华北典型农区棉田土壤中地膜残留特点研究

The Residue of Mulching Plastic Film of Cotton Field in North China

以华北典型农区-河北省邯郸市作为研究对象,对不同覆膜年限棉田地膜残留状况进行了分析研究,力求揭示棉田土壤中残膜数量、形态的时空变化特点。结果显示,邯郸地区棉田地膜平均残留量在59.1～103.4kg·hm-2之间。土壤中残膜含量与覆膜年限有关,覆膜年限越久,残留量越高。连续覆膜2a、5a和10a的棉田中地膜残留量分别为59.1、75.3和103.4kg·hm-2,且土壤中的残膜数量分别为393万片·hm-2、544万片·hm-2和965万片·hm-2。残留地膜主要集中在表层土壤中,3个土层(0～10cm、10～20cm、20～30cm)中的残膜数量依次约占总量的75%、20%和5%。研究结果还显示覆膜时间越长,深层土壤残膜量越高。小块膜明显多于大块膜,3种不同面积大小(<4cm2、4-25cm2、>25cm2)的残膜片数分别约占总量的65%、30%和5%。

Handan in Hebei province was selected to investigate the status and the spatio-temporal pattern of residual mulching plastic film in the typical cotton field that was mulched with agricultural plastic film for different years. The paper＇s aim was to identify the spatio-temporal pattern of residual mulching plastic film. The results indicated that the average amount of residual plastic film in cotton field was from 59.1～103.4 kg·hm^-2, which increased with the increasing of mulched years. And the total amount of residual plastic film in cotton field were 59.1, 75.3 kg·hm^-2and 103.4 kg·hm^-2 for 2 years, 5 years and 10 years respectively. The total piece amount of residual plastic film in cotton field in 2 years, 5 years and 10 years were 3.93, 5.44 and 9.65 million per hectare respectively. Most of residual mulching plastic film was distributed in top soil, and the percentage of residual plastic film in three layers of soil （0～10 cm, 10～20 cm, 20～30 cm） were 75%, 20% and 5% respectively. With the mulched years increased, the amount of residual mulching plastic film in deep soil and small piece of residual mulching plastic film increased, and which percentages of three kinds piece of residual piece of mulching plastic film （〈4 cm^2, 4～25 cm^2, 〉25 cm^2） accounted for are about 65%, 30% and 5% respectively.