摘要
湿地是地球上最具生态功能的生态系统之一,在保持水土、调节气候、保护物种多样性方面发挥着重要作用。笔者以若尔盖湿地为研究对象,1991-2020年Landsat影像为研究数据,基于最大似然法提取湿地信息,后利用计算得到的景观格局指数以及景观组分面积转移矩阵对若尔盖湿地的景观格局进行演变分析。研究表明:①受研究区特殊的地势条件影响,研究区的湿地分布存在明显的空间差异。大面积的泥炭沼泽湿地分布在地势低洼的若尔盖县、玛曲县的东部以及红原县的北部区域。研究区东部的湿地呈上升的趋势,而西部即靠近玛曲县东部的区域湿地面积明显下降。②1991—2020年研究区的湿地面积变化呈先减小后增大再缓慢下降的趋势,湿地总体面积下降20855.69 hm^(2)。1991-2020年研究区湿地景观破碎度呈先减小后增大的趋势,但总体景观破碎度呈上升。总体来看湿地景观破碎度变化较小,若尔盖湿地总体景观格局未发生太大变化。③研究区核心景观基质为草甸,景观组分的变化趋势是其他组分先一定面积转化为草甸后又小幅度恢复,在草本沼泽的面积变化上表现较为突出。④气温升高降水量下降以及人类活动的干扰加速了若尔盖湿地由河流→湖泊→泥炭沼泽→草本沼泽→草甸→裸地发展方向演变。若尔盖湿地的退化并不是一个简单的自然过程,而是在自然因素与人为因素共同作用下反馈的结果。
A wetland is one of the most ecologically functional ecosystems on the earth and plays an important role in water and soil conservation,climate regulation,and species diversity protection.This paper takes Zoige wetland as the research object,Landsat images from 1991 to 2020 as the research data,extracts wetland information based on the maximum likelihood method and then uses the calculated landscape pattern index and landscape component area transfer matrix to analyze the landscape pattern evolution of Zoige wetland.The research shows that:(1)Due to the particular terrain conditions in the study area,there are significant spatial differences in the distribution of wetlands in the study area.Large peat swamp wetlands are distributed in the low-lying areas of Zoige County,the east of Maqu County,and the north of Hongyuan County.The wetland area in the east of the study area shows an upward trend,while the wetland area in the west,which is close to the east of Maqu County,is significantly lower.(2)From 1991 to 2020,the wetland area change in the study area showed a trend of first decreasing,then increasing,then slowly decreasing,and the total wetland area decreased by 20855.69 hectares.From 1991 to 2020,the fragmentation degree of the wetland landscape in the study area decreased and then increased,but the overall fragmentation degree of the landscape increased.In general,the change in wetland landscape fragmentation is small,and the overall landscape pattern of Zoige wetland has not changed much.(3)The core landscape matrix in the study area is meadow,and the change trend of landscape components is that other components first convert into meadow in a specific area and then recover slightly,which is more prominent in the area change of herbaceous marsh.(4)The increase in temperature and the decrease in precipitation,as well as the interference of human activities,accelerated the development of Zoige wetland from river→lake→peat swamp→herbaceous swamp→meadow→bare land.The degradation of Zoige wetland is not
作者
孙玉
陈建华
刘帅
王炳乾
唐翼鹏
陈炯玲
潘芸
SUN Yu;CHEN Jianhua;LIU Shuai;WANG Bingqian;TANG Yipeng;CHEN Jiongling;PAN Yun(College of Geophysics,Chengdu University of Technology,Chengdu 610059,China;College of Geosciences,Chengdu University of Technology,Chengdu 610059,China)
出处
《物探化探计算技术》
CAS
2024年第3期366-376,共11页
Computing Techniques For Geophysical and Geochemical Exploration
基金
四川省阿坝州科技计划项目(R21YYJSYJ0011)。
