scholarly journals Fragment shape and size, landscape permeability and fragmentation level as predictors of primate occupancy in a region of Brazilian Cerrado

2020 ◽  
Vol 42 ◽  
pp. e48339
Author(s):  
Thallita Oliveira Grande ◽  
Raony Macedo Alencar ◽  
Paulo Pinheiro Ribeiro ◽  
Fabiano Rodrigues Melo

Human activities result in the formation of a mosaic of forest patches within a non-habitat matrix. The response of the local biodiversity to changes in land-use may occur at different scales. It is important to evaluate the effects of the attributes of both the patches and the surrounding landscape on the occupancy of forest patches by animal populations. Here, we assessed the predictive potential of local (basal area, tree density), patch (size, shape) and landscape scale (total area of forest, number of patches, matrix permeability, patch proximity) variables on the occupancy of forest patches by the syntopic primates Alouatta caraya, Sapajus libidinosus and Callithrix penicillata in the city of Goiânia in the Cerrado region of central Brazil. We used playback to survey primate populations in 22 focal patches and assessed the landscape within a 1000 m buffer zone around each site. In A. caraya, occupancy was influenced by the shape of the focal patches, the amount of forest and fragmentation level of the landscape. Focal patch size and the permeability of the matrix were the principal determinants of the occupancy of S. libidinosus. None of the predictors influenced patch occupancy in C. penicillata, and the structure of the vegetation did not influence occupancy in any of the species. The preservation of as many forest patches as possible, both large and small, as well as gallery forests, and the enhancement of matrix permeability will be essential for the long-term conservation of the syntopic primates of the Cerrado of central Brazil.

CERNE ◽  
2015 ◽  
Vol 21 (1) ◽  
pp. 117-123 ◽  
Author(s):  
Fábio Venturoli ◽  
Augusto César Franco ◽  
Christopher William Fagg

In the Cerrado biome of Brazil, savannas and dry forests are intimately linked and form mosaics. These forests are composed of species of high commercial value, well accepted in the timber market, which causes intensive deforestation on the remaining vegetation. Thus, the management of these forests is an important alternative to reduce deforestation in the remaining vegetation. The objective of this study was to analyze the response of tree species in relation to silvicultural treatments of competition and liana cutting in a semi-deciduous forest in Central Brazil. The results showed that community basal area increased 24% over 4.8 years and the median periodic annual increment in diameter was about 20% higher in plots with silvicultural treatments: 2.9 mm.yr-1 in the control compared to 3.2 mm.yr-1 to 3.6 mm.yr-1 between treatments. This study demonstrated that it is possible to increase the rates of radial growth through silvicultural techniques.


2016 ◽  
Vol 8 (3) ◽  
pp. 360-369
Author(s):  
Devi A.G. PRASAD ◽  
Shwetha BHARATHI

Sacred groves are one of the finest examples of informal way of conserving the forest wealth. Baseline data collection of their diversity, distribution and regeneration capacity becomes necessary for the management and conservation of these undisturbed forest patches. In this context, the present investigation was carried out using random quadrat method in the sacred groves of Virajpet, Karnataka, India. A total of 132 tree species belonging to 113 genera and 45 families were identified within five sacred groves. Higher basal area (51.73-85.65 m2/ha) and tree density (453.33-515.9 individuals/ha) were observed as compared to other forests of Western Ghats region. The present investigation has revealed a healthy regeneration of tree species. Seedling and sapling composition differed to some extent from the mature tree species composition which could be used in predicting the future possibilities. Protection and conservation of such sacred groves should be of interest, for better regeneration of the rich diversity they harbour.


2017 ◽  
Vol 83 ◽  
pp. 1-14 ◽  
Author(s):  
Dharmalingam Mohandass ◽  
Mason J. Campbell ◽  
Alice C. Hughes ◽  
Christos Mammides ◽  
Priya Davidar

2005 ◽  
Vol 32 (3) ◽  
pp. 239-247 ◽  
Author(s):  
SIDDHARTHA B. BAJRACHARYA ◽  
PETER A. FURLEY ◽  
ADRIAN C. NEWTON

Community-based approaches to decision-making in the management of protected areas are increasingly being implemented in many areas. However information on the outcome of these approaches for conservation is often lacking. In this study, the effectiveness of community-based approaches for conservation of biodiversity was examined in Annapurna Conservation Area (ACA) (Nepal) through a combination of ecological assessments and social surveys undertaken both within and outwith ACA. Forest basal area and tree species diversity were found to be significantly higher inside ACA than in neighbouring areas outside. The mean density of cut tree stumps was significantly lower inside ACA, associated with a decline in use of fuelwood as an energy source over the past decade. Social surveys also indicated that wild animal populations have increased inside ACA since the inception of community-based conservation. Observations of animal track counts, pellet counts and direct observations of selected species such as barking deer (Muntiacus muntjak) and Himalayan tahr (Hemitragus jemlahicus) indicated higher abundances within ACA. The community-based management has been successful in delivering conservation benefits in ACA, attributable to changing patterns of resource use and behaviour among local communities, increased control of local communities over their local resources, increased conservation awareness among local people resulting from environmental education, and the development and strengthening of local institutions such as Conservation Area Management Committees (CAMC). However, these positive achievements are threatened by the current political instability in Nepal.


2005 ◽  
Vol 35 (10) ◽  
pp. 2521-2527 ◽  
Author(s):  
François Potvin ◽  
Normand Bertrand ◽  
Jean Ferron

The snowshoe hare (Lepus americanus Erxleben) is an important prey for many predators in the boreal forest. In this biome, clear-cut landscapes are generally large and consist of aggregated cutting blocks separated by narrow forest strips (typically 60–100 m wide). To identify attributes of forest strips that are important for snowshoe hares, we measured the use of strips using track counts over two winters in six clear-cut landscapes (23–256 km2) in south-central Quebec. Surveys were conducted in 20 riparian strips (RS), 20 upland strips (US), and 15 control sites (CO) at the periphery of clear-cut landscapes. Overall, 392 signs of hare presence were recorded along 50 km of transects. Snowshoe hares were present in one-third of the strips surveyed and were five times less abundant in US and RS than in CO. The species avoided strip edges. Hares were more common in the wider strips (>100 m), in the strips adjacent to residual forest patches (≥25 ha), or in those having a denser shrub canopy, which is often associated with a greater basal area in balsam fir (Abies balsamea (L.) Mill.). To maintain snowshoe hare at moderate densities in large clear-cut landscapes, we suggest leaving uncut forest strips >100 m wide in areas having a good shrub cover with presence of balsam fir.


2008 ◽  
Vol 86 (7) ◽  
pp. 692-699 ◽  
Author(s):  
Flavio Zanini ◽  
Anna Klingemann ◽  
Rodolphe Schlaepfer ◽  
Benedikt R. Schmidt

Species movement and occupancy of habitat patches are dependent on landscape permeability. Some land-use types (e.g., roads) may be barriers to animal movement. Analyses of the effect of landscape structure on patch occupancy usually use circular buffers around focal patches. The main assumption of this methodological approach is that species are affected by a particular landscape element equally in every direction from a given patch. This assumption is likely not to hold if animal movement is restricted by barriers because barriers reduce movement patterns and reshape the ideal circular buffer into a noncircular buffer. We developed a method to determine the effect of landscape variables on the distribution of two amphibian species that explicitly takes dispersal barriers into account. We extracted landscape variables within (i) circular buffers (CB) and (ii) barrier-based buffers (BBB). BBB were produced by reducing the boundaries of CB according to major impassable barriers. The BBB approach almost doubled the explained deviance of multiple regression models in comparison with the CB approach. Moreover, CB and BBB models included different predictor variables. We suggest that the BBB approach is more useful than the traditional CB analyses of species–habitat relationships because ecological barriers are explicitly taken into account.


1998 ◽  
Vol 28 (7) ◽  
pp. 1068-1072 ◽  
Author(s):  
Jukka Jokimäki ◽  
Esa Huhta ◽  
Juhani Itämies ◽  
Pekka Rahko

We studied the abundance of arthropods in relation to forest patch size, edge orientation, distance from the forest - open-land edge, and stand characteristics in pine-dominated forests in northern Finland. Arthropod samples were collected using the sweep-net method. The total catch of arthropods, catches from the field layer and deciduous shrubs, the numbers of flying arthropods, small (<1 mm) arthropods, and the numbers of seven different arthropod taxa (viz. Linyphiidae (Arachnida), Cicadellidae (Homoptera), Diptera, Brachycera (Diptera), Nematocera (Diptera), and Hymenoptera and Ichneumonidae (Hymenoptera)) were lower in large forest patches (>5 ha) than in small patches (5 ha). The edge orientation and the type of adjacent open area (clearcut area or treeless mire) had no impact on the abundance of arthopods in the patches. The distance from the forest edge affected the total abundance of arthropods, small arthropods, flying arthropods, and Coleoptera (especially Cantharidae) in that all decreased in number from the forest edge to the interior of the forest stand. The abundance of many arthropod taxa correlated positively with the numbers of saplings, deciduous shrubs, and spruces. It was clear that the existence of these vegetation characteristics mainly explained the observed differences in the abundance of arthropods between forest patches of different sizes and also between forest edges and stand interiors.


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