南海北部初级生产力遥感反演及其环境调控机制

Satellite and in situ observations of primary production in the northern South China Sea

选取VGPM模式对南海北部海域初级生产力进行反演,通过SeaWiFS和AVHRR提供的Chl a,K490,PAR和SST等遥感数据产品计算得到了模式所需的各项参数,结合现场实测数据对模式进行了修订和误差分析.在此基础上通过反演计算获得了南海北部海域7 a平均(1998～2004年)初级生产力逐月分布图像.研究结果表明,研究海域初级生产力(C)分布趋势为由沿岸带向陆架以及外海逐渐降低,其中沿岸带区高于400 mg/(m2.d),外海区大致在100～300 mg/(m2.d);初级生产力水平冬季最高[平均为608 mg/(m2.d)]、夏季最低[平均为292 mg/(m2.d)],春、秋季基本持平.控制初级生产力时空分布的因子主要有营养盐、温度、光照,其中又以季风和环流驱动下的营养盐变化对初级生产力的调控最为显著.

An improved VGPM model were developed and applied to estimate the primary production in the northern South China Sea. The parameters of the model were gained based on the remote sensing data（including Chl a, K490 and SST et al. ）provided by SeaWiFS and AVHRR. The model was modified according to the synchronous ship-measured data and the errors were estimated as well. Based on this improved model, the monthly mean of primary production in 7 years （1998 to 2004） in the northern South China Sea were calculated. Results show that the primary production（C） in the studied area gradually decrease from coastal zone [the mean 〉400 mg/（m^2 · d）] to deep sea [100~200 mg/（m^2· d）]. With respect to the seasonal variation, the daily average primary production in the whole study area is the highest in winter [608 mg/（m^2 · d）] and the lowest in summer [292 mg/（m^2 · d] and it is almost the same between spring and autumn. The main factors which affect the spatial temporal distribution of primary production are nutrients, temperature and PAR. , particularly nutrients which driven by monsoon circulation .