不同灌溉量对马铃薯产量和土壤N2O排放的影响

Effects of Different Irrigation levels on Potato Yield and Soil N2O Emission

依托河北省农林科学院旱作农业研究所马铃薯节水试验平台,采用静态暗箱-气相色谱法,研究了在滴灌条件下不同灌溉水平W0(0m^3/ha)、W1(600m^3/ha)、W2(1200m^3/ha)、W3(1800m^3/ha)、W4(2400m^3/ha)对马铃薯产量和土壤N2O排放的影响。结果表明:增加灌溉水量能显著提高马铃薯产量和土壤N2O累积排放量;W4处理获得最大马铃薯产量,约为31765kg/ha,W1、W3处理分别出现N2O累积排放量最小值和最大值;W0对照处理N2O排放通量与土壤湿度呈极显著相关,与土壤温度显著相关;灌溉量为W1时,N2O排放通量与硝态氮含量显著相关,表明低灌溉处理时,土壤湿度、温度和硝态氮含量显著影响土壤N2O排放,而高灌溉处理相关性不显著。综合分析马铃薯产量效益兼顾土壤N2O减排,最优灌溉水平可取2400m^3/ha。

Relying on the potato water-saving test platform of Dry Farming Agriculture Research Institute of Hebei Academy of Agriculture and Forestry Sciences,static chamber-gas chromatography is used to study the effects of W0(0 m^3/ha) W1 (600 m^3/ha) W2 (1200 m^3/ha) W3 (1 800 m^3/ha) W4 (2 400 m^3/ha) on soil N2O emission in potato fields under drip irrigation.The results show that irrigation water addition will significantly increase the potato yield and soil cumulative N2O emission.The potato yield is the largest at irrigation level of W4( 2 400 m^3/ha),which is about 31765 kg/ha.The cumulative N2O emission of W1and W3 treatments are the minimum and maximum respectively.N2O emission flux with W0 treatment is extremely correlated with soil humidity and significantly correlated with soil temperature.In W1 situation,N2O emission flux is significantly correlated with nitrate nitrogen content.That shows at low irrigation levels,the soil humidity,the soil temperature and the nitrate nitrogen content greatly affect the N2O emission,while the high irrigation levels have less correlation.Therefore,the best irrigation level can be 2400 m3/ha,in which the maximum economic benefit can be obtained while the soil N2O emission is lower.