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1.
This article investigates the impact of natural burial on the delivery of ecosystem services (ESs) in urban cemeteries in England that are owned and managed by local authorities. Local authority natural burial sites have received far less attention from researchers than independent sites developed by farmers, charitable trusts, funeral directors and land owners. Here we argue that the local authority hybrid cemeteries that combine natural burial with traditional graves may have a far greater impact in delivering regulatory and cultural ecosystem services than the much larger and frequently more environmentally ambitious natural burial grounds developed by the independent sector. The article presents three case studies of cemeteries, each of which represents a different interpretation of natural burial. Two have retrofitted natural burial into an existing cemetery landscape. The third is a new cemetery where natural burial was included with traditional burial in the original design brief and planning application. The research reveals how natural burial is transforming the traditional cemetery, with its focus on an intensively managed lawn aesthetic, towards a more habitat rich and spatially complex landscape with its own distinctive identity. The research also reveals how natural burial (within the unique constraints of UK burial culture that does not permit the recycling of burial space) is increasing the burial capacity of urban cemeteries by accessing land and grave space that might not be suitable or appropriate for more traditional forms of burial.  相似文献   

2.
City edges have been associated with waste and wastelands for centuries. Refuse dumps have frequently been located at the outskirts of the city, and the metaphor of ‘wasteland’ has been used to depict landscapes at the urban fringe. In this paper, the relationship between actual waste dumps and metaphorical wastelands is brought forward to facilitate an analysis of landscape transformations at the city edge and to reveal the neglect of transient landscapes within spatial planning. In the first part of the paper the interactions between dumps and ‘wastelands’ at the city edge are discussed. In the second part, a case study at the edge of Malmö (in southern Sweden) is presented as an illustration of the transformative city edge and in particular the invisibility of this landscape in local planning. Major landscape transformations during the 20th century are examined along with representations of the area within spatial planning. The primary sources of information have been the archives of the local and regional waste management divisions, local planning documents and field studies. The case study illustrates how the present fringe landscape is constantly camouflaged by a green future; it is always about to be transformed, and therefore ignored. Consequently, an everyday landscape, with hazardous waste as well as places of great potential for recreation, has been disregarded for decades. The paper concludes with a discussion emphasising the importance to unveil such utopian representations, and the need to highlight the present day situation at the city edge.  相似文献   

3.
Chestnut stands (orchards and coppices) are among the most typical elements of the southern European mountain landscape and a protected habitat (9260 Castanea sativa woods) according to the European Union (Directive 92/43/EEC). As an anthropogenic landscape, they require specific measures to address preservation or to guide their evolutionary trend. In the Northern Apennines, a landscape multiscalar-multitemporal approach was adopted to highlight factors that have acted on the evolution of this habitat and which still might affect either its preservation or its evolutionary dynamics. Using a diachronic GIS-approach, we analyzed old cadastral maps (drawn up 200 years ago), and aerial photographs. Both the present distribution pattern of the woody species and the incidence of important chestnut diseases were also surveyed. The factors explaining the current extent and species composition of the local chestnut forests confirm their status as an anthropogenic habitat. The present landscape distribution of chestnut woods is heavily linked to past human settlements. Chestnut blight and ink disease are more an indirect reason for past felling activities than an actual direct cause of damage to trees, because of the hypovirulence spread and the limited incidence of the ink disease. Vegetation dynamics of abandoned chestnut forests evolved only partly towards deciduous Beech and Hop Hornbeam stands, thus suggesting both the possibility of a recovery of this cultivation and the need for new criteria for its management.  相似文献   

4.
5.
Summary

Four N application rates generated a range of tree N status as indicated by leaf N concentrations in six year old trees of `Mission' almond (Prunus dulcis (Mill.) D. A. Webb). Leaf N concentrations were related positively with concentrations of amino acids - especially asparagine and glutamine - in phloem and xylem saps. A pulse of 1.25 kg N per tree was applied to trees previously receiving 0, 78, 157 or 313 g N per tree, annually. Apparent uptake of soil N into above-ground tree parts was determined over a 39 d period. N uptake was determined as the difference in the products of tree biomass and tissue N concentrations before and after the N pulse. Tissue N concentrations increased signi®cantly in trees previously receiving the two lowest N application rates, whereas trees previously receiving the high N treatments were unresponsive. Tree N contents (0 g N per year, and also 78 g N per year treatments) increased slightly in response to the N pulse, although statistical differences were not observed due possibly to high variability in biomass among trees. At the same time, the amino acid concentrations in phloem exudate and xylem sap were highest in trees grown under the highest N fertilization regime. We suggest that the high amino acid concentrations in the phloem and xylem saps are indicative of a larger pool of amino N cycling throughout the vasculature of high N-status trees. Our data indicate an inverse relationship between tree N status, amino acid concentrations in xylem and phloem saps and capacity for soil N uptake in ®eld-grown trees. These results represent the ®rst ®eld data to correlate the concentration of amino acids circulating in the plant vasculature with soil N uptake. A functional relationship between the amino acid concentrations cycling within the tree and the regulation of soil N uptake has, however, not yet been established.  相似文献   

6.
The metacommunity concept provides a spatial perspective on community dynamics, and the landscape provides the physical template for a metacommunity. Several aspects of landscape heterogeneity, such as landscape diversity and composition, and characteristics of the matrix between habitat patches such as habitat connectivity, and geometry of habitat patches, may moderate metacommunity processes. These aspects of landscape heterogeneity are rarely considered explicitly in the metacommunity discussion, however. We propose landscape contrast (i.e., the average dissimilarity in habitat quality between neighboring patches) as a key dimension of landscape heterogeneity. The concept of landscape contrast unifies discrete and continuous landscape representations (homogeneous, gradient, mosaic and binary) and offers a means to integrate landscape heterogeneity in the metacommunity concept. Landscape contrast as perceived by the organisms affects several fundamental metacommunity processes and may thus constrain which metacommunity models may be observed. In a review of empirical metacommunity studies (n = 123), only 22 % of studies were explicit about their underlying landscape model assumptions, with striking differences among taxonomic groups. The assumed landscape model constrained, but did not determine, metacommunity models. Integration and explicit investigation of landscape contrast effects in metacommunity studies are likely to advance ecological theory and facilitate its application to real-world conservation problems.  相似文献   

7.
8.
There are sporadic reports on urban forests in Indian cities. Nagpur is one of the greenest cities of India with 18 per cent of its area under forests and plantations, 17 per cent under cultivation and 2 per cent under water bodies. The present study showed that natural vegetation of the city is very well diversified with a representation of 59 per cent vegetation including 124 trees species belonging to 38 families as compared with the overall district vegetation statistics. Air quality in the city is relatively better with lower SO2 (6 μg/m3), NO2 (18 μg/m3) and Respirable Suspended Particulate Matters (RSPM, 53 μg/m3) as against National Ambient Air Quality Standards (2009) for cities in India of 80, 80 and 100 μg/m3, respectively. It was also noted that the diversity in natural forests which are being protected is greater than the plantations undertaken by the civic authorities and private sector efforts. The study thus demonstrated the positive relationship of the city with diversified vegetation cover for cleaner environment. The analysis is expected to guide formulation of strategies for maintaining green space in the city.  相似文献   

9.
Nature-based solutions (NBS) can mitigate the challenges of climate change, biodiversity loss and mental wellbeing prioritised by the global Sustainable Development Goals (SDGs). The advantages of co-producing NBS with local communities have been explored, yet there is a lack of understanding of professional partners’ priorities in relation to specific projects, and their perceptions of the opportunities and challenges encountered during the co-productive process. The benefits of co-producing NBS with children are not understood, particularly in deprived, diverse communities. We addressed these gaps by conducting in-depth, semi-structured interviews with eight professional partners in contrasting roles involved in the co-production of an educational arboretum-meadow on a redundant mini-golf site in Wardown Park, within the High Town ward of Luton, Bedfordshire, UK. Here there is considerable ethnic diversity with 41% residents White British, and 59% other ethnicities. There are significant Black and Minority Ethnic communities (38%). A high percentage of households live with overcrowding (24%) and 31% year six children are obese. All partners prioritised connecting children to nature. The social benefits of the project were prioritised over ecological and climate-related ones. Most participants perceived diverse partner expertise and priorities as an opportunity of co-production. Covid-19 was considered a significant challenge and an opportunity. Our research provides insight into the potential for co-production of NBS in a relatively deprived, ethnically diverse context to contribute to “futureproofing” towns and cities by fostering nature connection amongst children, whilst providing a novel, creative approach to managing and maintaining GI under austerity. Learning from this project has international transferability as a ‘flagship project’ illustrating how the global Sustainable Development Goals (SDGs) can be addressed at the local level.  相似文献   

10.
Invasion ecology has made rapid progress in recent years through synergies with landscape ecology, niche theory, evolutionary ecology and the ecology of climate change. The palaeo-record of Holocene invasions provides a rich but presently underexploited resource in exploring the pattern and process of invasions through time. In this paper, examples from the palaeo-literature are used to illustrate the spread of species through time and space, also revealing how interactions between invader and invaded communities change over the course of an invasion. The main issues addressed are adaptation and plant migration, ecological and evolutionary interactions through time, disturbance history and the landscape ecology of invasive spread. We consider invasions as a continuous variable, which may be influenced by different environmental or ecological variables at different stages of the invasion process, and we use palaeoecological examples to describe how ecological interactions change over the course of an invasion. Finally, the use of palaeoecological information to inform the management of invasions for biodiversity conservation is discussed.  相似文献   

11.
12.

Context

Restoring or establishing corridors between residual forest patches is one of the most adopted strategies for the conservation of animal populations and ecosystem processes in fragmented landscapes.

Objectives

This study aimed to assess whether it is more effective to focus restoration actions on existing corridors or to establish habitats in other strategic areas that can create new dispersal pathways to enhance connectivity.

Methods

We considered a real agroecosystem in northern Italy, based our analyses on graph-theory and habitat availability metrics, and focused on the Hazel Dormouse as the target species. We compared the connectivity increase resulting from (i) the simulated restoration of existing priority corridors, i.e., those with significant presence of forest but in which restoration actions would still result in considerable connectivity gains, or (ii) the simulated plantation of 30 hedgerows along new priority pathways, i.e., those areas with no current forest cover in which habitat creation would be more beneficial for connectivity.

Results

Implementing new priority pathways resulted in substantially larger connectivity gains (+?38%) than when restoration efforts were concentrated in improving already existing corridors (+?11%).

Conclusions

Establishing hedgerows along new pathways allowed enhancing the complementary and functionality of the full set of landscape corridors and proved more efficient than just strengthening the areas where dispersal flows were already concentrated. We demonstrated the importance of analytical procedures able to compare the effectiveness of different management strategies for enhancing connectivity. Our approach may be applied to multiple species sensitive to fragmentation in other heterogeneous landscapes and geographical contexts.
  相似文献   

13.
Glasgow, Scotland, is embarking on an ambitious plan to convert all city centre thoroughfares into tree-lined streets (the ‘Avenues Programme’) to make the city centre more people-friendly, attractive, greener, sustainable and economically competitive. While it is well-known that urban green infrastructure (UGI) is a promising strategy to address overheating in urban areas, evidence for the surface temperature, air temperature and thermal comfort effects of street trees is contradictory. In the context of a city-centre-wide ‘Avenues Programme’ in Glasgow, we explore its co-benefits in terms of temperature and thermal comfort. We used a multi-method approach, combining GIS-based spatial analysis with fieldwork, microclimate modelling and statistical analysis to determine the scale of the overheating problem and the likely role of its mitigation based on the ‘Avenues Programme’ case study. We show that the Surface Urban Heat Island (SUHI) differences within the city are of the same magnitude as the urban-rural anomaly and “hot” spots are localized in the city centre area and are clustered in different patterns depending on the severity of background temperatures. Therefore, small, isolated patches of vegetation would not be effective for cooling the clusters of overheated areas. Air temperature showed non-linear relationship with tree canopy cover and the relationship is stronger at medium scale. The ‘Avenues Programme’ as a whole, could eliminate the UHI effect in the city centre, with some tree species completely eliminating the UHI in the city centre. Once complete, the ‘Avenues Programme’ could significantly improve thermal comfort during heatwaves from the current ‘hot’ category to ‘slightly warm’ across the city centre.  相似文献   

14.
Diversity in the urban forest is important as it reduces risks from pests and diseases and from climate change and improves resilience in the supply of ecosystem services. To manage and improve diversity, there has been wide-spread acceptance of the 10/20/30 ‘rule of thumb’ proposed by Santamour, which states that municipal forests should comprise no more than 10% of any particular species, 20% of any one genus or 30% of any single family. While the implementation of targets based on Santamour's rule has contributed to a more diverse and resilient urban forest in many cities, there has been little empirical investigation of actual patterns of diversity occurring globally in different climates and land uses. In this study, we explored diversity and the relative abundance of the most common species, genus and family in 151 urban forest inventories from 108 different cities around the world. Observed patterns showed that relative abundance of the most common taxon was a good predictor of diversity and could be a useful measure of diversity for urban forest managers. Relative abundance of the most common taxon was much higher than the proposed benchmark at the species level, but comparable with proposed benchmarks at the genus and family level. Patterns varied by both climate and land use. Diversity was consistently lower in Continental climates and in streetscapes, and higher in Temperate climates and in urban forests that spanned multiple land uses. Further considerations in setting diversity benchmarks are discussed.  相似文献   

15.

Context

Multi-scale approaches to habitat modeling have been shown to provide more accurate understanding and predictions of species-habitat associations. It remains however unexplored how spatial and temporal variations in habitat use may affect multi-scale habitat modeling.

Objectives

We aimed at assessing how seasonal and temporal differences in species habitat use and distribution impact operational scales, variable influence, habitat suitability spatial patterns, and performance of multi-scale models.

Methods

We evaluated the environmental factors driving brown bear habitat relationships in the Cantabrian Range (Spain) based on species presence records (ground observations) for the period 2000–2010, LiDAR data on forest structure, and seasonal estimates of foraging resources. We separately developed multi-scale habitat models for (i) each season (spring, summer, fall and winter) (ii) two sub-periods with different population status: 2000–2004 (with brown bear distribution restricted to the main population nuclei) and 2005–2010 (with expanding bear population and range); and (iii) the entire 2000–2010 period.

Results

Scales of effect remained considerably stable across seasonal and temporal variations, but not the influence of certain environmental variables. The predictive ability of multi-scale models was lower in the seasons or periods in which populations used larger areas and a broader variety of environmental conditions. Seasonal estimates of foraging resources, together with LiDAR data, appeared to improve the performance of multi-scale habitat models.

Conclusions

We highlight that the understanding of multi-scale behavioral responses of species to spatial patterns that continually shift over time may be essential to unravel habitat relationships and produce reliable estimates of species distributions.
  相似文献   

16.
The vegetation of the Wet Tropics bioregion of Far North Queensland is a complex system whose components (mainly tropical rainforests and fire-prone forests and woodlands) have mostly been studied independently from each other. We suggest that many characteristics of the vegetation are consistent with those of a complex, dynamic, spatially heterogeneous system which exhibits alternative stable states. We propose these states are driven and maintained by the interaction of vegetation-specific positive feedback loops with the regions’ environmental parameters (such as topography, steep humidity gradients and seasonality) and result in the rainforest/fire-prone vegetation mosaic that characterises the area. Given the regions’ magnitude, biodiversity and complexity, we propose the Wet Tropics as an important new example and a good testing ground for alternative stable state and resilience theories in large heterogeneous natural systems. At the same time, thinking in terms of alternative stable states and resilience creates a new context for understanding the regions’ biological dynamics.  相似文献   

17.
For a quarter of a century, sustainable development has been on the political and research agendas. Within the field of landscape ecology, a wide array of research has documented the effects of alternative land uses, analysed driving forces of land use change and developed tools for measuring such changes, to mention but a few developments. There have also been great advances in technology and data management. Nevertheless, unsustainable land use continues to occur and the science of landscape ecology has had less influence on landscape change than aimed for. In this paper we use Norwegian examples to discuss some of the reasons for this. We examine mismatches in the spatial and temporal scales considered by scientists, decision-makers and those who carry out land use change, consider how this and other factors hinder effective communication between scientists and practitioners, and urge for a stronger focus on what it is that motivates people to action. We suggest that the concept of landscape services can be useful not only for researchers but also provide valuable communication and planning tools. Finally, we suggest more emphasis on applying adaptive management in landscape ecology to help close the gaps, both between researchers and policy and, even more crucially, between researchers and practitioners.  相似文献   

18.
Genetic diversity studies were conducted to evaluate intra-specific relationships in Tunisian fig (Ficus: Moraceae) using sequences of the ITS regions of nuclear ribosomal DNA and the chloroplast non-coding region trnL–trnF (trnL intron, and trnL [UAA]–exon–trnF [GAA] intergenic spacer). All data sets suggest that the sequences obtained showed variations either on their lengths or on their nucleotide compositions. The mean size of these nuclear and cytoplasmic non-coding regions is 697.5 and 1035 base pairs for ITS and trnL–trnF chloroplast DNA, respectively. Our results suggest that the substitution rate estimated for the ITS sequences of nuclear DNA is greater than the one unregistered for the non-coding regions of chloroplast DNA. Therefore, chloroplast DNA shows more homoplasy than the nuclear ribosomal DNA. In fact, the consistency (CI) and retention (RI) indexes calculated for nuclear and cytoplasmic DNAs show values of 0.420 and 0.490 for chloroplast DNA and 0.573 and 0.387 for ribosomal DNA, respectively. The nuclear DNA has more resolution of genetic relationships between cultivars. In addition, the result suggests that the cultivars studied are clustered independently from their geographical origin and the male trees did not thoroughly diverge from the common figs. The discordance between chloroplast and the nuclear topology is revealed. The lack of congruence between the two data sets may be a result of hybridization or introgression. Our result showed that the nuclear and cytoplasmic sequences are useful for germplasm discrimination as well as for investigation of patterns of variation in fig.  相似文献   

19.
The efforts to mitigate CO2, one of the greenhouse gases causing global warming and climate change problems, have an important place in the worldwide agenda. One of the factors that cause CO2 emissions is energy use in residential buildings, hence urban residential use is one of the areas on which mitigation efforts are focused. As land use planning determines the spatial development, density and form of residential areas, it has a direct role in the formation of residential emissions. However, these efforts to mitigate emissions could not yet be integrated with land use planning. It is possible to list the reasons as the mitigation efforts are made either on the building scale (mitigation of residential emissions by technological–architectural solutions) or on a global–regional scale (development of carbon sinks), the focus on transportation sector, and in land use planning, lack of considering the potential of urban green areas to mitigate emissions. By taking into consideration the O2 production potential of green areas, a method proposal for land use planning is developed in this study to maintain the carbon–oxygen balance in residential areas. Depending on the form and density of the residential areas developed in a plan, the necessary size of green areas in such a plan is estimated by the method proposed. The varying emission amounts in different residential areas with diverse housing types, the number of actively used residential units, and local vegetation differences are included in the estimate. Therefore, an estimation method proposal that could be easily used in land use planning and that considers local differences is presented in the paper.  相似文献   

20.
The Dutch coastline is expected to change considerably during the next 100 years. Erosion will prevail, although accretion will occur locally.To establish a new policy for coastal defence management an integrated policy analysis study was performed. Major dune functions (nature conservation, recreation, public drinking water supply, housing and industry) have been inventarized by using a Geographic Information System.This study reports on the part of the analysis which takes nature conservation interests into account. Evaluation of nature interests has been based on the criteria: rarity and diversity of plant species c.q. vegetation types, succession stage, and completeness. This results in a classification of nature into five classes, based on abiotic as well as biotic characteristics of the landscape. Losses of nature interests were studied due to: loss of land because of shoreline retreat, to remodelling of the foredune ridge, and to changes of the dune groundwater level.An evaluation is given of the methods used to assess ecological impacts.Ideas are presented for further research on the prediction of ecological impacts and on coastline management which combines traditional coastal defence with nature conservation.  相似文献   

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