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91.
卧龙自然保护区典型生态系统服务时空变化研究   总被引:1,自引:1,他引:0  
曹梦琪  蔡英楠  张丽  徐建英 《生态学报》2021,41(23):9341-9353
自然保护区作为生态系统服务的产生区和生物多样性保护的重点区,评估其关键生态系统服务,对提高保护区管理水平和生态保护与建设效率有重要意义。利用CASA模型、RUSLE模型、InVEST模型及水量平衡原理等方法分别定量评估了卧龙自然保护区2000年和2015年碳固定(NPP)、土壤保持、生境质量和水源涵养4种生态系统服务并分析了其时空分布及其变化特征,揭示了不同地形位梯度和土地利用类型上生态系统服务的差异,识别了生态系统服务的热点区域。研究结果揭示了2000-2015年4种生态系统服务及其变化的时空异质性:1)研究期间保护区4种生态系统服务供给量均有所增加,且增益面积大于减损面积;2)空间上,NPP、土壤保持和生境质量3种服务表现为东南高、西北低,水源涵养空间分布无明显规律,4种服务的空间分布特征均变化不大且保持相对稳定;3)4种生态系统服务空间分布及变化与地形位和土地利用类型有关。4种服务的高值和增益的优势分布区均位于较低地形位指数梯度上,以保护区东南部最为突出;林地和草地是对保护区生态系统服务贡献较大的土地利用类型,尤以林地突出;4)热点分析表明保护区东南部是主要的生态系统服务供给热点区,研究期间Ⅳ类热点区面积显著增加。结合研究区域生态系统特征和生态恢复与管理政策,探讨分析了目标生态系统服务时空变化的自然生态和社会经济驱动力,为本区域生态系统恢复和生物多样性保护提供依据和建议。  相似文献   
92.
正福建省位于我国东南沿海,亚热带气候和丰富植被为野生动物的生存和繁衍提供了良好的生态环境(丁晖等,2015)。武夷山位于福建北部,地理位置独特,雨量充足,植被多样且茂密,是众多动物赖以生存的场所,丰富的生物多样性资源使其成为世界著名的动物模式标本产地(罗桂环等,2016;耿宝荣等,2020),  相似文献   
93.
In southern Brazil, we investigated shark and ray capture records in an integral protection marine protection area (MPA) that allows fishing in that area. We found 10 shark and nine ray species, of which 88.5% and 66.2%, respectively, are endangered. Female adults and neonates of both sexes are abundant in the area, with records of stranding of large specimens, postcapture abortions and ovigerous capsules with fresh embryos on the beach. We suggest the application of continuous fisheries monitoring and an increase in guidelines on the capture of endangered species.  相似文献   
94.
该研究以宽阔水国家级自然保护区野生草本植物为研究对象,依据不同生境类型共选取10个样地进行调查,分析草本植物物种组成、区系特点及物种多样性的变化规律,为保护区草本植物物种多样性研究提供基础资料。结果表明:(1)样地内共有草本植物58科183属277种(含种下分类单位),以菊科(Asteraceae)、唇形科(Lamiaceae)、禾本科(Poaceae)和荨麻科(Urticaceae)为优势科;以凤仙花属(Impatiens)、堇菜属(Viola)、蓼属(Persicaria)和冷水花属(Pilea)为优势属。(2)在分布区类型中,科的热带分布成分最多,这与保护区所处的中亚热带植被环境的特点相吻合,属的温带地理分布比重最大(61.69%),但温带分布属内含种数较少,均以单种属为主,相反热带分布属的种数较多,并且属级在区系性质的分析中和科级相比更为敏感和可靠;由科和属的性质递变来看,热带性与温带性成分相互渗透,有较明显的过渡特征,属级的地理分布反映出保护区草本植物区系属于亚热带向暖温带过渡分布的性质。(3)各样地中草本植物群落组成有较大的差异,不同样地草本植物群落的α多样性指数与丰富度指数的变化格局不完全一致,但总体变化趋势是一致的,均在样地7的草本植物群落中达到峰值;相异性系数和Cody指数变化格局较为一致,总体呈现上升的趋势;样地8中草本植物多样性指数偏低,受人为干扰因素影响较大。  相似文献   
95.
我国是世界上植物多样性最丰富的国家之一, 1999年发布的《国家重点保护野生植物名录》(下称《名录》(第一批))明确了国家重点保护野生植物的范围, 为依法强化保护、规范无序开发利用、提高公众保护意识奠定了基础。20多年来, 我国野生植物多样性保护形势发生了很大变化, 需要对《名录》进行调整。2018年, 国家林业和草原局、农业农村部启动《名录》调整工作, 物种的遴选遵循了5条基本原则和4条补充性原则, 这些原则主要涉及中国珍稀濒危物种, 具有重要经济、文化、科研、生态等价值物种的入选以及部分物种的排除。经国务院批准, 2021年9月7日, 国家林业和草原局、农业农村部发布了调整后的《名录》, 包括真菌类、藻类、苔藓、石松类和蕨类植物、裸子植物和被子植物, 共计约1,101种(455种和40类)野生植物列入其中。本文简要介绍了《名录》调整的必要性、原则和程序及调整后的情况。  相似文献   
96.
Bats are a group of mammals well known for forming dynamic social groups. Studies of bat social structures are often based upon the frequency at which bats occupy the same roosts because observing bats directly is not always possible. However, it is not always clear how closely bats occupying the same roost associate with each other, obscuring whether associations result from social relationships or factors such as shared preferences for roosts. Our goal was to determine if bats cohabitating buildings were also found together inside roosts by using anti‐collision technology for PIT tags, which enables simultaneous detection of multiple tags. We PIT‐tagged 293 female little brown myotis (Myotis lucifugus) and installed antennas within two buildings used as maternity roosts in Yellowstone National Park. Antennas were positioned at roost entryways to generate cohabitation networks and along regions of attic ceilings in each building to generate intraroost networks based on proximity of bats to each other. We found that intraroost and cohabitation networks of buildings were significantly correlated, with the same bats tending to be linked in both networks, but that bats cohabitating the same building often roosted apart, leading to differing assessments of social structure. Cohabitation rates implied that bats associate with a greater number of their roost‐mates than was supported by observations within the roost. This caused social networks built upon roost cohabitation rates to be denser, smaller in diameter, and contain nodes with higher average degree centrality. These results show that roost cohabitation does not reflect preference for roost‐mates in little brown myotis, as is often inferred from similar studies, and that social network analyses based on cohabitation may provide misleading results.  相似文献   
97.
The purpose of this study was to examine undergraduate music education and performance alumni's career path, retrospective institutional satisfaction, and financial status. Data for this study were drawn from respondents from the 2010 administration of the nationwide, multi-institutional survey conducted by the Strategic National Arts Alumni Project (SNAAP). Regarding career path, nearly half of the music performance degree graduates reported performing as their current job, and slightly more than half of the music education degree graduates reported working in K–12 schools. Participants were generally satisfied with their institutional experiences, although relatively low levels of satisfaction were reported for networking and career advising services. The respondents reported being most satisfied with aspects of their current jobs that reflected the intrinsic benefits of contributing to a greater good, satisfying personal interests and values, and opportunities to be creative. The majority of the sample reported accruing student loan debt ranging between $10,000 and $30,000; however, no significant differences were found between groups, and 40 percent of the participants reported having accrued no debt at all. The reported annual income of the participants varied significantly, with music educators reporting higher earnings than performers.  相似文献   
98.
ABSTRACT

This article is a review and thematic analysis of the 2014 National Core Arts Standards (NCAS). Historically, there exists a gap between the arts and assessment-based educational practices. Thematic analysis of the NCAS reveals a policy striving to bridge the gap between the way arts educators envision arts in schools, and the current reality of assessment-based schooling in the United States. This policy could become the foundation for the recognition of the arts as academically rigorous subject matter, capable of existing and thriving in an assessment-oriented world; it remains to be seen as to how and if arts educators will use and adapt NCAS. Is the NCAS merely a symbolic policy or does it have the support behind it to be a material policy that truly creates change in the educational system?  相似文献   
99.
Recent archeological research at Hawaii Volcanoes National Park indicates that the story behind the imprinting of at least 1773 human footprints preserved in the Ka’u Desert ash is more complex than originally thought. Footprint impressions found in desert ash layers were previously believed to have been created by the army of the Hawaiian Chief Keoua on its way back from battle in 1790. When Kilauea is said to have erupted, apparently suffocating one group, the others made it out alive, apparently leaving their footprints in the then-wet ash, which evidently dried and hardened. These features have since been preserved, often under layers of volcanic sand. This simple explanation of an event still remembered in oral tradition, is not supported by the geologic evidence and the recent discovery of hundreds of archaeological features which indicate much more prehistoric activity in the area for at least two centuries prior to 1790. This suggests other people contributed to the footprints preserved in the desert ash.  相似文献   
100.
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