College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China.
Department of Civil and Environmental Engineering, Penn State University, University Park, PA 16801, USA.
Int J Environ Res Public Health. 2019 Jul 25;16(15):2669. doi: 10.3390/ijerph16152669.
Alternative irrigation between saline water and groundwater can alleviate shortages of available agricultural water while effectively slowing the adverse effects of saline water on the soil-crop system when compared with continuous irrigation with saline water and blending irrigation between saline water and groundwater. In 2018, we tested the effect on soil CO and NO emissions by two types of irrigation regimes (alternating groundwater and saline water (GW-SW), and alternating groundwater, followed by two cycles of saline water (GW-SW-SW)) between groundwater and three levels of salinity of irrigation water (mineralization of 2 g/L, 3.5 g/L, and 5 g/L), analyzed the correlation between gas emissions and soil properties, calculated comprehensive global warming potential (GWP), and investigated the maize yield. The results show that, with the same alternate irrigation regime, cumulative CO emissions decreased with increasing irrigation water salinity, and cumulative NO emissions increased. Cumulative CO emissions were higher in the GW-SW regime for the same irrigation water salinity, and cumulative NO emissions were higher in the GW-SW-SW regime. The GW-SW-SW regime had less comprehensive GWP and maize yield as compared to the GW-SW regime. The 2 g/L salinity in both regimes showed larger comprehensive GWP and maize yield. The 3.5 g/L salinity under the GW-SW regime will be the best choice while considering that the smaller comprehensive GWP and the larger maize yield are appropriate for agricultural implication. Fertilizer type and irrigation amount can be taken into consideration in future research direction.
交替利用地下水和咸水灌溉可以缓解农业用水短缺的问题，与连续利用咸水灌溉和咸水与地下水混合灌溉相比，这种方法可以有效减缓咸水对土壤-作物系统的不利影响。2018 年，我们测试了两种灌溉制度（地下水和咸水交替灌溉（GW-SW），以及地下水交替，然后进行两次咸水灌溉循环（GW-SW-SW））对土壤 CO 和 NO 排放的影响，分析了气体排放与土壤性质之间的相关性，计算了综合全球变暖潜势（GWP），并调查了玉米产量。结果表明，在相同的交替灌溉制度下，随着灌溉水盐度的增加，累积 CO 排放减少，累积 NO 排放增加。对于相同的灌溉水盐度，GW-SW 制度下的累积 CO 排放更高，GW-SW-SW 制度下的累积 NO 排放更高。与 GW-SW 制度相比，GW-SW-SW 制度的综合 GWP 和玉米产量更低。在这两种制度下，2 g/L 的盐度显示出更大的综合 GWP 和玉米产量。考虑到较小的综合 GWP 和更大的玉米产量更适合农业应用，GW-SW 制度下 3.5 g/L 的盐度将是最佳选择。在未来的研究方向中，可以考虑肥料类型和灌溉量。
