不同放牧制度草地土壤碳氮磷化学计量特征  

Ecological stoichiometric characteristics of soil carbon, nitrogen, and phosphorus under different grazing regimes

作　　者：吴雨晴 田赟[1] 周建琴 张克斌[1] WU Yuqing;TIAN Yun;ZHOU Jianqin;ZHANG Kebin(Key Laboratory of State Forestry Administration on Soil and Water Conservation, Ministry of Education Engineering Research Center of Forestry Ecological Engineering, Beijing Forestry University, Beijing 100083, China)

机构地区：[1]北京林业大学水土保持国家林业局重点实验室林业生态工程教育部工程研究中心

出　　处：《应用与环境生物学报》2019年第4期801-807,共7页Chinese Journal of Applied and Environmental Biology

基　　金：国家重点研发计划项目(2016YFC0500908);中央高校基本科研业务费专项资金(2015ZCQ-SB-03)资助~~

摘　　要：放牧是人类对草地资源管理和利用的主要方式之一,研究不同放牧制度下的草地土壤化学计量特征,可为草地植被的可持续利用和放牧制度的选择提供科学依据.以呼伦贝尔新巴尔虎左旗4种不同放牧制度(禁牧、休牧、划区轮牧和常牧)的草场为研究对象,通过样地调查和土壤碳(C)、氮(N)和磷(P)3种元素含量的测定,分析4种不同放牧制度下土壤化学计量特征及其与植被群落特征和土壤化学性质的相关性.结果显示:禁牧条件下,植被生长状况较好.碳氮磷含量均呈现禁牧>休牧>划区轮牧>常牧的变化趋势;在不同的放牧制度下,土壤碳氮含量集中分布于0-10 cm,且显著高于下层土壤(P < 0.05);4种放牧制度下土壤C/N无明显变化,而常牧区的C/P和N/P均显著低于禁牧区;此外,土壤碳氮磷含量均与pH值呈极显著负相关(P < 0.01),物种丰富度指数和多样性指数均与C/P和N/P呈极显著负相关(P < 0.01).本研究表明磷是该地区主要的限制性养分元素,且磷含量受土壤深度的影响较小;与常牧相比,禁牧、休牧及轮牧均有利于植物生长、土壤理化性质改良以及养分含量积累.Understanding the impact of grazing regimes on ecological stoichiometric characteristics of grassland soil is important for grassland conservation and management. This study aimed to investigate the ecological stoichiometric characteristics of carbon, nitrogen, and phosphorus in the typical temperate grassland of Hulun Buir, Inner Mongolia, China. Plots under different grazing regimes were surveyed, including forbidden grazing, seasonal grazing, rotation grazing, and permanent grazing. We compared four types of grazing regimes by studying vegetation traits, soil properties, and stoichiometric characteristics of soil C, N, and P, and revealed the relationships among them. Under the regime of permanent grazing, vegetation growth was the best. The C, N, and P content was in the following order: forbidden grazing > seasonal grazing > rotation grazing > permanent grazing. Under all four different grazing regimes, the C and N content in the surface soil (0-10 cm) was significantly higher than that in the lower layer (P < 0.05). As for soil stoichiometric ratios, there was no significant change in the C/N among the four different grazing regimes. In contrast, C/P and N/P were the highest in the permanent grazing area and the lowest in permanent grazing area. In addition, the correlation analysis showed that the C, N, and P content was significantly and negatively correlated with pH (P < 0.01), and the species richness index and diversity index were significantly and negatively correlated with C/P and N/P (P < 0.01). P is the main limited nutrient element in the study area, and P content is less affected by soil depth. Compared with permanent grazing, forbidden grazing, seasonal grazing, and rotating grazing are beneficial for plant growth, improvement of edaphic properties, and nutrient accumulation.

关 键 词：放牧制度 化学计量特征 草地土壤 内蒙古 

分 类 号：S812.2[农业科学—草业科学]