摘要
土地覆盖变化是评价生态系统健康的关键,并对可持续发展有重要意义。遥感技术是实现快速动态监测大面积土地覆盖变化的有效方法。结合野外实测土地类型数据和Landsat 8 OLI影像,对欧空局全球土地覆盖产品(CCI-LC)在甘南和川西北地区分类精度评价的基础上,分析了研究区1992-2015年土地覆盖类型的时空动态变化特征,并从自然和人为两方面因素出发,研究了该地区草地面积变化的驱动力。结果表明:1)CCI-LC产品在甘南和川西北地区的总体精度为76.79%,在六大土地覆盖类型中(草地、林地、裸地、水体、永久冰雪和人类占用地),草地的用户精度最高(94.88%)。2)在1992-2015年,草地面积整体上呈减少趋势,且在1994-2001年发生了较大的变化,减少了6760.53 km2,动态度为-0.53%·年-1。3)1992-2000年研究区主要发生草地、林地和人类占用地三者之间的相互转化,其中草地以转出为主;2000-2010年研究区土地覆盖类型的变化多样,草地仍以转出为主,但转出面积较上一时间段大幅度减少;2010-2015年间研究区地物类型的转换关系更加复杂,其中草地以转入为主,转入来源仅为林地和人类占用地。4)农业GDP和牧业GDP是甘南和川西北地区草地面积变化的主要驱动因素,且两者均与草地面积呈负相关关系。提供了一种宏观、快速、低成本分析长时间序列土地覆盖类型动态变化的遥感监测方法。
Land cover change is key information when evaluating ecosystem health and such data is of great significance to planning sustainable development.Remote sensing is an effective way to achieve rapid and dynamic monitoring of land cover changes on a large scale.In this study,field measurement data and Landsat 8 OLI images were used to evaluate the classification accuracy of ESA Global land cover products(CCI-LC)in Gannan Prefecture and Northwest Sichuan,using the CCI-LC data to analyze the spatiotemporal dynamic of land cover types from 1992 to 2015,and the factors driving changes in grassland area changes was studied,considering both natural and artificial factors.The results indicated that:1)The overall accuracy of CCI-LC products in Gannan Prefecture and Northwest Sichuan is 76.79%.Among the six land cover types(grassland,forest,bare land,water,permanent snow and ice,artificial surfaces),the user accuracy of grassland is the highest(94.88%).2)From 1992 to 2015,the grassland area showed a generally decreasing trend,with a marked change during the period 1994-2001,with an overall decrease in area of 6760.53 km2 and a rate of loss of-0.53%·year-1.3)From 1992 to 2000,the main changes in land cover types in the study area involved grassland,forest and artificial surfaces,and grassland area was mainly reduced in this period;from 2000 to 2010,the changes in land cover type in the study area were more diverse.The grassland cover was again reduced in most instances,but at a greatly reduced rate compared to 1992-2000;from 2010 to 2015,the transformation of land types was more complex,but a common pattern was transfer of grassland to forest and artificial surfaces.4)Agricultural GDP and animal husbandry GDP are the main driving factors of grassland area change in Gannan Prefecture and Northwest Sichuan,and both of them are negatively correlated with grassland area.This study provides a macroscopic,rapid and low-cost remote sensing monitoring method to analyze the dynamic changes in land cover types over a long time period.
作者
李元春
葛静
侯蒙京
高宏元
刘洁
包旭莹
殷建鹏
高金龙
冯琦胜
梁天刚
LI Yuan-chun;GE Jing;HOU Meng-jing;GAO Hong-yuan;LIU Jie;BAO Xu-ying;YIN Jian-peng;GAO Jin-long;FENG Qi-sheng;LIANG Tian-gang(State Key Laboratory of Grassland Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China)
出处
《草业学报》
CSCD
北大核心
2020年第3期1-15,共15页
Acta Prataculturae Sinica
基金
国家重点研发计划项目(2017YFC0504801)
国家自然科学基金项目(31672484,31702175,41805086,41801191)
现代农业产业技术体系建设专项资金
中国工程院咨询研究项目(2020-XZ-29,2018-XZ-25)
长江学者和创新团队发展计划(IRT17R50)
中央高校基本科研业务费(lzujbky-2018-it17,lzujbky-2019-kb28)资助。
