南渡江农业土壤中农药分布特征与生态风险评估

为摸清稻菜轮作土壤中农药(CUPs)残留特征与生态风险,采集海南岛南渡江流域稻菜轮作系统168个土壤样品,利用QuEChERS-超高效液相色谱-串联质谱(UPLC-MS/MS)检测土壤中25种CUPs残留水平,结合土壤因子与作物类型分析CUPs残留关键影响因素,以风险熵法评估其生态风险.结果表明,∑25 CUPs处于0...     

Temporal variations of CO2 concentration near land surface and its response to meteorological variables in Heihe River Basin, northwest China

Atmospheric CO2 concentration (CC) near land surface and meteorological variables have been measured at four sites,named Yeniugou (alpine meadow and permafrost), Xishui (mountainous forest), Linze (oasis edge) and Ejina (lower desert),respectively, in Heihe River Basin, northwest China. The results showed that, the half hourly CC at night was larger than in daytime,and the daily averaged CC was the largest in winter. The averaged CC of 932 d at the Linze was about 418 ppm, was about 366 ppm in the 762 d at the Ejina. In the same period from September 23 to November 9, 2004, the averaged CC was about 625,334, 436 and 353 ppm, at Yeniugou, Xishui, Linze and Ejina, respectively. The linear relationship between daily averaged CC and air temperature T was negative, between CC and relative humidity (RH) was positive. The linear CC-atmospheric pressure (A P) relationship was negative at the Linze and Yeniugou, was positive at the Ejina. The relationship between CC and global radiation R was exponent, and soil temperature Ts was negative linear, and soil water content was complex. The correlation between CC and wind speed was not existent.Using meteorological variables together to simulate CC, could give good results.     

黄河流域区域发展优势与经济带生成可能

基于进化经济学和进化经济地理学的理论,文章重点讨论了黄河流域的区域发展优势和建成黄河流域经济带的可能性。研究从黄河流域发展的历史出发,论证了黄河流域经济发展的区域地理学本性(nature)条件和现实可能性:第一,黄河流域经济发展的区域地理学本性条件是,该区域已经完成了农业经济建设,出现了遍在性的工业化和经济区人口聚集,特别是经过长期聚集,黄河流域已经形成了中国的人口密集带,形成了具有区域发展优势的中原城市群。第二,在分析黄河流域区域发展优势基础上,提出建成“大中原-黄河经济带”的可能性及其发展途径,即在生态保护的前提下,坚持地理环境的鲁棒性建设,坚持城市创新发展,坚持发展新型产业。第三,地区发展政策重点应该关注中原城市群的工业化-城市化发育和一体化产业链的形成,根据新经济地理学理论,提倡城市产业专业化方向,打破省界限制,发挥经济区的地缘结构优势,在空间上与环渤海经济带融合,完成黄河流域经济带高质量发展的战略构想。     

海河流域植物中碳的输出(或存留)量和土壤中的库存量

研究了海河流域地区植物中碳的输出量和土壤库存量。结果指出：不同作物－土壤系统中各种作物碳的输出量和归还量有很大不同,作物碳输出量一般为归还量的３－１７倍;海河流域地区不同子流域土壤中碳的库存量也有差异,以滹沱河子流域土壤碳的库存量最高,大清河子流域土壤中碳的库存量最低。     

基于DEMATEL的区域洪涝灾害恢复力影响因素及评价指标体系研究——以巢湖流域为例

影响洪涝灾害恢复力的因素众多且相互关联,识别和区分这些影响因素,找到因素间互相影响程度和因果关系,对于明确洪涝灾害恢复力关键因素,快速找到需要改善的因素具有重要意义。通过分析灾害恢复力的内涵,从自然维、社会维、经济维、技术维、管理维5个维度构建区域洪涝灾害恢复力的影响因素指标体系,应用DEMATEL方法分析区域洪涝灾害恢复力影响因素之间的关系,并以巢湖流域为例凝练出适合该区域的洪涝灾害恢复力评价指标体系,结果表明,一级指标中自然维、经济维对其他因素影响最为显著,二级指标中政府财政支撑能力、土地因子、地形因子对其他影响因素的影响最大;而一级指标中经济维和社会维与其他因素关系最为密切,二级指标中政府财政支撑能力、区域经济实力、土地因子处于核心的位置。从整体影响输出上看,一级指标中原因因素共有2个,分别为自然维、经济维,且以经济维为最,二级指标中原因因素有11个,涉及五个维度,包括所有自然维中因素,并以地形因子、政府财政支撑能力、灾害政策法规为重。一级指标中结果因素有3个,分别为管理维、技术维、社会维;二级指标中共有12个,以管理维中的因素为主,相比于原因因素,通过改善结果因素可以更直接的提高区域洪涝灾害恢复力的水平。     

塔里木盆地是新疆生物多样性保护的一个关键区域

在陈昌笃关于确定生物多样性保护关键区域的标准和在新疆境内初步提出了５个关键区域的基础上,根据塔里木盆地古老物种和国家珍稀、濒危物种较多、特有现象较发达及柽柳鹰植物十分丰富和分布有世界上面积最大在胡杨林,加之塔里木盆地生态系统极其脆弱、破坏严重等特点和现状,初步认为,塔里木盆地应是新疆生物多样性保护的一个关键区域。     

Impact of Changing Climate and Land Cover on Flood Magnitudes in the Delaware River Basin,USA

Changing climate and land cover are expected to impact flood hydrology in the Delaware River Basin over the 21st Century. HEC‐HMS models (U.S. Army Corps of Engineers Hydrologic Engineering Center‐Hydrologic Modeling System) were developed for five case study watersheds selected to represent a range of scale, soil types, climate, and land cover. Model results indicate that climate change alone could affect peak flood discharges by ?6% to +58% a wide range that reflects regional variation in projected rainfall and snowmelt and local watershed conditions. Land cover changes could increase peak flood discharges up to 10% in four of the five watersheds. In those watersheds, the combination of climate and land cover change increase modeled peak flood discharges by up to 66% and runoff volumes by up to 44%. Precipitation projections are a key source of uncertainty, but there is a high likelihood of greater precipitation falling on a more urbanized landscape that produces larger floods. The influence of climate and land cover changes on flood hydrology for the modeled watersheds varies according to future time period, climate scenario, watershed land cover and soil conditions, and flood frequency. The impacts of climate change alone are typically greater than land cover change but there is substantial geographic variation, with urbanization the greater influence on some small, developing watersheds.     

The Water‐Year Water Balance of the Colorado River Basin

Model‐estimated monthly water balance components (i.e., potential evapotranspiration, actual evapotranspiration, and runoff (R)) for 146 United States (U.S.) Geological Survey 8‐digit hydrologic units located in the Colorado River Basin (CRB) are used to examine the temporal and spatial variability of the CRB water balance for water years 1901 through 2014 (a water year is the period from October 1 of one year through September 30 of the following year). Results indicate that the CRB can be divided into six subregions with similar temporal variability in monthly R. The water balance analyses indicated that approximately 75% of total water‐year R is generated by just one CRB subregion and that most of the R in the basin is derived from surplus (S) water generated during the months of October through April. Furthermore, the analyses show that temporal variability in S is largely controlled by the occurrence of negative atmospheric pressure anomalies over the northwestern conterminous U.S. (CONUS) and positive atmospheric pressure anomalies over the southeastern CONUS. This combination of atmospheric pressure anomalies results in an anomalous flow of moist air from the North Pacific Ocean into the CRB, particularly the Upper CRB. Additionally, the occurrence of extreme dry and wet periods in the CRB appears to be related to variability of the Atlantic Multidecadal Oscillation and the Pacific Decadal Oscillation.     

基于生态元核算的长江流域横向生态补偿机制及实施方案研究

长江流域生态保护目前主要采取由中央政府主导的环境规制和专项整治模式,资金主要来源于财政转移支付。这些措施见效快、力度强,但监管成本高昂,激励机制不足,并且有可能扩大不同主体功能区之间的收入差距。现有的少数横向生态补偿协议存在适用范围有限、补偿依据单一以及微观主体难以参与等问题。本文试图构建适用于更大空间尺度且涵盖多种生态服务的综合横向生态补偿模式,以建立各地区公平分担保护成本的长效机制。首先,利用生态元的核算方法构建长江流域各类生态资源的本底数据库,测算各省（区、市）生态元总量和单位面积生态元的变化情况。其次,从概念、参与主体、补偿模式和实施效果等方面探讨了创建流域生态元缓解银行的构思及其实施机制。本文认为,流域生态无缓解银行方案有助于构建适用于长江流域的市场化生态补偿机制。     

基于系统保护规划理念的长江流域两栖爬行动物多样性保护优先区评价

目前,已有很多研究致力于讨论保护规划中整合保护效益和经济成本的重要性。为丰富解决该问题的思路,从系统保护规划理念出发,应用MARXAN模型软件对长江流域两栖爬行类生物多样性保护优先区进行了选择和评价。研究中共选择两栖物种54个,爬行物种73个作为指示物种,并按濒危性和特有性划分为5个类型。综合考虑每个类型的特定保护目标,以县域人均GDP为相对保护成本,探讨如何选择达到保护目标的最低经济成本区域。通过运算每个规划单元的不可替代性,共选定保护优先区9个,包括121个县(市、民族自治县)。建议以9个保护热点区为基础,率先建立各区域内保护网络,同时在已建保护区日常巡护中加入两栖爬行动物巡护内容。