Brazilian forest producers have developed integrated management programs to increase the effectiveness of the control of leaf-cutting ants of the genera Atta and Acromyrmex. These measures reduced the costs and quantity of insecticides used in the plantations. Such integrated management programs are based on monitoring the ant nests, as well as the need and timing of the control methods. Chemical control employing baits is the most commonly used method, however, biological, mechanical and cultural control methods, besides plant resistance, can reduce the quantity of chemicals applied in the plantations.
Changes in the hydrological regime of the Lower São Francisco River, located in Northeastern Brazil have brought negative environmental impacts, jeopardizing the flora and fauna of a global biodiversity hotspot, due to implementation of hydroelectric power dams and surface water withdrawal for irrigation in public and private perimeters. Remnants of the riparian stratum associated to the riverbank destabilization in six fragments were studied by surveying trees, shrubs, herbs, and aquatic species. The calculation of the Factor of Safety (FS) was performed in order to understand the riverbank's stability related to soil texture and vegetation cover. An overall number of 51 botanic families distributed in 71 genera and 79 species were recorded, predominantly from the families Mimosaceae, Myrtaceae, and Fabaceae. The fragmented riparian vegetation is mostly covered by secondary species under a strong anthropogenic impact such as deforestation, mining and irrigation, with an advanced erosion process in the river margins. Strong species that withstand the waves present in the river flow are needed to reduce the constant landslides that are mainly responsible for the river sedimentation and loss of productive lands. A lack of preservation attitude among the local landholders was identified, and constitutes a continuing threat to the riparian ecosystem biodiversity.
A modelagem do risco espacial de incêndios florestais tem o objetivo de determinar as regiões mais susceptíveis ao fogo, baseando-se em variáveis que representam a facilidade de ignição e de propagação do fogo. Nesse contexto, utilizando-se das variáveis: sistema viário, densidade demográfica, uso e ocupação do solo, malha hidrográfica, inclinação e orientação das encostas, foram elaborados mapas de riscos preliminares, que, posteriormente à ponderações das mesmas pelo método AHP, foram integradas por meio da calculadora Raster em um mapa final de risco de incêndio florestal para o município de Inhambupe, Bahia, Brasil. Com base no modelo utilizado, 75,46% da área de estudo apresenta-se classificada como de maior risco, representado pelas classes “alto”, “muito alto” e “extremo”. Ao comparar o mapa final do risco de incêndio florestal para a área de estudo com o histórico de áreas queimadas, verificou-se que 94,83% dos registros de incêndios florestais estão alocados nas áreas de maior risco.Spatial modeling of forest fire risk for the Municipality of Inhambupe, Bahia State, BrazilSpatial modeling of forest fire risk has the aim to determine areas most susceptible to fire based on variables that represent facility of ignition and propagation. This work developed a forest fire risk map for the Municipality of Inhambupe, Bahia State, Brazil, by elaborating thematic maps of the following variables: road system, population density, land occupation and use, watershed network, slope and aspect. These were evaluated by the analytic hierarchy process and integrated with map algebra. Based on the developed model, 75.46% of the studied area was classified as “high”, “very high” and “extreme high” fire risk. When comparing the forest fire risk map with historical data of burned areas, 95% of the fires were in these areas.Index terms: Forest protection; Fire susceptibility; Risk map
Ecological succession is a complex processes involving changes in the structure of plant community and it is an important factor determining the structure of arboreal ants assemblages, but little is known about the effects of succession on ant assemblages in regions of Tropical Dry Forests (TDFs), such as the Brazilian Caatinga. The aim of this study was to investigate the effects of ecological succession on the richness and species composition of arboreal ants in fragments of Caatinga, testing the following hypothesis: i) the richness of arboreal ants increases along a gradient of forest succession, in response to tree richness and/or density; ii) species composition of arboreal ants differs among stages of forest succession due to differences in vegetation structure in theses stages. This study was conducted in 15 plots distributed in three areas with different stages of secondary succession (early, intermediate and late). Tree density and richness were used as surrogate of vegetation structure. Ants were sampled using the technique of beating the foliage and baited pitfall traps, where five trees were sampled per plot, totaling 75 individual trees sampled. We sampled 37 species of ants, distributed in 16 genera and five subfamilies. Ant richness differed among stages of succession and seasons, with higher number of species in the late succession and rainy period, also increasing with tree richness and density. Besides, there was a distinct composition of ant species among stages of succession and seasons. Results obtained in this study reinforce the importance of using ants as environmental bioindicators, since the sensitivity to environmental variations of this group enables us to differentiate early and late successional stages of forest succession in Caatinga environment.
ResumoEucalyptus é o gênero florestal plantado em maior quantidade no Brasil, sendo sua madeira utilizada, principalmente, para a produção de celulose. Incêndios florestais dentro de plantações dessas espécies acabam por danificar ou consumir a matéria-prima, gerando prejuízos de ordem econômica. O presente trabalho teve por objetivo caracterizar o material combustível superficial nos povoamentos de eucalipto pertencentes à empresa Copener Florestal Ltda., localizados no litoral norte da Bahia, e, por conseguinte, determinar o comportamento do fogo em diferentes cenários com base em simulações computacionais utilizando o BehavePlus Fire Modeling System. Para tal, foram realizadas 40 amostragens destrutivas de coleta de material combustível em 5 distintos povoamentos de 6 anos. A espessura do leito foi definida por meio de transectos linha, e a velocidade do vento, com base em dados da estação meteorológica Salgado. Demais dados foram obtidos através de consulta à literatura. Os povoamentos de eucalipto apresentaram em média 11,31 t/ha de material combustível, espessura do leito média de 5,94 cm e velocidade do vento média de 4,45 km/h. Com base nas simulações, foi definido que apenas no cenário de alto perigo é essencial a utilização de equipamentos de grande porte para combate ao fogo. Palavras-chave: Incêndios florestais; proteção florestal; silvicultura. AbstractCharacterization of the understory fuel load and fire behavior simulation in eucalyptus plantations in north coast of Bahia, Brazil. Currently, eucalyptus is the most planted forest genus in Brazil, being its wood used mainly for the production of cellulose. Forest fires in plantations of these species eventually damage or consume the raw material, generating economic losses. This work aims to characterize the surface fuel load in eucalypt plantation of the Copener Florestal Ltda. company, located on the northern coast of Bahia, and, therefore, determine the fire behavior in different scenarios based on computer simulations using the BehavePlus Fire Modeling System. In order to that, we conducted 40 destructive sampling in 05 different 06 years old stands. The fuel bed depth was determined through transect line methodology, and the wind speed was based on data from the Salgado weather station. Other data were obtained from the literature. The eucalyptus plantations had on average 11.31 t/ha fuel load, 5.94 cm of fuel bed depth average, and average wind speed of 4.45 km/h. Based on the simulations it was defined that only in the scenario of high risk it is essential to use large equipment for firefighting. In low and medium hazard scenarios fire can be extinguished by people using hand equipments.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.