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914.
The aim of this work is to assess and understand the social drivers that determine the willingness to pay for sustainable management measures to preserve a Natura 2000 area. These social drivers of the support for nature conservation were then included in the design of economic instrument to support nature conservation. In a contingent valuation exercise, the local population in the Cabezo de la Jara and Rambla de Nogalte protected areas (SE Spain) stated their willingness to pay for sustainable management measures aimed at their conservation. Among the socio-demographics, environmental attitudes and experiential drivers, income and environmental commitment were found to be the only significant drivers in support of nature conservation, revealing preference heterogeneity. Economic instruments, specifically green taxes and user fees, are proposed, taking into account the sources of heterogeneity in order to ensure financial support for the measures and greater social acceptability. Hence, our research adds to the existing literature through the design of an economic instrument to support nature conservation, considering preference heterogeneity.  相似文献   
915.
In Iran, mangroves are located in the south of the country, where they fulfill essential ecosystem functions, but some parts of them have been destroyed for various reasons in recent years so that it seems necessary to have a management plan consistent with the conservation of this ecosystem. But, it needs knowledge of the trend of and reasons for the degradation of these forests. So, the primary idea of this research was to discover the factors involved in the degradation of these forests and how to manage them. So, the research first used the remote sensing technique to determine the rate of their degradation over the last 20 years. Then, using the Delphi technique, 45 factors were identified for the degradation of these forests and they were classified into five categories including climatic and environmental, anthropogenic, socioeconomic, psychological, and policymaking and legal. Finally, the analytic hierarchy process (AHP) was used to rank these factors within two management paradigms of remediability and preventability so that the ecosystem can be soundly managed by classifying these factors. Overall, the results can provide policymakers with new insights into forest management and the policies presented here can contribute to the sustainability of this ecosystem.  相似文献   
916.
Outdoor recreation can negatively impact wildlife. Shorebirds are especially sensitive because they often inhabit beaches used for recreation. Beaches at Oregon Dunes National Recreation Area (ODNRA) provide critical habitat for the federally threatened western snowy plover (WSPL) (Charadrius nivosus), which nests and forages in open sand. The ODNRA uses rope fencing and signs to communicate closures of WSPL habitat, but past efforts have not been highly successful. To improve compliance with closures, this study tested signs with messages based on the focus theory of normative conduct (i.e., Normative) and the extended elaboration likelihood model (i.e., Narrative). In an experimental design, the two treatment signs were compared to a control (an existing sign). We examined how the messages affected visitor attention to signs and impacted compliance with WSPL restrictions. Nearly 800 people were unobtrusively observed as they approached the sign and their reading behavior was documented. At regular intervals, an observer scanned the beach to count the number of people in and out of compliance with the regulations. Approximately one third of visitors read the treatment signs, while only 5% read the control sign. The Narrative sign was the most effective in deterring entry into WSPL nesting habitat. Findings suggest that a narrative format may encourage visitors to perform wildlife friendly behaviors. However, because many visitors still recreated inside WSPL nesting habitat after being exposed to signs, signs should be used to supplement strategies such as fencing or personal contact.  相似文献   
917.
The flammable ecosystems are evolutionary dependent on the periodic action of fire. Several environmental factors, both at local and landscape scales, can affect fire regimes in these ecosystems differently. Here, we evaluated the influence of local and landscape features on two parameters of the fire regime of a flammable protected area of the Brazilian savanna: The Chapada Diamantina National Park. We characterized both fire frequency and the time since the last fire, from 1990 to 2019 and measured five environmental predictors (tree canopy cover, altitude, water surface, predominant land use and distance to the nearest municipality). We used Generalized Additive Models for Location, Scale and Shape (GAMLSS) to assess the influence of environmental predictors on the measured fire regime parameters. We found a large interannual variation in the total annual area burned in the studied period. In total, 68 % of the protected area (1030 km2) was burned at least once and 32 % (486 km2) was unaffected by fires during the study period. Predominant land use, distance to the nearest municipality, tree cover and the interaction between tree cover and altitude were negatively related to fire frequency, while the water surface and altitude positively influenced fire frequency in the park. Compared to older fires, recent fires occurred in landscapes at lower altitudes and with lower tree cover. Our results demonstrate that the fire frequency and time since the last fire were highly variable across the park, reflecting the strong influence of landscape heterogeneity on their parameters.  相似文献   
918.
To prioritise conservation actions and management strategies for threatened forest deer species at the Atlantic forest, we aimed to identify and describe the most suitable habitat areas for forest deer species and to indicate conservation measures for state agents and local communities. We adopt an approach based on ecological niche modelling, key variable thresholds and spatial analyses. In addition, we associated our approach with a human influence index, an invasive species dataset of occurrences, protected area cover and IUCN category. We indicate 2 % (484 km2) of the Atlantic forest cover as conservation priority areas (CPAs). Of these, 56.8 % are outside protected areas, 20.7 % are inside IUCN categories i, ii and iii protected areas, 19.9 % are inside IUCN categories iv, v, and vi protected areas, and 2.6 % are inside indigenous areas. Also, we indicate the most relevant protected areas for deer conservation in the Atlantic forest. The CPAs were classified into more human-influenced areas (MHIA) and less human-influenced areas (LHIA), and we identified 21 significant (greater than120 km2) continuous CPAs outside protected areas. We highlight actions in several perspectives of human influence, governance levels and law protection that would rationalise the use of funds and human resources.  相似文献   
919.
为揭示寒旱区冰封期富营养化湖泊水体中浮游植物群落结构及其与水质指标的响应关系,该研究以乌梁素海为对象,于2019年1月在湖区设立12个采样点采集水样及浮游植物,通过对浮游植物定性定量检测和水体理化性质测定分析,以明确冰封期乌梁素海浮游植物群落结构空间变化特征及主要水质指标的分布规律;结合RDA分析和Pearson相关性分析揭示了浮游植物与水质指标的响应关系,为水体富营养化程度评估及防控提供理论依据。结果显示:(1)冰封期乌梁素海12个样点的水质指标特征差异明显,各水质指标从北到南具有不同的变化趋势。(2)冰封期乌梁素海共检出浮游植物61种,其中隐藻门的丰度最高(4.76×10^(6)个·L^(-1)),甲藻门的生物量最高(18.09 mg·L^(-1)),但湖区不同位置的优势浮游植物类群有所差异,北湖区蓝隐藻和伪鱼腥藻丰度明显高于南湖区。(3)不同种类的浮游植物在空间分布上存在明显的差异,且在P3样点的多样性最低,P8样点的多样性最高,并发现中、下湖区物种类型多且组成较为均匀。(4)浮游植物的丰度与TP呈显著正相关关系,生物量与TP呈极显著正相关关系,多样性指数与TP呈正相关关系。研究表明,冰封期乌梁素海水体处于中等营养水平,水体中总磷(TP)含量是影响浮游植物物种丰度和生物量的主要影响因子;寒旱区冰封期富营养化湖泊浮游植物分布特征为北湖区隐藻门、蓝藻门和甲藻门占优势;南湖区中绿藻门丰度最高。  相似文献   
920.
该研究以查阅文献和野外实地调查相结合的方法,对锡林郭勒草原国家级自然保护区种子植物进行调查、统计、排序,并对该区系种子植物的种类组成、水分生态类型、生活型及种的地理成分进行分析。结果表明:锡林郭勒草原国家级自然保护区有野生种子植物856种,分别隶属于87科,345属;其中,裸子植物3科,5属,11种;被子植物84科,340属,845种。植物水分生态类型以中生植物为主,共559种,占区系总种数的65.30%;旱生植物213种,占区系总种数的24.88%。生活型以草本植物为主,占区系总种数的88.67%。区系中种的地理成分较为复杂,既反映出保护区植物地域性强的特征,也反映出该区域生境类型多样、植物丰富度高的特征。  相似文献   
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