西藏草地净初级生产力的时空格局演变及其驱动机制分析  

Analysis of the Spatial-Temporal Evolution Patterns of Grassland Net Primary Productivity and Its Driving Mechanisms in the Tibet

作　　者：巴桑参木决 温仲明[1] 刘洋洋[1] 周荣磊 任涵玉 林子琦 张志新[1] 王亦波 张格语 BASANG Can-mujue;WEN Zhong-ming;LIU Yang-yang;ZHOU Rong-lei;REN Han-yu;LIN Zi-qi;ZHANG Zhi-xin;WANG Yi-bo;ZHANG Ge-yu(College of Grassland Agriculture, Northwest Agriculture and Forestry University, Yangling, Shaanxi Province 712100, China;Agriculture and Animal Husbandry Service Center of Ningzhong Township Damxung County, Lasa, Tibet 851500, China)

机构地区：[1]西北农林科技大学草业与草原学院,陕西杨凌712100 [2]西藏拉萨市当雄县宁中乡农牧综合服务中心,西藏拉萨851500

出　　处：《草地学报》2022年第4期778-789,共12页Acta Agrestia Sinica

基　　金：国家自然科学基金(42107512);西北农林科技大学—西藏农牧学院联合基金项(2452020044);西北农林科技大学博士科研启动金(2452020186);陕西省林业科学院科技创新计划专项(SXLK2020-0204);中国博士后科学基金(2020M683594);国家科技基础条件平台建设项目(2005DKA32300)资助。

摘　　要：本研究基于遥感和气象数据,采用净初级生产力(Net primary productivity,NPP)作为草地指标,辅以模型模拟和野外观测等方法探究西藏草地NPP的格局演化特征,并探究其潜在驱动因素。结果表明:研究期内西藏草地NPP年均值为136.46 gC·m^(-2)·a^(-1),并以1.57 gC·m^(-2)·a^(-1)的变化率显著增加;草地NPP呈现由东南到西北方向递减的变化趋势。林芝、那曲等地的草地NPP未来将呈持续增加或减少趋势,而日喀则、阿里和那曲交界处的草地NPP未来将出现反持续变化趋势。不同类型草地NPP也存在较大差异,其中高山亚高山草甸最高,平原草地最低;草地NPP与气温呈正相关关系,与降水量相关性不显著,说明气温是该区域草地NPP的限制性气候因子;人类活动如划区轮牧及围栏封育等政策的实施对于近年来西藏草地NPP的增加具有重要促进作用。In this study,based on remote sensing and meteorological data,the evolution pattern and its potential driving factors of Tibetan grassland NPP(Spatiotemporal dynamics,Stability and continuity)were analyzed by using the Net primary productivity(NPP)combined with model simulation and field observations in this study.The results showed that the annual mean NPP of grassland in Tibet was 136.46 gC·m^(-2)·a^(-1),and it showed a significant increasing trend with the change rate of 1.57 gC·m^(-2)·a^(-1) during the study period.Grassland NPP showed a decreasing trend from southeast to northwest.In terms of future changes,the grassland NPP in Nyingchi,Nagqu and other places will consistently increase or decrease,while the junction of Xigaze,Ali,and Nagqu show an inconsistent tendency.The NPP distribution of different grassland types was also quite different,the alpine and subalpine meadows have the highest NPP value,while plain grasslands were the lowest.Grassland NPP was positively correlated with temperature,but not significantly correlated with precipitation,indicating that temperature was the limiting climate factor for grassland NPP in the region.The implementation of policies for human activities,such as rotation grazing in areas,fences,and enclosures has played an important role in promoting the increase of grassland NPP in Tibet.

关 键 词：西藏 净初级生产力 草地动态 气候变化 人类活动 

分 类 号：Q145[生物学—生态学]