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61.
This article provides a case study of small-scale private sector provision of water supply in Paraguay, where the Government has sought sector policy reforms that would encourage private investment in drinking water supply. Ironically, while the Government has focused almost entirely on garnering the interest of large private international water companies, much smaller local firms have already made significant investments in drinking water services for the poor, all without any participation or encouragement from the Government. Outside Paraguay's two major cities, Asunción and Ciudad del Este, large numbers of aguateros currently provide piped potable water to lower-income people. Though the aguateros have little legal footing — they are in many respects informal and unregulated —they have constructed as much as one third of all the new drinking water connections in these two cities over the past 20 years. The small-scale water systems in Paraguay offer a model of financial, economic, and water-use efficiency. This article asserts that an abundance of groundwater resources, cheap access to electricity for pumping, and a spirit of informal investment, among other variables, has spawned widespread use of this approach. This article documents and analyzes the features of these independent small-scale water providers in Paraguay and the efficiency they bring to the use of water resources in meeting drinking water demands among the poor. It also cautions against policies that may trample on such entrepreneurial spirit in the name of State-managed privatization.  相似文献   
62.
The development and implementation of new procedures and operational changes in the production processes constitutes a powerful tool for the practical application of Cleaner Production in industries. In this work an operational change (new procedure) was developed for the elaboration of a type of beer which uses sugar as malt adjunct. The change consists in processing separately the three main components of the beer wort: malt extract, sugar and water, and use them properly in a different sequence than that used up to date in the traditional process. The new procedure was successfully assayed on industrial scale in Tínima brewery, located in Camagüey, Cuba, obtaining a good quality beer, technological and economical advantages with benefits for the environment, registering significant savings in energy (49%), sugar (4%), water (7%) and caustic soda (3%) consumption; and diminishing the surplus hot water (74%), waste generation (11%) and greenhouse gases emission (21%). Beer production capacity is increased also almost three times. With the application of the new technology to the Cuban beer type of 8 °P, it was achieved a total saving of US$ 481.83/1000 hL of beer produced.  相似文献   
63.
In the Brazilian Amazon, private land accounts for the majority of remaining native vegetation. Understanding how land‐use change affects the composition and distribution of biodiversity in farmlands is critical for improving conservation strategies in the face of rapid agricultural expansion. Working across an area exceeding 3 million ha in the southwestern state of Rondônia, we assessed how the extent and configuration of remnant forest in replicate 10,000‐ha landscapes has affected the occurrence of a suite of Amazonian mammals and birds. In each of 31 landscapes, we used field sampling and semistructured interviews with landowners to determine the presence of 28 large and medium sized mammals and birds, as well as a further 7 understory birds. We then combined results of field surveys and interviews with a probabilistic model of deforestation. We found strong evidence for a threshold response of sampled biodiversity to landscape level forest cover; landscapes with <30–40% forest cover hosted markedly fewer species. Results from field surveys and interviews yielded similar thresholds. These results imply that in partially deforested landscapes many species are susceptible to extirpation following relatively small additional reductions in forest area. In the model of deforestation by 2030 the number of 10,000‐ha landscapes under a conservative threshold of 43% forest cover almost doubled, such that only 22% of landscapes would likely to be able to sustain at least 75% of the 35 focal species we sampled. Brazilian law requires rural property owners in the Amazon to retain 80% forest cover, although this is rarely achieved. Prioritizing efforts to ensure that entire landscapes, rather than individual farms, retain at least 50% forest cover may help safeguard native biodiversity in private forest reserves in the Amazon. Umbrales de Pérdida de Especies en los Paisajes Fronterizos de Deforestación en el Amazonas Ochoa‐Quintero  相似文献   
64.
Journal of Material Cycles and Waste Management - Food waste is a serious problem worldwide. There is a lot of waste in the food sector, while we still have a significant percentage of people who...  相似文献   
65.
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