黔北发电厂周边林地植物群落结构及土壤碳、氮、磷分布特征

Phytocoenose and Soil Nutrient Around Coal-Fired Power Plant in Mountainous Area

为探索山区火电厂对周边林地植物群落及土壤碳、氮、磷的影响,调查了贵州省黔北火电厂周边7个样方乔木层和灌木层的物种群落情况,并研究了所在样方林中、林缘与林外耕地表层土壤中全氮、碱解氮及有机质情况。结果表明:研究区域自然林地乔木树种主要以马尾松、侧柏、柳杉、喜树、青冈为主;灌木主要以悬钩子、荚蒾、野花椒、崖豆藤、火棘等为主;草本植物则主要以肾蕨、茅草、蒿类植物为主。黔北发电厂周边林地土壤肥力水平较高,土壤全氮、碱解氮及有机质土壤肥力等级均为Ⅰ级,全磷是土壤养分的主要限制因子。土壤碳、氮、磷及其化学计量特征之间表现为不同的相关性,全氮与全磷具有相反的同源相关性。林地土壤中全氮、碱解氮及有机质主要受到坡度、土壤质地、植物群落结构与补给的影响。

The effect of coal-fired plant on organic matter,nitrogen and phosphorus in forest soils in mountainous areas,plant community structure in seven forestry survey plots around the Jinsha coal-fired plant were investigated.Organic carbon,total nitrogen,alkali-hydrolyzable nitrogen and total phosphorus in surface soil samples collected at centre,edge and outside of forest alnds were analyzed as well.The results showed that the dominant tree species in study region were Pinus massoniana,Platycladus orientalis,Cryptomeria fortunei,Cedrus deodara,and Cyclobalanopsis glauca.Primary shrubby species were Rubus corchorifolius,Viburnum Linn.,Zanthoxylum simulans,Millettia nitida,and Pyracantha fortuneana.Herbaceous plants were Nephrolepis cordifolia,Imperata cylindrica and Acroptilon repens.The soil fertility level was higher in the surrounding forest soils of power plant.The level of soil total nitrogen,soil phosphorus and organic matter metthe grade I level,and the main limiting factor of soil nutrients was total phosphorus.Different correlations were observed among soil carbon,nitrogen,phosphorus and their stoichiometric characteristics,and there was an opposite relationship between the total nitrogen and total phosphorus.Soil total nitrogen,alkali-hydrolyzable nitrogen and organic matter contents were mainly influenced by slope gradient,soil texture,plant community structure and exogenous input.