Integrating Blue and Green Water to Identify Matching Characteristics of Agricultural Water and Land Resources in China

Qingling Geng,Xiaohui He,Hongling Liu,Zhihui Tian

doi:10.3390/w14050685

Abstract

The uneven distribution and spatial mismatch between water and land resources (WLR) limit the utilization efficiency of agricultural water and land resources (AWLR), and then pose a threat to food production. There is a critical need to understand their matching characteristics for strategic resource allocation decisions and management. In this study, a holistic index (RSI) derived from resource equivalency analysis (REA) was developed which contributed to examine the abundance or deficiency of agricultural water and land resources (AWLR) based on the conception of generalized water resources (including blue water and green water). Results indicate that the matching degree of AWLR was the lowest in Northeast China, North China and Gansu in Northwest China, while the highest value was in Xinjiang due to the higher blue water use. In north China, other provinces suffered water scarcity except in Jilin, Liaoning, Henan, while all provinces in south China suffered land scarcity except in Tibet and Jiangsu. Meanwhile, the matching of AWLR was not exactly consistent with the distribution pattern of precipitation. The higher proportion of green water resources was not located in southeast China with rich precipitation; it had to do with water management. Too much or little water resources can result in the increasing of blue water use. The proposed approach can be a powerful instrument to implement public policies and management strategy as an attempt to improve the utilization efficiency and enhance the optimize-allocation of AWLR.

Highlights

Food security is related to the security of a country, and to world peace and social stability
The lower value of the matching degree of AWLR was located in Northeast China, Inner Mongolia, Hebei, Shanxi and Gansu, which is below 500 mm
The combination of the evaluation on the matching and scarcity of AWLR offers a robust methodology for the assessment and identification of resource scarcity

Summary

Introduction

Food security is related to the security of a country, and to world peace and social stability. Countries around the world always put food security on their highpriority political agenda [1]. Water and land resources (WLR) greatly affect national food security. In China, as an agricultural country, agricultural water consumption accounts for more than 60% of total water consumption, of which irrigation water accounts for more than 90% of total agricultural water use, providing food for nearly 20% of the world’s population with only 7% of the world’s cultivated land resources [8]. Addressing the issue of water and land use for agricultural production and ensuring food security is clearly high on China’s political agenda. Better water management is critical to ensuring food security and nutrition, as well as helping to achieve the Sustainable Development Goals (SDGs) [9]

Methods

Results

Discussion

Conclusion