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1.
Improving green development efficiency is urgently required, yet challenging, since it comprehensively reflects the bidirectional evolutionary relationship between regional development and resource and environmental consumption. The issue of regional green development efficiency has become a key topic; however, where the increase in efficiency originates and its spatial spillover effect remains unclear to date. Therefore, the spatial spillover effect of the green development efficiency of Shandong Province was quantified through the slack variable (SBM)-Undesirable and Spatial Durbin model. The green development efficiency showed clear spatial differentiation in Shandong Province. This was more obvious than the polarized development trend of the provincial capital circle that has Jinan at its core and the eastern coastal region with Qingdao at its core. Green development efficiency has a significant spatial spillover effect. The regression coefficient of the direct effect of the economic development level is positive. The regression coefficient of the indirect effect of the marketization level and government financial support level is negative. Science and technology played a positive role in the promotion of the green development efficiency of local and neighboring cities. This study contributes empirical evidence to the green development efficiency associated with regional development and resource and environment consumption of Shandong Province.  相似文献   
2.
Interest in planting urban food trees (UFTs) in public spaces is growing in popularity as a form of urban greening and a potential food source. Currently there is minimal research on the governance and policy aspects of integrating food trees into cities. To fill this gap, we investigated the characteristics of UFT site governance and how it compares to current urban forest governance. Semi-structured interviews were conducted with relevant municipal officials in Calgary, Edmonton, Toronto and Victoria about their perspectives and involvement with UFT sites in their city. A scan of policy documents was completed to supplement the interviews. The interviews were analyzed using a deductive coding framework based on the Policy Arrangement Approach. We found that key actors at the UFT sites were local organizations and site champions, with minimal municipal engagement. Most site resources provided by municipalities were in-kind. There are also basic knowledge gaps about how to care for UFTs. Currently municipal by-laws prohibit the harvesting and removal of plant material, and are at odds with the purpose of UFT sites, with few municipalities fully integrating UFTs in policies. The primary discussion around UFTs centre concerns for public health and safety, management, and use of public space with limited discussions of benefits. This research demonstrates the value of co-governance models to support UFTs, while a shift in focus from risks to benefits could encourage additional resources and policy integration. Further, including UFTs into policy would also support foraging and food tree maintenance in public spaces, and more fully reflect the plurality of urban forest engagement.  相似文献   
3.
In this paper the results of the first comprehensive study on perception of and satisfaction with urban forests and green space in seven Southeast European cities are presented. The aims of the paper are to analyse 1) citizen perceptions of the current state of urban forests and green space in their cities, 2) to what extent current urban forests and green space meet their needs and how this can be improved. A cross-sectional study was conducted by using a common face-to-face survey questionnaire. Respondents were selected based on census data though a stratified sampling procedure by taking into account age, gender and city district (n = 384 in each city). The results showed that citizens genuinely care for urban forests and green space in their cities, but are not satisfied with their current state. The respondents found issues related to misbehaviour of other users, the presence and quality of facilities, as well as the presence and quality of management or maintenance the most pressing. There were more statistically significant differences than similarities between cities. Socioeconomic variables explained perceptions only to some extent. Citizens were very supportive of educational campaigns about the importance of urban forests and green space as well as of better enforcement of the existing regulations though having more community wardens that were expected to tackle current unsatisfactory situations. Urban planning and urban forest and green space management in these cities are facing many problems characteristic for post-socialist countries. Study findings are expected to contribute to decision making in urban planning and natural resource management.  相似文献   
4.
李霞 《绿色科技》2020,(3):197-200
对重庆市直辖以来的1997年、2002年、2007年、2012年的DMSP/OLS夜间灯光数据、有关旅游数据进行相关性研究,研究间隔周期为5年,结合使用GIS、SPSS软件进行了数据分析处理。研究结果表明:相关系数为0.99,说明重庆夜间灯光指数与有关旅游数据呈高度及显著的相关性,估算得到的旅游数据密度能够从一定层面反映重庆旅游发展状况的宏观分布现状,可为重庆市作出后期的旅游发展空间分布、相关决策等提供一定的参考。  相似文献   
5.
Determination of the threshold shear velocity is essential for predicting sand transport, dust release and desertification. In this study, a wind tunnel experiment was conducted to evaluate the influence of salinity and moisture on the threshold shear velocity of saline sand. Saline sand samples (mean particle size of 164.50-186.08 μm and the total silt, clay and salt content of 0.80%-8.25%) were collected from three saline sand dunes (one barchan dune and two linear dunes) in the Qarhan Desert, Qaidam Basin of China. Original saline sand samples were placed in two experimental trays for wet and dry processing to simulate deliquescence and desiccation, respectively. Surface moisture content ranging from 0.30% to 1.90% was generated by the steam method so that the saline sand can absorb water in a saturated water vapor environment. The motion of sand particles was determined by the observers with a solid laser. The laser sheet (0.80 cm thick), which was emitted by the solid laser, horizontally covered the sand surface and was bound to the sand. Results show that the cohesion of saline sand results from a combination of salt and water. The threshold shear velocity increases exponentially with the increase in crust thickness for the linear sand dunes. There is a positive linear correlation between the original moisture content and relative threshold shear velocity. The threshold shear velocity of dewatered sand is greater than that of wet sand with the same original moisture content. Our results will provide valuable information about the sand transport of highly saline soil in the desert.  相似文献   
6.
在分析江苏省流域管理现状及存在的问题基础上,对实施流域生态管理过程中涉及的若干问题研究,提出:①完善流域生态管理的政策支撑体系,要有相关法律法规制度保障、有完善的规划体系可执行;②改革流域管理体制,打破流域与行政区域的隔阂,建立江苏省流域委员会;③创新流域生态管理机制,建立流域安全机制、生态补偿机制、流域协作轴线、多参与流域决策系统和虚拟水战略等;④强化流域生态管理的技术支持,施行生态管理技术和数字流域建设等。  相似文献   
7.
乡村旅游经济系统与自然生态系统水乳交融,具有发展循环经济的天然条件.对昆明市西山区团结镇的实证研究表明:乡村旅游循环经济的模式主要有农家乐型、乡村休闲园型、观光农园型、采摘果园型、产品加工型、景区依托型、综合型等.  相似文献   
8.
Two hundred and fifty urban woody species are used in Central European parks and gardens. Based on reliable publications we attempt, for the first time, to extensively classify and assess them with regards to their usability after predicted climate changes. A new Climate-Species-Matrix has been developed for this purpose. In a two-dimensional assessment, four degrees of drought resistance and winter robustness are the decisive criteria. The woody species (divided into trees of more than 10 m in potential height and trees/shrubs of up to 10 m in height) were placed into 16 categories by decreasing tolerance, ranging from 1-1 (very suitable) to 4-4 (very limited usability). For many of these species, as well as many others that are not mentioned in this study, not all questions could be answered. Nonetheless, this categorization provides a sound basis for decisions in planning the use of woody species in cities. This planning process must also include additional criteria, dependent on individual requirements such as, soil parameters, shade resistance, aesthetics, etc. This paper is therefore meant to be a basis for discussion and supplementation for further research.  相似文献   
9.
南方岩溶区植被自然演替恢复研究综述   总被引:2,自引:0,他引:2  
我国岩溶区绝大部分分布在南方。植被的自然演替恢复是岩溶区生态重建的主要方式。随着自然演替的进行,土壤环境特征、土壤养分特征及土壤种子库等产生相应的变化。而岩溶植被的顶极群落特征和群落演替特征,包括盖度、结构、物种多样性、生物量、分布格局、演替方向都有其自身的特殊性。  相似文献   
10.
《林业研究》2020,31(4)
We evaluated the effects of the number of years of restoration of vegetation on soil microbial community structure and biomass in degraded ecosystems.We investigated the microbial community structure by analyzing their phospholipid fatty acids then examined microbial biomass carbon and nitrogen by chloroform fumigation extraction of restoration soils over several years.The data were compared with those of highly degraded lands and native vegetation sites.The results show that the duration of vegetation on the sites substantially increased microbial biomass and shifted the microbial community structure even after only 4 years.However,microbial communities and biomass did not recover to the status of native vegetation even after 35 years of vegetation cover.A redundancy analysis and Pearson correlation analysis indicated that soil organic carbon,total nitrogen,available potassium,soil water content,silt content and soil hardness explained 98.4% of total variability in the microbial community composition.Soil organic carbon,total nitrogen,available potassium and soil water content were positively correlated with microbial community structure and biomass,whereas,soil hardness and silt content were negatively related to microbial community structure and biomass.This study provides new insights into microbial community structure and biomass that influence organic carbon,nitrogen,phosphorus and potassium accumulation,and clay content in soils at different stages of restoration.  相似文献   
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