基于MODIS数据的福建海域近10年净初级生产力时空变化研究

Research on Spatio-Temporal Variation of net Primary Productivity in Fujian Waters in the Recent 10 Years Based on MODIS Data

利用GIS与RS软件技术,以垂向归纳模型(Vertically Generalized Production model,VGPM)反演的2003—2012年的120幅MODIS数据的月净初级生产力(Net Primary Productivity,NPP)数据为基础,分析近10a福建海域NPP的时空演变特征。结果表明,NPP空间分布呈闽北>闽中>闽南的高纬海区向低纬海区递减、近岸海域向较远海域递减趋势;闽南和闽中交界海域、闽北中部较远海域等出现明显低值区;NNP时序变化具有明显区域性:近、远岸NPP月均值变化在闽北、闽中海域差异明显,在闽南海域则较为一致。NPP月均值变化率呈现离岸线越远变化率越小,并随纬度降低而降低的态势,且其最大值落在I和II区;NPP季均值在近岸与远岸分别表现为夏季>春季>秋季>冬季与冬季>春季>夏季>秋季的特征;NPP年均值变化总体上表现出高低值年份交替的周期性特征。开展NPP研究可为海洋生态系统结构分析、渔业资源合理开发与可持续利用、海洋环境质量评价与预报等提供科学依据。

Using GIS and RS software technology the characteristics of spatio-temporal variation in Fujian waters in the recent 10 years are analysed based on the MODIS NPP data of 120 months from 2003 to 2012 which are retried from VGPM model. The results showed that NPP spatial distribution trended to decrease as the latitudes decreasing（northern Fujian waters〉central Fujian waters〉southern Fuiian waters） and as it going away from near-shore to far-shore. There were obviously low NPP regions in the junction of southern and central Fujian waters, and in the far-shore of the center of northern Fujian waters. The tem- poral variation of NPP obviously presented regional characteristics, such as the change of monthly average NPP being appeared significant difference between near-shore and far-shore in northern and central Fujian waters but not in southern, the change rate of monthly average NPP being trended to decrease also as the latitudes decreasing and as it going away from near-shore to far-shore, maximum of it being appeared in I zone and II zone, quarter average NPP in the near-shore and far-shore being reflected summer〉spring〉 autumn〉winter and winter〉spring〉summer〉autumn respectively, in general the change of annual aver- age NPP being showed periodic characteristics of alternating high and low values year by year. The study on the NPP can offer scientific basis for the analysis of sea ecosystem structure, the reasonable exploitation and sustainable utilization of fishery resources, and the assessment and forecast of sea environmental con- dition.