Scenario simulation of water retention services under land use/cover and climate changes: a case study of the Loess Plateau, China

Abstract

Comprehensive assessments of ecosystem services in environments under the influences of human activities and climate change are critical for sustainable regional ecosystem management. Therefore, integrated interdisciplinary modelling has become a major focus of ecosystem service assessment. In this study, we established a model that integrates land use/cover change (LUCC), climate change, and water retention services to evaluate the spatial and temporal variations of water retention services in the Loess Plateau of China in the historical period (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015) and in the future (2020-2050). An improved Markov-Cellular Automata (Markov-CA) model was used to simulate land use/land cover patterns, and ArcGIS 10.2 software was used to simulate and assess water retention services from 2000 to 2050 under six combined scenarios, including three land use/land cover scenarios (historical scenario (HS), ecological protection scenario (EPS), and urban expansion scenario (UES)) and two climate change scenarios (RCP4.5 and RCP8.5, where RCP is the representative concentration pathway). LUCCs in the historical period (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015) and in the future (2020-2050) are dominated by transformations among agricultural land, urban land and grassland. Urban land under UES increased significantly by 0.63×10 3 km 2 /a, which was higher than the increase of urban land under HS and EPS. In the Loess Plateau, water yield decreased by 17.20×10 6 mm and water retention increased by 0.09×10 6 mm in the historical period (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015), especially in the Interior drainage zone and its surrounding areas. In the future (2020-2050), the pixel means of water yield is higher under RCP4.5 scenario (96.63 mm) than under RCP8.5 scenario (95.46 mm), and the pixel means of water retention is higher under RCP4.5 scenario (1.95 mm) than under RCP8.5 scenario (1.38 mm). RCP4.5-EPS shows the highest total water retention capacity on the plateau scale among the six combined scenarios, with the value of 1.27×10 6 mm. Ecological restoration projects in the Loess Plateau have enhanced soil and water retention. However, more attention needs to be paid not only to the simultaneous increase in water retention services and evapotranspiration but also to the type and layout of restored vegetation. Furthermore, urbanization needs to be controlled to prevent uncontrollable LUCCs and climate change. Our findings provide reference data for the regional water and land resources management and the sustainable development of socio-ecological systems in the Loess Plateau under LUCC and climate change scenarios.

Evaluation of the Ecological Effects of Ecological Restoration Programs: A Case Study of the Sloping Land Conversion Program on the Loess Plateau, China

“…For example, Wang et al [28] concluded that the contribution of the SLCP to the increase in vegetation cover in China was about 26.33%, and Zheng et al [29] concluded that the contribution of the SLCP to the increase of vegetation cover on the Loess Plateau was about 42.35%. Third, regarding the impact of the SLCP on ecosystem services, scholars have found that the SLCP has significantly changed the supply of ecosystem services such as water conservation [30][31][32], soil retention [14,23,33,34], carbon storage [35][36][37] and biodiversity [38][39][40] in the study area. Meanwhile, scholars have further investigated the impact of the SLCP on the trade-offs and synergies between different ecosystem services.…”

Analysis of Water Conservation Trends and Drivers in an Alpine Region: A Case Study of the Qilian Mountains

“…Moreover, monthly data were aggregated on an annual basis, preserving the dataset's temporal continuity for the period spanning 2000 to 2020. In previous studies, the meteorological data [36][37][38][39], DEM data [40], and soil data [12,17] used in this study were all verified for accuracy and universality. Table 1 represents further information regarding the data as follows:…”

“…The remaining land cover types are mainly because of fewer crops and shallower root systems, rainfall is easily lost through excessive runoff and infiltration on shallow-rooted soils [76], and surface runoff and evapotranspiration are greater, so the land has a poor water-conserving capacity. From the results of the land transfer matrix, it is evident that ecological protection measures have been insisted on in the study area, such as returning farmland into forests and pasture into grassland for many years, which has greatly improved the situation of serious soil erosion in the Qilian Mountain region [77,78] and greatly increased the area of grassland, which provides a guarantee of the whole ecosystem's water source containment service function [40].…”

Effects of vegetation restoration on local microclimate on the Loess Plateau

“…Since the project was implemented, great achievements have been made. The area of vegetation coverage increased over large areas on the LP, and the increase mainly came from the transfer of cultivated land (Xiu et al, 2019;Sun et al, 2021). For example, a large amount of cultivated land was converted into grassland (2538 km 2 ) and woodland (1491 km 2 ) from 2000 to 2015 (Guo et al, 2019).…”