首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Globally, biodiversity offsetting is used to balance negative impacts on biodiversity and ecosystem services caused by exploitation. In Sweden, there is an increasing interest in biodiversity offsetting in urban planning. However, there is limited understanding about the use of the concept in a municipal context. This study aims to examine and critically reflect on the uptake and use of biodiversity offsetting at a strategic level in urban planning in Sweden. We study urban planning documents, and included Sweden’s 290 municipalities in the study. The result shows that more than 50% of Sweden’s municipalities mention biodiversity offsetting in their planning documents, targeting both regulatory offsetting of protected areas and voluntary offsetting of urban green space. The uptake is highest in urban areas experiencing high exploitation pressure, and many municipalities include both biodiversity and ecosystem services in their strategic work with offsetting. Most municipalities do not relate to the mitigation hierarchy (avoid, minimize, restore, offset), nor the goal of no net loss of biodiversity and ecosystem services. There is an ambiguity in the translation between losses and offsets, i.e. what type of offsetting (like-for-(un)like), what replacement ratios, and where to place the offsets. Few municipalities have developed processes, guidelines, strategic plans, etc., to integrate offsetting into the planning process. We conclude that the uptake of biodiversity offsetting is substantial, but with a fragmented, and often immature use in relation to ecological knowledge, and the planning process. We argue that, to develop biodiversity offsetting into an approach that delivers sound outcomes for nature and people in urban planning, municipalities must have a capacity in terms of organisational structures and resources.  相似文献   

2.
3.
4.
5.
Studies have pointed at the negative side of urban green spaces in terms of evoking fear of crime. However research on fear-provoking attributes suggests that there usually is no single attribute that influences fear but that rather a combination of attributes prevails. The aim of the paper is to systematically review those attributes that evoke fear of crime in urban green spaces and to highlight their complex interaction by adopting a social-ecological framework. Results include an overview of the reviewed literature with regard to authorship, journal, geographical distribution of the studies, types of urban green spaces studies, types of landscape stimulus used, applied methods, types of respondents involved and main study findings. Forty-eight studies met the authors’ inclusion criteria. The majority of the studies highlighted that individual factors (such as gender and past experience) were more influential than social and physical factors in evoking fear of crime. A proposed socio-ecological framework highlights the attributes which evoke fear of crime in urban green spaces and its interactions and can help guide future research.  相似文献   

6.
Frank  Karin  Wissel  Christian 《Landscape Ecology》1998,13(6):363-379
The role of spatial configuration for metapopulation survival is analyzed by using a stochastic metapopulation model. This model reveals conditions which must be satisfied by the species' ecology and the landscape settings before a metapopulation can persist over a long term. Taking this as a basis, initial rules of thumb for landscape management are deduced. The following results are highlighted: (1) the critical correlation length dc of the extinction processes determines a spatial scale of the metapopulation dynamics. (2) Only species with a dispersal range dr above the correlation length dc are able to benefit from landscape management at all. (3) A certain metapopulation can only persist over a long term if no patch is inside the range of correlation of another one. (4) There is a hierarchy of importance in the characteristics of a spatial configuration (scale and type) and, hence, in the scopes of landscape management. To conclude, some general consequences for supporting species survival by management are discussed. Some prospects concerning the use of models for decision support in landscape planning are discussed.  相似文献   

7.
The present study focuses on small urban public parks, specifically on how they should be designed to promote a potential for psychological restoration and on what activities people could imagine doing in such parks. Students from Oslo University College were presented with visual stimuli depicting 74 small urban parks. They were asked to assess how likely it was that they could rest and recover in the parks presented in the photos. In addition, the participants were asked to write down what park components contributed to high versus low ratings on restoration likelihood, and what types of activities they could imagine doing in the parks presented in the photos. The components and activities the participants mentioned were grouped into categories describing similar properties. The categories mentioned most frequently and giving high ratings on restoration likelihood represented natural categories such as: ‘a lot of grass’, ‘a lot of flowers/plants’ and ‘water features’. In contrast, the categories contributing to low ratings on restoration likelihood represented lack of vegetation or disturbance from the surroundings such as: ‘a lot of hard surfaces’, ‘a lot of traffic’ and ‘poorly shielded from the surroundings’. The activities mentioned as being typically performed in the types of parks presented in the photos were ‘relax and philosophize’, ‘read’ and ‘eat/drink’. Conclusions drawn from the study: Small urban parks should be designed with natural components, shielded from disturbing surroundings and furnished with some seating to promote opportunities for restorative experiences and to function as social meeting places.  相似文献   

8.
Data mining is used as a popular technique in several scientific researches. In agriculture, application of data mining is a relatively new approach. One of the most popular data mining approaches is to find prediction rules from experimental data sets. The present study was conducted in two stages to find out a rule for estimation of width of stalk cavity, depth of stalk cavity, width of eye basin and depth of eye basin of different apple varieties (‘Amasya’, ‘Starking’, ‘Granny Smith’, ‘Pink Lady’, ‘Golden Delicious’ and ‘Arapk?z?’) based on physical properties and to propose an equation for calculating these parameters. In the first stage, data processing was performed and in the second stage, Find Laws was used for prediction of apple properties. Current results revealed that data mining technique had a superior performance and could reliably be used in estimation of physical characteristics of agricultural products. Further research is recommended for possible use of datamining in other agricultural application.  相似文献   

9.
Trees in urban areas are pruned for several reasons. Each pruning cut causes a wound, which leads at least in the exposed wood at the wound surface to discoloration and decay. The extension of the resulting defect depends on wound diameter, tree species, time of wounding, wound treatment, and last but not least the attachment of the branch to the stem. The effects of different pruning cuts on urban trees has been investigated in Hamburg, Germany, since 1985. The study of 750 different pruning wounds on typical urban tree species lead to the Hamburg Tree Pruning System (Hamburger Schnittmethode). The system is described in this paper and answers the following questions: How should branches with and without a branch collar be removed? How should dead branches be removed? How should branches with included bark or codominant stems be removed? What are the differences between tree species in wound response? What is the maximum wound size which will be effectively compartmentalised by the tree?  相似文献   

10.
We report the successful micropropagation of a critically endangered medicinal plant Aconitum heterophyllum Wall., using low concentrations of plant growth regulators (PGRs) and molecular validation of the clonal stocks. The maximum rate of in vitro shoot multiplication was obtained on 1.0 × Murashige and Skoog (MS) medium containing 0.25 mg L?1 Kinetin (Kn) plus 0.25 mg L?1 Indole acetic acid (IAA). Up to 100% rooting was obtained 15 for shoots cultured on 1.0 × MS medium supplemented with 1.0 mg L?1 IAA. Adding 0.25 mg L?1 2,4-dichlorophenoxyacetic acid (2, 4-D) to 1.0 × MS medium resulted in 100% callus formation, while adding 0.25 mg L?1 IAA plus 0.25 mg L?1 Kn to 1.0 × MS medium containing 0.25 mg L?1 2,4-D resulted in 100% generation of embryogenic callus. Inter-simple sequence repeat (ISSR) marker analysis was carried out to check for possible somaclonal variation in the plantlets obtained after three consecutive sub-cultures. Of the 15 ISSR primers used, 10 were found to be monomorphic, with 95–98% similarity, and were used for cluster analysis by the unweighted pair group using arithmetic averages (UPGMA) method. The results revealed that in vitro-regenerated plantlets did not exhibit any genetic polymorphism.  相似文献   

11.
The importance of ecosystem services for human well-being has been highlighted by several recent environmental studies and assessments. These assessments provide useful information for urban green management, but they largely exclude various nuisances and losses produced by ecosystem functions. Lack of attention to these ecosystem disservices may seriously hamper environmental management in general and urban green management in particular. Ecological, social and technological changes will affect both what kind of disservices will emerge and how they will be experienced and managed. Especially in urban areas, environmental, social and technological changes spanning from global to local levels are continuously altering urban ecosystems. Our ways of perceiving and valuing ecosystem functions are also undergoing rapid change. Here we discuss the concept of ecosystem disservices from the perspective of northern European urban ecosystems. It is concluded that perceptions about ecosystem disservices have an increasing influence on how urban green areas are experienced, valued, used, managed and developed.  相似文献   

12.
Worldwide migration and integration are current issues facing big cities. Immigrants and their descendants represent an important percentage of today's urban populations. Different policies ranging from labour markets to education, housing or health policies address the specific needs of this part of society. However, public policy and planning concepts related to urban forests rarely focus on immigrants. Very few studies investigate the recreation patterns of immigrants despite the potential influence of their different cultural backgrounds on their perceptions or preferences regarding urban woodlands. In addition, urban woodlands could potentially play a role in the social integration of migrants into the society due to being an element of nature with a strong symbolic identification potential and also a public space for social interactions. This paper discusses the results of a qualitative enquiry carried out in Freiburg, Germany, involving migrants from Turkey, the Balkan countries and Russia-Germans. The results point towards many differences in their recreational use patterns and their perception of urban forests, especially between the Turkish interviewees and the other two groups. Furthermore, the results suggest that the emotional attachment to forests can play diverse roles in the identification process of immigrants to their host country. Finally, social interactions were depicted in the interviews as being an important aspect of a forest visit. Nevertheless, social contact between forest visitors seemed to remain mostly on a ‘small-talk’ level.  相似文献   

13.
Fruit landscaping can be a helpful addition for the conservation of old fruit varieties in gene banks. Very important for this are a long-term security of the plantations, reliable definition of the varieties and documentation with scientific attention. Four management conceptions with a different intensity are possible:
  1. Nature conservation (natural biotope without regulations),
  2. Landscaping (without state promotion impossible),
  3. Fruit utilization for processing (needs sufficient cultivation and special marketing conceptions) and
  4. Clearing and new plantation of over aged trees.
Recommendation of varieties for new plantations with old cultivars for conservation and special using in landscaping needs the consideration of regional features and scientific results especially of resistance characteristics of the varieties.  相似文献   

14.
Increasing the use of urban green space has appeared on the political agenda, primarily because increased use is expected to improve the health and well-being of the urban population. Green space is contributing to restoring mental fatigue, serving as a resource for physical activity, reducing mortality and reducing the level of stress.However, knowledge and experience on how to implement this agenda are scarce. In this paper, we use a socio-ecological model as framework when studying influences on the use of respondents’ nearest urban green space in the Danish city of Odense. Data were obtained from a survey sent to 2500 randomly selected adult residents within the central part of the city. We tested the relative importance of different factors on the frequency of use of the nearest urban green space by using a multivariate logistic regression model. The results show that almost half of the respondents did not use their nearest green space the most. Whether or not respondent used their nearest green space most depends primarily on area size, distance to the area and factors that are likely to express a reduced mobility; old age, young children and poor health.If the nearest urban green space also is the most used green space, having a dog is the only factor that significantly increases the frequency of use. Further research is needed to determine what it is that makes people use an area more, if the basic conditions of a reasonable size (>5 ha) within a reasonable distance (<600 m) are fulfilled.  相似文献   

15.
The 2nd World Congress on Biostimulants in Agriculture in Florence, Italy in November 2015 attracted ca. 1,200 participants with many attendees from the US, India, Asia and Brazil. The vendor section was dominated by ca. 14 mostly medium-sized Italian companies, their products and projects. The congress featured a number of molecular biology talks on gene up and down-regulation using mostly Arabidopsis, which seemed fairly unsuitable to an audience of agronomists.  相似文献   

16.
17.
We investigated the stand structure of ten young urban woodlands established in Southern Scandinavia during the 1970s and 1980s according to the ecological approach, which advocated the use of many different species of trees and shrubs to create complex canopy structures as soon as possible after establishment to promote recreation and biodiversity. Tree height and live crown depths were measured and analysed using a combination of quantitative and qualitative approaches to assess the forest structure in terms of canopy stratification. The results show that the current canopy structures could be classified into seven different two- and three-layered structural types which had evolved as a combination of differences in management frequency and the initial species composition. Two layered stands were characterized by lower management frequency compared to three layered stands and stands in transition to three layers. They were also established with a lower proportion of understory species and a higher proportion of shade tree species. The total number of species at the establishment did not influence how stands were categorized. The two main conclusions are that recurrent thinnings is a key factor for successful management of young, species rich forest plantations, and that species composition can increase the resilience towards management neglect. Instead of aiming at maximising total species number it is more reasonable to focus on a few key species in each layer. We conclude that three-layered canopy structures can be created already after twenty five years, which should encourage planners and practitioners to incorporate multilayered stands in future urban woodland creation.  相似文献   

18.
Hunziker  Marcel  Kienast  Felix 《Landscape Ecology》1999,14(2):161-176
As a result of the liberalisation of the agricultural market, mountain regions in Central Europe are at great risk of experiencing increasing land abandonment and spontaneous reforestation. Prior to taking measures for landscape maintenance, the ecological and landscape-aesthetic consequences of land abandonment should be analysed. This paper addresses the aesthetic component of such analyses: we investigated whether lay people perceive land abandonment and spontaneous reforestation as a loss or a gain and developed a prototypical technique for rapid aesthetic assessment of reforestation scenarios for vast regions.First, we conducted image experiments to assess the respondents' reactions to increasing levels of reforestation. Based on these experiments we concluded that a medium degree of reforestation is most desirable. Second, we analysed the relationship between scenic beauty and landscape patterns and found that landscape preference values correlate significantly with various quantitative measures of the landscape pattern (e.g., diversity and contagion indices of grey- tone and colour images). Third, we applied a GIS-assisted moving- window technique to transform spatially explicit remote-sensing data (in particular orthophotos) of a test region to spatially explicit data of landscape-pattern indices. Thanks to the significant positive correlation between pattern indices and landscape preference values, the resulting maps can preliminarily be interpreted as beauty-maps of the test-region.  相似文献   

19.
This case study describes a method for utilizing leaf-off airborne laser scanning (ALS) data for mapping characteristics of urban trees. ALS data were utilized to detect and update all street trees in the tree inventory of the City of Helsinki, Finland. The inventory consists of roughly 20,000 street trees with mean diameter at breast height (DBH) of 24 cm and mean height of 10.6 m. The large number of trees makes the manual updating process very laborious. The automatic mapping procedure presented in this paper detected 88.8% of all trees in the inventory. Tree height was predicted with root mean square error (RMSE) of 1.27 meters and tree DBH with RMSE of 6.9 cm. The presented method provides a practical and cost–effective tool for the mapping of urban tree characteristics. The cost–efficiency was further enhanced because the used ALS data were originally collected for other urban planning purposes.  相似文献   

20.
Understanding how trees influence water movement in an urban landscape is important because in an ‘engineered xeriscape’ small changes in rainfall frequency or magnitude have significant implications to plant water availability and mortality at one extreme, and stormwater runoff and flooding at the other. This study relates direct measures of tree canopy interception and discusses their implication for catchment hydrology in different urban landscape contexts. We measured canopy throughfall and stemflow under two eucalypt tree species in an urban street setting over a continuous five month period. Eucalyptus nicholii has a dense canopy and rough bark, whereas Eucalyptus saligna has a less-dense canopy and smooth bark. E. nicholii, with the greater plant area index, intercepted more of the smaller rainfall events, such that 44% of annual rainfall was intercepted as compared to 29% for the less dense E. saligna canopy (2010). Stemflow was less in amount and frequency for the rough barked E. nicholii as compared to the smooth barked E. saligna. However, annual estimates of stemflow to the ground surface for even the smooth barked E. saligna would only offset approximately 10 mm of the 200 mm intercepted by its canopy (2010).Tree canopy and bark characteristics should be considered when planting in pervious green space, or impervious streetscapes, because of their profound impact upon tree and surrounding water availability, soil water recharge or runoff. This study provides an evidence base for tree canopy impacts upon urban catchment hydrology, and suggests that rainfall and runoff reductions of up to 20% are quite possible in impervious streetscapes. Street tree canopies can function as a cost-effective compliment to water sensitive urban design for stormwater reduction benefits.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号