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Yogesh P. Khare Christopher J. Martinez Gurpal S. Toor 《Journal of the American Water Resources Association》2012,48(6):1276-1293
Abstract: Spatial distribution of land use can have a substantial effect on surface and groundwater quality. Our objective was to test for trends in flow components and water quality related to changes in land use in the Alafia and Hillsborough River watersheds in Florida, USA, over the period 1974‐2007. In addition, water quality statistics were evaluated in the perspective of numeric water quality criteria and proposed reclassification of segments of the Alafia River. Trends in 10 water quality parameters and three discharge variables were evaluated using a nonparametric trend detection test. Results of land use analysis indicated substantial urbanization and loss of agricultural land in the study area. Discharge variables did not exhibit significant trends, whereas trends in the majority of water quality concentrations were negative or nonsignificant with total nitrogen and total Kjeldahl nitrogen as exceptions showing positive trends. Changes in nutrient pathways could not be clearly identified. Considering recently promulgated numeric nutrient criteria and standards for dissolved fluoride, much of the Alafia River was found to be out of compliance. While there were land use changes and changes in water quality over the study period, it was difficult to identify a direct cause‐effect relationship. Responses to regulatory efforts, such as the Clean Water Act and improvements in phosphate mining practices, may have had greater impacts on water quality than changes in land use. 相似文献
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可持续发展应分阶段分层次地进行;为增强区域土地可持续利用,相关环境政策的制定应遵循可持续发展原则;区域土地可持续利用的评价流程与环境政策循环模式;这一领域的相关法律问题;最后提出了一些建议。 相似文献
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本文通过对我国土地现状、土地政策的特点以及土地政策与法律的区别来阐述土地政策亟需规范的必要性,并提出了相应的对策、措施,以期有助于缓解我国目前土地政策因缺乏规范、监控而造成大量土地被非法征用、开发、转让的局面。 相似文献
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Ribolzi O Cuny J Sengsoulichanh P Mousquès C Soulileuth B Pierret A Huon S Sengtaheuanghoung O 《Environmental management》2011,47(2):291-302
Improving access to clean water has the potential to make a major contribution toward poverty reduction in rural communities
of Lao P.D.R. This study focuses on stream water quality along a Mekong basin tributary, the Houay Xon that flows within a
mountainous, mosaic land-use catchment of northern Lao P.D.R. To compare direct water quality measurements to the perception
of water quality within the riparian population, our survey included interviews of villagers. Water quality was found to vary
greatly depending on the location along the stream. Overall, it reflected the balance between the stream self-cleaning potential
and human pressure on the riparian zone: (i) high bacteria and suspended load levels occurred where livestock are left to
free-range within the riparian zone; (ii) very low oxygen content and high bacteriological contamination prevailed downstream
from villages; (iii) high concentrations of bacteria were consistently observed along urbanized banks; (iv) low oxygen content
were associated with the discharge of organic-rich wastewater from a small industrial plant; (v) very high suspended load
and bacteria levels occurred during flood events due to soil erosion from steep cultivated hill slopes. Besides these human
induced pollutions we also noted spontaneous enrichments in metals in wetland areas fed by dysoxic groundwater. These biophysical
measurements were in agreement with the opinions expressed by the majority of the interviewees who reported poor and decreasing
water quality in the Houay Xon catchment. Based on our survey, we propose recommendations to improve or maintain stream water
quality in the uplands of northern Lao P.D.R. 相似文献
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Klaus Peter Rippe 《Journal of Agricultural and Environmental Ethics》2000,12(1):71-80
In the public debate concerning novel foods, someconsumer groups claim a consumer right to have accessto certain kinds of food in the market. To discusssuch statements, the paper identifies the reasons thatmay justify liberal states to regulate food. Althoughit defends certain paternalistic activities, itfavours an autonomy-centred food policy. Autonomy andconsumer sovereignty require that certain conditionsare fulfilled. It may be argued that one suchcondition is that the consumer should have choices.Against this position, the paper defends the view thatliberty rights to choose are limited to areas whichare of great importance for personal identity and thegood life. Local decisions in the area of foodconsumption do not have such importance, though globalones may have it. But even if this were true,government activity to protect such liberties shouldbe limited to the guarantee of formal conditions forthe good life of persons. It is not a legitimate taskof the government to safeguard specific conceptions ofthe good life. 相似文献
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Melaleuca quinquenervia, is expanding rapidly throughout seasonally wet areas of southern Florida (USA), including the littoral zone of Lake Okeechobee.
Natural resource managers are concerned that a lower lake level regulation schedule under consideration for Lake Okeechobee,
while potentially beneficial to overall ecosystem health, might increase the rate of Melaleuca expansion. To investigate this possibility, Melaleuca saplings (harvested from the littoral zone) and 7-week-old seedlings (grown from harvested seeds) were subjected to various
hydroperiod treatments in replicated mesocosms. Hydroperiod treatments were selected based on a simulation of historical water
level variations. Saplings grew taller under longer hydroperiods with fluctuating water levels, including periods of submersion.
Time since germination affected the response of seedlings to inundation. Submersed 7-week-old seedlings grew slower and had
less biomass than submersed 12-week-old seedlings, yet mortality was low at both ages. Melaleuca's plasticity allows it to adapt to hypoxic, aquatic conditions by means of aquatic heterophylly and adventitious roots. Algae
and drought also increased mortality. Based on faster growth of Melaleuca under longer hydroperiods and its adaptability to seasonal flooding, a lower lake regulation schedule may not stimulate its
expansion. Therefore, water levels should not be manipulated only to control Melaleuca. Control of Melaleuca should continue using current practices such as manual removal or chemical treatment. 相似文献
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Peter Moser 《Local Environment》2013,18(4):453-467
The concluding document of the Rio conference in 1992, Agenda 21 for sustainable development, is implemented mainly at the local level in Germany. 'Sustainable development' is a model for the socially fair, economically competitive and ecologically viable development of the world. Local Agenda 21 (LA21) is a new municipal urban development process in which cities and their inhabitants orientate themselves to the model of sustainable development. Analysis of the LA21 process in Germany, and in particular that of the city of Osnabrück, shows deficits between the requirement of achieving sustainability and its practical realisation. Only a marginal development in the direction of sustainability has taken place. Concepts are lacking and the LA21 process is insufficiently integrated into conventional urban planning. Suggestions for the improvement of the LA21 process include the development of a concrete concept, together with the continuation of practical examples, the integration of four main areas (the environment, the social, the economy and the less developed world) and the strengthening of the popular themes in the LA21 process (such as climate protection and less developed countries' politics). El documento final de la conferencia de Rio en 1992 "La Agenda 21 para el desarrollo sostenible", es inplementado principalmente a nivel local en Alemania. "Desarrollo Sostenible" es una modelo para el desarrollo del mundo socialmente justo, ecónomicamente competitivo y ecológicamente viable. La "Agenda Local 21" es un nuevo proceso de desarrollo urbano municipal, en el cual las ciudades y sus habitantes se orientan hacia el modelo de desarrollo sostenible. El análisis del proceso de la Agenda Local 21 en Alemania y en particular el de la ciudad de Osnabrück muestra deficits entre el requerimiento de logro de sostenibilidad y su realización práctica. Solo un desarrollo marginal en la dirección de sostenibilidad ha sido llevado a cabo. Hay carencia de conceptos y el proceso de la Agenda Local 21 es insuficientemente integrado en la planeacio´n urbana convencional. Sugerencias para un mejoramiento del proceso de la AL 21 incluyen el desarrollo de un concepto concreto junto con la continuación de ejemplos practicos, integración de cuatro áreas principales (ambiental, social, económica, y el mundo menos desarrollado) y fortalecimiento de temas populares en el proceso de la AL 21 (tales como protección del clima y políticas de paises menos desarrollados). 相似文献
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The effects of water and fertilizer best management practices (BMPs) have not been quantified for groundwater nitrogen (N) beneath seepage irrigated vegetable fields with shallow water table environments. This effect was evaluated by a 3-yr study conducted in the Flatwoods of south Florida for watermelon ( cv. Mardi Gras and Tri-X 313) and tomato ( cv. BHN 586) using three treatments of water and inorganic fertilizer N (N) rates: (i) high fertilizer and water rates with seepage irrigation (HR), (ii) recommended fertilizer and water rates (BMP) with seepage irrigation (RR); and (iii) RR with subsurface drip irrigation (RR-SD). These treatments were implemented on six hydraulically isolated plots. The N rate treatments for high (HR) and recommended (RR and RR-SD) were based on a grower survey and BMP recommendations, respectively. Water applied, water table depth, and soil moisture content were regularly monitored for each treatment. Plant, soil, and groundwater N sampling and analyses were conducted for each season of the 3-yr study. The average water applied in HR (187 cm) was greater than RR (172 cm) and RR-SD (94 cm). Soil N maintained in crop beds for HR was significantly higher than RR and RR-SD. Soil solution analyses showed that N leached beneath HR (112 mg L) was greater ( = 0.053) than RR (76 mg L) and RR-SD (88 mg L). Shallow groundwater concentrations of dissolved inorganic nitrogen (NH-N + NO-N) were higher ( = 0.02) in HR (37 mg L) compared with RR (15 mg L) and RR-SD (19 mg L). Decreased N and water table levels can improve groundwater quality by reducing N leachate in shallow water table environments with seepage irrigated vegetable production systems. 相似文献
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We analyzed the effects of changes in land cover on the water balance in Spain’s Marina Baixa County, on the Mediterranean
coast. To reveal how different land management strategies have affected the area’s environment, four municipalities within
the same catchment were studied: Benidorm, Callosa d’en Sarrià, Beniardà, and Guadalest. In the municipalities of Callosa
and Benidorm, the proportion of the area covered by woodland declined by 4.2% and 30.2%, respectively, and woodland was replaced
by agriculture and urban development. The abandonment of farmland produced a 17% increase in the proportion of the area covered
by vegetation in Guadalest and Beniardá, where frequent forest fires have exacerbated a decrease in the area of pine woodland.
Tourism development in Benidorm has been accompanied by an increase in the transportation infrastructure and by an expansion
of areas with an impermeable surface, with the lowest level of infiltration into the aquifer system. These changes have generated
a net water deficit in Callosa and Benidorm of more than 6 Mm3/year, creating a high demand for water imported from other municipalities (Guadalest and Beniardá) or from outside of the
county to maintain the sustainability of the current water management strategies. The Marina Baixa case study is representative
of many of the world’s coastal areas that are undergoing rapid urban development based on an inappropriate understanding of
human progress based mainly on economic development and thus provides insights into water management in other areas. 相似文献
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当前世界各国都面临着土地资源不可持续利用的严峻考验。从土地污染的角度,讨论了土地资源的可持续问题。工业“三废”的排放、城市化进程和土地污染防治法律的滞后是引起土地资源不可持续利用的重要原因。为了防治土地污染,促进土地资源的可持续利用,许多国家都已经建立了相对完善的保护体系。着重介绍了美国、日本、德国等发达国家在治理和防治土壤污染方面的经验,并在此基础上对目前我国土地资源的可持续利用提出了建议。 相似文献
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太湖水土资源保护和经济发展研究 总被引:2,自引:0,他引:2
本文对江苏省太湖地区水土资源利用现状及其与经济发展之间的协调性进行了系统分析,提出了该区今后在保护水土资源的同时促进社会经济发展的对策. 相似文献
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Neubauer CP Hall GB Lowe EF Robison CP Hupalo RB Keenan LW 《Environmental management》2008,42(6):1101-1114
The St. Johns River Water Management District (SJRWMD) has developed a minimum flows and levels (MFLs) method that has been
applied to rivers, lakes, wetlands, and springs. The method is primarily focused on ecological protection to ensure systems
meet or exceed minimum eco-hydrologic requirements. MFLs are not calculated from past hydrology. Information from elevation
transects is typically used to determine MFLs. Multiple MFLs define a minimum hydrologic regime to ensure that high, intermediate,
and low hydrologic conditions are protected. MFLs are often expressed as statistics of long-term hydrology incorporating magnitude
(flow and/or level), duration (days), and return interval (years). Timing and rates of change, the two other critical hydrologic
components, should be sufficiently natural. The method is an event-based, non-equilibrium approach. The method is used in
a regulatory water management framework to ensure that surface and groundwater withdrawals do not cause significant harm to
the water resources and ecology of the above referenced system types. MFLs are implemented with hydrologic water budget models
that simulate long-term system hydrology. The method enables a priori hydrologic assessments that include the cumulative effects
of water withdrawals. Additionally, the method can be used to evaluate management options for systems that may be over-allocated
or for eco-hydrologic restoration projects. The method can be used outside of the SJRWMD. However, the goals, criteria, and
indicators of protection used to establish MFLs are system-dependent. Development of regionally important criteria and indicators
of protection may be required prior to use elsewhere. 相似文献
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Courtney G. Flint Amber Spackman Jones Jeffery S. Horsburgh 《Journal of the American Water Resources Association》2017,53(5):988-996
Integrating social and hydrologic sciences for understanding water systems is challenged by data management complexities. Contemporary mandates for open science and data sharing necessitate better understanding of the implications of social science data types. In the context of an interdisciplinary water research program that endeavors to integrate and share social science and biophysical data, we highlight the array of data types and issues associated with social water science. We present a multi‐dimensional classification of social water science data that provides insight into data management considerations for each data type. Recommendations for cyberinfrastructure, planning, and policy are offered. 相似文献
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L. G. Firbank M. G. Telfer B. C. Eversham H. R. Arnold 《Journal of environmental management》1994,42(4)
The set-aside scheme of the E.C. is a way of dealing with the socio-economic problem of food surpluses, but it also presents opportunities for environmental benefits. To help target set-aside policies, three groups of species (scarce plants, butterflies and grasshoppers) were analysed by present and past distribution and by habitat. In those biotopes which could be restored using set-aside land, chalk grassland has shown the greatest decline of scarce plants, and the two insect groups have declined the most in heathland, water-fringe vegetation and woodland edges. However, declines were also observed for other biotopes. These and other data suggest that conservation efforts on a set-aside land should not be concentrated on a particular kind of habitat, but should address a diversity of habitats in a diversity of locations. This conclusions has been used to help defined the 1993 set-aside schemes for the U.K. 相似文献