黄土高原坝控小流域土壤C,N,P计量特征解析

《水土保持研究》[ISSN:1005-3409/CN:61-1272/P] 卷: 25 期数: 2018年03期页码: 17-22,28 栏目: 出版日期: 2018-04-10

Title:: Analysis on Stoichiometry Characteristics of Soil Carbon, Nitrogen and Phosphorus in Small Watershed of the Loss Plateau

作者:: 周玮莹^1,2, 杨明义^1,2; 1. 西北农林科技大学水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室, 陕西杨凌 712100;
2. 中国科学院水利部水土保持研究所, 陕西杨凌 712100

Author(s):: ZHOU Weiying^1,2, YANG Mingyi^1,2; 1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A & F University, Yangling, Shaanxi 712100, China;
2. Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi 712100, China

摘要:: 研究采集了陕西绥德王茂庄流域埝堰沟流域内沟壁裸露地、荒草地及耕地3种利用类型的土壤及坝地沉积泥沙，分析了小流域土壤及沉积泥沙中的碳（C）、氮（N）、磷（P）的化学计量特征，结合泥沙量与降雨侵蚀力的阶段性变化，对流域侵蚀环境进行反演。结果表明：（1）坝控流域内土壤C，N，P含量均值分别为3.36 g/kg，0.35 g/kg，0.68 g/kg，C：N，C：P，N：P均值分别是9.30，5.75，0.60，低于全国平均水平；坝地泥沙的C，N，P含量均值分别为1.76 g/kg，0.20 g/kg，0.55 g/kg，坝地养分未表现出富集效应，研究区土壤的C：N，C：P，N：P比值反映出土壤矿化速度较快但氮素缺乏，限制植物生长；（2） C：P在不同土地利用类型土壤间、土壤与沉积泥沙中均有显著差异，因此可作为泥沙对土地利用类型变化响应的敏感指标；（3）根据泥沙量的累积距平趋势变化曲线可以将流域侵蚀历史划分为4个阶段，结合降雨侵蚀力及C：P值与泥沙量的回归关系，分析了不同阶段降雨和土地利用变化对侵蚀泥沙的贡献。

Abstract:: The check dam sediment and soils in three types of land-use of Wangmaogou Watershed in Suide County of Shaanxi Province were collected. To reproduce the change of erosion environment in small watershed, based on periodic change of sediment yield and rainfall erosivity, carbon(C), nitrogen(N) and phosphorus(P) stoichiometry of soil in small watershed and check dam sediment were analyzed. The results indicated that:(1) the mean contents of soil carbon, nitrogen and phosphorus were 3.36 g/kg, 0.35 g/kg, 0.68 g/kg, the mean values of C:N, C:P, N:P were 9.30, 5.75, 0.60, lower than average of those of China soils; The mean contents of sediment carbon, nitrogen and phosphorus were 1.76 g/kg, 0.20 g/kg, 0.55 g/kg; soil C:N, C:P, N:P of the study area reflected the fast soil mineralization but lack of nitrogen, which limited the growth of plants; (2) C:P ratios among different land-used types, soil and sediment presented significant differences, which means of C:P can be used as the sensitive index indicating the response of sediment to land use types; (3) according to sediment yield, rainfall erosivity and C:P value accumulation curve, erosion can be divided into four phases, and on the basis of the relationship between rainfall erosivity and sediment yield, the contributions of the different stages of rainfall and land use change to erosion and sediment can be determined.

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更新日期/Last Update: 1900-01-01