中国中温带东部生态地理区划的土壤指标

Eco-geographic regional system is formed by division or combination of natural features based on geographic relativity and comparison of major ecosystem factors (including biological and non-biological) and geographic zonality. In previous studies, soil types were often taken as a basis for soil regionalization. However, the quantitative characteristics of soil indicators are fitter than the qualitative ones of soil types for modern regionalization researches. Based on the second China’s national soil survey data and the provincial soil resource information, by principal analysis and discriminant analysis, this paper discusses the appropriate soil indicators as the complement of eco-geographic region indicator systems and the relationships between these soil indicators and soil types in regionalization. The results show that five indicators are used in eco-geographic zonality in mid-temperate zone of eastern China which are organic matter content, cation exchange capacity, pH, clay content and bulk density in topsoils. With a regression-kriging approach, the maps of soil indicators in mid-temperate zone of eastern China are compiled with a resolution of 1 km in every grid and the indicative meanings of these soil indicators are discussed. By cluster analysis it is proved that these soil indicators are better than the soil types and soil regionalization in delineating eco-geographic regions. Foundation: National Natural Science Foundation of China, No.40771016 Author: Liu Ye (1980–), Ph.D, specialized in integrated physical geography.     

中国西南纵向岭谷区孢粉空间组合对阻隔作用的指示意义

35 surface soil samples and 28 profile soil samples were collected in Longitudinal Range-Gorge Region, Southwest China. The distribution of pollen and spores and their relationship with the environment are analyzed. The results show that there are significant differences in pollen and spores taxa, amounts, dominant taxa and florae between the eastern and western flanks of the Ailao Mountain. There are more pollen and spores taxa, a greater amount and complexity on the western flank of the mountain than those on the eastern flank, while the dominant taxa are more centralized and prominent on the eastern flank of the Ailao Mountain. As for the plant florae distribution, there are significant differences in the number of taxa and composition between the eastern and the western flanks. The analysis of profile pollen and spores assemblage shows that its trends of variation are basically in accordance with the surface pollen and spores, which are also indicators of the environmental differences between the two flanks of the mountain. These significant spatial differences of pollen and spores are very close to the regional topography and climate difference. The mountain running perpendicular to the moisture-laden air flow serves as a barrier and the monsoon circulations the east and the west of the mountain result in different energy-moisture characteristics. We conclude that the main patterns of the pollen and spores can be attributed to the environmental differences.     

气候变化和水的最新科学认知

政府间气候变化专门委员会（IPCC）于2008年4月8日正式通过了"气候变化和水"技术报告。该报告建立在IPCC 3个工作组第四次评估报告的基础上,客观、全面而审慎地评估了与水有关的气候变化以及对水的过去、现在和未来的认知。最重要的进展是：过去几十年观测到全球变暖已经与大尺度水文循环的大规模变化联系在一起;气候模型对21世纪的模拟结果一致显示出降水在高纬和部分热带地区将增加,而在部分亚热带和中低纬地区将减少的结果;预计到21世纪中期,河流年平均径流和水量可能会因为高纬和部分湿润热带地区的气候变化而增加,而在中低纬和干旱热带将可能减少;许多地方降水强度和变率的增加将使洪旱危险性上升;预计冰雪储藏的水的补给将在本世纪减少;预计较高的水温和极端变化,包括洪旱等,将影响水质并加剧水污染;对全球而言,气候变化对淡水系统负面影响将超过收益;预计由于气候变化导致的水量-水质变化将影响食物的产量、稳定性、流通和利用;气候变化影响现有水的基础设施的功能和运行,包括水电、防洪、排水、灌溉系统,同时影响到水的管理;目前的水管理措施不足以应对气候变化的影响;气候变化挑战"过去水文上的经验能得到未来的情况"的传统说法;为保障平水和干旱情况所设计的适应选择,必须综合需水和供水双方的战略;减缓措施可以降低升温对全球水资源的影响程度,进而减低适应的需求;水资源管理明显地影响到很多其他政策领域。     

近40年青藏高原主要生物温度指标的变化趋势

以最热月均温、最冷月均温、≥0℃积温及其日数、≥5℃积温及其日数和≥10℃积温及其日数作为生物温度指标的代表,应用青藏高原地区1966~2005年共87个气象站点逐日观测资料,分析其变化趋势。结果显示:最热月均温与最冷月均温整体均呈上升趋势,而最冷月均温的上升幅度明显大于最热月均温的上升幅度,空间上两者呈非对称变化。≥10℃积温、≥5℃积温和≥0℃积温增幅依次增大,其日数的变化是,≥5℃积温日数增幅最大,≥10℃积温日数次之,≥0℃积温日数最小。总体而言,近40年来青藏高原温度变化为增加趋势,植被的最佳生态空间及生态地理区域界线可能会发生不同程度的变动,生态系统的结构和功能可能也需要进行相应的调整来适应温度的变化。     

“一带一路”区域气候变化事实、影响及可能风险

“一带一路”区域国家经济、政治发展极不平衡,随着全球气候变暖,区域内的自然环境、气候资源、水资源等都将面临着显著而复杂的变化,并且干旱、洪涝等多种气候灾害是“一带一路”区域可持续发展和重大基础设施建设面临的重大威胁之一。目前,“一带一路”倡议已经进入实质性建设阶段,沿线地区的气候变化及其灾害风险关乎“一带一路”倡议能否顺利实施及亚投行的投资安全。在此背景下,2016—2018年中国科学院地球科学学部实施了“‘一带一路’区域气候变化问题”咨询评议项目,项目针对该区域气候变化的事实、未来变化预估、气候变化的可能影响以及带来的潜在风险等问题进行了系统的调研,并开展了若干分析和研究。经过两年的努力,项目组完成了有关进展报告四份,包括一份总报告和三份分报告。本文扼要地概括和介绍了项目取得的主要成果。     

青藏高原的气候植被模型研究进展

气候植被研究是全球变化研究的重要内容, 而模型研究是气候植被研究的重要手段。青藏 高原以其特殊的自然环境特点, 形成了气候与植被独特的适应机制, 为许多通用气候植被模型所 不能反映, 加之所受到人类活动的干扰相对较少, 决定其为植被气候研究的重要实验场地。本文 回顾了气候植被模型发展的相关历程, 评述了每类模型的特点及其不足。从植被格局研究和植被 生产力研究两个方面, 对青藏高原的气候植被研究进行了总结和分析, 认为模型研究是气候植被 研究的重要手段, 而青藏高原的研究在这方面还比较落后, 同时对青藏高原气候植被模型研究中 存在的一些问题, 如数据精度、模型的适宜性和结果验证等进行了讨论。认为今后青藏高原气候 植被模型研究的重点应是进一步明晰气候植被的关键过程, 立足高原环境特点开发有高原特色 的气候植被模型。     

中国干湿格局对未来高排放情景下气候变化响应的敏感性

气候变化影响下干湿状况的区域分异格局如何变化是一个重要科学问题。基于参与耦合模式比较计划第五阶段(CMIP5)的5个全球气候模式(GCM),预估了RCP 8.5情景下未来百年中国干湿区面积的变化趋势,分析了干湿格局变化的敏感地区以及对气候变化响应的敏感性。结果表明:未来干湿格局变化以湿润区显著减少、干湿过渡区显著扩张为主要特征,特别是半湿润区面积在远期(2070-2099年)相对基准期(1981-2010年)增加了28.69%。升温2℃～4℃条件下,全国发生干湿类型转变的面积从10.17%增加至13.72%,尤其在淮河流域南部,这里主要受未来潜在蒸散增加的影响,湿润区向南明显退缩从而转变为半湿润区。总体上,随着未来升温加剧,中国干湿格局对气候变化响应的敏感性将可能增强。     

基于景观格局的区域沙漠化程度评价模型构建

区域沙漠化程度评价对于防沙治沙具有重要意义。本研究在当前区域沙漠化程度评价方法中补充了在不同类型沙漠化土地空间分布的生态意义及其对区域沙漠化整体程度的影响因子,使其能评价各类沙漠化土地面积相等时几个区域的沙漠化程度。本文应用景观生态学原理,通过对空间分布差异而引起生态过程不同的理论分析,筛选出表征沙漠化土地空间分布生态意义的景观格局指数--聚集度,结合遥感与地理信息系统技术构建出区域沙漠化程度评价模型,并应用该模型对内蒙古浑善达克沙地六旗县的区域沙漠化程度进行了评价。结果对该各旗县不同时期的沙漠化程度的区分度较好,按沙漠化程度的不同,提出对正蓝旗的沙漠化要加强治理,对沽源县和太仆寺旗的沙漠化应采取预防措施的区域沙漠化防治对策。     

区域可持续发展中的环境伦理案例分析:不同社会群体责任

环境伦理是对人与自然之间道德关系的认知,在区域发展中构建可持续发展的环境伦理观是实现人与环境协调的核心内容。从区域发展的案例入手,从哲学层面分析区域发展中人与环境产生冲突的原因,构建区域可持续发展环境伦理观,明确不同利益主体应承担的环境伦理责任与义务,是实现可持续发展的必要内容。本文对云南省林浆纸一体化工程进行环境伦理探讨,分析了桉树种植的土地资源、生态效应、纸浆生产的环境影响、经济效益、利益流向等一系列问题;从环境伦理角度对林浆纸工程进行分析,提出了可持续发展环境伦理观建立和环境伦理规范,认为在利益冲突的形势下,应该遵循"非人类中心"的环境伦理准则,贯彻人地和谐的自然观,综合考虑生态安全原则、综合效益原则、公平原则、共赢竞争原则,采取综合思维方法,构建可持续发展的环境伦理观;分析不同社会团体在区域可持续发展建设中的环境伦理责任,提出了决策者群体、企业家群体、媒介群体、科学家群体、公众群体等在环境伦理意识、环境伦理责任、环境伦理义务等方面所应起到的作用。     

1971-2000年青藏高原气候变化趋势

Trends of annual and monthly temperature, precipitation, potential evapotranspi- ration and aridity index were analyzed to understand climate change during the period 1971–2000 over the Tibetan Plateau which is one of the most special regions sensitive to global climate change. FAO56–Penmen–Monteith model was modified to calculate potential evapotranspiration which integrated many climatic elements including maximum and mini- mum temperatures, solar radiation, relative humidity and wind speed. Results indicate gen- erally warming trends of the annual averaged and monthly temperatures, increasing trends of precipitation except in April and September, decreasing trends of annual and monthly poten- tial evapotranspiration, and increasing aridity index except in September. It is not the isolated climatic elements that are important to moisture conditions, but their integrated and simulta- neous effect. Moreover, potential evapotranspiration often changes the effect of precipitation on moisture conditions. The climate trends suggest an important warm and humid tendency averaged over the southern plateau in annual period and in August. Moisture conditions would probably get drier at large area in the headwater region of the three rivers in annual average and months from April to November, and the northeast of the plateau from July to September. Complicated climatic trends over the Tibetan Plateau reveal that climatic factors have nonlinear relationships, and resulte in much uncertainty together with the scarcity of observation data. The results would enhance our understanding of the potential impact of climate change on environment in the Tibetan Plateau. Further research of the sensitivity and attribution of climate change to moisture conditions on the plateau is necessary.