scholarly journals Spatial Distribution of Tibraca limbativentris (Heteroptera: Pentatomidae) in Babassou Palms

2021 ◽  
Vol 9 (2) ◽  
pp. 537
Author(s):  
Elizabeth Araújo Costa ◽  
Raimunda Nonata Santos Lemos ◽  
Keneson Klay Gonçalves Machado ◽  
Gislane Da Silva Lopes ◽  
Janaina Marques Mondego ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Solar Radiation ◽  
Abiotic Factors ◽  
Gaussian Model ◽  
Spatial Arrangement ◽  
Northeastern Brazil ◽  
Palm Tree ◽  
Monthly Basis ◽  
Palm Trees ◽  
Significant Difference

The babassou plant (Attalea speciosa Mart. Ex. Spreng, Arecaceae) is an important palm tree in the state of Maranhão, northeastern Brazil. This plant is the main arboreal component in extensive geographical areas including agricultural areas. However, limited research studies exist on its role as an alternative pest host in this region. This study investigated the occurrence of Tibraca limbativentris Stal (1860) in young babassou palm trees, the effect of abiotic factors (temperature, solar radiation and rainfall) on the number of T. limbativentris adults and postures, and this insect’s spatial arrangement during the rice crop off-season. The research team inspected young babassou plants on a monthly basis in 2012 and 2013 to collect and quantify postures and adults. They collected a total of 1418 live adults, 13 dead and ten postures of T. limbativentris. There was a significant difference between the first and the other collections of live adults carried out in 2012 and 2013. Abiotic factors including rainfall, temperature and solar radiation, had no influence on the number of adults (alive and dead) and postures. The semivariogram adjusted to the Gaussian model showed that in 2013, the spatial distribution of living adults, that had an aggregate pattern, was highly dependent on the season. However, in 2012 there was a pure nugget effect. These results imply that young babassou plants are alternative T. limbativentris hosts.

Large-scale mapping of the catenas vegetation in Subarctic tundra

1995 ◽  
pp. 3-21
Author(s):  
S. S. Kholod
Keyword(s):  
Spatial Distribution ◽  
Vegetation Cover ◽  
Large Scale ◽  
Block Diagram ◽  
Abiotic Factors ◽  
Ecological Factors ◽  
Spatial Arrangement ◽  
Geological Time ◽  
Ecological Barriers ◽  
Functional Zones

One of the most difficult tasks in large-scale vegetation mapping is the clarification of mechanisms of the internal integration of vegetation cover territorial units. Traditional way of searching such mechanisms is the study of ecological factors controlling the space heterogeneity of vegetation cover. In essence, this is autecological analysis of vegetation. We propose another way of searching the mechanisms of territorial integration of vegetation. It is connected with intracoenotic interrelation, in particular, with the changing role of edificator synusium in a community along the altitudinal gradient. This way of searching is illustrated in the model-plot in subarctic tundra of Central Chukotka. Our further suggestion concerns the way of depicting these mechanisms on large-scale vegetation map. As a model object we chose the catena, that is the landscape formation including all geomorphjc positions of a slope, joint by the process of moving the material down the slope. The process of peneplanation of a mountain system for a long geological time favours to the levelling the lower (accumulative) parts of slopes. The colonization of these parts of the slope by the vegetation variants, corresponding to the lowest part of catena is the result of peneplanation. Vegetation of this part of catena makes a certain biogeocoenotic work which is the levelling of the small infralandscape limits and of the boundaries in vegetation cover. This process we name as the continualization on catena. In this process the variants of vegetation in the lower part of catena are being broken into separate synusiums. This is the process of decumbation of layers described by V. B. Sochava. Up to the slope the edificator power of the shrub synusiums sharply decreases. Moss and herb synusium have "to seek" the habitats similar to those under the shrub canopy. The competition between the synusium arises resulting in arrangement of a certain spatial assemblage of vegetation cover elements. In such assemblage the position of each element is determined by both biotic (interrelation with other coenotic elements) and abiotic (presence of appropriate habitats) factors. Taking into account the biogeocoenotic character of the process of continualization on catena we name such spatial assemblage an exolutionary-biogeocoenotic series. The space within each evolutionary-biogeocoenotic series is divided by ecological barriers into some functional zones. In each of the such zones the struggle between synusiums has its individual expression and direction. In the start zone of catena (extensive pediment) the interrelations of synusiums and layers control the mutual spatial arrangement of these elements at the largest extent. Here, as a rule, there predominate edificator synusiums of low and dwarfshrubs. In the first order limit zone (the bend of pediment to the above part of the slope) one-species herb and moss synusiums, oftenly substituting each other in similar habitats, get prevalence. In the zone of active colonization of slope (denudation slope) the coenotic factor has the least role in the spatial distribution of the vegetation cover elements. In particular, phytocoenotic interactions take place only within separate microcoenoses of herbs, mosses and lichens. In the zone of the attenuation of continualization process (the upper most parts of slope, crests) phytocoenotic interactions are almost absent and the spatial distribution of vegetation cover elements depends exclusively on the abiotic factors. The principal scheme of the distribution of vegetation cover elements and the disposition of functional zones on catena are shown on block-diagram (fig. 1).

scholarly journals The palm tree Copernicia cerifera (carnaúba) as an ecotope of Rhodnius nasutus in rural areas of the State of Piauí Northeastern Brazil

1986 ◽  
Vol 19 (4) ◽  
pp. 243-245 ◽  
Author(s):  
Artur da S. Pinto ◽  
Dalva N. da C. Bento
Keyword(s):  
Trypanosoma Cruzi ◽  
Rural Areas ◽  
The State ◽  
Northeastern Brazil ◽  
Palm Tree ◽  
Palm Trees ◽  
Triatomine Species

The C. cerifera palm tree (carnaúba) is widely distributed in the Northeastem Brazil, including the State of Piauí. This investigation revealed that R. nasutus is the ortly triatomine species captured on that palm tree, in five different localities. 78% of palm trees were infested with triatomines, and 4.0% were infected with flagellates morphologically and biologically indistinguishable from Trypanosoma cruzi. Birds, rodents and marsupials were found as major blood meai sources for R. nasutus.

scholarly journals Epidemiologic studies of chagas' disease in the urban zone of Teresina. State of Piauí, northeastern Brazil

1984 ◽  
Vol 17 (4) ◽  
pp. 199-203 ◽  
Author(s):  
Dalva N. da C. Bento ◽  
Ana Z. C. L Branco ◽  
Marise R. Freitas ◽  
Artur da S. Pinto
Keyword(s):  
Chagas Disease ◽  
Epidemiologic Studies ◽  
Northeastern Brazil ◽  
Palm Tree ◽  
Natural Focus ◽  
Predominant Species ◽  
Palm Trees ◽  
Urban Zone ◽  
Triatomine Species ◽  
Infection Index

The triatomine species Rhodnius nasutus and Triatoma pseudomaculata were captured on palm trees Orbignya martiana "babaçu ", in the urban zone of Teresina. This kind of palm tree is largely distributed in Piauí State. The predominant species was R. nasutus; the young in stars predominated. The infestation index of palm trees and the infection index of triatomines by flagellates were 96.0 ana 29.1%, respectively. Marsupiais, bats and a rodent were captured in palm trees. The flagellates found in both triatomines ana marsupiais were morphologically and biologically indistinguishable from Trypanosoma cruzi. Forty seven percent (481/1,025) of triatomines were found concentrated in six palm trees where marsupiais circulated. Of the total of 1,025 triatomines 230 (22%) were infected by flagellates and 53.0% (123/230) of these infected triatomines were present in the same six palm trees. No evidence of triatomine domiciliation or human transmission was observed in the houses in the vicinity of palm trees. The results suggest that marsupiais play an important role in the life-cycle of T. cruzi in this region. The natural focus of Chagas' disease, demonstrated in the present study could represent a potential epidemiological threat.

scholarly journals Carnaúba (Copernicia prunifera (Miller) H. E. Moore uma nova hospedeira de Raoiella indica Hirst (Acari: Tenuipalpidae)

2021 ◽  
Vol 3 ◽  
pp. ec03045
Author(s):  
Eduardo P. Sousa Neto ◽  
Izabel V. Souza ◽  
Elio C. Guzzo ◽  
José Wagner S. Melo
Keyword(s):  
Host Range ◽  
Potential Risk ◽  
Neotropical Region ◽  
Northeastern Brazil ◽  
High Population ◽  
Palm Tree ◽  
Suitable Host ◽  
Red Palm Mite ◽  
Palm Trees ◽  
Raoiella Indica

The red palm mite, Raoiella indica Hirst, 1924 (Tenuipalpidae), has been spreading rapidly and expanding its host range in the Neotropical region. Most of the hosts are palm trees (Arecaceae). In the present work, high population levels of R. indica are reported on “carnauba” [Copernicia prunifera (Miller) H. E. Moore, Arecaceae] in the states of Alagoas and Ceará, northeastern Brazil. This is the first report of R. indica causing damage and injuries on this palm tree native to Brazil in field. Our results allow us to conclude that carnauba is a suitable host for R. indica, with potential risk to its cultivation and exploitation.

scholarly journals Sleeping sites of woolly mouse opossum Micoureus demerarae (Thomas) (Didelphimorphia, Didelphidae) in the Atlantic Forest of south-eastern Brazil

2005 ◽  
Vol 22 (4) ◽  
pp. 839-843 ◽  
Author(s):  
Edsel A. Moraes Junior ◽  
Adriano G. Chiarello
Keyword(s):  
Tree Species ◽  
Radio Telemetry ◽  
Palm Tree ◽  
Average Height ◽  
Palm Trees ◽  
Eastern Brazil ◽  
Significant Difference ◽  
Tree Holes ◽  
Sleeping Sites ◽  
Chi2 Test

Micoureus demerarae (Thomas, 1905) is a medium-sized marsupial, around 130 g, with a nocturnal habit and insectivorous-omnivorous diet. From August 2001 to July 2002, seven individuals, three males and four females, were monitored with radio-telemetry in Reserva Biológica União, state of Rio de Janeiro, Brazil, aiming to investigate and describe the sleeping sites used by this marsupial. Fifty eight sleeping sites were located, most of which (70,7%) in palm trees Astrocaryum aculeatissimum (Schott) Burret, and the remaining in other tree species (29,3%), a significant difference (chi2 test; p < 0.005). The preference for this palm tree was not different between sexes (chi2 test; p = 0.920). It was possible to locate the exact place where the animal was hiding in 31 sleeping sites (53.4% of total) in palm trees the animals were always in the junction point of petioles and tree trunks, at an average height of 4.66 ± 1.36 m, while in the remaining tree species, seven individuals were in liana tangles and two in tree holes, at an average height of 10.67 ± 2.75 m. This height difference was significant (Mann Whitney test; p < 0.001). Results indicate that palm trees are important resources for M. demerarae. The observed preference for A. aculeatissimum is probably due to higher protection against predators made by the numerous spines of this palm tree species.

scholarly journals Impacts of Climate Change Interacting Abiotic Factors on Growth, aflD and aflR Gene Expression and Aflatoxin B1 Production by Aspergillus flavus Strains In Vitro and on Pistachio Nuts

Toxins ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 385
Author(s):  
Alaa Baazeem ◽  
Alicia Rodriguez ◽  
Angel Medina ◽  
Naresh Magan
Keyword(s):  
Climate Change ◽  
Gene Expression ◽  
Water Stress ◽  
Aspergillus Flavus ◽  
Aflatoxin B1 ◽  
Abiotic Factors ◽  
Pistachio Nuts ◽  
Significant Difference ◽  
Spoilage Fungi

Pistachio nuts are an important economic tree nut crop which is used directly or processed for many food-related activities. They can become colonized by mycotoxigenic spoilage fungi, especially Aspergillus flavus, mainly resulting in contamination with aflatoxins (AFs), especially aflatoxin B1 (AFB1). The prevailing climate in which these crops are grown changes as temperature and atmospheric CO2 levels increase, and episodes of extreme wet/dry cycles occur due to human industrial activity. The objectives of this study were to evaluate the effect of interacting Climate Change (CC)-related abiotic factors of temperature (35 vs. 37 °C), CO2 (400 vs. 1000 ppm), and water stress (0.98–0.93 water activity, aw) on (a) growth (b) aflD and aflR biosynthetic gene expression and (c) AFB1 production by two strains A. flavus (AB3, AB10) in vitro on milled pistachio-based media and when colonizing layers of shelled raw pistachio nuts. The A. flavus strains were resilient in terms of growth on pistachio-based media and the colonisation of pistachio nuts with no significant difference when exposed to the interacting three-way climate-related abiotic factors. However, in vitro studies showed that AFB1 production was significantly stimulated (p < 0.05), especially when exposed to 1000 ppm CO2 at 0.98–0.95 aw and 35 °C, and sometimes in the 37 °C treatment group at 0.98 aw. The relative expression of the structural aflD gene involved in AFB1 biosynthesis was decreased or only slightly increased, relative to the control conditions at elevated CO, regardless of the aw level examined. For the regulatory aflR gene expression, there was a significant (p < 0.05) increase in 1000 ppm CO2 and 37 °C for both strains, especially at 0.95 aw. The in situ colonization of pistachio nuts resulted in a significant (p < 0.05) stimulation of AFB1 production at 35 °C and 1000 ppm CO2 for both strains, especially at 0.98 aw. At 37 °C, AFB1 production was either decreased, in strain AB3, or remained similar, as in strain AB10, when exposed to 1000 ppm CO2. This suggests that CC factors may have a differential effect, depending on the interacting conditions of temperature, exposure to CO2 and the level of water stress on AFB1 production.

scholarly journals Spatial distribution and survival rate of waterfrog tadpoles in relation to biotic and abiotic factors: a field experiment

2001 ◽  
Vol 22 (1) ◽  
pp. 21-32 ◽  
Author(s):  
Sylvie Thurnheer ◽  
Heinz-Ulrich Reyer
Keyword(s):  
Spatial Distribution ◽  
Community Dynamics ◽  
Abiotic Factors ◽  
Rana Esculenta ◽  
Natural Conditions ◽  
Major Purpose ◽  
Biotic And Abiotic Factors ◽  
Lab Experiments ◽  
Shallow Zone ◽  
Population And Community Dynamics

AbstractPredictions about population and community dynamics are usually based on lab experiments. Because the results are difficult to transfer to natural conditions, the major purpose of this study was to test the effects of biotic and abiotic factors on tadpole populations in a natural environment. We stocked six ponds, created the previous year, with known numbers of Rana esculenta and R. lessonae tadpoles and followed their development over several months. When compared among ponds, tadpole density correlated positively with the nitrate:phosphate ratio. This suggests that water chemistry may have affected survival, either directly or indirectly via productivity. Within ponds, both species showed a clear preference for the shallow zone. This behavior probably reflects a preference for warm water close to the surface, rather than avoidance of predators, because relative densities of odonates also increased from deep to shallow zones. This study is one of few that not only considers the distribution of the anuran tadpoles but the distribution of their predators as well.

Temporal variation in the weight-size relationship of the mangrove crab Ucides cordatus L. (Decapoda: Ucididae) in relation to its life cycle phases

2014 ◽  
Vol 64 (4) ◽  
pp. 333-342 ◽  
Author(s):  
Marcos de Miranda Leão Leite ◽  
Cynthia Yuri Ogawa ◽  
Carla Ferreira Rezende ◽  
José Roberto Feitosa Silva
Keyword(s):  
Life Cycle ◽  
Condition Factor ◽  
River Estuary ◽  
Total Weight ◽  
Northeastern Brazil ◽  
Annual Life Cycle ◽  
Ucides Cordatus ◽  
Mangrove Crab ◽  
Significant Difference ◽  
The Relationship

The relationship between weight and size of individuals can be used to evaluate the status of a population, which is particularly useful for natural populations that are being exploited. Ucides cordatus occurs on the Atlantic coast of the American continent, from Florida (USA) to Santa Catarina (Brazil). This species is economically very important, most of all in the Northeastern area of Brazil, as well as in the Dominican Republic and Suriname. The objective of this study was to analyze life phases (‘fattening’, ‘matumba’, ‘milk-crab’, ‘maturation’ and ‘walking’) by use of the weight-length relationships, as well as temporal variations in this condition factor for each sex of U. cordatus. For this purpose, individuals were sampled monthly for twenty-four months at the Jaguaribe River estuary, Ceará State, Northeastern Brazil. The relationship between total weight and cephalothorax width was established using regression analysis, adjusted by a power equation. The dynamics of the condition factor were analyzed for each sex using the variation of its averages related to annual life cycle; this was done for each of the previously-mentioned phases. The relationship between total weight and cephalothorax width showed an isometric growth in males and negative allometric growth in females suggesting that, for the same reference size, males are heavier than females. When considering the average of the female condition factors, these were greater than those for males during the annual life cycle, except during the ‘maturation’ phase, which is the phase with a higher demand of energetic reserves for males. Annual variation of the condition factor in females presented no significant difference.

Effect of Savanna windrow wood burning on the spatial variability of soil properties

2021 ◽  
Vol 51 ◽  
Author(s):  
Diogo Neia Eberhardt ◽  
Robélio Leandro Marchão ◽  
Pedro Rodolfo Siqueira Vendrame ◽  
Marc Corbeels ◽  
Osvaldo Guedes Filho ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Spatial Variability ◽  
Spatial Dependence ◽  
Chemical Properties ◽  
Spatial Arrangement ◽  
Nugget Effect ◽  
Tropical Savannas ◽  
Geostatistical Methods ◽  
Exchangeable Ca ◽  
Spherical Models

ABSTRACT Tropical Savannas cover an area of approximately 1.9 billion hectares around the word and are subject to regular fires every 1 to 4 years. This study aimed to evaluate the influence of burning windrow wood from Cerrado (Brazilian Savanna) deforestation on the spatial variability of soil chemical properties, in the field. The data were analysed by using geostatistical methods. The semivariograms for pH(H2O), pH(CaCl2), Ca, Mg and K were calculated according to spherical models, whereas the phosphorus showed a nugget effect. The cross semi-variograms showed correlations between pH(H2O) and pH(CaCl2) with other variables with spatial dependence (exchangeable Ca and Mg and available K). The spatial variability maps for the pH(H2O), pH(CaCl2), Ca, Mg and K concentrations also showed similar patterns of spatial variability, indicating that burning the vegetation after deforestation caused a well-defined spatial arrangement. Even after 20 years of use with agriculture, the spatial distribution of pH(H2O), pH(CaCl2), Ca, Mg and available K was affected by the wood windrow burning that took place during the initial deforestation.

scholarly journals Temporal variation of the phytoplankton community at short sampling intervals in the Mundaú reservoir, Northeastern Brazil

2008 ◽  
Vol 22 (4) ◽  
pp. 970-982 ◽  
Author(s):  
Ênio Wocyli Dantas ◽  
Ariadne do Nascimento Moura ◽  
Maria do Carmo Bittencourt-Oliveira ◽  
João Dias de Toledo Arruda Neto ◽  
Airlton de Deus C. Cavalcanti
Keyword(s):  
Phytoplankton Community ◽  
Abiotic Factors ◽  
Distribution Patterns ◽  
Northeastern Brazil ◽  
Cylindrospermopsis Raciborskii ◽  
Algae Biomass ◽  
Dissolved Phosphorus ◽  
Sampling Intervals ◽  
Abiotic Variables ◽  
Dry And Rainy Seasons

The aim of this study was to determine how abiotic factors drive the phytoplankton community in a water supply reservoir within short sampling intervals. Samples were collected at the subsurface (0.1 m) and bottom of limnetic (8 m) and littoral (2 m) zones in both the dry and rainy seasons. The following abiotic variables were analyzed: water temperature, dissolved oxygen, electrical conductivity, total dissolved solids, turbidity, pH, total nitrogen, nitrite, nitrate, total phosphorus, total dissolved phosphorus and orthophosphate. Phytoplankton biomass was determined from biovolume values. The role abiotic variables play in the dynamics of phytoplankton species was determined by means of Canonical Correspondence Analysis. Algae biomass ranged from 1.17×10(4) to 9.21×10(4) µg.L-1; cyanobacteria had biomass values ranging from 1.07×10(4) to 8.21×10(4) µg.L-1. High availability of phosphorous, nitrogen limitation, alkaline pH and thermal stability all favored cyanobacteria blooms, particularly during the dry season. Temperature, pH, total phosphorous and turbidity were key factors in characterizing the phytoplankton community between sampling times and stations. Of the species studied, Cylindrospermopsis raciborskii populations were dominant in the phytoplankton in both the dry and rainy seasons. We conclude that the phytoplankton was strongly influenced by abiotic variables, particularly in relation to seasonal distribution patterns.

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