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51.
Models of eco‐industrial parks (EIPs) might help us transform our production systems by fostering the emergence of sustainable EIPs since such models have the potential to support the decision‐making processes of cooperative companies that participate and to decrease operational uncertainties. In this article, a conceptual framework for modeling the operation of EIPs is presented. The framework is underpinned by complex adaptive systems theory, industrial ecology, and an analysis of the experiences of existing EIPs. The proposed framework draws on the observed strengths of two types of industrial symbiosis models—planned eco‐industrial parks (PEIPs) and EIPs that developed through self‐organizing symbiosis (SOS)—as well as their observed weaknesses and the features of complex adaptive systems. From this analysis, five key properties to be modeled are deduced: functionality, reliability, life span, theoretical knowledge, and adaptability. It is proposed that the properties of functionality and theoretical knowledge are determined by the goals of the EIP and its member companies, while the property of adaptability is determined by the understanding that the companies in an EIP have of the environment surrounding the EIP, while the properties of reliability and life span are determined by the internal and external relationships of the companies that make up an EIP.  相似文献   
52.
Human harvests can unwittingly drive evolution on morphology and life history, and these selective effects may be detrimental to the management of natural resources. Although theory suggests that harvest refuges, as sources of unselected animals, could buffer the effects of human exploitation on wild populations, few studies have assessed their efficiency. We analyzed records from >7000 trophy bighorn rams (Ovis canadensis) harvested in Alberta, Canada, between 1974 and 2011 to investigate if the movement of rams from refuges toward harvested areas reduced the effects of selective harvesting on horn size through phenotypic rescue. Rams taken near refuges had horns on average about 3% longer than rams shot far from refuges and were slightly older, suggesting migration from refuges into hunted areas. Rams from areas adjacent to and far from harvest refuges, however, showed similar declines in horn length and increases in age at harvest over time, indicating a decreasing rate of horn growth. Our study suggests that the influx of rams from refuges is not sufficient to mitigate the selective effects of sheep trophy harvest. Instead, we suggest that selective hunting of highly mobile animals may affect the genetic structure of populations that spend part of the year inside protected areas.  相似文献   
53.
Zoo visitors perceive naturalistic enclosures (i.e. those attempting to replicate identifiable parts of the landscape of the species' habitat) as those that best satisfy the biological needs of the animals, and ensure therefore their welfare. However, the provision of a suitable environment with the resources that will allow the animals to satisfy their main biological needs in naturalistic enclosures has never been systematically explored; instead, it has been assumed. In this study we provide evidence that supports the general idea that naturalistic designs provide suitable environments for the animals. For that purpose, we analyzed 1,381 naturalistic and non-naturalistic enclosures in 63 Spanish zoological parks. In order to assess the suitability of the environment provided within each enclosure, a number of aspects related to the animals' main biological requirements were analyzed. We found a relationship between naturalistic designs and the suitability of the environment for the species housed. Most naturalistic enclosures (77.8%) provided suitable environments for their inhabitants. Non-naturalistic ones also had suitable environments, but in a lower percentage (39.7%). These results should be taken into account during zoo inspection and accreditation appointments, where enclosure suitability must be assessed in an accurate and fast manner. In this regard, a naturalistic design can be used as an adjunct indicator of enclosure suitability, but not exclusively, as not every naturalistic enclosure was suitable for the animals, neither as an indispensable one, given that near 40% of non-naturalistic ones were appropriate for the species housed.  相似文献   
54.
Feeding patterns of mosquitoes in six Brazilian environmental preservation areas were analyzed by the precipitin technique. The mosquito populations were captured using Shannon traps during different time periods. Bird, cow, dog, horse, opossum, human, and rodent antisera diagnostic tests were employed and results were analyzed by calculating the Sørensen similarity index and using the null‐model test. Of the 647 analyzed specimens, 443 reacted to the utilized antisera, of which 331 reacted to one blood source, with the most frequent being birds (49.4%); and 112 specimens reacted to two blood sources, with the most frequent combination from birds + rodents (14.3%). The feed profiles demonstrated that Anopheles albitarsis, An. evansae, Aedes fulvus, Psorophora albigenu, Ps. albipes, Ps. ferox, and Mansonia titillans fed predominantly on birds. The similarity index showed that in some localities An. cruzii, Chagasia fajardi, Ae. scapularis, Ae. serratus, Haemagogus leucocelaenus, Ps. albigenu, and Ps. ferox presented similar dietary habits. The null‐models test indicated that species from SMSP, INP, CGNP, and THP demonstrated an aggregate pattern, while species from SONP and SBNP showed a random pattern. The mosquitoes fed predominantly on birds, but from an epidemiological standpoint, the eclectic feeding habits were found to be constant among the mosquitoes analyzed.  相似文献   
55.
Anthropogenic noise is becoming more prevalent in the world and has been shown to affect many animal species, including birds. The impact of such noise was measured in Neotropical urban parks to assess how the noise affects avifauna diversity and species richness. We sampled bird species, and concurrently measured sound pressure (noise) levels (Leq, equivalent noise levels) in eight urban green areas or parks located in a large city (Belo Horizonte) in south‐eastern Brazil over a 1‐year period. The diversity of sampled points was measured by means of total species richness, Fisher's alpha and Shannon–Wiener diversity indices. Noise levels within all parks were greater than those in natural areas. We found that an increase in noise levels and the area of open habitats surrounding sampling points were negatively related to species richness. Social factors reflecting increased urbanization, such as higher incomes, were also negatively correlated with bird species richness. However, noise was the factor that explained most of the variance. These results suggest that anthropogenic noise can have a significant negative impact on the conservation value of urban parks for bird species.  相似文献   
56.
Wild Mushroom Markets in Central Mexico and a Case Study at Ozumba. More than 200 species of wild edible mushrooms are consumed in Mexico, and over 100 are sold in local, regional, and wholesale markets. This paper analyzes general trends in the commercialization of wild edible mushrooms at twelve markets in central Mexico, where at least 90 species are sold and more than 100 local names were registered. The paper then focuses its analysis on the traditional market at Ozumba (state of Mexico) near Izta-Popo and Zoquiapan national parks. In 2006, 411 stands selling more than 60 mushroom species were sampled throughout the year to record information on the vendors and the species they sold. The greatest diversity of species was recorded in July and August. More than 90% of the wild mushroom vendors were women, and 64% were 40 to 60 years old. The economic value of wild mushrooms in some regions of Mexico appears to contribute to the maintenance of traditional ethnobiological knowledge, generally observed to be in overall decline.  相似文献   
57.
The three largest water bodies of East Africa, Lake Victoria, Tanganyika, and Malawi contain an estimated number of 2,000 endemic cichlid fish species, in addition, to a mostly uncounted wealth of invertebrates. While the terrestrial diversity is reasonably well protected, as economic and touristic interests coincide with biological conservation strategies, this is not the case for most African lakes and rivers. Nonetheless, it must be promoted that these aquatic ecosystems also deserve protection. Conservation strategies for aquatic biota have so far been the same as for terrestrial environments, i.e., by declaring biodiversity hotspots national parks. Such parks also contain rivers and lake shores. Here, I argue that it seems questionable that this strategy will work, given strong micro-geographic structure of the species flocks and the great degree of local endemism. I suggest a novel strategy for protecting African Lake communities that accounts for local endemism, derived from recent molecular phylogenetic and phylogeographic studies on East African cichlid fishes. While connectivity is the major problem for terrestrial and marine national parks, to ensure a large enough effective population size of the protected animals, this is not the case in most taxa of African rivers and lakes, where local endemism prevails. For example, most littoral cichlid species are subdivided into numerous distinct “color morphs” with restricted distribution, and unlike marine fishes with planktonic larvae display brood care with small offspring numbers. It is argued that the establishment of “micro-scale protected areas,” a large number of small stretches of strictly protected coast line, each only some hundreds of meters long, is likely to work best to preserve the littoral communities in African lakes. Such protected zones can sustain a reasonably effective population size of littoral species, serve as protected spawning ground or nursery area for pelagic species, and at the same time re-seed neighboring populations that are exploited continuously. As long-term stability of littoral fishing grounds is in the immediate interest of village communities, such small protected areas should be managed and controlled by the local communities themselves, and supervised by governmental institutions.  相似文献   
58.
In situ conservation is an effective strategy to protect biodiversity, and Brazil has one of the largest protected area (PA) systems in the world. However, the distribution of Brazilian PAs is uneven and the Caatinga drylands are poorly protected. As financial resources are essential for effectively managing PAs, we analyzed the Brazilian Government's budget allocated to 20 federal PAs in the Caatinga between 2008 and 2014, which ranged from 231,575 USD in 2008 to 13.5 Mi USD in 2011. Neither expenses, nor the availability of funds, were homogeneous among PAs or throughout the years. Land acquisition in a single PA consumed ~75% of the budget, and the two smallest PAs received proportionally the most money. Excluding land acquisition, the 20 PAs received 0.50 USD/ha/year. Funds were allocated not to biodiversity conservation per se but mainly to securing offices, cars, and equipment. From 2012 onwards, the PA budget was reduced. Even including salaries, the budget allocated for these PAs is ~13 times lower than what the Ministry of the Environment declared necessary for the basic operation of protected areas in Brazil, 1.5 times lower than values spent worldwide, up to 5 times lower than spent in Latin American and African parks, and up to 72 times lower than spent in the European Union, exposing one cause of the precarious situation of the Caatinga PAs.  相似文献   
59.
In many developing nations, “paper parks”, or protected areas that have little or no formal management on the ground, have resulted from the failure of protected area systems to achieve their foremost goal: biodiversity conservation. This analysis incorporates biophysical, socioeconomic, and land use/tenure data collected by a multi-disciplinary team of Guatemalan and American researchers in order to identify potential management plans and multiple-use/concession arrangements. The Sierra Chinajá is a classic paper park protected area in Guatemala. Many factors have rendered Guatemalan protected areas management policies ineffectual in the Sierra Chinajá despite the fact that it has been an “area of special protection” since 1989. Proximate causes of forest conversion mask underlying driving forces responsible for rapid biodiversity loss. Despite the fact that Guatemala’s protected areas management system is similar to that promoted by international conservation organizations it has yet to effectively conserve biodiversity. These factors suggest that protected areas management in Guatemala, and other developing nations possessing unique cultural and natural histories, must be rooted in the local context as promulgated by the local non-governmental organization ProPéten in their proposal for an official Indigenous Reserve category. The proposal suggests the devolution of management responsibilities from federal institutions to local communities in the effort to develop a community-based, site specific conservation agenda.
Resumen  En muchos países en desarrollo, las “áreas protegidas en papel” o parques que no poseen un plan de manejo formal, han sido el resultado de la incapacidad del sistema nacional de áreas protegidas de alcanzar su meta mas importante: la conservación de la biodiversidad. El siguiente análisis incorpora datos biofísicos, socioeconómicos, de uso y tenencia de la tierra recolectados por un grupo multidisciplinario de investigadores guatemaltecos y norteamericanos con el objetivo de formular una estrategia de conservación que incorpore concesiones de usos múltiples. La Sierra de Chinajá es un ejemplo clásico de un “área protegida en papel” en Guatemala. Muchos son los factores por los cuales la política de áreas protegidas ha fracasado en la Sierra de Chinajá, a pesar de estar clasificada como un “área de Protección Especial” desde 1989. Las causas subyacentes responsables por el cambio en la cobertura forestal están escondidas debajo de los síntomas más visibles de la perdida de biodiversidad. A pesar de que el Sistema Guatemalteco de áreas Protegidas es similar al promovido por organizaciones internacionales aun no es efectivo en la conservación de la biodiversidad. Estos factores sugieren que el manejo de las áreas protegidas en Guatemala, y en otros países en desarrollo que poseen historias naturales y culturales únicas, deben estar enraizadas en el contexto local, como ha sido propuesto por la organización Pro-Peten en su propuesta por una categoría de manejo denominada Reservas Comunitarias Indígenas. La propuesta sugiere la delegación de la protección la biodiversidad de instituciones estatales a las comunidades locales con el propósito de establecer una agenda de conservación basada en el manejo comunitario.
  相似文献   
60.
A comparative study of butterfly communities in 15 urban/suburban remnants of tropical semideciduous forest in Campinas (São Paulo state, SE Brazil; 24°S, 47°W), with areas from 1.0 to 252ha and widely varying histories and environments, shows that the most significant factors, besides area and sampling time, distinguishing the sites and influencing their diversity (80–702 species) and composition are connectivity, permanent water, vegetation, flowers, and human impact (negative, including pollution). The diversified Nymphalidae butterflies (38–213 species) and especially two fermented-bait-attracted groups (Satyrinae, 2–30 species, and Biblidini, 9–44 species), are among the more useful indicators of the quality and diversity of the environments in these fragments. Effective conservation of butterfly communities in tropical cities may be achieved by maintenance of arboreal green corridors along streets and watercourses between moderately large (>10ha) humid areas, not near to the most built-up or polluted city centre(s), and the inclusion within these areas of ponds or streams, diversified native forest, and open vegetation including abundant nectar-rich flowers.  相似文献   
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