黄土区露天煤矿不同复垦模式对土壤水稳性团聚体稳定性的影响

为了解不同复垦模式对土壤水稳性团聚体稳定性的影响,选择山西省朔州市安太堡露天矿排土场为研究区,采取典型小区调查的方法,分析了复垦21、22 a的4种混交林复垦模式(刺槐+油松、刺槐+榆树+臭椿、刺槐+柠条+沙棘、沙棘+榆树)、2种纯林复垦模式(刺槐纯林、沙棘纯林)以及复垦耕地的土壤水稳性大团聚体的含量、土壤团聚体的稳定率(WSAR)、几何平均直径(GMD)、平均重量直径(MWD)、破坏率(PAD),并通过和原地貌及未复垦地相应指标进行对比,来研究不同复垦模式对土壤水稳性团聚体稳定性的影响。研究结果表明:经多年复垦后,土壤水稳性团聚体的稳定性有了显著提高,在团聚体DR0.25(0.25 mm团聚体质量)、WSAR、MWD和GMD值上呈现出4种混交林复垦模式2种纯林复垦模式未复垦林地,以及林地内排耕地的总体趋势;土壤水稳性团聚体PAD值呈现出相反的排序。上述复垦模式中,刺槐+油松复垦模式下土壤水稳性团聚体的稳定性最好。土壤水稳性团聚体稳定性的评价指标中,DR0.25、WSAR、MWD与GMD之间相互呈极显著正相关,且均与PAD呈极显著负相关。该研究结果可为黄土区露天煤矿土地复垦及土壤重构提供一定依据。

Effects of different reclamation patterns on the stability of soil water-stable aggregates of an opencast mine in Loess area

To understand the effects of different reclamation patterns on the stability of soil water-stable aggregates, reclaimed dumps of the Antaibao opencast mine in Shuozhou, Shanxi Province, which is located in the northwest Loess Plateau of China, were chosen for this case study. Soils were sampled in four mixed forest reclamation patterns(Robinia pseudoacacia L.+Pinus tabulaeformis C., Robinia pseudoacacia L.+Ulmus pumila L.+Ailanthus altissima M., Robinia pseudoacacia L.+Caragana korshinskii K.+Hippophae rhamnoides L., Hippophae rhamnoides L.+Ulmus pumila L.);two types of pure forest reclamation patterns(Robinia pseudoacacia L. forest and Robinia pseudoacacia L. forest);the arable land. The original landform and un-reclaimed land were taken as control. The content of water-stable macro-aggre-gates, soil water-stable aggregates stability rate(WSAR), geometric mean diameter(GMD), mean weight diameter(MWD), and failure rate (PAD)were analyzed. The results showed that, after years of reclamation, the stability of soil water-stable aggregates has significantly im-proved.The values of DR0.25, WSAR, MWD, and GMD of aggregates ranked as:four mixed forest reclamation patterns>two pure forest recla-mation patterns>un-reclaimed land, forest land>arable land.The PAD values of soil water stable aggregates showed the opposite order. The stability of soil water-stable aggregates was the best under the Robinia pseudoacacia L.+Pinus tabulaeformis C. pattern. There was a signif-icant positive correlation among DR0.25, WSAR, MWD, and GMD in the evaluation indices of the soil water-stable aggregates, and they all had extremely significant negative correlation with PAD. These results can provide some basis for land reclamation and soil remodeling of opencast mines in Loess areas.