草原露天煤矿区32年土地利用/覆盖及碳储量遥感变化监测

Monitoring Change of Land Use/Cover and Carbon Storage by Remote Sensing in Grassland Open-pit Coal Mine Among 32 Years

草原露天煤矿区资源开采、开垦等人类活动导致土地利用变化及生态系统碳储量不断变化,利用遥感技术可实现准确、快速监测。本文基于1984—2016年共9期的Landsat多时相遥感影像,以内蒙古草原大型露天煤矿区为研究区,利用面向对象决策树方法得到研究区的土地利用信息,进一步利用土地转移矩阵和景观格局指数分析,基于2016年分类结果进行变化监测,高覆盖草地斑块占景观面积比例减少,景观形状指数增加;随着1999年排土场的生态复垦,近年来复垦与采矿区扩增速率基本保持一致;通过年平均温度与降水量建立碳密度估算模型,得到总体固碳-261.07×103t,表现为碳排放。总的来看碳储量出现降低现象,与草地面积转化为农田、采矿区等碳储量较少的土地类型有关,排土场复垦对减缓土地碳储量减少有一定作用。本研究表明:遥感技术可用于受采矿等人类活动影响造成的矿区土地利用/覆盖与碳储量变化特征实时、动态监测与分析,为采取合理的环境保护措施提供了一定的理论依据。

Aiming at the change of land use and the change of ecosystem carbon storage due to human activities such as resource exploitation and reclamation in open pit coal mine areas,remote sensing technology is used to monitoring accurately and quickly.Based on Landsat multi-temporal remote sensing images from 1984 to 2016,using the large opencast coal mine in Inner Mongolia as a study area,the land use information of the study area was obtained using the object-oriented decision tree method.Taking the classification results in 2016 as an example,the change monitoring based on the results of classification results of 2016,the proportion of landscape area in high-coverage grassland decreased and the landscape shape index increased.Based on the land use transfer matrix and landscape pattern index analysis,is increasing.With the reclamation of waste dumps in 1999,the rate of expansion in reclamation and mining areas has basically remained the same in recent years.The carbon density estimation model was established by annual average temperature and precipitation,and the overall carbon fixation is-261.07×10^3t,expressed as carbon emissions.In general,the decrease of carbon storage is related to the conversion of grassland area into farmland and mining area with less carbon storage,and the reclamation of reclaimed land will play a certain role in alleviating the reduction of carbon storage in the land.This study shows that remote sensing technology can be used for real-time and dynamic monitoring and analysis of land use/cover and carbon stock changes caused by human activities such as mining and provide some theoretical basis for reasonable environmental protection measures.