中文摘要：

对2008年夏季在西北冰洋172°~143.6°W的楚科奇海及其北部海区对粒度分级叶绿素a和初级生产力现场观测资料,对观测区的空间分布特征进行了研究。结果表明,观测海区表层叶绿素a浓度为0.013~19.367μg/dm3,平均值为0.677±2.2661μg/dm3,次表层水叶绿素a浓度高于其它水层。水柱叶绿素a浓度从高到低的分布为陆架区、波弗特海、海台区、海脊区、海盆区。R断面叶绿素a浓度8月高于9月。观测站初级生产力（C）为0.050~2.453 mg/（m3.h）,陆架区平均生产力高于海台区、海盆区、波弗特海以及海嵴区。浮游植物粒级结构表明,楚科奇海和波弗特海区以大于20μm的微小型浮游生物占优势,对总叶绿素a浓度和初级生产力的贡献率分别为51.75%和50.89%,北部深海区以小于2.0μm的微微型浮游生物的贡献占优势,其对总叶绿素a浓度和初级生产力的贡献率分别为68.25%和56.13%。

英文摘要：

Investigations of the size-fractionated chlorophyll a and primary productivity were carried out in the western Arctic Ocean during the 3nd national arctic research expedition of China during the summer of 2008.The results show that the surface chlorophyll a concentrations are 0.013~19.367 μg/dm3 and the average value is（0.677±2.2661）μg/dm3 in the surveyed area.Chlorophyll a concentrations in the subsurface water are higher than these at the surface layer and in the deep depth water.The distribution of chlorophyll a is obviously areal characteristics,the areal arrange order of the water-column chlorophyll a is the Chukchi shelf,the Beaufout Sea,the Chukchi Plateau,the Mendeleev Ride and the Canada Basin.The chlorophyll a concentrations decrease in two sequential samplings on Section R,with water-column average values of（3.083±3.009） and（0.797±0.774）g/dm3,respectively.The primary productivity at the surveyed stations is 0.050~2.453 mg/（μm3·h）.The primary productivity of the Chukchi shelf is higher than that of the Chukchi Plateau,the Canada Basin,the Beaufout Sea and the Mendeleev Ride.The results of the size-fractionated chlorophyll a and primary productivity show that microplankton accounts for the majority of the total chlorophyll a（51.75%） and primary productivity（50.89%） on the Chukchi shelf and the Beaufout sea Shelf.The contributions of the picoplankton account for the majority of the total chlorophyll a（68.25%） and primary productivity（56.13%） in the Beaufout Sea,on the Chukchi Plateau,the Mendeleev Ride and in the Canada Basin.