Water Conservation Estimation Based on Time Series NDVI in the Yellow River Basin

Abstract

Accurate estimation of the water conservation is of great significance for ecological red line planning. The water conservation of the Yellow River Basin has a vital influence on the development of the environment and the supply of ecological services in China. However, the existing methods used to estimate water conservation have many disadvantages, such as requiring numerous parameters, a complex calculation model, and using data that is often difficult acquire. It is often hard to provide sufficiently precise parameters and data, resulting in a large amount of calculation time and the difficulties in the study of large scale and long time series. In this study, a time series of the Normalized Difference Vegetation Index (NDVI) was applied to estimate water conservation in two aspects using the idea of wholeness and stratification, respectively. The overall fitting results can explain nearly 30% of the water conservation by partial least squares regression and nearly 50% of it by a support vector machine. However, the results of a stratified simulation showed that water conservation and the NDVI have a certain stratified heterogeneity among different ecosystem types. The optimal fitting result was achieved in a water/wetland ecosystem with the highest coefficient of determination (R2P) of 0.768 by the stratified support vector machine (SVM) model, followed by the forest and grassland ecosystem (both R2P of 0.698). The spatial mapping results showed that this method was most suitable for grassland ecosystem, followed by forest ecosystem. According to the results generated using the NDVI time series data, it is feasible to complete a spatial simulation of water conservation. This research can provide a reference for calculating regional or large-scale water conservation and in ecological red line planning.

Spatiotemporal Evolution Characteristics and Driving Factors of Water Conservation Service in Jiangxi Province from 2001 to 2020

“…Natural and human activity factors jointly influenced the spatiotemporal evolutionary characteristics of water conservation services in Jiangxi Province. Researchers have reached similar conclusions in the Yellow River Basin [63], Danjiang River Basin [49], Tumen River Basin [10], and Taohe River Basin [64]. However, previous studies have used correlation analysis or principal component analysis to explore the relationship between factors and water conservation and thus were not able to elucidate the interaction between factors or reflect regional differences in the influence of driving factors.…”

Researching how to match supply and demand for ecosystem services based on multi-source data: A Case Study in the Hexi Region, China

“…This is due to the e cient use of cultivated land resources and improved agricultural and animal husbandry practices [12]. At the same time, with the implementation of a series of national ecological policies, such as the "Turn marginal farmland into forest or grassland" project and the "The Three-North Shelter Forest" project, forest and grass cover has increased signi cantly [47], which has a promoting effect on the increase of carbon sequestration supply. After 2010, the "Turn marginal farmland into forest or grassland" project entered the consolidation period, with the area of forest and grassland reduced and the water yield decreased relatively.…”

Spatiotemporal evolution characteristics and driving forces of vegetation cover variations in the Chengdu-Chongqing region of China under the background of rapid urbanization

“…In China, relevant research mainly concentrated on the Qinghai-Tibet Plateau (Liu et al 2017), the middle and upper reaches of the Yangtze River (Qu et al 2018), and the Yellow River basin (Zhang et al 2021). Alterations in terrestrial ecosystems are primarily influenced by two key factors: shifts in climatic patterns and human interventions (He et al 2015;Liu et al 2019).…”