全膜双垄沟播玉米土壤含水率和温度及杂草去除效应

Soil moisture,soil temperature,weed control and yield effects of double ridge plasticfilm mulching in maize production

为了明确黑色地膜对全膜双垄沟播玉米土壤含水率、温度和杂草去除效应及玉米主要性状的影响,采用田间试验,研究了黑色地膜对全膜双垄沟播土壤含水率和温度及玉米主要经济性状的变化规律。结果表明,黑色地膜有提高土壤含水率的作用,不同土层含水率表现为80~100cm>60~80cm>0~20cm>40~60cm>20~40cm;黑色和白色地膜覆盖下,各土层土壤含水率均呈单峰型消长动态,但黑膜的波动幅度均小于白膜。黑色地膜有降低土壤温度的作用,不同土层温度表现为10cm>5cm>15cm>20cm>25cm;黑色和白色地膜覆盖下,各土层土壤温度均呈抛物线型消长动态,但黑膜的波动幅度均大于白色地膜。与白色地膜相比,全膜双垄沟玉米田覆盖的黑色地膜对阔叶杂草和禾本科杂草的株防效和鲜质量防效均达97%和99%以上,对玉米出苗率、成穗率、穗长、穗粗、秃顶等性状无明显影响,但对玉米株高、株高整齐度、生育期、产量有影响。黑色地膜不仅有助于提高土壤含水率、降低土壤温度和防除田间杂草,还对玉米的部分农艺性状有影响。

The double ridge plastic mulch cropping technique has been widely adopted since 2010 for maize and potato production across 8 provinces and autonomous regions of northeast,north and northwest China with lower rainfall.The plastic film blocks moisture evaporation from soil and channels precipitation into the sowing trench between the ridges,so increasing soil moisture level around the crop roots,as well as assisting with weed control and modifying soil temperature.Yields can be increased by up to 30% with considerable economic benefit.This research compared the performance of white（Control）and black plastic film as the soil cover,since there is little available data on whether plastic film color affects the soil moisture and temperature beneath,and crop performance.In this research soil moisture and temperature were measured weekly over the growing season from early April to mid July,and weed biomass data,and crop agronomic and yield were collected on relevant dates.Soil moisture was measured for 5 soil depths：0-20,20-40,40-60,60-80,and 80-100 cm,and soil temperature for 5,10,15,20,and 25 cm soil depths.Typical values for soil moisture were18%-20%in April,20%-22%in May and 16%in June,without major variation across soil depths.In the 0-20 cm layer soil was 1%-2% drier under black film than under white film in April,but this gradually reversed and soil had 2% higher moisture content under black film in June.In the deeper soil layers（except 80-100 cm）,soil moisture（%）was identical under black and white film in April,but by June was 1%-2% higher under black film than white film.Soil temperatures ranged from 12-18 ℃ at the start of the experiment to25 ℃in June,and except for the 10 cm soil depth,were consistently lower under black film than white film by over 2 ℃in April,reducing to 0.5 ℃lower under black film in June.Weed densities in June were 150 and 3 plants/m2 under white film and black film,respectively.Crop agronomic data generally did not differ significantly with film color,but yield was 5.4%-9.5% higher when maize was planted on black film.