Ecological stoichiometry of Cinnamomum migao leaf litter and soil nutrients under nitrogen deposition in a karst region

Ecosphere

Jia Li¹  Jiming Liu¹  Qiuxiao Yan¹  Xuefeng Xiao¹  Deng Wang¹  Jingzhong Chen¹  Xiaofeng Liao² 

[1] Forestry College Research Center of Forest Ecology Guizhou University Guiyang 550025 China;Institute of Mountain Resources Guizhou Academy of Science Guiyang 550001 China;

关键词: Cinnamomum migao;    ecological stoichiometry;    karst region;    litter decomposition;    nitrogen deposition;    soil nutrient;   

DOI  :  10.1002/ecs2.3738

来源: DOAJ

【 摘 要 】

Abstract Nitrogen (N) deposition, a major phenomenon of climate change, is increasing with industrialization and more human activity and can affect litter decomposition. Yet it remains unclear whether N deposition will accelerate or inhibit the decomposition of litter in karst regions, which are characterized by P‐limitation or N and P co‐limited stress conditions in soil. Here, to document the influence of simulated N deposition on litter decomposition in karst, the leaf litter of Cinnamomum migao was studied, this being a dominant perennial woody plant endemic to karst landforms. We conducted a 300‐d field decomposition experiment with four treatments: control (CK); addition of (+) N at 50 kg⋅ha−1⋅a−1 (N1); +N at 150 kg⋅ha−1⋅a−1 (N2), and +N at 300 kg⋅ha−1⋅a−1 (N3), in southwest Guizhou, the largest karst region in China (n = 4 treatments). From each treatment, the litter samples’ remaining mass were measured during the decomposition period, in addition to their nitrogen (N), phosphorus (P), carbon (C), and potassium (K) concentrations, as well as that of soils; the soil’s pH was also measured. The results showed that litter remaining mass increased significantly under nitrogen deposition, which, as expected, acidified the soil. Meanwhile, litter N, P, and K contents responded to nitrogen deposition, whereas C did not. Otherwise, no direct effects of nitrogen deposition upon soil nutrients were detected. The soil nutrient contents were related to the release of the elements in litter. In conclusion, nitrogen deposition suppressed the decomposition of C. migao litter in karst, but the nutrients of karst soil are mainly replenished by litter inputs.

【 授权许可】

Unknown