanisms in the plant itself and by processes in the rhizosphere.”
“Proposals should also consider the role of soil pools in N availability (including non-symbiotic N fixation)… Work is also sought… to examine the practicality and economic feasibility of novel sources of nutrients for broadacre cropping. The outputs from this component of the program must include practical measures that growers can use to optimise nutrient cycling and availability within the soil profile and its nutrient pools and stores.”
The GRDC is best known to us as the lead institution in the National Campaign to Deny Soil Carbon Sequestration in Australian Soils At Any Cost and With Any Argument. Readers might recall the “Australian soils too ancient and degraded to sequester significant amounts of carbon” argument. In fact, it is still being recited at seminars and conferences, despite being dismissed by leading soil scientists as “nonsense”. The new line of attack features the assertion that it is too costly to grow humus because you have to add nitrogen, phosphorus and sulphur, and these elements are more expensive than the return in soil carbon credits. This argument proved to be a defining moment in the debate because it revealed the gap between soilies that ignore biology, and those who focus on microbiology (with the danger that they can drift off into a soil mysticism a la Steiner).

Try Biology?

The current rush to “Try Biology” is sweeping up scientists, soils extension people and research institutions. Sydney University’s Soil Science Department is advertising for a senior lecturer in soil microbiology. Soil-Bio has been declared ‘the new frontier of soil science’ by one senior scientist.

Dr Elaine Ingham and Dr Christine Jones (both working outside the mainstream) deserve credit for raising the profile of the applied science of soil biology in Australia. Dr Ingham is responsible for the formation of Microscope Clubs among farmers in the Central West of NSW and beyond. For many years, soils officers dismissed microbial inoculation as ‘witches brew’. But farmers perservered. Now we know that a new paradigm of soil dynamics is made possible by harnessing the microbial workforce around the roots and giving these workers the tools they needs to perform miracles in plant nutrient availability and carbon storage.

Soil biology provides the answer the conundrum: where does the C come from if outputs equal inputs? And, where does the N, P and S come from? Probiotic inoculants and soil treatments are recording extraordinary levels of carbon, nitrogen, and phosphorus performance in field trials. Naturally they won’t be believed until the findings have been reproduced and subjected to peer review. (Both are major hurdles: 1. Science has yet to reproduce on-farm results with grazing management, largely due to methodological problems associated with studying an holistic ‘ecological’ phenomenon. There is controversy inside the scientific community about reductionism - studying a single organism in isolation - and holism - studying the organism as part of a system. 2. Even if the phenomenon can be reproduced, the results may not be believed. There is no observation without interpretation. The “Theory-Laden Observation” is a condition that scientists who study the process of scientific practice have identified. It means that what scientists observe is a function of the theories they believe in, that even the language used determines outcomes. For instance, words like ‘atom’ and ‘current’ presuppose a particular theory of matter. "Wave" and "Packet" imply another. In soil C science, the use of the words “inputs” and “outputs” implies a balance within a closed system. It says, “What else is there?” So soil biology’s prodigious potential may never get the official tick. But that hasn’t stopped grazing management or pasture cropping. (BTW, a university scientist conducting a sampling exercise for one soil inoculant user threw the first round samples and results away recently because they were “too high”. Coalition members report similar experiences. "There must be something wrong with the sample" is a normal first response.)

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