http://repositorio.ufc.br/handle/riufc/330 2026-04-06T03:32:37Z http://repositorio.ufc.br/handle/riufc/84684 Título: Influência da restauração ecológica para sequestro de carbono em áreas tropicais semi-áridas submetidas a processos de desertificação Autor(es): Moreno, Juan Guillermo Cadena Abstract: The northeast of Brazil is facing desertification due to its semi-arid climate. This region is known for being one of the most populated in the world and for having a high poverty rate.This population depends on natural resources for their daily activities, and the misuse of resources such as cattle farming and deforestation of the caatinga is a growing problem in the semi-arid region. The aim of this study was therefore to identify the potential for restoring the caatinga biome through carbon and biomass stocks. In this work, three areas were analyzed (A- Degraded Area, B - Restoration Area, C - Test Area) in the municipality of Jaguaribe - CE,comparing physical and chemical soil attributes (indicators of fertility and nutrient availability, microbial activity - RBS) and calculating plant biomass based on stem diameter at ground level.The results indicate that the restoration area significantly improved its physical and chemical soil attributes in a way that did not differ statistically from the control area, which corroborates that ecological restoration is a nature-based solution to contribute to climate change mitigation and provide ecosystem services, such as carbon sequestration and biomass generation,beneficial to all species, including humans. The results indicate that the restoration area significantly improved its physical and chemical soil attributes in a way that did not differ statistically from the control area. In addition, the carbon stocks in the evaluated areas A = 9.10Mg ha-1, B = 15.16 Mg ha-1and C = 17.80 Mg ha-1increased considerably, which enabled revegetation and, consequently, biomass production B = 36.2 t ha-1and C = 43.8 t ha-1. Area A has no vegetation, which is why the biomass stock was not estimated. This corroborates that ecological restoration is a nature-based solution to help mitigate climate change and provide ecosystem services, such as carbon sequestration and biomass generation, which are beneficial to all species, including humans. Tipo: Dissertação 2024-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/84430 Título: Relações clima-crescimento de uma espécie nativa e uma invasora ao longo de um gradiente de aridez: uma análise dendrocronológica buscando compreender o sucesso de invasão Autor(es): Nascimento, Sandro Ferreira do Abstract: The establishment of invasive species results in a reduction in native biodiversity. The invasiveness characteristics of the species and of the receptor ecosystems confer competitive advantages for invasive success in new introduction environments. The highly competitive capacity of invasive exotic species is attributed to their faster and greater growth (plasticity) compared to native species. However, the methodologies used may distort the interpretation that invasive species are superior competitors to native species, since measuring biomass at the end of the experiment does not consider how resource dynamics may affect species growth. Therefore, this study aimed to investigate the influences of climatic conditions on the growth performance of an invasive and a native species along an aridity gradient in the semi-arid domain of the Caatinga. To this end, we analyzed the growth rings of the invasive Cryptostegia madagascariensis and the native Cobretum leprosum, which are co-occurring species in the coastal region of the state of Ceará and have similar growth patterns. Subsequently, we analyzed the effects of local and regional climatic factors on the growth of both species. Both species showed annual growth rings. The populations had a short life cycle within the invaded community (ages ≤ 20 years). There are no differences between the growth of invasive and native species. However, the growth of species responded negatively to climatic factors. The native species is affected by rising temperatures along the gradient. El Niño negatively affects the growth of native species with greater intensity in all areas studied; for invasive species, its effects are felt only in the driest areas. Through the annual growth rings of the species, we found that local environmental conditions do not greatly influence the growth of the invasive species, but reduce the growth of the native species with increasing temperatures, highlighting the plasticity of the invasive taxon. Tipo: Dissertação 2025-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/83007 Título: Osmóforos de Guazuma ulmifolia Lam. (Malvaceae): estrutura, funcionalidade e interações com visitantes florais Autor(es): Portela, Juliane da Silva Abstract: Many interactions between plants and pollinators are mediated by floral Volatile Organic Compounds (VOCs). Those compounds may be produced by specialized glands called osmophores, they play an important role in the attraction of pollinators. However, little attention has been paid to the functionality of the osmophores and its relation to the temporal variation of the floral VOCs secreted by them. To understand how the variation of the floral morphology and the release of scents by the osmophores affect the abundance, composition and behavior of floral visitor insects, this study used the flowers of Guazuma ulmifolia Lam. (Malvaceae) as a model. To evaluate the variation of morphology and release of floral scents, observations of changes in floral morphology, anatomic and histochemical analysis and gas chromatography were made. Data of abundance, composition and floral visitors’ behavior were collected, and insects were captured, measured and identified. The results show that the biggest release of compounds related to the attractions of insects happens on the second day of anthesis, which also corresponds to the day with the highest frequency and species richness. The male and female chambers show a distinct composition of visitors in relation to the body size. The results indicate that the scent acts as an important floral trait and the size of the access to the chamber acts as a limiting factor to the visitation. The results of behavior, abundance and acessibility of floral chambers has shown that small insects (Diptera, Coleoptera and Chalcidoidea wasps) are the pollinators of G. ulmifolia, therefore, it can be included in the SDI pollination system. Tipo: Dissertação 2022-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/82673 Título: Carcaças de peixes em rios intermitentes: fontes ou drenos de fósforo? Autor(es): Cunha, Sérgio Lucas da Rocha Abstract: Animals are directly and indirectly important in nutrient cycling. Fish represents steady poolsof nutrients in aquatic ecosystem recognized as nutrient sinks, accumulating over time morenutrients than is recycled by releasing. Nevertheless, considering fish as nutrient sink orsource depends on pool size, emigration and immigration, spatial and temporal biomasschanges, and fate of post mortem nutrients. Annual cease of flow in Intermittent rivers canpromotes fish kills that potentially causes sources of nutrients. The goal of this study is toinvestigate if fish carcasses represents a Phosphorus (P) source in intermittent rivers. Wequantified phosphorus composition of the most abundant fish species in a intermittent riverand temporal biomass change of these species to estimate P potentially released by fishmortality. Furthermore, we test whether fish carcasses were predated or not and identified fishscavengers in artificial river pools. The results shows a fish biomass temporal decrease in themiddle reach of the river only in the dry season very end. On the other hand, in the low riverreachs the overall fish biomass increase over time. Moreover, fish carcasses were highlypredated in artificial river pools. River intermittence can enhance the fish role as sink ofnutrients by different mecanisms that depends on the presence or absence of remanent pools.On the basis of these results, it can be concluded that fish carcasses in intermittent rivers arenutrient subsidies to terrestrial ecosystem in sites where total flow cease, whereas fish aresteady pool of Phosphorus capable to accumulate nutrients during dry season remanent riverpools sites. Tipo: Dissertação 2019-01-01T00:00:00Z