Topography-driven differences in soil N transformation constrain N availability in karst ecosystems
文献类型: 外文期刊
作者: Wen, Dongni;Yang, Lin;Ni, Kang;Xu, Xingliang;Yu, Longfei;Elrys, Ahmed S.;Meng, Lei;Zhou, Jinxing;Zhu, Tongbin;Mueller, Christoph
作者机构:
关键词: Karst region;Topographic gradient;Nitrogen availability;Soil microbes;Gross N transformation rates
期刊名称: SCIENCE OF THE TOTAL ENVIRONMENT
ISSN: 0048-9697
年卷期: 2024 年 908 卷
页码:
收录情况: SCIE(2024版) ; ; EI(2024版)
摘要: Fragile karst ecosystems are characterized by complex topographic landscapes associated with high variations in vegetation restoration. Identifying the characteristics and driving factors of nitrogen (N) availability across the topographic gradient is essential to guide vegetation restoration in karst regions. In this study, we collected soil samples and plant leaves along the topographic gradient (ridge, upper slope, middle slope, and foot slope) of convex slopes in the karst fault basin of southwest China, and determined the indicators reflecting soil N availability, N transformation rates, and their controlling factors. Our results showed that foliar N content and 615N value, soil inorganic N content and 615N value, and foliar N:P ratio were substantially lower on the steep hillslopes than on the flat top ridge. Steep slope soils also had a lower enzyme C:N ratio but a higher enzyme N:P ratio than the flat ridge soils. Furthermore, the vector angles calculated by soil extracellular enzyme analysis were below 45o in all studied soils and decreased significantly with increasing slope, indicating that microbial growth was generally limited by N. These results jointly suggest the declines in soil N availability across the topographic gradient, which are further explained by the changes in soil inherent N transformation processes. As the slope became steeper, soil mineralization and autotrophic nitrification (ONH4) rates decreased significantly, while ratio of microbial NH4+ immobilization to ONH4 and NH4+ adsorption rate increased significantly, indicating the decrease in soil inorganic N supply capacity. We further found that deteriorated soil structure, decreased soil organic matter and calcium content, altered microbial abundance, and increased ratios of fungi to bacteria and gram-positive bacteria to gram-negative bacteria were the primary drivers of reduced N transformation rates and N availability across the topographic gradient. Overall, this study highlights the critical role of the topography in controlling soil N availability by regulating N transformation processes in karst regions. The topography should be considered an important factor affecting the functions and services of karst ecosystems.
分类号:
- 相关文献
作者其他论文 更多>>
-
Study on the Nitrogen Response and Low Nitrogen Tolerance Variations in Different Tea Varieties
作者:Zheng, Shenghong;Ni, Kang;Chai, Hongling;Ning, Qiuyan;Cheng, Chen;Kang, Huajing;Liu, Hui;Ruan, Jianyun
关键词:tea plants;nitrogen response;low nitrogen tolerance;ammonia acids;cluster analysis
-
Effect of Fertilization Timing on Nitrogen Uptake in Spring Tea of Different Sprouting Phenological Cultivars: A Field Trial with 15N Tracing
作者:Zhang, Yongli;Ni, Kang;Yang, Xiangde;Long, Lizhi;Ma, Lifeng;Su, Youjian;Ruan, Jianyun
关键词:nitrogen fertilizer;timing effect;N-15 tracing;tea cultivar;nitrogen uptake;thermal condition
-
Large loss of reactive nitrogen and the associated environmental damages from tea production in China
作者:Huang, Xingcheng;Lakshmanan, Prakash;Zhang, Wushuai;Wang, Xiaozhong;Liu, Bin;Ni, Kang;Ruan, Jianyun;Shi, Xiaojun;Chen, Xinping;Zhang, Fusuo
关键词:tea plantation;reactive nitrogen;damage cost;mitigation potential;meta-analysis
-
Transcriptomic and morphologic vascular aberrations underlying FCDIIb etiology
作者:Fang, Chuantao;Zhang, Xiaodan;Yang, Lin;Sun, Licheng;Lu, Yujia;Liu, Yi;Guo, Jingjing;Wang, Min;Tan, Yanfeng;Zhang, Jinsen;Gao, Xin;Zhu, Li;Liu, Guoping;Ren, Maozhi;Xiao, Jianbo;Zhang, Fayong;Ma, Shaojie;Zhao, Rui;Mei, Xinyu;Qi, Dashi
关键词:
-
Hygroscopic stem reshaping promotes long-distance plant dispersal
作者:Luo, Yuhong;Guo, Zhenjie;Chen, Jiquan;Ruan, Wenyuan;Xu, Xingliang;Li, Le;Bao, Yufan;Xu, Nuo;Xin, Xiaoping;Yi, Keke;Eldridge, David J.;Yan, Yuchun
关键词:Cleistogenes squarrosa;hygroscopic reshaping;microfibril arrangement;stem curling;tumble plant
-
Elevated Temperature has a more Stimulating Effect than Elevated Moisture on N Mineralization and Nitrification in a Paddy Soil of Japan
作者:Tang, Shuirong;Bao, Xujiao;Meng, Lei;Xu, Xingkai;Wu, Lei;Tawaraya, Keitaro;Cheng, Weiguo
关键词:N mineralization;Nitrification;Rice paddy;Soil moisture;Temperature sensitivity
-
Global Land Use Change Impacts on Soil Nitrogen Availability and Environmental Losses
作者:Wang, Jing;Uwiragiye, Yves;Cao, Miaomiao;Chen, Meiqi;Fallah, Nyumah;Huang, Yuanyuan .;Huang, Yuanyuan;Cheng, Yi;Cai, Zucong;Xu, Minggang;Chang, Scott X.;Mueller, Christoph
关键词:nitrogen supply;land use change and nitrogen loss