1,721,043 research outputs found
Landscape Assessment (B08): Water content of litter and soil 0-10 cm
No full textWater content of litter and soil (0-10 cm) were determined gravimetricall
Landscape Assessment (EFForTS - B08) pH of litter and soil 0-10 cm
No full textLandscape Assessment sampling 2021, Sumatra, Indonesia
pH (H2O) of litter and soil (0-10 cm) were measured using a digital pH meter (Hanna 208
How does litter quality affect the community of soil protists (testate amoebae) of tropical montane rainforests?
No full textLitter quality and diversity are major factors structuring decomposer communities. However, little is known on the relationship between litter quality and the community structure of soil protists in tropical forests. We analyzed the diversity, density, and community structure of a major group of soil protists of tropical montane rainforests, that is, testate amoebae. Litterbags containing pure and mixed litter of two abundant tree species at the study sites (Graffenrieda emarginata and Purdiaea nutans) differing in nitrogen concentrations were exposed in the field for 12 similar to months. The density and diversity of testate amoebae were higher in the nitrogen-rich Graffenrieda litter suggesting that nitrogen functions as an important driving factor for soil protist communities. No additive effects of litter mixing were found, rather density of testate amoebae was reduced in litter mixtures as compared to litterbags with Graffenrieda litter only. However, adding of high-quality litter to low-quality litter markedly improved habitat quality, as evaluated by the increase in diversity and density of testate amoebae. The results suggest that local factors, such as litter quality, function as major forces shaping the structure and density of decomposer microfauna that likely feed back to decomposition processes.German Research Foundation (DFG) [FOR 816
Micro- and Macroscale Changes in Density and Diversity of Testate Amoebae of Tropical Montane Rain Forests of Southern Ecuador
No full textWe investigated changes in diversity and density of testate amoebae in epiphytes of trees in tropical montane rain forests of southern Ecuador. Local - microscale [height on tree trunk of 0 (base of tree trunk), 1 and 2 m; TH I, TH II and TH III, respectively] and regional - macroscale (forests at 1000, 2000 and 3000 m) changes were investigated. At the macroscale diversity and density of testate amoebae peaked at 2000 m. At the microscale diversity reached a maximum at TH I, whereas density reached a maximum at TH III. The percentage of empty shells at the macroscale was at a maximum at 2000 m and at the microscale at TH I, whereas the percentage of live cells was at a maximum at 3000 m and at TH III. The diversity of testate amoebae in epiphytes found in the present study was high (113 species). However, only two to nine species were dominant representing 54-85 percent of total living testate amoebae. The results suggest significant variations in density and diversity of testate amoebae at both the micro- and macroscale. However, for testate amoebae density the macroscale appears most important whereas changes in diversity are more pronounced at the microscale.German Research Foundation (DFG) [FOR 402, FOR 816
Micro- and Macroscale Changes in Density and Diversity of Testate Amoebae of Tropical Montane Rain Forests of Southern Ecuador
No full textWe investigated changes in diversity and density of testate amoebae in epiphytes of trees in tropical montane rain forests of southern Ecuador. Local - microscale [height on tree trunk of 0 (base of tree trunk), 1 and 2 m; TH I, TH II and TH III, respectively] and regional - macroscale (forests at 1000, 2000 and 3000 m) changes were investigated. At the macroscale diversity and density of testate amoebae peaked at 2000 m. At the microscale diversity reached a maximum at TH I, whereas density reached a maximum at TH III. The percentage of empty shells at the macroscale was at a maximum at 2000 m and at the microscale at TH I, whereas the percentage of live cells was at a maximum at 3000 m and at TH III. The diversity of testate amoebae in epiphytes found in the present study was high (113 species). However, only two to nine species were dominant representing 54-85 percent of total living testate amoebae. The results suggest significant variations in density and diversity of testate amoebae at both the micro- and macroscale. However, for testate amoebae density the macroscale appears most important whereas changes in diversity are more pronounced at the microscale.German Research Foundation (DFG) [FOR 402, FOR 816
Landscape Assessment (EFForTS - B08) C and N of litter, fine roots and soil 0-10 cm
No full textCarbon and Nitrogen measurments (%) and C-to-N ratio of litter, fine roots and soil 0-10 cm samples
Changes in Nematode Communities and Functional Diversity With the Conversion of Rainforest Into Rubber and Oil Palm Plantations
No full textFocusing on nematodes and their well-developed indices of community, ecosystem structure and function, we investigated the effects of the conversion of rainforest into rubber and oil palm plantations in Sumatra, Indonesia. Land use did not affect the total abundance of litter- and soil-dwelling nematodes, neither in riparian nor in well-drained sites. However, the rainforest nematode community differed from communities in plantations, with differences in litter being more pronounced compared to soil. In litter, fungivores and nematodes with short generation time (c-p2) increased in monoculture plantations, while that of bacterivores, herbivores, and nematodes with longer generation time and higher sensitivity to disturbances (c-p3) decreased. This indicates higher environmental pressure on nematodes in monoculture plantations than in rainforest. In soil of monoculture plantations, bacterivores, and c-p3 nematodes decreased while herbivores increased. This suggests that the damage of plants by nematodes in oil palm plantations exceeds that in rainforest. Overall, nematode functional diversity indices suggest that the stability of the decomposer community is higher in rainforest compared to monoculture plantations. Importantly, functional diversity indices were much more meaningful than nematode abundance. Further, changes with land use manifested more in litter than in soil, reflecting that nematode communities in soil are buffered against changes in land use and associated environmental conditions. Therefore, to fully assess changes in the structure and functioning of decomposer systems with changes in land use, the litter layer, which often receives little attention, requires more careful consideration.Open-Access-Publikationsfonds 201
Impact of tropical lowland rainforest conversion into rubber and oil palm plantations on soil microbial communities
No full textFocusing on Sumatra, a hotspot of tropical lowland rainforest transformation, we investigated effects of the conversion of rainforests into rubber agroforests ("jungle rubber"), intensive rubber, and oil palm plantations on the communities of litter and soil microorganisms and identified factors responsible for these changes. Litter basal respiration, microbial biomass, total bacterial phospholipid fatty acids (PLFAs), and fungal PLFAs did not vary significantly with rainforest conversion. In litter of converted ecosystems, the concentration of certain PLFAs including the Gram-negative bacteria marker PLFA cy17:0 and the Gram-positive bacteria marker PLFA i17:0 was reduced as compared to rainforest, whereas the concentration of the arbuscular mycorrhizal fungi (AMF) marker neutral lipid fatty acid (NLFA) 16:1 omega 5c increased. As indicated by redundancy analysis, litter pH and carbon concentration explained most of the variation in litter microbial community composition. In soil, microbial biomass did not vary significantly with rainforest conversion, whereas basal respiration declined. Total PLFAs and especially that of Gram-negative bacteria decreased, whereas PLFA i17:0 increased with rainforest conversion. The concentration of fungal PLFAs increased with rainforest conversion, whereas NLFA 16:1 omega 5c did not change significantly. Redundancy analysis indicated that soil pH explained most of the variation in soil microbial community composition. Overall, the data suggest that conversion of rainforests into production systems results in more pronounced changes in microbial community composition in soil as compared to litter. In particular, the response of fungi and bacteria was more pronounced in soil, while the response of AMF was more pronounced in litter. Notably, only certain bacterial markers but not those of saprotrophic fungi and AMF were detrimentally affected by rainforest conversion.German Research Foundation (DFG) [CRC990
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