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971.
Based on the national database of 28,104 water rights (concessions) granted in Colombia, this paper presents an analysis of how the principles of equity and sustainability are reflected in water allocation. Concessions appear to be an exclusionary mechanism since only a minority of small water users have concessions and the distribution of water volumes among those who have them is extremely inequitable. The 2009 Gini coefficient calculated for water concessions granted for agriculture was 0.90 compared with the rural land Gini of 0.88 (both indicators grouping holdings under the same entity). More than half of the Colombian departments have a higher Gini coefficient for water than for land, suggesting that water rights are at least as unequally distributed as land, in one of the most inequitable countries in Latin America. Water allocated to domestic, agriculture and hydropower use indicates a lack of consistency of water allocation criteria across regions. The volumetric and administrative attributes of water allocation in Colombia do not account for environmental flows or the concerns of marginalised groups of society that have limited access to the mechanism. Water allocation as a technical task, with limited transparency and secluded from public scrutiny, does not contribute to the solution of increasing water-related conflicts.  相似文献   
972.
In recent years, animal welfare has become an important element of sustainable production that has evolved along with the transformation of animal production systems. Consumer attitudes towards farm animal welfare are changing around the world, especially at emerging markets of Asia, Africa and Latin America. Survey-based research on consumer attitudes towards farm animal welfare has increased. However, the geographical coverage of studies on consumer attitudes and perceptions about farm animal welfare has mostly been limited to Europe, and North America. Until now, Latin American consumers’ attitudes towards animal welfare have not been well studied. Despite the fact that Mexico, Chile and Brazil belong to the same region (according to international organizations), there are marked differences between these countries in terms of their economical and geographical characteristics among other factors. Those differences potentially have an impact on consumer attitudes towards animal welfare and livestock production systems in general. Given the evidence from the literature review, it seems advisable that Latin American producers and food industry who engage in animal welfare-enhancing practices should clearly label their products with information on the type of husbandry system to reach those consumers who want to make an informed choice. Therefore, there are some aspects that need to be studied and cannot be worked separately in order to promote and understand consumer attitudes towards dairy and beef systems, such as geography, economic development, and politics.  相似文献   
973.
This study aimed to develop and characterize biodegradable films containing mucilage, chitosan and polyvinyl alcohol (PVA) in different concentrations. The films were prepared by casting on glass plates using glycerol as plasticizer. Mechanical properties, water vapor and oxygen barrier, as well as the interaction with water, were measured. The compatibility of the film-forming components and the uniformity of the films were determined by zeta potential and SEM, respectively. The glycerol and mucilage allowed obtaining more hydrophilic films. The barrier properties of the films made from 100 % chitosan were similar to composed films containing PVA up to 40 %. The results of this study suggest that the interaction between chitosan and mucilage could increase water vapor permeability. The films prepared from either 100 % chitosan or PVA showed a more hydrophobic behavior as compared to the composed films. The films were homogenous since no boundary or separation of components was observed, indicating a good compatibility of the components in the films.  相似文献   
974.

This paper investigates the dimensions of sustainable behavior, with a particular focus on the aspects of self-care, caring for others, and caring for the environment. Its aim was to test the assumption that sustainable behavior not only encompasses pro-social and pro-environmental actions, as the current research acknowledges, but also behaviors that are directed toward self-preservation and care. A subscale of self-care specifically developed for this research was added to a series of previously validated instruments assessing altruistic, equitable, pro-ecological, and frugal behaviors to examine the personal, social, and physical environmental aspects of sustainable behavior. Responses from a sample of 290 participants confirmed the three-dimensional structure of sustainable behavior. Results suggest sustainability, understood as a chain of interdependences between the individual, society, and nature, begins with self-care and continues with caring for others, and with caring for the biosphere, which, in turn, affords for a more sustainable environment for the individual.

  相似文献   
975.

Social acceptance is fundamental, and directly affects the installation of wind farms. In this paper, the factors that have had the greatest influence on the development of wind energy in the Itsmo region of Tehuantepec, Mexico are identified. The data were collected face to face through a semi-structured questionnaire of 31 people: owners, municipal authorities, opposition groups, and academic members. The results of the interview highlight the social impact, the lack of application, and concerning ILO Convention 169, the abuse of community rights. As a result, people interviewed perceive that the environmental impact of the installation, and operation of wind farms has been ambivalent: positive due to the intrinsic benefits that wind energy generates compared to other energy sources, and negative in terms of affectation by the noise, and the landscape. However, the income received by the owners of land in which wind facilities are located is lower compared to other parts of the world. In general, the facts show a disintegration between the authorities (federal, state, and municipal), universities are isolated from wind projects, communities are not consulted in projects, and large companies are the main beneficiaries.

  相似文献   
976.
Environment, Development and Sustainability - Even though ecosystem services have a significant contribution to human well-being, their value is not always recognized. Despite difficulties, the...  相似文献   
977.
The present study evaluated the effect of culture conditions and phytopathogenic strain co-culture on the production of antimicrobial metabolites and antifungal activity of Penicillium chrysogenum R1, which PCR identified. Antimicrobial activity was determined using the Hunter-Hunter experimental design with three factors (pH, incubation temperature, and inoculum, at two levels each). The antifungal metabolites, β 1-3 glucanase and chitinase, produced in the presence of live and inactivated Fusarium oxysporum Fsox C11 biomass, were evaluated using HPLC-MS and GC-MS. Results showed that P. chrysogenum inhibited the growth of five phytopathogenic fungal strains, and the most significant inhibition was observed for F. oxysporum Fsox C11. The best conditions to achieve the highest antifungal activity of the cell-free extract were pH 7, 28°C, 1 × 106 spores/mL, and 144 h of fermentation, observing 86% inhibition of F. oxysporum Fsox C11 growth. Production of antifungal metabolites such as 1,4-benzoquinone imine, viridicatic acid, phenol-5-methyl-2-(1-methyl ethyl), and hydrolytic enzymes β 1-3 glucanase and chitinase was detected. The results define the perspective in designing new processes and products for biocontrol phytopathogens.  相似文献   
978.
Light duty gasoline vehicles account for most of CO hydrocarbons and NOx emissions at the Metropolitan Area of Mexico City (MAMC). In order to ameliorate air pollution from the beginning of 2001, Tier 1 emission standards became mandatory for all new model year sold in the country. Car manufacturers in Mexico do not guarantee the performance of their exhaust emissions systems for a given mileage. The purpose of this study was to assess whether the Tier 1 vehicles will stand the certification values for at least 162000 km with the regular fuel available at the MAMC. Mileage accumulation and deterioration show that certified carbon monoxide emissions will stand for the useful life of the vehicles but in the case of non-methane hydrocarbons will be shorter by 40%, and nitrogen oxides emissions above the standard will be reached at one third of the accumulated kilometers. The effect of gasoline sulfur content, on the current in use Tier 1 vehicles of the MAMC and the impact on the emissions inventory in year 2010 showed that 31000 extra tons of NOx could be added to the inventory caused by the failure of the vehicles to control this pollutant at the useful life of vehicles.  相似文献   
979.
A multivariate approach was used to test the value of intertidal communities as a bioindicator of environmental conditions at Algeciras Bay, southern Spain. The study area is located in the Strait of Gibraltar and it is subjected to a variety of anthropic impacts. Eight localities (5 inside and 3 outside the bay) were selected, and four transects were undertaken in each locality to characterise the fauna and flora. The spatial distribution of the intertidal species reflected the physico-chemical conditions of Algeciras Bay. The stations located outside the bay, characterised by high hydrodynamism and dissolved oxygen and low sedimentation and turbidity, had a higher diversity and species richness than the inner stations. According to the BIO-ENV procedure and CCA, water turbidity was the factor which best correlated with the intertidal assemblages. SIMPER showed that the molluscs Chtamalus stellatus, Mytilus cf edulis, Littorina neritoides and Balanus perforatus, and the algae Gelidium pusillum, Corallina elongata, Asparagopsis armata, Colpomenia sinuosa and Fucus spiralis were the species that most contributed to the dissimilarity between internal and external sites. The present study, based on the spatial distribution of intertidal taxa, yielded similar results to those previously obtained in the area with costly physico-chemical analysis based on complex matrices of subtidal epifaunal communities. Consequently, the intertidal sampling method proposed in this study is presented here as a quick, effective alternative strategy, and can be useful in environmental monitoring programs, since these communities are easily accessible and amenable to sample, and the sessile nature of the majority of the species makes future, long-term monitoring relatively simple.  相似文献   
980.
This study examines the effects of visitors on vegetation of natural semi-arid areas of Mediterranean basin using controlled experimental trampling. Impacts were assessed on days 1, 5, 15 and 30 examining presence of plant species, their cover and height in linear transects suffering a constant trampling intensity (25, 75, 100 and 200 passes/day). In addition, the study included the analysis of factors such as plant species, trampling intensity, the cumulative impact (day effect) and the type of footwear on plant variables. The results showed a decrease on plant cover and height influenced by cumulative (day) effect, an effect of trampling intensity and a different effect for each species. In contrast, shoe type affected only slightly the decrease in plant height. The evolution of plant cover revealed which species were most resistant to trampling. The disappearance of plant individuals during trampling appeared to be an impact index better than plant cover, because cover increased in some species when they were trampled thus introducing a bias.  相似文献   
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