放牧生态系统枯落物及其作用  

Litter and its functions in grazing ecosystems

作　　者：马周文 王迎新[1] 王宏 阿不满 张贞明 侯扶江[1] 

机构地区：[1]草地农业生态系统国家重点实验室,兰州大学草地农业科技学院,甘肃兰州730020 [2]玛曲县阿孜畜牧科技示范园区,甘肃玛曲747300 [3]甘肃省草原技术推广总站,甘肃兰州730000

出　　处：《草业学报》2017年第7期201-212,共12页Acta Prataculturae Sinica

基　　金：国家自然科学基金(31672472);甘肃省退牧还草科技支撑(2015620111000485);国家科技支撑计划(2012BAD13B05)资助

摘　　要：草地枯落物是连接放牧生态系统中"土—草"界面的主要媒介,是调控地上-地下生态过程的关键因子,对草地物种多样性、生产力、退化草地恢复等具有重要意义。一方面,家畜的采食、践踏、排泄物等减少枯落物积累和加速其分解,且与放牧强度、制度、季节、家畜种类联合响应;另一方面,枯落物影响家畜的选择性采食、蹄压等行为,为微生物和小草食动物生命活动提供有利场所及能量,进而影响草地生态系统结构及功能。枯落物也能够改变土壤理化性质和物质循环,产生化感物质,影响种子发芽、幼苗生长,导致草地群落构建和演替。本研究综述了国内外相关文献,探讨放牧生态系统中的枯落物及其作用,旨在明确草地生态系统中"放牧-枯落物-土壤-绿色植物"之间的相互作用机制,为后续草地可持续性管理研究提供理论依据。Plant litter is the main medium at the soil-grass interface in grassland ecosystems,and is one of the key factors regulating above-ground ecological processes.Plant litter dynamics are important for grassland species diversity and productivity,as well as for the restoration of degraded grasslands.Livestock affect litter dynamics through feeding,trampling,and their excretions,which can reduce litter accumulation and accelerate its decomposition.These activities vary depending on the stocking rate,grazing season,grazing system,and animal species.Litter affects the selective feeding and hoof pressure of livestock.Plant litter can provide favorable sites for microorganisms and small herbivores,thus affecting the structure and function of the grassland ecosystem.Litter dynamics can also change the physical and chemical properties of soil and affect nutrient cycling.Soil nutrient status and allelochemicals in plant litter can affect seed germination and seedling growth,which contribute to grassland community structure and succession.In this paper,we review the literature related to litter and its role in grazed-grassland ecosystems to understand the interactions among grazing animals,litter,soil,and plants in these environments.Our long-term aim is to provide a theoretical basis for the sustainable management of grassland ecosystems.

关 键 词：放牧 生态系统 草地枯落物 功能 群落演替 

分 类 号：S812[农业科学—草业科学]