东海区底层及近底层鱼类资源的空间异质性

Spatial heterogeneity of demersal fish in East China Sea.

运用空间自相关指数和变异函数分析东海区底层及近底层鱼类资源的空间自相关性和空间变异 .其空间分布平均场的Gearyc和MoranI指数分别为 0 38和 0 5 2 ,各向同性随机变异占总变异的5 9 9% ,表明其空间分布具有中等自相关特性 ,空间变异中由随机引起的变异大于由空间相关尺度过程引起的变异 ;各方向变异属于几何异向性 .资源密度的年际变化与C、C0 和C +C0 均呈正相关 ,说明年际平均密度的增加由空间自相关变异和随机变异共同引起 。

Quantitative analysis for the spatial distribution of fish is one of the important methods in fishery or fish ecology research.In this paper,the indexes Geary c and Moran I for the density distribution of demersal fish were calculated,and the semivariograms were drawn.The values of Geary c and Moran I were 0.38 and 0.52,respectively,and the C 0/C 0+C was 59.9%,which meant that the distribution had a medium spatial autocorrelation with anisotropy,and the heterogeneity caused by random was a little higher than that caused by spatial autocorrelative process.The annual fluctuation of density was caused by the spatial autocorrelation and the random,because the density was significantly positively correlated with the values of C,C 0 and C+C 0,respectively.