农业机械学报2017，Vol.48Issue(8)：212-218,7.DOI:10.6041/j.issn.1000-1298.2017.08.024
高寒草甸生态系统表层土壤水分时间稳定性研究
Temporal Stability of Surface Soil Moisture in Alpine Meadow Ecosystem on Northern Tibetan Plateau
摘要
Abstract
Surface (0 ～ 7.5 cm) soil water content (SWC) was measured at 82 locations in a typical alpine meadow ecosystem on the northern Tibetan Plateau by using time domain reflectometry for 14 times during the 2015 growing season to evaluate spatial variability and temporal stability of surface SWC.Results showed that the mean SWC of the two transects during the 2015 growing season was 26.0％.SWC had a weak variability in space and a moderate variability in time.The variability of SWC was increased with the increase of SWC.The spatial pattern of SWC at the 82 measuring locations had a weak similarity during July and early August and a strong similarity from middle August to early September.The mean relative difference (MRD) of SWC was from-11.5％ to 8.5％ and the mean standard deviation of relative difference (SDRD) was 8.6％.MRD was correlated with SDRD in a concave curve relationship.Index of temporal stability,mean absolute bias error,root mean square error and minimum-SDRD constant methods could all identify the best representative location and the accuracy of mean SWC estimation of the representative location was high.Comparatively,the minimum-SDRD constant method had a higher accuracy.This study can provide data supplement and method innovation for SWC study in alpine meadow ecosystems.关键词
土壤含水率/时空变异/时间稳定性/代表测点/高寒草甸Key words
soil water content/spatio-temporal variation/temporal stability/representative measurement location/alpine meadow分类
农业科技引用本文复制引用
朱绪超,邵明安,朱军涛,张扬建..高寒草甸生态系统表层土壤水分时间稳定性研究[J].农业机械学报,2017,48(8):212-218,7.基金项目
国家自然科学基金项目(41230746) （41230746）
