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1.
Environ Monit Assess ; 193(10): 624, 2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34477980

RESUMEN

Monitoring and Assessment (M&A) of environmental resources aims to support the formulation of policies and follow up on outcomes of their implementation. In this study, the state of M&A is explored for Ethiopia with a focus on forests and water resources. The study is intended to serve as recommendations for future M&A applications in Ethiopia, as well as fulfillment of SDGs and other national and international commitments. Expert meetings, key informant interviews, and selected document analysis served as sources of information. The findings were summarized using qualitative grading and institutional mapping. Basic results of the study are that monitoring data on climate and streamflow are standardized in forms that can be communicated to policymakers. Scantier and less standardized are environmental data on soils, sediment transport, forests, biodiversity, and air quality. Water quality, soil moisture, groundwater level, forest biomass, and soil carbon are rarely monitored and can only be found in reports or studies for the fulfillment of academic degree requirements. Resources like nutrient fluxes have rarely been documented, not at all in some cases. There is considerable scope for tapping both technological advances and experiences of citizen science and local participation in environmental governance to rapidly expand and improve monitoring from local to regional and national scales. The study showed that there is a need for establishing a coordinated national system for monitoring and assessing the status of the environment, including the use of natural resources. Communicating such data to the scientific and wider public will support evidence-based planning and policy-making towards national development.


Asunto(s)
Conservación de los Recursos Naturales , Agua , Monitoreo del Ambiente , Política Ambiental , Etiopía , Bosques
2.
J Environ Manage ; 300: 113748, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34543962

RESUMEN

Land-use/cover change is the major cause of terrestrial ecosystem degradation. However, its impacts will be exacerbated due to climate change and population growth, driving agricultural expansion because of higher demand of food and lower agricultural yields in some tropical areas. International strategies aimed to mitigate impacts of climate change and land use-cover change are challenging in developing regions. This study aims to evaluate alternatives to minimize the impacts of these threats under socioeconomic trajectories, in one of the biologically richest regions in Guatemala and Mexico. This study is located at the Usumacinta watershed, a transboundary region that shares a common history, with similar biophysical properties and economic constraints which have led to large land use/cover changes. To understand the impacts on deforestation and carbon emissions of different land-management practices, we developed three scenarios (1): business as usual (BAU), (2) a reducing emissions scenario aimed to reduce deforestation and degradation (REDD+), and (3) zero-deforestation from 2030 onwards based on the international commitments. Our results suggest that by 2050, natural land cover might reduce 22.3 and 12.2% of its extent under the BAU and REDD + scenarios, respectively in comparison with 2012. However, the zero-deforestation scenario shows that by 2050, it would be possible to avoid losing 22.4% of the forested watershed (1.7 million ha) and recover 5.9% (0.4 million hectares) of it. In terms of carbon sequestration, REDD + projects can reduce the carbon losses in natural vegetation, but a zero-deforestation policy can double the carbon sequestration produced by REDD + projects only. This study shows that to reduce the pressures on ecosystems, particularly in regions highly marginalized with significant migration, it is necessary to implement transboundary land-management policies that also integrate poverty alleviation strategies.


Asunto(s)
Cambio Climático , Ecosistema , Agricultura , Conservación de los Recursos Naturales , Bosques
3.
J Insect Sci ; 21(5)2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34553221

RESUMEN

Hollows of veteran trees (i.e., rot holes) provide habitat for many rare and threatened saproxylic invertebrates. Rot holes are highly heterogeneous, particularly in terms of substrate and microclimate conditions. There is, however, a dearth of information regarding the differences in biological communities inhabiting rot holes with different environmental conditions. Invertebrates were sampled from European beech (Fagus sylvatica) rot holes in Windsor, Savernake, and Epping Forests (United Kingdom). For each rot hole, physical and environmental conditions were measured, including tree diameter, rot hole dimensions, rot hole height, substrate density, water content, and water potential. These parameters were used to assess the influence of environmental conditions and habitat characteristics on invertebrate communities. Rot hole invertebrate communities were extremely diverse, containing both woodland generalist and saproxylic specialist taxa. Large variation in community structure was observed between rot holes and across woodlands; all sites supported threatened and endangered taxa. Environmental conditions in rot holes were highly variable within and between woodland sites, and communities were predominantly structured by these environmental conditions. In particular, turnover between invertebrate communities was linked to high ß-diversity. The linked heterogeneity of environmental conditions and invertebrate communities in rot holes suggests that management of deadwood habitats in woodlands should strive to generate environmental heterogeneity to promote invertebrate diversity. Additional research is required to define how management and conservation activities can further promote enhanced biodiversity across rot holes.


Asunto(s)
Biodiversidad , Bosques , Invertebrados , Animales , Biota , Conservación de los Recursos Naturales , Ecosistema , Fagus , Árboles
4.
J Environ Manage ; 299: 113655, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34488109

RESUMEN

Ecological environmental assessment is an indispensable part of the eco-environment protection system. As researchers have increasingly focused on ecological environment protection, the ecological environment evaluation system has been gradually improved. The enhancement of the ecological environment evaluation system provides more scientific and effective data support for ecological environment monitoring and governance. This article examines the Wuhan Urban Development Zone as an example, selects Landsat 8 (Operational Land Imager/Thermal Infrared Sensor (OLI/TIRS)) images of the study area from 2013 to 2019 at two-year intervals, and applies a new type of ecological environment evaluation index named the remote sensing ecological index with local adaptability (RSEILA) to assess the eco-environment. The RSEILA represents an improvement of the remote sensing ecological index (RSEI) proposed in 2013. The RSEILA enhancement is mainly reflected in the correlation and spatial distribution characteristics between geographical elements. The results reveal that 1) the overall urban ecological environment in the Wuhan Urban Development Zone demonstrates a downward trend from 2013 to 2019, and the rate of decline during the period varies. 2) RSEILA decline is mainly found in the far suburbs, and ecological environment degradation mainly occurs due to the change in land-use type caused by the suburbanization process of urban expansion. 3) Because of the implementation of urban greening projects, the phenomenon of ecological environment optimization (green recovery) is observed in the central urban area of Wuhan. 4) Land use exhibits a notable correlation with the ecological environment, and different land-use types exhibit distinct degrees of ecological environment deterioration. The order of deterioration is: bare soil/sand > building > cropland > forests.


Asunto(s)
Monitoreo del Ambiente , Tecnología de Sensores Remotos , China , Ciudades , Conservación de los Recursos Naturales , Ecosistema , Bosques
5.
J Environ Manage ; 299: 113606, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34523540

RESUMEN

Forest certification has emerged as a voluntary, market-driven tool for sustainable forest management (SFM). Its legitimacy depends on its ability to achieve its objectives and to retain the support of stakeholders such as NGOs and the companies that adopt it. This study presents a novel approach for assessing the contributions of forest certification to biodiversity conservation, based on Forest Stewardship Council (FSC) certification in four northern European countries (Finland, Sweden, Estonia, Latvia). In each case, national FSC certification requirements related to specific biodiversity targets were compared with requirements in national legislation. Nearly 80% of the assessed certification requirements were more prescriptive than the national legislation. One-third of these requirements (3-8 per country) were assessed to have a positive contribution to biodiversity conservation, whereas four requirements (up to 2 per country) were assessed to have a low positive contribution. FSC requirements to protect Woodland Key Habitats were identified as having a positive contribution in all four countries, whereas requirements regarding live tree retention in harvests and preserving dead wood had a positive contribution in three countries each. Despite often prescribing similar measures, the other requirements with positive contributions varied between countries depending on the national legislative baseline. The remaining requirements could not be assessed through expert evaluation, indicating the need for additional empirical research to evaluate how the normative requirements translate to impacts in the field, and how the national context may affect their implementation. The approach is globally applicable, repeatable, and provides a basis for designing systematic empirical assessments of the certification impact.


Asunto(s)
Conservación de los Recursos Naturales , Agricultura Forestal , Biodiversidad , Certificación , Bosques
6.
Environ Monit Assess ; 193(9): 547, 2021 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-34341861

RESUMEN

Assessing carbon storage and sequestration is key for defining effective conservation actions to mitigate climate change. Forest species changes have direct impacts on carbon stocks and may lead to undesirable climate trade-offs. In this paper, we measure aboveground biomass (AGB) and the impact of forest changes on climate regulation through three land policy scenarios by 2030 in continental Portugal. We found that a High intervention scenario, supported by an important increase in "Other coniferous trees" class, will provide 29.5% more of carbon sequestration, whereas a Low intervention scenario, in which there is a moderate increase in all forest classes, will result in an increase of 5.7%. A business as usual (BAU) scenario, supported by an increase in eucalyptus forests and a decrease in autochthonous species, will decrease carbon sequestration (-2.7%), particularly Lisboa, Algarve and North regions. Economic valuation shows that the High intervention scenario will generate the highest economic outcome for climate regulation by 2030. This study provides a spatial-based methodology for monitoring carbon sequestration and new insights about the impact of policies for Green House Gas (GHG) mitigation, supporting the 2030 Sustainable Development Goals achievement.


Asunto(s)
Secuestro de Carbono , Monitoreo del Ambiente , Biomasa , Carbono/análisis , Cambio Climático , Conservación de los Recursos Naturales , Bosques , Portugal , Árboles
7.
Biol Lett ; 17(8): 20210069, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34376076

RESUMEN

Anthropogenic environmental change can underpin major shifts in natural selective regimes, and can thus alter the evolutionary trajectories of wild populations. However, little is known about the evolutionary impacts of deforestation-one of the most pervasive human-driven changes to terrestrial ecosystems globally. Absence of forest cover (i.e. exposure) has been suggested to play a role in selecting for insect flightlessness in montane ecosystems. Here, we capitalize on human-driven variation in alpine treeline elevation in New Zealand to test whether anthropogenic deforestation has caused shifts in the distributions of flight-capable and flightless phenotypes in a wing-polymorphic lineage of stoneflies from the Zelandoperla fenestrata species complex. Transect sampling revealed sharp transitions from flight-capable to flightless populations with increasing elevation. However, these phenotypic transitions were consistently delineated by the elevation of local treelines, rather than by absolute elevation, providing a novel example of human-driven evolution in response to recent deforestation. The inferred rapid shifts to flightlessness in newly deforested regions have implications for the evolution and conservation of invertebrate biodiversity.


Asunto(s)
Ecosistema , Insectos , Animales , Biodiversidad , Conservación de los Recursos Naturales , Bosques , Humanos , Alas de Animales
8.
Artículo en Inglés | MEDLINE | ID: mdl-34444133

RESUMEN

Researchers and managers of natural resource conservation have increasingly emphasized the importance of maintaining a connected network of important ecological patches to mitigate landscape fragmentation, reduce the decline of biodiversity, and sustain ecological services. This research aimed to guide landscape management and decision-making by developing an evaluation framework to construct ecological security patterns. Taking the Jianghan Plain as the study area, we identified key ecological sources by overlaying the spatial patterns of ecological quality (biodiversity, carbon storage, and water yield) and ecological sensitivity (habitat sensitivity, soil erosion sensitivity, and water sensitivity) using the Integrated Valuation of Environmental Services and Tradeoffs (InVEST) model and the Chinese Soil Loss Equation Function. Ecological corridors were obtained by the least-cost path analysis method and circuit theory. A total of 48 ecological sources (3812.95 km2), primarily consisting of water area, forestland, and cropland, were identified. Ninety-one ecological corridors were derived, with a total length of 2036.28 km. Forty barriers and 40 pinch points with the highest improvement coefficient scores or priority scores were selected. There were 11 priority corridors with very high levels of connectivity improvement potential and conservation priority, occupying 16.15% of the total length of corridors. The overall potential for ecological connectivity is high on the Jianghan Plain. Our framework offers a valuable reference for constructing ecological security patterns and identifying sites for ecological restoration at the regional scale.


Asunto(s)
Conservación de los Recursos Naturales , Ecología , China , Ecosistema , Bosques
9.
Environ Monit Assess ; 193(9): 563, 2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34379209

RESUMEN

Restoring degraded forest is essential if we are to reduce human pressure on natural ecosystems and their biodiversity. Forests were nationalized in 1957 in Nepal and as a consequence, forest cover declined from 45% in 1964 to just 29% in 1994. However, as its response, sectoral plans and policies, particularly introduction of community-based forest management programs since the 1980s and conservation activities resulted in large scale forest cover restoration. Here, we examined the forest cover change in the Gandaki River Basin (GRB), the catchment with the largest altitudinal variation (ranging from ± 93 to 8167 m) and environmental and ecological significance. To see how forests have changed since then, we analyzed snapshots of spatiotemporal, ecological and physiographic changes in forest cover, and forest type at decadal intervals from 1996 to 2016 using Landsat 5 and 8 satellite images. We observed an overall gain in forest cover of 207 km2, from 7571 km2 (34.4% of the total area) in 1996 to 7778 km2 (35.3%) in 2016. Of the 21 forest cover types identified, the greatest forest coverage during 2016 was of Schima-Castanopsis forest (25.9%) and hill sal forests (16.4%). In terms of physiographic zones, land below 500 m (Tarai) where most people live, witnessed gradual declines in forest cover, in contrast to large increases in forests above 500 m. Historical examination of forest cover at ecological and physiographic scales helps to identify the elevation-wise distribution of forest resources, vegetation composition, ecosystem characteristics, anthropogenic pressure upon vegetation, and hence the overall influence of LULC upon the environment. These outputs will assist planners, policy makers, and researchers in their formulation of effective basin wide plans and policies to ensure the protection of basin level biodiversity and ecosystem function.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Monitoreo del Ambiente , Bosques , Humanos , Nepal
10.
Braz J Biol ; 83: e246002, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34378665

RESUMEN

Economic valuation of ecosystem services is a new concept in forest management. Economic valuation provides basis for payment for ecosystem services (PES). Therefore, objective of this study was to evaluate eco-tourism and carbon stock services of the Maindam valley, District Swat, Pakistan. For the carbon stock calculation, a sample size of 155 plots of 0.1 hectare (Ha) was taken using preliminary survey at 95% confidence interval and 10% allowable error. The data for tourism services was collected from owners of all the hotels, 100 tourists and key informants of the area at 10% sampling intensity on pretested questionnaire for twenty years period (1997-2017). Results showed that Miandam valley has carbon stock worth US$ 16,306,000 while the value of eco-tourism was US$ 1,578,458 on annual basis. The results also showed that trend of tourism has drastically declined after the 9/11 incident for foreigners and locals and the situation was further deteriorated during the era of Talibanization or militancy from 2008-2011. This study recommends implementation of PES strategy at the rate of 5%, thus a total of US$ 78,922 can be earned from eco-tourism and carbon crediting in the study area annually, which could play important role in sustainable forest management.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Carbono/análisis , Bosques , Pakistán
12.
Sci Total Environ ; 797: 149183, 2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34346354

RESUMEN

Holistic planning and management of landscape is a prominent challenge. This paper provides a methodological framework for the assessment of an integrated land management plan with its action plans. Based on the scientific understanding, contemporary literature and the legal documents, a set of planning principles was developed and the strengths and weaknesses of the plan highlighted. Besides some shortcomings, the assessment indicated that the plan is a good initiative for a Sustainable Land Management (SLM) paradigm. The plan was based on a forest management plan from which the other action plans such as apiculture plan, grazing plan, biodiversity plan, non-wood products (NWFP) plan and income generating plan orbit around. A new inventory procedure was developed to determine growing stock in degraded forests. The climate change effects on four land use categories were projected with a limited set of measurements. Carbon storage was calculated for all land uses by considering various carbon pools. A typical governance option was proposed where each state organization prepare and implement their own activities according to the rights and responsibilities defined in the legal documents. While spatial database with thematic maps and attributes was built with GIS and remote sensing, the essential thematic maps such as land capability classes, non-systematic and traditional knowledge were absent. The lack of holistic planning vision, scenario analysis with sound decision making tools and methods, and insufficient participation, implementation and monitoring process were identified as major drawbacks. These shortcomings have created a significant design and governance concern and jeopardized by far the sustainable implementation of SLM activities. Consequently, a sound planning framework with its necessary components was developed as a basis for a comprehensive SLM and the appropriate revisions were proposed to improve each component of the plan.


Asunto(s)
Biodiversidad , Bosques , Cambio Climático , Conservación de los Recursos Naturales , Turquia
13.
J Environ Manage ; 298: 113470, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34365182

RESUMEN

Indigenous agroforestry systems are important reservoirs of biodiversity, and ecosystem services with a potential contribution for conservation of biodiversity while sustaining the livelihood of the rural populace. Pineapple (Ananas comosus) agroforestry systems (PAFS) form an essential constituent of the rural landscape in the Indian Eastern Himalayas and other parts of Asia. The traditional PAFS management in southern Assam is unique in that it involves shifting cultivation transitioning from native forests to a PAFS. Scarcity of information on the functioning and services in terms of species diversity and carbon storage potential in the traditional PAFS has restricted the opportunities for consideration under the nature-based solutions of climate action including REDD+. Therefore, the present study assessed the tree diversity and ecosystem carbon storage in a chronosequence from swidden agriculture through different phases of PAFS establishment. The result demonstrated that basal area in the PAFS increased with age. The most dominant species in the native forests was Palaquium polyanthum, while agricultural land use and PAFS aged <5, 11-15 and > 15 years old were dominated by Gmelina arborea, Albizia procera, Areca catechu and Hevea brasiliensis, respectively. The highest value of Shannon-Wiener diversity index (H) was recorded in native forests (2.71), and lowest in 5-10 years old PAFS. The ecosystem carbon storage declined from 261.43 Mg ha-1 in native forests to 181.07 Mg ha-1 in <5-years old PAFS. In <5 years old PAFS, the ecosystem carbon storage was 30 % lower than the native forest; while at >15 years it was merely 5 % less than the native forests. The traditional PAFS maintains a steady ecosystem carbon stock while reducing land use related carbon emission and providing additional co-benefits to the communities. Therefore, the traditional PAFS constitute a good opportunity for REDD+.


Asunto(s)
Carbono , Árboles , Biodiversidad , Conservación de los Recursos Naturales , Ecosistema , Bosques
14.
J Environ Manage ; 298: 113533, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34411797

RESUMEN

Among the many causes of habitat loss, urbanization coupled with climate change has produced some of the greatest local extinction rates and has led to the loss of many native species. Managing native vegetation in a rapidly expanding urban setting requires land management strategies that are cognizant of these impacts and how species and communities may adapt to a future climate. Here, we demonstrate how identifying climate refugia for threatened vegetation communities in an urban matrix can be used to support management decisions by local government authorities under the dual pressures of urban expansion and climate change. This research was focused on a local government area in New South Wales, Australia, that is undergoing significant residential, commercial and agricultural expansion resulting in the transition of native forest to other more intensive land-uses. Our results indicate that the key drivers of change from native vegetation to urban and agriculture classes were population density and the proximity to urban areas. We found two of the most cleared vegetation community types are physically restricted to land owned or managed by council, suggesting their long-term ecological viability is uncertain under a warming climate. We propose that land use planning decisions must recognize the compounding spatial and temporal pressures of urban development, land clearing and climate change, and how current policy responses, such as biodiversity offsetting, can respond positively to habitat shifts in order to secure the longevity of important ecological communities.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Biodiversidad , Ecosistema , Bosques
15.
J Environ Manage ; 298: 113504, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34426227

RESUMEN

Understanding local stakeholders' perceptions of co-management institutional activities serves a significant role in the proper functioning of the co-management institutions for the Sundarban mangrove forest conservation effort, but this currently remains unexplored. This study aimed to identify the current co-management institutions, co-management activities, and local people's understanding of these activities in the implementation of the co-management approach. The study was conducted in four villages in the Chandpai range of the Sundarban mangrove forest. Thematic content analysis was conducted on the qualitative data, which had been collected through key informant interviews at the local, regional and national levels, followed by focus group discussions in the study villages. The key forest co-management activities and practices identified were: forest protection and monitoring; meetings; local livelihood initiatives; and organisational supports. These co-management activities were implemented through institutions largely situated at the local level, through Village Conservation Forum, People's Forum and Community Patrol Group; higher-level institutions included the Co-management Committee, where local, district and national stakeholders were represented. Local people with forest dependency were participating in forest co-management activities and their awareness of forest conservation and social network had increased. In addition, people who had received training from government and non-government organisations reported benefits such as improved resource harvesting techniques, organisational skills and practical knowledge, which would be useful in times of natural disasters. However, local people also reported a range of issues affecting their full participation, which included top down decision-making, insignificant financial support, absence of alternate income sources, lack of meeting places for VCF members, gender inequality in participation, corruption and lack of skill-based training. A key governance issue for the local-level forest co-management institutions was limited access to the government organisations who oversaw policy and institutional control. In contrast, non-government organisations provided important institutional capacity-building support to local communities, and acted as a conduit to higher level committees. Broader impact could be achieved by fostering local participation, especially that of women, through genuine collaboration with other stakeholders, and extending the lessons learned from the study villages through exchange visits and sharing of ideas with other VCF villages in the area.


Asunto(s)
Bosques , Humedales , Bangladesh , Conservación de los Recursos Naturales , Femenino , Instituciones de Salud , Humanos , Renta
16.
Sci Data ; 8(1): 220, 2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34404811

RESUMEN

Primary forests, defined here as forests where the signs of human impacts, if any, are strongly blurred due to decades without forest management, are scarce in Europe and continue to disappear. Despite these losses, we know little about where these forests occur. Here, we present a comprehensive geodatabase and map of Europe's known primary forests. Our geodatabase harmonizes 48 different, mostly field-based datasets of primary forests, and contains 18,411 individual patches (41.1 Mha) spread across 33 countries. When available, we provide information on each patch (name, location, naturalness, extent and dominant tree species) and the surrounding landscape (biogeographical regions, protection status, potential natural vegetation, current forest extent). Using Landsat satellite-image time series (1985-2018) we checked each patch for possible disturbance events since primary forests were identified, resulting in 94% of patches free of significant disturbances in the last 30 years. Although knowledge gaps remain, ours is the most comprehensive dataset on primary forests in Europe, and will be useful for ecological studies, and conservation planning to safeguard these unique forests.


Asunto(s)
Conservación de los Recursos Naturales , Bosques , Bases de Datos Factuales , Europa (Continente)
17.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2545-2554, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34313073

RESUMEN

The middle and upper reaches of Ganjiang River is an important functional area for soil and water conservation in the southeastern hills of China. It is important to analyze the land use change and their driving forces at different spatial and temporal scales to maintain and optimize the local ecological functions. We analyzed the land use structure and land use dynamics in the middle and upper reaches of Ganjiang River from 1980-2018 based on 1 km spatial resolution land use data, and analyzed the spatial heterogeneity and driving factors of land use change using principal component analysis (PCA), ordinary least squares (OLS) and geographically weighted regression (GWR). From 1980-2018, the main land use types in the study area were forests (proportion 69.4%-71%) and cultivated land (proportion 20.8%-20.9%). Land use dynamic degree of build-up land and unused land were larger, and the comprehensive land use dynamic degree gradually increased, especially in 2010-2018. The GWR model had a better fitting effect on the analysis of land use change drivers, which was better in 98.6% of the area. Among the influencing factors of the spatial heterogeneity of land use change in the study area, the natural environment factors were the most obvious, with a restrictive role. The socio-economic factors were the secondary in importance, with a promoting role. The comprehensive influence of natural and social factors were weak and complex.


Asunto(s)
Bosques , Ríos , China , Conservación de los Recursos Naturales , Suelo , Regresión Espacial
18.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2555-2564, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34313074

RESUMEN

The identification of ecological sources and corridors plays an important role in the construction of ecological security pattern. However, previous studies mainly concentrated on the optimal path selection of species migration and diffusion rather than the random path selection of the species, which makes most conclusions fail to objectively reveal the process of species migration and diffusion. Taking the downtown area of Hengyang City as an example, we selected the ecological sources and ecological corridors with the habitat quality analysis module of InVEST and Circuitscape 4.0 and evaluated the importance and connectivity of relevant ecological elements with the Linkage Mapper, with the aim to construct the ecological security pattern and delimitate the regions prior to ecological restoration. The results showed that there were 85 ecological sources dominated by woodland and grassland, together with a small number of ponds and beaches, which mainly distributed in the southwest of Zhengxiang District, the west of Yanfeng District, the northeast and south central of Zhuhui District, with a total area of 11.8 km2. There were 60 ecological sources with centrality greater than 100, accounting for 70.6% of the total. There were 217 ecological corridors and five potential ecological corridors mainly composed of forest land, among which the proportion of shrubbery and sparse forest land was higher. The corridors with higher importance were mainly distributed in the west of the studied area. After removing the barriers, the regional connectivity had been significantly improved, with the highest extent of 54.9%. The priority areas of ecological restoration were classified into three levels according to the value of cumulative current, namely, the high-grade area, the middle-grade area and the low-grade area. The high-grade area covered 4.3 km2 of barriers, mainly distributed in the southwest of Zhengxiang District, northeast and south central of Zhuhui District. The middle-grade area was dominated by pinch area and ecological source area with centrality less than 100, covering an area of about 12.9 km2, mainly distributed in the central part of Zhengxiang District, northeast and south central of Zhuhui District. The low-level area was mainly distributed in south central of Zhuhui District, with 51.8 km2 of residual ecological sources. By coupling InVEST habitat quality analysis module and circuit theory, the ecological security pattern for biological protection was constructed, which provides scientific reference for biological protection.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , China , Ciudades , Ecología , Bosques
19.
Environ Monit Assess ; 193(8): 502, 2021 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-34292412

RESUMEN

Political instability and economic crises may trigger informal, unsustainable and often illegal land use, leading to land degradation. One of the most recent and striking examples of such a phenomenon within Europe is demonstrated by the Polissia region in Northern Ukraine, famous for its amber deposits. Amid severe political disturbances and subsequent economic recession in Ukraine in 2014 and 2015, amber mining flourished in the region. However, the extent and spatial pattern of degraded land caused by amber mining over the entire region has remained unknown. To fill this gap and track land surface changes, we used multi-source satellite imagery. We found a gradual decrease of the area without vegetation cover, as a proxy for degraded land, from the late Soviet period until 2014 in most of the analysed administrative districts of Polissia. In contrast to this, we identified substantial conversion of forest and agricultural land to bare soil that occurred between 2014 and 2016, which can be attributed to the rush of illegal amber mining in the region. The estimated total area of affected land on the produced Landsat-based map for 2016 was 1066 ha, 60% of which occurred in 2014-2016. Land cover classification within a key study area suggests that utilization of very high-resolution images from the WorldView-2 satellite enables more accurate mapping of land degradation and identification of small mining sites. Further monitoring of land-use change caused by amber mining is essential to improving understanding of long-lasting environmental impacts on regional ecosystems and biodiversity.


Asunto(s)
Ámbar , Ecosistema , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Europa (Continente) , Bosques , Ucrania
20.
J Environ Manage ; 296: 113188, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34225045

RESUMEN

Ecosystem service (ES) mapping has been developed with the aim of supporting ecosystem management, but ES maps often lack information about uncertainty and risk, which is essential for decision-making. In this paper, we use a risk-based approach to map ES in mountain forests, which are experiencing an increasing rate of natural disturbances, such as windthrow, bark beetle outbreaks, and forest fires. These disturbances affect the capacity of forests to provide essential ecosystem services, such as protection from natural hazards, wood production, and carbon sequestration, thus posing a challenge for forest management. At the same time, disturbances may also have a positive effect on certain services, e.g. by improving habitats for species that rely on dead wood. We integrate forests' susceptibility to natural disturbances into probabilistic Bayesian Network models of a set of ES (avalanche protection, carbon sequestration, recreation, habitats, and wood production), which combine information from remote sensing, social media and in-situ data, existing process-based models, and local expert knowledge. We use these models to map the level of the services and the associated uncertainties under scenarios with and without natural disturbances in two case study areas in the Swiss Alps. We use clustering to identify bundles of risk to ES, and compare the patterns of risk between the non-protected area of Davos and the strictly protected area of the Swiss National park with its surroundings. The spatially heterogeneous pattern of risk to ES reflects topographic variability and the forest characteristics that drive disturbance susceptibility, but also the demand for ecosystem services. In the landscape of Davos, the most relevant risks to ES are related to decreases in the protection against avalanches and carbon sequestration, as well as some risk to wood production and recreation. In the strictly protected Swiss National Park, the overall level of ES risk is lower, with an increase in habitat quality under the disturbance scenario. This risk-based approach can help identify stands with high levels of ES that are particularly susceptible to disturbances, as well as forests with a more stable ES provision, which can help define priorities in forest management planning.


Asunto(s)
Ecosistema , Incendios Forestales , Teorema de Bayes , Secuestro de Carbono , Conservación de los Recursos Naturales , Bosques , Humanos
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