Spelling suggestions: "subject:"0nvironmental impacts"" "subject:"0nvironmental lmpacts""
11 |
Comparative analysis of electricity generating technologies with regards to environmental burdensPapadopoulos, Ioannis January 2010 (has links)
In the last couple of decades, there has been an increased awareness of the effects that electricity generation has on the environment through the emission of greenhouse gases and the depletion of natural resources. This realisation, coupled with an increased drive towards ensuring the sustainability of the energy supply system, has lead many, including the United Kingdom government to investigate the options for moving away from traditional fossil fuel-burning generation methods towards “lowcarbon” generators, such as renewables and nuclear power. Specifically, wind power, the more mature systems (with the exception of hydro power) of the available renewable energy supply, and nuclear power, a technology seen as producing large amounts of electricity with very few associated greenhouse emissions, have been promoted but also pitted against each other by analysts and policy makers. This work aims to provide a balanced analysis of wind power and nuclear power with respect to their effects on the natural environment. As such, modeling has been undertaken of a Generation III+ nuclear reactor, an onshore wind farm located in southern Scotland and an offshore wind farm near the Thames estuary while environmental indicators have been created to permit the comparative assessment of these three electricity generation technologies, in a U.K. context. These indicators thus facilitate an assessment of the energy requirements, the associated greenhouse gas emissions, the natural resource requirements, as well as the displaced carbon dioxide emissions from operation of each power plant. A parametric analysis has also been conducted to show the range of likely variations in each indicator’s values. The results of this research show that all three technologies demonstrate similar performance with respect to their energetic and environmental impacts. More specifically, the wind farms demonstrate better energy gain ratios than the nuclear power plant when they are credited for not depleting non-renewable fuel sources. The wind farms also are shown to pay back their energy investments faster than the nuclear power plant. On the other hand, the nuclear power plant is found to produce slightly lower greenhouse gas emissions than either onshore or offshore wind farms. With respect to the assessment of natural resource depletion, it is estimated that both wind farms need more land per unit of electricity produced than the nuclear power plant, but all three power plants permanently sequester similar amounts of water. The wind farms and the nuclear power plant are found to have similar performance with respect to their material requirements, while the calculation of the avoided emissions factors for all technologies are of similar orders of magnitude. All results are shown to be highly sensitive to the assumptions made about the prospective lifecycles, and as such caution should be exercised when drawing conclusions about any comparative advantages. Nethertheless both technologies are clearly shown to have lower environmental impacts than traditional electricity generation technologies.
|
12 |
Impacto da vegetação nos microclimas urbanos em função das interações solo-vegetação-atmosfera / The impact of vegetation on urban microclimates as a function of soil-vegetation-atmosphere interactionsPaula Shinzato 29 May 2014 (has links)
Este trabalho tem por objetivo quantificar o impacto da vegetação nos microclimas urbanos abaixo do dossel, em função das interações solo-vegetação-atmosfera. Essas interações consideram os efeitos: 1) do dossel propriamente dito, expressos pelas variáveis índice de área foliar - IAF (Leaf Area Index - LAI) e distribuição geométrica das aberturas na copa (gap fraction); 2) da cobertura do solo, expressa pela composição do solo, sua temperatura e teor de umidade, e 3) das variáveis microclimáticas locais (temperatura do ar, umidade do ar, radiação solar, temperatura radiante media, temperatura superficial, direção e velocidade dos ventos). Considerando-se que o impacto da vegetação nos microclimas urbanos é função das interações solo-vegetação-atmosfera, e tendo em vista resultados de estudos anteriores, a hipótese deste trabalho é que, para o clima de São Paulo, em função dos processos de evapotranspiração e do sombreamento, a redução na temperatura do ar abaixo do dossel em parques urbanos será de cerca de 1o C e a redução da temperatura superficial será de cerca de 20oC, ambas em relação às áreas não sombreadas pela vegetação, e que esses efeitos limitam-se à borda do parque sob condições de baixa velocidade do vento, de cerca de 1 m/s. O método é 1) indutivo, por meio de medições de campo durante o período de dias quentes e frios no Parque Tenente Siqueira Campos (Trianon), na cidade de São Paulo, para o registro de dados microclimáticos e para o levantamento das variáveis do dossel e do solo; e 2) dedutivo, com a calibração entre dados medidos e simulados pelo modelo ENVI-met 3.1 Beta 5 e a simulação de diferentes cenários, variando-se as características do dossel. Para se estimar a densidade foliar média das copas foram adotados dois métodos não-destrutivos indiretos: a medição do IAF com o equipamento LAI-2000 (LI-COR) e a análise das fotos hemisféricas, utilizando-se o aplicativo Can-Eye. De acordo com os resultados das simulações, variando-se as caraterísticas do dossel, verificou-se uma redução máxima de 1ºC na temperatura do ar e de 19°C na temperatura superficial, ao se comparar os valores obtidos abaixo de uma copa densa (forma elíptica e IAF 5m2/m2) em relação às condições do entorno, fora do parque. Esse efeito se estende por, no máximo, 5m de distância a partir dos limites do parque, com velocidade do ar de 1m/s e umidade de 40% na camada superficial do solo (0-20cm). Foi feita a aplicação do TEP - Temperatura Equivalente Percebida e verificou-se que a redução de 1°C na temperatura do ar pode representar de 3°C a 5°C no conforto térmico das pessoas. Esses resultados comprovam a hipótese inicial e mostram não apenas a importância do tipo de vegetação escolhida (formato da copa, IAF e distribuição geométrica das aberturas na copa) como as características do meio em que ela está inserida (condições microclimáticas locais e de solo). Os resultados podem contribuir para a formulação de políticas públicas visando à mitigação dos efeitos de aquecimento urbano, particularmente diurnos, em climas tropicais. / The objective of this work is to quantify the impact of vegetation on urban microclimates, under the canopy, due to soil-vegetation-atmosphere interactions. It considers the following effects: 1) the canopy itself, expressed by the variable leaf area index - LAI and the geometric openness distribution in the canopy (gap fraction); 2) the soil coverage, expressed by soil composition, soil temperature and soil humidity, and 3) the local microclimatic variables (air temperature, humidity, solar radiation, mean radiant temperature, surface temperature, wind direction and wind speed). Considering the impact of vegetation on urban microclimates as a function of soil-vegetation-atmosphere, and based on the outcomes of preview studies, this work starts from the hypothesis that for São Paulo climate and as a result of evapotranspiration and shadowing process, the reduction of air temperature under the canopy will be between 1°C to 2°C and for surface temperature, it will be around 20°C, both in relation to an area without tree shadowing. These effects are restricted to the borders of the park, especially under the conditions of low wind speed, approximately 1m/s. The methods are: 1) inductive, based on field measurements in summer and winter at Tenente Siqueira Campos Park (Trianon Park), in the city of São Paulo, registering microclimatic data and collecting information for canopy and soil; and 2) deductive, with the calibration of measured and simulated data by ENVI-met 3.1 Beta 5 and the simulation for different scenarios varying the canopy characteristics. To estimate the average leaf density for trees canopy two no-destructive indirect methods were applied: measurement of LAI using the equipment LAI-2000 (LI-COR) and the analysis of hemispheric photographs, using a software application Can-Eye. According to the simulation results, for different characteristics for canopy, it could be verified a maximum reduction of 1ºC in air temperature and 19°C for surface temperature, when comparing the obtained value under a dense canopy (elliptical form and LAI of 5m2/m2) to the conditions on the street. The maximum extension of these effects were up to 5m from the limits of the park, considering 1m/s for wind speed and 40% for soil humidity in the upper layer (0-20cm). The thermal index TEP calculated and it could be seen that the reduction of 1°C for air temperature can represent from 3°C to 5°C in terms of thermal comfort of people. By these results, the initial hypothesis has proven to be correct and showed not only the importance of the type of vegetation selected (canopy form, LAI values and geometric distribution of canopy openness) but also the characteristics of the surrounding environment (microclimatic and soil conditions). Furthermore, it will contribute to formulate public politics aiming to mitigate urban warming effect, mainly during daytime, in tropical cities.
|
13 |
Trace metal speciation in the Pieman River catchment, Western Tasmania.Denney, Susan, susan.denney@deakin.edu.au January 2000 (has links)
The Pieman River catchment has seen continuous mining of economic deposits of gold, silver, lead, copper, zinc and tin since the 1870s. Tributaries of this river which receive mining effluent, either directly or from acid mine drainage (AMID), have total metal concentrations considerably above background levels and are of regulatory concern. The lower Pieman River is however classified as a State Reserve in which recreational fishing and tourism are the major activities. It is therefore important that water entering the lower Pieman River from upstream hydroelectric impoundments is of high quality.
Metals in natural waters exist in a variety of dissolved, colloidal and particulate forms. The bioavailability and hence toxicity of heavy metal pollutants is very dependant on their physico form. Knowledge of the speciation of a metal in natural aquatic environments is therefore necessary for understanding its geochemical behaviour and biological availability.
Complexation of metal ions by natural ligands in aquatic systems is believed to play a significant role in controlling their chemical speciation. This study has investigated temporal and spatial variation in complexation of metal ions in the Pieman River. The influence of pH, temperature, organic matter, salinity, ionic strength and time has been investigated in a series of field studies and in laboratory-based experiments which simulated natural and anthropogenic disturbances.
Labile metals were measured using two techniques in various freshwater and estuarine environments. Diffusive gradients in thin-films (DGT) allowed in situ measurement of solution speciation whilst differential pulse anodic stripping voltammetry (DPASV) was used to measure labile metal species in water samples collected from the catchment.
Organic complexation was found to be a significant regulating mechanism for copper speciation and the copper-binding ligand concentration usually exceeded the total copper concentration in the river water. Complexation was highly dependent on pH and at the river-seawater interface was also regulated by salinity, probably as a result of competitive complexation by major ions in seawater (eg. Ca 2+ ions).
Zinc complexation was also evident, however total zinc concentrations in the water column often far exceeded the potential binding capacity of available ligands. In addition to organic complexation, Zn speciation may also be associated with adsorption by flocculated or resuspended colloidal Mn and/or Fe oxyhydroxides.
Metal ion complexation and hence speciation was found to be highly variable within the Pieman River catchment. This presents major difficulties for environmental managers, as it is therefore not possible to make catchment-wide assumptions about the bioavailability of these metals. These results emphasise the importance of site-specific sampling protocols and speciation testing, ideally incorporating continuous, in situ monitoring.
|
14 |
Sustainability assessment within the residential building sector: a practical life cycle method applied in a developed and a developing countryOrtiz Rodríguez, Oscar Orlando 18 December 2009 (has links)
More than ever, the residential building sector is concerned with improving the social, economicand environmental indicators of sustainability. In order to overcome the increasing concern of today'sresource depletion, environmental considerations and to address sustainability indicators, a practicallife cycle method has been proposed to decision making integrating environmental and socioeconomicalaspects to analyse the impact of sustainability within the residential building sector usingtwo practical life cycle methods. One method is the Material and Energy Analysis (MEA) which issuggested as an appropriate tool to provide a systematic picture of the direct and physical flows of theuse of natural resources and the other is the environmental management tool of Life CycleAssessment (LCA) as a complement to evaluate environmental impacts throughout the life cycle of thesystem.Furthermore, the method provides sustainability information that facility an adequate decisionmaking towards sustainable development at macro and micro levels. Sustainability assessment atmacro level is determined by exogenous variables that can influence the development of a country.Meanwhile sustainable at the micro level is made within the limits of the whole building life cycle,starting from the construction, use (operation and maintenance) and finishing with the end-of-lifephase. To illustrate it, a case study has been carried out based on the application to two buildings, onelocated in Barcelona, Spain and one situated in Pamplona, Colombia. Then, the main objective of thisthesis is to propose a practical life cycle method including environmental and socio-economicalaspects to evaluate indicators that explicitly measure the residential building sector's impacts. Thisthesis has also provided initiatives for residential dwellings to reduce environmental impacts and assiststakeholders in improving customer patterns during the dwelling life cycle.The findings of this thesis state that the appropriate combination of building materials,improvement in behaviours and patterns of cultural consumption, and the application of governmentcodes would enhance decision-making in the residential building sector towards sustainability. Thedifference in consumption in Colombia and Spanish dwellings is not only due to the variation in resultsfor bio-climatic differences but also because of the consumption habits in each country. Theimportance of consumption habits of citizens and the need to decouple socio-economic developmentfrom energy consumption are sought for achieving sustainability from a life cycle perspective. There isa crucial necessity to provide satisfaction to basic needs and comfort requirements of population withreasonable and sustainable energy consumption.Therefore, there is no doubt that applying environmental managements tools as Life CycleAssessment (LCA) and Material and Energy Analysis (MEA) to the full building life cycle can be veryimportant for reducing environmental loads and thereby improving sustainability indicators. Then, anyimprovement in building sustainability is oriented generally to building materials, energy use and wastemanagement in all phases of the building life cycle, having always in mind that building has to bexxviiiaccessible from an economical and social part of view. The type of standard dwelling variessubstantially depending on the geographic location where it is built. Climate, technological, cultural,socio-economical differences clearly define the standard of a building in any context and in any region.This leads to important differences in the LCA results and it means that any extrapolation of existingEuropean LCA data to the case of a developing country would imply important errors. However, thefunction is always the same, to provide protection and housing for its habitants. / Hoy en día, el sector residencial busca mejorar los indicadores de sostenibilidad en los aspectossociales, económicos y ambientales. Con el fin de considerar la creciente preocupación delagotamiento de los recursos naturales y buscar reducir las emisiones adversa al medio ambiente, unmétodo practico basado en el ciclo de vida se ha propuesto para la evaluación socio-económica yevaluación del impacto ambiental en sector residencial utilizando dos métodos. El primero es elAnálisis de Materiales y de Energía (AME) que proporciona una visión sistemática de los flujosdirectos e indirectos de la utilización de los recursos naturales y el segundo método es el Análisis delCiclo de Vida (ACV) como complemento para evaluar los impactos ambientales en todo el ciclo devida del sistema.Adicionalmente, el método proporciona información de sostenibilidad permitiendo la adecuadatoma de decisiones hacia el desarrollo sostenible en los niveles macro y micro. Evaluación de laSostenibilidad en el nivel macro está determinado por variables exógenas que influyen en eldesarrollo de un país. Mientras tanto, sostenibilidad en el nivel micro hace referencia dentro de loslímites de todo el ciclo de vida de una vivienda, comenzando por la fase de construcción, uso(operación y mantenimiento) y terminando con la fase final. Para ilustrarlo, un caso de estudio ha sidollevado a cabo en la aplicación de dos edificios, uno situado en Barcelona, España y otro situado enPamplona, Colombia. Por consiguiente, el objetivo principal de esta tesis es proponer un método quetenga en cuenta los aspectos medio-ambientales y socio-económicos que tiendan a mejorar lasostenibilidad y que explícitamente midan los impactos del sector de residencial. Esta tesis también propone iniciativas de mejora en las viviendas residenciales que conlleven a reducir los impactos ambientales y asistir a los agentes involucrados del sector.Las conclusiones de esta tesis soportan que la combinación adecuada de materiales deconstrucción, el buen comportamiento en los patrones de consumo, y la aplicación de códigos y leyes mejoraran los aspectos sostenibles en el sector de la construcción. La diferencia en el consumo en las viviendas de Colombia y en las Españolas no sólo se debe a la variación de las diferencias bioclimáticas,sino también por los hábitos de consumo en cada país. Se puede observar la importancia de los hábitos de consumo de los ciudadanos y la necesidad de disociar el desarrollo socioeconómico del consumo de energía. Existe una necesidad fundamental de dar satisfacción a las necesidades básicas y requerimientos de confort de la población con un consumo energético razonable y sostenible.Por lo tanto, no hay duda de que la aplicación de herramientas medioambientales como el análisis del ciclo de vida (ACV) y análisis de materiales y energía (AME) es muy importante para minimizar el impacto ambiental y buscar mejorar los indicadores de sostenibilidad. Queda implícito entonces que cualquier mejora en la sostenibilidad está orientado generalmente a la selección apropiada de materiales de construcción, el uso eficiente de energía y la correcta gestión de residuos en todas las fases del ciclo de vida del edificio, teniendo siempre en cuenta que el edificio tiene que ser accesible desde una parte económica y social. El tipo de vivienda estándar varía sustancialmente dependiendo de la ubicación geográfica donde se construya. Aspectos como el clima, la tecnología, la cultura y las diferencias socio-económicas definen claramente el nivel de un edificio en cualquier contexto y en cualquier región. Esto da lugar a importantes diferencias en los resultados del ACV y significa que cualquier extrapolación de datos europeos existentes del ACV para el caso de un paísen desarrollo implicaría errores importantes. Sin embargo, la función es siempre la misma,proporcionar protección y vivienda para sus habitantes
|
15 |
Environmental impacts of cage aquaculture in the southeast arm of Lake Malawi: water and sediment quality and food web changesGondwe, Mangaliso John Gibson Symon 14 September 2009 (has links)
Lake Malawi is a great lake not only because of its size (30,800 km2) but also because of its unique fish diversity. The lake contains the highest number of freshwater fish species in the world. The fish species are hypothesized to have radiated within the lake, which is 1-2 million years old. The collapse of the capture fishery in Lake Malawi between the 1970s and 1990s led to the launch of cage culture of indigenous fish species in 2004 in the south east arm of the lake. While cage culture has been practiced for many years in temperate lakes and seas, the fish farm in Lake Malawi is the first in the African Great Lakes and, therefore, not much information currently exists that is relevant to the impact of cage culture on such a large, species-rich tropical lake. Consequently, a study was done between January and December, 2007, at the fish farm in Lake Malawi to determine potential impacts of cage wastes on the environment. The study found that, just like in temperate systems where 70-87% of C, N and P added through feed get dispersed into the environment, discharges from fish cages in Lake Malawi were between 71-88% of the nutrients added through feed. The discharges were proportional to the amount of feed added so that as production and feed supply increase over time, more cage wastes would be generated and released into the environment. The discharges were exacerbated by poor stocking and feeding regimes. Production periods were longer (mean of 376±42 days) than if recommended stocking and feeding rates were followed. Feed quality may also have affected production performance and waste generation in the cages, but was not studied. The cage wastes were incorporated into the food web and support the wild fishes in the vicinity of the fish farm. Impacts of the cage wastes on the water column and sediments in the vicinity of the cages were minimal during the study period, probably because of rapid and efficient dispersion of the wastes by strong water currents, that averaged 9.3 cm s-1, through the cages and high consumption of the cage wastes by large numbers of wild fishes which aggregated around the cages. The wild fishes also helped to disperse the cage wastes over a larger area through consumption, translocation and defecation. However, as production increases, the amount of cage wastes generated may overwhelm mitigation by dispersion by water currents and consumption by wild fishes, particularly if many cages are deployed close together and interfere with current flows. Based on my observations, a fish farm that produces 15,000 tonnes fish/yr in Lake Malawi would generate 1249, 113 and 21 megamoles/yr of C, N and P, respectively, that are comparable or higher than DOC, TDN and TDP loadings observed in the most disturbed large river systems draining into Lake Malawi. The impacts of these river systems in Lake Malawi have been well documented, particularly around river mouths and in the more densely populated and shallower southern portion of the lake, where algal communities and their sedimentation rates have begun to change. Cage culture discharges may accelerate these changes.
|
16 |
Using GIS for Analysis of the Runway Extension of Margaret Ekpo International Airport, Calabar, NigeriaUche, Eugene, Oparah, Charles January 2012 (has links)
This study investigates the proposed extension of the existing runway of Margaret Ekpo International Airport, Calabar, Cross River State, Nigeria. The process involves the application of Geographic Information System (GIS) and several geospatial techniques for analysis and result presentation. The aim of the study was achieved with the following resources: satellite imagery downloaded from the Landsat webpage and processed to generate a land use map of the study area; a Digital Elevation Model (DEM) covering the study area which was downloaded from the Consortium for Spatial Information’s (CSI) webpage and observed ground spot heights along the straight path of the proposed runway extension covering a total length of 2.5km and 200m wide. These datasets were modified, processed and assigned the same coordinate system in order to make them conformal for analysis. A GIS was created with the foregoing resources in conjunction with other geospatial applications such as ERDAS Imagine and Surfer 8 to carry out the analysis. The analysis covered the environmental impacts of the proposed project, its effects on already existing human settlements and the huge cost implications based on certain conditions like the mandatory straight path which has to be maintained as an extension of the existing runway. Other factors considered are; the land use of the extension area, the economic benefits of the project, the accessibility of the area, noise pollution as well as the safety and security issues involved. A summary of the result of our analysis shows features such as residential settlements, roads, swampy areas, valleys and areas of high elevation which will act as obstructions along the proposed runway path. Also, the total surface area of the proposed runway and the volume of earth material required were calculated. The results achieved from this study shows that GIS and other geospatial tools are indispensable resources in complex planning processes such as facility maintenance and management.
|
17 |
Environmental impacts of cage aquaculture in the southeast arm of Lake Malawi: water and sediment quality and food web changesGondwe, Mangaliso John Gibson Symon 14 September 2009 (has links)
Lake Malawi is a great lake not only because of its size (30,800 km2) but also because of its unique fish diversity. The lake contains the highest number of freshwater fish species in the world. The fish species are hypothesized to have radiated within the lake, which is 1-2 million years old. The collapse of the capture fishery in Lake Malawi between the 1970s and 1990s led to the launch of cage culture of indigenous fish species in 2004 in the south east arm of the lake. While cage culture has been practiced for many years in temperate lakes and seas, the fish farm in Lake Malawi is the first in the African Great Lakes and, therefore, not much information currently exists that is relevant to the impact of cage culture on such a large, species-rich tropical lake. Consequently, a study was done between January and December, 2007, at the fish farm in Lake Malawi to determine potential impacts of cage wastes on the environment. The study found that, just like in temperate systems where 70-87% of C, N and P added through feed get dispersed into the environment, discharges from fish cages in Lake Malawi were between 71-88% of the nutrients added through feed. The discharges were proportional to the amount of feed added so that as production and feed supply increase over time, more cage wastes would be generated and released into the environment. The discharges were exacerbated by poor stocking and feeding regimes. Production periods were longer (mean of 376±42 days) than if recommended stocking and feeding rates were followed. Feed quality may also have affected production performance and waste generation in the cages, but was not studied. The cage wastes were incorporated into the food web and support the wild fishes in the vicinity of the fish farm. Impacts of the cage wastes on the water column and sediments in the vicinity of the cages were minimal during the study period, probably because of rapid and efficient dispersion of the wastes by strong water currents, that averaged 9.3 cm s-1, through the cages and high consumption of the cage wastes by large numbers of wild fishes which aggregated around the cages. The wild fishes also helped to disperse the cage wastes over a larger area through consumption, translocation and defecation. However, as production increases, the amount of cage wastes generated may overwhelm mitigation by dispersion by water currents and consumption by wild fishes, particularly if many cages are deployed close together and interfere with current flows. Based on my observations, a fish farm that produces 15,000 tonnes fish/yr in Lake Malawi would generate 1249, 113 and 21 megamoles/yr of C, N and P, respectively, that are comparable or higher than DOC, TDN and TDP loadings observed in the most disturbed large river systems draining into Lake Malawi. The impacts of these river systems in Lake Malawi have been well documented, particularly around river mouths and in the more densely populated and shallower southern portion of the lake, where algal communities and their sedimentation rates have begun to change. Cage culture discharges may accelerate these changes.
|
18 |
Environmental impacts of the digital economy: The case of Austin, Texas, 1990-2008Tu, Wei 29 August 2005 (has links)
This dissertation investigates the dynamic economic structure transformation and its corresponding environmental consequences at the Austin-San Marcos Metropolitan Statistical Area (Austin MSA) from 1990 to 2008. Input-output (IO) analysis is the major methodology and environmental problems are defined as emissions of industrial point air pollutants. Both three-and seven-segment IO models of Austin MSA for the years of 1990, 1994, and 1999 are constructed. Direct and total pollution coefficients of six major pollutants are calculated, hypothe tical extraction measurement and structural decomposition analysis are implemented, and the quantity and pattern of pollutant emissions are simulated based on four major assumed development scenarios from 2000 to 2008.
This study finds: 1) the digital economy has emerged in the Austin MSA during the 1990s, 2) the manufacturing process of Austin MSA tended to be more environmentally friendly, which supports the hypothesis of dematerialization and decarbonization, 3) consumption-driven and non-production segments related environmental problems becomes more significant in the emerging digital economy.
This study predicts that industrial point air pollutant emissions will grow moderately from 2000 to 2008, assuming that the direct pollutant coefficients will change at the average rates of the 1990s and the final demand will grow at the half rates of the 1990s?? average. Pollution contribution from production segment will generally decrease and contribution from other segments such as ICT and Information will increase, however, emission contributions of the segments will vary in terms of pollutants as well as development scenarios.
This study argues that the shift of the source and nature of environmental threats of in the digital economy mandates parallel reform of the current environmental policy. A new generation of policy should be cooperative rather than confrontational, integrated rather than fragmented, flexible rather than rigid. It should also facilitate innovative management initiatives to achieve sustainability. More fundamentally, it is expected to deal with environmental impacts of intangible information flows (bits) which are possibly more essential than flows of tangible goods and services (atoms) in the context of the digital economy and the information age.
|
19 |
Assessing non-point source pollution in agricultural regions of the upper St. John River basin using the slimy sculpin (Cottus cognatus)Gray, Michelle Anya January 2003 (has links)
The overall objective of this research project was to assess whether fish populations in areas of potato cultivation responded to changes in environmental conditions. An effects-based assessment was conducted in the ‘potato belt’ of northwestern New Brunswick in the Little River catchment. From 1999-2001, the health and performance of slimy sculpin (Cottus cognatus) was monitored in agricultural and forested sections of the river. In the fall of 1999 and 2000, agricultural sites had fewer young-of-the-year (YOY) sculpin than the forested region. Adult sculpin were larger in the agricultural region, but had significantly smaller gonads, and female sculpin had smaller livers, and fewer and smaller eggs than the forested region. By the fall of 2001, only female gonad size showed a difference from the forested region. These results were used to design a follow-up study designed to investigate the relative importance of environmental factors influencing sculpin responses. <br><br>
The second study investigated the relative influence of temperature and sediment deposition on slimy sculpin populations across 20 sites on 19 streams in forested and agricultural catchments in northwestern New Brunswick. YOY sculpin were present at all forested sites, but only at 2 of 11 agricultural sites. There were no relationships between body size or density and sediment deposition in either the agricultural or forested regions, but sculpin density decreased and median YOY size increased with increasing temperatures. The variability in density of YOY sculpin at agricultural sites suggested that additional factors beyond temperature might be contributing to responses.
<br><br>
A secondary overall objective was to evaluate the slimy sculpin as a sentinel and indicator of site-specific conditions. Stable isotopes of muscle tissues showed little variability in isotopic signatures, and significant differences between adjacent sites. Passive integrated transponder (PIT) tags implanted in 112 adult sculpin showed that 75% of sculpin captured over 10 months moved less than 30m. Both isotopes and PIT tags suggested high spatial and temporal residency of slimy sculpin.
<br><br>
This PhD project showed biological impacts on sculpin populations residing in streams influenced by non-point source agricultural stressors, and provided support for the ability of the slimy sculpin to reflect local environmental conditions.
|
20 |
Mudanças no uso da terra no alto curso da bacia do Ribeirão dos Ranchos – Adamantina/SP e impactos sobre os cursos d´água / Land use changes in the high course of the Ribeirão dos Ranchos basin – Adamantina/SP and impacts on water coursesKohori, Carolina Bugalho [UNESP] 28 November 2017 (has links)
Submitted by CAROLINA BUGALHO KOHORI null (cbkohori@gmail.com) on 2018-01-09T16:22:59Z
No. of bitstreams: 1
Dissertação_Carolina Kohori.pdf: 7577720 bytes, checksum: 9922fcf0e1720d723287605b348853f3 (MD5) / Approved for entry into archive by Claudia Adriana Spindola null (claudia@fct.unesp.br) on 2018-01-09T18:06:26Z (GMT) No. of bitstreams: 1
kohori_cb_me_prud.pdf: 7577720 bytes, checksum: 9922fcf0e1720d723287605b348853f3 (MD5) / Made available in DSpace on 2018-01-09T18:06:26Z (GMT). No. of bitstreams: 1
kohori_cb_me_prud.pdf: 7577720 bytes, checksum: 9922fcf0e1720d723287605b348853f3 (MD5)
Previous issue date: 2017-11-28 / A Nova Alta Paulista foi uma das últimas regiões a serem atravessadas pela ferrovia e ocupadas pela frente cafeeira, tendo suas formações vegetais naturais quase que totalmente suprimidas em detrimento da expansão da área urbana e de culturas agropecuárias. As sedes dos municípios foram construídas no espigão-divisor de águas dos rios Aguapeí e Peixe, ocupando diversas nascentes de córregos. Diante dessa realidade, diversos impactos da falta de planejamento, manejo e gestão do solo e da água são observados, sendo necessários estudos a fim de entender a dinâmica que ocorreu na região. Para tanto, propôs-se o estudo do alto curso da bacia do Ribeirão dos Ranchos, formado pelas bacias dos córregos Taipus, Tocantins e Ranchos, localizada no município de Adamantina, integrante da Nova Alta Paulista. O objetivo do trabalho foi analisar as mudanças ocorridas no uso da terra entre os anos de 1971 e 2016 e seus respectivos impactos ambientais sobre essa área, utilizando técnicas de geoprocessamento. Após a realização do mapeamento, foram processados e gerados mapas de ganho, persistência e perda de área para as classes de uso da terra. Através das análises realizadas observouse que a área de estudo tem riscos de ocorrência de inundações e a ocupação urbana sobre as áreas de nascentes intensificam esses problemas. Com relação às mudanças no uso da terra, houve significativas mudanças, onde as lavouras temporária e permanente cederam espaço para a pastagem cultivada para criação de gado. Os principais problemas ambientais observados na área rural foram pastagens degradadas, ausência de mata ciliar, solos erodidos, assoreamento e contaminação dos recursos hídricos. Notou-se, ainda, pequeno avanço relacionado à recomposição das áreas de preservação permanente que, no entanto, não devem ser desprezadas. Espera-se que o presente trabalho possa contribuir para estudos mais aprofundados na região e para a tomada de decisões que visem o planejamento de ocupação do uso da terra em áreas urbana e rural, bem como a recuperação das APPs (Áreas de Preservação Permanente) e, em longo prazo, dos córregos. / The Nova Alta Paulista was one of the last regions to be crossed by the railroad and occupied by the coffee crop, having its natural landscap almost totally suppressed to by the expansion of the urban area and agricultural crops. The municipalities were built inside of the Aguapeí and Peixe rivers watershed , occupying several streams springs. Therefore, several impacts due to lack of planning, soil and water management are observed, and studies are necessaries to understand the dynamics that took place in the region. Thus, a has been developed on the high course of the Ribeirão dos Ranchos basin, formed by the Taipus, Tocantins and Ranchos basins, located in the municipality of Adamantina, a member of Nova Alta Paulista. The objective of this work was to analyze the changes in land use between the years 1971 and 2016 and their respective environmental impacts, using geoprocessing techniques. After the mapping, maps of gain, persistence and loss of area for land use classes were processed and generated. Through the analyzes conducted , it has been observed that the study area has flood risks occurrence and urban occupation on the river source’s areas intensifies these problems. Regarding changes in land use, there were significant changes, where temporary and permanent crops gave way to pasture grown for livestock. The main environmental problems observed in the rural area were degraded pastures, absence of riparian forest, eroded soils, sedimentation and water resources contamination. Still, there was a small advance related to the restoration of permanent preservation areas, which should not be neglected. It is expected that the present work shall contribute to further studies in the region, to the decision making aiming land use management in urban and rural areas, as well as the recovery of PPAs (Permanent Preservation Areas) and, in the long term, streams.
|
Page generated in 0.1291 seconds