河北省种植业水污染足迹初报

为进一步评估种植业化肥投入引发水污染对应的环境影响,本文利用水足迹理论结合统计数据,采用Recipe生命周期影响评价法对河北省1995—2014年11个地级市的种植业水污染足迹进行研究。结果表明,2014年河北省农作物单位面积施N量和施P量分别比1995年提高了36.3%、52.5%,1995—2014年间秦皇岛的农作物单位面积年均施N量最高(335.4 kg·hm-2),邯郸的农作物单位面积年均施P量最高(119.1 kg·hm-2);比较1995、2004、2014三年各地市的施肥总量,石家庄农作物N肥施用总量三年均列首位,沧州N肥施用总量增幅最大;邯郸农作物P肥施用总量三年均列首位,承德P肥施用总量增幅最大;近20年石家庄的农作物单位面积水污染足迹(wdf)均值最高(2.350 Ml·H2Oe·hm-2),其次是秦皇岛和邯郸,张家口最低,但秦皇岛的wdf年际增长最显著;比较各地市在1995、2004和2014年种植业区域水污染足迹(WDF),各地市的WDF在三年里均呈增加趋势,其中石家庄的WDF三年均值最高,在1995、2004、2014年均处Ⅰ级区,邯郸的WDF均值位于其次,并在2004、2014年升入Ⅰ级区,且2014年邯郸的WDF超过石家庄居全省首位,秦皇岛的WDF增长比例最大,2014年的WDF比1995年增长了77.4%,而石家庄2014年WDF比1995年增长26.7%,在所有地市中其增长比例最小。本研究为河北省分类指导各地市的农业水资源优化及可持续利用提供依据。

Water degradation footprint of crop production in Hebei Province

To evaluate the environmental impacts of the degradative water caused by fertilizer application in cropping systems, both historical data and the water footprint theory were adopted in the current study. Specifically, the Recipe life cycle assessment method was used to evaluate the water degradation footprint in cropping systems in the 11 cities of Hebei Province from 1995 to 2014. Our results showed that the average application rate of N and P fertilizers in crop production increased by 36.3% and 52.5%, respectively, across Hebei Province from 1995 to 2014. During this period, the annual N application per hectare was highest in Qinhuangdao(335.4 kg·hm^-2), while the annual P application per hectare was highest in Handan(119.1 kg·hm^-2). When focusing on fertilizer application in each city in the years of 1995, 2004, and 2014, N application was found to be greatest in Shijiazhuang and increased at the fastest rate in Cangzhou, while P application was greatest in Handan and increased at the fastest rate in Chengde. In the last 20 years, the annual mean water degradation footprint per unit(wdf) was found to be highest in Shijiazhuang(2.350 Ml·H₂Oe·hm^-2), followed by Qinhuangdao and Handan, and was lowest in Zhangjiakou; the wdf significantly increased in Qinhuangdao. The regional water degradation footprint(WFD) increased for all cities when compared for 1995, 2004, and 2014. The average WDF was highest in Shijiazhuang, which was in the first-level area for all years, followed by Handan, which was in the first-level area in 2004 and 2014; the WDF was highest in Handan in 2014. In addition, the increase ratio of WDF was largest in Qinhuangdao, which increased by 77.4% from 1995 to 2014, whereas the increase was smallest in Shijiazhuang, at only 26.7% from 1995 to 2014. In general, this study can provide some evidence for the optimization and sustainable application of agricultural water resources in each city in Hebei Province.