广东-广西农业水足迹变化及其驱动力的对比分析

Comparative Analysis of Agricultural Water Footprint Changes in Guangdong and Guangxi and Their Driving Forces

为识别广东与广西农业生产水资源占用及其影响因子,在量化1996—2018年两省(自治区)农业水足迹及其构成的基础上,揭示了农业水足迹强度驱动机制及其区域间差异;广东和广西年均农业水足迹分别为29.88、41.37 Gm^(3),均随时间增长,2018年广西的农业水足迹约为广东省的1.5倍。广东谷物和水果的水足迹合计占比高达80.4%;广西的谷物、水果和糖类的农业水足迹均在12 Gm^(3)左右,三者占比之和达总量89.5%。农业水足迹强度总体上呈现上升—下降—再上升的态势。水足迹组成均表现出蓝水足迹<灰水足迹<绿水足迹的关系,绿水足迹占主导地位。除降水外,经济发展是广东农业水足迹强度的主要驱动要素,而广西的农业生产要素不可忽视。结果可为不同类型农业水足迹调控策略的制定提供参考。

To identify the agricultural water footprints in Guangdong Province and Guangxi Zhuang Autonomous Region and their influencing factors,we quantified the agricultural water footprints in Guangdong and Guangxi over 1996—2018 and their composition and revealed the driving mechanism of agricultural water footprint intensity and its regional differences.The average annual agricultural water footprints in Guangdong and Guangxi were 29.88 Gm^(3) and 41.37 Gm^(3) respectively.Both of them increased with time to the extent that the agricultural water footprint of Guangxi in 2018 was about 1.5 times that of Guangdong.The combined water footprint ratio of cereals and fruits in Guangdong was as high as 80.4%.The agricultural water footprints of cereals,fruits,and sugar in Guangxi were about 12 Gm^(3) each and accounted for 89.5% of the total.On the whole,the agricultural water footprint intensity showed a trend of rising-falling-rising.The composition of the water footprint manifested the relationship of blue water footprint<grey water footprint<green water footprint,and the green water footprint was dominant.In addition to precipitation,economic development is the main driving factor of the agricultural water footprint intensity in Guangdong,while agricultural production factors in Guangxi cannot be ignored.The results can provide a reference for the formulation of regulation strategies for different agricultural water footprints.