A recent toast to James Watson highlights a tolerance for bigotry many want excised from the scientific community.
Excavating existing topsoil and adding donor soil, researchers revitalized degraded farmland in the span of six years.
July 11, 2016|
E.R.J. WUBSDonor-soil microbes drive—and can speed up—the restoration of degraded farmland, scientists at the Netherlands Institute of Ecology in Wageningen have shown. The results of a six-year field test, published today (July 11) in Nature Plants, show the greatest ecosystem repair in formerly arable fields in which the team removed a thick layer of existing topsoil before applying a thin layer of microbe-rich donor soil.
“Of course, seeds of plants were also present in the donor soil,” study coauthor Jasper Wubs of the Netherlands Institute of Ecology told reporters during a press briefing. “But our study shows that it is in fact the soil organisms—such as the bacteria, fungi, and roundworms—which determine the direction of ecosystem restoration.”
Wubs and colleagues tested various soil inoculation approaches in plots carved from a 160-hectare field in Reijerscamp, the Netherlands, that had been farmed for nearly 60 years. In control plots, the researchers left the land as it was. In experimental plots, they left behind existing topsoil or removed up to 50 cm before spreading a 1 cm-thick layer of donor-grassland or -heathland soil. While all the plots that received donor soil fared better than the control plots, the donor-soil–recipient plots in which existing topsoil had been excavated prior to inoculation showed more improvement, and faster too.
The researchers also reported that the type of donor soil drove the resulting microbial community’s composition toward that of the donor site—either grass or heathland. “This is similar . . . to the use of fecal transplants to restore disrupted gut microbiomes in humans,” said Wubs.
“This is pretty cutting-edge research,” said Neiunna Reed-Jones, a fellow at the Oak Ridge Institute for Science and Education who studied enteric human pathogens in agricultural environments while a postdoc at the University of Maryland. While the approach has been discussed in the literature, “I hadn’t heard of anyone doing soil transplantation before.”
“Biocontrol, plant growth promotion, and nutrition by microbial inoculants have a long tradition in agriculture,” noted Gabriele Berg of the Graz University of Technology in Austria who was not involved in the work. “Therefore it is not surprising that . . . soil transfer works well.”
While the study provides an important proof of concept, Berg would like more details on the mechanisms of action. “For me, the most important fact is to understand the quality of soil, especially the microbiota,” she wrote in an email to The Scientist. “To work with a ‘black box’ of soil, which contain thousands of different microbial species, is difficult and not up-to-date.”
Both Berg and Reed-Jones questioned whether the soil-inoculation approach might transfer potentially harmful microbes along with the beneficial ones. “We have to consider that each soil contains a lot of plant and potentially human pathogens,” wrote Berg.
“Will this soil inoculation cause any destruction to already-established soil communities?” asked Reed-Jones. “If this was taken on a larger scale, transplanting soil to a different area, would that introduce new soil microbiota and would they start competing? Would that competition allow some other soil disease to occur?”
Still, the approach shows promise for agriculture. Through microbial transplantation, “enriching soils that may be not be very productive . . . may help with plant proliferation, nutrient management, and carbon fixation,” Reed-Jones said.
E.R.J. Wubs et al., “Soil inoculation steers restoration of terrestrial ecosystems,” Nature Plants, doi:10.1038/nplants.2016.107, 2016.
July 12, 2016
Soil innoculation has been done for a long time. Reclamation of oil field soils and other reclamation sites using manure,... has been done. I've promoted that for a couple decades now. Its not new using microbes to regenerate soil and get back a decent ecosystem.
My company has been promoting using Little River Pond Mill remediated livestock waste on land for over 30 years. What was found in compacted zero til soils about 2 decades ago now was that it promoted a renewal of the soil and eliminated the compaction. Its simple microbiology and soil science.
Sorry folks - nothing new here.
Its another research study confirming what we already know about soil microbes - they are essential for plant growth and soil renewal/regeneration/stabilization. Its why I went from Horticulture, to Plant Ecology/Plant Science/Microbiology, and then Soil Science for my degrees.
There are a lot of microbial mixes used for reclamation purposes and one of the things I stress is to use indigenous microbes instead of introduced species. Unfortunately my words have fallen on deaf ears in many cases - seems that many of the microbial suppliers prefer to have a patented approach rather than an ecosystem approach to reclamation.
July 13, 2016
An excellent support for the functional concept of holistic community ecology.
This research opens many diverse approaches.
July 13, 2016
Acorns only grow well when germinated in decomposing oak leaves or near existing oaks. Soils supporting desired plants already have the desired microbes and need to be cultivated in the soils for those plants to thrive elsewhere. While this is widely known, the principle of "feeding the soil microbes that feed the plants" has come to the forefront of organic gardening. Microbes unlock minerals to feed plants, and the plants in turn provide carbon for the microbes. The biomass of the mycillia can extend the water and nutrient uptake by 3x by being physically intertwined within the cells of the root mass. Apparently a variety of microbes work togeather to accomplish various stages like white rot that digests lignin freeing up hemicellulose for microbial digestion by something else. There is much more going on with this that we could apply if we understood it better. Terra prety for example; https://en.wikipedia.org/wiki/Terra_preta
July 13, 2016
Simple is a relative term. People don't know what has been done or what it could mean to them. This TED talk discusses how microbes clean oil from soil and more; https://www.ted.com/talks/paul_stamets_on_6_ways_mushrooms_can_save_the_world?language=en
July 15, 2016
The quoted criticism is nonsense. Typical sanctimonious pseudo-science to complain about practical measures vs. theoretical and impossible perfectionism. What is wrong with using healthy donor soil to innoculate unhealthy soil/environment? Should first wait until you have characterized all the microbes in the donor soil in relation to known pathogens (an unknown?) when in fact it is communities/ensemble of microbes that are typically responsible for effects not the presence or absence of a particular species.
October 14, 2016
I first used "soil inoculation" in 1972. I was active until 2000 when I thought I had sold my consulting business to a newly-minted PhD ecologist. Please advise about earlier projects.
I do not consider bs or any other fertilizer desirable in ecosystem restoration. I would be delighted to be corrected by the evidence.
Indigenous microbes, si! Non-indigenous microbes, no!
I look forward to being corrected by anybody, including the vast multitudes of folks superior to me.