滇中湖泊现生孟氏螺蛳壳体稳定同位素变化对气候环境的响应研究
发布时间：2019-06-21 04:09
【摘要】：湖泊生物及其壳体对湖泊环境变化具有响应敏感、快速等特征,包含年际或季节性的气候变化信息,已成为古环境学与古湖泊学领域的研究热点之一。生物壳体同位素组成特征作为识别古环境、古气候的有效指标,已在众多湖泊研究中的得到了应用。选择同一种生物壳体对于认识同位素所代表的环境特征具有重要意义。本文选择滇中湖泊,如滇池、抚仙湖、星云湖、杞麓湖以及异龙湖,作为研究对象,通过对其湖泊孟氏螺蛳壳体及宿生水体的同位素组成测定,利用多指标、多变量分析方法,探讨了食物对生物壳体稳定同位素分馏的影响,并分析了现生生物壳体同位素组成与湖泊水质参数之间的关系,由此讨论了孟氏螺蛳壳体对区域温度、降水量等气候环境指标的响应机制。本文得出如下几点结论:1湖水氧同位素组成变化一定程度上受降水同位素组成和气温的影响;滇中湖泊现生孟氏螺蛳壳体δ~(13)C和δ~(18)O的值4月偏正,9月、11月和12月偏负,从生长层分析可以得出,螺层体螺层壳顶。异龙湖和杞麓湖孟氏螺蛳壳体碳稳定同位素之间的差异一定程度上受气候、水环境、食物等因素的综合影响。2壳体稳定同位素对其宿生水体的响应主要体现在孟氏螺蛳壳体碳同位素对电导率环境信息的反映,它们之间存在明显的负相关系,而对水温、pH水环境参数指标并没有明显的反映。孟氏螺蛳壳体稳定氧同位素对其宿生水体环境参数各项指标都没有发现良好的反映和录。3水草对孟氏螺蛳壳体稳定同位素的影响主要体现在水草δ~(13)C水草对孟氏螺蛳壳体氧同位素的影响、水草δ~(15)N水草对孟氏螺蛳壳体氧同位素的影响C/N比值对孟氏螺蛳壳体碳氧同位素的影响。水草干湿比值、碳含量和氮含量与孟氏螺蛳壳体同位素没有明显的相关性,表明这些指标对生物壳体没有重要影响。4区域降水量和降水同位素的组成直接影响湖泊水同位素组成与分馏,孟氏螺丝的壳体稳定同位素对水草稳定同位素敏感响应和高度相关,另一方面,气温通过调节湖泊流域内的水循环,控制水分的蒸发平衡以及湖泊水位,气温升高时,湖泊水富集重同位素。
[Abstract]:Lacustrine organisms and their shells have the characteristics of sensitive and rapid response to lake environmental change, including interannual or seasonal climate change information, which has become one of the research hotspots in the field of paleoenvironment and paleolacustrine. As an effective index to identify paleoenvironment and paleoclimate, the isotopic composition characteristics of biological shell have been applied in many lake studies. The selection of the same biological shell is of great significance for understanding the environmental characteristics represented by isotopes. In this paper, the central Yunnan lakes, such as Dianchi Lake, Fuxian Lake, Xingyun Lake, Qilu Lake and Yilong Lake, were selected as the research objects. By measuring the isotopic composition of the shell and the persistent water body of the lake, the influence of food on the stable isotopic fractionation of the biological shell was discussed by using the method of multi-index and multivariable analysis, and the relationship between the isotopic composition of the present biological shell and the water quality parameters of the lake was analyzed. The response mechanism of Mencius snail shell to regional temperature, precipitation and other climatic and environmental indexes is discussed. In this paper, the following conclusions are drawn: (1) the change of oxygen isotopic composition in lake water is affected to some extent by precipitation isotopic composition and air temperature, and the values of 未 ~ (13) C and 未 ~ (18) O in the existing Montellodes shell in central Yunnan are positive in April, negative in September, November and December. From the analysis of the growth layer, it can be concluded that the snail shell top of the snail layer can be obtained. To some extent, the difference between carbon stable isotopes of Mongol snail shell in Yilong Lake and Qilu Lake is affected by climate, water environment, food and other factors. 2 the response of shell stable isotopes to the environmental information of conductivity is mainly reflected in the reflection of carbon isotopes in the shell of Mongol snail shell to the environmental information of conductivity, and there is an obvious negative phase relationship between them, but there is no obvious reflection on the water temperature and pH water environment parameters. The stable oxygen isotopes of Mencius mandarin shell were not well reflected and recorded. 3 the effect of water grass on the stable isotopes of Mencius mandarin shell was mainly reflected in the effect of water grass 未 ~ (13) C water grass on oxygen isotopes of Montellostella mongolica shell, and the effect of water grass 未 ~ (15) N water grass on oxygen isotopes of Montellostella mongolica shell. The effect of C 鈮，
本文编号：2503776
[Abstract]:Lacustrine organisms and their shells have the characteristics of sensitive and rapid response to lake environmental change, including interannual or seasonal climate change information, which has become one of the research hotspots in the field of paleoenvironment and paleolacustrine. As an effective index to identify paleoenvironment and paleoclimate, the isotopic composition characteristics of biological shell have been applied in many lake studies. The selection of the same biological shell is of great significance for understanding the environmental characteristics represented by isotopes. In this paper, the central Yunnan lakes, such as Dianchi Lake, Fuxian Lake, Xingyun Lake, Qilu Lake and Yilong Lake, were selected as the research objects. By measuring the isotopic composition of the shell and the persistent water body of the lake, the influence of food on the stable isotopic fractionation of the biological shell was discussed by using the method of multi-index and multivariable analysis, and the relationship between the isotopic composition of the present biological shell and the water quality parameters of the lake was analyzed. The response mechanism of Mencius snail shell to regional temperature, precipitation and other climatic and environmental indexes is discussed. In this paper, the following conclusions are drawn: (1) the change of oxygen isotopic composition in lake water is affected to some extent by precipitation isotopic composition and air temperature, and the values of 未 ~ (13) C and 未 ~ (18) O in the existing Montellodes shell in central Yunnan are positive in April, negative in September, November and December. From the analysis of the growth layer, it can be concluded that the snail shell top of the snail layer can be obtained. To some extent, the difference between carbon stable isotopes of Mongol snail shell in Yilong Lake and Qilu Lake is affected by climate, water environment, food and other factors. 2 the response of shell stable isotopes to the environmental information of conductivity is mainly reflected in the reflection of carbon isotopes in the shell of Mongol snail shell to the environmental information of conductivity, and there is an obvious negative phase relationship between them, but there is no obvious reflection on the water temperature and pH water environment parameters. The stable oxygen isotopes of Mencius mandarin shell were not well reflected and recorded. 3 the effect of water grass on the stable isotopes of Mencius mandarin shell was mainly reflected in the effect of water grass 未 ~ (13) C water grass on oxygen isotopes of Montellostella mongolica shell, and the effect of water grass 未 ~ (15) N water grass on oxygen isotopes of Montellostella mongolica shell. The effect of C 鈮，
本文编号：2503776
本文链接：https://www.wllwen.com/kejilunwen/diqiudizhi/2503776.html
