810 resultados para Protected landscapes
Resumo:
Urbanization is a global process contributing to the loss and fragmentation of natural habitats. Many studies have focused on the biological response of terrestrial taxa and habitats to urbanization. However, little is known regarding the consequences of urbanization on freshwater habitats, especially small lentic systems. In this study we examined aquatic macroinvertebrate diversity (family and species level) and variation in community composition between 240 urban and 782 non-urban ponds distributed across the UK. Contrary to predictions, urban ponds supported similar numbers of invertebrate species and families compared to non-urban ponds. Similar gamma diversity was found between the two groups at both family and species taxonomic levels. The biological communities of urban ponds were markedly different to those of non-urban ponds and the variability in urban pond community composition was greater than that in non-urban ponds, contrary to previous work showing homogenisation of communities in urban areas. Positive spatial autocorrelation was recorded for urban and non-urban ponds at 0-50 km (distance between pond study sites) and negative spatial autocorrelation was observed at 100-150 km, and was stronger in urban ponds in both cases. Ponds do not follow the same ecological patterns as terrestrial and lotic habitats (reduced taxonomic richness) in urban environments; in contrast they support high taxonomic richness and contribute significantly to regional faunal diversity. Individual cities are complex structural mosaics which evolve over long periods of time and are managed in diverse ways, promoting the development of a wide-range of environmental conditions and habitat niches in urban ponds which can promote greater heterogeneity between pond communities at larger scales. Ponds provide an opportunity for managers and environmental regulators to conserve and enhance freshwater biodiversity in urbanized landscapes whilst also facilitating key ecosystem services including storm water storage and water treatment.
Resumo:
Biodiversity loss is one of the most significant drivers of ecosystem change and is projected to continue at a rapid rate. While protected areas, such as national parks, are seen as important refuges for biodiversity, their effectiveness in stemming biodiversity decline has been questioned. Public agencies have a critical role in the governance of many such areas, but there are tensions between the need for these agencies to be more “adaptive” and their current operating environment. Our aim is to analyze how institutions enable or constrain capacity to conserve biodiversity in a globally significant cross-border network of protected areas, the Australian Alps. Using a novel conceptual framework for diagnosing biodiversity institutions, our research examined institutional adaptive capacity and more general capacity for conserving biodiversity. Several intertwined issues limit public agencies’ capacity to fulfill their conservation responsibilities. Narrowly defined accountability measures constrain adaptive capacity and divert attention away from addressing key biodiversity outcomes. Implications for learning were also evident, with protected area agencies demonstrating successful learning for on-ground issues but less success in applying this learning to deeper policy change. Poor capacity to buffer political and community influences in managing significant cross-border drivers of biodiversity decline signals poor fit with the institutional context and has implications for functional fit. While cooperative federalism provides potential benefits for buffering through diversity, it also means protected area agencies have restricted authority to address cross-border threats. Restrictions on staff authority and discretion, as public servants, have further implications for deploying capacity. This analysis, particularly the possibility of fostering “ambidexterity”—creatively responding to political pressures in a way that also achieves a desirable outcome for biodiversity conservation—is one promising way of building capacity to buffer both political influences and ecological pressures. The findings and the supporting analysis provide insight into how institutional capacity to conserve biodiversity can be enhanced in protected areas in Australia and elsewhere, especially those governed by public agencies and/or multiple organizations and across jurisdictions.
Resumo:
Although wildfire plays an important role in maintaining biodiversity in many ecosystems, fire management to protect human assets is often carried out by different agencies than those tasked for conserving biodiversity. In fact, fire risk reduction and biodiversity conservation are often viewed as competing objectives. Here we explored the role of management through private land conservation and asked whether we could identify private land acquisition strategies that fulfill the mutual objectives of biodiversity conservation and fire risk reduction, or whether the maximization of one objective comes at a detriment to the other. Using a fixed budget and number of homes slated for development, we simulated 20 years of housing growth under alternative conservation selection strategies, and then projected the mean risk of fires destroying structures and the area and configuration of important habitat types in San Diego County, California, USA. We found clear differences in both fire risk projections and biodiversity impacts based on the way conservation lands are prioritized for selection, but these differences were split between two distinct groupings. If no conservation lands were purchased, or if purchases were prioritized based on cost or likelihood of development, both the projected fire risk and biodiversity impacts were much higher than if conservation lands were purchased in areas with high fire hazard or high species richness. Thus, conserving land focused on either of the two objectives resulted in nearly equivalent mutual benefits for both. These benefits not only resulted from preventing development in sensitive areas, but they were also due to the different housing patterns and arrangements that occurred as development was displaced from those areas. Although biodiversity conflicts may still arise using other fire management strategies, this study shows that mutual objectives can be attained through land-use planning in this region. These results likely generalize to any place where high species richness overlaps with hazardous wildland vegetation.
Resumo:
The resilience of a social-ecological system is measured by its ability to retain core functionality when subjected to perturbation. Resilience is contextually dependent on the state of system components, the complex interactions among these components, and the timing, location, and magnitude of perturbations. The stability landscape concept provides a useful framework for considering resilience within the specified context of a particular social-ecological system but has proven difficult to operationalize. This difficulty stems largely from the complex, multidimensional nature of the systems of interest and uncertainty in system response. Agent-based models are an effective methodology for understanding how cross-scale processes within and across social and ecological domains contribute to overall system resilience. We present the results of a stylized model of agricultural land use in a small watershed that is typical of the Midwestern United States. The spatially explicit model couples land use, biophysical models, and economic drivers with an agent-based model to explore the effects of perturbations and policy adaptations on system outcomes. By applying the coupled modeling approach within the resilience and stability landscape frameworks, we (1) estimate the sensitivity of the system to context-specific perturbations, (2) determine potential outcomes of those perturbations, (3) identify possible alternative states within state space, (4) evaluate the resilience of system states, and (5) characterize changes in system-scale resilience brought on by changes in individual land use decisions.
Resumo:
Protected area downgrading, downsizing, and degazettement (PADDD) has been documented worldwide, but its impacts on biodiversity are poorly understood. To fill this knowledge gap, we reviewed historical documents to identify legal changes that altered the boundaries of Yosemite National Park. We identified two downsizes and five additions between 1905 and 1937 that reduced the size of Yosemite National Park by 30%. To examine the effects of these downsizing events on habitat fragmentation by roads, we compared protected, never-protected, and downsized lands at three spatial scales using four habitat fragmentation metrics: road density, fragment (land surrounded by roads) area-to-perimeter ratio, fragment area, and fragment density. In general, lands that were removed from protection, e.g., downsized, were more highly fragmented than protected lands and indistinguishable from never-protected lands. Lands where downsizes were reversed were less fragmented than lands where downsizes were not reversed. These results suggest that protected area downsizing may exacerbate habitat fragmentation, a key contributor to biodiversity loss globally. Furthermore, the case study in Yosemite National Park demonstrates that iconic protected areas in developed countries are not immune to downsizing. These findings underscore the need to account for PADDD and governance histories in ecological research, monitoring, and evaluation. As we move toward more evidence-based conservation policy, a rigorous understanding of PADDD is essential to ensure that protected areas fulfill their promise as a strategy for conserving global biodiversity.
Resumo:
The fisheries sector is vital to the Philippine economy, providing substantial employment and income, contributing export earnings, and meeting local food security and nutrition requirements. To protect coastal and marine habitat and to sustain fisheries, over 1000 marine protected areas (MPAs) have been established, in the Philippines. This paper provides empirical evidence on the variance of net revenues linked with MPA establishment and the possible range of relocation costs for fishing effort displaced by an MPA. A total of 424 households were randomly selected from 18 barangays (villages) adjacent to MPAs in three regions in the Philippines. Results show that incomes decrease significantly for both fulltime and seasonal types of fishers after 1-3 years of MPA establishment. The loss occurring through MPA is higher than expected and at least on the short run (up to 4 years) the spill-over effect does not compensate. This information helped to determine the necessary conditional cash transfers for coastal communities who are highly dependent on coastal and marine resources.
Resumo:
Can social inequality be seen imprinted in a forest landscape? We studied the relationship between land holding, land use, and inequality in a peasant community in the Peruvian Amazon where farmers practice swidden-fallow cultivation. Longitudinal data on land holding, land use, and land cover were gathered through field-level surveys (n = 316) and household interviews (n = 51) in 1994/1995 and 2007. Forest cover change between 1965 and 2007 was documented through interpretation of air photos and satellite imagery. We introduce the concept of “land use inequality” to capture differences across households in the distribution of forest fallowing and orchard raising as key land uses that affect household welfare and the sustainability of swidden-fallow agriculture. We find that land holding, land use, and forest cover distribution are correlated and that the forest today reflects social inequality a decade prior. Although initially land-poor households may catch up in terms of land holdings, their use and land cover remain impoverished. Differential land use investment through time links social inequality and forest cover. Implications are discussed for the study of forests as landscapes of inequality, the relationship between social inequality and forest composition, and the forest-poverty nexus.
Resumo:
A better understanding of the key ecological processes of marine organisms is fundamental to improving design and effective implementation of marine protected areas (MPAs) and marine biodiversity. The movement behavior of coral reef fish is a complex mechanism that is highly linked to species life-history traits, predation risk and food resources. We used passive acoustic telemetry to study monthly, daily and hourly movement patterns and space use in two species, Schoolmaster snapper (Lutjanus apodus) and Stoplight parrotfish (Sparisoma viride). We investigated the spatial overlap between the two species and compared intra-specific spatial overlap between day and night. Presence-absence models showed different diel presence and habitat use patterns between the two species. We constructed a spatial network of the movement patterns, which showed that for both species when fish were detected by the array of receivers most movements were made around the coral reef habitat while occasionally moving to silt habitats. Our results show that most individuals made predictable daily crepuscular migrations between different locations and habitat types, although individual behavioral changes were observed for some individuals across time. Our study also highlights the necessity to consider multiple species during MPA implementation and to take into account the specific biological and ecological traits of each species. The low number of fish detected within the receiver array, as well as the intraspecific variability observed in this study, highlight the need to compare results across species and individuals to be used for MPA management.
Resumo:
This study aimed to evaluate the population ecology of Hydrochoerus hydrochaeris (Linnaeus, 1766) in two urban areas in the north of Paraná, an open and other protected by assessing the effects of these two different types of environments on the structure and dynamics of the population and its implications for conservation of the species. The monitoring of the populations were performed monthly between June 2014 and March 2015 in Jaboti Lake Park (Apucarana / PR) and Conservation Unit Parque Arthur Thomas (Londrina / PR). To conduct the survey population data was used the methodology of total census (direct counting of individuals).They were evaluated ecological parameters of the populations of capybaras, such as ecological density, abundance, age distribution and birth rate, as well as performed the analysis of the landscape. It was applied to analysis of variance (ANOVA) to test the differences between the averages of the abundance of each age group per year of observation, as well as the differences between the average ecological density over the years of observation. The standard relationship between the use of classes and land use in the landscape and the ecological parameters of the capybara populations was evaluated by Principal Component Analysis (PCA). The trend of variation of average abundance over time to Thomas Arthur Park revealed abrupt decrease of the population in a short period of time (2014 16 ± 9, 14 ± 1 and 2015 7±1) as well as ecological density in 2015 (0.05 ind./ha). On the other hand, the Jaboti Lake Park, showed an increase in absolute abundance, with marked recovery of the population in the same period (2014 38±8,30 and 2015 45±1,73) and coming up with an ecological density in 2015 (2 ind ./ha). The birth rate found Lake Park Jaboti was superior to Arthur Thomas Park, which had a negative rate between 2012 and 2015. The use and land cover analysis showed significant differences from the point of view of the relative contribution of landscape elements in the spatial heterogeneity. Arthur Thomas Park shows areas of dense vegetation and urban areas relatively higher than those observed in Jaboti Lake Park that revealed relatively higher proportions of the areas of agriculture / field and exposed soil. Thus, the present study revealed that the local population structure is directly related to the spatial characteristics of both studied landscapes, as can be seen by the greater abundance and density seen in Jaboti Lake Park compared to Arthur Thomas Park in recent years of study.
Resumo:
Within land vertebrate species, snakes display extreme variations in their body plan, characterized by the absence of limbs and an elongated morphology. Such a particular interpretation of the basic vertebrate body architecture has often been associated with changes in the function or regulation of Hox genes. Here, we use an interspecies comparative approach to investigate different regulatory aspects at the snake HoxD locus. We report that, unlike in other vertebrates, snake mesoderm-specific enhancers are mostly located within the HoxD cluster itself rather than outside. In addition, despite both the absence of limbs and an altered Hoxd gene regulation in external genitalia, the limb-associated bimodal HoxD chromatin structure is maintained at the snake locus. Finally, we show that snake and mouse orthologous enhancer sequences can display distinct expression specificities. These results show that vertebrate morphological evolution likely involved extensive reorganisation at Hox loci, yet within a generally conserved regulatory framework.
Resumo:
Marine ecosystems are facing a diverse range of threats, including climate change, prompting international efforts to safeguard marine biodiversity through the use of spatial management measures. Marine Protected Areas (MPAs) have been implemented as a conservation tool throughout the world, but their usefulness and effectiveness is strongly related to climate change. However, few MPA programmes have directly considered climate change in the design, management or monitoring of an MPA network. Under international obligations, EU, UK and national targets, Scotland has developed an MPA network that aims to protect marine biodiversity and contribute to the vision of a clean, healthy and productive marine environment. This is the first study to critically analyse the Scottish MPA process and highlight areas which may be improved upon in further iterations of the network in the context of climate change. Initially, a critical review of the Scottish MPA process considered how ecological principles for MPA network design were incorporated into the process, how stakeholder perceptions were considered and crucially what consideration was given to the influence of climate change on the eventual effectiveness of the network. The results indicated that to make a meaningful contribution to marine biodiversity protection for Europe the Scottish MPA network should: i) fully adopt best practice ecological principles ii) ensure effective protection and iii) explicitly consider climate change in the management, monitoring and future iterations of the network. However, this review also highlighted the difficulties of incorporating considerations of climate change into an already complex process. A series of international case studies from British Columbia, Canada; central California, USA; the Great Barrier Reef, Australia and the Hauraki Gulf, New Zealand, were then conducted to investigate perceptions of how climate change has been considered in the design, implementation, management and monitoring of MPAs. The key lessons from this study included: i) strictly protected marine reserves are considered essential for climate change resilience and will be necessary as scientific reference sites to understand climate change effects ii) adaptive management of MPA networks is important but hard to implement iii) strictly protected reserves managed as ecosystems are the best option for an uncertain future. This work provides new insights into the policy and practical challenges MPA managers face under climate change scenarios. Based on the Scottish and international studies, the need to facilitate clear communication between academics, policy makers and stakeholders was recognised in order to progress MPA policy delivery and to ensure decisions were jointly formed and acceptable. A Delphi technique was used to develop a series of recommendations for considering climate change in Scotland’s MPA process. The Delphi participant panel was selected for their knowledge of the Scottish MPA process and included stakeholders, policy makers and academics with expertise in MPA research. The results from the first round of the Delphi technique suggested that differing views of success would likely influence opinions regarding required management of MPAs, and in turn, the data requirements to support management action decisions. The second round of the Delphi technique explored this further and indicated that there was a fundamental dichotomy in panellists’ views of a successful MPA network depending upon whether they believed the MPAs should be strictly protected or allow for sustainable use. A third, focus group round of the Delphi Technique developed a feature-based management scenario matrix to aid in deciding upon management actions in light of changes occurring in the MPA network. This thesis highlights that if the Scottish MPA network is to fulfil objectives of conservation and restoration, the implications of climate change for the design, management and monitoring of the network must be considered. In particular, there needs to be a greater focus on: i) incorporating ecological principles that directly address climate change ii) effective protection that builds resilience of the marine and linked social environment iii) developing a focused, strong and adaptable monitoring framework iv) ensuring mechanisms for adaptive management.
Resumo:
Urbanization is a global process contributing to the loss and fragmentation of natural habitats. Many studies have focused on the biological response of terrestrial taxa and habitats to urbanization. However, little is known regarding the consequences of urbanization on freshwater habitats, especially small lentic systems. In this study we examined aquatic macroinvertebrate diversity (family and species level) and variation in community composition between 240 urban and 784 non-urban ponds distributed across the UK. Contrary to predictions, urban ponds supported similar numbers of invertebrate species and families compared to non-urban ponds. Similar gamma diversity was found between the two groups at a family level, and while at a species level gamma diversity was higher in non-urban ponds, this difference was not statistically significant. The biological communities of urban ponds were markedly different to those of non-urban ponds and the variability in urban pond community composition was greater than that in non-urban ponds, contrary to previous work showing homogenisation of communities in urban areas. Positive spatial autocorrelation was recorded for urban and non-urban ponds at 0-50 km (distance between pond study sites) and negative spatial autocorrelation was observed at 100-150 km, and was stronger in urban ponds in both cases. Ponds do not follow the same ecological patterns as terrestrial and lotic habitats (reduced taxonomic richness) in urban environments; in contrast they support high taxonomic richness and contribute significantly to regional faunal diversity. Individual cities are complex structural mosaics which evolve over long periods of time and are managed in diverse ways, promoting the development of a wide-range of environmental conditions and habitat niches in urban ponds which can promote greater heterogeneity between pond communities at larger scales. Ponds provide an opportunity for managers and environmental regulators to conserve and enhance freshwater biodiversity in urbanized landscapes whilst also facilitating key ecosystem services including storm water storage and water treatment.
Resumo:
The effect of protected cropping on the performance of two strawberry cultivars ('Festival' and 'Rubygem') and two breeding lines (Breeding Lines 1 and 2) was studied in subtropical Queensland, Australia over two years. Production in this area is affected by rain, with direct damage to the fruit and the development of fruit diseases before harvest. The main objective of the study was to determine whether plants grown under high plastic tunnels had less rain damage, less disease incidence, and higher yields than plants grown outdoors. Our studies show that marketable yields were up to 40% higher in the plants under the tunnels compared with yields of the plants outdoors. This was mainly because fruit from the plants grown under the tunnels had lower incidences of rain damage and/or grey mould. There were no consistent differences in the relative numbers of small and/or misshaped fruit in the two growing environments. This research highlights the potential of protected cropping for strawberry producers in subtropical areas that receive significant rainfall during the growing season.
Resumo:
Over time, humanity began to realize the negative impact that the modern world has caused to the environment. The Atlantic Forest is one of the richest biomes in biodiversity, covering more than 60% of all species on the planet. This biome covered about 15% of the Brazilian territory, leaving currently only 7% of its fully fragmented forest remnants. This was the biome that suffered most from modernization and strong anthropogenic pressures in Brazil. For the account of environmental degradation, in the second half of the nineteenth century there was a shift in thinking, giving greater emphasis on conservation of some natural landscapes, with the intention of removing the man still preserved nature. Based on American models of conservation there were created the Nature Conservation Units. This study aimed to analyze the environmental quality of the State Park Vitório Piassa, a Conservation Unit located in the city of Pato Branco - PR. The environmental quality was measured by use of bio-indicators and some environmental pressures that the Park has suffered over the years also were identified. Beetles of the familiy Scarabaeinae (Coleoptera: Scarabaeidae) were used as the bioindicators. To compare the most conserved areas and the most degraded areas of the Park, three specific sites were defined within the Atlantic Forest fragment, these insects were captured with pitfall traps and identified as to their species and genera. There were two collections in February and March 2015, which resulted in 945 individuals in 22 species and nine different genus. Then the population of beetles in each area were classified based on ecological measures such as species richness, abundance of individuals of each species through diversity index (Shannon and Simpson) to identify the differences between the sampled groups and equitability (Pielou) to measure the distribution of the total abundance of the species in each area. To meet the objective of identifying the environmental pressures that occur in PEVP, evidence were collected through photographs, watching the field, aerial images and conversations with the resident population in the park. Similarly, if made relevant to build on the project running by the municipality for the construction of infrastructure for public viewing. These data served as subsidies to confront the current situation of the park and the current Brazilian legislation for UC's of full protection, highlighting the existing socio-environmental conflicts in the park, involving political issues and the proximity of the Conservation Unit with the urban area of the city.