基于MODIS的青海草原产草量及载畜平衡估算  

Estimation of grassland yield and carrying capacity in Qinghai Province based on MODIS data

作　　者：刘建红 黄鑫[2] 何旭洋 申克建 LIU Jianhong;HUANG Xin;HE Xuyang;SHEN Kejian(Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity,Northwest University, Xi’an 710127,Shaanxi,China;College of Urban and Environmental Science,Northwest University, Xi’an 710127,Shaanxi,China;Remote Sensing Center for Agriculture and Animal Husbandry of Qinghai,Xining 810007,Qinghai,China;Chinese Academy of Agricultural Engineering,Beijing 100125,China)

机构地区：[1]西北大学陕西省地表系统与环境承载力重点实验室,陕西西安710127 [2]西北大学城市与环境学院,陕西西安710127 [3]青海省农牧业遥感中心,青海西宁810007 [4]农业部规划设计研究院,北京100125

出　　处：《草业科学》2018年第10期2520-2529,共10页Pratacultural Science

基　　金：国家自然科学基金(41401494);陕西省教育厅基金(14JK1745)

摘　　要：为了科学合理地利用、管理草地,及时准确掌握草原产草量信息和载畜平衡状况,对保障草原的可持续发展具有重要意义。本研究利用2016年5-9月青海的MODIS NDVI、EVI数据和地面调查数据,按草地类型分别建立可食草鲜草产量的估算模型,通过比较基于NDVI和EVI建立的不同产草量估算模型的精度,选出了各类型草地的最优估产模型。在此基础上,计算了不同类型草地的干草产量,并结合畜牧业统计数据估算了青海牧区和半牧区各县(市)的载畜平衡情况。结果表明,1)基于NDVI的可食鲜草产量估算模型精度普遍高于基于EVI的模型,但各类型草地的最优估算模型不同。2)2016年青海省草原干草总产量空间分布差异明显,干草单产在1 200kg·hm-2以上的草地主要分布在东部的禾草草原和高寒草原,干草单产在300kg·hm-2以下的草地主要分布于北部的高寒荒漠以及西部的盐生草甸和高寒草原。对总产草量贡献最大的为高寒草甸,占70.35%。3)2016年青海省29个半牧区和牧区的县(市)中,有21个县(市)为载畜平衡或载畜不足,8个县(市)为超载,并且载畜平衡状况与存栏牲畜密度具有较好的对应关系。Maintaining high grassland production and livestock carrying capacity is important for optimal utilization of grassland and to ensure its sustainable development.In this study,MODIS NDVI,MODIS EVI data,and ground survey data from 2016 were used to establish fresh forage yield estimation models of different grassland types.By comparing the accuracies of different forage yield estimation models based on NDVI and EVI,the optimal estimation model for each grassland type was identified.After this,we calculated hay yield for each grassland type.Finally,based on regional hay yields and local livestock statistics,we evaluated the livestock carrying capacity of each region.The results showed that 1)the accuracies of fresh forage yield-estimating models based on NDVI were generally higher than those of EVI based models;however,the optimal estimation models of different grassland types produced different results;2)significant spatial discrepancies of grassland productivity occurred in Qinghai Province in 2016.Regions with hay yield above 1 200 kg·ha-1 were mainly located in the desert steppe and the grass steppe in the east,and regions with hay yield below 300 kg·ha-1 were mainly located in the north alpine desert,while the salt grass meadows and alpine grassland were located in the west.The highest contribution to total hay yield came from alpine meadows(70.35%).3)Among the 29 counties in the pastoral and farming-pastoral areas,21 counties were well balanced or below-capacity,and the other 8 counties were above-capacity.Moreover,there was a striking relationship between livestock carrying capacity and current livestock density.

关 键 词：青海 MODIS 产草量估算 载畜平衡评价 遥感 时间序列 草地类型 

分 类 号：S812.5[农业科学—草业科学]