Abstract：
The swift proliferation of forests converted into monoculture plantations has profound impacts on soil nutrients, microbial communities, and many ecological processes and functions. Nematodes are soil microfauna that play a pivotal role in biogeochemical cycling and in soil food web, whereas the response of soil nematode communities and energy flows to forest conversion remains unknown. Here, we assessed the community composition and the energy flows of the nematode food webs as a function of soil chemistry after conversion from natural forests (Forest) to four plantations (8-year-old): Amygdalus persica (Peach), Myrica rubra (Berry), Camellia oleifera (Oil), and Cunninghamia lanceolata (Fir). After forest conversion, soil organic carbon (SOC) and total nitrogen (TN) contents decreased by 65 % and 55 %, respectively. Forest conversion strongly reduced the abundance (particularly large-bodied omnivorous-predatory nematodes), diversity, maturity, and stability of the soil nematode community. The shifts in composition and structure of nematode communities after forest conversion are reflected in changes in the abundance of predominant genera and trophic taxa, especially bacterivorous, fungivorous, and omnivorous-predatory nematodes. Acrobeloides notably increased, whereas Plectus, Prismatolaimus, Tylencholaimus, and Tripyla decreased. Accordingly, the abundances of r-strategy nematodes (cp value = 1-2) increased, but that of the K-strategists (cp value = 3-5) declined. Additionally, the energy flow across the soil nematode food web was reduced by 36 % and flow uniformity declined by 24 % after forest conversion. These changes in nematode diversity and abundance were triggered by diminishing soil C and N contents, thereby affecting the energy flows via the nematode food webs. Thus, forest conversion affects soil biotas and multi-functions from the perspective of nematode food web structure and energy flows, and underlines the interconnections between ecosystem and energy dynamics across multi-trophic levels, which is crucial for sustainable forest management.
摘要：
转变为单一种植园的森林的迅速增殖对土壤养分产生了深远的影响，微生物群落,以及许多生态过程和功能。线虫是土壤微动物，在生物地球化学循环和土壤食物网中发挥着关键作用，而土壤线虫群落和能量流对森林转化的反应仍然未知。这里,我们评估了从天然林（森林）转化为四个种植园（8岁）后，线虫食物网的群落组成和能量流作为土壤化学的函数：桃子（桃子），杨梅（浆果），油茶(油),和杉木（杉木）。森林转换后，土壤有机碳(SOC)和全氮(TN)含量分别下降65%和55%,分别。森林转化显着降低了丰度（特别是大型杂食性掠夺性线虫），多样性,成熟，和土壤线虫群落的稳定性。森林转换后线虫群落组成和结构的变化反映在主要属和营养类群的丰度变化中，尤其是细菌，真菌,和杂食性食肉线虫。Acrobeloides显著增加，而Plectus，Prismatolaimus,Tylencholaimus,和Tripyla减少。因此，r策略线虫的丰度(cp值=1-2)增加，但K策略师的数据(cp值=3-5)下降了。此外,森林转换后，穿过土壤线虫食物网的能量流减少了36％，流量均匀性下降了24％。土壤C和N含量的减少引发了线虫多样性和丰度的变化，从而影响通过线虫食物网的能量流。因此，森林转化从线虫食物网结构和能量流动的角度影响土壤生物和多功能，并强调了生态系统和能量动态之间的相互联系，这对可持续森林管理至关重要。
