库姆塔格柽柳沙包年层稳定碳同位素与气候环境变化

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 库姆塔格柽柳沙包年层稳定碳同位素与气候环境变化 DOI: 10.5846/stxb201210081381 作者: 作者单位: 甘肃农业大学草业学院,甘肃农业大学草业学院,甘肃农业大学草业学院,甘肃民勤荒漠草地生态系统国家野外科学观测研究站,甘肃省荒漠化与风沙灾害防治国家重点实验室,甘肃民勤荒漠草地生态系统国家野外科学观测研究站,甘肃省荒漠化与风沙灾害防治国家重点实验室,甘肃民勤荒漠草地生态系统国家野外科学观测研究站,甘肃省荒漠化与风沙灾害防治国家重点实验室,甘肃省荒漠化与风沙灾害防治国家重点实验室,甘肃民勤荒漠草地生态系统国家野外科学观测研究站 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然基金资助项目（40961013）；甘肃省自然基金资助项目（1208RJZA262） Climate environmental change and stable carbon isotopes in age layers of Tamarix sand-hillocks in Kumtag desert Author: Affiliation: Pratacultural College of Gansu Agricultural University,,,,,,,,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:采用年层环境分析法，建立库姆塔格沙漠柽柳沙包年层稳定碳同位素序列，并利用记录的环境信息和附近气象资料，分析柽柳沙包稳定碳同位素与气候环境变化。结果表明：（1）柽柳沙包年层稳定碳同位素比率（δ13C）在20世纪40-60年代出现波动，80年代后趋于下降，δ13C序列变化符合全球树轮δ13C下降趋势，表明大气CO2浓度增加会对柽柳沙包年层δ13C造成影响。（2）柽柳沙包年层稳定碳同位素分辨率（Δ）与全球气候变化趋势相一致，120a以来，全球气候变暖，柽柳沙包Δ偏重，为干热的气候环境，19世纪80年代以前，气温偏低，柽柳沙包Δ值偏轻，代表冷湿的气候环境。（3）不同生境环境下柽柳沙包年层Δ值对气候环境要素产生不同的响应，高海拔的山前柽柳沙包Δ值与年降水、湿度及季节性气压、光照相关性显著，Δ值受多个气候要素的影响，其滞后作用不明显；低海拔的干旱沙漠区柽柳沙包Δ值对年气温及季节性降水、湿度特别敏感，Δ值存在明显的滞后效应。 Abstract:Kumtag desert, China's sixth largest desert, lies in the south-east of the Lop Nur region,and is famous with the unique dune type of Pseudo-feathery dunes in the whole world. Kumtag desert is expanding and threatening to engulf previously productive lands with its arid wasteland character with the speed of 1-4 m eastward annually. Tamarix sand-hillocks is a frequent special biological landform types, with legible age layers structure composited by sand and plant litters, in Kumtag desert. And it is very important for regional environmental evolution research because of noting the desert environmental information diversification. In the present paper, we try to explore desert environmental change process of Kumtag desert based on stable isotope techniques collecting stable carbon isotope sample of Tamarix sand-hillocks from the different habitats and set up the stable carbon isotope series in age layers of four typical Tamarix sand-hillocks, proluvial landforms, wedland landforms,YaDan landforms and valley landforms, meanwhile environmental information and local meteorological data were collected as well. The results showed that the ratio of stable carbon isotope (δ13C), in age layers of Tamarix sand-hillocks, was fluctuated during 40-60 s of twenty century, and had declined since 1980s. The change tendency of stable carbon isotope series was accord with the stable carbon isotope downtrend of tree-ring all over the world. It was indicated that atmospheric CO2 concentration increasing affected the carbon isotope of stable carbon isotope (δ13C) in age layers of Tamarix sand-hillock. The resolution ratio(Δ)of stable carbon isotope in age layers of Tamarix sand-hillocks had a similar change trendency to the global climate changes. It was dry and warm climate environment in the recent 120 years, which the resolution ratio(Δ)was reduced with the global climate warming. However, the climate environment was colder and moister before the industrial revolution in the nineteenth century, and the resolution ratio(Δ)was rosen. There was different response of the solution ratio Δ of stable carbon isotope in age layers of Tamarix sand-hillocks under different habitats to climatic elements changes. In the high altitude area, the resolution ratio(Δ)in age layers was restricted by several climatic factors. e.g. air temperature, humidity, atmospheric pressure, etc. the resolution ratio(Δ) composition had significantly relationship with annual air relative humidity, annual precipitation, seasonal atmospheric pressure and seasonal illumination intensity. The resolution ratio(Δ)composition was affected by several climatic factors, but the hysteresis effect was not obvious. On the contrary, in the arid desert area in low elevation, the resolution ratio(Δ) composition had had greatly sensitivities to annual temperature, seasonal precipitation and seasonal air relative humidity, and the hysteresis effect was obvious. 参考文献 相似文献 引证文献