scholarly journals Influencia de microhábitats en el desempeño de especies herbáceas en áreas de bosque maduro y secundario en la región semiárida de Brasil

2015 ◽  
Vol 63 (2) ◽  
pp. 357 ◽  
Author(s):  
Juliana Ramos de Andrade ◽  
Kleber Andrade da Silva ◽  
Josiene Maria Fraga dos Santos ◽  
Danielle Melo dos Santos ◽  
Thiago Pereira Guerra ◽  
...  

<p>The conditions for plant establishment in mature forest are different from those found in disturbed areas. In dry environments, the herbaceous cover is the most important in the recolonization of deforested areas. It can, therefore, act as an ideal biological group for assessing how changes in habitat heterogeneity affect the resilience of dry forests. The aim of this research was to evaluate whether natural regeneration of the herbaceous stratum differed between areas of mature and secondary forest of Caatinga and to describe this process. The study took place in the Brazilian semiarid region during the rainy season 2011 (January to August), where fifty 1m² plots were set up, 25 allocated to the microhabitat established as “between canopies” and 25 to the microhabitat “under the canopy”. The herbaceous species selected for the study were <em>Delilia biflora</em> (Asteraceae), <em>Gomphrena vaga</em> (Amaranthaceae) and <em>Pseudabutilon spicatum</em> (Malvaceae), abundant species occurring in both areas. All individuals from the selected populations were counted, marked with sequential numbers, and the height of the stem was measured. Differences between areas, and in size and survival between microhabitats, were found only for the first two species. Fruit production was higher in the mature forest for the three species. The study concluded that: 1. The effect of the microhabitats “between canopies” and “under the canopy” in mature and secondary forest areas depends on the species considered; 2. Populations sensitive to light intensity differ in number of individuals, height and fruit production; and 3. The resilience of anthropogenic areas in semiarid environments can be characterized by the presence of spatial heterogeneity with regard to the emergence and survival of herbaceous seedlings, suggesting that the regeneration of disturbed areas may occur in patches. </p>

2016 ◽  
Vol 8 (1) ◽  
pp. 7
Author(s):  
MILENE DA ROCHA M. ◽  
CRISTIANO RIBEIRO F. ◽  
RANIERE GARCEZ C.S.

The Amazon has a great biodiversity, however in this regions some locations still without no research, showing the need for studies in this localities. The lack of information about the diversity of frogs and the speed of change in the landscape that have been taking place on the planet, demonstrates the urgent need to preserve the remaining resources. In this adverse scenario, live frogs that are sensitive to changes in natural forest areas, and are recognized as Bioindicator of environmental integrity. The present study had scoped to do a survey of the anuran species in a country area, near to the city of Porto Velho (RO). This land, is formed by two separate areas, one classified as secondary forests and the other as pasture area. The sampling was carried out from January to may 2012, using tools and techniques for catch in the night delimited by time, pitfall traps and frogs occasional meetings Were captured 63 specimens of Anurans, distributed in six families, where the richest in species were the Leptodactylidae (n = 6), Hylidae (n = 5), Bufonidae (n = 4), Microhylidae (n = 2), Brachycephalidae (n = 2) and Aromobatidae (n = 2), totaling 21 species identified.The most abundant species were the Leptodactylus chaquensis (n = 12) and Leptodactylus andreae (n = 8). The pasture area exhibited the greatest number of individuals captured with 65.07% of all frogs collected.


2020 ◽  
Vol 52 (992) ◽  
pp. 57-70
Author(s):  
Giovani Hernández-Canchola ◽  
Livia León-Paniagua

Abstract The little yellow-shouldered Mesoamerican bat, Sturnira parvidens Goldman, 1917, is a medium-sized yellow-shouldered bat with no tail, a vestigial uropatagium, and reddish or yellowish patches on the shoulders. It lives in tropical habitats associated with lower and mid-elevations from northern Costa Rica to Mexico, and it is one of 24 described species in the genus Sturnira. Although S. parvidens is more common in disturbed areas because it mainly feeds on pioneer plants, it uses day roosts located in mature forest or in areas with advanced successional stages. It is an abundant species and is listed as “Least Concern” by the International Union for Conservation of Nature and Natural Resources.


2013 ◽  
Vol 85 (3) ◽  
pp. 1127-1139 ◽  
Author(s):  
Paulo C.M.D. Mesquita ◽  
Daniel C. Passos ◽  
Sonia Z. Cechin

The choice of sampling methods is a crucial step in every field survey in herpetology. In countries where time and financial support are limited, the choice of the methods is critical. The methods used to sample snakes often lack objective criteria, and the traditional methods have apparently been more important when making the choice. Consequently researches using not-standardized methods are frequently found in the literature. We have compared four commonly used methods for sampling snake assemblages in a semiarid area in Brazil. We compared the efficacy of each method based on the cost-benefit regarding the number of individuals and species captured, time, and financial investment. We found that pitfall traps were the less effective method in all aspects that were evaluated and it was not complementary to the other methods in terms of abundance of species and assemblage structure. We conclude that methods can only be considered complementary if they are standardized to the objectives of the study. The use of pitfall traps in short-term surveys of the snake fauna in areas with shrubby vegetation and stony soil is not recommended.


HortScience ◽  
2019 ◽  
Vol 54 (9) ◽  
pp. 1501-1508 ◽  
Author(s):  
Jackson Teixeira Lobo ◽  
Ítalo Herbert Lucena Cavalcante ◽  
Augusto Miguel Nascimento Lima ◽  
Yuri Alysson Carvalho Vieira ◽  
Pedro Igor Rodrigues Modesto ◽  
...  

Adequate nutritional status is fundamental for the fruiting process of mango trees (Mangifera indica L.). In this context, plant biostimulants are substances that promote physiological and nutritional changes, benefiting production. The present study evaluated the effect of biostimulants on the nutritional status and fruit production of ‘Kent’ mango trees. The experiment was carried out in the Brazilian semiarid region over 2 consecutive years, 2016 and 2017. Leaf treatments with biostimulants were applied in three phases (preflowering, beginning of flowering, and full flowering) during both seasons. The treatments were as follows: T1) control (without biostimulants); T2) biostimulants containing nutrients and L-α-amino acids; T3) biostimulants containing nutrients and Lithothamnium algae extract; T4) biostimulants containing nutrients and sucrose; and T5) biostimulants containing nutrients, free amino acids, and Lithothamnium algae extract. The results show that there was no effect of the biostimulants for chlorophyll a, b, and total indices or for total leaf soluble carbohydrates. Some of the treatments affected the leaf concentrations of N, K, Mn, Fe, and Zn, whereas only T2 in 2016 and T5 in 2017 increased the number of fruits per panicle if compared with nontreated plants. In 2016, the production per tree was higher in T5 compared with the other treatments, whereas it was greater in 2017 in both T2 and T5 with increases of 37.4 and 23.1 kg per tree, respectively, compared with the control treatment. Biostimulants containing soluble nutrients, L-α-amino acids, free amino acids, and Lithothamnium algae extract benefit the nutritional status and increase the fruit production of mango ‘Kent’.


Author(s):  
M.D. Wildsmith ◽  
I.C. Potter ◽  
F.J. Valesini ◽  
M.E. Platell

Benthic macroinvertebrates were sampled seasonally in the subtidal and upper and lower swash zones at two sites in each of six nearshore habitat types on the lower west coast of Australia. The habitat types, which differed mainly in the extent of their exposure to wave activity and whether sea grass and/or nearshore reefs were present, had been distinguished quantitatively using values for a suite of seven statistically-selected enduring environmental characteristics (Valesini et al., 2003). The core samples yielded 121 species representing eight phyla, among which the Polychaeta, Malacostraca and Bivalvia were the most speciose classes, contributing ∼38, 23 and 10%, respectively, to the total number of individuals. The total number of species and mean density of macroinvertebrates at the most protected habitat type (1), i.e. 70 and 209·2 individuals 0·1 m−2, respectively, were far greater than in any other habitat type. Habitat type influenced species composition to a greater extent than either zone or season. Furthermore, the extents of the differences among the species compositions of the six habitat types statistically matched the extents of the differences among the values for the suite of enduring environmental characteristics that distinguished each of those habitat types. Overall, the species composition at habitat type 1 was the most distinct, containing five abundant species of polychaetes that were adapted to deposit-feeding in calm waters with high levels of organic material and which were rare in all other habitat types. In contrast, the fauna at the most exposed habitat type was characterized by four crustacean species and a species of bivalve and polychaete, whose mobility and tough external surface facilitated their survival and feeding in turbulent waters. The zonal differences in faunal compositions among habitat types were greatest in the case of the subtidal zone. The faunal compositions differed among zones and seasons only at the most protected habitat type.


2021 ◽  
Vol 14 ◽  
pp. 194008292110103
Author(s):  
Patrick Jules Atagana ◽  
Eric Moïse Bakwo Fils ◽  
Sevilor Kekeunou

We aimed to assess how bats are affected by habitat transformation by comparing bat assemblages in four habitat types: primary forest, secondary forest, cocoa plantations and human habitations in the Dja Biosphere Reserve of southern Cameroon. Bats were sampled in the four habitat types using mist nets. During 126 nights, a total of 413 bats were captured, belonging to four families, 16 genera and 24 species. Ninety three individuals (17 species) were captured in the primary forest, followed by plantations (105 individuals, 14 species), human habitations (159 individuals, 10 species), and secondary forest (55 individuals, eight species). Megaloglossus woermanni was recorded in all the four habitats, and was the most abundant species (105 individuals). The analysis of bat assemblage between habitat types showed a statistically significant difference in species composition. The distribution of the six most abundant species ( Epomops franqueti, Megaloglossus woermanni, Rousettus aegyptiacus, Dohyrina cyclops, Hipposideros cf. caffer and Hipposideros cf. ruber) was influenced by habitat types. Our results suggest that the decrease in species richness observed in disturbed habitats may be due to habitat perturbations of primary forest habitats. Therefore, it is important to examine the effects of habitat conversion at species level, as responses are often species-specific.


Author(s):  
Uemeson José dos Santos ◽  
Everardo Valadares de Sá Barretto Sampaio ◽  
Eunice Maia de Andrade ◽  
Alexandre de Siqueira Pinto ◽  
Bruno de Oliveira Dias ◽  
...  

2021 ◽  
pp. 1-12
Author(s):  
José Almir Cirilo ◽  
Alfredo Ribeiro Neto ◽  
Nyadja Menezes Rodrigues Ramos ◽  
Carla Fernanda Fortunato ◽  
Júlia Daniele Silva de Souza ◽  
...  

2018 ◽  
Vol 30 (0) ◽  
Author(s):  
Josiane Souza Santos ◽  
Nadson Ressyé Simões ◽  
Sérgio Luiz Sonoda

Abstract Aim: The objective of this study was to investigate the spatial and temporal variation of microcrustacean assemblages of a reservoir in the Brazilian semiarid region. Methods Physical and chemical water variables and samples of microcrustaceans were collected at eight sites of the reservoir between July 2013 and November 2014, in a total of seven campaigns. For this study, the reservoir was categorized in two compartments: lateral and central. Results Limnological variables showed significant temporal variation (PERMANOVA, Pseudo-F = 19.51, p = 0.001). Higher turbidity values and suspended solids were observed in the rainiest months, while during the dry months, we measured higher values of transparency, dissolved oxygen, and chlorophyll-a. It was not found significant spatial variation of limnological variables (PERMANOVA, Pseudo-F = 0.96; p = 0.394). During the study period, ten species were recorded: four Cladocera (Ceriodaphnia cornuta, Daphnia gessneri, Diaphanosoma birgei and Diaphanosoma spinulosum ) three Copepoda Calanoida (Argyrodiaptomus azevedoi, Notodiaptomus cearensis and Notodiaptomus iheringi) and three Copepoda Cyclopoida (Macrocyclops albidus, Thermocyclops minutus and Thermocyclops decipiens). The microcrustacean assemblages showed significant temporal variation (PERMANOVA, Pseudo-F = 4.34; p = 0.001) as well as significant spatial variation (PERMANOVA, Pseudo-F = 9.46; p = 0.001). The highest values of abundance and richness were observed in the lateral compartment, this result is mainly related to the presence of aquatic macrophytes in this region, because the analysis of partial RDA indicated that limnological variables explained only 11% of this variation (Pseudo-F = 2.08, p = 0.001). Conclusions The results suggest that the seasonality of the semiarid is an important factor in the temporal dynamics of the limnological variables, while the aquatic macrophytes play an important role in the spatial distribution of the microcrustacean assembly.


2014 ◽  
Author(s):  
Sergio Rosim ◽  
João Ricardo de Freitas Oliveira ◽  
Jussara de Oliveira Ortiz ◽  
Miguel Zanic Cuellar ◽  
Alexandre Copertino Jardim

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