天山北坡人类活动强度与地表温度的时空关联性

Spatiotemporal correlation between human activity intensity and surface temperature on the north slope of Tianshan Mountains

人类活动强度与地表温度的时空关联研究对于充分认识气候变化的成因和机制、积极适应气候变化、合理开发及保护生态环境等均具有重大意义。本文以地处西北干旱区且对气候变化极为敏感的天山北坡为研究区,基于MODIS数据反演地表温度,以夜间灯光数据、人口分布数据及土地利用数据等共同表征人类活动强度,分析2000—2018年人类活动强度与地表温度的演变特征,并进一步探究二者的时空关联性。研究结果显示:①2000年以来天山北坡平均人类活动强度(0.11)较低,整体呈阶梯式缓慢上升趋势(0.0024 a^(-1)),其中人类活动强度较建设用地和人口规模增加滞后1~2 a。②天山北坡年均地温为7.18℃且呈显著升温态势,变化率(0.02℃·a^(-1))约为全球的2.33倍,春季显著增温(0.068℃·a^(-1))对整体升温的贡献最大;受高程和植被覆盖度等下垫面性状的显著影响,研究区地温空间上呈南低北高特征。③天山北坡人类活动区人类活动强度与地表温度显著正相关,呈东强西弱分布特征,其空间分异与相关性的表达受到人类活动范围、表现形式及土地利用变化等因素的综合影响,农林种植、城市绿化和植树造林等与植被相关的人为干预能够有效减弱人类活动造成的地表增温。本文不仅为人类活动强度的精细刻画提出了新思路,更可为区域人地协调和统筹发展等提供科学参考。

Research on the spatiotemporal correlation between the intensity of human activities and the temperature of earth surfaces is of great significance in many aspects,including fully understanding the causes and mechanisms of climate change,actively adapting to climate change,pursuing rational development,and protecting the ecological environment.The north slope of Tianshan Mountains,located in the arid area of northwestern China,is a typical area that is extremely sensitive to climate change.This paper takes the area as an example to retrieve the surface temperature of the mountain based on MODIS data,characterized by the effect of the intensity of human activities on the night light,population distribution and land use.The evolution characteristics of human activity intensity and surface temperature in the study area from 2000 to 2018 were analyzed,and the spatiotemporal correlation between them was further explored.It is found that:(1)The average human activity intensity(0.11)has kept relatively low since the beginning of the 21st century,and it has been slowly rising in a stepwise manner(0.0024 a^(-1));in addition,the increase in human activity intensity has lagged behind that in construction land and population by 1-2 years.(2)The annual average surface temperature in the area is 7.18℃with an obvious growth.The rate of change(0.02℃·a^(-1))is about 2.33 times that of the world.The striking boost in spring(0.068℃·a^(-1))contributes the most to the overall warming trend.Spatially,the surface temperature is low in the south and high in the north,due to the prominent influence of the underlying surface characteristics,such as elevation and vegetation coverage.(3)The intensity of human activity and the surface temperature are remarkably positively correlated in the areas with intense human activity,showing a strong distribution pattern in the east section and a weak one in the west section.The expression of its spatial differentiation and correlation is comprehensively affected by such factors as scopes of human activities,manifestations,and land-use changes.Vegetation-related human interventions,such as farming and forestry planting,urban greening,and afforestation,can effectively mitigate the surface warming caused by human activities.This study not only puts forward new ideas to finely portray the intensity of human activities,but also offers a scientific reference for regional human-land coordination and overall development.