Using the InVEST Model to Assess the Impacts of Climate and Land Use Changes on Water Yield in the Upstream Regions of the Shule River Basin

Abstract

Water yield is a key ecosystem function index, directly impacting the sustainable development of the basin economy and ecosystem. Climate and land use/land cover (LULC) changes are the main driving factors affecting water yield. In the context of global climate change, assessing the impacts of climate and LULC changes on water yield in the alpine regions of the Qinghai–Tibet Plateau (QTP) is essential for formulating rational management and development strategies for water resources. On the basis of the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model, we simulated and analyzed the spatiotemporal variations and the impacts of LULC and climate changes on water yield from 2001 to 2019 in the upstream regions of the Shule River Basin (USRB) on the northeastern margin of the QTP. Three scenarios were designed in the InVEST model to clearly analyze the contributions of climate and LULC changes on the variation of water yield. The first scenario integrated climate and LULC change into the model according to the actual conditions. The second scenario was simulation without LULC change, and the third scenario was without climate change. The results showed that (1) the InVEST model had a good performance in estimating water yield (coefficient of determination (R2) = 0.986; root mean square error (RMSE) = 3.012, p < 0.05); (2) the water yield significantly increased in the temporal scale from 2001 to 2019, especially in the high altitude of the marginal regions (accounting for 32.01%), while the northwest regions significantly decreased and accounted for only 8.39% (p < 0.05); (3) the spatial distribution of water yield increased from the middle low-altitude regions to the marginal high-altitude regions; and (4) through the analysis of the three scenarios, the impact of climate change on water yield was 90.56%, while that of LULC change was only 9.44%. This study reveals that climate warming has a positive impact on water yield, which will provide valuable references for the integrated assessment and management of water resources in the Shule River Basin.

Water Yield Modelling, Sensitivity Analysis and Validation: A Study for Portugal

“…PET xj can be calculated by Equation (3) in Figure 2 where K c (l x ) is the vegetation evapotranspiration coefficient associated with the land use type (l x ) in each pixel. In (4) ω( x ) is related to the average annual values of available water capacity (AWC), precipitation, and the Zhang parameter (Z) which is positively correlated with the number of rainfall events (N) per year (Z = 0.2 × N) [4]. AWC(x) is estimated as the product of plant-available water content (PAWC) on pixel x, the minimum of root restricting layer depth and vegetation rooting depth as showing in Equation (5).…”

“…All parameters in the InVEST WYM display some degree of sensitivity [14]. Previous studies (e.g., [4,15]) show that the model can be very sensitive to changes in drivers such as meteorological data and land-use. Extremes variations in those drivers can alter hydrologic cycles, affecting patterns of evapotranspiration, infiltration, and water retention [16].…”

“…Some of those activities result in modifications in the natural landscapes around rivers and wetlands to the point that their biodiversity is put at risk [3]. Water yield is a key ecosystem function index [4], as it is vital to balancing socio-economic development and ecological security [5]. Climate and land use/land cover (LULC) changes are the main driving factors affecting water yield [4].…”

“…Water yield is a key ecosystem function index [4], as it is vital to balancing socio-economic development and ecological security [5]. Climate and land use/land cover (LULC) changes are the main driving factors affecting water yield [4]. For the seventh consecutive year, the Global Risks Report 2018 listed water crises among the top five global risks both in terms of impact and in terms of likelihood [6].…”

Increased Ecosystem Carbon Storage between 2001 and 2019 in the Northeastern Margin of the Qinghai-Tibet Plateau

“…Further, dozens of glaciers lie in this area [37]. The study area has a typical continental climate [38,39], with a low mean annual air temperature, little precipitation, and high actual evaporation [36,37]. The mean annual air temperature and annual precipitation from 1990 to 2019 were −5.24 • C and 201.64 mm, respectively (Figure 2).…”