Water resource management in Kabul river basin, eastern Afghanistan

Severe drinking water shortage affects all resident of the Kabul river basin. Two and a half decades of civil war in Afghanistan (it began in late 1978) have resulted in widespread environmental degradation and water resource development throughout the country. The war has already finished and, therefore, water resource management for supplying water is one of the most important tasks for Afghanistan’s government. The Kabul river basin which is the most populated area in the country is located in the eastern part of Afghanistan. This article deals with the water resource properties of the Kabul river basin and also water demand in the important cities of the basin, such as Kabul, the capital and the largest city in the country. Also a few suggestions for providing water for domestic and agriculture purposes in short term, medium time and long term have been discussed.     

Determination of 2,4- and 2,6-dinitrotoluene biodegradation limits

This study was carried out to explore the lowest achievable dinitrotoluene (DNT) isomer concentrations that would support sustained growth of DNT degrading microorganisms under an aerobic condition. Studies were conducted using suspended (chemostat) and attached growth (column) systems. The biodegradation limits for 2,4-dinitrotoluene chemostat and column system were 0.054 ± 0.005 and 0.057 ± 0.008 μM, respectively, and for 2,6-dinitrotoluene, the limits for chemostat and column system were 0.039 ± 0.005 and 0.026 ± 0.013 μM, respectively. The biodegradation limits determined in this study are much lower than the regulatory requirements, inferring that bacterial ability to metabolize DNT does not preclude applications of bioremediation (including natural attenuation) for DNT contaminated media.     

Contamination by arsenic and other trace elements of tube-well water along the Mekong River in Lao PDR

Arsenic and other trace element concentrations were determined for tube-well water collected in the Lao PDR provinces of Attapeu, Bolikhamxai, Champasak, Savannakhet, Saravane, and Vientiane. Water samples, especially from floodplain areas of central and southern Laos, were significantly contaminated not only with As, but with B, Ba, Mn, U, and Fe as well. Total As concentrations ranged from <0.5 μg L⁻¹ to 278 μg L⁻¹, with over half exceeding the WHO guideline of 10 μg L⁻¹. 46% of samples, notably, were dominated by As(III). Samples from Vientiane, further north, were all acceptable except on pH, which was below drinking water limits. A principal component analysis found associations between general water characteristics, As, and other trace elements. Causes of elevated As concentrations in Lao tube wells were considered similar to those in other Mekong River countries, particularly Cambodia and Vietnam, where young alluvial aquifers give rise to reducing conditions.     

某糠醛厂排放废水及周围地下水的GC/MS测定

某地地下水显淡黄色有异味，为查明被污染原因，我们利用ＧＤＸ－１０２树脂富集，对该处唯一的一家工厂——某糠醛厂排放的废水及其周围地下水同时进行了ＧＣ／ＭＳ测定．以上两种水体中均有呋喃类化合物（包括糠醛）及酚类化合物检出，而远离工厂的上游地下水未发现以上两类化合物，这一结果表明，该地下水区被工厂排放的废水所污染     

Climate change impacts on groundwater resources in Mekong Delta under representative concentration pathways (RCPs) scenarios

Groundwater is the essential resource for various uses and have a great economic importance especially in the areas like Mekong Delta, which is the home for some 18 million people and produces a half of Vietnam’s rice and contributes substantial part of the country’s gross domestic product (GDP). Sustainable use of the groundwater resource is threatened by its uncontrolled abstraction and climate change. This study assesses groundwater resources in Mekong Delta aquifer system in the context of climate change. A set of models are used for the purpose. Groundwater recharge and its spatial variation are estimated using WETSPASS model, groundwater level and storage are estimated using MODFLOW and future climatic conditions in the area are developed by downscaling the data of five General Circulation Models (GCMs) retrieved from CMIP5 data portal. Two representative concentration pathways (RCPs) scenarios (RCP4.5 and RCP8.5) are considered for projecting future conditions of groundwater resources. Results reveal that the future average annual temperature is projected to increase by 1.5 °C and 4.9 °C by the end of the 21st century under RCP4.5 and RCP8.5 scenarios, respectively. Future rainfall is projected to increase in wet season and decrease in dry season. Groundwater recharge is projected to decline in short-, medium-, and long-terms. As a result, groundwater levels and storage are also projected to decline in future. These findings may help decision-makers and stakeholders for devising sustainable groundwater management strategies in Mekong Delta.     

Groundwater conditions under a reconstructed prairie chronosequence

Chronosequences are useful to evaluate long-term changes in ecosystem services but assessing groundwater quality changes using this approach has rarely been done. In this study, groundwater level and quality comparisons were made in a watershed-scale reconstructed prairie chronosequence that extended back in time approximately 13 years at the Neal Smith National Wildlife Refuge (NSNWR) near Prairie City, Iowa. Our objectives were to determine whether groundwater conditions varied significantly across the chronosequence and quantify the rate of nitrate concentration reduction when row crop fields are replaced by prairie. We installed 19 groundwater wells at upland locations selected to provide similar soil type, landscape position and slope. Water samples were collected on five occasions in 2006 and 2007 and analyzed for field parameters, anions and NO₃-N, NH₄-N and PO₄-P. Significant groundwater changes were primarily associated with groundwater levels, and groundwater nitrate and chloride concentrations. The groundwater was deeper under the older prairie plantings but fluctuated similarly among all well sites. Groundwater nitrate and chloride concentrations decreased 0.58 and 0.52 mg/l per year over the 13-year chronosequence, respectively. Results are seen to provide some guidance to land managers regarding possible nitrate concentration reductions achievable from converting cropland to perennial land cover in similar geomorphic settings.     

地表水和地下水中的砷、硒同时测定

通过利用双道原子荧光法,同时对地表水和地下水样品中砷、硒进行测定,具有操作更加简单、监测分析速度快、节省试剂等优点。     

葫芦岛市钢屯地区地下水钼污染状况调查

葫芦岛市是中国最重要的钼矿基地。而钼矿主要集中在葫芦岛市连山区钢屯镇。随着钼的大量开采和冶炼,导致大量生产废水外排和偷排,造成附近地区地下水污染,为了弄清该地区污染,为环境管理提供决策依据,我们对该地区的地下水中的钼进行了监测。     

地下水污染健康风险评价理论体系研究

基于对风险的认识,以地下水为研究载体提出地下水污染健康风险评价的概念.按照风险识别、风险量化、风险管理的步骤构建了地下水污染健康风险评价的理论体系,并对每个步骤进行了详细的描述和研究方法的探讨,提出了判定的原则和方法以及对我国地下水污染健康风险管理的建议,以期为我国地下水资源管理和保护工作提供科学依据.     

“The commons” as a dynamic variable in understanding strategic alliances of scale: A groundwater case study in Pajaro Valley,California

Groundwater, a critical resource in many parts of the world, is often characterized as a common pool resource (Brozovic et al., 2006). Multiple individuals utilize groundwater from a basin, and each person has the capacity to reduce the quantity or quality available to others. We turn to a case study of the Pajaro Groundwater Basin in Central California to re-envision the characterization of “commons.” While providing a useful frame from which to analyze groundwater depletion in the Pajaro, we find Common Pool Resource (CPR) theory to be imprecise in its approach to a geographic scale. The notion of the “commons” is central to CPR studies, but there is wide divergence in what the “commons” constitutes, both spatially and socially (Laerhoven and Ostrom, 2007). Rather than propose a normative definition for the “commons,” we suggest that the “commons” as a geographic category is socially constructed and dynamically active over time, akin to the analytic of scale as developed within the fields of political ecology and geography. This move from situating the “commons” as a fixed and discrete geographic area to that which is constantly changing and relational helps us to better understand the ways in which water users collaborate and communicate around shared groundwater sources.