scholarly journals Towards quantifying changes in forest cover in the Araucaria forest-grassland mosaic in southern Brazil

Author(s):  
Daniela Piraquive Bermúdez ◽  
Martin Theuerkauf ◽  
Thomas Giesecke

AbstractQuantitative estimates of past vegetation cover are needed both regionally so human-landscape interactions can be better understood, and globally to evaluate the effects of changing vegetation cover on the climate system. Models reducing the bias in the pollen representation of vegetation cover have been developed in the temperate regions of the northern hemisphere, while experience applying them in other parts of the world is limited. The Araucaria forest-grassland mosaic of southern Brazil is an area where open and forested plant communities exist naturally and have changed their cover over time due to changing climate and human activities. Therefore, this area is of particular interest for such studies. Modern pollen and vegetation comparisons were carried out in two protected areas: Vila Velha State Park in Paraná state and Aparados da Serra National Park in Rio Grande do Sul. Vegetation mapping and analysis focused on Araucaria angustifolia as the characteristic tree of this vegetation type. In the Araucaria forest-grassland mosaic open vegetation and woodland change at a scale of hundreds of metres. These changes are difficult to capture based on pollen proportions in surface samples. While the abundance of Poaceae pollen is not a good indicator of locally open conditions, several pollen taxa can be used as indicators of the local vegetation cover. Pollen vegetation ratios (R-values) compare well between the two study regions, indicating that pollen production of individual species within the large plant families of Poaceae and Asteraceae are similar within the overall region. Araucaria angustifolia pollen is underrepresented with regards to its vegetation cover, while Poaceae are among the highest pollen producers in the region. Diverse woodland species other than A. angustifolia were grouped as one forest taxon and as the species composition of woodlands differed between the two study areas, so did the estimated pollen productivity of this group. It would be rewarding in future investigations to estimate pollen productivity for groups of trees with the same pollen dispersal syndrome. The application of pollen dispersal models designed for closed canopy in the protected areas was challenging. Further model development is required to deal with pollen released at different levels in semi-open vegetation types.

2011 ◽  
Vol 89 (12) ◽  
pp. 1214-1222 ◽  
Author(s):  
Ashley A.D. McLaren ◽  
Lenore Fahrig ◽  
Nigel Waltho

Previous studies suggest the gap in forest cover generated by roads contributes to the barrier effect of roads on movement of forest-dwelling small mammals. However, it is not known if vegetated medians of divided highways affect movement of small mammals by reducing the effective highway width. The purpose of our study was to determine whether the type of vegetation cover in the median (treed or grassy) or median width affects small-mammal crossings of divided highways. At 11 study sites varying in median cover type and width, we live-trapped small mammals next to one side of the highway and translocated them to the opposite side of the highway using a standardized translocation distance. In total, 24% of translocated individuals were recaptured on the side of the highway of initial capture, i.e., they had moved across the entire highway. This was significantly lower than what would have been expected in the absence of the highway (58%). The overall probability of recapturing a translocated individual was not significantly related to median cover type or width. Our results suggest that efforts to mitigate the barrier effect of highways on small mammals cannot be accomplished by altering median vegetation type and width.


Human Ecology ◽  
2021 ◽  
Author(s):  
Liz Alden Wily

AbstractI address a contentious element in forest property relations to illustrate the role of ownership in protecting and expanding of forest cover by examining the extent to which rural communities may legally own forests. The premise is that whilst state-owned protected areas have contributed enormously to forest survival, this has been insufficiently successful to justify the mass dispossession of customary land-owning communities this has entailed. Further, I argue that state co-option of community lands is unwarranted. Rural communities on all continents ably demonstrate the will and capacity to conserve forests – provided their customary ownership is legally recognized. I explore the property rights reforms now enabling this. The replication potential of community protected forestlands is great enough to deserve flagship status in global commitments to expand forest including in the upcoming new Convention on Biological Diversity (CBD).


Geomatics ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 335-346
Author(s):  
Do-Hyung Kim ◽  
Anupam Anand

Evaluation of the effectiveness of protected areas is critical for forest conservation policies and priorities. We used 30 m resolution forest cover change data from 1990 to 2010 for ~4000 protected areas to evaluate their effectiveness. Our results show that protected areas in the tropics avoided 83,500 ± 21,200 km2 of deforestation during the 2000s. Brazil’s protected areas have the largest amount of avoided deforestation at 50,000 km2. We also show the amount of international aid received by tropical countries compared to the effectiveness of protected areas. Thirty-four tropical countries received USD 42 billion during the 1990s and USD 62 billion during the 2000s in international aid for biodiversity conservation. The effectiveness of international aid was highest in Latin America, with 4.3 m2/USD, led by Brazil, while tropical Asian countries showed the lowest average effect of international aid, reaching only 0.17 m2/USD.


2011 ◽  
Vol 41 (3) ◽  
pp. 501-508 ◽  
Author(s):  
Ambroise Lycke ◽  
Louis Imbeau ◽  
Pierre Drapeau

Partial cuts are increasingly proposed to maintain habitats for species negatively affected by clearcutting, even if their benefits on nonpasserine birds and large mammals are still poorly documented. Our main objective was to evaluate effects of commercial thinning (CT) on spruce grouse ( Falcipennis canadensis L.), a game bird of the boreal forest. Because this species is known to be associated with a dense vegetation cover, we hypothesized that habitat use would be lower in treated sites. In spring 2006, we evaluated site occupancy in 94 forest stands (50 CT and 44 uncut stands) in Quebec by visiting each on three occasions during the breeding season (March–May). Additionally, during the molting period (May–July), we used radiotelemetry to monitor habitat use by 19 males. As compared with uncut stands, results show that a lower proportion of CTs were used in spring (39% versus 60%, after accounting for detection). During the molting period, CTs were also used less than expected according to their availability. The significant reduction of lateral and vertical forest cover in CT may explain these results. We conclude that even if CT is perceived beneficial for wildlife, it does not completely fulfill the needs of species associated with dense understory vegetation, such as spruce grouse.


1999 ◽  
Vol 29 (1) ◽  
pp. 106-114 ◽  
Author(s):  
Quanfa Zhang ◽  
Kurt S Pregitzer ◽  
David D Reed

The General Land Office (GLO) survey notes (1840-1856) were used to examine the interaction among natural disturbance, vegetation type, and topography in the presettlement forests of the Luce District, an ecological unit of approximately 902 000 ha in the Upper Peninsula of Michigan, U.S.A. The surveyors recorded 104 fire and 126 windthrow incidences covering 3.1 and 2.8% of the total length of the surveyed lines, respectively. The rotation periods over the entire landscape were 480 years for fire and 541 years for windthrow, but these varied with vegetation type and topographic position. Fire occurred more frequently on southerly aspects and at elevations where pinelands were concentrated. The density of windthrow events increased with elevation and slope, with the highest occurrence on westerly aspects. Based on the estimated rotation periods, we calculated that 7.5, 24.4, and 68.1% of the presettlement forest were in the stand initiation, stem exclusion, and old forest (including both understory reinitiation and old growth) stages, respectively. Pinelands and mixed conifers were the major components in both the stand initiation (34.5 and 31.1%) and the stem exclusion stage (20.9 and 39.8%), while mixed conifers (39.3%) and northern hardwoods (34.7%) were the major old-forest cover types. The diverse mosaic of various successional stages generated by natural disturbance suggests a "shifting-mosaic" landscape in this region.


2013 ◽  
Vol 61 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Ciro Alberto de Oliveira Ribeiro ◽  
Alberto Katsumiti ◽  
Patrícia França ◽  
Jocieli Maschio ◽  
Eliandra Zandoná ◽  
...  

Paranaguá bay is a complex estuary located in southern Brazil containing three protected areas listed by UNESCO. Historically, the estuary has been affected by urban, industrial, agricultural and harbor activities, and occasional accidents. Specifically, the explosion of the Chilean ship Vicuña in December 2004 spilled methanol and crude and fuel oils which affected both protected and non-protected areas. The present study sought to investigate the pollution threat to aquatic organisms in order to evaluate the potential effects of pollutants. One hundred and twenty adult fish Atherinella brasiliensis were collected from different sites within Paranaguá estuary, including the harbor and open ocean, during summer, autumn and winter of 2005. Among the biomarkers, the somatic index, chemical analysis of bile, biochemical, genetic and morphological parameters were considered. Chemical analysis of bile showed a continuous bioavailability of polycyclic aromatic hydrocarbons (PAHs) according to proximity to the harbor site. The histopathological findings have demonstrated aconsiderable incidence of severe pathologies in the liver and gills, corroborated by biochemical disturbances and genetic damage. These findings indicate that more studies are necessary to evaluate both water quality and fish health so as to permit a better analysis of the impact of pollution in Paranaguá estuary.


Author(s):  
A. Sokolov

This paper analyzes the patterns of anthropogenic transformation of landscapes in the Brest region, as measured by value indicators such as forest cover (and geo-ecological coefficient based on it), the density of rural population, the share of residential landscapes. Correlation between nature properties of landscapes underlying their classification, and these indicators was detected. It was found that the genera of landscapes, which represent the maximum disturbance, are secondary-moraine and moraine-outwash landscapes, the subgenera of landscapes are with a cover and a discontinuous cover of glacial sandy loams. The least disturbance is distinctive for secondary water-glacial and alluvial terraced landscapes and among genera – with superficial cover of water-glacial sands and with superficial bedding of peat and sand. The necessity of protected areas network optimization is shown. The results showed a significant imbalance between the ecological condition of the landscape which belong to certain classification groups and their representation in the protected areas system of the region. Landscapes with the worst ecological situation, as a rule, occupy a small proportion among all landscapes of protected areas. This case does not allow carrying out fully the tasks of protection and restoration of the diversity of ecosystems of the region. Among genera share of protected areas is much greater than the share of the region generally occupy wetland and floodplain landscapes. Moraine-outwash landscapes, characterized by a critical environmental condition are not represented in the protected areas system. Among subgenera areas in protected territories are far larger than in the region are characterized for landscapes with superficial stratification of peat and sand, considerably smaller – for landscapes with a cover of water-glacial sandy loams and loams, ecological condition of which is estimated as critical. Thus, the existing network of protected areas in Brest region needs to be optimized be including those genera and subgenera of landscapes, which are characterized by the worst environmental condition and restore these areas to natural communities.


2016 ◽  
Vol 24 (1) ◽  
pp. 157-163
Author(s):  
V. І. Nikolaichuk ◽  
M. М. Vakerich ◽  
M. V. Bilkey ◽  
O. P. Chechuy ◽  
I. Voloshchuk

Ukraine has transformed into one of the most environmentally dangerous countries in the world due to the high concentration of industrial production and agriculture and predatory use of natural resources. The current ecological situation in Ukraine is characterized by a deep ecological crisis, which is caused by the laws of operation of the command economy of the former USSR. The majority of the environmental and social indicators of Ukraine are among the worst in Europe. The Carpathian Mountains are among the most significant and interesting landscapes in Europe from the geological and geomorphological, scenic and biological perspectives. The giant arc of the Carpathians begins in southern Romania and passes through Ukraine, Slovakia, Poland, the Czech Republic and Hungary to Austria, crosses all Eastern and Central Europe. A third of the forest reserves of Ukraine are located in the Ukrainian Carpathians, at 53.5% the percentage of forest cover of the area is among the highest in the country. About 50% of the gene pool of Ukraine’s plants, many species of trees and medicinal plants grows there. The geographical location and large area of the rich natural heritage of the Carpathians have multifaceted importance for the conservation of biological, phytocoenotic and landscape diversity and maintaining the ecological balance in the central part of our continent. As with the Alps mountain range, this is an important ecological corridor between Western, Central and Eastern Europe, which promotes the migration of species and their spread into lowland landscapes. In order to preserve biodiversity an inventory of virgin forest ecosystems should be made and strict measures for their protection should be enforced. It is necessary to continue the practice of establishing bilateral areas in cross-border protected areas in order to combine efforts to solve pressing environmental challenges. Conservation of the Carpathians Biodiversity is an urgent problem. Structural changes in the economy of the region are expected to strengthen the recreational value of the Ukrainian Carpathians for the public not only in our country but also in Central and Eastern Europe, reducing the technogenic loading. International cooperation of all countries of the Carpathian region is imperative. The development of tourism in the Carpathians is highly promising, but this should be civilized tourism, taking into account the environmental sustainability of the recreational areas and protected areas. 


The Holocene ◽  
2007 ◽  
Vol 17 (1) ◽  
pp. 65-77 ◽  
Author(s):  
Welmoed Soepboer ◽  
Shinya Sugita ◽  
André F. Lotter ◽  
Jacqueline F.N. van Leeuwen ◽  
Willem O. van der Knaap

Author(s):  
P. Das ◽  
M. D. Behera ◽  
P. S. Roy

The impact of long term climate change that imparts stress on forest could be perceived by studying the regime shift of forest ecosystem. With the change of significant precipitation, forest may go through density change around globe at different spatial and temporal scale. The 100 class high resolution (60 meter spatial resolution) Indian vegetation type map was used in this study recoded into four broad categories depending on phrenology as (i) forest, (ii) scrubland, (iii) grassland and (iv) treeless area. The percentage occupancy of forest, scrub, grass and treeless were observed as 19.9&amp;thinsp;%, 5.05&amp;thinsp;%, 1.89&amp;thinsp;% and 7.79&amp;thinsp;% respectively. Rest of the 65.37&amp;thinsp;% land area was occupied by the cropland, built-up, water body and snow covers. The majority forest cover were appended into a 5&amp;thinsp;km&amp;thinsp;&amp;times;&amp;thinsp;5&amp;thinsp;km grid, along with the mean annual precipitation taken from Bioclim data. The binary presence and absence of different vegetation categories in relates to the annual precipitation was analyzed to calculate their resilience expressed in probability values ranging from 0 to 1. Forest cover observed having resilience probability (Pr) &amp;lt;&amp;thinsp;0.3 in only 0.3&amp;thinsp;% (200&amp;thinsp;km<sup>2</sup>) of total forest cover in India, which was 4.3&amp;thinsp;% &amp;lt;&amp;thinsp;0.5&amp;thinsp;Pr. Majority of the scrubs and grass (64.92&amp;thinsp;% Pr&amp;thinsp;&amp;lt;&amp;thinsp;0.5) from North East India which were the shifting cultivation lands showing low resilience, having their high tendency to be transform to forest. These results have spatial explicitness to highlight the resilient and non-resilient distribution of forest, scrub and grass, and treeless areas in India.


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