Classes of protection in urban forest fragments are effectiveless in structuring butterfly assemblages: landscape and forest structure are far better predictors

Urbanization is a major cause of biodiversity loss and disconnection between people and nature. For this reason, the creation and maintenance of green areas as part of the urban landscape is a common practice in cities around the world. These green areas are generally a result of particular public policies regarding how these areas can be accessed, maintained, and how they are connected to other natural fragments in the city. In an effort to investigate aspects of the ecology of such green areas of the city of Curitiba, southern Brazil, the present study measured distinct parameters of the structure of butterfly assemblages from 19 forest fragments of distinct classes of protection, testing the influence of different policies (protection category) on butterfly assemblages. Comparatively, we also tested the predictive power of landscape variables (at distinct scales) and fragment quality (e.g. diameter at breast height, density of vegetation) using Generalized Linear Models (GLMs). Overall, 14,596 individuals belonging to 412 butterfly species were recorded, but values of species diversity and composition are very heterogeneous, indicating that the protection categories do not significantly interfere with the structure of the butterfly assemblages. More important than the protection category is the forest fragment quality and landscape connectivity. Our models showed that degraded fragments tend to present a specific butterfly composition, whereas the more urbanized landscape have poor butterfly species richness. These results reinforce the importance of implementing public policies that prioritize the conservation of the quality of forest fragments in every class of protection, as well as the conservation of forest fragments throughout the urban landscape.

     

Effects of park size,peri-urban forest spillover,and environmental filtering on diversity,structure, and morphology of ant assemblages in urban park

Urban Ecosystems - Urban parks are likely the last green areas to preserve fauna diversity in urban ecosystems. We predicted that 1) species richness and ant diversity would increase with...     

Effects of habitat and landscape quality on amphibian assemblages of urban stormwater ponds

Urbanisation is one of the most severe drivers of current global biodiversity loss and has contributed to severe declines in many amphibian species. The aim of this study was to determine whether artificial stormwater ponds, designed to control water flow, can act as refuges for amphibians in urban areas. Moreover, we analysed the influence of habitat and landscape quality on amphibian species richness of 46 stormwater ponds (STOPON) in comparison to 46 control ponds (CONTROL).Our study revealed that environmental conditions clearly varied between STOPON and CONTROL. The most pronounced differences were that STOPON were larger, shallower, sunnier, more isolated by streets and had a greater cover of built-up area and lower cover of arable land surrounding them. Nevertheless, the amphibian assemblages of STOPON and CONTROL were very similar. All nine amphibian species (including three threatened species) detected in this study were found in both pond types. Moreover, species richness (2.8 ± 0.2 vs. 2.3 ± 0.2) and the frequency of each species did not differ between STOPON and CONTROL. The only exception was Pelophylax spp., which occurred more regularly in STOPON. Both habitat and landscape quality affected amphibian species richness; however, the explanatory power of the habitat models was about twice as high as those of the landscape models.In conclusion, stormwater ponds play an important role for amphibians in urban areas. In comparison to CONTROL, the low landscape quality in the surroundings of STOPON seemed to be compensated by a higher habitat quality due to regular management.     

Occurrence of breeding bird species in urban parks: Effects of park structure and broad-scale variables

Occurrences of breeding bird species in 54 urban parks were investigated in the city of Oulu in northern Finland. Park area, human activity, habitat, and landscape structure within a 9-ha square surrounding the study park were related to the bird species richness and occurrence of individual bird species. A total of 22 species was observed. The area of the park explained 39% of the variance of species richness. Seven species (wheatear [Oenanthe oenanthe], common rosefinch [Carpodacus erythrinus], garden warbler [Sylvia borin], lesser whitethroat [Sylvia curruca], linnet [Acanthis cannabina], redpoll [Carduelis flammea], and yellowhammer [Emberiza citrinella]) were not detected in parks of >0.75 ha. Species with lower area demands occurred closer to the town center than species with greater area requirements. Ground-nesting species were poor colonizers of urban parks, whereas high numbers of nest boxes in urban parks attracted many cavity-nesting species. The willow warbler (Phylloscopus trochilus) and the magpie (Pica pica) bred more often in unmanaged than in managed parks, probably because of the greater vegetation cover in unmanaged parks. Park structure variables were entered into models for 7 of the 12 most common bird species, whereas broad scale variables were entered into models for 6 of the 12 species. The number of adjacent buildings had a negative affect on three bird species (the willow warbler, hooded crow [Corvus corone cornix], and spotted flycatcher [Muscicapa striata]). The occurrence of breeding species in urban parks depends on the size of the park, park structure, and landscape structure outside the park.     

Local and landscape drivers of bird abundance,species richness,and trait composition in urban agroecosystems

Urban Ecosystems - Urban gardens, or spaces that include vegetables, fruit trees, and ornamental plants, can support bird species and communities by providing food and nesting habitat within urban...     

Influences of landscape structure on butterfly diversity in urban private gardens using a citizen science approach

Urban Ecosystems - Although urbanization is increasing worldwide, private gardens may help mitigate the impact of urbanization on butterfly diversity. We investigated how local and landscape...     

Coyote,fox, and bobcat response to anthropogenic and natural landscape features in a small urban area

Increasing urbanization across the southeastern United States presents unique challenges for wildlife; however certain species have learned to adapt and thrive in these environments. Coyotes (Canis latrans), bobcats (Lynx rufus), red foxes (Vulpes vulpes) and gray foxes (Urocyon cinereoargenteus) are four common medium-sized carnivores that have become closely associated with urban areas. The goal for this study was to determine how urban landscape features influence density and occurrence of these species in a small urban area and to evaluate if any effects were similar to those observed in larger urban areas. We conducted two eight-week camera surveys in the city of Nacogdoches, Texas (pop. 32,699) and immediate surrounding areas in summer and fall 2013. We evaluated single-season spatially explicit capture-recapture and occupancy models to estimate density, and occurrence, respectively, based on anthropogenic and natural features around each camera site. Coyotes (fall: 1.38 coyotes/km²) and bobcats (fall: 0.64 coyotes/km²) were associated with areas of green space, but their response to large and small green spaces changed seasonally. Conversely, red foxes (fall: 2.53 red foxes/km²) were more likely to occur near developed areas and were less detectable in areas with greater probability of coyote presence in fall only. In summer, gray foxes (fall: 0.05 gray foxes/km²) were more likely to occur in areas with lower building density and closer to buildings. This study indicates coyotes, foxes and bobcats respond to small-scale urbanization in a similar manner as large-scale urbanization.     

Native and exotic species in the urban landscape of the city of Rio de Janeiro,Brazil: density,richness, and arboreal deficit

Shaped by European influences, the Brazilian urban landscape was marked by the predominant use of exotic species in planted areas. In the 19th century along the city streets of Rio de Janeiro, trees were planted at a standard distance from each other. With time, native species began to be used in the urban landscape. Our purpose was to evaluate the utilization of exotic plant species in the urban landscape of Rio de Janeiro, evaluate the city’s arboreal deficit, and relate its neighborhood arboreal density to its economic index. Arboreal deficit represents the negative difference between the total number of expected trees and the observed number in the streets based in the standard distance used in the past. Twenty native and 40 exotic species were found in the 1701 streets sampled. A high percent of streets did not have any planted trees and the number of trees was greater in wealthier neighborhoods. The strong prevalence of exotic species is indicative of the negative impact of human activity on the biota. Since the municipality of Rio de Janeiro harbors forested areas, the risk for dissemination of exotic species is high.     

Spatial configurations of urban forest in different landscape and socio-political contexts: identifying patterns for green infrastructure planning

Rapid urbanisation and climate change have motivated the development of urban green infrastructure (UGI) as a planning strategy to support the wellbeing of urban people and ecosystems while parallel adapting cities to climate change. Forest (tree-covered areas >0.5 ha) is a key UGI component that afford a wider range of ecosystem services and mitigate urban heat islands more effectively than non-wooded green spaces. However, understanding of spatial configurations (variation in patch size and frequency) of forests across the gradient of urbanisation and between cities is limited to case studies. This represents a considerable knowledge gap for identification of general patterns that can inform integration of forest resources in UGI planning that have value beyond the individual city level. In this study we used Geographic Information Systems to explore the spatial configuration of forests across cities located within landscapes characterised by different levels of anthropogenic modification (degree of forest cover) and socio-political contexts, i.e. all Danish and Swedish cities >10,000 inhabitants (n = 176). We applied general linear modelling to investigate the relationship between forest cover, patch size and frequency with 1) regional landscape type, 2) demographic trends 1960–2010, and 3) the gradient of urbanisation (measured in three zones: urban core (0.2 km from city boundary), urban fringe (0.2–2 km), and urban periphery (2–5 km)). Regardless of demographic trends, forest cover was lowest in cities settled in large-scale agricultural regions, higher in regions with mosaics of forest and farming, and highest in forest-dominated regions. However, in all cities forest cover was lowest in the urban zone and peaked on the urban fringe rather than on the urban periphery. Furthermore, pocket woods (0.5–2 ha) accounted for over 50 % of patches in all three urban zones, irrespective of regional landscape type. We conclude by discussing how these general patterns could inform strategies for integration of urban forests in UGI planning.     

Characterizing air pollution patterns on multiple time scales in urban areas: a landscape ecological approach

Quantifying the spatiotemporal patterns of air pollution in urban areas is essential for studying ecological processes, environmental quality, and human health in cities. To adequately characterize or monitor air pollution patterns, one important issue is scale because the concentrations of air pollutants are temporally dynamic and spatially heterogeneous. Our research addresses the scale issue in air quality monitoring and analysis by considering the following research questions: (1) How does the spatial pattern of ozone change with the temporal scale of analysis? (2) How does the spatial pattern of PM₁₀ change with the temporal scale of analysis? (3) What implications do these scale effects have for designing and evaluating air pollution monitoring networks? We systematically examined these questions based on data from official air pollution monitoring networks in the Phoenix metropolitan region, Arizona, USA. Our results showed that spatial patterns of both ozone and PM₁₀ may change substantially with the temporal scale of analysis. Ozone patterns at broader (but not finer) temporal scales were more consistent across years, and exhibited a more uniform, regionalized pattern. PM₁₀ patterns were less consistent across years than ozone, and exhibited a more localized effect. Spatial patterns of PM₁₀ also varied seasonally. Our study demonstrates that it is critically important to consider the temporal and spatial scales in designing or evaluating air monitoring networks in particular and in conducting air pollution research in general.     

Determinants of urban tree canopy in residential neighborhoods: Household characteristics, urban form, and the geophysical landscape

The aesthetic, economic, and environmental benefits of urban trees are well recognized. Previous research has focused on understanding how a variety of social and environmental factors are related to urban vegetation. The aim is often to provide planners with information that will improve residential neighborhood design, or guide tree planting campaigns encouraging the cultivation of urban trees. In this paper we examine a broad range of factors we hypothesize are correlated to urban tree canopy heterogeneity in Salt Lake County, Utah. We use a multi-model inference approach to evaluate the relative contribution of these factors to observed heterogeneity in urban tree canopy cover, and discuss the implications of our analysis. An important contribution of this work is an explicit attempt to account for the confounding effect of neighborhood age in understanding the relationship between human and environmental factors, and urban tree canopy. We use regression analysis with interaction terms to assess the effects of 15 human and environmental variables on tree canopy abundance while holding neighborhood age constant. We demonstrate that neighborhood age is an influential covariate that affects how the human and environmental factors relate to the abundance of neighborhood tree canopy. For example, we demonstrate that in new neighborhoods a positive relationship exists between street density and residential tree canopy, but the relationship diminishes as the neighborhood ages. We conclude that to better understand the determinants of urban tree canopy in residential areas it is important to consider both human and environmental factors while accounting for neighborhood age.     

Place-based urban ecology: A century of park planning in Seattle

This research responds to calls from within the field of urban ecology to explicitly incorporate humanities-based research in order to achieve robust interdisciplinarity. Our research provides an example of a place-based urban ecological analysis. We use this framework to analyze over a century of park planning and development within the city of Seattle. We identify four eras of park planning that are linked by a comprehensive 100-year park plan. This case study examines how the political, cultural, and economic aspects of park planning have produced and been influenced by long-term trends and historical contingencies. This research also offers practical insights for effective contemporary urban planning, emphasizing the need for flexible and adaptive long-term plans when confronted with unpredictable events, emerging political arrangements, changing cultural priorities, and shifting fiscal climates.     

Habitat- and matrix-related differences in species diversity and trait richness of vascular plants,Orthoptera and Lepidoptera in an urban landscape

Urban growth is considered to be a major driver of environmental change. Urbanisation can affect urban biodiversity in different ways. So far, most studies focused on the impact of urbanisation on single taxa in one habitat type. In this study, we used data of species inventories and GIS-based landscape elements to examine the effects of habitat size and landscape composition on the species diversity of three taxonomic groups (vascular plants, Orthoptera and Lepidoptera) in meadows and ruderal sites in the urban region of Basel, Switzerland. We also related the responses of three species traits (body size, dispersal ability and food specialisation) to habitat size in Orthoptera and Lepidoptera. We found that species of the different taxonomic groups differed in their response to habitat size and landscape composition both in meadows and ruderal sites depending on the traits examined. The species richness of Orthoptera and Lepidoptera was positively related to meadow size but not to the size of ruderal sites, while the opposite was true for plants. For Lepidoptera in ruderal sites, the percentage cover of ruderal area in the closer surroundings was a better predictor of species richness than habitat size per se. To sustain high levels of urban biodiversity, we recommend that urban planners develop adequate management strategies to satisfy the different requirements of various taxonomic groups and to increase the quality of green sites surrounding the target habitat.     

Partitioning the effects of habitat fragmentation on rodent species richness in an urban landscape

Habitat fragmentation plays a major role in species extinction around the globe. Previous research has determined that species richness in fragments is affected by a number of characteristics. These include fragment age, size, and isolation, edge effects, vegetation coverage, habitat heterogeneity, and matrix content. Although most studies focused on one or a few of these characteristics, multiple characteristics work together to affect species richness, showing that the effects of habitat fragmentation are complex. The goal of our study was to partition the complex effects of habitat fragmentation by determining the direct, indirect, and cumulative effects of multiple habitat fragment characteristics on rodent species richness. In 2013, we determined rodent species richness in 25 habitat fragments within Thousand Oaks, California. In addition, we measured the following characteristics for each fragment: fragment age, area, isolation, shrub coverage, habitat heterogeneity, perimeter/area ratio, and percent non-urban buffer. Path Analysis was used to test the hypothesized model which described the direct, indirect, and cumulative effect of each habitat fragment characteristic on rodent species richness. Overall, the path model explained 67 % of the variation in rodent species richness among habitat fragments. Habitat heterogeneity had the greatest direct and total effect on rodent species richness. Fragment size had the next greatest total effect on rodent species richness but this was nearly entirely indirect through its influence on habitat heterogeneity, suggesting that large fragments containing the greatest diversity of habitats will support the most species. Our study shows that large habitat fragments support the greatest habitat diversity, which provides the highest likelihood of conserving rodent species richness in an urban landscape.     

Survival,abundance, and capture rate of eastern cottontail rabbits in an urban park

Eastern cottontail rabbits (Sylvilagus floridanus) are common, conspicuous denizens of urban environments. They are associated with human-wildlife conflict due to vegetation damage. Prior to this study, population dynamics of this species in urban environments remained largely uncharacterized. For three consecutive winters, we used classic field ecology methods (mark-recapture and mark–resight surveys) to estimate demographic parameters of rabbits in a city park in Chicago, Illinois. Rabbits occurred in densities as high as 16.3 rabbits/ha, which is comparatively high for the Midwestern United States. An annual survivorship of 30.4?±?12.9 % SE was similar to that observed in natural environments in similar climates. This result refuted our hypothesis that urban rabbits would have higher annual survival rates than rabbits in natural settings due to food subsidies supplied by landscaping in parks. Mean distance between trap locations for rabbits trapped three or more times was 43.14?±?30.01 m SD, suggesting that rabbits in the urban study area had smaller home ranges than rabbits in non-human-dominated habitats. This study contributes to our understanding of population dynamics of a human-wildlife conflict species in urban environments and provides useful information for managers dealing with damage caused by rabbits. The mark-resight method employed here could be used by managers to estimate pre- and post-management population sizes of other conflict species, for example Canada geese (Branta Canadensis), in parks and green spaces, provided that the species is trappable, visible, and individuals have relatively small home ranges.     

工业园区道路绿化景观改造的规划与建设--以天津经济技术开发区为例

一、工业园区景观的概念 工业园区是一种随着经济发展而产生的特殊空间类型,是为了在对内对外的经济活动中,实现特定的经济目标,而在特定范围内开辟的,实施特殊的经济政策和特殊的经济管理体制的经济性区域.爱尔兰香农机场是世界上第一个以引进外资发展加工工业为主的工业经济特区,截至目前,全世界已有各类工业园区近千个.     

Modeling urban landscape dynamics: A case study in Phoenix,USA

Urbanization has profoundly transformed many landscapes throughout the world, and the ecological consequences of this transformation are yet to be fully understood. To understand the ecology of urban systems, it is necessary to quantify the spatial and temporal patterns of urbanization, which often requires dynamic modeling and spatial analysis. In this paper, we describe an urban growth model, the Phoenix Urban Growth Model (PHX-UGM), illustrate a series of model calibration and evaluation methods, and present scenario-based simulation analyses of the future development patterns of the Phoenix metropolitan region. PHX-UGM is a spatially explicit urban landscape model and is a modified version of the Human-Induced Land Transformations (HILT) model originally developed for the San Francisco Bay Area. Using land use and other data collected for the Phoenix area, existing growth rules were selectively modified and new rules were added to help examine key ecological and social factors. We used multiple methods and a multi-scale approach for model calibration and evaluation. The results of the different evaluation methods showed that the model performed reasonably well at a certain range of spatial resolutions (120–480 m). When fine-scale data are available and when landscape structural details are desirable, the 120-m grain size should be used. However, at finer levels the noise and uncertainty in input data and the exponentially increased computational requirements would considerably reduce the usefulness and accuracy of the model. At the other extreme, model projections with too coarse a spatial resolution would be of little use at the local and regional scales. A series of scenario analyses suggest that the Metropolitan Phoenix area will soon be densely populated demographically and highly fragmented ecologically unless dramatic actions are to be taken soon to significantly slow down the population growth. Also, there will be an urban morphological threshold over which drastic changes in certain aspects of landscape pattern occur. Specifically, the scenarios indicate that, as large patches of open lands (including protected lands, parks and available desert lands) begin to break up, patch diversity declines due partly to the loss of agricultural lands, and the overall landscape shape complexity also decreases because of the predominance of urban lands. It seems that reaching such a threshold can be delayed, but not avoided, if the population in the Phoenix metropolitan region continues to grow. PHX-UGM can be used as a tool for exploring the outcome of different urban planning strategies, and the methods illustrated in this paper can be used for evaluating other urban models.     

Effects of urbanization on butterfly species richness,guild structure,and rarity

We evaluated the effects of landscape characteristics associated with urbanization, as well as local features, on butterfly species richness at four spatial scales (50, 150, 500, and 1,000 m from survey plots). We also evaluated these effects separately by butterfly guilds based on their region-wide rarity and on degree of specialization. The distribution of abundances of the 44 species observed showed an excess of uncommon species compared to a log-normal distribution, and the two most abundant species were exotic (Thymelicus lineola and Pieris rapae). We used an information theoretic approach to model selection to determine the most important correlates of butterfly species richness. Models of mean butterfly richness per visit explained greater variance than did models of cumulative richness across the season. Cumulative butterfly species richness was affected more at larger spatial scales, while richness per visit was affected similarly at all spatial scales. The most consistent local factor affecting butterfly diversity was the number of nectar producing plants that were flowering. The most consistent landscape-level correlates of species richness were number of people (at small spatial scales) and green space. Measures of increased urbanization were associated with decreased butterfly species richness, and rare and specialized species were most affected. Species that were regionally rare, and those that specialized both in host plants and had few broods, disappeared with declining richness across sites 2.9–4.5 times faster than did generalists and less restricted specialists.     

Composition and conservation value of bird assemblages of urban ‘habitat islands’: Do pedestrian traffic and landscape variables exert an influence?

Urban forest fragments can potentially be ‘habitat islands’ for native birds, but pedestrian traffic could influence the composition and conservation value of their bird assemblages by reducing the representation of disturbance-sensitive species. Winter bird assemblages and pedestrian traffic rates were documented in twelve forested parks in suburban Melbourne, Australia. Native birds comprised 87% of sightings, but two exotic species were common. Bird species' distribution among the parks was significantly nested. However, park rank orders for bird assemblage nestedness and mean pedestrian traffic rate were not correlated and only one species' distribution was nested with respect to this variable. The observed correlation between park area and bird assemblage nestedness may have been partly due to passive sampling. Degree of isolation of parks influenced nestedness less than park area. Forested parks provided habitat for species that occur at intermediate to low densities in other suburban habitats and for ecological specialists otherwise rare in suburbia. Larger parks contained more species than, and many of the native species found in, smaller parks. However, smaller parks each had 25% of the native bird species inhabiting the suite of fragments and thus had both aesthetic value and some potential to enhance city-dwellers' awareness about biodiversity conservation.