稻草覆盖与化肥减量对山药生长、土壤温度和湿度的影响

Effects of straw mulch and fertilizer reduction on yam growth,soil temperature and humidity

采用雨养山药田间小区试验的方法,研究了稻草覆盖与化肥减量对山药生长、土壤温度和湿度的影响。结果表明,稻草覆盖还田既能明显降低高温时段(14:00)0~5 cm表土层的温度(平均降低1.5~2.4℃),又能明显提高高温干旱期0~5 cm表土层的水分保持能力(平均提高1.2~3.4个百分点),在稻草覆盖还田量相同条件下,化肥减量15%对0~5 cm表土层温度和湿度影响均不明显。由于稻草覆盖的降温保墒效应,山药成熟期产量和生物量均有所提高,分别增产1070~3490 kg/hm2和450~1780 kg/hm2,而在稻草覆盖还田量相同条件下,化肥减量15%则相反,分别减产1420~3615 kg/hm2和550~1368 kg/hm2。就土壤降温保墒和山药增产效应而言,可选择稻草覆盖量为4000~6000 kg/hm2条件下化肥减量15%。

The effects of straw mulch and fertilizer reduction on yam growth,soil temperature and humidity were studied using field trials of rain-fed yam.The results showed that returning straw to the field could not only significantly reduce the temperature of the 0~5 cm topsoil during the high temperature period(14:00)(average decrease of 1.5~2.4℃),but also significantly increase the 0~5 cm top⁃soil during the high temperature and drought periods.The water retention capacity of the layer(an average increase of 1.2~3.4 percent⁃age points),under the same amount of straw cover and return to the field,15%reduction in fertilizer had no significant effect on the temperature and humidity of the 0~5 cm topsoil layer.The yield and biomass of yam during the maturity period were increased due to the cooling and moth-killer effect of straw mulch,increasing yields1070~3490 kg/hm2 and 450~1780 kg/hm2,respectively,while the same amount of straw mulching returned to the fields,the 15%reduction in fertilizers was the opposite,reducing yields1420~3615 kg/hm2 and 550~1368 kg/hm2,respectively.In terms of the effects of soil cooling and soil protection and yam yield increase,when the straw coverage can be selected as 6000~7500 kg/hm2,the fertilizer reduction can be 15%.