山东省花生种植区耕层土壤残膜赋存特征

通过对山东省花生典型种植区耕层土壤地膜残留量分布特征及影响因素的调查研究,准确评估花生种植农田系统地膜残留污染现状,为该地区农田地膜污染防控措施的提出提供科学依据。选择覆膜年限为1～15 a的18个农田为研究对象,调查土壤质地、地膜使用情况等指标,同时分析不同耕层土壤中地膜残留量和残片数量。结果表明,覆膜1～15 a的4个典型花生种植区耕层(0～30 cm)土壤残膜量在2.48～46.01 kg·hm~(-2),不同区域间差异不明显,均低于我国农田残留量限值。随着覆膜年限的增加,耕层土壤中残膜的含量和数量均呈逐年上升趋势。残膜含量和残片数量随土壤深度增加而逐渐降低,分布在0～10 cm土层内的残膜显著高于10～20 cm和20～30 cm土层,随着覆膜年限增加,残膜呈现向深层土壤下移的趋势。25、4～25 cm~2和4 cm~2残片数均随土壤深度的增加而降低。随覆膜年限增加,耕层(0～30 cm)土壤中小面积残膜数量和比例不断提高,且在20～30 cm深层土壤4 cm~2的小残片呈明显增多趋势,加大了长期覆膜农田的残膜回收难度,可能对耕层土壤环境造成长期影响。因此,采取适当措施增加地膜回收,以减少该地区地膜污染,对保护该地区花生产地健康有积极作用。

Occurrence characteristics of residual film in cultivated soil of peanut planting area in Shandong Province, China

The distribution characteristics and influencing factors of residual film amounts were investigated to accurately evaluate regional plastic film pollution in the peanut cultivated farmland system of Shandong Province, which can provide a scientific basis for preventing and reducing of farmland plastic film pollution in this area. The soil texture, use of plastic film, and other indicators were investigated in 18 farmland samples with 1~15 years of film mulching. The amount and quantity of residual film in different soil layers were analyzed. Results showed that the amount of residual film was 2.48~46.01 kg·hm^-2 in the soil layers(0~30 cm) of four typical peanut planting areas in Shandong Province, lower than the limit of residual film in China. The difference was not as evident among different areas. The quantities of residual film increased with the increase of film mulching years. The residual films were mainly found in the 0~10 cm soil layer, significantly higher than that in the 10~20 cm and 20~30 cm soil layers. The amount of residual film significantly decreased with the increase in depth; the residual film tended to move into deep soil with the increase in film mulching years. The film quantity residuals >25 cm², 4~25 cm², and <4 cm² significantly decreased with soil depth. The quantity and ratio of small residuals increased with the increase in mulching years; in particular, the film residuals <4 cm² increased in the 20~30 cm soil layer, making it difficult to recover film residue in long-term mulched farmland; this may have long-term effects on the soil environment. Therefore, mitigation measures should be taken to increase the recovery of plastic film to reduce plastic film pollution, which can play a positive role in protecting the health of peanut production in this region.