Distribution pattern of living resources is spatial scale-dependence, therefore an inappropriate scale may produce misleading results. As a key species in the Antarctic ecosystem, distribution of Antarctic krill (Euphausia superba) demonstrates significant spatial-temporal heterogeneity. The distribution pattern of this species is spatiotemporal complex and cannot be predicted effectively. In order to understand the spatial-temporal distribution pattern of krill resource in the Antarctic Peninsula, an important ecological and commercial-interested regions, the Moran's I value of krill density distribution was calculated at 12 spatial scales (5'×5' - 60'×60') by 5' grid of latitude and longitude. The results showed that the spatial pattern of krill is differed in spatial scales. The distribution of krill density showed a discrete trend at the 25'×25' scale, but the distribution of krill density showed a clustering trend at the other 11 spatial scales. According to the correlogram between the Moran's I value and spatial scale, the characteristic spatial scales of krill density distribution were determined as about 25'×25', which was determined by the Moran's I value inter-crossing the x-axis for the first time, and 15'×15', which was determined by the smallest scale with no significant difference between the Moran's I value and zero in the correlogram, respectively. This study showed that the method with no significant difference between the Moran's I value and zero value was more consistent with the characteristics of krill resource. It was, therefore, recommended that 15'×15' could be the optimum spatial scale for analyzing the distribution of krill density in this region.
Characteristic spatial scale of distribution for Antarctic krill (Euphausia superba) density in the Antarctic Peninsula
Número de documento:
WG-EMM-2021/32
Presentado por:
Professor Guoping Zhu
Aprobado por:
Dr Xianyong Zhao (China)
Punto(s) de la agenda
Resumen