發(fā)布時(shí)間：2019-05-15 10:45

【摘要】：露天煤礦的開采與開發(fā),會(huì)破壞地形地貌,毀壞植被,減少生物多樣性,造成水土流失等。開采露天煤礦所形成的排土場,是由大量煤礦開采剝離物以及棄土棄渣堆砌而成的一種巨型人工地貌。露天煤礦開采改變地形地貌,破壞地表徑流,而該區(qū)域年降雨量少且降雨集中,水成為限制排土場上的植被恢復(fù)的主要因素。通過對礦區(qū)排土場不同植被恢復(fù)模式下土壤水分特性的研究,可以探究不同植被模式下土壤的恢復(fù)狀況,并結(jié)合當(dāng)?shù)貙?shí)際狀況,以選擇出適合當(dāng)?shù)氐闹脖换謴?fù)模式,通過對添加砒砂巖、粉煤灰對排土場土壤水分特性的影響進(jìn)行研究,比較不同處理土壤的水分物理性質(zhì),探究最適合的添加比例,為礦區(qū)植被恢復(fù)與土地復(fù)墾提供支持。本文以黑岱溝露天煤礦東排土場為研究對象,選取排土場平臺(tái)上草地(苜蓿)、灌木林地(沙棘林地)、喬灌混交林地(楊樹×沙棘)、喬木林地(楊樹林地)四種植被恢復(fù)模式,并以排土場外選擇的自然恢復(fù)下的草地(荒草地)、灌木林地(沙棘林的)為對比,研究植被恢復(fù)對排土場土壤水分物理特性的影響。將砒砂巖、粉煤灰與排土場按照一定比例充分混合,研究砒砂巖、粉煤灰對排土場土壤水分物理性質(zhì)的改良作用。取得以下主要結(jié)果:(1)黑岱溝東排土場土壤物理性質(zhì)較差,其中容重平均為1.51g/cm3,總孔隙度平均為42.39%,毛管孔隙度平均為39.31%,非毛管孔隙為3.39%,遠(yuǎn)低于耕層50~56%,非毛管孔隙狀況8~10%的要求,飽和含水量平均為28.51%,田間持水量平均為24.18%。(2)不同植被恢復(fù)模式下,土壤的物理性質(zhì)有所差異。喬木地土壤容重平均為1.58g/cm3,最接近新建排土場,喬灌混交林地最小,為1.47g/cm3;喬灌混交林地的非毛管孔隙度最高為4.35%,喬木地最低,為2.74%,但都低于新建排土場;喬灌林地的飽和含水量最高為29.56%,最低為喬木地的26.13%。(3)Gardner模型對不同植被恢復(fù)模式下土壤水分特征曲線和砒砂巖、粉煤灰改良后土壤的水分特征曲線擬合度較高,R2最低為沙棘地(0.9311),最高為L1F1S1(0.9929)。(4)不同植被恢復(fù)模式下排土場土壤持水性為排土場草地自然草地排土場灌木地排土場喬灌混交林地自然灌木地排土場喬木地;土壤供水性的順序?yàn)樽匀徊莸刈匀簧臣磐翀鰡坦嗷旖慌磐翀霾莸嘏磐翀龉嗄镜嘏磐翀鰡棠镜�。從改善土壤水分特性�?排土場上的植被恢復(fù)模式,應(yīng)優(yōu)先選擇草地。(5)砒砂巖、粉煤灰都可增加排土場土壤的持水性,且添加比例越高,土壤持水性越強(qiáng)。僅加入砒砂巖后會(huì)導(dǎo)致土壤供水能力的下降。但給土壤加入同等比例的砒砂巖和粉煤灰混合物,即三者比例為1:1:1時(shí),土壤供水性和持水性最強(qiáng)。
[Abstract]:The mining and development of opencast coal mine will destroy topography and landform, destroy vegetation, reduce biodiversity, cause soil and water loss and so on. The dump formed by mining opencast coal mine is a kind of huge artificial landform, which is made up of a large number of coal mine stripping materials and abandoned soil and slag. Open pit coal mining changes the topography and landform and destroys the surface runoff, but the annual rainfall in this area is less and the rainfall is concentrated. Water has become the main factor restricting the vegetation restoration on the dump. Through the study of soil moisture characteristics under different vegetation restoration models in mining area dump, the soil restoration status under different vegetation models can be explored, and combined with the local actual situation, the suitable vegetation restoration model can be selected. Through the study of the effect of adding soft rock and fly ash on the soil moisture characteristics of the dump, the physical properties of soil moisture in different treatments were compared, and the most suitable adding ratio was explored, which provided support for vegetation restoration and land reclamation in mining area. In this paper, the east dump of Heidaigou opencast coal mine is taken as the research object, and the grassland (Medicago sativa), shrubs (seabuckthorn forest) and Joe irrigation mixed forest (poplar 脳 seabuckthorn) on the platform of the dump are selected. There are four vegetation restoration models in Arbor forest land (poplar forest land), and the grassland (wasteland) and shrubby forest land (seabuckthorn forest) selected outside the dump are compared. The effect of vegetation restoration on the physical properties of soil moisture in dump was studied. The physical properties of soil moisture in soft rock and fly ash were studied by mixing soft rock, fly ash and dump in a certain proportion. The main results are as follows: (1) the soil physical properties of Heidaigou East dump are poor, in which the average bulk density is 1.51 g 鈮，

本文編號：2477442