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1.
Cities around the world are investing in urban forest plantings as a form of green infrastructure. The aim is that these plantations will develop into naturally-regenerating native forest stands. However, woody plant recruitment is often cited as the most limiting factor to creating self-sustaining urban forests. As such, there is interest in site treatments that promote recruitment of native woody species and simultaneously suppress woody non-native recruitment. We tested how three, common site treatments—compost, nurse shrubs, and tree species composition (six-species vs. two-species)—affected woody plant recruitment in 54 experimental plots beneath a large-scale tree planting within a high-traffic urban park. We identified naturally regenerating seedling and sapling species and measured their abundance six-years after the site was planted. This enabled us to examine initial recruitment dynamics (i.e. seedlings) and gain a better understanding of seedling success as they transition to the midstory (i.e. saplings). Seedling and sapling recruitment (native and total) was greater in areas with higher canopy cover. The combination of the nurse shrub treatment with compost and species composition (six-species) treatments increased seedling recruitment by 47% and 156%, respectively; however, the nurse shrub treatment by itself decreased seedling recruitment by 5% and native seedling recruitment by 35%. The compost treatment alone had no effect on the total number of recruits but resulted in 76% more non-native seedlings. The sizes of these treatment effects were strongly dependent on whether the forest plantings were in open areas, versus areas with existing tree canopy, the latter condition facilitating recruitment. Our findings therefore suggest that combinations of site treatments, paired with broad canopy tree species, may be most effective for promoting regeneration of native species resulting in more self-sustaining urban forests.  相似文献   
2.
The newly formed extensive flooded land associated with the Three Gorges Reservoir hold great potentials to provide ecosystem services (ESs) for surrounding cities and communities. Conflicting values and conventional management strategies may complicate and inhibit broad-scale decision-making for this novel ecosystem. Public attitudes are a crucial influence in the way this process plays out. This study was conducted to assess how the reservoir bank is perceived by the general public of Chongqing Municipality in terms of importance of riparian ESs, and preference for corresponding landscape design styles through photo-questionnaire interviewing. Although Chongqing citizens know little of the “ecosystem services” concept, they do recognise riparian environmental and ecological benefits especially the bank protection and pollution interception functions, while benefits of habitats for wildlife and flood attenuation were of less concern. Recreational values were least appreciated, which is inconsistent with other studies. This may be attributed to a wider, intensive environmental education in various social media in today’s China. But publicity has been dominated by toxic air, water and soil pollution control rather than the benefits of nature conservation and personal contact with nature. In line with recognition of ESs, there is quite strong preference for the forested design scenario and particularly vegetation components across the socio-demographic spectrum. Overall, socio-demographic variables have very low explanatory power for the perceptual responses. Our study also revealed misunderstandings around riparian functions and a gap between public expectations and special abiotic and biotic prerequisites in restoring novel ecosystems. Finally, we discuss the relevance of this research to urban novel ecosystems in general, and implications for raising public awareness, engaging appropriate public values in sustainable design and management of such ecosystems.  相似文献   
3.
呼和浩特市大气污染状况的研究及遥感信息的利用   总被引:1,自引:0,他引:1  
利用遥感技术结合地物波谱测定和叶表面内大气污染元素的含量测定分析研究大气污染是一种有效可靠的方法。克服了常规大气监测的弊病。充分显示了快速、准确的优越性。为城市规划和环境的综合治理提供了可靠的科学依据。  相似文献   
4.
通过介绍宁德市镜台山公园总体规划构思 ,论述在城市公园的规划中应遵循以人为本、尊重自然、尊重历史的规划方向 ;结合具有特色的自然山水、人文景观 ,运用各种造园方法 ,形成有序空间 ,实现生态、宗教、文化、娱乐、健身、休闲为一体的综合性功能和环境效益、社会效益、经济效益相统一的目标  相似文献   
5.
本文介绍了开发城市地下空间的必然趋势及前景,阐明开发利用城市地下空间,对节省城市用地、节约能源、改善城市交通、减轻城市污染等都有着重要作用。  相似文献   
6.
2004年冬成都市外来园林植物冻害调查及建议   总被引:7,自引:0,他引:7  
作者2005年春调查了成都市外来园林植物冻害情况,发现:(1)外来园林植物受冻害影响较为普遍,41种植物在不同程度上受害;(2)冻害影响存在区域差异,郊区冻害比城区严重.分析了冻害原因,并对园林植物引种提出建议.  相似文献   
7.
论西部大开发中张掖市生态环境建设问题   总被引:3,自引:0,他引:3  
张掖市长期受干旱、大风及沙尘暴影响,生态环境极为恶劣,制约着西部大开发建设进程。其存在的重要问题是:水资源匮乏,植被破坏严重,覆盖率低等;针对具体情况提出:改善水资源条件和恢复植被是张掖地区生态环境建设的重点。  相似文献   
8.
金昌水资源特点及供需平衡研究   总被引:3,自引:0,他引:3  
本文通过建立金昌市人口与牲畜增长规律 ,第二、三产业的GDP增长率规律数学模型 ,计算出在长时间序列中的用水量持续增长状况及根据金昌市农业节水技术和城市生态规划 ,得到农业、生态用水量规划数据。根据水量平衡原理 ,分析了金昌市未来水量供需平衡问题 ,对指导金昌水资源利用 ,具有一定的现实意义。  相似文献   
9.
通辽市主要有五大水系,湿地面积广阔。近年来由于人口的增加和社会经济的发 展,对湿地破坏严重,使得湿地面积锐减,湿地功能下降,湿地生态环境恶化。文章运用了遥 感、GIS技术对通辽市湿地进行分析研究,简略提出其保护措施。  相似文献   
10.
通过野外调查和查阅文献资料,得出石门国家森林公园共有野生观赏植物122科267属377种,其中蕨类植物19科23属28种,裸子植物4科5属7种,被子植物99科239属342种。分析了石门国家森林公园野生观赏植物资源的基本特征和用途,并探讨其保护和开发利用。  相似文献   
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