基于作物需水量的城市农业水资源评估——以贵州省贵阳市为例

Evaluation of Agricultural Water Resources in Urban Area Based on Crop Water Demand——A Case Study in Guiyang City in Guizhou Proivince

[目的]对贵阳市城市农业绿水和蓝水的水足迹与灌溉效率进行定量研究,为科学定量评估城市农业用水和管理监测提供依据。[方法]利用实地调查数据、贵阳市气象数据与农业统计数据,基于作物需水量、水足迹的方法进行农业水资源评估。[结果]①作物水足迹极值取决于调查样地作物单位面积产量的极值。②贵阳市城市农业不同作物生长的消耗绿水量均高于蓝水量,绿水量和蓝水量的比例范围从最低53.81%(豇豆)到最高63.60%(番茄)。③贵阳市城市农业3种灌溉效率(沟灌、喷灌和滴灌)分别为27.23%,69.45%与80.32%。④2017年贵阳市城市农业蓝色水量灌溉需求量在4.81×10^5 m^3(完全滴灌)与6.93×10^5 m^3(完全沟灌)之间。[结论]2017年贵阳市城市农业总用水需求为1.29×10^6 m^3,其中8.84×10^5 m^3为绿水,4.02×10^5 m^3为蓝水。灌溉方式对贵阳市城市农业用水有较大的提升空间,滴灌方式对贵阳市城市农业水资源管理贡献率达53.09%。

[Objective]This paper conducted a quantitative study on the water footprint and irrigation efficiency of green water and blue water in urban agriculture in guiyang city,so as to provide a basis for scientific quantitative evaluation of urban agricultural water use and management monitoring.[Methods]Using field survey data,meteorological data of Guiyang City and agricultural statistical data,based on crop water demand,water footprint method to evaluate agricultural water resources.[Results]①The extreme value of crop water footprint depends on the extreme value of crop yield per unit area of the sample plot.The green water footprint and blue water footprint were 741.60,153.48,424.44 and 87.84 m^3/t.②The green water consumption of different crops in urban agriculture was higher than the blue water consumption.The proportion of green water and blue water ranged from 53.81%(cowpea)to 63.60%(tomato).③The three irrigation efficiencies of urban agriculture are 27.23%,69.45%and 80.32%,respectively.④In 2017,the urban agricultural blue water irrigation demand is between 4.81×10^5 m^3(complete drip irrigation)and 6.93×10^5 m^3(complete ditch irrigation).[Conclusion]In 2017,the total water demand for urban agriculture in Guiyang City was 1.29×10^6 m^3,of which 8.84×10^5 m^3 was green water and 4.02×10^5 m^3 was blue water.The irrigation method has great room to improve the urban agricultural water use in Guiyang City,and the contribution rate of drip irrigation method to the urban agricultural water resource management in Guiyang City is up to 53.09%.