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1.
Environ Manage ; 59(4): 584-593, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27981355

RESUMO

The biological status of European lakes has not improved as expected despite up-to-date legislation and ecological standards. As a result, the realism of objectives and the attainment of related ecological standards are under doubt. This paper gets to the bottom of a river basin management plan of a eutrophic lake in Finland and presents the ecological and economic impacts of environmental and societal drivers and planned management measures. For these purposes, we performed a Monte Carlo simulation of a diffuse nutrient load, lake water quality and cost-benefit models. Simulations were integrated into a Bayesian influence diagram that revealed the basic uncertainties. It turned out that the attainment of good ecological status as qualified in the Water Framework Directive of the European Union is unlikely within given socio-economic constraints. Therefore, management objectives and ecological and economic standards need to be reassessed and reset to provide a realistic goal setting for management. More effort should be put into the evaluation of the total monetary benefits and on the monitoring of lake phosphorus balances to reduce the uncertainties, and the resulting margin of safety and costs and risks of planned management measures.


Assuntos
Monitoramento Ambiental/economia , Lagos/química , Modelos Teóricos , Rios/química , Qualidade da Água , Abastecimento de Água , Teorema de Bayes , Análise Custo-Benefício , Ecologia , Monitoramento Ambiental/legislação & jurisprudência , Monitoramento Ambiental/estatística & dados numéricos , União Europeia , Finlândia , Objetivos , Método de Monte Carlo , Fósforo/análise , Incerteza , Abastecimento de Água/economia , Abastecimento de Água/legislação & jurisprudência , Abastecimento de Água/estatística & dados numéricos
2.
Environ Manage ; 57(6): 1188-203, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26908125

RESUMO

Coal power generation capacity is expanding rapidly in the arid northwest regions in China. Its impact on water resources is attracting growing concerns from policy-makers, researchers, as well as mass media. This paper briefly describes the situation of electricity-water conflict in China and provides a comprehensive review on a variety of water resources management policies in China's coal power industry. These policies range from mandatory regulations to incentive-based instruments, covering water withdrawal standards, technological requirements on water saving, unconventional water resources utilization (such as reclaimed municipal wastewater, seawater, and mine water), water resources fee, and water permit transfer. Implementing these policies jointly is of crucial importance for alleviating the water stress from the expanding coal power industry in China.


Assuntos
Carvão Mineral , Centrais Elétricas , Recursos Hídricos/provisão & distribuição , Abastecimento de Água/métodos , China , Indústrias/normas , Centrais Elétricas/normas , Água do Mar/química , Águas Residuárias/química , Águas Residuárias/economia , Purificação da Água/métodos , Purificação da Água/normas , Abastecimento de Água/economia , Abastecimento de Água/normas
3.
Environ Sci Technol ; 49(22): 13724-32, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26461069

RESUMO

Holistic management of water and energy resources through energy and water quality management systems (EWQMSs) have traditionally aimed at energy cost reduction with limited or no emphasis on energy efficiency or greenhouse gas minimization. This study expanded the existing EWQMS framework and determined the impact of different management strategies for energy cost and energy consumption (e.g., carbon footprint) reduction on system performance at two drinking water utilities in California (United States). The results showed that optimizing for cost led to cost reductions of 4% (Utility B, summer) to 48% (Utility A, winter). The energy optimization strategy was successfully able to find the lowest energy use operation and achieved energy usage reductions of 3% (Utility B, summer) to 10% (Utility A, winter). The findings of this study revealed that there may be a trade-off between cost optimization (dollars) and energy use (kilowatt-hours), particularly in the summer, when optimizing the system for the reduction of energy use to a minimum incurred cost increases of 64% and 184% compared with the cost optimization scenario. Water age simulations through hydraulic modeling did not reveal any adverse effects on the water quality in the distribution system or in tanks from pump schedule optimization targeting either cost or energy minimization.


Assuntos
Água Potável , Abastecimento de Água/economia , Abastecimento de Água/métodos , California , Simulação por Computador , Custos e Análise de Custo , Qualidade da Água
4.
Sci Total Environ ; 524-525: 300-9, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25897735

RESUMO

Variability of household water-use costs across different sociodemographic groups in Puerto Rico is evaluated using census microdata from the Integrated Public Use Microdata Series (IPUMS). Multivariate analyses such as multiple linear regression (MLR) and factor analysis (FA) are used to classify, extract and interpret the household water-use costs. The FA results suggest two principal varifactors in explaining the variability of household water-use costs (64% in 2000 and 50% in 2010), which are grouped into a soft coefficient (social, economic and demographic characteristics of household residents, i.e., age, size, income, education) and a hard coefficient (dwelling conditions, i.e., number of rooms, units in the building, building age). The demographic profile of a high water-use household in Puerto Rico tends to be that of renters, people who live in larger or older buildings, people living in metro areas, or those with higher education level and higher income. The findings and discussions from this study will help decision makers to plan holistic and integrated water management to achieve water sustainability.


Assuntos
Recursos Hídricos/provisão & distribuição , Abastecimento de Água/economia , Demografia , Política Ambiental , Feminino , Humanos , Masculino , Análise Multivariada , Porto Rico , Fatores Socioeconômicos , Abastecimento de Água/estatística & dados numéricos
5.
Sci Total Environ ; 488-489: 477-83, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24377677

RESUMO

As part of a trans-disciplinary research project, a series of surveys and interventions were conducted in different arsenic-affected regions of rural Bangladesh. Surveys of institutional stakeholders identified deep tubewells and piped water systems as the most preferred options, and the same preferences were found in household surveys of populations at risk. Psychological surveys revealed that these two technologies were well-supported by potential users, with self-efficacy and social norms being the principal factors driving behavior change. The principal drawbacks of deep tubewells are that installation costs are too high for most families to own private wells, and that for various socio-cultural-religious reasons, people are not willing to walk long distances to access communal tubewells. In addition, water sector planners have reservations about greater exploitation of the deep aquifer, out of concern for current or future geogenic contamination. Groundwater models and field studies have shown that in the great majority of the affected areas, the risk of arsenic contamination of deep groundwater is small; salinity, iron, and manganese are more likely to pose problems. These constituents can in some cases be avoided by exploiting an intermediate depth aquifer of good chemical quality, which is hydraulically and geochemically separate from the arsenic-contaminated shallow aquifer. Deep tubewells represent a technically sound option throughout much of the arsenic-affected regions, and future mitigation programs should build on and accelerate construction of deep tubewells. Utilization of deep tubewells, however, could be improved by increasing the tubewell density (which requires stronger financial support) to reduce travel times, by considering water quality in a holistic way, and by accompanying tubewell installation with motivational interventions based on psychological factors. By combining findings from technical and social sciences, the efficiency and success of arsenic mitigation in general - and installation of deep tubewells in particular - can be significantly enhanced.


Assuntos
Arsênio/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Abastecimento de Água/estatística & dados numéricos , Bangladesh , Água Potável/química , Monitoramento Ambiental , Água Subterrânea/química , População Rural , Fatores Socioeconômicos , Purificação da Água/economia , Abastecimento de Água/economia
6.
Ciênc. Saúde Colet. (Impr.) ; Ciênc. Saúde Colet. (Impr.);18(7): 2119-2127, Jul. 2013. ilus, tab
Artigo em Português | LILACS | ID: lil-679611

RESUMO

As chamadas tecnologias sociais vêm sendo largamente usadas em muitos lugares do mundo como alternativa viável para que populações de baixa renda tenham acesso a oportunidades de ocupação e renda e outros aspectos relacionados à qualidade de vida, inclusive o saneamento básico. O presente trabalho realiza uma avaliação custo-benefício do uso de uma tecnologia de baixo custo para abastecimento de água potável utilizada em vários países, o sistema SODIS. O estudo foi realizado em comunidades ribeirinhas que vivem na área insular do município de Belém (PA), localizado na Amazônia brasileira. Os dados foram obtidos por meio de questionários respondidos por famílias moradoras de três ilhas: Jutuba, Nova e Urubuoca. Os resultados mostraram-se positivos, considerando a análise de custo-benefício do projeto, o que comprova a viabilidade econômica do uso do sistema SODIS na situação investigada.


The so-called social technologies have been widely used in many places around the world as a viable alternative for low-income populations to gain access to opportunities for employment and income and other aspects related to quality of life, including basic sanitation. This paper conducts a cost-benefit analysis of using a low cost technology for drinking water used in several countries, namely the SODIS system. The study was conducted in riverside communities living in the island area of Belem municipality, located in the Brazilian Amazon. Data were collected through questionnaires answered by families living on three islands: Jutuba, Nova and Urubuoca. The results were positive, considering the cost-benefit analysis of the project, which demonstrates the economic viability of using the SODIS system in the situation investigated.


Assuntos
Humanos , Promoção da Saúde/economia , Promoção da Saúde/métodos , Purificação da Água/economia , Purificação da Água/métodos , Abastecimento de Água/economia , Abastecimento de Água/normas , Brasil , Análise Custo-Benefício , Desinfecção , Características de Residência , Sociologia
7.
Water Res ; 45(12): 3712-22, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21565384

RESUMO

It is possible to optimize drinking water composition based on a valuation of the impacts of changed water quality. This paper introduces a method for assessing the potential for designing an optimum drinking water composition by the use of membrane desalination and remineralization. The method includes modeling of possible water quality blends and an evaluation of corrosion indices. Based on concentration-response relationships a range of impacts on public health, material lifetimes and consumption of soap have been valued for Perth, Western Australia and Copenhagen, Denmark. In addition to water quality aspects, costs of water production, fresh water abstraction and CO(2)-emissions are integrated into a holistic economic assessment of the optimum share of desalinated water in water supplies. Results show that carefully designed desalination post-treatment can have net benefits up to €0.3 ± 0.2 per delivered m(3) for Perth and €0.4(±0.2) for Copenhagen. Costs of remineralization and green house gas emission mitigation are minor when compared to the potential benefits of an optimum water composition. Finally, a set of optimum water quality criteria is proposed for the guidance of water supply planning and management.


Assuntos
Abastecimento de Água/análise , Abastecimento de Água/economia , Água/química , Carbonato de Cálcio/química , Dióxido de Carbono/análise , Precipitação Química , Dinamarca , Concentração de Íons de Hidrogênio , Minerais/química , Modelos Químicos , Solo/química , Água/normas , Austrália Ocidental
8.
Water Sci Technol ; 61(10): 2689-97, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20453343

RESUMO

Selecting cost-effective measures to regulate agricultural water pollution to conform to the Water Framework Directive presents multiple challenges. A bio-economic modelling approach is presented that has been used to explore the water quality and economic effects of the 2003 Common Agricultural Policy Reform and to assess the cost-effectiveness of input quotas and emission standards against nitrate leaching, in a representative case study catchment in Scotland. The approach combines a biophysical model (NDICEA) with a mathematical programming model (FSSIM-MP). The results indicate only small changes due to the Reform, with the main changes in farmers' decision making and the associated economic and water quality indicators depending on crop price changes, and suggest the use of target fertilisation in relation to crop and soil requirements, as opposed to measures targeting farm total or average nitrogen use.


Assuntos
Agricultura/métodos , Produtos Agrícolas/normas , Poluentes Ambientais/análise , Nitrogênio , Agricultura/economia , Agricultura/normas , Poluição Ambiental/economia , Política de Saúde/economia , Hordeum , Matemática , Modelos Teóricos , Orobanche , Rios , Escócia , Solanum tuberosum , Triticum , Verduras , Poluição da Água/economia , Abastecimento de Água/economia , Abastecimento de Água/normas
9.
Environ Manage ; 45(5): 1164-74, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20213232

RESUMO

In the United States, many state and federally funded conservation programs are required to quantify the water quality benefits resulting from their efforts. The objective of this research was to evaluate the impact of conservation practices subsidized by the Oklahoma Conservation Commission on phosphorus and sediment loads to Lake Wister. Conservation practices designed to increase vegetative cover in grazed pastures were evaluated using Landsat imagery and the Soil and Water Assessment Tool (SWAT). Several vegetative indices were derived from Landsat imagery captured before and after the implementation of conservation practices. Collectively, these indicators provided an estimate of the change in vegetative soil cover attributable to conservation practices in treated fields. Field characteristics, management, and changes in vegetative cover were used in the SWAT model to simulate sediment and phosphorus losses before and after practice implementation. Overall, these conservation practices yielded a 1.9% improvement in vegetative cover and a predicted sediment load reduction of 3.5%. Changes in phosphorus load ranged from a 1.0% improvement to a 3.5% increase, depending upon initial vegetative conditions. The use of fertilizers containing phosphorus as a conservation practice in low-productivity pastures was predicted by SWAT to increase net phosphorus losses despite any improvement in vegetative cover. This combination of vegetative cover analysis and hydrologic simulation was a useful tool for evaluating the effects of conservation practices at the basin scale and may provide guidance for the selection of conservation measures subsidized in future conservation programs.


Assuntos
Conservação dos Recursos Naturais/métodos , Água Doce/análise , Avaliação de Programas e Projetos de Saúde , Poluição da Água/prevenção & controle , Abastecimento de Água/normas , Agricultura/economia , Agricultura/normas , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/legislação & jurisprudência , Financiamento Governamental , Sedimentos Geológicos/análise , Modelos Teóricos , Oklahoma , Fósforo/análise , Poluição da Água/análise , Abastecimento de Água/economia , Abastecimento de Água/legislação & jurisprudência
10.
Adv Exp Med Biol ; 619: 259-73, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18461773

RESUMO

The tenets of watershed management--a focus on the land area linked to the water body, the incorporation of sound scientific information into the decision-making process and stakeholder involvement throughout the process--are well-suited for the management of cyanobacterial harmful algal blooms (C-HABs). The management of C-HABs can be viewed as having two main areas of focus. First, there is mitigation--control and/or removal of the bloom. This type of crisis response is an important component to managing active C-HABs and there are several techniques that have been successfully utilized, including the application of algicides, physical removal of surface scums and the mechanical mixing of the water column. While these methods are valuable because they address the immediate problem, they do not address the conditions that exist in the system that promote and maintain C-HABs. Thus, the second component of a successful C-HAB management strategy would include a focus on prevention. C-HABs require nutrients to fuel their growth and are often favored in longer-residence time systems with vertical stratification of the water column. Consequently, nutrients and hydrology are the two factors most commonly identified as the targets for prevention of C-HABs. Management strategies to control the sources, transformation and delivery of the primary growth-limiting nutrients have been applied with success in many areas. The most effective of these include controlling land use, maintaining the integrity of the landscape and applying best management practices. In the past, notable successes in managing C-HABs have relied on the reduction of nutrients from point-sources. Because many point sources are now well-managed, current efforts are focused on non-point source nutrient reduction, such as runoff from agricultural and urban areas. Non-point sources present significant challenges due to their diffuse nature. Regardless of which techniques are utilized, effective watershed management programs for decreasing the prevalence of C-HABs will require continuing efforts to integrate science and management activities. Ultimately, it is increased coordination among stakeholders and scientists that will lead to the development of the decision-making tools that managers require to effectively weigh the costs and benefits of these programs.


Assuntos
Cianobactérias/patogenicidade , Eutrofização , Água Doce/microbiologia , Análise Custo-Benefício , Ecossistema , Meio Ambiente , Humanos , Nitrogênio/análise , Fósforo/análise , Abastecimento de Água/economia
11.
J Environ Health ; 70(7): 46-50, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18348392

RESUMO

It is estimated that one billion people worldwide do not have access to treated drinking water. This paper reports on an investigation into the potential of indigenous or natural water treatment methods as alternatives to conventional chemical water treatment methods. The seeds of five natural plant species--Vigna unguiculata, Phaseolus mungo, Glycine max, Pisum sativam, and Arachis hypogea--were evaluated for the removal of turbidity, and their efficiency was compared with that of alum. The use of a solar energy-saving method to disinfect drinking water--leaving it to heat under the sun to reduce bacteria colonies--also was evaluated, The study revealed that for raw water with turbidity of 482 nephelometric turbidity units, coagulation with seed extracts from natural plant species reduced natural turbidity by 96.7 to 100 percent when the seed extract was used as the primary coagulant and by 100 percent when it was used as a coagulant aid. The study showed further that natural coagulants were as effective as commercial alum [Al2(SO4)3] and even superior for clarification because the optimum dosage was low compared with that of alum. Leaving samples of water clarified by natural coagulants on a black-painted roof for 8 hours achieved up to 100 percent bacteria kill.


Assuntos
Purificação da Água/métodos , Abastecimento de Água/normas , Filtração/instrumentação , Humanos , Extratos Vegetais , Sementes , Inquéritos e Questionários , Tanzânia , Purificação da Água/economia , Purificação da Água/normas , Abastecimento de Água/economia
12.
J Environ Manage ; 89(2): 86-98, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17923250

RESUMO

Traditional olive orchards account for a large share of the area under olives in the EU, particularly in marginal areas, like those analysed in the OLIVERO project. In general, traditional olive growing can be described as a low-intensity production system, associated with old (sometimes very old) trees, grown at a low density, giving small yields and receiving low inputs of labour and materials. Though such systems are environmentally sustainable, their economic viability has become an issue, since EU policies favour more intensive and competitive systems. Orchards that have not been intensified seem to be threatened by the recent reform of the EU olive and olive oil policy, as income support has been decoupled from production. The main purpose of this paper is to identify the present constraints to traditional olive growing, and to recommend some private and public interventions to prevent its abandonment. During the OLIVERO project, traditional olive production systems were identified and described in five target areas (Trás-os-Montes--Portugal, Cordoba and Granada/Jaen--Spain, Basilicata/Salerno--Italy, and West Crete--Greece). The causes and consequences of abandonment are discussed, based on the analysis of the costs and returns, which revealed that these systems are barely economically sustainable. Their viability is only assured if reduced opportunity costs for family labour are accepted, and the olive growing is part-time. Based on these results, recommendations are made to prevent the abandonment of traditional olive growing and to preserve its environmental benefits.


Assuntos
Agricultura/economia , Conservação dos Recursos Naturais , Olea/crescimento & desenvolvimento , Agricultura/métodos , Altitude , Análise Custo-Benefício , Custos e Análise de Custo , Tomada de Decisões , Ecossistema , Humanos , Região do Mediterrâneo , Formulação de Políticas , Fatores Socioeconômicos , Abastecimento de Água/economia , Recursos Humanos
13.
J Environ Manage ; 88(2): 219-52, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17449168

RESUMO

Water pinch analysis (WPA) is a well-established tool for the design of a maximum water recovery (MWR) network. MWR, which is primarily concerned with water recovery and regeneration, only partly addresses water minimization problem. Strictly speaking, WPA can only lead to maximum water recovery targets as opposed to the minimum water targets as widely claimed by researchers over the years. The minimum water targets can be achieved when all water minimization options including elimination, reduction, reuse/recycling, outsourcing and regeneration have been holistically applied. Even though WPA has been well established for synthesis of MWR network, research towards holistic water minimization has lagged behind. This paper describes a new holistic framework for designing a cost-effective minimum water network (CEMWN) for industry and urban systems. The framework consists of five key steps, i.e. (1) Specify the limiting water data, (2) Determine MWR targets, (3) Screen process changes using water management hierarchy (WMH), (4) Apply Systematic Hierarchical Approach for Resilient Process Screening (SHARPS) strategy, and (5) Design water network. Three key contributions have emerged from this work. First is a hierarchical approach for systematic screening of process changes guided by the WMH. Second is a set of four new heuristics for implementing process changes that considers the interactions among process changes options as well as among equipment and the implications of applying each process change on utility targets. Third is the SHARPS cost-screening technique to customize process changes and ultimately generate a minimum water utilization network that is cost-effective and affordable. The CEMWN holistic framework has been successfully implemented on semiconductor and mosque case studies and yielded results within the designer payback period criterion.


Assuntos
Conservação dos Recursos Naturais/economia , Modelos Econômicos , Abastecimento de Água/economia , Algoritmos , Cidades , Análise Custo-Benefício , Gerenciamento de Resíduos
14.
J Environ Manage ; 71(2): 95-122, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15135946

RESUMO

This paper presents an analysis of the site restoration techniques that may be employed in a variety of contaminated site cleanup programs. It is recognized that no single specific technology may be considered as a panacea for all contaminated site problems. An easy-to-use summary of the analysis of the important parameters that will help in the selection and implementation of one or more appropriate technologies in a defined set of site and contaminant characteristics is also included.


Assuntos
Poluição Ambiental/economia , Poluição Ambiental/prevenção & controle , Resíduos Perigosos , Petróleo , Gerenciamento de Resíduos/métodos , Guias como Assunto , Poluentes do Solo/economia , Estados Unidos , Gerenciamento de Resíduos/economia , Poluição Química da Água/economia , Abastecimento de Água/economia
15.
J Environ Manage ; 68(1): 95-107, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12767865

RESUMO

Abstractions of surface and groundwater for irrigation in Scotland are currently subject to control in only two small catchments. Under the terms of the EU Water Framework Directive, it will be necessary to introduce new legislation to control abstractions elsewhere. To help in the development of appropriate policy for Scotland a study has been carried out to examine the significance of irrigation and the effectiveness of different types of control strategies in terms of the economics of potato cropping and stream hydrology in Scotland. This paper presents the findings of the hydrological study and highlights some of the spatial and temporal issues that need to be considered in the selection of control mechanisms, if they are to be successful in achieving objectives for environmental improvement. The study was focussed on two catchments in the east of Scotland, the Tyne and West Peffer. The effectiveness of several different abstraction control strategies was examined to see how stream flows in the catchment would be modified by their implementation. The results of the study demonstrated that the West Peffer catchment in particular is significantly affected by irrigation abstractions. Control mechanisms based on allowable monthly abstraction volumes and flow-based abstraction bans would be of considerable help in restoring stream flows to their natural levels, but would modify the hydrological regime in slightly different ways. A spatial analysis of stream flows demonstrated that implementation of controls based on a single monitoring point may be ineffective at maintaining acceptable levels of flow throughout the catchment and that this may require a tighter control at the monitoring point.


Assuntos
Agricultura/economia , Modelos Teóricos , Movimentos da Água , Abastecimento de Água/economia , Custos e Análise de Custo , Meio Ambiente , Escócia , Solo , Solanum tuberosum , Fatores de Tempo
16.
Zb Zgodovino Naravoslovja Teh ; 15-16: 211-26, 2002.
Artigo em Esloveno | MEDLINE | ID: mdl-17228488

Assuntos
Educação de Pós-Graduação em Medicina , Educação Médica , Planejamento de Instituições de Saúde , História do Século XX , Maternidades , Hospitais Militares , Governo Local , Tocologia , Orfanatos , Farmácias , Médicos , Prática Profissional , Saúde Pública , Abastecimento de Água , Áustria , Educação Médica/economia , Educação Médica/história , Educação Médica/legislação & jurisprudência , Educação de Pós-Graduação em Medicina/economia , Educação de Pós-Graduação em Medicina/história , Educação de Pós-Graduação em Medicina/legislação & jurisprudência , Planejamento de Instituições de Saúde/economia , Planejamento de Instituições de Saúde/história , Planejamento de Instituições de Saúde/legislação & jurisprudência , História da Medicina , História do Século XIX , Hospitais/história , Maternidades/economia , Maternidades/história , Maternidades/legislação & jurisprudência , Hospitais Militares/economia , Hospitais Militares/história , Hospitais Militares/legislação & jurisprudência , Tocologia/economia , Tocologia/história , Tocologia/legislação & jurisprudência , Orfanatos/economia , Orfanatos/história , Orfanatos/legislação & jurisprudência , Farmácias/economia , Farmácias/história , Farmácias/legislação & jurisprudência , Médicos/economia , Médicos/história , Médicos/legislação & jurisprudência , Prática Profissional/economia , Prática Profissional/história , Prática Profissional/legislação & jurisprudência , Saúde Pública/educação , Saúde Pública/história , Saúde Pública/legislação & jurisprudência , Prática de Saúde Pública/história , Prática de Saúde Pública/legislação & jurisprudência , Eslovênia/etnologia , Médicos Veterinários/economia , Médicos Veterinários/história , Médicos Veterinários/legislação & jurisprudência , Abastecimento de Água/economia , Abastecimento de Água/história , Abastecimento de Água/legislação & jurisprudência
17.
J Dairy Sci ; 83(9): 2160-9, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11003251

RESUMO

The objectives of this paper were to use a linear programming model previously described to evaluate different alternatives for reducing excess nutrients that may influence water quality on a case study farm (300 lactating cows on 430 ha of cropland growing alfalfa, grass, and corn). Several alternatives perceived to influence farm nutrient balance were evaluated for their potential to reduce N and P mass balance. Dividing lactating cow diets into three groups according to their level of milk production versus a one-group total mixed ration decreased mass balance (tonne/yr) from 51.7 to 44.7 for N, from 6.7 to 6.1 for P and from 16.2 to 14.8 for K with little influence on return over feed costs. Increasing forage quality (lower neutral detergent fiber and higher crude protein) did not improve N balance because of the increased N fixation from the air to the soil, but it increased returns over feed costs by $31,385. Improving yields to the maximum potential for the farm reduced mass balance by 29, 51, and 100% for N, P, and K, respectively, and increased returns over feed costs by $70,579. Changing the crop hectare proportions to more corn and less alfalfa reduced N and K balances by 19 and 29%, respectively, and increased returns over feed costs $39,383. Increasing annual milk production 10% by increasing milk production per head 10% compared with increasing animal numbers at the current average milk production per cow until total milk increased 10% gave $34,132 more return over feed costs with less N, P, and K retained on the farm.


Assuntos
Agricultura/normas , Bovinos/metabolismo , Modelos Biológicos , Nitrogênio/metabolismo , Fósforo/metabolismo , Agricultura/economia , Agricultura/métodos , Ração Animal/economia , Animais , Análise Custo-Benefício , Produtos Agrícolas/economia , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Feminino , Lactação , Medicago sativa , Leite , Programação Linear , Abastecimento de Água/economia , Abastecimento de Água/normas , Zea mays
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