露天煤矿排土场不同培肥方式对沙棘人工林林下植被多样性的影响

EFFECTS OF DIFFERENT FERTILIZATION METHODS ON UNDERSTORY VEGETATION DIVERSITY OF SEA-BUCKTHORN PLANTATION

为探究黑岱沟露天煤矿新成排土场不同培肥方式对人工沙棘林林下植被多样性的影响规律。对复垦3年,采用5种不同培肥方式的沙棘人工林进行野外调查与土壤理化性质测定,与对照相比分析不同培肥方式对土壤理化性质、人工林植被生长以及林下植被多样性的影响。结果表明:接菌处理能显著提高土壤有机质和全氮含量,相比于对照提升幅度分别为67.56%和75.90%,绿肥降低了土壤有机质和全氮的积累,风化煤仅能够提高土壤有机质含量;所有培肥处理均显著降低了土壤速效钾和速效磷含量,不同培肥处理之间土壤pH和电导率无显著差异。接菌处理能够显著提高沙棘的株高和地径,与对照相比,沙棘的株高和地径分别提高了11.77%和21.63%;在植物净光合速率方面同样表现为接菌处理最高。群落相似性分析表明,接菌能够对植被群落产生较大干扰,相似系数最小的为接菌处理和对照、接菌处理和绿肥处理、接菌+绿肥处理和绿肥处理以及接菌+绿肥处理和绿肥处理,均为0.67。接菌处理显著提高了群落的多样性指数和丰富度指数,降低了群落的优势度指数。冗余分析表明,接菌处理对提高林下植被多样性效果最佳,其主要通过改变土壤养分含量和改变沙棘地上部特征2方面来影响林下植被的多样性特征。露天煤矿排土场生态修复需要人工植被种植与自然群落演替共同作用,探究露天矿排土场不同培肥方式对沙棘人工林林下植被多样性的影响规律对矿区群落恢复与生态重建具有重要的参考价值。

In order to explore the effect of different fertilization methods on the underfores vegetation diversity of artificial seabuckthorn forest in Xincheng dump of Heidaigou open-pit coal Mine.The field investigation and soil physical and chemical properties of Seabuckthorn plantation were carried out after 3 years of reclamation with five different fertilization methods.The effects of different fertilization methods on soil physical and chemical properties,vegetation growth and understory vegetation diversity were analyzed compared with the control.The results showed that the soil organic matter and total nitrogen contents were significantly increased by inoculation,67.56%and 75.90%compared with the control,respectively.The accumulation of soil organic matter and total nitrogen was decreased by green manure,and only soil organic matter content was increased by weathered coal.The contents of available potassium and available phosphorus in soil were significantly decreased in all fertilization treatments,but there were no significant differences in soil pH and electrical conductivity among different fertilization treatments.Compared with the control,the plant height and ground diameter of Seabuckthorn increased by 11.77%and 21.63%,respectively.The net photosynthetic rate of plants was also the highest in the inoculation treatment.Community similarity analysis showed that inoculation could cause great disturbance to vegetation community.The lowest similarity coefficient was 0.67 for inoculation treatment and control,inoculation treatment and green manure treatment,inoculation plus green manure treatment and green manure treatment,and inoculation plus green manure treatment and green manure treatment.Inoculation significantly increased the diversity index and richness index of the community,and decreased the dominance index of the community.Redundancy analysis showed that inoculation had the best effect on increasing the diversity of understory vegetation,which was mainly affected by changing soil nutrient content and changing the aboveground characteristics of sea-buckthorn.The ecological restoration of opencast mine dump requires the joint action of artificial vegetation planting and natural community succession.It is of great reference value to explore the influence law of different cultivation methods of opencast mine dump on understory vegetation diversity of sea-buckthorn plantation for mining community restoration and ecological reconstruction.