甘肃岷县漳县MS6.6地震前后岷县植被覆盖度动态变化  

Vegetation Cover Dynamic Changes of Minxian Before and After Minxian-Zhangxian MS6.6 Earthquake in Gansu Province

作　　者：孙艳萍 周中红 卢嘉 SUN Yanping;ZHOU Zhonghong;LU Jia(Gansu Earthquake Agency,Lanzhou 730000,China;College of Forestry,Gansu Agriculture University,Lanzhou 730070,China)

机构地区：[1]甘肃省地震局,兰州730000 [2]甘肃农业大学林学院,兰州730070

出　　处：《华北地震科学》2020年第1期72-76,共5页North China Earthquake Sciences

基　　金：“十三五”国家重点研发计划项目(2017YFC1500905)。

摘　　要：利用Landsat8遥感影像数据,应用像元二分模型估算了岷县植被覆盖度,分析了岷县漳县地震前后岷县植被覆盖度动态变化,并结合高程和坡度数据,研究了地形因素对植被受损和恢复的影响,结果表明:3个时段岷县植被覆盖度以中高和高植被覆盖度为主,反映出研究区植被覆盖状况良好。①空间分布上来看,中高和高植被覆盖度主要分布在岷县西南和东南部的高海拔地区,低植被覆盖区由岷县县城所在地向西北方向两侧沿居民地延展;②2013-2014年平均植被覆盖度下降了0.09,受损面积达到96.53%,主要为高植被覆盖度植被受损,植被受损在高程上主要分布在2 344~3 283 m,坡度5°~35°范围是植被受损的主要区域;③2014-2017年平均植被覆盖度回升至0.43,恢复面积达2 901.93 km^2,以高植被覆盖度植被恢复为主,其次为低植被覆盖度;植被恢复在高程2 031~2 970 m,呈增长趋势,随后开始下降,在坡度0°~25°范围内植被恢复面积呈增加趋势,随后降低。Using the Landsat8 remote sensing image data, the imidiate pixel model was used to estimate the vegetation coverage of Minxian county before and after the Minxian-Zhangxian MS6.6 earthquake, and combined with elevation and slope data, the effects of topographic factors on vegetation damage and restoration were studied. The results showed that: The vegetation coverage of Minxian County in the three periods was mainly medium and high vegetation coverage, reflecting the good vegetation coverage in the study area. ① In terms of spatial distribution, the mediumhigh and high-vegetation coverage is mainly distributed in the high-altitude areas in the southwest and southeast of Jixian County, and the low-vegetation coverage area is extended along the residential areas from the location of the Jixian County to the northwest. ② From 2013 to 2014, the average vegetation coverage decreased by 0.09, and the damaged area reached 96.53%, mainly due to the damage of vegetation with high vegetation coverage. Vegetation damage is mainly distributed in the elevation of 2 344~3 283 m, and the slope of 5°~35° is the main area of vegetation damage. ③From 2014 to 2017, the average vegetation coverage rose to 0.43, and the restored area reached 2 901.93 km2. Vegetation restoration was dominated by vegetation restoration with high vegetation coverage, followed by low vegetation coverage. The vegetation restoration showed an increasing trend at an elevation of 2 031~2 970 m, and then began to decline. The vegetation restoration area showed an increasing trend at a slope of 0°~25°, and then decreased.

关 键 词：植被覆盖度 像元二分模型 岷县漳县地震 动态变化 

分 类 号：P315.728[天文地球—地震学]