吉林省西部盐碱地5种林分类型土壤改良效果研究

为揭示吉林省西部盐碱地不同林分类型的土壤改良效果,以松原市乾安县分布的柽柳林、黑杨林、油松林、黑杨白榆混交林及枸杞林5种典型林分为研究对象,未造林地作为对照,通过野外调查与室内分析相结合,对各林分0~30 cm土层深度的土壤理化性质进行分析。结果表明：5种林分对土壤理化性质均有一定程度的改善,与未造林地相比,5种林分均表现为土容重减小,孔隙度增加,土壤渗透性能得到改善。各林分对0~10 cm表层盐碱土pH有明显的降低作用,与对照相比降低了3.69%~7.50%。林地土壤养分含量与未造林地相比有显著提升,各土层深度林地土壤有机质、全氮、水解氮、全磷、有效磷、全钾、速效钾含量均大于未造林地,土壤养分主要集中于0~20 cm土层深度,呈表聚现象。通过主成分分析法对14个土壤改良评价指标进行综合评价,其综合得分由大到小依次为：枸杞(43.81)>柽柳(40.79)>黑杨白榆混交林(40.33)>黑杨(39.31)>油松(39.03)>未造林地(33.55)。结果表明5种人工林均能够改善土壤理化性质,在吉林省西部地区通过植被恢复进行盐碱地改良时,可考虑枸杞与柽柳为优选树种。

Soil Improvement Effect of Five Different Typical Forests in Saline-alkali Soil in Western Jilin Province

To reveal the soil improvement effect of different forest types in saline land of western Jilin Province, five types of typical forests distributed in Qian’an County, Songyuan City were selected as research objects, which were Tamarix chinensis forest, Populus × xiaohei forest, Pinus tabuliformis forest, Populus × xiaohei and Ulmus pumila mixed forest and Lycium chinense forest, respectively. Took the unplanted land as control, the physicochemical properties of soil in 0-30 cm were studied by the method of soil sampling and laboratory measurement. The results showed that: compared with the unplanted land, the physical and chemical properties of soil of the 5 kinds of forests were all improved to a certain extent. The soil bulk density decreased while the soil porosity increased. Soil infiltration capacity in different forest types was improved. The pH significantly decreased by 3.69% to 7.50% compared with the unplanted land in 0-10 cm soil layer. Soil nutrient content of forestland was significantly increased compared with the unplanted land. Soil organic matter, total nitrogen, available nitrogen, total phosphorous, available phosphorous, total potassium and available potassium content of forestland were higher than that of the unplanted land in every soil layer. Soil nutrient content mainly concentrated in 0-20 cm, showing obvious surface accumulation. Using principal component analysis to evaluate the 14 soil quality indicators, the comprehensive score of the 5 types of forests were listed in the sequence of Lycium chinense forest (43.81) > Tamarix chinensis forest (40.79) > Populus ×xiaohei and Ulmus pumila mixed forest (40.33) > Populus ×xiaohei forest (39.31) > Pinus tabuliformis forest (39.03) > CK (33.55). The five types of typical forests could improve soil physiochemical properties. Lycium chinense and Tamarix chinensis could be considered as the optimized tree species in the process of saline land improvement by restoring vegetation in western Jilin Province.