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981.
The study was carried out in the Altindere Valley, which is an area appropriate for tourism activities with natural, historical and cultural values through all four seasons, with Yazlik Village in the centre and including the surrounding sites Cosandere village, Altindere village, hamlets (The Hamlets) and plateau areas. In this study, the goal is to set forth the ecological-based tourism potential in line with the concepts of intactness; conservation-use balance; and sustainability at natural, historical and cultural sites through a determined planning approach. In this respect, assessments have been made on the study area on the basis of the ‘Ecological Evaluation Method’, which has been developed for urban areas. Through the determination of quotients, classification and quantitative assessment of unweighted values were found for natural and cultural elements that show percentage (%) dispersion at the area (slope, exposition, soil, forest, vegetation, existing areas use, historical and cultural structure). ‘Weighted values’ were calculated by multiplying the determined factor weights and the unweighted inside grid values of the factors. With the results of grid values obtained, 10.58% Very Good, 48.82% Good, 19.7% Average, 8.82% Weak, and 12.05% Very Weak, ‘Ecological Based Tourism Potential Areas According to Natural, Historical and Cultural Factors’ have been identified. 相似文献
982.
Ricardo Calado Tânia Pimentel Daniel F. R. Cleary Gisela Dionísio Cristóvão Nunes Teresa Lopes da Silva Maria Teresa Dinis Alberto Reis 《Marine Biology》2010,157(11):2427-2434
Larval decapods are commonly produced in captivity and employed in experiments to evaluate interspecific physiological and
biochemical differences. Currently, it is still unknown if different decapod species provided a common diet and exposed to
identical abiotic conditions produce newly hatched larvae (NHL) with similar fatty acid (FA) profiles. This study analyzed
the FA composition of NHL from five marine shrimp species (Lysmata amboinensis, L. boggessi, L. debelius, L. seticaudata and Rhynchocinetes durbanensis) fed a common diet and stocked at constant temperature. FA profiles of NHL differed significantly within and among genera.
NHL from species unable to molt from zoea I to zoea II in the absence of food (L. amboinensis, L. debelius and R. durbanensis) displayed the lowest FA contents. Researchers must be aware that providing a common diet to different species, even if closely
related, may not standardize the FA profile of NHL produced in captivity. 相似文献
983.
Biogeochemical cycle of arsenic and calculating the enrichment factor by using Li element 总被引:1,自引:0,他引:1
Abdullah Aksu Nuray Balkıs Mahmut S. Erşan A. E. Müftüoğlu Reşat Apak 《Environmental geochemistry and health》2010,32(4):303-306
In this study, the biogeochemical cycle of arsenic in the Bosporus and the Golden Horn, which have a two-layer stratified
structure, was investigated and the dominant feature in this cycle was observed to be the anthropogenic (domestic + industrial)
activities. On the contrary, in the rural areas which are far from human activities, such as İğneada, the seawater–atmosphere
interchange can be observed evidently in the periods covering the primary production. 相似文献
984.
Luísa Rodrigues Maria João Ramos Pereira Ana Rainho Jorge M. Palmeirim 《Behavioral ecology and sociobiology》2010,64(5):835-843
Dispersal and migratory behaviours are often important determinants of gene flow in wild species, and we have studied their
role using ringing-recapture data in the Portuguese population of Miniopterus schreibersii, a cave-dwelling bat that forms large maternity colonies. Juvenile dispersal, usually a major agent of gene flow, appears
to be negligible, as young females never settled to give birth in foreign colonies. Likewise, there was virtually no dispersal
of adult females to foreign maternity colonies. This strong philopatry virtually eliminated female-mediated gene flow, but
we found a great potential for male-mediated gene flow among colonies, as regional migrations temporarily joined both sexes
from different colonies in the same roosts, during the mating season. In fact, females from some colonies were more likely
to mate with males from foreign colonies than from their own, thus potentially bringing home genes of foreign males. In spite
of this abundant gene flow, we found a pattern of isolation by distance and even strong barriers to gene flow, which is explained
by the fact that migrations were usually too short to allow direct flow among distant colonies. We concluded that potential
gene flow is influenced by the distance between colonies and the availability of mating roosts between them. In addition,
we found this flow to be asymmetrical, with a dominant direction from the largest to the smallest colonies. Our ringing-recapture
estimates of potential gene flow based on dispersal and migratory behaviour are compatible with the genetic structure of the
population for both nuclear and mitochondrial DNA. Our conclusions have implications for the conservation of bats with a spatial
behaviour similar to that of M. schreibersii. Colonies should be managed individually because strict female philopatry not only promotes their isolation but also minimises
the contribution of immigration in rescuing declining colonies. Furthermore, the results underline the importance of preserving
mating roosts to maintain gene flow among colonies. 相似文献
985.
This paper presents an attempt to model the water balance in the metropolitan center landfill (MCL) in Salvador, Brazil. Aspects such as the municipal solid waste (MSW) initial water content, mass loss due to decomposition, MSW liquid expelling due to compression and those related to weather conditions, such as the amount of rainfall and evaporation are considered. Superficial flow and infiltration were modeled considering the waste and the hydraulic characteristics (permeability and soil-water retention curves) of the cover layer and simplified uni-dimensional empirical models. In order to validate the modeling procedure, data from one cell at the landfill were used. Monthly waste entry, volume of collected leachate and leachate level inside the cell were monitored. Water balance equations and the compressibility of the MSW were used to calculate the amount of leachate stored in the cell and the corresponding leachate level. Measured and calculated values of the leachate level inside the cell were similar and the model was able to capture the main trends of the water balance behavior during the cell operational period. 相似文献
986.
Composting technologies and control systems have reached an advanced stage of development, but these are too complex and expensive for most agricultural practitioners for treating livestock slurries. The development of simple, but robust and cost-effective techniques for composting animal slurries is therefore required to realise the potential benefits of waste sanitation and soil improvement associated with composted livestock manures. Cattle slurry solid fraction (SF) was collected at the rates of 4m(3)h(-1) and 1m(3)h(-1) and composted in tall (1.7 m) and short (1.2m) static piles, to evaluate the physicochemical characteristics and nutrient dynamics of SF during composting without addition of bulking agent materials, and without turning or water addition. Highest maximum temperatures (62-64 °C) were measured in tall piles compared to short piles (52 °C). However, maximum rates of organic matter (OM) destruction were observed at mesophilic temperature ranges in short piles, compared to tall piles, whereas thermophilic temperatures in tall piles maximised sanitation and enhanced moisture reduction. Final OM losses were within the range of 520-660 g kg(-1) dry solids and the net loss of OM significantly (P<0.001) increased nutrient concentrations during the composting period. An advanced degree of stabilization of the SF was indicated by low final pile temperatures and C/N ratio, low concentrations of NH(4)(+) and increased concentrations of NO(3)(-) in SF composts. The results indicated that minimum intervention composting of SF in static piles over 168 days can produce agronomically effective organic soil amendments containing significant amounts of OM (772-856 g kg(-1)) and plant nutrients. The implications of a minimal intervention management approach to composting SF on compost pathogen reduction are discussed and possible measures to improve sanitation are suggested. 相似文献
987.
Nora Escribano Arturo H. Ariño Andrea Pino-del-Carpio David Galicia Rafael Miranda 《Conservation biology》2021,35(6):1894-1902
Zoos and aquaria, often regarded as preservation-cum-entertainment enterprises, are also actors in the effort to curb the biodiversity crisis: raising awareness, supporting conservation, and conducting research. We assessed trends in zoo and aquaria research topics and study organisms over time worldwide. For the zoos and aquaria registered in the Species360's Zoological Information Management System and the World Association of Zoos and Aquariums, we compiled metadata on their research published in the peer-reviewed literature indexed in Scopus and carried out a keyword frequency analysis. The production of scientific papers by zoos increased at a much faster rate than the average accrual of scientific papers in the literature. Evolution of research themes ran parallel to that of biological sciences (e.g., development of molecular genetics or increased awareness about conservation). The focus of 48.5% of zoo-led research was on vertebrates, of which mammal research was 33.7%. Whether zoos are effectively contributing to conservation may still be debatable, but our results highlight their institutional efforts to increase knowledge about the species in their care. 相似文献
988.
Soğukpınar Fatih Erkal Gökhan Özer Hüseyin 《Environmental science and pollution research international》2023,30(13):35891-35912
Environmental Science and Pollution Research - Energy is an essential requirement for sustainable development, society, and the world. Turkey has been trying to increase the use of renewable... 相似文献
989.
Rocío López de la Lama Nathan Bennett Janette Bulkan David Boyd Kai M. A. Chan 《Conservation biology》2023,37(4):e14068
Privately protected areas (PPAs) are a potentially innovative conservation tool. Legal recognition is necessary for their success, especially where there are institutional challenges to nature conservation, such as in South America. Although PPAs have increased in South America since the early 2000s, there is a critical information gap pertaining to their legal frameworks. We analyzed the level of landowner commitment to and governmental support for PPAs across countries in South America that officially recognize PPAs. We analyzed the legal framework governing PPAs and reviewed literature on them. This process was done in English and Spanish. The information we gathered was validated by 16 conservation experts from 10 South American countries. Because Peru is 1 of only 2 South American countries where local communities create and manage PPAs, we studied Peruvian PPAs in more detail by examining official creation documents and interviewing 13 local conservation professionals. We found inadequate minimum duration of PPAs and vague guidelines for conducting economic activities within them and a lack of governmental support (e.g., financial and technical support) for PPAs. Support was limited to the exemption from rural property taxes, which are relatively low compared with countries outside South America. In Peru, PPAs run by individuals and communities needed different legal frameworks because they were created with different objectives and had different sizes and duration of commitments. The prompt improvement of legal frameworks across South America is necessary for PPAs to achieve their aim of being places for enduring nature conservation in the region. 相似文献
990.
João L. Guilherme Victoria R. Jones Inês Catry Martin Beal Maria P. Dias Steffen Oppel Juliet A. Vickery Chris M. Hewson Stuart H. M. Butchart Ana S. L. Rodrigues 《Conservation biology》2023,37(1):e14002
The conservation of long-distance migratory birds requires coordination between the multiple countries connected by the movements of these species. The recent expansion of tracking studies is shedding new light on these movements, but much of this information is fragmented and inaccessible to conservation practitioners and policy makers. We synthesized current knowledge on the connectivity established between countries by landbirds and raptors migrating along the African–Eurasian flyway. We reviewed tracking studies to compile migration records for 1229 individual birds, from which we derived 544 migratory links, each link corresponding to a species’ connection between a breeding country in Europe and a nonbreeding country in sub-Saharan Africa. We used these migratory links to analyze trends in knowledge over time and spatial patterns of connectivity per country (across species), per species (across countries), and at the flyway scale (across all countries and all species). The number of tracking studies available increased steadily since 2010 (particularly for landbirds), but the coverage of existing tracking data was highly incomplete. An average of 7.5% of migratory landbird species and 14.6% of raptor species were tracked per country. More data existed from central and western European countries, and it was biased toward larger bodied species. We provide species- and country-level syntheses of the migratory links we identified from the reviewed studies, involving 123 populations of 43 species, migrating between 28 European and 43 African countries. Several countries (e.g., Spain, Poland, Ethiopia, Democratic Republic of Congo) are strategic priorities for future tracking studies to complement existing data, particularly on landbirds. Despite the limitations in existing tracking data, our data and results can inform discussions under 2 key policy instruments at the flyway scale: the African–Eurasian Migratory Landbirds Action Plan and the Memorandum of Understanding on the Conservation of Migratory Birds of Prey in Africa and Eurasia. 相似文献