蔬菜生产水资源消耗特征及节约潜力

Analysis of water resource consumption characteristics and water-saving potential in vegetables production

水资源短缺已经成为农业生产的刚性约束。基于水足迹范式,以代表性露地和设施蔬菜为研究对象,在省际尺度上量化和分析了蔬菜作物生产的耗水强度及产生的水资源压力,运用全局和局部Moran′s I指数探讨了蔬菜耗水强度的空间自相关格局,并在分析蔬菜耗水强度可能影响因素的基础上,通过情景分析揭示了蔬菜生产的节水路径和潜力。结果表明:(1)蔬菜生产耗水强度明显受生产方式和地理位置的影响。露地蔬菜生产的平均耗水强度为72.60 m^(3)/t,是设施蔬菜的2.24倍。此外,设施蔬菜耗水强度存在显著的区域差异,长江中下游和华南地区显著高于东北地区。(2)蔬菜生产水资源压力较大的省份多集中于华北地区,且设施蔬菜耗水强度呈现显著的全局空间聚集。(3)文盲率、灌溉率与露地蔬菜耗水强度呈现显著正相关关系,农业机械总动力与其呈现显著负相关关系;人均蔬菜消费、蔬菜生产者价格指数、农机补贴、产业聚集水平、单产水平及节水灌溉面积均与设施蔬菜耗水强度呈现显著负相关关系。(4)提高灌溉水有效利用系数、改善单产水平、发展设施蔬菜并改善空间上呈现高-高聚集区域的蔬菜耗水强度可减少21.69%的水消耗。研究可为蔬菜生产耗水相关研究提供数据基础,对农业水资源可持续利用与管理具有重要意义。

China′s vegetables output accounted for more than 50%of the world′s total vegetables yields,and the per capita possession of vegetables was 3.4 times the world average.Increasingly intensive vegetables production has occupied an increasing share of regional water resources,and water scarcity has become a rigid constraint on crops production,inevitably limiting the sustainability of vegetable production.Clarifying the water consumption characteristics of current vegetables production in China,and exploring the potential to reduce the water consumption intensity are not only essential components for a comprehensive understanding of water consumption in Chinese agriculture,but also necessary conditions for ensuring food safety.Existing studies on water consumption of vegetables mostly focused on micro experiments,with limitations in objects and scales,which may lead to biases in understanding and managing agricultural water use.Based on the water footprint theory,the water consumption intensity of vegetables,including two different planting patterns(open field vegetables(OPV)and greenhouse vegetables(GHV))and four main vegetable crops(tomato,cucumber,eggplant,sweet peppers),and water scarcity in vegetables production were quantified on the provincial scale.And then the spatial autocorrelation pattern of water consumption intensity of vegetables production was discussed by using global and local Moran′s I index.Lastly,based on the analysis of influencing factors of water consumption intensity by correlation analysis,the water-saving paths and potential of vegetables production were revealed by scenario analysis,which involved improvement of irrigation technology,increase of yield,expansion of GHV and improvement of water consumption intensity.The results showed that:(1)The water consumption intensity of vegetables was obviously influenced by planting patterns and geographical location.The average water consumption intensity of OPV was 72.60 m^(3)/t,which was 2.24 times higher than that of GHV.In addition,there were significant regional differences in the water consumption intensity of GHV,and the middle and lower reaches of the Yangtze River and South China was significantly higher than that in Northeast China.(2)The provinces with higher water resource scarcity in vegetables production were mostly concentrated in North China,and the water consumption intensity of GHV showed a significant global spatial aggregation(Moran′s I=0.3019).From the perspective of local spatial autocorrelation,the water consumption intensity of GHV in Northeast and North China showed significant low-low agglomeration.(3)The illiteracy rate and irrigation rate were significantly positively correlated with the water consumption intensity of OPV;the per capita vegetables consumption,vegetables producer price index,agricultural machinery subsidies,industrial aggregation level,yield level and water-saving irrigation area were significantly negatively correlated with the water consumption intensity of GHV.(4)Improving water utilization efficiency,increasing unit yield of vegetables,developing GHV,and improving water consumption intensity in the high-high agglomeration areas would comprehensively reduce water consumption by 21.69%.This study can provide data basis for the researches on water consumption in vegetables production and has important significance for more comprehensive and sustainable utilization and management of agricultural water resources.