Ocean primary productivity significantly affects CO2 exchange at ocean-atmospheric interface, and it is an important participant in global carbon cycle, and it plays essential significance in studying global environmental change. Bohai Sea, the largest inland sea in China, almost surrounded by land, terrestrial pollution is serious. Since the 1990's, the environment of Bohai Sea has deteriorated, red tides have occurred frequently and water eutrophication is serious. According to Eppley Vertically Generalized Production Model (VGPM) inversed MODIS net primary production (NPP) data, spatiotemporal changes of NPP in Bohai Sea from 2003 to 2016 are analyzed using remote sensing and GIS technology. Results show that the annual average NPP values showed a trend of slightly increase with some fluctuation from 2003 to 2016. The monthly average NPP values reach the maximum of 5136.70 mg·m-2·d-1 in August, and minimum of 677 mg·m-2·d-1 in January. The seasonal changes of NPP values are obvious. The NPP values are the highest in summer, lower in spring and autumn, and the lowest in winter. The highest NPP value in summer appears in 2010, with a value of 5022.01 mg·m-2·d-1.There are four high NPP value areas in Bohai: East Liaoning Bay, Bohai Bay, Laizhou Bay and Qinhuangdao Port, of which the NPP values of Laizhou Bay are the highest. The spatial distribution of NPP values in Bohai Sea shows a trend of decrease from near shore to far shore areas, and the lowest NPP value appears in Bohai strait. The area of NPP significantly increase accounts for 50.67% from 2003 to 2016, mainly located in Liaodong bay, Qinhuangdao ocean area and the middle of Bohai Sea. The area of significantly reduce accounts for 31.12%, distributed in Laizhou bay and Bohai bay. NPP in only 0.28% of area appears extremely significantly increase. The sea surface temperature in Bohai Sea does not change significantly from 2003 to 2016, and the average sea surface temperature is 13.11 ℃. The correlation between NPP and sea surface temperature in Bohai Sea was mainly negative. The research of NPP in Bohai Sea can provide an important scientific basis for the environment monitoring and oceanic resources development.%渤海是中国最大的内海,四周几乎被陆地包围,陆源污染严重.自上世纪90年代中后期,渤海赤潮频发,水体富营养化程度严重.以渤海为研究区,采用Eppley-VGPM垂向归纳模型及一元线性回归分析法,对2003—2016年渤海NPP的时空分布进行研究.结果表明:14年来,渤海NPP年均值存在一定波动性变化且整体呈小幅度上升趋势.NPP月均值以8月最高,为5265 mg·m-2·d-1,1月最低,为677 mg·m-2·d-1.NPP季节性变化明显,表现为夏季>秋季>春季>冬季,夏季NPP最高值出现在2010年,为5027 mg·m-2·d-1.空间分布上,渤海存在四大NPP高值区,分别为辽东湾、渤海湾、莱州湾和秦皇岛邻近海域,其中莱州湾NPP数值最高.2003—2016年间NPP显著增加的海域面积占50.67%,分布在辽东湾、秦皇岛邻近海域及渤海中部海域;显著减少的海域面积占31.12%,分布在莱州湾及渤海湾;仅有0.28%的海域NPP出现极明显增加;17.93%的海域NPP并无明显变化.渤海NPP空间分布呈由近岸海域向远海岸海域逐步降低的趋势,最低值出现在渤海海峡.2003—2016年渤海海表温度无明显变化,相对稳定,海表温度年平均值为13.11℃.渤海NPP与海表温度以低度相关和负相关为主.研究结果可为渤海海域环境质量监测、渤海资源合理开发利用及环境治理提供依据.
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