苏北潮滩湿地植被对沉积物N、P含量的影响

文章对比分析了植被和沉积物中N、P垂向分布和季节变化,探讨不同植被对潮滩湿地N、P动态变化的影响。分析表明:潮滩湿地的分带性差异使N、P在潮滩湿地各地带有不同的分布规律和季节性变化特性,植被尤其是有较高地下生物量的互花米草和芦苇在整个潮滩湿地N、P的分布以及季节变化中起重要作用,潮滩植被主要是通过N、P在体内的主动转移,植物对沉积物中N、P的吸收以及富集死亡的地下根茎中分解矿化后释放的N、P来影响沉积物中N、P分布的; 1~4月通过枯落生物量回归到地面的N、P总量分别达到149.4 t和18.2 t,对整个湿地生态系统的生源物质循环以及生态环境产生很大影响。

Influence of Tidal Flat Plant on Contents of Nitrogen and Phosphorus in North Jiangsu Province

In this paper,the biomass of different plants in winter and spring are estimated.The contents and variations of N and P of plants,surface layer and core sediments in different ecological zones are also compared and analysized.Subsequently,the dynamic variations of N and P,which influenced by absorption,accumulation and transformation of different plants,are discussed.The results indicate that: for the zonation of tidal flat and different physiology construction of plants,the N and P show different distribution patterns and seasonal variations in different ecological zones;plants,especially perennial Spartina anglica and Phragmites communis with high ratio of aboveground and belowground biomass,play more important role in contents and seasonal variations of N and P in the whole tidal flat sediments;the main mechanism that the plant influence the sediment content of N and P include the active transformation of N and P in plant body,the absorption effect of plant,and the release of N and P from the decomposed and mineralized deceased belowground rhizome that accumulated in the belowground sediments;the quantities of N and P,returning to the ground with withering in different ecologic zones,reach 149.4 t and 18.2 t from January to April,and the biogeochemistry cycle and ecological environment of the tidal flat can be seriously affected.