干旱荒漠区植被在交通工程扰动影响下的时空分布特征——以疏勒河流域嘉安高速为例

SPATIO-TEMPORAL DISTRIBUTION CHARACTERISTICS OF VEGETATION UNDER THE INFLUENCE OF TRAFFIC ENGINEERING DISTURBANCE IN ARID DESERT AREA—TAKING JIA'AN EXPRESSWAY IN SHULE RIVER BASIN AS AN EXAMPLE

交通工程建设对干旱荒漠区植被的扰动效应是一个值得重视的科学问题。本文选择位于河西走廊的疏勒河流域作为研究区,以嘉安高速公路沿线的植被为研究对象,采用遥感解译、GIS空间分析等方法,分析了植被覆盖度和地表覆盖的时空分布特征,识别了高速公路建设对植被的扰动效应,定量剖析了高速公路建设对植被的扰动范围,厘清了不同地表覆盖类型对公路建设扰动的响应特征。结果表明:(1)在2000~2019年间,疏勒河流域的荒漠区面积比例在逐年减少,植被覆盖度整体上为改善趋势。(2)研究区内的“耕地”、“草地”、“稀疏植被”、“湿地”和“不透水表面”面积均为增加趋势,而“裸地”的面积占比呈下降趋势,从2000年的83.97%下降2019年的77.55%。(3)高速公路的修建明显改变了沿线的植被景观格局,导致植被覆盖的差异化水平明显提高,植被覆盖度的最大值和最小值之差从公路建设前的0.013增加至0.033。(4)嘉安高速公路修建期间对植被的扰动范围在60 m之内,导致两侧植被呈现“分带”特征,且扰动作用的强度随“距公路距离”增加而减小,符合对数方程的关系。(5)在高速公路建设的扰动下,各地表覆盖类型的植被退化强度有差异,“不透水表面”、“耕地”、“草地”、“湿地”、“稀疏植被”和“裸地”的退化强度逐渐减弱,退化强度指数分别为-0.216、-0.127、-0.112、-0.112、-0.095和-0.007。本文的研究结果有助于更好地理解道路工程对植被的扰动效应,并可以为道路规划和评价相关的模型提供定量参考。

The disturbance effect of traffic engineering construction on vegetation in arid desert areas is a scientific issue worthy of attention.The Shule River Basin,located in the Hexi Corridor,was chosen as the research area,and the vegetation along the Jia'an Expressway was taken as the research object.Remote sensing interpretation,GIS spatial analysis,and other methods were used to analyze the temporal and spatial distribution characteristics of vegetation and land coverage.The disturbance effect of highway construction on vegetation was identified,and the disturbance range of highway construction on vegetation was analyzed quantitatively.Moreover,the response characteristics of different land cover types to road construction disturbances are analyzed.The results show that:(1)From 2000 to 2019,the proportion of desert areas in the Shule River Basin showed a decreasing trend,and vegetation coverage showed an improving trend.(2)The area of"cropland,""grassland,""sparse vegetation,""wetlands,"and"impervious surfaces"in the study area all increased,while the proportion of"bare areas"showed a downward trend,decreasing from 83.97%in 2000 to 77.55%in 2019.(3)The construction of the expressway significantly changed the vegetation landscape pattern along the line,leading to a significant increase in the differentiation level of vegetation coverage.The difference between the maximum and minimum vegetation coverage increased from 0.013(before highway construction)to 0.033.(4)During the construction of the Jia'an Expressway,the disturbance range to the vegetation was within 60 m,causing the vegetation on both sides to show a"zonal"feature,and the intensity of the disturbance decreased with the increase of the"distance from the highway,"which conformed to the relationship of the logarithmic equation.(5)Under the disturbance of expressway construction,the vegetation degradation intensity of different land cover types is different,and the degradation intensity of"impervious surfaces,""cropland,""grassland,""wetland,""sparse vegetation,"and"bare areas"gradually weakened,and the I_road were-0.216,-0.127,-0.112,-0.112,-0.095,and-0.007,respectively.The research results of this paper help to better understand the disturbance effect of road engineering on vegetation and can provide a quantitative reference for models related to road planning and evaluation.