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本文通过分析龙感湖沉积物中的色素、孢粉、硅藻研究结果，探讨该区近3000年来环境气候波动特点．结果表明：3200一2400aBP，色素含量较高，与温度条件较好有关．该带孢粉浓度也最高，阔叶乔木树种花粉丰富，湿生及水生植物经常出现．总体上为相对暖湿阶段，其中仍有凉湿波动．2400－1600aBP，具体分为两个阶段，前期约2400－2000aBP．CD、TC、Myx含量明显较低，水生、湿生草本减少，气候偏凉干；后期各种色素含量均升高，与暧性木本属种增多相对应．表明气温有升高趋势．这一时期色素总体含量较上一阶段略低，与孢粉组合反映的气候温凉略湿特征一致．1600－1500aBP，该段CD、TC、Osc、Mry均为谷值．反映湖泊生物量减少，富营养化程度低，对比孢粉曲线其木本为谷值段，以禾本科为主，气候上反映为明显的降温事件．1500－1100aBP，CD、NC、TC、Osc及Myx含量均明显增大．湖泊生产力有所提高，反映了此时期气候好转，这也与孢粉资料吻合．1100－100aBP，整个阶段色素含量低，达到整个剖面的最低段．湖泊富营养化程度低，水质好转．而孢粉资料表明此阶段孢粉浓度低，针叶花粉增多，反映气温低，植被不发育，与色素结果对比较好．时段上相当小冰期．100aBP至今，各项色素含量明显增高，一方面反映湖泊的水体?
In this paper, through analyzing the research results of pigments, sporopollen and diatoms in the sediments of Longgan Lake, the characteristics of environmental climate fluctuation in the past 3,000 years are discussed. The results show that: 3200 a 2400aBP, pigment content is higher, and the temperature conditions are better. The belt pollen concentration is also the highest, broad-leaved arbor species rich in pollen, wet and aquatic plants often appear. Relatively warm and wet stage, which is still wet and cold fluctuations. 2400-1600aBP, specifically divided into two stages, the previous period of about 2400-2000aBP. CD, TC, Myx content was significantly lower, aquatic, wet herbs decreased, the climate is cooler; post-various pigment content increased, and the increase in the number of warm woody corresponding. Shows the trend of rising temperatures. The pigment content in this period was slightly lower than that in the previous stage, which is consistent with the slightly cool and humid climate reflected by the sporopollen assemblage. 1600-1500aBP, this section of CD, TC, Osc, Mry are trough. The decrease of biomass and eutrophication in lakes reflected the low level of eutrophication. Compared with the sporopollen curve, the woody biomass was mainly in the valley. 1500-1100aBP, CD, NC, TC, Osc and Myx were significantly increased. Lake productivity has improved, reflecting the climate change during this period, which also coincides with the sporopollen information. 1100-100aBP, the pigment content of the entire stage is low, reaching the lowest section of the entire section. Lake eutrophication is low, water quality improved. However, the pollen data indicated that the pollen concentration was low and the needle pollens increased at this stage, which reflected that the temperature was low, the vegetation was not developed, and the result of pigment was better. Quite a small ice period. 100aBP so far, the pigment content increased significantly, on the one hand reflect the lake’s water?