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921.
Through a quantitative approach, this study aimed to clarify the changes in the number of visitors and visits to green spaces according to green space type before and after the COVID-19 pandemic. We explored the changes in the proportion of repeat visitors and the distance between green spaces and visitors’ places of residence. We used KDDI Location Analyzer, which performs novel analysis using mobile phone GPS and census data. The study area included 10 target sites (urban parks and nature trails in the backcountry) located in the Sapporo metropolitan area in Japan. The survey period included snow-free seasons from 2019 to 2021, and 2019 was considered the period “before the pandemic.” The results revealed that the number of visits during the pandemic increased compared with those before the pandemic, except for those of urban parks near the city center. In 2020, the proportion of repeat visitors increased for all 10 target sites. In addition, since the outbreak of the pandemic, distances between all urban parks and visitors’ residences decreased. The same trend was observed for nature trails in the backcountry close to the city center. These findings indicate a generally decreasing trend in the number of visits to green spaces as many people have been refraining from visiting the site since the outbreak of the pandemic. Contrastingly, the number of visits by repeat visitors who reside close to the target sites has increased in some cases, which compensated for the general decreases. 相似文献
922.
Urban warming affects many millions of city dwellers worldwide. The current study evaluated the extent to which trees reduce air and surface temperatures in urban settings across Greater Sydney, Australia. Summertime air and surface temperatures were measured directly in the shade of 470 individual trees planted in three contrasting contexts (parks, nature strips, asphalt) and compared with temperatures in paired adjacent areas receiving full sunlight. Differences between shade and sunlit temperatures were evaluated against measured morphological traits (leaf area index [LAI], clear stem height, crown depth, height and diameter at breast height) for all trees. On average, tree shade reduced mean and maximum air temperatures by 1.1 °C and 3.7 °C, respectively. Temperatures of standardised reference surfaces (black and white tiles and artificial grass) in tree shade were up to 45 °C lower compared to full-sun exposure, and were also lower in parks and nature strips compared to asphalt settings. The surface temperature of shaded natural grass was cooler compared to sunlit natural grass, although this difference did not vary between nature strip and park settings. The magnitude of air and surface temperature reductions due to tree shade was significantly, positively related to tree-level LAI and these relationships were stronger in asphalt and park contexts compared to nature strips. These findings can inform decisions made by urban managers and planners around the selection of tree characteristics to enhance cooling benefits in different contexts, as an important step towards more liveable and resilient cities. 相似文献
923.
Conserving urban biodiversity is often promoted as a ‘win-win’ nature-based solution that can help align public health and biodiversity conservation agendas. Yet, research on the relationship between biodiversity and psychological well-being reveals inconsistent and complex results. This body of research is also restricted to a few socio-cultural and environmental contexts and tends to ignore differences in individual characteristics, such as nature relatedness (i.e., emotional affinity to nature) and ecological knowledge, that can influence people’s experience of biodiversity. The aim of this interdisciplinary research is to explore the relationships between biodiversity and psychological well-being, and test the moderating effect of nature relatedness and ecological knowledge on these relationships. An ecological survey was conducted in 24 small urban gardens in Israel to measure the richness and abundance of birds, butterflies and plants, as well as land cover characteristics. In parallel, a social survey (close-ended questionnaires) was conducted in-situ to measure psychological well-being, nature relatedness, ecological knowledge, perceived species richness and socio-demographic variables. Psychological well-being measures were mostly associated with the cover of woody species, perceived species richness, and to a lesser extent, with actual species richness and abundance, for all taxa. Nature relatedness moderated these relationships. Respondents with high nature relatedness demonstrated positive well-being-richness relationships, while those with intermediate, or low nature relatedness showed no, or even negative relationships, respectively. Opposite relationships were recorded for bird abundance. Overall, individuals demonstrated poor ecological knowledge and this variable moderated only few relations between well-being measures, perceived butterfly richness and bird abundance. Our results demonstrate that one-size-does-not-fit-all when considering the relationship between psychological well-being and biodiversity, and that affinity to nature is a key moderator for this relationship. Designing urban green spaces that provide inclusive and meaningful nature experiences and foster emotional affinity to nature, is therefore key to aligning ecological and social objectives for sustainable urban planning. 相似文献
924.
广东鹅凰嶂自然保护区珍稀濒危植物及保育 总被引:1,自引:0,他引:1
鹅凰嶂自然保护区有珍稀濒危植物20科27属18种.分析了这些植物的分布状况、分布在此区的可能原因和资源价值,并提出了相应的保育对策和建议 相似文献
925.
926.
选择典型线路和地段对云南双柏恐龙河州级自然保护区进行系统的植物区系考察,从科、属、种对种子植物区系特征进行研究。结果表明,保护区植物种类丰富,共记录有维管束植物192科736属1 204种(含种下等级);保护区地理位置特殊,从南北而言是东亚植物区与古热带植物区的南北交汇区域,东西方向属于中国—喜马拉雅植物区系和中国—日本森林植物区系交汇过渡区域;保护区植物区系是东亚植物区系的一部分,具有明显的热带性质,呈热带植物区系和亚热带、温带植物区系交汇的特点。 相似文献
927.
锐齿槲栎是广泛分布于我国暖温带和亚热带山地中海拔地段的主要优势种,以五道峡国家级自然保护区内的锐齿槲栎群落为研究对象,通过种群年龄结构及数量动态变化,生活型谱及生长模型方面的研究,分析五道峡国家级自然保护区锐齿槲栎群落特征。结果表明,锐齿槲栎龄级结构中,个体数量在Ⅲ~Ⅵ龄级占比最大,种群中低龄个体数量充足;种群数量动态指数显示锐齿槲栎种群呈现增长趋势,但种群稳定性差且抗干扰能力较弱;生活型谱分析发现,占比最高的属于高位芽植物,且呈随海拔升高占比逐渐降低的趋势,植物生活型谱大致呈现“L”型;生长模型的研究表明,三次函数模型的决定系数R2达到最大值,且经过T检验,表明三次函数模型可以很好地用来拟合锐齿槲栎胸径—树高的关系。建议在原地保护的基础上进行科学的管理,并充分调动群众的积极性,为种群营造稳定的生存环境,促进种群的长期发展。 相似文献
928.
广东英德石门台自然保护区共有珍稀植物45种,国家重点保护植物23种(其中国家I级保护植物2种,国家II级保护植物21种),珍稀濒危植物36种(其中濒危2种,渐危20种,稀有14种)。这些植物具有种类丰富、热带性强、起源古老等特点。在探讨其濒危原因的基础上,笔者提出了一些保护对策,并建议把五岭过路黄等32种植物列为保护植物。 相似文献
929.
930.
以祥云水目山州级自然保护区及其外围2000 m缓冲区为研究对象,依据2005、2014、2019年Google Earth历史影像及相关调查数据,采用LDI评价方法,分析水目山生态环境健康状况在时间和空间上的变化特征。结果显示,研究区域土地利用类型中林地占63%以上,保护区林地占97%以上,是以林地为主、农地为辅的山地农林复合生态环境。受农业生产、居住环境建设、公共基础建设、旅游业发展等人类活动的影响,研究区域景观破碎度及多样性指数在时空尺度上存在不同程度及不同趋势的变化。2019年研究区域的LDI综合指数为3.04,生态环境健康等级为“一般”;保护区的LDI综合指数在该时间段为1.91,生态环境健康等级处于“健康”等级,随时间的推移,有向“一般”等级发展的趋势。 相似文献