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41.
We examined the biodiversity of urban habitats in Birmingham (England) using a combination of field surveys of plants and carabid beetles, genetic studies of four species of butterflies, modelling the anthropochorous nature of the floral communities and spatially explicit modelling of selected mammal species. The aim of the project was to: (i) understand the ecological characteristics of the biota of cities model, (ii) examine the effects of habitat fragment size and connectivity upon the ecological diversity and individual species distributions, (iii) predict biodiversity in cities, and (iv) analyse the extent to which the flora and fauna utilise the 'urban greenways' both as wildlife corridors and as habitats in their own right. The results suggest that cities provide habitats for rich and diverse range of plants and animals, which occur sometimes in unlikely recombinant communities. The studies on carabids and butterflies illustrated the relative importance of habitat quality on individual sites as opposed to site location within the conurbation. This suggests that dispersal for most of our urban species is not a limiting factor in population persistence, although elements of the woodland carabid fauna did appear to have some geographical structuring. Theoretical models suggested that dormice and water voles may depend on linear habitats for dispersal. The models also indicated that other groups, such as small and medium sized mammals, may use corridors, although field-based research did not provide any evidence to suggest that plants or invertebrates use urban greenways for dispersal. This finding indicates the importance of identifying a target species or group of species for urban greenways intended as dispersal routeways rather than as habitat in their own right. Their importance for most groups is rather that greenways provide a chain of different habitats permeating the urban environment. We suggest that planners can have a positive impact on urban biodiversity by slowing the pace of redevelopment and by not hurrying to tidy up and redevelop brownfield sites.  相似文献   
42.
Effects of golf courses on local biodiversity   总被引:2,自引:2,他引:2  
R. A.  A. C.   《Landscape and urban planning》2005,71(2-4):137-146
There are approximately 2600 golf courses in the UK, occupying 0.7% of the total land cover. However, it is unknown whether these represent a significant resource, in terms of biodiversity conservation, or if they are significantly less diverse than the surrounding habitats.The diversity of vegetation (tree and herbaceous species) and three indicator taxa (birds, ground beetles (Coleoptera, Carabidae) and bumblebees (Hymenoptera, Apidae)) was studied on nine golf courses and nine adjacent habitats (from which the golf course had been created) in Surrey, UK. Two main objectives were addressed: (1) to determine if golf courses support a higher diversity of organisms than the farmland they frequently replace; (2) to examine whether biodiversity increases with the age of the golf course.Birds and both insect taxa showed higher species richness and higher abundance on the golf course habitat than in nearby farmland. While there was no difference in the diversity of herbaceous plant species, courses supported a greater diversity of tree species. Furthermore, bird diversity showed a positive relation with tree diversity for each habitat type. It was found that introduced tree species were more abundant on the older golf courses, showing that attitudes to nature conservation on courses have changed over time. Although the courses studied differed in age by up to 90 years, the age of the course had no effect on diversity, abundance or species richness for any of the animal taxa sampled. We conclude that golf courses of any age can enhance the local biodiversity of an area by providing a greater variety of habitats than intensively managed agricultural areas.  相似文献   
43.
Wilderness is a cultural construct that is deeply rooted in many societies. For landscape architects and their predecessors, wilderness has long been important as a contrast to artificial garden elements, as an inspiration for naturalistic plant designs, or today as a timely contribution to reconciling cities and their inhabitants with the natural world. Since cities and wilderness have traditionally been seen as opposites, new approaches are necessary to better address the opportunities and challenges associated with wilderness in urban regions. From an ecological perspective, urban wilderness can be defined as an area characterized by a high degree of self-regulation in ecosystem processes where direct human impact is negligible. This allows two main types of wilderness to be distinguished: “ancient wilderness” represented by natural remnants in many cities, and “novel wilderness,” which arises in artificial urban-industrial sites. The two types require different approaches in designing and managing green spaces. Ancient wilderness is a traditional object of conservation and restoration, and offers inspiration for naturalistic plantings. In contrast, the emergence of novel wilderness has long been associated with neglect and socio-economic decline. Since the 1980s, however, early pioneer projects in Germany have started to integrate novel urban wilderness into the green infrastructure. The results are unprecedented green spaces that combine novel wilderness with design interventions. These places are attractive to visitors, contribute to biodiversity conservation, and support many ecosystem services. This article aims to illustrate the opportunities and challenges of integrating wilderness components and processes into the urban green infrastructure—a timely way to reconnect cities with nature.  相似文献   
44.
The concrete channel of the Los Angeles (LA) River is probably one of the most recognizable rivers in the world. Channelized to manage the risk of flooding as the Los Angeles region urbanized, the river today is an architectural and engineering feat in the eyes of some people but an ecological disaster to others. The river flows adjacent to 17 cities and among some of the most environmentally burdened, park poor, and underserved communities of LA County. With over 2,300 acres of largely publicly owned land within the river right-of-way, a reimagined LA River can impact the lives of the one million people that live within a mile of the river. The LA River Master Plan, led by Los Angeles County and scheduled to be completed in fall 2021, proposes 51 miles of connected public open space with multi-benefit projects supporting nine goals ranging from flood resilience to housing affordability, to ecological function, and to arts, education, and culture. The data-based plan for the next 25 years includes a watershed-wide research effort to document and understand water quality, water conservation, and flood risk in relation to environmental and social issues. The plan includes traditional and innovative strategies within a “kit of parts,” interventions that include over 65 components ranging from habitat bridges to dry arroyo side channels demonstrating opportunities for enhancing ecosystem services to create a thriving urban habitat and connected network of parks along the river.  相似文献   
45.
Dark Matter, a research by design thesis, investigates the ecological value of human remains, and their latent agency for advancing biological diversity in urban cemeteries. The project proposes an expedited aboveground decomposition process (Natural Organic Reduction) to convert human tissue and bone into nutrient-rich soil-like materials. Following decomposition, human remains merge with non-human ecologies over time to offer mourners an extended period of ceremony and remembrance. Transference of energy and matter to adjacent non-human life is emphasized in the transition, and a memorial’s embodiment in physical space is expanded to include natural systems and ecological productivity. The funerary landscape is thus decentralized from a static site of memorial to an evolving memorial system that invites engagement with the living. In an age of pandemic, mass extinction, and deepening climate crises, a commitment to an environmentally ethical funeral practice connects the loss of the individual to global patterns of ecological ruin and environmental decline. These layered scales of grief are experienced at divergent timescales, suggesting the need for a new typology of memorial landscape that positions the human life within larger natural cycles of birth, death, decay, and metamorphosis. Rituals of commemoration, management, and activism would be alchemized to unexpected outcomes when the program of memorial, ecological preserve, and a theater for collective actions are merged. Dark Matter proposes a network of biodiverse public landscapes where bodily death events meaningfully contribute to ecological systems of propulsive regenerative life.  相似文献   
46.
The cultivation of bioenergy crops (BECs) represents a significant land-use change in agri-environments, but their deployment has raised important issues globally regarding possible impacts on biodiversity. Few studies however, have systematically examined the effect of commercial scale bioenergy plantations on biodiversity in agri-ecosystems. In this study we investigate how the abundance and diversity of two key components of farmland biodiversity (ground flora and winged invertebrates) varied between mature willow Short Rotation Coppice (SRC) and two alternative land-use options (arable crops and set-aside land). Although the abundance of winged invertebrates was similar across all land-uses, taxonomic composition varied markedly. Hymenoptera and large Hemiptera (>5 mm) were more abundant in willow SRC than in arable or set-aside. Similarly although plant species richness was greater in set-aside, our data show that willow SRC supports a different plant community to the other land-uses, being dominated by competitive perennial species such as Elytrigia repens and Urtica dioica. Our results suggest that under current management practices a mixed farming system incorporating willow SRC can benefit native farm-scale biodiversity. In particular the reduced disturbance in willow SRC allows the persistence of perennial plant species, potentially providing a stable refuge and food sources for invertebrates. In addition, increased Hymenoptera abundance in willow SRC could potentially have concomitant effects on ecosystem processes, as many members of this Order are important pollinators of crop plants or otherwise fulfil an important beneficial role as predators or parasites of crop pests.  相似文献   
47.
Freshwater biodiversity: a review of local and global threats   总被引:1,自引:0,他引:1  
The total freshwater biodiversity is not fully known. In particular, freshwater invertebrates and microbes are poorly studied groups, and in tropical latitudes, that support most of the species of the world, the information is lacking. Although almost a hundred thousand of species live in fresh water, the species losses continue at the high rate and the probability of preserving much of the remaining biodiversity in fresh water seems to be very low. Freshwater ecosystems are increasingly influenced by multiple stressors that lead to loss of sensitive species and an overall reduction in diversity. Environmental change threatens freshwater biodiversity. This paper reports an extensive review of work that evaluates the current main threats for freshwater biodiversity, on a local and global scale.  相似文献   
48.
Evidence on biopiracy of traditional knowledge and biodiversity is scarce. A method for generating evidence from patents was applied to a set of endemic plants used in Mexican Traditional Medicine. First the method identified a sample of patents as a potential source of evidence. Then, relevant arguments obtained from patents and traditional knowledge sources contributed to generate experimental evidence to sustain a possible case of biopiracy. The method's main implication is the possibility of identification of potential evidence on biopiracy by searching the global patent system.  相似文献   
49.
In recent years there has been a shift in biodiversity efforts from protected areas to one of interlinked habitat patches across multiple land tenure types. Much work remains on how managers can intervene in such systems to achieve basic goals. We use an agent-based model of a metapopulation with predator–prey dynamics and density-dependent migration to examine theoretically the capacity of a manager to modify the ecosystem to achieve conservation goals. We explore management strategies aimed at maintaining one of two goals – local or global coexistence of species. To achieve their goal, the manager varies the connectivity between patches based on one of three strategies – the monitoring of predator, prey, or the vegetation carrying capacity of the patches. We find that strategies that lead to highest coexistence monitor mid-tier populations globally. Our goal is to use our model results to advance decision-making in conservation beyond protected areas, typical in today's conservation.  相似文献   
50.
绿道理论的研究与应用具有鲜明的景观生态学基础,绿道规划倡导一种多尺度层级、多目标规划多学科综合的规划方法,在宏观的区域绿道网络规划到地方层面的绿道实践过程中,实现生态优先和以人为本的规划目标与生态保育的统一是珠三角绿道网规划贯穿始终的设计理念与出发点。广州和深圳绿道网络的规划与设计率先将绿道理论运用到建设实践中,是两个值得思考与借鉴的案例。  相似文献   
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