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The process of habitat fragmentation has three components: (a) an overall loss of habitat; (b) a reduction in the size of remaining habitats; and (c) an increased isolation of habitats.

The process of habitat fragmentation has three components: (a) an overall loss of habitat; (b) a reduction in the size of remaining habitats; and (c) an increased isolation of habitats.

Citations

... Limiting the degradation of the eco-environment and keeping urban sustainable development is one of the most pressing issues Fang et al. 2021). Ecological networks (ENs) map the most valuable areas that provide multiple ecological goods and services for human demands and have long been adopted worldwide for improving eco-environment under the scenarios of rapid urbanization (Behnaz and Mahdi 2010), such as natural protection strategies, climate change, and wildlife protection (Bennett 2003;Blasi et al. 2008;Behnaz and Mahdi 2010;Bennett 1999;Jongman 2002;Vuilleumier and Prelaz-Droux 2002;Jongman et al. Opdam et al. 2006;Huber et al. 2007;Gurrutxaga et al. 2010). ...
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Exploring the changes in ecological networks (ENs), its eco-environment effects and the differences in urban agglomerations in various urbanization stages are important for achieving sustainable ecosystem management and a better layout of ecological network. In this study, China’s three typical urbanization agglomerations, Beijing-Tianjin-Hebei urban agglomeration (BTH), Yangtze River Delta urban agglomeration (YRD), and Pearl River Delta urban agglomeration (PRD), were selected as the study area. Spatiotemporal changes in ENs, the changing patterns, its eco-environment effects, and impacts of rapid urbanization were analyzed by environment indices, buffer analysis, and correlation analysis. The results showed a great lost in ENs from 2000 to 2015. Four patterns were seen in changing ENs: decomposition process (DP), internal change process (ICP), polycondensation process (PP), and external change process (ECP). ICP was dominated in YRD and PRD. ECP was the main pattern in core areas of BTH. The correlation analysis with YRD as the example showed that the changes in ENs had a certain impact on the eco-environment, especially in the 10-km buffer zone. The decrease of ENs was related to the increase of developed land, and the closer to the core area, the higher the correlation coefficient was. Reduction of ENs would slow down to a certain extent, when the agglomeration is in a higher urbanization stage. Different directions of restoration and optimization of ENs were proposed for the three urban agglomerations. The study will provide support for sustainable management and restoration and optimization of ENs for China’s agglomerations.
... In addition, forested riparian zones close to rivers have been shown to be important for aquatic habitats and biota (Richardson & Béraud, 2014;Tolkkinen et al., 2020) and are often the least protected in areas used for intensive forestry (Kuglerová et al., 2020). However, headwater areas are impor-tant because, in addition to acting as dispersal corridors for aquatic, semi-aquatic and terrestrial organisms (Bennett et al., 1999;Tonkin et al., 2018), they are also important for the structure and dynamics of downstream reaches (Vannote et al., 1980). Therefore, joint conservation and restoration should aim to guarantee linkages between different river reaches to allow unprevented movements of organisms between sites, facilitate movements of organic matter within the river ecosystem and maintain connections between the river and its riparian zone (Tolkkinen et al., 2020;Turunen et al., 2021). ...
... While this is typically considered from the perspective of augmenting migratory salmon and trout populations, other organisms, such as aquatic insects and mussels relying on host fish for dispersal, might benefit from connectivity restoration which may require consideration of factors other than dam removal only. For example, this would entail protecting riparian forests that many terrestrial vertebrates and aquatic insects use for moving between locations (Bennett, 1999;Tonkin et al., 2018). In addition, restoring the lost connections between the river and its floodplain would be important because it would allow some species to use floodplains for spawning and create habitats for species dependent on off-mainstem river habitats. ...
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1. Freshwater ecosystems and their biota are more seriously threatened than their marine and terrestrial counterparts. A solution to halt increasing negative impacts of anthropogenic development would be to reconsider the basics of nature conservation (i.e. protection of pristine and near-pristine areas) and restoration (i.e. returning an impacted site to as natural condition as possible) through inclusion of the knowledge on abiotic and biotic dynamics of rivers draining pristine catchments. In boreal and Arctic regions, such comparisons are still possible because in addition to harbouring strongly modified drainage basins, some of the most natural drainage basins are also situated in these high-latitude areas. 2. A suitable approach for simultaneous planning of joint river conservation and restoration would be to (i) examine how well different kinds of rivers are covered by existing protected area networks and (ii) to restore parts of degraded rivers to facilitate colonization by aquatic and riparian organisms that have found havens in existing protected areas. This joint approach is a two-way road, as conservation and restoration benefit from each other by allowing river networks to facilitate movements of organisms and matter, thereby mimicking natural riverine meta-systems in anthropogeni-cally modified drainage basins, with restored sites acting as stepping-stones between protected areas. 3. We argue that existing policy instruments should consider the fact that river ecosystems are spatially and temporally dynamic meta-systems. These characteristics should be given due attention in conservation and restoration rather than relying on a static approach where a snapshot classification of river reaches is thought to be enough without considering underlying ecological dynamics. Taking ecological dynamics into account would contribute to sustainable management and maintenance of biodiversity and ecosystem services.
... With the daily increase in human activities, the process of habitat loss and fragmentation is inevitable, necessitating the conservation of the remaining fragmented core habitats for mammals, particularly carnivores (Bennett, 2003;Berger et al., 2008;Murphy et al., 2017). However, the available conservation areas (CAs, legally protected for biodiversity conservation in different categories of protection (Lausche and Burhenne-Guilmin, 2011)) are small or are not potentially appropriate for the conservation of carnivores (Cushman et al., 2013;Mohammadi et al., 2018). ...
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The process of habitat loss and fragmentation is inevitable with increasing human activities, necessitating conservation for the areas with the highest priorities (i.e., biodiversity hotspots). This study aimed to predict the core habitats of the eight mustelid species (family: Mustelidae) in Iran and detect mustelid diversity hotspots based on the highest species richness of these species to compare them with available conservation areas (CAs). Accordingly, habitat suitability modeling was carried out for each mustelid species through an ensemble approach, and species richness and mustelid diversity hotspots were determined by overlaying the predicted core habitats. The results revealed that the highest richness of the mustelid species was six species for the overlaid map of the modeled core habitats. The main mustelid diversity hotspots were along the Alborz Mountains and the Hyrcanian forest of northern Iran. There were some other hotspots along the Zagros Mountains in western Iran. CAs protected less than half of mustelid diversity hotspots, which means that wildlife managers should take into consideration the conservation action plan for the mustelid species in Iran. Besides, it is necessary to expand available CAs or establish new-targeted CAs according to mustelid diversity hotspots.
... Roads have been also shown to decrease edge permeability for some small mammal species such as the montane akodont Akodon montensis (Ascensão et al. 2017). Habitat fragmentation caused by road development might therefore result in high risk of extinction (Crooks et al. 2017), due to associated habitat loss and increased patch isolation (Bennett 2003), reducing the chances of local (re)colonization (McGregor et al. 2008). Besides, in addition to the reduction in animal populations, species movement behaviour may be impacted near roads (Coffin 2007). ...
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Roads are among the most widespread signs of man’s presence around the globe. From simple low traffic trails to wide and highly used highways, roads have a wide array of effects on wildlife. In the present study, we tested how habitat reduction by roads may affect the space use and movement patterns of the Cabrera vole ( Microtus cabrerae ), a near-threatened Iberian endemism, often living on road verges. A total of 16 voles were successfully radio-tracked in two habitat patches with different size and proximity to roads. Results showed that individuals from the smaller patch (Verge patch) had smaller and less complex home-ranges than those from the larger patch (Meadow patch). Movement patterns were significantly influenced by the day period but only in individuals from the Verge patch. There was evidence of a barrier effect in both habitat patches, being this effect much more noticeable in the verge population. Overall, this study shows that space use and movement patterns of Cabrera voles near roads may be affected by the degree of habitat reduction imposed by these infrastructures. This suggests that species space use and movement patterns at fine-scale should be accounted for in road planning, even for species that may benefit from road verge habitats as refuges.
... The system of agricultural and the cattle exploitation characteristic of the agrarian landscapes in this part of Central America demonstrate the intense interest in the normal practice of conserving patches of forest and other green areas within the lots, such as tree-fenced areas [60][61][62][63][64]. In the South Pacific region of Costa Rica, peasant and indigenous agricultural systems play an important ecological role thanks to the conservation of patches of woodland within the productive family lots, given that they act as a connective biological link between many fragments and counteract the isolating effect of intermediate agricultural terrains [65]. This practice also provides benefits regarding the protection of water resources, such as improving the flow and quality of the water [66,67], while riverbank vegetation helps regulate ecological processes in waterways and their associated habitats [68]. ...
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In Central America, Family Farming (FF) is characterized by the fostering of endogenous development, self-sustaining economies, food safety and upholding the values of the agricultural landscape. However, government agricultural policies have promoted an external model of development based on industrial monocultures, which generates socioeconomic and environmental instability, deficient models of agroproduction commercialisation and the impoverishment of agricultural landscapes. This article details the case of 60 farms from 22 communities in the municipality of Buenos Aires, in the South Pacific region of Costa Rica, where biological/physical, socioeconomic, marketing and governance issues of a Multifunctional and Territorialized Agrifood System have been characterized based on the family unit of production. In addition, a differentiation was made between peasant and indigenous farmers as their cultural backgrounds may then lead to their adopting different attitudes and distinct actions. By analysing the productive diversification of the models, the behaviour of the local marketing channels and their associative potential, the socio-ecological characteristics of the region were identified, including the strengths and weaknesses that should influence the model of agroproductive development and regional governance.
... In this application, green infrastructure can especially play an essential role in the protection of biodiversity in industrialized countries, as shown by the deployment of public policies for green and blue infrastructure worldwide (Linehan et al., 1995). Globally, the International Union for Conservation of Nature (IUCN) promotes green infrastructure as a key spatial planning tool for nature conservation (Bennett, 2003;Hilty et al., 2020). The concept of ecological connectivity is also implicit in several international conventions such as the Ramsar convention (1971) and the Bern convention (1979), European agreements (habitats and species directive) and related EU policy implementation (Natura 2000). ...
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Artificial light at night (ALAN) has been massively deployed worldwide and has become a major environmental pressure for biodiversity, especially contributing to habitat loss and landscape fragmentation. To mitigate these latter, green and blue infrastructure policies have been developed throughout the world based on the concept of ecological networks, a set of suitable interconnected habitats. However, currently, these nature conservation policies hardly consider the adverse effects of ALAN. Here, we promote the integration of darkness quality within the ’green and blue infrastructure’, to implement a ‘dark infrastructure’. Dark infrastructure should be identified, preserved and restored at different territorial levels to guarantee ecological continuities where the night and its rhythms are as natural as possible. For this purpose, we propose an operational 4-steps process that includes 1) Mapping of light pollution in all its forms and dimensions in relation to biodiversity, 2) Identifying the dark infrastructure starting or not from the already identified green/blue infrastructure, 3) Planning actions to pre- serve and restore the dark infrastructure by prioritizing lighting sobriety and not only energy saving, 4) Assessing the effectiveness of the dark infrastructure with appropriate indicators. Dark infrastructure projects have already been created (for example in France and Switzerland) and can serve as case studies for both urban and natural areas. The deployment of dark infrastructure raises many operational and methodological questions and stresses some knowledge gaps that still need to be addressed, such as the exhaustive mapping of light pollution and the characterization of sensitivity thresholds for model species.
... However, the use of these key terms in different disciplines, often not clearly defined, lead to misunderstanding and linguistic and semantic uncertainty. To overcome this, in 1999 the IUCN produced a monographic work on landscape linkages [17] which contained a review of the new key concepts that in recent years were emerging in the HF arena, to standardize the new language. Therefore, following a problem-solving approach [18], (i) the conservation problem (due to HF) was identified, (ii) solutions were developed, and (iii) planning and project strategies started. ...
...  "stepping stones": One or more separate patches of habitat in the intervening space between ecological isolates, that provide resources and refuge that assist animals to move through the landscape [17];  "habitat corridors": A linear strip of habitat that provides a continuous (or near continuous) pathway between two patches. This term has no implications about its relative use by animals [10,11,17];  "landscape connectivity": the process aimed to counter the adverse effects of HF; landscape connectivity depends on the availability and arrangement of suitable habitats [12,13];  "landscape continuity": the ability to allow the dynamics of species and individuals: two habitat patches are continuous if they allow the dispersion of individuals or propagules between patches [17];  "landscape contiguity": the physical component of the landscape connectivity; two habitat patches are contiguous if they are adjacent to each other [17];  "habitat linkages": an arrangement of habitats (not necessarily linear or continuous) at a local scale that enhances the movement of animals and plant propagules [17];  "landscape linkages": an arrangement of habitats (not necessarily linear or continuous) at the landscape scale that enhances the movement of animals and plant propagules [17];  "connectivity conservation": the action of individuals, communities, institutions, and businesses to maintain, enhance, and restore ecological flows, species movement, and dynamic processes across intact and fragmented environments [23];  "ecological network planning": an interconnected system of habitats whose biodiversity needs to be safeguarded. ...
...  "stepping stones": One or more separate patches of habitat in the intervening space between ecological isolates, that provide resources and refuge that assist animals to move through the landscape [17];  "habitat corridors": A linear strip of habitat that provides a continuous (or near continuous) pathway between two patches. This term has no implications about its relative use by animals [10,11,17];  "landscape connectivity": the process aimed to counter the adverse effects of HF; landscape connectivity depends on the availability and arrangement of suitable habitats [12,13];  "landscape continuity": the ability to allow the dynamics of species and individuals: two habitat patches are continuous if they allow the dispersion of individuals or propagules between patches [17];  "landscape contiguity": the physical component of the landscape connectivity; two habitat patches are contiguous if they are adjacent to each other [17];  "habitat linkages": an arrangement of habitats (not necessarily linear or continuous) at a local scale that enhances the movement of animals and plant propagules [17];  "landscape linkages": an arrangement of habitats (not necessarily linear or continuous) at the landscape scale that enhances the movement of animals and plant propagules [17];  "connectivity conservation": the action of individuals, communities, institutions, and businesses to maintain, enhance, and restore ecological flows, species movement, and dynamic processes across intact and fragmented environments [23];  "ecological network planning": an interconnected system of habitats whose biodiversity needs to be safeguarded. The geometry of the network has a structure based on the recognition of core areas, buffer zones and corridors that allow the exchange of individuals to reduce the extinction risk of local populations [14,23]. ...
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In this work, we analyzed the temporal trends of nine selected key terms used in the habitat fragmentation arena, quantifying their number (and frequency) of recurrence on Web of Science from 1960 to 2020. The most used key (focal) terms ("stepping stones", "habitat corridors", "landscape connectivity"), showed a progressive increase from 1981 to 2020, with "landscape connectivity" showing the highest increase in frequency in the last decade (2011-2020). Among the key secondary terms (recurring < 5%), although "corridors", "continuity", and "contiguity" showed a slight growth over the decades, "connectivity conservation" showed the most significant increase. This last landscape-related term recently replaced other local-scale concepts (as "stepping stones" and "corridors") as a consequence of a change of perspective. Conversely, "ecological network planning", used in landscape planning and less in conservation biology, showed a comparable fewer recurrence. This gap in recurrences could be due to a bias in our research approach, as Web of Science is a search engine that does not intercept grey literature (as plans and reports) drawn up by Public Agencies which rarely appears in scientific journals.
... Connectivity among green spaces affects the persistence of urban biodiversity (Bennett 2003). Connectivity usually has a positive (increase dispersal potential) impact on biodiversity, although adverse effects (movement of pests and enemies) can depress this advantage (Collinge 2009). ...
... For example, these smaller areas have a relatively large edge/center ratio, affecting their quality, favoring species that can persist in those changed edge spatial conditions. These related problems influencing biodiversity in urban green spaces have led to an interest in generating corridors or additional ''stepping stone'' green parcels to increase conditions that favor higher biodiversity (Bennett 2003;Collinge 2009). These types of connections may be more easily designed in new cities, where urban planning that emphasizes biodiversity can be included from the start of the process. ...
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ContextLarge cities contain different sizes and distributions of green spaces in a sea of buildings and roads. This urban landscape establishes habitats for different species that migrant through or persist in cities.Objectives To describe and analyze how green spaces patterns differ in large cities by using new mapping methods. This tool helps urban planning for land use decisions.Methods Using Patch Analyst Metrics, we propose a new method to analyze the current spatial arrangement of green spaces in Mexico City and New York City, long-established urban areas, as case studies.ResultsThe two cities differ in the number, size, and spatial distribution of green spaces. Mexico City has high numbers of large green spaces for native species habitat, but most of them are in a cluster in the south. In New York City, large spaces are distributed scattered throughout the whole territory, but New York City has much small areas than Mexico City. This spatial analysis shows areas for connectivity among existing green spaces that can improve the dispersal of many taxa of plants and animals. However, ecological planning must vary between the cities; no single generalization is appropriate.Conclusions Much data are available on the potential dispersal of species through cities, but a easily applied framework for understanding the existing habitat distribution is needed for future decisions. The results suggest mapping mechanisms can help to increase plant and animal movement patterns. However, these older cities have idiosyncratic starting points that must be the basis of future improvements.
... Thus, the more connected a patch is, the richer its biodiversity should be. Identifying the main reservoirs and corridors for species movement, as well as the obstacles to the functioning of ecological continuities, is important because connections are the basis on which policies for biodiversity preservation are founded to manage territorial development (Bennett, 2003). ...
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At the landscape level, intensification of agriculture, fragmentation, and destruction of natural habitats are major causes of biodiversity loss that can be mitigated at small spatial scales. However, the complex relationships between human activities, landscapes, and biodiversity are poorly known. Yet, this knowledge could help private stakeholders managing seminatural areas to play a positive role in biodiversity conservation. We investigated how water‐abstraction sites could sustain species diversity in vascular‐plant communities and two taxonomic groups of insect communities in a fragmented agricultural landscape. Landscape‐scale variables (connectivity indices and surrounding levels of herbicide use), as well as site‐specific variables (soil type for vascular plants, floral availability for Rhopalocera, and low herbaceous cover for Orthoptera), were correlated to structural and functional metrics of species community diversity for these taxonomic groups, measured on 35 industrial sites in the Ile‐de‐France region in 2018–2019. Rhopalocera and Orthoptera consisted essentially of species with a high degree of dispersal and low specialization, able to reach the habitat patches of the fragmented landscape of the study area. Sandy soil harbored more diverse vascular‐plant communities. Plant diversity was correlated to a greater abundance of Rhopalocera and a lower richness of Orthoptera. Increasing landscape connectivity was related to higher abundance of plants and Rhopalocera, and a higher evenness index for Orthoptera communities. Higher levels of herbicide use were related to a decrease in the biodiversity of plants and Rhopalocera abundance. High levels of herbicide favored high‐dispersal generalist plants, while high levels of connectivity favored low‐dispersal plants. Specialist Orthoptera species were associated with low herbaceous cover and connectivity. Water‐abstraction sites are valuable seminatural habitats for biodiversity. Changing intensive agricultural practices in surrounding areas would better contribute to conserving and restoring biodiversity on these sites. Landscape connectivity has a positive effect on plant and insect species community diversity on water‐abstraction sites; Level of herbicide treatments on crops in the surrounding landscape has a negative effect on species diversity of flora and Rhopalocera harbored by these industrial sites; and Improving landscape connectivity around these sites can enhance their role as seminatural habitats for biodiversity, especially in a less‐intensive agricultural context.
... Por último, la fragmentación fue alta para la mayoría de los hábitats a excepción de las unidades de hábitat CFL (La Grulla), COE (San Antonio de Murillos) y PCC (El Potrero), ya que estas coberturas se encuentran solo en una localidad y solo se encontró un parche de cada una. A pesar de tener una fragmentación elevada la unidad de hábitat PEL, que fue la tercera cobertura con más parches (tres) y ocupando el quinto lugar de porción de área (8.77%), tiene una conectividad importante en el sistema, permitiendo que las poblaciones sean dinámicamente viables; indicando con ello, que el tamaño de los parches son pequeños y, por tanto, el riesgo de extinción de las poblaciones en este tipo de coberturas es más alto (Bennet, 2003). ...
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Una propuesta de plan de manejo para la trucha endémica Oncorhynchus mykiss nelsoni en los arroyos de la cuenca del río Santo Domingo, Baja California, México fue generada con base en información documentada en las últimas tres décadas y la aplicación del modelo FPEIR (fuerzas motrices, presión, estado, impacto y respuesta). Esta subespecie catalogada en protección especial por la Norma Oficial Mexicana 059-2010 debido a su distribución confinada a los arroyos entre los 560 y 2,100 metros de altitud, enfrenta actualmente amenazas por diversas actividades antropogénicas y naturales (cambio climático). El estado actual de conservación poblacional de la trucha y sus hábitats fueron evaluados de manera integral mediante el análisis de la composición fisicoquímica del agua, el caudal de los arroyos, la distribución y abundancia poblacional, y los indicadores de la ecología de paisaje (unidades de hábitat, proporción de área por clase [CAP] y número de parches [PN]). Las fuerzas motrices, presión, impacto y respuesta se obtuvieron mediante un análisis documental, observaciones de campo, un análisis de amenazas y un análisis de riesgo de cada especie íctica exótica identificada cuenca abajo. La principal amenaza encontrada mediante el análisis de amenazas fue la reducción en los regímenes de flujo de los arroyos, principalmente debido al desvío de flujo del caudal para irrigación agrícola en los valles costeros de Camalú y Vicente Guerrero, y, en segundo lugar, el futuro declive poblacional de O. m. nelsoni, principalmente por el aumento de la temperatura en los arroyos por efecto del cambio climático global, lo cual promovería la dispersión de peces exóticos como Lepomis cyanellus y Gambusia affinis, hacia los sitios de menor elevación en la distribución de la trucha endémica en la cuenca del río Santo Domingo (arroyos San Antonio de Murillos, La Zanja y El Potrero), generando desplazamiento arroyo arriba de esta última. Las propuestas de manejo aportadas por esta investigación fueron la determinación del caudal ecológico en la cuenca del río Santo Domingo, la capacidad de carga ganadera para la conservación de la localidad La Grulla, y la propuesta de la localidad tipo (arroyo San Antonio de Murillos en Rancho San Antonio) sea considerada como un área de reguardo y conservación de germoplasma endémico de esta trucha bajacaliforniana, y finalmente, la proyección de un plan de mitigación para el acondicionamiento de los hábitats en la localidad tipo ante el inminente calentamiento global.