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近赤道低纬度地区孟加拉湾属于大陆边缘深海环境，该区的古生产力研究对于了解低纬度地区古气候演变及其对全球气候变化的响应具有重要意义。通过对研究区４个活塞岩心δ１３Ｃ值、高生产力指示种的含量变化、浮游有孔虫与底栖有孔虫丰度、Ｕ＋Ｂ指数等方面的研究发现，研究区受冰川－气候旋回作用影响明显，古生产力波动强烈。冰期时，陆源营养物质供应充分导致生物生产力增大，因而末次冰期最盛期氧同位素第２期时生产力最高，间冰期氧同位素第１、５期时生产力较低。该区氧同位素第３期也出现高生产力的情况，可能与当时研究区气候不稳定有关。氧同位素第３期强烈的西南季风活动使研究区淡水输入增强，进一步增加了冷、暖期生物生产力的差异。
The Bay of Bengal at near-equatorial low latitudes belongs to the deep-sea environment on the margin of the continental margin. The study of paleocapacity in this area is of great significance for understanding the paleoclimatic evolution in low latitudes and its response to global climate change. By studying the δ13C value of four piston cores, the content of indicator species of high productivity, the abundance of planktonic foraminifera and benthic foraminifera, and the U + B index of the four piston cores in the study area, it was found that the study area was significantly affected by the glaciation-climate cycle The paleo-productivity fluctuates strongly. During the glacial period, the supply of terrestrial nutrients fully led to the increase of biological productivity. Therefore, the productivity of the second stage of oxygen isotope in the climax of the last ice age was the highest, and the productivity of oxygen isotopes in the first and fifth stages of interglacials was lower. The third phase of the oxygen isotope in the area also showed high productivity, possibly related to the climate instability in the study area at that time. The intense southwest monsoon activity of the third oxygen isotope in the study area enhanced the fresh water input in the study area and further increased the difference of biological productivity in the cold and warm phases.