不同材料覆盖的土壤水温效应及对玉米生长的影响

Effects of Different Mulching Materials on Soil Water,Temperature,and Corn Growth

在渭北旱塬区采用随机区组试验,对比研究了生物降解膜(S)、塑料地膜(D)、秸秆(J)、液态膜(Y)覆盖和裸地平作种植玉米的土壤水温效应及玉米生长状况。结果表明,玉米进入抽雄期和灌浆期后,不同覆盖材料间土壤水分出现较大差异,40～160cmJ覆盖土壤平均含水量显著(P<0.05)高于对照和其他覆盖;S和D覆盖对较深土层(60～120cm)的水分利用加强。J覆盖保墒效果好于其他处理,玉米生长前期主要提高0～100cm土壤含水量,后期提高100～200cm土壤含水量;S和D覆盖的保墒效果主要表现在玉米营养生长阶段的浅层土壤。玉米营养生长阶段5～25cm平均地温,S和D覆盖分别提高1.4℃和2.6℃,J和Y覆盖分别降低3.0℃和0.8℃。S和D覆盖水温协同,延长了玉米营养生长时间,使玉米全生育期提前11d,J覆盖由于降低地温使全生育期延长3d,液态膜不影响生育进程。S和D覆盖显著(P<0.05)提高了玉米穗长、穗粗和行粒数及地上部干重,Y覆盖显著(P<0.05)增加玉米的百粒重,J覆盖显著(P<0.05)降低了玉米穗长、行粒数和百粒重。4种覆盖均不同程度降低了玉米的经济系数,S、D和Y覆盖玉米分别增产26.9%(P<0.05)、34.7%(P<0.05)和2.4%,J覆盖造成玉米减产10.5%。

The study,with randomized block design,measured the effects of different mulching materials which included biodegradable film（S）,plastic film（D）,corn straw（J）,liquid film（Y） and bare land on soil water,temperature and corn growth in Weibei rainfed tableland,which would be as the basis of mulching cultivation in this area.The results showed that soil moisture in different mulchings showed different characteristics after heading and filling stage of corn,soil average moisture（40-60 cm） of J mulching was evidently（P〈0.05） higher than that of control treatment and other mulchings;water deprivation of S and D mulchings were improved in the deeper soil layers（60-120 cm）.Soil water retention of J mulching was better than that of other treatments,J mulching mainly improved the soil moisture in 0-100 cm layer before heading stage,and in 100-200 cm layer after heading stage;S and D mulchings mainly improved the soil moisture in shallower layer before heading stage.The average soil temperature in 5-25 cm soil layer before heading stage increased 1.4℃,2.6℃ in S and D treatments and brought down 3.0℃,0.8℃ in J and Y treatments respectively.S and D mulchings extended the vegetative growth under the effect of water and temperature increment,and advanced 11 days of whole growing period,while J mulching extended 3 days of growth period,there was no effect on whole growing period in Y mulching.S and D mulchings evidently（P〈0.05） increased ear length,ear diameter,kernels per row and dry biomass of shoot;Y mulching evidently（P〈0.05） increased hundred-kernel weight;J mulching evidently（P〈0.05） decreased ear length,kernels per row and hundred-kernel weight.Four mulchings reduced economical coefficient of corn to a different extent.S,D,and Y mulchings respectively increased yield by 26.9%（P〈0.05）,34.7%（P〈0.05）,and 2.4%,J mulching decreased yield by 10.5%.