气候变化对滇西北碧塔海流域景观演变的影响

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 气候变化对滇西北碧塔海流域景观演变的影响 DOI: 10.5846/stxb201407101407 作者: 作者单位: 西南林业大学 环境科学与工程学院 云南 昆明,西南林业大学/国家高原湿地研究中心 云南 昆明,西南林业大学 环境科学与工程学院 云南 昆明,云南省林业科学院 云南 昆明 作者简介: 通讯作者: 中图分类号: 基金项目: 云南省优势特色重点学科(生态学); 国家自然科学基金(U0933601); 云南玉溪森林生态系统定位研究站项目 Landscape evolution characteristics of the Bita Lake watershed over northwestern Yunnan province under the background of climate changes Author: Affiliation: Department of Environmental Science and Engineering,Southwest Forestry University,Southwest Forestry University, National Plateau Wetlands Research Center,Department of Environmental Science and Engineering,Southwest Forestry University,Yunnan Academy of Forestry 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:气候变化是景观演变的重要驱动力,高海拔地带生态系统对气候变化的响应较为敏感和迅速。选择地处青藏高原东南缘,受人为干扰相对较小的碧塔海流域为研究对象,利用1958-2011年气象资料以及1955、1974、1981、1994、2005和2011年6个年代的景观类型面积,采用气候倾向率估计、Mann-Kendall突变检验方法和Pearson相关系数等统计方法,研究了香格里拉县气候变化背景下碧塔海流域景观演变特征。结果表明:(1)1958-2011年来,滇西北香格里拉县多年平均气温为5.9℃,多年平均活动积温为2146.1℃,多年平均年极端高温为24.3℃,多年平均年极端低温为-18.6℃,多年平均降水量为631.7mm。气温、活动积温和年极端低温呈显著上升趋势,近54年来气温平均上升了1.94℃,升温速率远高于云南和全国水平。年极端高温和降水量呈增加趋势,但增加不明显。滇西北高原碧塔海流域背景气候呈现显著的变暖趋势。(2)1955-2011年来,碧塔海流域自然景观演变规律为草甸和灌草丛向有林地演变,气温、活动积温和年极端低温升高趋势与有林地景观面积的增加趋势大体一致,与草甸和灌草丛变化趋势相反。(3)气温、活动积温和年极端低温与碧塔海流域草甸、灌草丛和有林地的景观面积变化具有显著的相关性,是流域景观演变的主导气候要素,在草甸和灌草丛演变成有林地的过程中发挥着重要作用。极端高温和降水量对流域景观演变的作用相对较弱。 Abstract:Climate change is one of the major driving forces for landscape evolution. The ecosystem in high altitude area has the most sensitive and fast response to climate change. In this study, we focused on the Bita lake watershed of northwestern Yunnan located in the Shangri-la county and in the southeast margin of Three Rivers Parallel Area over Qinghai-Tibet plateau mountains. The study area with small anthropogenic interference, is the ideal area to identify the coupling relationship between climate change and landscape change. Based on the meteorological data from 1958 to 2011, and the landscape area indices of class level in the years of 1955, 1974, 1981, 1994, 2005, 2011, the characteristics of landscape evolution over the Bita lake watershed under the background of climate change were studied using climate tendency estimation method, Mann-Kendall mutation method and Pearson correlation coefficient method. The results were as follow: (1) The values of mean annual temperature, mean annual active accumulated temperature, mean annual extreme high temperature, mean annual extreme low temperature, average annual precipitation were 5.9℃, 2146.1℃, 24.3℃, -18.6℃ and 631.7mm from 1958 to 2011, respectively. The temperature, active accumulated temperature and annual extreme low temperature increased significantly in the Shangri-La of northwestern Yunnan, while the increases of annual extreme high temperature and precipitation weren't significant. The average temperature was elevated about 1.94 ℃ from 1958 to 2011, and the increasing rate was much higher than that in Yunnan and China. Active accumulated temperature and annual extreme low temperature were shown to be significant warming mutation trend with an increase of 167.1℃ and 3.4℃ after the mutation in the years of 1988 and 1986, respectively. (2) The mechanism of landscape evolution was in a succession from meadow and scrub-grassland to forestland in the Bita lake watershed from1955 to 2011. The rising trends of temperature, active accumulated temperature and annual extreme low temperature were consistent with the increasing trend of forestland landscape area, but were contrary to the decreasing trend of meadow and scrub-grassland landscape area. (3) Significant correlation was found between temperature, active accumulated temperature, annual extreme low temperature and natural landscape area of meadow, scrub-grassland and forestland from 1955 to 2011. When temperature,active accumulated temperature and annual extreme low temperature were increased quickly, the area of meadow and scrub-grassland was decreased, whereas the area of forestland was increased. Temperature, active accumulated temperature and annual extreme low temperature were the main driving factors of landscape evolution over the Bita lake watershed of northwestern Yunnan, while the ecological effects of annual extreme high temperature and precipitation on landscape evolution were relatively lesser. Climate warming was conducive to the growth of the watershed dominant tree, which played an important role in formation of a succession from meadow and irrigation grass to forestland in Bita lake watershed. 参考文献 相似文献 引证文献