Effects of Re-vegetation on Herbaceous Species Composition and Biological Soil Crusts Development in a Coal Mine Dumping Site

Abstract

Despite the critical roles of plant species' diversity and biological soil crusts (BSCs) in arid and semi-arid ecosystems, the restoration of the diversity of herbaceous species and BSCs are rarely discussed during the process of vegetation restoration of anthropogenically damaged areas in these regions. In this study, the herbaceous plant species composition, along with the BSCs coverage and thicknesses, was investigated at six different re-vegetation type sites, and the natural vegetation site of the Heidaigou open pit coal mine in China's Inner Mongolia Autonomous Region was used as a reference. The highest total species richness (16), as well as the species richness (4.4), occurred in the Tree and Herbaceous vegetation type site. The species composition similarities between the restored sites and the reference site were shown to be very low, and ranged from 0.09 to 0.42. Also, among the restored sites, the similarities of the species were fairly high and similar, and ranged from 0.45 to 0.93. The density and height of the re-vegetated woody plants were significantly correlated with the indexes of the diversity of the species. The Shrub vegetation type site showed the greatest total coverage (80%) of BSCs and algae crust coverage (48%). The Shrub and Herbaceous type had the greatest thicknesses of BSCs, with as much as 3.06 mm observed, which was followed by 2.64 mm for the Shrub type. There was a significant correlation observed between the coverage of the total BSCs, and the total vegetation and herbaceous vegetation coverage, as well as between the algae crust coverage and the herbaceous vegetation coverage. It has been suggested that the re-vegetated dwarf woody plant species (such as shrubs and semi-shrubs) should be chosen for the optimal methods of the restoration of herbaceous species diversity at dumping sites, and these should be planted with low density. Furthermore, the effects of vegetation coverage on the colonization and development the BSCs should be considered in order to reconstruct the vegetation in disturbed environments, such as mine dumpsites in arid areas.

Researches in biological soil crust of China: A review

“…Huang等人 [110] 建立了受土壤水分驱动下 的固碳模型, 综合计算出藻类和藓类的结皮年际固 碳潜力. 水分(包括降水和非降水)决定了BSC固碳活 性 [114,116] , 而土壤含水量和有效湿润时间决定了BSC 的 固 碳 量 [106,107,117] , 水 分 也 是 BSC碳 释 放 的 驱动因 素 [50,97,109,111,113,118~120] ; 另外, 沙埋干扰抑制了BSC的 碳固定, 促进了碳释放 [110] , 但BSC的缺失也将导致 碳释放量显著增加 [121] .…”

“…死亡 [33] . 许多报道认为, BSC对维管植物的影响机制在于 BSC通过改变土壤性状(地表粗糙度、土壤温度、湿 度、养分含量等)来影响维管植物的种子萌发、定居 和存活 [150,157~163] , 并改变了浅层土壤的水分含量, 导 致植被组成中浅根系的草本物种丰富度和生物量增 加, 深根系的木本植物盖度和生物量降低, C 4 植物增 加 [117,133,164,165] . 166~168] , 增加了昆虫多样性 [149] .…”

Composition and structure of soil fauna community in the Dexing Copper Mine tailings pool after revegetation

“…In pure tailing sand, the ability to maintain soil moisture and fertility is poor; the contents of nitrogen, phosphorus, potassium, and organic matter are extremely low; and the contents of heavy metals (such as copper) are too high; therefore, its habitat is very bad for the growth of plants (Ge et al, 2001;Monterroso et al, 2014). However, after revegetation restoration, tailing sand could be quickly covered by plants that could reduce the evaporation of soil water and could regulate the soil temperature and moisture (Berndtsson et al, 1996;Mukhopadhyay et al, 2016;Zhao et al, 2016). The soil quality could then be gradually modified (Zhang et al, 2014) and could promote the better growth of plants (Li et al, 2016), while the activities of soil microbes and soil fauna are also enhanced (Cristescu et al, 2012;Escobar et al, 2015;Nelson et al, 2015;Xie et al, 2015), which directly results in changes in the structure of the soil fauna (Topp et al, 2001;Yang and Gao, 2001;Cristescu et al, 2012).…”

“…Therefore, for ecological restoration and reclamation of land of the tailings pool, the pollution should be controlled. The restoration of the vegetation of tailing sands, using improved technology, is the only way for ecological restoration of the tailings pool (Wang et al, 2004;Wang et al, 2012;Chen et al, 2016;Zhao et al, 2016).…”

Successful lichen translocation on disturbed gypsum areas: A test with adhesives to promote the recovery of biological soil crusts

“…geomorphology and plant cover), BSCs are normally ignored. Limitations such as the slow growth of their components, low reproduction rates, the destruction of propagules and habitat together with the lack of a clear restoration methodology make the recovery of BSCs especially challenging3101314.…”