Soil Organic Matter, Soil Structure, and Bacterial Community Structure in a Post-Agricultural Landscape

Converting forest and wetland landscapes to agriculture has shown result in a loss of organic matter, structure, microbial diversity the converted soil but recovery post-agricultural soils remains poorly understood. Here we coupled landscape-scale surveys 1) carbon nitrogen levels, 2) aggregation, 3) bacterial metagenomes investigate after 30 years sites with ranging from well drained drained. Sites no evidence past (Reference) served as endpoints. A secondary aim evaluated role nitrogen-fixing symbiosis, here associated alder ( Alnus incana ) trees, restoration. Soil levels restored (3.5%) were comparable present-day farm (3.4%) much lower than Reference (>7.3%). The same trend occurred levels. trees had more acidic pH values. Alder promoted structure macroaggregates being largest fraction bulk (75%). Natural abundance stable isotopes suggested extensive decay matter within aggregates. Comparison total reads indicated community sites, except for well-drained alder. Dissimilarity among terms gene abundances metabolism, membrane transport, genetic repair pathways. is slow when caused large case our study, changed markedly, it did study. However, fairly rapid noted promising, now need better understanding plant species that improve restoration both soils.