title: How does conversion of natural tropical rainforest ecosystems affect soil bacterial and fungal communities in the Nile river watershed of Uganda?
abstract: Uganda's forests are globally important for their conservation values but are under pressure from increasing human population and consumption. In this study, we examine how conversion of natural forest affects soil bacterial and fungal communities. Comparisons in paired natural forest and human-converted sites among four locations indicated that natural forest soils consistently had higher pH, organic carbon, nitrogen, and calcium, although variation among sites was large. Despite these differences, no effect on the diversity of dominant taxa for either bacterial or fungal communities was detected, using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Composition of fungal communities did generally appear different in converted sites, but surprisingly, we did not observe a consistent pattern among sites. The spatial distribution of some taxa and community composition was associated with soil pH, organic carbon, phosphorus and sodium, suggesting that changes in soil communities were nuanced and require more robust metagenomic methods to understand the various components of the community. Given the close geographic proximity of the paired sampling sites, the similarity between natural and converted sites might be due to continued dispersal between treatments. Fungal communities showed greater environmental differentiation than bacterial communities, particularly according to soil pH. We detected biotic homogenization in converted ecosystems and substantial contribution of β-diversity to total diversity, indicating considerable geographic structure in soil biota in these forest communities. Overall, our results suggest that soil microbial communities are relatively resilient to forest conversion and despite a substantial and consistent change in the soil environment, the effects of conversion differed widely among sites. The substantial difference in soil chemistry, with generally lower nutrient quantity in converted sites, does bring into question, how long this resilience will last.
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden (XTBG), Chinese Academy of Sciences, Kunming, Yunnan, P. R. China; University of the Chinese Academy of Sciences, Beijing, P. R. China; Great Nile Conservation Centre (GNCC), Lira, Uganda; Institute of Tropical Forest Conservation (ITFC), Mbarara University of Science and Technology (MUST), Kabale, Uganda.
authors.forename: Peter O
authors.initials: PO
authors.lastname: Alele
authors.affiliation: Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway; Center for International Forestry Research (CIFOR), Bogor, Indonesia; Department of Ecology and Natural Resource Management, School of Environment, Science and Engineering, Southern Cross University, Lismore, New South Wales, Australia; Institute of Tropical Forest Conservation (ITFC), Mbarara University of Science and Technology (MUST), Kabale, Uganda.
authors.forename: Douglas
authors.initials: D
authors.lastname: Sheil
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden (XTBG), Chinese Academy of Sciences, Kunming, Yunnan, P. R. China.
authors.forename: Yann
authors.initials: Y
authors.lastname: Surget-Groba
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden (XTBG), Chinese Academy of Sciences, Kunming, Yunnan, P. R. China; University of the Chinese Academy of Sciences, Beijing, P. R. China.
authors.forename: Shi
authors.initials: S
authors.lastname: Lingling
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden (XTBG), Chinese Academy of Sciences, Kunming, Yunnan, P. R. China; Texas Tech University, Lubbock, Texas, United States of America.
authors.forename: Charles H
authors.initials: CH
authors.lastname: Cannon
mesh_terms: D001419:Bacteria / Q000145:classification / Q000302:isolation & purification; D044822:Biodiversity; D002118:Calcium / Q000032:analysis; D002244:Carbon / Q000032:analysis; D003247:Conservation of Natural Resources / Q000379:methods*; D004269:DNA, Bacterial / Q000235:genetics; D005658:Fungi / Q000145:classification / Q000302:isolation & purification; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009584:Nitrogen / Q000032:analysis; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D065947:Rainforest; D045483:Rivers / Q000382:microbiology; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D014454:Uganda
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D012987:Soil; D002244:Carbon; D009584:Nitrogen; D002118:Calcium