http://repositorio.ufc.br/handle/riufc/324 2026-04-08T09:19:23Z 2026-04-08T09:19:23Z Duarte, Maria Rita Nascimento http://repositorio.ufc.br/handle/riufc/85398 2026-03-18T16:49:46Z 2022-01-01T00:00:00Z

Título: Efeito do uso e ocupação do solo sobre as variáveis limnológicas e a composição da comunidade em um rio intermitente Autor(es): Duarte, Maria Rita Nascimento Abstract: The consequences of human activities on water resources have had repercussions on theway and quality of life of populations and communities of aquatic organisms, affectingthe environmental balance of areas drained by hydrographic basins, thus contributing tochange their landscapes at local scales, regional and global. The Intermittent rivers arecharacteristic for their flow variability, due to alternations between the two extremes offlow, flooding and drying, which create complex mosaics of dry channels and lenticwaters. Intensive land use raises concerns about the threats posed by anthropogenichydrological changes to the ecological integrity of intermittent rivers. Given the context,our study aims to assess how land use and occupation influence limnological variablesand the composition of communities in an Intermittent River. In chapter 1, we evaluatedthe dynamics of the physical, chemical and biological variables of the waters of anintermittent river and of an artificial surface reservoir through multivariate analysis andin response to the use and occupation of the soils of its hydrographic basin. The studywas carried out in the Cruxati River watershed in four study areas (three river areas andone artificial reservoir) and the images were obtained from the Landsat-8 satellite OLIsensor. The limnological variables measured were: pH, electrical conductivity, dissolvedoxygen, turbidity, nutrients (total nitrogen and total phosphorus) and chlorophyll a.Limnological variables were analyzed using Principal Component Analysis - PCA,Tukey's test and Cluster Analysis. The eutrophication of the studied areas was calculatedusing the Trophic State Index. The PCA allowed the selection of three componentsindicating the quality of surface water, river and artificial reservoir, explaining 88.57%of the total variance. The limnological variables responsible for the grouping were:electrical conductivity; dissolved oxygen and turbidity. The use and occupation of thesoil influenced the water quality of the river stretches. Anthropization influenced thedissolved oxygen content and the presence of arable areas caused an increase in turbidity.However, the most conserved landscape (artificial reservoir) was the one with the highestdegree of eutrophication due to the difference in hydrological dynamics between lenticand lotic environments. In chapter 2, evaluated the historical effects of land use andoccupation on limnological variables and the composition of aquatic macroinvertebratesand fish in six Intermittent microbasins. For this purpose, land use and land cover mapswere made, as watersheds 4, 5 and 6 have been going through a process of intensedeforestation and an increase in non-vegetated and agricultural areas, adding an alert tothe compromise of environmental quality and to the management of water resources inthe semi-arid region. Tipo: Tese

2022-01-01T00:00:00Z Holanda, Alyne Bezerra Tabosa de http://repositorio.ufc.br/handle/riufc/85071 2026-03-04T19:59:50Z 2025-01-01T00:00:00Z

Título: Modelagem de distribuição da herpetofauna nos brejos de altitude do setor setentrional do semiárido brasileiro a partir do pleistoceno superior Autor(es): Holanda, Alyne Bezerra Tabosa de Abstract: The Brazilian semi-arid region, which encompasses the Caatinga biome, is situated betweentwo humid biomes—the Amazon Rainforest and the Atlantic Forest—and is characterized bythe occurrence of isolated humid environments that constitute important habitats for the localherpetofauna. This region experienced climatic shifts during the Quaternary, which influencedthe spatial distribution of humid forests. The present study examined the distribution ofherpetofaunal species groups adapted to humid enclaves within the Brazilian semi-arid regionusing species distribution modeling, focusing on the Last Interglacial (~120 ka), the LastGlacial Maximum (~22 ka), and the Mid-Holocene (~6 ka). Paleoclimatic data obtained fromWorldClim 1.4 were employed in the analyses. The models demonstrated strong discriminatoryperformance for the variables associated with each taxonomic group (maximum temperatureof the warmest month for lizards and snakes, and annual precipitation for anurans), in additionto high rainfall totals, which were relevant for all groups. Amphibians exhibited a greaterdependence on humid ecosystems, with their distributions being markedly affected during drierperiods. Lizards and snakes, in contrast, showed higher ecological tolerance, resulting inbroader distributions under these drier climatic scenarios. Overall, species distributionscontracted by approximately 35% (lizards) to 61% (snakes) during the Last Interglacial,whereas amphibians experienced a reduction of 73% relative to their current distribution. Tipo: Tese

2025-01-01T00:00:00Z Moreno, Juan Guillermo Cadena http://repositorio.ufc.br/handle/riufc/84684 2026-02-10T14:33:00Z 2024-01-01T00:00:00Z

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 Nascimento, Sandro Ferreira do http://repositorio.ufc.br/handle/riufc/84430 2026-01-22T16:57:10Z 2025-01-01T00:00:00Z

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