发展芦苇湿地污水处理绿色生态工程初论

1问题的提出新疆地处中温带（温带与暖温带）欧亚大陆腹部极端干旱的荒漠地带。四周高山环绕，远离海洋，自然地理环境封闭，是形成新疆干旱自然生态环境的地理基础。其典型的温带大陆性气候决定了新疆气候干燥、少雨、多大风、日较差和年较差大的特征，且冬季寒冷漫长、夏季炎热短促，全年平均降水量为145mm，降水量稀少，只有全国平均降水量630rum的23％，而蒸发量约为2000mrn－2500mm，干燥度在4一伤之间。根据干旱指数分区指标，全区除北疆、天山山区、阿勒泰山区和塔城北部山区干旱指数在5以下属于干旱、半干旱地区外，其余地区干旱指…     

海南西部资源环境一体化研究

传统发展模式引发的资源环境问题迫使人类思考去寻求新的可持续的发展模式,资源环境一体化就是适应此背景的新兴发展理念。以海南西部沙地环境资源化与山区资源环境化的发展实践,实证分析了资源环境一体化的发展模式与发展机制。按资源与环境是可相互转化的这一资源环境一体化理论基础,海南西部干旱与多沙的环境可将其作为旅游资源进行开发,而针对山区资源过度利用的现状,则通过实施设立自然保护区、退耕还林、封山育林等措施实行保护性开发,实现山区资源环境化。重视环境与可持续发展思想、资源与环境的同源性与资源时效性、科学发展与技术进步、环境政策的完善与严格、政府与企业推进是促进资源环境一体化的主要推动机制。     

我国山区综合开发研究综述

我国山区拥有丰富的自然资源,山区的发展在我国国民经济发展中占据着十分重要的地位.归纳并阐述了山区开发的内涵,分析总结了国内外山区综合开发的历程与实践经验.在总结国内外诸多学者研究成果的基础上,结合目前我国山区综合开发的具体情况,提出了我国山区综合开发的几点建议.     

山区生态旅游开发初步研究——以粤西北旅游区为例

山区旅游资源丰富,生态系统复杂但旅游承载力弱,因此山区旅游开发具有区别于其它地区的特殊的发展模式,也使研究山区生态旅游的开发具有特别重要的现实意义。从生态旅游的概念、内涵以及山区生态旅游开发的主要模式分析出发,讨论了粤西北山区生态旅游发展的现状和问题,并以粤西北旅游区的核心区怀集县为重点,探讨了经济基础较薄弱的粤西北山区发展生态旅游的对策,给出了在开发与管理方面的具体建议。     

山区生态产业及其环境保育的作用研究

山区生态产业是依赖于山区丰富的自然资源按照生态学原理组织形成的生态与经济有机统一的产业发展形式。本文阐述了山区生态产业七个方面的特征：即山区生态产业对自然资源的特殊依赖性、受高度景观带的制约性、结构多样性与复杂性、建设长期性、经济收益级差性、开发水平落后性和开发任务艰巨性。在此基础上,文章从要素调控设计、垂直带幅生态调控设计、产业模式系统生态设计出发探讨了生态产业与垂直地带性的构建关系,并举例说明了山区生态产业开发建设对环境保护的积极作用。得出了山区生态产业的开发就是努力避免产业活动对生态环境干扰的逆向作用,积极引导与实现产业活动对生态环境干扰的正向作用的结论。     

柴达木盆地南缘宗家——巴隆地区环境地质问题初探

通过对柴达木盆地南缘宗家——巴隆地区环境地质现象的分析后认为：在不同的气候条件和地貌单元下产生了高寒山区以冻融作用为主、基层山区以重力作用为主、干旱盆地区以蒸发和风力作用为主的环境地质问题,这些环境地质问题具有水平分带性,掌握这一规律有助于我们更好地为经济建设服务     

联合开发荒山之初探

搞好小流域综合治理,加强水土保持,是贫困山区经济开发的基础性工作,也是山区人民脱贫致富奔小康的可靠途径。怎样进一步搞好水土治理和有效地开发贫困山区的资源呢?必须加大投资力度,在国家财政紧张的情况下,要多渠道、多层次的集资,采取股份制联合开发荒山,效益分成,以促进山区荒山的治理速度。青龙满族自治县的大石岭、谢庄的经验告诉我们:股份制联营开发治理荒山、荒坡是山区水土流失综合治理的可行途径,应大力推广。     

明末清初“湖寮田山”事件的环境反思

明末清初大埔山区所发生的“湖寮田山”事件,反映了当时人们在开发山区过程中所遇到的开发山林与环境保护间的矛盾问题。     

辽东山区微型小流域“特色农业”开发──以清源县大石沟村为例

本文立足于辽东山区微型小流域的地域空间,以经营开发“特色农业”为主线,着眼于山区小流域的特产资源的培育与开发。通过资源培育和对初级产品的深加工,将山区小流域的资源优势转化为产品优势和商品优势,从而实现山区流域经济运行的良性循环。     

柴达木盆地南缘宗农—巴隆地区环境地质问题初探

通过对柴达木盆南缘宗家－巴隆地区环境地质现象的分析后认为：在不同的气候条件和地貌单元下产生了高寒山区以冻融作用为主,基层山区以重力作用主,干旱盆地区以蒸发和几力作用为主的环境地质问题,这些环境地质问题具有水分带性,掌握这一规律有助于我们更好为经济建设服务。     

Soil moisture‐based drought monitoring at different time scales: a case study for the U.S. Great Plains

Short‐term agricultural drought and longer term hydrological drought have important ecological and socioeconomic impacts. Soil moisture monitoring networks have potential to assist in the quantification of drought conditions because soil moisture changes are mostly due to precipitation and evapotranspiration, the two dominant water balance components in most areas. In this study, the Palmer approach to calculating a drought index was combined with a soil water content‐based moisture anomaly calculation. A drought lag time parameter was introduced to quantify the time between the start of a moisture anomaly and the onset of drought. The methodology was applied to four shortgrass prairie sites along a North‐South transect in the U.S. Great Plains with an 18‐year soil moisture record. Short time lags led to high periodicity of the resulting drought index, appropriate for assessing short‐term drought conditions at the field scale (agricultural drought). Conversely, long time lags led to low periodicity of the drought index, being more indicative of long‐term drought conditions at the watershed or basin scale (hydrological drought). The influence of daily, weekly, and monthly time steps on the drought index was examined and found to be marginal. The drought index calculated with a short drought lag time showed evidence of being normally distributed. A longer data record is needed to assess the statistical distribution of the drought index for longer drought lag times.     

秋作的资源利用及效益分析

本文针对四川攀西地区冬干春旱的气候特点,分析了9种晚秋作物的产量、经济效益、生长发育动态及资源利用状况。结果表明,在8月底播种或移栽条件下,秋大麦、秋洋芋、秋豌豆、秋荞麦及秋菜的产量或效益较高。不同秋作可供不同地点或不同种植制度下选择。文章还对主要秋作的关键栽培技术进行了讨论。     

COPING WITH A SEVERE SUSTAINED DROUGHT ON THE COLORADO RWER: INTRODUCTION AND OVERVIEW1

ABSTRACT: In arid regions of rapid economic and population growth, adverse effects of droughts are likely to be increasingly serious. This article presents an introduction and overview of the papers collected in this special issue of the Water Resources Bulletin. The papers report on the second phase of a study of the impacts of and responses to a potential severe sustained drought in the Colorado River Basin in the southwestern U.S. The analyses were performed by a consortium of researchers from universities and the private sector located throughout the Basin. Tree ring studies suggest that droughts of duration and magnitude much more serious than any found in the modern records probably occurred in the Basin during earlier centuries. Taking the present-day configuration of the storage and diversion structures and the economic conditions in the Basin as the base-point, the general objectives of the study are three: first, to define a representative Severe Sustained Drought (SSD) and assess its hydrologic impacts; second, to forecast the economic, social and environmental impacts on the southwestern U.S.; and finally, to assess alternative institutional arrangements for coping with an SSD. The evaluation of impacts and policies was conducted with two distinct modeling approaches. One involved hydrologic-economic optimization modeling where water allocation institutions are decision variables. The second was a simulation-gaming approach which allowed “players” representing each basin state to interact in a real-time decision making mode in response to the unfolding drought.     

HYDROLOGICAL EFFECTS OF AN UNCONTROLLED FLOWING WELL,RED RIVER VALLEY,NORTH DAKOTA,USA1

ABSTRACT: In areas of the Red River Valley that overlie permeable Paleozoic sediments, wetlands and salinization have developed where unregulated flowing wells discharge brackish water. Field data were collected to assess the fate of water and salt from a well 25 km northwest of Grand Forks. Drilled during the drought of the 1930s, discharge was used to replenish water in a small oxbow pond used by livestock. The unregulated well discharges about 56 m³/day, measured since 1993. This discharge exceeds ground water flow from the site, thereby forming a ground water mound with a maximum height of 1 m and a diameter of about 300 m. Most soil and underlying sediments near the well have a hydraulic conductivity of 0.3 m³/day. Flow net analysis suggests that less than 25 percent infiltrates, with the remaining water lost to surface flow and evapotranspiration (ET). Evapotranspiration and slow infiltration has led to increased salinization, with shallow soils exhibiting EC to 500 milliSiemens/m. The most pronounced soil salinization occurs along the margins of the oxbow pond and meander scars. Wetland vegetation with low diversity comprises three zones, with species associations similar to those of closed basin prairie potholes to the west.     

重庆市城区交通干道空气污染特征

于秋冬两季，利用法国生产的自动监测仪对重庆市城区7条交通主干道的近地面空气质量进行了监测。结果表明：在监测期间，各个监测点PM1o是首要污染物，并且秋季比冬季污染严重，7条道路的日平均浓度为0．419mg／m^3，最大浓度为0．687mg／m^3，最大超标率为3．58倍；而NO2和SO2在冬季比秋季污染严重，NO2最高浓度是0.126mg／m^3，平均浓度是0．089mg／m^3，S02最高浓度是0．333mg／m^3，平均浓度是0．216mg／m^3，表明交通干道空气污染严重。     

REGIONAL AND TEMPORAL PATTERNS OF TOTAL SOLUTES IN THE SASKATCHEWAN RWER BASIN1

ABSTRACT: In the Saskatchewan River Basin (365,000 km²), which drains the Canadian prairie from the Rocky Mountains east to Manitoba, concentrations of total solutes are usually within the range of 100 to 1000 mg/L. Total solutes levels in tributaries increase markedly from west to east across the basin, as mountain snowmelt and dilute surface runoff are replaced by ion-rich ground water and concentrated prairie runoff as the major influences on solute concentrations. In contrast, total solutes concentrations in main-stem rivers are nearly constant, ranging 200–300 mg/L, with only a small increase across the basin. Dilute mountain runoff dominates solute concentrations in main-stem rivers, despite the influx of increasingly ion-rich water from tributaries. The principal long-term trends in total solute concentrations across the basin, as revealed by linear and sine-curve regressions, were due to the construction of reservoirs, which depress the natural winter maximum in solute concentrations and disrupt the sinusoidal annual pattern, while sharply reducing seasonal variation. These regression methods did not show anticipated anthropogenic increases in salt load in the Red Deer or South Saskatchewan Rivers, but a trend of slowly increasing solutes concentrations (2 mg/L/yr) was detected for autumn flows in the lower Bow River. Municipal wastes from the City of Calgary or irrigation return flows are probably responsible for this increase.     

Conflict Between Establishment of Instream Flows and Other Water Uses on Western Streams1

ABSTRACT: Establishment of minimum stream flows on most streams in arid areas of the west will create serious water conflicts. Much economic activity is dependent upon a limited water supply. to attempt to reallocate water to maintain minimum flows will cause severe disruption to planned uses of water and to weak segments of the economy such as irrigated agriculture.     

Managing Drought Through Water Markets: Farmer Preferences in the Rio Grande Basin1

Abstract: Managing drought in agriculture has taken on growing importance as population growth and environmental concerns place increasing pressures on agricultural water use. One alternative for agricultural water resource management in areas of recurrent drought is allocation through market mechanisms. While past research has aimed to explain why farmers are reluctant to participate in already established water markets, this research seeks to identify the appropriate market mechanism given farmers’ preexisting attitudes toward water markets. Statistical analysis of survey data from 166 farmer interviews in the Rio Grande Basin indicate that farmers are significantly more likely to participate in short‐term water mechanisms, such as spot water markets and water banks than in permanent transfer mechanisms, particularly those that fully separate water rights from land. In sharp contrast to expectations, the choice of market mechanism did not differ significantly between farmers based on their a priori intention to buy, sell or both buy and sell in these markets. Choice of market mechanism also did not differ among farmer types although small, lifestyle or hobby farmers clearly preferred spot water markets to other types of short‐term mechanisms. Evaluating these attitudes a priori may help to design more suitable water market mechanisms for the basin.     

REGULATED RIVER MODELING FOR CLIMATE CHANGE IMPACT ASSESSMENT: THE MISSOURI RIVER1

ABSTRACT: The Great Plains of the United States, drained primanly by the Missouri River, are very sensitive to shifts in climate. The six main stem dams on the Missouri River control more than one‐half of the nearly 1.5 million square kilometer basin and can store three times the annual inflow from upstream. The dams are operated by the U.S. Army Corps of Engineers using a Master Manual that describes system priorities and benefits. The complex operational rules were incorporated into the Soil and Water Assessment Tool computer model (SWAT). SWAT is a distributed parameter rainfall‐runoff model capable of simulating the transpiration suppression effects of CO₂ enrichment. The new reservoir algorithms were calibrated using a 25‐year long historic record of basin climate and discharge records. Results demonstrate that it is possible to incorporate the operation of a highly regulated river system into a complex rainfall‐runoff model. The algorithms were then tested using extreme climate scenarios indicative of a prolonged drought, a short drought, and a ten percent increase in basin‐wide precipitation. It is apparent that the rules for operating the reservoirs will likely require modification if, for example, upper‐basin precipitation were to increase only ten percent under changed climate conditions.     

Analysis of Meteorological Drought Pattern During Different Climatic and Cropping Seasons in Bangladesh

Drought is one of the most frequent natural disasters in Bangladesh which severely affect agro‐based economy and people's livelihood in almost every year. Characterization of droughts in a systematic way is therefore critical in order to take necessary actions toward drought mitigation and sustainable development. In this study, standardized precipitation index is used to understand the spatial distribution of meteorological droughts during various climatic seasons such as premonsoon, monsoon, and winter seasons as well as cropping seasons such as Pre‐Kharif (March‐May), Kharif (May‐October), and Rabi (December‐February). Rainfall data collected from 29 rainfall gauge stations located in different parts of the country were used for a period of 50 years (1961‐2010). The study reveals that the spatial characteristics of droughts vary widely according to season. Premonsoon droughts are more frequent in the northwest, monsoon droughts mainly occur in the west and northwest, winter droughts in the west, and the Rabi and Kharif droughts are more frequent in the north and northwest of Bangladesh. It is expected that the findings of the study will support drought monitoring and mitigation activities in Bangladesh.