scholarly journals Bryophyte communities along horizontal and vertical gradients in a human-modified Atlantic Forest remnant

Botany ◽  
2013 ◽  
Vol 91 (3) ◽  
pp. 155-166 ◽  
Author(s):  
Mércia P.P. Silva ◽  
Kátia C. Pôrto
Keyword(s):  
Atlantic Forest ◽  
Environmental Heterogeneity ◽  
Vertical Gradient ◽  
Horizontal Gradient ◽  
Landscape Characteristics ◽  
Host Trees ◽  
Forest Remnant ◽  
Significant Difference ◽  
Edge Distance ◽  
Vertical Gradients

We compared the richness, diversity, and composition of epiphytic bryophytes in a Brazilian Atlantic Forest remnant along zones of height within host trees (vertical gradient) and edge to interior (horizontal gradient). We established five classes of edge distance, and within each one, three host trees were selected (15 in total). Samples were collected in five height zones within host trees from the base to the top. The highest average values of richness and diversity were found in the trunk zone. There was no significant difference of bryophyte total richness and diversity along edge distance and vertical zones. However, the guilds of light tolerance displayed particularities regarding vertical zonation. Shade epiphytes decreased significantly along vertical gradients, whereas sun epiphytes increased, demonstrating a compositional vertical stratification within host trees. Thus, bryophyte distribution in both understories and canopies is more related to microenvironmental conditions than landscape characteristics such as edge distance. Moreover, the features of the Atlantic Forest associated with the environmental heterogeneity of the remnant may play an important role in the lack of gradient in species' composition from the edge to the interior of the forest.

GRAVITY GRADIENTS AND THE INTERPRETATION OF THE TRUNCATED PLATE

Geophysics ◽  
1976 ◽  
Vol 41 (6) ◽  
pp. 1370-1376 ◽  
Author(s):  
John M. Stanley ◽  
Ronald Green
Keyword(s):  
Hilbert Transform ◽  
Theoretical Data ◽  
Vertical Gradient ◽  
Density Contrast ◽  
Horizontal Gradient ◽  
Gravity Gradients ◽  
Gravity Method ◽  
Commercially Important ◽  
Dip Angle ◽  
Vertical Gradients

The truncated plate and geologic contact are commercially important structures which can be located by the gravity method. The interpretation can be improved if both the horizontal and vertical gradients are known. Vertical gradients are difficult to measure precisely, but with modern gravimeters the horizontal gradient can be measured conveniently and accurately. This paper shows how the vertical gradient can be obtained from the horizontal gradient by the use of a Hilbert transform. A procedure is then presented which easily enables the position, dip angle, depth, thickness, and density contrast of a postulated plate to be precisely and unambiguously derived from a plot of the horizontal gradient against the vertical gradient at each point measured. The procedure is demonstrated using theoretical data.

A commensal network of epiphytic orchids and host trees in an Atlantic Forest remnant: A case study revealing the important role of large trees in the network structure

2018 ◽  
Vol 44 (1) ◽  
pp. 114-125 ◽  
Author(s):  
Henrique G. S. Zotarelli ◽  
José M. P. Molina ◽  
José E. L. S. Ribeiro ◽  
Silvia H. Sofia
Keyword(s):  
Atlantic Forest ◽  
Network Structure ◽  
Epiphytic Orchids ◽  
Host Trees ◽  
Forest Remnant ◽  
Large Trees

Tortoise beetles of an Atlantic Forest remnant in south Minas Gerais, Brazil: host plants and life history

2021 ◽  
Vol 55 (1-2) ◽  
pp. 15-60
Author(s):  
Paula A. A. Gomes ◽  
Marcel G. Hermes ◽  
Flávia R. Fernandes ◽  
Fernando A. Frieiro-Costa
Keyword(s):  
Life History ◽  
Atlantic Forest ◽  
Host Plants ◽  
Minas Gerais ◽  
Forest Remnant

scholarly journals Landscape Characteristics Based on Effectiveness of Wildlife Crossing Structures in South Korea

2021 ◽  
Vol 13 (2) ◽  
pp. 675
Author(s):  
Hyunjin Seo ◽  
Chulhyun Choi ◽  
Kyeongjun Lee ◽  
Donggul Woo
Keyword(s):  
Landscape Management ◽  
Spatial Pattern Analysis ◽  
Extrinsic Factors ◽  
Intrinsic Factors ◽  
Landscape Characteristics ◽  
Crossing Structures ◽  
Significant Difference ◽  
Management Plans ◽  
Wildlife Crossing Structures ◽  
Surrounding Landscape

Roads are notable and responsible for the loss of biodiversity and disruption of wildlife habitats connectivity. Wildlife crossing structures (WCS) help wildlife move between habitats by connecting fragmented habitats. Their effectiveness is affected by various factors. Here, to identify methods for improving the effectiveness of wildlife crossing structures, we controlled the effect of intrinsic factors, such as size, that are difficult to improve in an already installed area, and then, evaluated the differences in extrinsic factors using 12 landscape characteristics. Our results show that 18 wildlife crossing structures were selected with propensity-score (PS) matching method. The surrounding landscape characteristics differed between high-effectiveness wildlife crossing structures and low-effectiveness wildlife crossing structures. Particularly, there was a significant difference between the ‘statutory protected area’ and the ‘edge’ index of the morphological spatial pattern analysis among the landscape characteristic variables derived within 1 km2 of wildlife crossing structures. We empirically demonstrate that characteristics around highly effective WCS, statutory protected areas are widely distributed, and the ratio of edge of MSPA is low (within 1 km2). Therefore, an important outcome of our research is the demonstration that management of WCS itself is important, but conservation of surrounding habitats and landscape management plans are also significant.

scholarly journals Bioprospection and characterization of the amylolytic activity by filamentous fungi from Brazilian Atlantic Forest

2017 ◽  
Vol 17 (3) ◽  
Author(s):  
Paula Zaghetto de Almeida ◽  
Marita Gimenez Pereira ◽  
Caio Cesar de Carvalho ◽  
Paulo Ricardo Heinen ◽  
Luciana Sobrani Ziotti ◽  
...  
Keyword(s):  
Filamentous Fungi ◽  
Atlantic Forest ◽  
Rhizopus Oryzae ◽  
Residual Activity ◽  
Brazilian Atlantic Forest ◽  
Tropical Environments ◽  
Aspergillus Brasiliensis ◽  
Significant Difference ◽  
Initial Ph ◽  
Ph Range

Abstract Filamentous fungi are widely diverse and ubiquitous organisms. Such biodiversity is barely known, making room for a great potential still to be discovered, especially in tropical environments - which are favorable to growth and species variety. Filamentous fungi are extensively applied to the production of industrial enzymes, such as the amylases. This class of enzymes acts in the hydrolysis of starch to glucose or maltooligosaccharides. In this work twenty-five filamentous fungi were isolated from samples of decomposing material collected in the Brazilian Atlantic Forest. The two best amylase producers were identified as Aspergillus brasiliensis and Rhizopus oryzae. Both are mesophilic, they grow well in organic nitrogen-rich media produce great amounts of glucoamylases. The enzymes of A. brasiliensis and R. oryzae are different, possibly because of their phylogenetical distance. The best amylase production of A. brasiliensis occurred during 120 hours with initial pH of 7.5; it had a better activity in the pH range of 3.5-5.0 and at 60-75°C. Both fungal glucoamylase had wide pH stability (3-8) and were activated by Mn2+. R. oryzae best production occurred in 96 hours and at pH 6.5. Its amylases had a greater activity in the pH range of 4.0-5.5 and temperature at 50-65ºC. The most significant difference between the enzymes produced by both fungi is the resistance to thermal denaturation: A. brasiliensis glucoamylase had a T50 of 60 minutes at 70ºC. The R. oryzae glucoamylase only had a residual activity when incubated at 50°C with a 12 min T50.

Differential impact of liana colonization on the leaf functional traits of co-occurring deciduous and evergreen trees

2021 ◽  
Author(s):  
vivek pandi ◽  
Kanda Naveen Babu
Keyword(s):  
Functional Traits ◽  
Tree Species ◽  
Dry Matter Content ◽  
Differential Impact ◽  
Deciduous Species ◽  
Evergreen Species ◽  
Leaf Functional Traits ◽  
Leaf Trait ◽  
Host Trees ◽  
Significant Difference

Abstract The present study was carried out to analyse the leaf functional traits of co-occurring evergreen and deciduous tree species in a tropical dry scrub forest. This study also intended to check whether the species with contrasting leaf habits differ in their leaf trait plasticity, responding to the canopy-infestation by lianas. A total of 12 leaf functional traits were studied for eight tree species with contrasting leaf habits (evergreen and deciduous) and liana-colonization status (Liana+ and Liana−). In the liana-free environment (L−), evergreen trees had significantly higher specific leaf mass (LMA) and leaf dry matter content (LDMC) than the deciduous species. Whereas, the deciduous trees had higher specific leaf area (SLA) and mass-based leaf nitrogen concentration (Nmass). The leaf trait-pair relationship in the present study agreed to the well-established global trait-pair relationships (SLA Vs Nmass, Lth Vs SLA, Nmass Vs Lth, Nmass Vs LDMC, LDMC Vs SLA). There was no significant difference between L+ and L− individuals in any leaf functional traits studied in the deciduous species. However, evergreen species showed marked differences in the total chlorophyll content (Chlt), chlorophyll b (Chlb), SLA, and LMA between L+ and L− individuals of the same species. Deciduous species with the acquisitive strategy can have a competitive advantage over evergreen species in the exposed environment (L−) whereas, evergreen species with shade-tolerant properties were better acclimated to the shaded environments (L+). The result revealed the patterns of convergence and divergence in some of the leaf functional traits between evergreen and deciduous species. The results also showed the differential impact of liana colonization on the host trees with contrasting leaf habits. Therefore, liana colonization can significantly impact the C-fixation strategies of the host trees by altering their light environment. Further, the magnitude of such impact may vary among species of different leaf habits. The increased proliferation of lianas in the tropical forest canopies may pose a severe threat to the whole forest carbon assimilation rates.

scholarly journals Spatial continuity of soil attributes in an Atlantic Forest remnant in the Mantiqueira Range, MG

2013 ◽  
Vol 37 (1) ◽  
pp. 68-77 ◽  
Author(s):  
Marcela de Castro Nunes Santos ◽  
José Marcio de Mello ◽  
Carlos Rogério de Mello ◽  
Léo Fernandes Ávila
Keyword(s):  
Atlantic Forest ◽  
Spatial Dependence ◽  
Soil Bulk Density ◽  
Exchange Capacity ◽  
Dependence Structure ◽  
Spatial Continuity ◽  
Soil Attributes ◽  
Forest Remnant ◽  
Spatial Dependence Structure

The spatial characterization of soil attributes is fundamental for the understanding of forest ecosystems. The objective of this work was to develop a geostatistical study of chemical and physical soil attributes at three depths (D1 - 0-20 cm; D2 - 20-50 cm; D3 - 50-100 cm), in an Experimental Hydrographic Micro-catchment entirely covered by Atlantic Forest, in the Mantiqueira Range region, Minas Gerais. All the considered variables presented spatial dependence structure in the three depths, and the largest degrees of spatial dependence were observed for pH in the three depths, soil cation exchange capacity potential in D3, soil organic matter in D1 and D3 and clay and soil bulk density in D2. The method most used for the adjustments of semi-variogram models was the Maximum Likelihood and the most selected model was the Exponential. Furthermore, the ordinary kriging maps allowed good visualization of the spatial distribution of the variables.

scholarly journals Effects of bamboo dominance and palm-heart harvesting on the phylogenetic structure of the seed and seedling communities in an old-growth Atlantic Forest

2017 ◽  
Vol 33 (5) ◽  
pp. 309-316
Author(s):  
Daniella Schweizer ◽  
Débora Cristina Rother ◽  
Ana Elena Muler ◽  
Ricardo Ribeiro Rodrigues ◽  
Marco Aurélio Pizo ◽  
...  
Keyword(s):  
Functional Diversity ◽  
Atlantic Forest ◽  
Time Frame ◽  
Seed Rain ◽  
Old Growth ◽  
Phylogenetic Structure ◽  
Palm Heart ◽  
Forest Remnant ◽  
Before And After ◽  
Seedling Community

Abstract:A comprehensive assessment of the effect of disturbances on tropical and subtropical forests is needed to better understand their impacts on forest structure and diversity. Although taxonomic and functional diversity measures have been successfully adopted in this context, phylogenetic diversity metrics are still poorly explored. We compared the phylogenetic structure of the seed rain and regenerating seedling community in patches of an old-growth Atlantic Forest remnant dominated or not by a ruderal bamboo species, Guadua tagoara. We sampled those patches before and after illegal harvesting of the palm Euterpe edulis thus assessing if the harvesting led to changes in the phylogenetic structure of the seed rain and the regenerating community in both patches. Bamboo-dominated patches showed a significantly higher presence of species in the seed rain that were more distantly related to each other in the phylogeny than expected by chance compared with patches without bamboos, but this difference disappeared after palm-heart harvesting. Contrary to what we expected, we did not find significant changes in the phylogenetic structure of seedlings before or after palm-heart harvesting. The phylogenetic structure at the tips of the phylogeny was random overall. The maintenance of a higher presence of far relatives in the phylogeny of the seedling community suggests, assuming trait conservatism, that despite bamboo dominance and palm-heart harvesting, functional diversity is being preserved at least in the early regenerating stages and in the time frame of the study. However, higher presence of pioneer taxa after palm-heart harvest indicates that this disturbance may lead old-growth areas to earlier successional stages.

A Large Annual Cycle in Ozone above the Tropical Tropopause Linked to the Brewer–Dobson Circulation

2007 ◽  
Vol 64 (12) ◽  
pp. 4479-4488 ◽  
Author(s):  
William J. Randel ◽  
Mijeong Park ◽  
Fei Wu ◽  
Nathaniel Livesey
Keyword(s):  
Annual Cycle ◽  
Seasonal Cycle ◽  
Annual Variation ◽  
Lower Stratosphere ◽  
Vertical Gradient ◽  
Relative Amplitude ◽  
Vertical Layer ◽  
Satellite Measurements ◽  
Tropical Tropopause ◽  
Vertical Gradients

Abstract Near-equatorial ozone observations from balloon and satellite measurements reveal a large annual cycle in ozone above the tropical tropopause. The relative amplitude of the annual cycle is large in a narrow vertical layer between ∼16 and 19 km, with approximately a factor of 2 change in ozone between the minimum (during NH winter) and maximum (during NH summer). The annual cycle in ozone occurs over the same altitude region, and is approximately in phase with the well-known annual variation in tropical temperature. This study shows that the large annual variation in ozone occurs primarily because of variations in vertical transport associated with mean upwelling in the lower stratosphere (the Brewer–Dobson circulation); the maximum relative amplitude peak in the lower stratosphere is collocated with the strongest background vertical gradients in ozone. A similar large seasonal cycle is observed in carbon monoxide (CO) above the tropical tropopause, which is approximately out of phase with ozone (associated with an oppositely signed vertical gradient). The observed ozone and CO variations can be used to constrain estimates of the seasonal cycle in tropical upwelling.

scholarly journals Amphibians and reptiles of the Parque Estadual Turístico do Alto Ribeira (PETAR), SP: an Atlantic Forest remnant of Southeastern Brazil

2010 ◽  
Vol 10 (4) ◽  
pp. 257-274 ◽  
Author(s):  
Cybele de Oliveira Araujo ◽  
Thais Helena Condez ◽  
Rafael Parelli Bovo ◽  
Fernanda da Cruz Centeno ◽  
Amom Mendes Luiz
Keyword(s):  
Atlantic Forest ◽  
Legal Protection ◽  
Sao Paulo ◽  
Southeastern Brazil ◽  
Mountain Range ◽  
São Paulo ◽  
The South ◽  
Paulo State ◽  
Forest Remnant ◽  
São Paulo State

The herpetofauna of São Paulo State, Brazil, can be characterized as the most well-known in the country. However, despite the large number of studies in this area, there are still many sampling gaps within biomes such as the Atlantic Forest that are considered global conservation priorities due to the high rate of endemism and human disturbance. As a result of political and historical pressure, this biome has been reduced to less than 12% of its original extent and, despite its importance for global biodiversity conservation, only a small percentage of its original vegetation cover (1%) has some form of legal protection. This is the case of the Parque Estadual Turístico do Alto Ribeira (PETAR) which, together with the Parque Estadual de Intervales, Parque Estadual Carlos Botelho and Mosaico de Unidades de Conservação de Jacupiranga, forms of an ombrophilous forest continuum of 360 thousand ha in the south of São Paulo State. This study presents a list of amphibians and reptiles from the PETAR, with information on the local distribution and habitat use of the species. The survey was conducted from October to December 2009, completing a total of 15 sampling days using four complementary methods of active sampling: visual encounters, auditory encounters, searches by car and incidental encounters. We recorded a total of 91 species belonging to 53 genera and 24 families. This high diversity can be attributed to the existence of a wide variety of habitats and microhabitats in this region, such as the various aquatic sites used by many species of anuran amphibians. Moreover, the PETAR features a large altitudinal gradient (80 - 1,160 m elevation) that gives a large climatic, geological and hydrological heterogeneity to the area. This inventory is an important contribution to the expansion of knowledge about these assemblages in the Atlantic Forest to the south of Serra de Paranapiacaba mountain range, and provides support for the conservation of these groups in São Paulo State.

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