互花米草引种对苏北潮滩湿地 TOC 、TN和TP分布的影响

分析了TOC、TN和TP在苏北潮滩湿地不同生态带沉积物和植被中的分布状况,结果表明:TOC和TN的水平和垂向平均含量以互花米草滩为最高,其次分别为盐蒿滩、芦苇滩和光滩。TP的平均含量以光滩为最高,依次由海向陆逐渐减小。在生物量最大期间(秋季),单位面积上互花米草体内TOC、TN和TP的累积量远大于盐蒿和芦苇。互花米草主要通过以下4个方面对研究区潮滩湿地TOC、TN和TP的分布产生影响:(1)互花米草滩面较高的沉积速率;(2)互花米草对整个潮滩湿地不同植被分布格局的改变;(3)互花米草有着高生产力以及巨大的地下生物量;(4)互花米草的生长特性使其在生长过程中对磷的需求量很大。

The influence after introduction of Spartina alterniflora on the distribution of TOC, TN and TP in the national Yancheng rare birds nature reserve,Jiangsu Province,China

The influence,after introduction of Spartina alterniflora,on the distribution of TOC,TN and TP in tidal salt marshes in north Jiangsu Province,is analyzed.The result indicates that,the unit area accumulation of TOC,TN and TP within the depths of 0~20cm,as well as average horizontal and vertical contents of TOC and TN,in Spartina alterniflora marshes,are higher than those in other ecological zones,and decrease from Spartina alterniflora marshes to Artemisia schrenkiana marshes,Phragmiues auszradis marshes and silty marshes.While the highest average horizontal and vertical content of TP occurs in silty marshes,and the average content increases from land to sea. In autumn,the unit area accumulation content of TOC of Spartina alterniflora is 14.1 and 1.9 times that of Artemisia schrenkiana and Phragmiues auszradis,respectively.Similarly,the unit area accumulation content of TN of Spartina alterniflora is 32 and 1.6 times that of Artemisia schrenkiana and Phragmiues auszradis.The unit area accumulation of TP of Spartina alterniflora is also larger than that of Artemisia schrenkiana and Phragmiues auszradis,its content is respectively 56 and 3.9 times that of Artemisia schrenkiana and Phragmiues auszradis. The influences,after introduction of Spartina alterniflora,on the distribution of TOC,TN and TP in tidal salt marshes are:(1) The accumulating rate of Spartina alterniflora is high,which benefits the preservation of nutrient matter,and the increase of accumulation contents of TOC,TN and TP in the whole tidal salt marshes;(2) changes of plants distribution pattern in tidal salt marshes induced by Spartina alterniflora,accordingly heighten the accumulations of TOC,TN and TP in the whole ecosystem;(3)the high production and enormous belowground biomass of Spartina alterniflora,influence not only TOC,TN and TP cycling in the inner ecosystem,and the exchange between the adjoining ecosystem,but also accumulations of such three matters in the whole tidal salt marshes;and(4)Spartina alterniflora demands abundant P during growing process because of its vegetative characteristics,and the content of TP in sediment of Spartina alterniflora marshes is continuously decreased during its movement from land to sea.Therefore,the content of TP in silty marshes is higher than that in other ecological zones.