The relationships among terrestrial ecosystems, climate change, and human activities are important aspects to consider in the field of global change. Recently, it has become a hot research topic to study the effect of global change and the response of biologically distinct climate regions to the changes on different time and spatial scales. It has become especially important to study, on various spatiotemporal scales, the sensitivity of ecosystems to climate change and anthropogenic pressure in arid areas. However, it is difficult to monitor the temporal change of vegetation on different spatial scales, and as expected, the research achievements on this topic are few. In this study, the mechanisms of ecological effects on climate change and human activities in terrestrial ecosystems were investigated by combining the climate change point detection and trend test methodology; Land use and land cover change (LUCC), and biomass estimation after selecting a typical inland terrestrial ecosystem area:the Yanqi basin in Xinjiang, China. According to the degree of the effect of climate change and human activities, the research area was divided into two parts:a mountain (which was mainly affected by climate change) and plain oasis (which was mainly affected by human activities) at a contour of 1400 m above sea level. In respect to the vegetation, land cover types reflect the change in the ecological environment, and they were divided into the vegetation and non-vegetation cover types. According to type and affect, the land cover was classified as highland vegetation, artificial oasis, natural oasis, bare land, desert, water, glacier, and wetland. The main conclusions drawn from this study encompassed the recent 40 year period between 1973 and 2014 are:(1) distinct change points of precipitation and evaporation in mountain and plain areas of the Yanqi basin were detected by the Mann-Kendall-Sneyers test, the results of the nonparametric Mann-Kendall tests reveal that:the precipitation increased and the evaporation declined in mountain and plain areas in the same fashion; (2) in mountainous areas, the areas considered to be bare land and glacier decreased 5.4% and 3.36%, respectively, whereas the highland vegetation increased by 8.76%. In the plain area, the areas of the natural oasis, artificial oasis and wetland increased 1.96%, 15.41% and 1.27% respectively. The areas of desert and water decreased 1.62% and 1.30%, respectively; (3) biomass in mountain and plain areas distinctly variable, and the main cause attested as coupled effect of climate change and human activities in different scale with different spatiotemporal patterns. Terrestrial ecosystems in mountainous areas are sensitive to climate change, and precipitation is estimated to be the most important factor affecting vegetation growth and distribution; (4) the main reasons for oasis improvement in plain areas include enlarging an artificial oasis by intensified human activities and supporting favorable climate change. Among these reasons, enlargement of agricultural areas to accommodate an increased population and socio-economic development are the driving forces of structural change and the distribution of ecosystems plains. In summary, climate change and human activities are expected to affect terrestrial ecosystems according to different degrees and spatiotemporal patterns in the coming 40 years in Yanqi basin.