1000 resultados para caatinga nativa melhorada
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Includes indexes.
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The genus Hemidactylus Oken, 1817 has cosmopolite distribution, with three species occurring in Brazil, two of them native, H. brasilianus and H. agrius, and one exotic, H. mabouia. Considering the studies about ecology of lizards conducted in the Ecological Station of the Seridó, from 2001 to 2011, this study aimed (1) to re-evaluate the occurrence of the species of Hemidactylus in this ESEC; (2) to analyze ecological and biological aspects of the H. agrius population; and (3) to investigate the current and potential distribution of the native species of the genus in northeastern Brazil, analyzing the suitability of ESEC to this taxon. For the first two objectives, a sampling area consisting of five transects of 200 x 20 m, was inspected in alternating daily shifts for three consecutive days, from August 2012 to August 2013. For the latter objective, occurrence points of H. agrius and H. brasilianus from literature and from the database of Herpetological Collections of the UFRN and the UNICAMP were consulted to build predictive maps via the Maximum Entropy algorithm (MaxEnt). In ESEC Seridó, 62 H. agrius individuals were collected (25 females, 18 males and 19 juveniles), and two neonates were obtained from a communal nest incubated in the laboratory. No record was made for the other two species of the genus. Hemidactylus agrius demonstrated to be a nocturnal species specialized in habitats with rocky outcrops; but this species is generalist regarding microhabitat use. In the population studied, females had an average body length greater than males, and showed higher frequencies of caudal autotomy. Regarding diet, H. agrius is a moderately generalist species that consumes arthropods, especially insect larvae, Isoptera and Araneae; and vertebrates, with a case of cannibalism registered in the population. With respect to seasonal differences, only the number of food items ingested differed between seasons. The diet was similar between sexes, but ontogenetic differences were recorded for the total volume and maximum length of the food items. Significant relationships were found between lizard body/head size measurements and the maximum length of prey consumed. Cases of polydactyly and tail bifurcation were recorded in the population, with frequencies of 1.6% and 3.1%, respectively. In relation xv to the occurrence points of the native species, 27 were identified, 14 for H. agrius and 13 for H. brasilianus. The first species presented restricted distribution, while the second showed a wide distribution. In both models generated, the ESEC Seridó area showed medium to high suitability. The results of this study confirm the absence of H. brasilianus and H. mabouia this ESEC, and reveal H. agrius as a dietary opportunist and cannibal species. Further, the results confirm the distribution patterns shown by native species of Hemidactylus, and point ESEC Seridó as an area of probable occurrence for the species of the genus, the establishing of H. brasilianus and H. mabouia are probably limited by biotic factors, a fact yet little understood
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Environmental degradation is a global problem that particularly affects areas subject to seasonal climatic variations, such as the brazilian semiarid region, namely the Caatinga Domain. Combined with other negative factors, such as natural resource misuse and disorderly land occupation, the consequences of Environmental Degradation have challenged science in the quest for addressing the resulting social and environmental problems. Accordingly, Environmental Perception methodology, by analyzing the concepts, attitudes and values, (especially those pertaining to environmental conservation) represent an important tool in studies that address the relationship between the environment and human actions. Sustainability Indicators are also relevant tools to assess the possible causes and consequences of environmental problems. Among several Sustainability Indicators available, the PressuresState-Impact-Response (PSIR) method is an analytical tool that permits the grouping of factors affecting sustainability as well as their consequences for nature and human health, and thus indicate mitigating actions for society and the public authorities. From this perspective, three areas of Caatinga were studied in Rio Grande do Norte state: Seridó Ecological Station (ESEC), Municipality of Serra Negra do Norte; Private Natural Reserve Stoessel de Brito (PNRSB), Municipality of Jucurutu; and part of the Serra de Santana, Municipality of Tenente Laurentino Cruz. The areas are both legally protected and unprotected and subject to diferent management protocols, though their share the common characteristic of human misuse of natural resources. In this scenario, this thesis´ main goal was to introduce the rural communities into the conservation process, using the results of Environmental Perception of such communities, combined with the analysis of the sustainability of municipalities through PSIR. Information on Environmental Perception was obtained from primary and secondary data from previous studies carried out in the ESEC Seridó and PRNP Stoessel de Brito. Additional data was obtained through direct observation and interview forms applied to rural communities in the Municipality of Tenente Laurentino Cruz. The results showed that respondents possessed a broad knowledge regarding environmental degradation, its causes and consequences for the caatinga biome. PEIR analysis showed that environmental degradation was smaller in countries with protected areas, as compared to those without. The population´s knowledge about environmental degradation and their acceptance of conservation units, as showed by Environmental Perception Analysis, coupled with the results of PEIR, suggest that those attitudes may foster actions aimed at reduction of environmental degradation in the Caatinga domain
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Dengue fever, currently the most important arbovirus, is transmitted by the bite of the Aedes aegypti mosquito. Given the absence of a prophylactic vaccine, the disease can only be controlled by combating the vector insect. However, increasing reports of resistance and environmental damage caused by insecticides have led to the urgent search for new safer alternatives. Twenty - um plant s eed extracts from the Caatinga were prepared , tested and characterized . Sodium phosphate ( 50 mM pH 8.0) was used as extractor. All extracts showed larvicidal and ovipositional deterrence activity . Extracts of D. grandiflora, E. contortisiliquum, A. cearenses , C. ferrea and C. retusa were able to attract females for posture when in low co ncentration . In the attractive concentrations, the CE of E. contortisiliquum and A. cearenses were able to kill 52% and 100% of the larvae respectively . The extracts of A. cearenses , P. viridiflora, E. velutina, M. urundeuva and S. brasiliensis were also pupicides, while extracts of P. viridiflora, E. velutina, E. contortisiliquum , A. cearenses, A. colubrina, D. grandiflora , B. cheilantha , S. spectabilis, C. pyramidalis, M. regnelli e G. americana displayed adulticidal activity. All extracts were toxic to C. dubia zooplankton . The EB of E. velutina and E. contortisiliquum did not affect the viability of fibroblasts . In all extracts were identified at least two potential insecticidal proteins such as enzyme inhibitors, lectins and chitin - binding proteins and components of secondary metabolism . Considering all bioassays , the extracts from A. cearenses, P. viridiflora, E. contortisiliquum , S. brasiliensis, E. velutina and M. urundeuva were considered the most promising . The E. contortisiliquum extracts was the only one who did not show pupicida activity, indicating that its mechanism of action larvicide and adulticidal is related only to the ingesti on of toxic compounds by insect , so it was selected to be fragmenting. As observed for the CE , th e protein fractions of E. contortisiliquum also showed larvicidal activity, highlighting that F2 showed higher larvicidal activity and lower en vironmental toxicity than the CE source. The reduction in the proteolytic activity of larvae fed with crude extra ct and fractions of E. contortisiliquum suggest ed that the trypsin inhibitors ( ITEc) would be resp onsible for larvicidal activity . However the increase in the purification of this inhibitor resulted in loss of larvicidal activity , but the absence of trypsin inhibitor reduced the effectiveness of the fractions , indicating that the ITEC contributes to the larvicidal activity of this extract. Not been observed larvicidal activity and adulticide in rich fraction vicilin, nor evidence of the contribution o f this molecule for the larvicidal activity of the extract. The results show the potential of seeds from plant extracts of Caatinga as a source of active molecules against insects A. aegypti at different stages of its development cycle, since they are comp osed of different active compounds, including protein nature, which act on different mechanisms should result in the death of insec
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The Caatinga and Atlantic Forest exhibit great species richness, which can attend requirements for various uses. Considering the current level of degradation of vegetation in Rio Grande do Norte, and the increasing use of exotic species, it is urgent to perform actions for the conservation of these biomes. From this perspective, using native plant species in the urban forestry becomes an instrument for the conservation and enhancement of local biodiversity. In this context, the general objective of this study is to gather and provide information about the ornamental native tree species in the state in order to promote and disseminate their use in urban areas. Specific aims of this work are: (1) evaluate and verify the demand and maintenance costs of native and exotic urban forestry, comparatively, with data obtained in the state (Cap. 1); (2) Provide a ornamental native tree species list in the state, including species already widespread use and suggesting new elements with ornamental potential (Cap. 2); and (3) produce a guide of native tree species as a means of disseminating the results obtained in a way accessible to the society. Analysis of maintenance of urban trees was performed at the UFRN's Central Campus, and the ornamental native tree species survey was carried out through literature survey combined with expeditions to forest fragments in the state. As a result, it was obvious that the maintenance of native vegetation resulted in lower costs and least demand for services highlighting the visible advantage in using a afforestation with regionalized floristic composition. The survey of ornamental native tree species led to the selection of 95 species belonging to 30 families, 17 species (17.35%) occurring exclusively in the Caatinga, 27 species (25.55%) in the Atlantic Forest and more than half (55.10%) occurring in both biomes, which provides a good selection available for the composition of urban forestry, both for cities located in the area of Atlantic Forest (81 spp.) or for those located in the Caatinga (71 spp.). From these results, a guide for the recognition and cultivation of native ornamental trees was prepared, consisting in the initial step in the enhancement of existing floristic potential value with the aim to assist in the development of a regionalized perspective of urban environmental management in the state
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The objective of the present thesis was to use the manipulation of oocytes enclosed in preantral follicles (MOEPF) as a tool for the female gametes rescue and optimization, from wild species of Caatinga biome. The thesis was divided into 4 experiments. At first experiment, it was performed the estimative and description of the agouti (Dasyprocta leporina) preantral follicles (PF) histologic and ultrastructural features, in which it was estimated 4419.8 ± 532.26 and 5397.52 ± 574.91 follicles for the right and left ovary, respectively, and the majority (86,63%) belonged to the primordial follicles category (P<0.05). Most of the population consists of morphologically normal follicles (70.78%), presenting a large and central nuclei and uniform cytoplasm. At ultrastructural evaluation it was verified the presence of a great number of round mitochondrias associated to lipid droplets. In the second experiment, it was performed the estimative and description of yellow-toothed cavies (Galea spixii) PF characteristics, also, the evaluation of the effect of solid surface vitrification (SSV) on the in situ PF morphology. The total of 416.0 ± 342.8 PF was estimated for the ovary pair and the presence of a large quantity of primary follicles (P<0.05) was evidenced. Most of the PF was morphologically normal (94.6%), in which the oocyte nuclei presented condensed granules of heterochromatin. Round or elongated shaped mitochondria constituted the most abundant organelles. In regard of the SSV, the protocol using the dimethylsulfoxide (DMSO) 3M possibility the preservation of 69.5% of morphologically normal PF, which was evidenced by the light and transmission electronic microscopy. At third experiment, the evaluation of the SSV procedure on the morphology and viability in situ PF form collared peccaries (Pecari tajacu) was performed. No differences were observed among treatments, in which the use of DMSO, ethylene glycol (EG) and dimethylformamide (DMF) as cryoprotectants, regardless its concentration, promoted the morphology preservation of much than 70% of PF. Concerning the PF viability, the DMSO and EG promoted the best preservation. The fourth experiment aimed to evaluate the effect of α MEM+ or TCM199 associated or not to 50 ng of FSHr on the morphology, activation and growth of collared peccaries PF, in vitro cultured (IVC) during 1 or 7 days and the effect on the extracellular matrix (ECM). After 7 days of IVC only the use of TCM199/FSH maintained the proportion of intact PF, similar to day 1(63.2%), however, no differences were observed among treatments (P>0.05). Also, an improvement of the proportion of intact growing PF was verified (P>0.05). By the Ag-NOR analysis it was observed that only the treatment using TCM199/FSH promoted the maintenance of cell proliferation similar to day 1 (P>0.05). The picrosirius red stain revealed that ECM remained intact in all treatments (P>0.05). Thus, as the general conclusion, the use of MOEPF in the refereed species allowed the knowledge of aspects related to its reproductive morphology and physiology, enabling the germplasm conservation, with the possibility of germplasm bank formation, as the elucidation of mechanisms related to the PF survive and in vitro development.
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The trophic ecology studies issues related to the diet of individuals within a community .The relation between the body size of the predator and the prey size, individual specialization and niche breadth are some of the issues that can be discussed by it .I collected the lizards using pitfall trap, glue and active collecting traps in a fragment of Caatinga. The most common species in this community were Tropidurus hispidus, T. semitaeniatus and Cnemidophorus ocellifer. The visits to the farm also relied on collecting invertebrates at each season to understand how the nutritional resources of lizards were presented in each one of them. I tried to answer some questions : 1) If there was a positive relation between body size of the predator and the size of prey of the community ; 2) If in different seasons the relation of body size of the predator and the maximum and/or minimum size of the prey would be positive ; 3) If species with different foraging strategies have positive relation on the size of the predatorprey relation; 4) If the seasonality would influence on the individual expertise of lizards community and more common species; 5) If the breadth of the niche would be influenced by seasonality ; 6) If more individuals with different morphology between them would present less similar diet. I found that there was indeed a positive relationship between size of prey and predator, but nonexistent related to the minimum size of prey; Among the seasons relative size of predators and prey was different for the maximum and minimum size, but was positively related only to the size of the maximum prey. And comparisons between different foraging strategies had the maximum and minimum line inclination greater than zero and different from each other; individual specialization was not influenced by seasonality and the niche breadth was wider in the dry season only to T. semitaeniatus. At last I didn't find a significant negative relationship between morphological dissimilarity and similarity of diet.
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The caatinga is considered the only exclusively Brazilian biome, with a total area of 735.000km². It is estimated that about 59% of this area has already been removed and only 2% are protected in conservations units. The region is characteristic by strong seasonality and heterogeneity in their environments. This paper sets generate information on morphological and population patterns Lanio pilatus in two areas of caatinga of Estação Ecológica do Seridó (ESEC – Seridó), Serra Negra do Norte - RN. Data collection was performed in six phases between July 2012 and December 2014, covering the end of the dry and rainy seasons in the region. The captures were performed with nets and individuals captured were marked with metal rings and measured (weight, wing length, tail, tarsus, culmen and tip of the bill to nostril). Through these measures, we observed that only males of open area range in weight during the dry and rainy season, youngs were significantly lower for all parameters measured, and males were larger than females in three characteristics (weight, wing length and tail) in open area and only one (wing length) in the closed area. The population parameters were generated from the mark-capture-recapture technique by program MARK, using the techniques of robust design and CJS. The survival probability of detection and population estimates varied with time. Only individuals of open area fluctuated in their estimates during the study. Overall, the environment was a great mediator of results which increases the need for more studies on the life history of the species in the region.
Influência das condições ambientais no verdor da vegetação da caatinga frente às mudanças climáticas
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The Caatinga biome, a semi-arid climate ecosystem found in northeast Brazil, presents low rainfall regime and strong seasonality. It has the most alarming climate change projections within the country, with air temperature rising and rainfall reduction with stronger trends than the global average predictions. Climate change can present detrimental results in this biome, reducing vegetation cover and changing its distribution, as well as altering all ecosystem functioning and finally influencing species diversity. In this context, the purpose of this study is to model the environmental conditions (rainfall and temperature) that influence the Caatinga biome productivity and to predict the consequences of environmental conditions in the vegetation dynamics under future climate change scenarios. Enhanced Vegetation Index (EVI) was used to estimate vegetation greenness (presence and density) in the area. Considering the strong spatial and temporal autocorrelation as well as the heterogeneity of the data, various GLS models were developed and compared to obtain the best model that would reflect rainfall and temperature influence on vegetation greenness. Applying new climate change scenarios in the model, environmental determinants modification, rainfall and temperature, negatively influenced vegetation greenness in the Caatinga biome. This model was used to create potential vegetation maps for current and future of Caatinga cover considering 20% decrease in precipitation and 1 °C increase in temperature until 2040, 35% decrease in precipitation and 2.5 °C increase in temperature in the period 2041-2070 and 50% decrease in precipitation and 4.5 °C increase in temperature in the period 2071-2100. The results suggest that the ecosystem functioning will be affected on the future scenario of climate change with a decrease of 5.9% of the vegetation greenness until 2040, 14.2% until 2070 and 24.3% by the end of the century. The Caatinga vegetation in lower altitude areas (most of the biome) will be more affected by climatic changes.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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O estudo dos efeitos que a diversidade de espécies pode causar nos processos ecossistêmicos tem crescido vertiginosamente nas últimas duas décadas. Diversos trabalhos experimentais realizados no mundo todo têm demonstrado que uma maior diversidade de plantas contribui para o aumento da produtividade de ecossistemas terrestres. Além disso, esse efeito pode influenciar processos em diversos níveis tróficos, contribuindo assim para a estabilidade dos processos ecossistêmicos a longo prazo. Paralelamente com os estudos do efeito da diversidade, muita atenção tem sido dada para desvendar o papel das características funcionais das espécies no funcionamento dos ecossistemas. Isto porque as características funcionais das espécies têm se mostrado importantes "peças" no entendimento dos efeitos que espécies individuais podem exercer nos ecossistemas e suas respostas ao ambiente. Nesta tese de doutorado eu explorei algumas lacunas de conhecimento dentro dessa área em crescente desenvolvimento conhecida na literatura ecológica como "biodiversidade e funcionamento dos ecossistemas". No primeiro capítulo, eu busquei evidências para mecanismos que podem explicar a relação positiva entre diversidade e funcionamento com foco em cinco mecanismos relacionados às interações entre plantas, tendo como parâmetro de funcionamento a produtividade primária. No segundo capítulo, eu utilizei técnicas para a estimativa de padrões de diversidade em escalas biogeográficas e bases de dados de satélites com longa duração para desvendar se a biodiversidade em escalas macroecológicas promove a estabilidade da produtividade dos ambientes terrestres no semiárido brasileiro. Por fim, o objetivo do terceiro capítulo foi entender como a perda da cobertura vegetal originária do uso da terra por comunidades tradicionais no semiárido brasileiro influenciaria os processos de interações entre plantas e o papel das características funcionais das espécies nessas interações. Acredito que a contribuição individual de cada capítulo preenche lacunas de conhecimento importantes dessa área da Ecologia que ainda se encontra em expansão.
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While the carnivores are considered regulators and structuring of natural communities are also extremely threatened by human activities. Endangered little-spotted-cat (Leopardus tigrinus) is one of the lesser known species from the Neotropical cats. In this work we investigate the occupancy and the activity pattern of L. tigrinus in Caatinga of Rio Grande do Norte testing: 1) how environmental and anthropogenic factors influence their occupation and 2) how biotic and abiotic factors influence their activity pattern. For this we raised occurrence data of species in 10 priority areas for conservation. We built hierarchical models of occupancy based on maximum likelihood to represent biological hypotheses which were ranked using the Akaike Information Criterion (AIC). According to the results the feline occupancy is more likely away from rural settlements and in areas with a higher proportion of woody vegetation. The opportunistic killing of L. tigrinus and in retaliation for poultry predation close to residential areas can explain this result; as well as more complex vegetation structure can better serve as refuge and ensure more food. Analyzing the records of the species through circular statistics we conclude that the activity pattern is mostly nocturnal, although considerable crepuscular and a small diurnal activity. L. tigrinus activity was directly affected by the availability of small terrestrial mammals, which are essentially nocturnal. In addition, the temperatures recorded in the environment directly and indirectly affect the activity of the little-spotted-cat, as also influence the activity of their potential prey. Generally, the cats were more active when possible prey were active, and this happened at night when lower temperatures are recorded. Moreover, the different lunar phases did not affect the activity pattern. The results improve the understanding of an endangered feline inhabiting the Caatinga biome, and thus can help develop conservation and management strategies, as well as in planning future research in this semi-arid ecosystem.
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Despite the importance of the study of roots, little is known about the negative effects of soil compaction in the development of the Caatinga forest species. In this sense, the objective was to evaluate the initial growth of Mimosa caesalpiniifolia, Tabebuia caraiba and Erythina velutina in soil under varying levels of compression. The experiment was conducted in a greenhouse located at the Academic Unit Specialized in Agricultural Sciences, UFRN. To perform the experiment, was used Oxisoil of sandy loam texture, from forest trial Area Agricultural School of Jundiaí (EAJ) of the municipality of Macaíba-RN, in an experimental unit consisting of three overlapping PVC rings, 10 cm in diameter and 25 cm in height, with a central ring which has undergone compression. The experimental design was a randomized block with six replications, being tested four levels of soil compaction (1.35; 1.45; 1.60 and 1.80 kg.dm-³), evaluating the following variables: diameter, height, number of leaves, dry weight of shoot and root system in each layer of the vessels. Overall, the species M. caesalpiniifolia, T. caraiba and E. velutina had initial growth favored by treatment consists of uncompressed soil. The M. caesalpiniifolia and T. caraiba species proved relatively resistant to compaction of the soil does not undergo any significant reduction in root growth density equal to or less than 1.60 kg.dm-³, whereas E. velutina proved susceptible effects of soil compaction, with significant changes in root growth under soil densities equal to or greater than 1.45 kg.dm-³. Increased soil compaction caused the impediment to the expansion of taproot inside the experimental units, promoting the accumulation of roots in the upper layers of the soil for the studied species. The subsoil physical impediment changed the initial aerial growth of M. caesalpiniifolia and E. velutina, but did not influence the growth of air T. caraiba seedlings the tested compression levels.
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Cervídeo Mazama gouazoubira é a espécie de veado que possui maior distribuição dentre as espécies sul americanas. Aspectos da vegetação, predação, competição, caça e perda de habitat são fatores importantes para compreender a distribuição espacial de herbívoros na paisagem. Dessa forma, considerando a falta de estudos de mamíferos de médio e grande porte na Caatinga, objetivamos compreender quais os fatores ambientais e antrópicos que influenciam a ocupação do veado-catingueiro (M. gouazoubira) na região semiárida do estado do Rio Grande do Norte, Brasil. O estudo foi realizado em 10 áreas amostrais e utilizamos armadilhas fotográficas para amostragem e modelos de ocupação foram construídos representando nossas hipóteses biológicas. Os modelos foram ranqueados através dos valores obtidos do AIC. As variáveis cobertura vegetal de caatinga e densidade da vegetação mostraram maior efeito, já a caatinga arbórea mostrou um efeito menor, sugerindo que a espécie é altamente dependente da vegetação para ocorrer, possuindo menor dependência de caatinga arbórea. Esperamos que nossos resultados possam ser utilizados como suporte para planos de manejo e criação de novas unidades de conservação no estado.
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El Perú presentas cuenta con pisos altitudinales idóneos para el cultivo de más de 3000 variedades de papas nativas, siendo este cultivo la principal fuente de ingresos y alimentación de pequeños productores. Este tubérculo posee una riqueza inigualable en nutricional, ambiental, genética y cultural, que en los últimos años presenta una creciente demanda, reflejado en el incremento del consumo per cápita de papa en el Perú, alcanzando los 85 kg per cápita en la actualidad. Este aumento se debió en parte al mejorar el nivel socioeconómico de la población y eventos que promueven el consumo de papas nativas. En el 2000, el proyecto INCOPA teniendo como base la ley 27360, promovió la creación y formación de asociaciones en las zonas productoras de papa nativa en la sierra. Esta intervención de dicho proyecto genero innovaciones organizacionales y tecnológicas en el sector de la papa nativa. Un caso exitoso fue el de la Asociación Agropecuaria Los Andes de Kishuará, logro implementar innovaciones organizacionales y tecnológicas, que les llevo a mejorar su productividad con resultados económicos positivos e incursionar a supermercados con productos, repercutiendo en mejoras en la calidad de vida de los productores de la asociación, creando así valor social. De aquí parte el objetivo de esta investigación, la cual es identificar las innovaciones tecnológicas y organizacionales, en la Asociación agropecuaria Los Andes de Kishuará para comprender el rápido posicionamiento de su producto en el canal supermercado. La metodología utilizada fue un estudio de caso, que describirá a la asociación y sus innovaciones en el ambiente organizacional y tecnológico. Los resultados obtenidos definen a la Asociación agropecuaria Los Andes de Kishuará es producto de la acción colectiva que dio como resultado la intervención del proyecto INCOPA. Pues esta asociación se ha desarrolla eficientemente, adaptándose a las distintas perturbación y oportunidades del mercado; estratégicamente con una innovación en su diseño organizacional que permitió implementar innovaciones tecnológicas, obteniendo un proceso de producción eficiente y de calidad. Además, de la alianza estratégica que tuvo la asociación con CAPAC PERÚ, con objeto de ampliar horizonte comercial, permitió incursionar y posicionarse en los supermercados de Lima, al brindar papas nativas que el cliente requería logrando satisfacer las exigencias del consumidor. Sin embargo, esta asociación aun cuenta con problemas que deben superarse a corto plazo.