934 resultados para Waste lands


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Forest connectivity restoration is a major goal in natural resource planning. Given the high amount of abandoned cultivated lands, setting efficient methods for the reforestation of agricultural lands offers a good opportunity to face this issue. However, reforestations must be carefully planned, which poses two main challenges. In first place, to determine those agricultural lands that, once reforested, would meet more effectively the planning goals. As a further step, in order to grant the success of the activity, it is fairly advisable to select those tree species that are more adapted to each particular environment. Here we intend to give response to both requirements by proposing a sequential and integrated methodology that has been implemented in two Spanish forest districts, which are formed by several landscape types that were previously defined and characterized. Using the software Conefor Sensinode, a powerful tool for quantifying habitat availability that is based on graph theory concepts, we determined the landscapes where forest planning should have connectivity as a major concern and, afterwards, we detected the agricultural patches that would contribute most to enhance connectivity if they were reforested. The subsequent reforestation species assessment was performed within these priority patches. Using penalized logistic regressions we fitted ecological niche models for the Spanish native tree species. The models were trained with species distribution data from the Spanish Forest Map and used climatic and lithological variables as predictors. Model predictions were used to build ordered lists of suitable species for each priority patch. The lists include dominant and non dominant tree species and allow adding biodiversity goals to the reforestation planning. The result of this combined methodology is a map of agricultural patches that would contribute most to uphold forest connectivity if they were reforested and a list of suitable tree species for each patch ordered by occurrence probability. Therefore the proposed methodology may be useful for suitable and efficient forest planning and landscape designing.

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Processes of founding and expanding cities in coastal areas have undergone great changes over time driven by environmental conditions. Coastal settlements looked for places above flood levels and away from swamps and other wetlands whenever possible. As populations grew, cities were extending trying to avoid low and wet lands. No city has been able to limit its growth. The risk of flooding can never be eliminated, but only reduced to the extent possible. Flooding of coastal areas is today dramatically attributed to eustasic sea level rise caused by global climate change. This can be inaccurate. Current climate change is generating an average sea level upward trend, but other regional and local factors result in this trend being accentuated in some places or attenuated, and even reversed, in others. Then, the intensity and frequency of coastal flooding around the planet, although not so much as a unique result of this general eustasic elevation, but rather of the superposition of marine and crustal dynamic elements, the former also climate-related, which give rise to a temporary raising in average sea level in the short term. Since the Little Ice Age the planet has been suffering a global warming change leading to sea level rise. The idea of being too obeying to anthropogenic factors may be attributed to Arrhenius (1896), though it is of much later highlight after the sixties of the last century. Never before, the human factor had been able of such an influence on climate. However, other types of changes in sea levels became apparent, resulting from vertical movements of the crust, modifications of sea basins due to continents fracturing, drifting and coming together, or to different types of climate patterns. Coastal zones are then doubly susceptible to floods. Precipitation immediately triggers pluvial flooding. If it continues upland or when snow and glaciers melt eventually fluvial flooding can occur. The urban development presence represents modifying factors. Additional interference is caused by river and waste water drainage systems. Climate also influences sea levels in coastal areas, where tides as well as the structure and dynamic of the geoid and its crust come into play. From the sea, waters can flood and break or push back berms and other coastline borders. The sea level, controlling the mouth of the main channel of the basin's drainage system, is ultimately what governs flood levels. A temporary rise in sea level acts as a dam at the mouth. Even in absence of that global change, so, floods are likely going to increase in many urban coastal areas. Some kind of innovative methodologies and practices should be needed to get more flood resilience cities

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Drought spells can impose severe impacts in most vulnerable farms. It is well known that uninsured exposure exacerbates income inequality in farming systems. However, high administrative costs of traditional insurance hinder small farmers? access to risk management tools. The existence of moral hazard and systemic risk prevents the implementation of traditional insurance programs to address drought risk in rural areas. Innovative technologies like satellite images are being used to derive vegetation index which are highly correlated with drought impacts. The implementation of this technology in agricultural insurance may help to overcome some of the limitations of traditional insurance. However, basis risk has been identified as one of the main problems that hinder the acceptance of index insurance. In this paper we focus on the analyses of basis risk under different contract options in the grazing lands of the Araucanía region. A vegetation index database is used to develop an actuarial insurance model and estimate risk premiums for moderate and severe drought coverage. Risk premium sharply increases with risk coverage. In contrast with previous findings in the literature, our results are not conclusive and show that lowering the coverage level does not necessarily imply a reduction in basis risk. Further analyses of the relation between contract design and basis risk is a promising area of research that may render an important social utility for most vulnerable farming systems.

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The intense activity in the construction sector during the last decade has generated huge volumes of construction and demolition (C&D) waste. In average, Europe has generated around 890 million tonnes of construction and demolition waste per year. Although now the activity has entered in a phase of decline, due to the change of the economic cycle, we don’t have to forget all the problems caused by such waste, or rather, by their management which is still far from achieving the overall target of 70% for C&D waste --excludes soil and stones not containing dangerous substances-- should be recycled in the EU Countries by 2020 (Waste Framework Directive). But in fact, the reality is that only 50% of the C&D waste generated in EU is recycled and 40% of it corresponds to the recycling of soil and stones not containing dangerous substances. Aware of this situation, the European Countries are implementing national policies as well as different measures to prevent the waste that can be avoidable and to promote measures to increase recycling and recovering. In this aspect, this article gives an overview of the amount of C&D waste generated in European countries, as well as the amount of this waste that is being recycled and the different measures that European countries have applied to solve this situation.

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The construction industry, one of the most important ones in the development of a country, generates unavoidable impacts on the environment. The social demand towards greater respect for the environment is a high and general outcry. Therefore, the construction industry needs to reduce the impact it produces. Proper waste management is not enough; we must take a further step in environmental management, where new measures need to be introduced for the prevention at source, such as good practices to promote recycling. Following the amendment of the legal frame applicable to Construction and Demolition Waste (C&D waste), important developments have been incorporated in European and International laws, aiming to promote the culture of reusing and recycling. This change of mindset, that is progressively taking place in society, is allowing for the consideration of C&D waste no longer as an unusable waste, but as a reusable material. The main objective of the work presented in this paper is to enhance C&D waste management systems through the development of preventive measures during the construction process. These measures concern all the agents intervening in the construction process as only the personal implication of all of them can ensure an efficient management of the C&D waste generated. Finally, a model based on preventive measures achieves organizational cohesion between the different stages of the construction process, as well as promoting the conservation of raw materials through the use and waste minimization. All of these in order to achieve a C&D waste management system, whose primary goal is zero waste generation

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Agricultural wastes are a source of renewable raw materials (RRM), with structures that can be tailored for the use envisaged. Here, they have proved to be good replacement candidates for use as biomaterials for the growth of osteoblasts in bone replacement therapies. Their preparation is more cost effective than that of materials presently in use with the added bonus of converting a low-cost waste into a value-added product. Due to their origin these solids are ecomaterials. In this study, several techniques, including X-ray diffraction (XRD), chemical analysis, mercury intrusion porosimetry (MIP), scanning electron microscopy (SEM), and bioassays, were used to compare the biocompatibility and cell growth of scaffolds produced from beer bagasse, a waste material from beer production, with a control sample used in bone and dental regenerative processes.

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Waste produced during the service life of automobiles has received much less attention than end-of-life vehicles themselves. In this paper, we deal with the set up of a reverse logistics system for the collection and treatment of use-phase residues. First, the type of waste arising during vehicles? service life is characterized. Data were collected in collaboration with SIGRAUTO, the product stewardship organization in charge of vehicles? recovery in Spain. Next, three organizational models are proposed. The three alternatives are benchmarked and assessed from a double organizational and operational perspective for the particular case of the Madrid region in Spain

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Aquaponics is the science of integrating intensive fish aquaculture with plant production in recirculating water systems. Although ion waste production by fish cannot satisfy all plant requirements, less is known about the relationship between total feed provided for fish and the production of milliequivalents (mEq) of different macronutrients for plants, especially for nutrient flow hydroponics used for strawberry production in Spain. That knowledge is essential to consider the amount of macronutrients available in aquaculture systems so that farmers can estimate how much nutrient needs to be supplemented in the waste water from fish, to produce viable plant growth. In the present experiment, tilapia (Oreochromis niloticus L.) were grown in a small-scale recirculating system at two different densities while growth and feed consumption were noted every week for five weeks. At the same time points, water samples were taken to measure pH, EC25, HCO3 – , Cl – , NH4 + , NO2 – , NO3 – , H2PO4 – , SO4 2– , Na + , K+ , Ca 2+ and Mg 2+ build up. The total increase in mEq of each ion per kg of feed provided to the fish was highest for NO3 - , followed, in decreasing order, by Ca 2+ , H2PO4 – , K+ , Mg 2+ and SO4 2– . The total amount of feed required per mEq ranged from 1.61- 13.1 kg for the four most abundant ions (NO3 – , Ca 2+ , H2PO4 – and K+ ) at a density of 2 kg fish m–3 , suggesting that it would be rather easy to maintain small populations of fish to reduce the cost of hydroponic solution supplementation for strawberries.

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The United Nations Climate Change Conference, Durban 2011, delivered a breakthrough on the international community's response to climate change. In the second largest meeting of its kind, the negotiations advanced, in a balanced fashion, the implementation of the Convention and the Kyoto Protocol, the Bali Action Plan, and the Cancun Agreements. The outcomes included a decision by Parties to adopt a universal legal agreement on climate change as soon as possible, and no later than 2015. One of the decisions adopted by COP 17 and CMP 7 regard to the land use, land-use change and forestry, and invites the Intergovernmental Panel on Climate Change to review and, if necessary, update supplementary methodologies for estimating anthropogenic greenhouse gas emissions by sources and removals by sinks resulting from land use, land-use change and forestry activities under Article 3, paragraphs 3 and 4, of the Kyoto Protocol. Land degradation is a human-induced or natural process which negatively affects the productivity of land within an ecosystem. The direct causes of land degradation are geographically specific. Climate change, including changes in short-term variation, as well as long-term gradual changes in temperature and precipitation, is expected to be an additional stress on rates of land degradation. Book Topics: • Introduction to Climate Change and Land Degradation • Change Mitigation • Climate Change and Waste Land Restoration • Water Management and Planning • Erosion and Hydrological Restoration • Forest Fire Land Restoration • Polluted Soils Restoration • Combating Climate Change by Restoration of Degraded Land • Research Matters – Climate Change Governance • Advanced Statistics Climate Change and Restoration of Degraded Land is of interests to academics, engineers, consultans, designers and professionals involved in restoration of degraded lands projects.

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The main objective of this research is to study the feasibility of recycling fibres from construction and demolition waste (C&DW) as an alternative material to chopped glass fibres which are used today as reinforcing elements in the prefabricated plaster. To do this, sets of samples are made with rockwool and different percentages of combinations between water / plaster. These series are repeated by changing the additive E glass fibre length of 25mm to make a comparative analysis with respect to the series infused with rockwool.

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The use of mineral wool is becoming more widespread due to increased acoustic and thermal demands of Spanish Technical Building Code. This increase affects both in rehabilitation and new construction projects. Therefore, waste generation of this type of insulating material is having more importance. The main objective of this research is to study the possibility of recycling fiber obtained from mineral wool of the C&DW as an alternative material to chopped glass fibers that are currently used as reinforcing elements in the prefabricated plaster. To achieve this objective, series are made of plaster E-35 additived with rock wool residue and glass wool residue at different rates of addition. These series are repeated by changing the additive by E fiberglass (length of 25mm) to make a comparative analysis with respect to the series additived with mineral wool waste. All the series are subjected to the test to determine Shore C surface hardness and mechanical testing to determine the compressive and flexural strength. From the results it can be concluded that: with rock wool residue, increases Shore C hardness up to 15% with respect to the glass fiber and 9% with respect to the glass wool, with a percentage of addition 2%. With rock wool residue, weight is decreased by 5% with respect to the glass fiber and 4% with respect to the glass wool waste, with an addition percentage of 4%. For an addition rate of 4%, results in the flexural strength test with fiberglass are 85% higher than those obtained with glass wool residue. However, for a percentage of 1% addition, the results obtained with glass wool residue are 35% higher than those obtained with fiberglass. For an addition rate of 3% results in the compressive strength test with fiberglass are 54% lower than those obtained with rock wool waste and 70% lower than those obtained with glass wool waste. Comparing the two mineral wools, it can be concluded that up to 3% of the addition, the glass wool series results obtained are 10% higher than those additived with rock wool. However, higher percentages of addition show that the results obtained with rock wool are 35% higher than those obtained with glass wool. The general conclusion is that the series additived with mineral wool from C&DW show better results in tests than the ones used nowadays as plaster reinforcement.

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The difficulty of dealing with construction and demolition waste (CDW) on construction sites is not new and continues to be a significant environmental problem. Currently the CDW collection system in Spain is done in a decentralized manner by each sub-contracted company, being necessary to implement effective waste management measures ensuring a correct management and minimization. During the last years several measures have been launched in order to improve and encourage the reuse and recycling of CDW. A widespread solution for CDW recovery is using them as a landscaping aggregate or for road bases and sub-bases. However, measures encouraging onsite prevention still need to be enhanced. This paper studies the major work stage generating CDW and analyses the categories of CDW produced during its execution. For this, several real building sites have been analysed in order to quantify the estimation of CDW generated. Results of this study show that a significant contributor to the CDW generation on building construction sites in Spain are the masonry works. Finally, a Best Practices Manual (BPM) is proposed containing several strategies on masonry works aimed not only at CDW prevention, but also at improving their management and minimization. The use of this BPM together with the Study and Plan of CDW management --required by law--, promotes the environmental management of the company, favouring the cohesion of the construction process organization at all stages giving rise to establishing responsibilities in the field of waste and providing a greater control over the process. Keywords: construction and demolition waste, management, masonry works, good practice measures, prevention.

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New European directives have proposed the direct application of compost and digestate produced from municipal solid wastes as organic matter sources in agricultural soils. Therefore information about phosphorus leaching from these residues when they are applied to the soil is increasingly mportant. Leaching experiments were conducted to determine the P mobility in compost and digestate mixtures, supplying equivalent amounts to 100 kg P ha?1 to three different types of soils. The tests were performed in accordance with CEN/TS 14405:2004 analyzing the maximum dissolved reactive P and the kinetic rate in the leachate. P biowaste fractionation indicated that digestate has a higher level of available P than compost has. In contrast, P losses in leaching experiments with soil-compost mixtureswere higher than in soil-digestate mixtures. For bothwastes, therewas no correlation between disolved reactive P lost and the water soluble P.The interaction between soil and waste, the long experimentation time, and the volume of leachate obtained caused the waste?s wettability to become an influential parameter in P leaching behavior. The overall conclusion is that kinetic data analysis provides valuable information concerning the sorption mechanism that can be used for predicting the large-scale behavior of soil systems.