Quality of Water Wells in an Agricultural Area in the City of La Plata,Argentina

The quality of the water from 62 home wells in a section (with no sewerage system) of the agricultural-industrial area of La Plata, was analyzed. The measurement of the studied parameters concentrations were compared with those obtained in seventeen water wells located in another area of town, with commercial characteristics. The pH, total dissolved salts (TDS), nitrates, chlorides, total hardness (TH) and coliform bacteria, these being differentiated between colifaecals and IAC group bacteria, were studied. The average concentration of TDS was 619 and 497 mg L^-1 respectively. 34% of the samples exceeded the limit of 45 mg L^-1 established by the World Health Organization (WHO). The nitrate levels varied widely from 6 to 216 mg L^-1, with an average value of 56 mg L^-1 in the agricultural area, and between 5 and 61 mg L^-1 in the commercial area, with an average of 19 mg L-1. The average concentrations of chlorides and TH were 89 mg L^-1 and 177 mg L^-1, respectively in the agricultural area; while in the other area, the average levels were 38 mg L^-1 chloride and 107 mg L^-1 TH. Significant differences were observed between the chemical parameters evaluated in the two areas analyzed. E. Coli bacterium was detected in 49% of the well water samples analyzed. IAC group bacteria were confirmed in 28% of the samples. The average depth of the water wells within 10 m from the cesspits was 28.2 m, and those situated farther than 10 m. had an average of 39.9 m depth. Results indicated a remarkable quality degradation of the well waters as regards their contents of E. Coli bacteria and nitrate. This could be due to the deficient construction of the absorption wells, to their closeness with cesspits and the inexistence of septic chambers within every dwelling.     

Rehabilitation of desurfaced soils by afforestation in La Plata County,Argentina

Removal of topsoil, mainly for making bricks, is one of the main causes of soil loss around large urban centres of the Humid Pampa, Argentina. In about 7 per cent of La Plata County, the 20–40 cm thick A‐horizon has been removed for that purpose. Most of the affected areas were originally prime farmland; however, with removal of the A‐horizon they became unsuitable for agriculture, including grazing, since the exposed Bt‐horizon is unsuited for plant growth due to its high clay content (45–65 per cent) and the low nutrient levels. Since trees survive better on poor soils than do agricultural crops, the possibility of afforestating desurfaced soils has been studied. Eucalyptus are one of the major species used in tree planting programmes aimed at reclaiming degraded soils since they are fast growing and can grow to commercial size in a wide range of soils and climatic conditions. The work reported here was done in a desurfaced Vertic Argiudoll and a similar non‐desurfaced soil (control). Three Eucalyptus species were tested, i.e. E. camaldulensis, E. viminalis and E. dunnii. Their height and diameter (dbh) growth were 47.9 to 75.8 per cent less and timber volume 86.5 to 98.5 per cent less on the desurfaced soil. E. camaldulensis grew best in all the parameters in the desurfaced soil. Although tree growth was poor, afforestation may be an alternative use for desurfaced soils where agriculture and livestock breeding are not possible. Copyright © 2002 John Wiley & Sons, Ltd.     

Content and distribution of lithium in La Pampa soils (Argentina)

Abstract

Extractable li with ammonium acetate was determined by flamephotometry, in normal soils, alkaline soils and saline soils in the Province of La Pampa (Argentina).

The soils were originated from differents parent material, with various rainfalls (arid to subhumid climate) and management.

The higher contents were found in saline soils. In the other soils the extractable lithium content depends on the parent material, but not on rainfall.

Different patterns of vertical and horizontal distribution of extractable lithium were found.

The origin of extractable lithium is here discussed.     

Sediment Pollution, Transport, and Abatement Measures in the City Canals of Delft, the Netherlands

This paper presents an overview of a long-term study on sediment pollution in the city canals of Delft, the Netherlands. This pollution was most evident for the inner city canal system, with copper, lead, zinc, and polycyclic aromatic hydrocarbons (PAHs) as main pollutants. Sediments of the outer city canals generally had a much better quality. Pollution levels, mutual correlations, and spatial variations were investigated for the various sediment parameters. Also, heavy metal binding forms onto Delft sediments were assessed with the help of sequential extraction techniques; results were found to be in line with expected preferential physicochemical binding processes. Input of sediments into the Delft inner city canals was shown to be largely driven by busy shipping traffic on the main canal surrounding the inner city. Mass balances for the inner city were used to quantify internal and external pollution sources; 65?C85?% of the heavy metal pollution can be attributed to sources outside the Delft area. As shown by factor and cluster analyses, it is highly probable that these external sources derive from the river Rhine. A gradual improvement of the sediment quality has set in; it is expected that, due to further pollution abatement measures, this improvement will continue over the years to come. With respect to the ship-induced sediment input into the inner city canals, it was estimated that a reduction of ship velocities to <1.5?m/s will bring down the sediment input mentioned above to about 85?%.     

Impact of Air Pollutant Emissions on the Ecosystems in the Vicinity of Industrial Areas of Indian Sub-Tropics

An investigation was conducted near the industrial areas of West Bengal, Indian subtropics to study the effect of emissions through various factories and thermal power plants on the quality of water in lakes, tanks, ponds, even well waters in relation to its use in the welfare of the society (agricultural use, psciculture and other domestic uses). The results showed that intensity of acidity (water pH) as well as concentration of various soluble salts and BOD and COD in the vicinity of an industrial area (i.e. within 100 metres) were very low. A substantially higher acidity and ion concentration were recorded up to 1 km away from industry, where the growth of aquatic plants, organisms and the production of fish (in lakes and tanks) were severely affected. The results further indicated that the acidity of water gradually increases up to pH 5.4 and concentration of sulphates and chlorides (880 and 570 mg 1^?1 respectively) between 1–2 km from the industriy, suggesting that aquatic ecosystems and domestic, agricultural and fish production are less affected with increasing distance from industry.     

Effects of Water Network Synthesis on the Air Pollutant Emissions and Energy Consumption of a Whole Economy

Environmental and energy performances of a water network system (WNS) utilizing water reuse are compared to those of a conventional water system (CWS) supplying only freshwater from the perspective of an entire economy and life cycle. Environmental input–output analysis (EIOA) is used to evaluate their air pollutant emissions and energy consumptions. The global warming potential and the emissions of carbon monoxide and of volatile organic compounds from the WNS are less than those from the CWS because of the decrease in the consumption of industrial water, while the emissions of sulfur dioxide and of nitrogen oxides and energy consumption from the WNS are greater because of the increase in electricity consumption for pumping. For perfectly environmentally-friendly water reuse, electricity consumption should be constrained or optimized in water network synthesis, and primary energy mix for electricity generation should be shifted towards renewable energy.     

Air Pollution and its Impact on Lung Function of Children in Delhi, the Capital City of India

Air pollution is a major contributor to several respiratory problems, it affects the whole population in general but children are more susceptible. Exposure to automobile exhaust is associated with increased respiratory symptoms and may impair lung function in children. In view of this, the study was conducted among the children of Delhi, the capital city of India, where ambient air quality was much above the National Ambient Air Quality Standards. The study was conducted in children aged 9–17 years. Pulmonary function test was carried out following the guideline of American Thoracic Society using a portable, electronic spirometer. Air quality data was collected from Central and State Pollution Control Boards. In addition, the level of particulate matter in indoor air was measured by portable laser photometer. Lung function was reduced in 43.5% schoolchildren of the urban area compared with 25.7% of control group. The urban children had increased prevalence of restrictive, obstructive, as well as combined type of lung functions deficits. Besides higher prevalence, the magnitude of lung function deficits was also much more in them. After controlling potential confounders like season, socioeconomic conditions and ETS, PM10 level in ambient air was found to be associated with restrictive (OR?=?1.35, 95% CI 1.07–1.58), obstructive (OR?=?1.45, 95% CI 1.16–1.82), and combined type of lung function deficits (OR?=?1.74, 95% CI 1.37–2.71) in children. Spearman's rank correlation test reaffirmed the association. The study confirms that the level of air pollution is affecting the children.     

基于能值分析的周口市农用地可持续利用研究

以河南省周口市为例,选取2000—2009年统计数据,利用能值分析法对周口市农用地的可持续利用性进行了研究。结果表明:(1)农业投入主要以购买资源投入为主,其所占总能值投入比重达到90%以上,且工业能投入很大程度上依赖于化肥、农药的投入,降水量显著影响可更新环境资源的投入;(2)农业产出以种植业和畜牧业为主,所占比例达到99%左右,渔业和林业所占比重过低,农业产出结构比较单一;(3)农用地的使用在经济可持续性方面取得了初步成效,但在生态可持续性和社会可持续性方面却处于较低水平,可持续利用指数显示农业系统具有很大的活力和较大的发展潜力;不可持续性表现在化肥和农药的大量投入以及单一的农业产出结构。     

Dry and Wet Deposition of Nitrogen Emitted in Buenos Aires City to Waters of de la Plata River

Dry and wet deposition of atmospheric nitrogen species (NO₂ and HNO₃) coming from nitrogen oxides emissions in Buenos Aires city to surface waters of de la Plata River were estimated. Atmospheric dispersion models DAUMOD-RD (v.2) and CALPUFF were applied to area and point sources, respectively. These models were run considering 1 year of hourly meteorological data. Emission information included a typical diurnal variation of area source emissions. Annual atmospheric nitrogen (N–NO₂?+?N–HNO₃) deposition to 1,763 km² of the river was 35,600 kg-N year^?1. Dry deposition processes accounted for 89% of this value. The small contribution of wet deposition was a consequence of the very few cases (5%) of rain events during offshore wind conditions. Monthly dry deposition to 1,763 km² of the river varied from 1,628 kg-N month^?1 in February to 3,799 kg-N month^?1 in December, following the monthly occurrence of offshore winds. Monthly wet deposition varied from 1 kg-N month^?1 in June to 1,162 kg-N month^?1 in February. These results came from the combination of favorable conditions for formation of HNO₃ and the occurrence of precipitation during offshore wind situations. Spatial distribution of annual atmospheric N deposition showed a strong coastal gradient. Deposition values reached a maximum of 137.1 kg-N km^?2 year^?1 near the shoreline, which was reduced to the half at 4 km from the coast.     

Measurement of Volatile Organic Compounds in Urban Air of La Coruña,Spain

Twenty-eight volatile organic compounds have been measured in a 3-month monitoring campaign. The sampling point is locatedin the urban centre of La Coruña, a medium-size town in theNorthwest of Spain. Only a petrol refinery can be consideredas an important point VOCs source in its surrounding area.The municipal landfill collapsed in September 1996, and rebuilding works caused strong odour episodes at the urbancentre. We tried to check how this problem affected urban airquality. Samples were taken with Tenax-TA tubes and analysedby thermal desorption-GC-MS. From the results obtained, traffic emissions were recognised as the main VOCs source inthe sampling zone. On November 9th a contaminationepisode took place. Aromatic and aliphatic compounds levelswere probably affected by emissions from fuel treatmentprocesses in a nearby petrol refinery. No influence onquantified VOCs concentrations from the remaking landfillworks was observed. Several compounds (organosulphurs, estersand alcohols) were recognised as the cause of odour problems.     

基于能值分析的德州市农业生态系统分析

在综和分析可持续发展学科动态与相关生态学理论最新进展的基础上,运用能值分析方法,对德州市农业生态系统1998-2007年的能值变化及其可持续性动态进行了分析.结果表明,德州市农业生态系统总能值用量呈增加趋势,农业生态系统维持对不可更新资源的依赖性逐渐增强,环境负荷率呈逐渐增加趋势,可持续性发展压力较大.未来农业生态系统管理要大力发展节水灌溉农业;应积极引进技术,增加劳动力的智力资源能值投入,调整工业辅助能投入,提高能值受益率;并探索建立多层次、高功能的生态农业模式.     

珠海城区暴雨径流污染负荷估算及其评价

基于对广东珠海城区暴雨径流污染的监测,引用SCS模型对城区暴雨径流污染负荷进行估算并分析评价。结果表明,珠海城区暴雨产流年平均1529.2mm,其中以交通主干道和商业区径流量最大。暴雨径流污染物浓度水平较高,T—N,T—P,COD_(Cr)和BOD_5负荷总量分别为765.27,74.06,11 958.94和1104.71t,其中COD_(Cr)负荷为工业点源污染的72.32％,占珠海非点源污染总负荷的24.69％。暴雨径流在雨后短时间内会使受纳水体的水质迅速恶化。因此,珠海城区暴雨径流对水环境的威胁较大。     

Acidic Precipitation and Large-Scale Transport of Air Pollutants Observed in Korea

Acid rain at a rural site in Chongwon (KHN), central Korea has been under observation since 1990. To substantiate the 10-year observations, rain samples from six other sites were also collected and analyzed. Results show that acid rain occurred frequently at all sites. At KHN, seasonal and annual variability of pH values had a 10-year VWM value of 4.67 and an arithmetic mean value of 5.09. In general, a high value of pH occurred during springtime when the occurrence of yellow sand (dust) was prevalent in East Asia; during summer, heavy rain usually contained neutral pH values. During other seasons, the degree of acidic precipitation usually coincided with certain air flows. Most frequently, air flows and cyclones coming from south and central China often resulted in precipitation with low pH values observed in Korea. Using daily satellite observations from 1996, we have also been monitoring the long-range and large-scale transport of air pollutants (LSTAP) over East Asia. Many samples of LSTAP were obtained when they were crossing the Yellow Sea and moving over the Korean Peninsula and to SW Japan. The width of the Yellow Sea is ca. 350～700 km and air pollutants take 1～2 days to cross it. Cases of acid rain in Korea clearly correlate wth the LSTAP from source regions in China.     

Design,Evaluation and Application of a Continuously Stirred Tank Reactor System for Use in Nitric Acid Air Pollutant Studies

Nitric acid (HNO₃) vapor is a significant component of air pollution. Dry deposition of HNO₃ is thought to be a major contributor to terrestrial loading of anthropogenically-derived nitrogen (N), but many questions remain regarding the physico-chemical process of deposition and the biological responses to accumulation of dry-deposited HNO₃ on surfaces. To examine these processes experimentally, a continuously stirred tank reactor (CSTR) fumigation system has been constructed. This system enables simultaneous fumigation at several concentrations in working volumes 1.3 m dia by 1.3 m ht, allowing for simultaneous fumigation of many experimental units. Evaluation of the system indicates that it is appropriate for long-term exposures of several months duration and capable of mimicking patterns of diurnal atmospheric HNO₃ concentrations representative of areas with different levels of pollution.     

基于灰色关联分析法的白城市洪水资源利用效益分析

[目的]对吉林省白城市洪水资源利用效益进行分析,为该地区洪水资源的合理配置提供科学依据。[方法]采用灰色关联分析法,对2008—2017年白城市洪水资源利用效益衡量及其所依赖的经济收益、生态环境改善、社会发展等变化,分别从直接经济效益、生态环境效益和间接经济社会效益3个角度中确定指标参数和指标体系进行关联分析。[结果]洪水资源利用对各效益指标的影响关联度均在0.55以上,目前洪水资源对生态环境效益影响最为明显,占全部效益的43%。[结论]灰色关联分析法为有效利用和管理洪水资源提供了新的思路与评价方法,白城市洪水资源更多以自然形式为环境及生态所利用,所带来的效益更多在生态资源本身,当地洪水资源具有很大的开发潜力。     

基于RUSLE模型的梅河口市土壤侵蚀动态分析

[目的]定量分析区域土壤侵蚀强度动态变化及其影响因素,为区域水土保持工作提供科学依据。[方法]基于3S技术,采用RUSLE模型计算吉林省梅河口市2010年和2017年的土壤侵蚀模数,并从土地利用类型、坡度和水土保持措施3个方面分析土壤侵蚀变化特征。[结果](1)梅河口市2010年、2017年的平均土壤侵蚀模数分别为698.75,678.25t/(km~2·a),土壤侵蚀状况有所改善。(2)梅河口市的土壤侵蚀与坡度和土地利用有关,95%的土壤侵蚀分布在坡度15°坡地,土地利用以耕地和林地为主的区域。(3)2010—2017年,水保项目实施区域的平均土壤侵蚀模数下降了154.08t/(km~2·a),土壤侵蚀量减少了2.65×10~4 t。[结论]水保项目的实施在改善水土保持功能上取得较大的成效,但治理后的区域仍存在一定强度的侵蚀,且土地利用的不利转变加重了区域土壤侵蚀。因此,区域水土流失治理工作需考虑多部门协同,从源头上遏制发生水土流失的不利因素。     

基于生态足迹和物质流的可持续性分析与评价——以石家庄市为例

以生态足迹模型和物质流分析为核心工具,对2002—2011年石家庄市的生态足迹和物质流代谢进行了分析与可持续性评价。结果表明:（1）研究时段内石家庄市人均生态足迹总体上呈上升趋势,2011年达到6.964 207 hm²/人,人均生态承载力由0.251 515 hm²/人下降到0.213 777 hm²/人,此期间内历年均为生态赤字,至2011年人均生态赤字已高达6.750 43 hm²/人。表明石家庄市对自然资源的利用超出了生态承载力的范围,生态发展处于不可持续状态。（2）石家庄市直接物质输入总体呈增长趋势,由2002年的57 695.72万t增加到2011年的75 434.04万t,区域资源开采活动不断增强,具有资源依赖性,资源开发比较粗放,区域内隐藏流（DHF）成为环境压力的主要来源。（3）与2002年相比,2011年物质生产力（MP）增加了1.78倍,数据显示其在物质利用效益方面有了改善,但资源利用效率仍较低。     

Using Seven Types of GM (1, 1) Model to Forecast Hourly Particulate Matter Concentration in Banciao City of Taiwan

In this study, seven types of first-order and one-variable grey differential equation model (abbreviated as GM (1, 1) model) were used to predict hourly particulate matter (PM) including PM₁₀ and PM_2.5 concentrations in Banciao City of Taiwan. Their prediction performance was also compared. The results indicated that the minimum mean absolute percentage error (MAPE), mean squared error (MSE), root mean squared error (RMSE), and maximum correlation coefficient (R) was 14.10%, 25.62, 5.06, and 0.96, respectively, when predicting PM₁₀. When predicting PM_2.5, the minimum MAPE, MSE, RMSE, and maximum R value of 15.24%, 11.57, 3.40, and 0.93, respectively, could be achieved. All statistical values revealed that the predicting performance of GM (1, 1, x ⁽⁰⁾), GM (1, 1, a), and GM (1, 1, b) outperformed other GM (1, 1) models. According to the results, it revealed that GM (1, 1) GM (1, 1) was an efficiently early warning tool for providing PM information to the inhabitants.     

基于灰色模型的长沙市生态足迹与生态承载力预测分析

生态足迹方法是分析区域可持续发展状况的重要方法。基于生态足迹模型对长沙市1996—2008年的生态足迹进行计算,并利用灰色模型对其发展趋势进行了预测分析。结果表明:在1996—2008年,长沙市人均生态足迹由1.232 6 hm²增加到1.872 2 hm²;同期人均可利用生态承载力由0.391 8 hm²逐年下降到0.355 0 hm²,人均生态赤字由1996年的0.840 8 hm²增加到2008年的1.517 2 hm²,呈增长趋势。同时根据预测出的研究区域2011—2020年的人均生态足迹和人均可利用生态承载力,得到2020年研究区域人均生态赤字将增加到2.736 3 hm²,表明当前长沙市处于一种不可持续的发展状态,区域超负荷的生态状态呼吁当地政府部门积极采取有效措施,发展生态经济,建设生态文明,以真正实现资源环境与区域经济的协调发展。     

基于脱钩理论的烟台市碳排放效应分析

[目的]通过分析烟台市2000—2011年碳排放与经济发展之间的关系,为烟台市碳减排及发展低碳经济提供参考。[方法]基于土地利用碳源/碳汇研究的理论框架和计算模型,首先对烟台市土地利用、能源消费等数据进行分析,计算了不同土地利用类型的碳源/汇。然后利用Tapio脱钩模型分析该区碳排放与经济发展之间的脱钩弹性关系。[结果](1)建设用地是主要碳源,其面积与净碳排放量成倒U型库兹涅茨曲线关系。(2)林地为主要碳汇,其他用地影响较小且主要表现为碳汇。(3)烟台市净碳排放量在2001—2011年持续增长,年均增长率不断降低。[结论]烟台市碳减排工作已取得一定的成效,但减排形势依然严峻。其经济发展3个阶段(连接阶段、脱钩阶段Ⅰ和脱钩阶段Ⅱ)分别对应于其碳排放的高速增长、较快增长、稳定阶段这3阶段。