黄河三角洲人工草场群落土壤盐分动态集成预报模型及其应用

提出了以ＧＭ（１,１）模型拟合发展的趋势、傅里叶变换撮周期分量ＡＲ（ｐ）模型模拟随机过程的集成预报模型,并用于黄河三角洲人工草场群落土壤盐分的定量研究中,经理论和应用检验证明：该模型能以较高的精度模拟或预报土壤盐分在较长时期内的动态变化过程,方法简单,计算工作量小,并优于传统的单一预报模型。     

塔里木河干流农田排水资源化研究

近几十年分析资料对比表明 ,农田排水对塔里木河干流水质盐化的影响不断加重。在塔里木河干流 ,农田排水资源化利用有如下几个有利条件 :( 1)农田排水有一定数量且渠网的延伸和改造难度不大 ;( 2 )荒漠可作为农田排水资源化利用的场所 ;( 3)农田排水仍可勉强适于耐盐植物生长。根据区域不同 ,利用农田排水拓展乔灌草防沙带、增加盐成土荒漠耐盐植被的盖度、使人工绿洲边缘的荒漠能够生长耐盐植物等都是农田排水资源化利用发展的方向     

长江沿江区域空间结构系统调控研究

长江沿江区域“点－轴－集聚区”空间结构等级系统主要由三级点型式、三级轴型式和三个集聚区组成,形成机制在于其开发条件,中心一边缘疚以及区位和政策因素等,相应的调控措施主要包括：（１）正确处理沿江轴线和三级轴线（省域主要轴线）之间的关系,扩大参与沿江开发开放的地域范围,构筑与沿江轴线相交的新一三级轴线,重点发展一、二级轴线的节点港口城市;（２）加快沿江综合交通运输网建设,特别是沿江铁路建设;（３）优化     

陇南长江流域经济发展和生态重建战略研究

陇南长江流域大多地处嘉陵江上游的源头地区,是一个资源较为富集但经济相对落后、生态环境脆弱且人口压力较大的丘陵山区。本文从可持续发展的角度出发,着眼世纪之交摆脱贫困与奔向小康转换时期经济发展和生态重建的协调演进,提出产业结构调整的基本思路是立足山区优势发展特色农业,市场配置资源、培植支柱工业,商贸、旅游并举、突出第三产业、强化基础设计、增强发展后劲;空间结构重组的战略构想是重点发展东部经８济重心区、     

长江中游地区防洪与农业现代化

１９９８年长江大洪水后开始实施的“平垸行洪,退田还尖”的土地利用调整方案,从长远来说应录求农业安且且收入逐渐提高条件下的土地利用,长江中游地区应积极推进农业现代化,提高农业劳动生产率,转移,减水分蓄洪区的人口,移民建镇,对区内的土地要促进其规模经或,由优秀的有文化的农民经营,平时只有少量的直接从事农业生产的经营管理人员,农忙时则大量地作用委节性合同工或实现机械化;大洪水时退田还湖,减轻长江干流大洪     

基于数字流域的水文过程模拟研究

考虑流域下垫面空间变异性,基于数字高程模型构建了数字流域,并在此基础上对描述流域水文物理过程的数学方法进行了探讨,文章认为,数字水文模型是一种有物理基础的包含大容量信息的现代模拟灌河实例研究表明,数字水文模型可以十分方便地输出水文要素和状态变量的空间分布与时间序列,这对充分利用现有观测信息进行水文信息的深层挖掘创新了条件。     

干旱地区水污染控制系统初探

应用数学规划方法,科学地组织污染物的排放或科学地协调各个治理环节,以乌鲁木齐市水磨河流域水污染控制系统为例,对干旱地区水污染控制系统进行了初步探索,从而得出干旱地区污水处理费用的合理负担,并得出污染物排放的数量,质量受自然地理条件制约的结论。     

Levels of perfluorochemicals in water samples from Catalonia,Spain: is drinking water a significant contribution to human exposure?

Background, aim, and scope  In recent years, due to a high persistence, biomagnification in food webs, presence in remote regions, and potential toxicity, perfluorochemicals (PFCs) have generated a considerable interest. The present study was aimed to determine the levels of perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and other PFCs in drinking water (tap and bottled) and river water samples from Tarragona Province (Catalonia, Spain). Materials and methods  Municipal drinking (tap) water samples were collected from the four most populated towns in the Tarragona Province, whereas samples of bottled waters were purchased from supermarkets. River water samples were collected from the Ebro (two samples), Cortiella, and Francolí Rivers. After pretreatment, PFC analyses were performed by HPLC-MS. Quantification was done using the internal standard method, with recoveries between 68% and 118%. Results  In tap water, PFOS and PFOA levels ranged between 0.39 and 0.87 ng/L (0.78 and 1.74 pmol/L) and between 0.32 and 6.28 ng/L (0.77 and 15.2 pmol/L), respectively. PFHpA, PFHxS, and PFNA were also other detected PFCs. PFC levels were notably lower in bottled water, where PFOS could not be detected in any sample. Moreover, PFHpA, PFHxS, PFOA, PFNA, PFOS, PFOSA, and PFDA could be detected in the river water samples. PFOS and PFOA concentrations were between <0.24 and 5.88 ng/L (<0.48 and 11.8 pmol/L) and between <0.22 and 24.9 ng/L (<0.53 and 60.1 pmol/L), respectively. Discussion  Assuming a human water consumption of 2 L per day, the daily intake of PFOS and PFOA by the population of the area under evaluation was calculated (0.78–1.74 and 12.6 ng, respectively). It was found that drinking water might be a source of exposure to PFCs as important as the dietary intake of these pollutants. Conclusions  The contribution of drinking water (tap and bottled) to the human daily intake of various PFCs has been compared for the first time with data from dietary intake of these PFCs. It was noted that in certain cases, drinking water can be a source of exposure to PFCs as important as the dietary intake of these pollutants although the current concentrations were similar or lower than those reported in the literature for surface water samples from a number of regions and countries. Recommendations and perspectives  Further studies should be carried out in order to increase the knowledge of the role of drinking water in human exposure to PFCs.     

闽江流域畜禽粪便的污染负荷及其环境风险评价

从闽江流域畜禽养殖业现状分析入手,根据作物所需畜禽粪尿肥的最大量,估算流域各县市的畜禽污染物产生量和农田畜禽粪便负荷量,对各县市畜禽养殖粪便污染进行潜在的环境风险评价.结果表明:闽江流域大多数集约化养殖场集中分布于中上游,并有向下游扩散的趋势;流域农田畜禽粪便负荷量平均达22.95 t·hm-2·a-1;整个流域的畜禽污染已对环境产生风险,尤其是富屯溪、沙溪流域更为突出.     

长江上游重庆段近20 a降水时空变化特征

全球气候变暖背景下,中国的降水分布日趋复杂,气象灾害造成的损失巨大。为满足防灾减灾与水资源管理的数据支撑需求,基于长江上游重庆段近20 a降水数据,利用线性回归、M-K非参数检验等方法,探究降水的时间变化趋势与空间分异特征。结果表明：近20 a重庆市年降水量在875.6—1348.2 mm。时间上,春、秋两季呈明显增多的趋势,其中3月最显著。降水在14 a时间尺度的周期过程线中波动最强,是第一主周期。空间分布上,呈西低东高的特点,在渝西和长江河谷地区降水相对偏少,主要受重庆地形的影响;渝西和渝东北地区秋季降水显著增多。研究结果可为长江流域旱涝灾害防治、水资源开发利用及经济社会可持续发展提供数据支撑,同时可为植被修复与生态廊道保障提供参考。