Yes / Building roofs represents a critical pathway for sediment mixing with rainwater. This study aims to explore the correlation between roof-top deposited sediment matter in the different areas of the Ikorodu Local Government Area in Lagos, Nigeria. The deposition rate on the roof was studied for 34 weeks in total (i.e., 17 weekly analyses in the rainy season and 17 weekly analyses in the dry season). The total deposition was collected by a 10 inch funnel and directed into a 5 L container, which was partially filled with sterilised water. The roof-top deposition in four different areas was inspected and analysed. The four areas were selected based on the levels of sanitation and vege-tation. The experimental results showed that the enumerated total depositions in different areas were higher in the dry season than the rainy season, with the highest deposition occurring in the Harmattan period. The data obtained from this study have evidenced that the contamination from roof-harvested rainwater can mainly be attributed to atmospheric deposition. Another key factor was the hygiene and sanitation of the harvesting areas, including the gutter, pipes and proximity to animal faeces.

Yes / Since the building roof acts as hub for atmospheric sediment deposition, the attached microbes can enter rainwater storage tank with ease to cause health issue for rainwater users. This study aims to explore the trend of roof-top deposited microbes in the different areas of Ikorodu local Government Area at Lagos, Nigeria. This paper also tests the hypothesis that the roof sediment deposition being a significant source to home bacteria. The total deposition rate on the roof for 34 weeks, which include 17 rainy and 17 dry weeks, were investigated. The enumerated bacteria was obtained from the roof deposit samples, where four representative different sites have been analysed to study the solid depositions and microbes within the area thoroughly. The sites were selected judging by their levels of sanitation and vegetation rate. The experimental investigations showed that enumerated microbes and total suspended solid (TSS) depositions in the different areas were higher in the dry season compared to rainy season, and the highest deposition was experienced in the Harmattan period. In addition, the results showed that areas with poor drainage infrastructure and poor sanitation have the roof-top deposition with higher bacterial count than good sanitation areas; while the unpaved and unvegetated areas produced higher deposits than the paved and vegetated areas. In terms of contamination sources, this study has illustrated that the particulate deposition on the roof-top prior to collection has further contaminated the roof-harvested rainwater.

Land ecosystems absorb about a quarter of all human emissions of carbon (C) by fossil fuel burning and land use change. This percentage varies greatly within years due to the land ecosystem response to climate variability and disturbance. Significant uncertainties remain in our knowledge of the magnitude and spatio-temporal changes in the land C sinks. The aims of my thesis are 1) to evaluate the capacity of different dynamic global vegetation models (DGVMs) to reproduce the fluxes and stocks of the land C cycle and 2) to analyse the drivers of change in the land C over the last two decades (1990-2009). In the first part of this thesis I evaluated the DGVM results over two regions: the Northern Hemisphere (NH) and the Tropics. Over the NH DGVMs tend to simulate longer growing seasons and a greater positive leaf area index trend in response to warming than that observed from satellite data. For the tropical region we found a high spatial correlation between the DGVMs and the observations for C stocks and fluxes, but the models produced higher C stocks over the non-forested areas. In the second part I studied the processes controlling the regional land C cycle. The findings can be summarized as: (1) the land CO2 sink has increased over the study period, through increases in tropical and southern regions with negligible change in northern regions; (2) globally and in most regions, the land sinks are not increasing as fast as the growth rate of excess atmospheric CO2 and (3) changes in water availability, particularly over the dry season, played a fundamental role in determining regional trends in NPP. My work seeks to improve our understanding of the relationship between the C cycle and its drivers, however considerable research is needed to understand the role of additional processes such as land use change, nitrogen deposition, to mention just a few.

This study investigated the effects of a seasonally variable forage resource on herbivore population dynamics. This involved estimating the relative importance of environmental conditions, and the accessible and used forage resources, at different stages of the seasonal cycle to herbivores in different life-stages and at different points in the reproductive cycle. This study was carried out in the Richtersveld region in South Africa, using goats kept by semi-nomadic Nama pastoralists. In the main study site, the Richtersveld National Park (RNP), herd movements follow a general seasonal migratory pattern: herds are based in the riparian zone of the Orange River during the dry season, and on plains away from the river in the wet season. Over 800 uniquely marked female goats in three life-stages (adults, yearlings and kids) were monitored over a three year period (2007 to 2009). These goats were weighed at 2 - 3 month intervals to provide an estimate of body condition. Browse availability in the riparian zone was estimated using measurements at an individual branch-level and a whole tree-level. FPAR satellite imagery was used to estimate forage abundance outside the riparian zone. Goat density was mapped for each week of the study using census data and the herd positions. Goat body condition, survival rates and fecundity rates for each life-stage were modelled as a response to forage availability, density and climatic conditions. The riparian zone in the RNP was found to function as the key resource of the RNP goat population. Forage depletion by goat browsing resulted in a negative feedback on goat body condition. This decline in body condition was directly related to lower adult survival over the dry season. Fecundity was also most influenced by dry season conditions through the negative effect of poor body condition on pregnancy rates and birth rates. Asymmetric competition between life-stages, resulting from the riparian browse profile being depleted from the bottom-up, was predicted to have a strong effect on goat demography by contributing to differences in body condition and survival rates between life-stages. Wet season conditions appeared to have little effect on goat population dynamics, either through increased neonate survival or through a mass carry-over effect influencing dry season survival. Goat body condition and vital rates were compared between the RNP and the neighbouring Kuboes rangeland, which does not have access to the Orange River, to assess the impact of differences in their dry season forage resource. The long-term size and variability of the livestock population in the RNP was also compared with livestock dynamics in Paulshoek, a rangeland 250 km south east of the RNP. The a priori predictions of relative population dynamics in each region, based on perceived differences in the nature of the key resource in each region, were largely supported.

Submitted by WESLEY LUIZ GUIMARÃES null (wesleylg_33@hotmail.com) on 2016-03-29T18:16:06Z No. of bitstreams: 1 Dissertação Wesley.pdf: 1407502 bytes, checksum: 9130791fa2c390f3a21fc1a95500ec67 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-03-30T18:16:01Z (GMT) No. of bitstreams: 1 guimaraes_wl_me_sjrp.pdf: 1407502 bytes, checksum: 9130791fa2c390f3a21fc1a95500ec67 (MD5) / Made available in DSpace on 2016-03-30T18:16:01Z (GMT). No. of bitstreams: 1 guimaraes_wl_me_sjrp.pdf: 1407502 bytes, checksum: 9130791fa2c390f3a21fc1a95500ec67 (MD5) Previous issue date: 2016-03-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Planícies de inundação são áreas úmidas onde podem ser encontradas as lagoas marginais. Devido ao período de seca e a sua baixa profundidade, estas lagoas podem apresentar caráter temporário com ocorrência sazonal. Tal perturbação pode levar algumas populações zooplanctônicas, como as de cladóceros, a entrarem em estado de dormência, produzindo os ovos de resistência que se depositam no sedimento seco formando um banco de ovos. Quando as lagoas voltam a encher, a comunidade de cladóceros rapidamente se reestabelece, provavelmente como resultado da eclosão dos ovos presentes no sedimento. Detectar espécies de cladóceros que produzem os ovos de resistência como estratégia para recolonização, bem como os fatores que influenciam a eclosão dos ovos, pode auxiliar na compreensão do papel do banco de ovos como fonte de biodiversidade zooplanctônica em lagoas marginais. O objetivo neste estudo foi verificar o potencial de cladóceros para recolonização de lagoas marginais temporárias, por meio da eclosão de ovos de resistência em condições experimentais específicas. A comunidade zooplanctônica foi amostrada em quatro lagoas marginais localizadas na planície de inundação do Rio Turvo. As amostragens dos cladóceros planctônicos foram feitas com rede de plâncton de 50 μm de malha, antes e após um período de seca. Além disso, também foram medidos parâmetros físicos e químicos: profundidade, transparência, temperatura, pH, condutividade, OD, clorofila e material em suspensão. Para a realização dos experimentos de eclosão dos ovos de resistência em laboratório, amostras do sedimento das lagoas foram obtidas com Corer (4,5 cm de diâmetro), durante a estação seca. Duas metodologias foram testadas para indicar qual a mais eficaz para a eclosão: 1. Tratamento ambiente: frascos com sedimento e água do rio Turvo mantidos em condições ambiente; 2. Tratamento câmara: frascos com sedimento e água do rio Turvo mantidos em condições controladas em câmara de germinação (23ºC e fotoperíodo 12:12). A cada dois dias cada réplica foi analisada quanto aos parâmetros físicos e químicos e para a verificação de cladóceros recém eclodidos. Após duas semanas estes procedimentos foram realizados semanalmente até completar 60 dias. Uma porção do sedimento foi utilizada para a caracterização quanto à granulometria. Antes da seca 23 espécies estavam presentes nas lagoas estudadas, após a seca 16 espécies. Durante o experimento de eclosão o tratamento Câmara obteve 431 eclosões enquanto o tratamento Ambiente obteve 118. Houve a eclosão das espécies Alona glabra, Ephemeroporus hybridus, Ilyocryptus spinifer, Leydigiops ornata, Notoalona sculpta e Oxyurella longicaudis, destas eclodiram 6 e 4 espécies no tratamento Ambiente e Câmara, respectivamente. No tratamento Câmara, após 7 dias, E. hybridus foi a primeira espécie a eclodir, e no tratamento Ambiente após 9 dias eclodiram as espécies I. spinifer e N. sculpta. Com a análise da partição hierárquica verificou-se que no tratamento Câmara a condutividade e o pH apresentaram uma correlação positiva com a eclosão dos ovos de resistência e o oxigênio dissolvido uma correlação negativa. No tratamento Ambiente, os parâmetros condutividade e oxigênio dissolvido apresentaram uma correlação negativa com a eclosão dos ovos. Em conclusão pode-se apontar que as espécies da família Chydoridae e Ilyocryptidae, que são organismos bentônicos ou litorâneos, apresentam um maior potencial para rapidamente eclodir em ambientes lacustres temporários. / Floodplains are wetlands where the oxbow lakes can be found. Due of the dry season and its shallow depth, these lagoons can present seasonal occurrence. Such disruption can lead some zooplankton populations, such as cladocerans, to enter in dormancy, producing resting eggs that are deposited in dry sediment forming a bank of eggs. When the lagoons back to fill the cladoceran community quickly restores, probably as a result of the hatch of eggs present in the sediment. To detect species of cladocerans that produce resting eggs as a strategy for recolonization, as well as the factors influencing the eggs hatch, may help understanding the egg bank's role as zooplankton biodiversity source in lagoons. Our goal in this study was to investigate the potential of cladocerans to recolonize of temporary lagoons, through the hatching of resting eggs in specific experimental conditions. The zooplankton community was sampled in four lagoons located in the Turvo River floodplain. Sampling of planktonic cladocerans were taken by a plankton 50 µm mesh net before and after the drying lagoons. Physical and chemical parameters as depth, transparency, temperature, pH, conductivity, OD, chlorophyll and suspended material were also measured. For the hatching experiments of resting eggs in laboratory, sediment from lagoons were sampled using a corer (4.5 cm diameter), during the dry season. Two methods were tested to indicate the most effective for the hatching: 1. Environment Treatment: bottles with sediment and water from the Turvo river kept at ambient conditions; 2. Chamber Treatment: bottles with sediment and water from the Turvo river kept under controlled conditions in a growth chamber (23 ° C and photoperiod 12:12). Every two days each replica was analyzed for physical and chemical parameters and the verification of cladocerans newly hatched. After two weeks these procedures were performed weekly to complete 60 days. A portion of the sediment was used for particle size characterization. Before the drought 23 species were present in the studied lagoons, after drought 16 species. During the hatching experiment Chamber Treatment had 431 hatching while Environment Treatment had 118. Six species hatched: Alona glabra, Ephemeroporus hybridus, Ilyocryptus spinifer, Leydigiops ornata and Notoalona sculpta and Oxyurella longicaudis, being four species in the Chamber Treatment and six species in the Treatment Environment. In the Chamber Treatment, after 7 days, E. hybridus was the first species to hatch, and after 9 days Environment Treatment N. sculpta and I. spinifer hatched. With the analysis of hierarchical partition we found that in the Chamber Treatment conductivity and pH showed a positive correlation and dissolved oxygen a negative correlation with the hatching of resting eggs. In the Environment Treatment, conductivity and dissolved oxygen showed a negative correlation with the eggs hatch. In conclusion we can point that species of Chydoridae and Ilyocryptidae family, which are benthic or littoral organisms have a greater potential to quickly hatch into temporary lacustrine environments.

Orientadores: Claudia Regina Baptista Haddad, Fernando Roberto Martins / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-18T12:00:54Z (GMT). No. of bitstreams: 1 Pereira_Luciano_M.pdf: 1574760 bytes, checksum: 86654daaeda73234eef3076e41dd937f (MD5) Previous issue date: 2011 / Resumo: Apesar da alta pluviosidade nas florestas tropicais, há grande variação na disponibilidade hídrica para as plantas. Em escala local, essa disponibilidade pode variar dependendo da localização dos indivíduos em clareiras, sua posição no relevo e a composição do solo. Em escala regional, variações relacionadas ao volume e distribuição das chuvas, aliadas às alterações climáticas sazonais, podem também gerar diferentes condições de déficit hídrico, aumentando as taxas de mortalidade das espécies arbóreas mais sensíveis, em especial no estádio de plântula. Considerando o cenário mundial de mudanças climáticas, torna-se urgente a compreensão dos mecanismos que determinam a ecologia das comunidades das florestas tropicais, principalmente em relação aos padrões de chuvas e secas. Neste trabalho analisamos as diferentes estratégias de resistência à seca de plântulas de espécies arbóreas, com o objetivo de entender como diferentes espécies arbóreas respondem à variação da disponibilidade hídrica, de modo a conhecer como essa variação filtra as espécies e conseqüentemente contribui para organizar a comunidade florestal. No primeiro capítulo apresentamos as principais estratégias de resistência à seca e as possíveis abordagens teóricas, descritas na literatura, para plântulas de espécies arbóreas, demonstrando a importância dessas estratégias na distribuição, abundância e coexistência de espécies nas florestas tropicais. As diferenças entre as florestas tropicais úmidas e secas, pelo baixo compartilhamento de espécies e os diferentes graus de resistência à seca apresentados por espécies arbóreas, indicam uma clara diferenciação de nichos. Espécies mais resistentes à seca ocupam, com maior abundância, locais mais secos, quando comparadas às espécies mais sensíveis, tanto em escala local quanto regional. Estratégias de resistência à seca podem ser de dois tipos: de tolerância à dessecação e de evitação à dessecação. No estádio de plântula, estratégias de tolerância parecem ser mais determinantes para a resistência à seca, principalmente a presença de caracteres que conferem tolerância a baixos potenciais hídricos, como resistência à cavitação. No segundo capítulo investigamos a hipótese de que há uma relação entre a abundância de algumas espécies em locais com diferentes intensidades de sombreamento e/ou sua posição na vertente (com provável gradiente hídrico) da Floresta Estacional Semidecídua e a presença de estratégias fisiológicas de trocas de gases relacionadas à resistência à seca. Avaliamos a troca de gases, dessecação e rebrota de plantas de duas espécies tardias (Esenbeckia leiocarpa e Astronium graveolens) e duas espécies pioneiras (Croton floribundus e Aegiphila selowiana) em um experimento de seca súbita em casa de vegetação. Encontramos maior resistência à seca nas espécies com maior abundância e de estádio sucessional tardio (E. leiocarpa e A. graveolens). A resistência à seca esteve associada às menores taxas de troca de gases, e as espécies com maior aproveitamento fotossintético exibiram menor resistência à seca. Essas espécies ocorrem mais abundantemente nos sítios de ocupação menos sombreados, reforçando a teoria de uma demanda conflitante para espécies que ou investem em resistência à seca ou na capacidade de aproveitamento de luz. A disponibilidade sazonal de água, assim como a diferença de luz entre as diferentes ecounidades, pode explicar a coexistência das espécies na floresta estacional / Abstract: The rainfall is high in tropical forests, but there is great variation in water availability to plants. On a local scale, this availability may vary depending on the location of individuals in gaps, their position in the landscape and soil composition. On a regional scale, variations related to the volume and distribution of rainfall, coupled with seasonal climatic changes, can also generate different water stress conditions, increasing the mortality rates of tree species most sensitive, especially at the seedling stage. Considering the global scenario of climatic changes, it is imperative to understand the mechanisms that determine the ecology of communities of tropical forests, especially in relation to patterns of rainfall and drought. We examined different strategies of drought resistance of seedlings of tree species, to determine the organization of the community and the contribution of water availability to the selection of species in these forests. The first chapter presents a review of the principal studies available on strategies for drought resistance in seedlings of tree species and the possible theoretical approaches, demonstrating the increasing importance of these studies for understanding the processes that determine the distribution, abundance and species coexistence in tropical forests. The differences between wet and dry tropical forests, in view of the low number of species in common and the different degrees of drought resistance presented by the tree species present, show a clear differentiation of niches. Species more resistant to drought present higher abundance in drier sites, compared to more sensitive species, at local and regional levels. Strategies for drought resistance may be of two kinds: desiccation tolerance and avoidance of desiccation. In the seedling stage tolerance strategies seem to be more crucial for resistance to drought, especially the presence of characteristics that confer tolerance to low water potentials, as resistance to cavitation. In the second chapter we investigated the hypothesis that there is a relationship between the existence of abundant species only at certain sites of the semi-deciduous forest and the presence of physiological strategies of gas exchange related to drought resistance. We evaluated the gas exchange process and desiccation and regrowth of plants of four species (Esenbeckia leiocarpa, Astronium graveolens, Croton floribundus and Aegiphila selowiana), during a sudden drought experiment in a greenhouse. E. leiocarpa, A. graveolens are late-successional species and C. floribundus and A. selowiana are pioneers species. We found greater resistance to drought in the most abundant and latesuccessional species. The drought resistance was associated with lower rates of gas exchange. Species with higher photosynthetic efficiency showed lower resistance to drought. These species occur most abundantly on sites less shaded, reinforcing the theory of a trade off between investment in drought resistance and ability to use light. The seasonal availability of water, similarly to differences between light of different eco-units, can explain species coexistence in the tropical seasonal forest / Mestrado / Biologia Vegetal / Mestre em Biologia Vegetal

The aim of the thesis was to evaluate of the impact of the proposed variants erosion and flood control measures on the retention capacity of landscape. The measure was evaluated in five variants. The retention capacity od the landspace was assessed of firect runoff. The volume of direct runoff was calculated using the CN method in two variants according to IPS and IPS II. The flood effect was evaluated using the DesQ-MaxQ program.

No description available.

O rio do Peixe, um dos principais afluentes do rio Tietê (Reservatório de Barra Bonita/Hidrovia Tietê Paraná), juntamente com seus formadores (microrregião geográfica de Botucatu - SP) constituem os principais mananciais das cidades que se localizam em suas bacias. A maior parte da bacia hidrográfica do rio do Peixe desenvolve-se sob rochas sedimentares arenosas, favoráveis às atividades de extração de areia, fato que aliado ao manejo incorreto do solo favorece a ocorrência de processos erosivos. Foram realizadas amostragens de água durante dez dias consecutivos e de sedimento durante três dias alternados, em dois períodos hidrológicos (seca e chuva), para a determinação de variáveis físicas, químicas e biológicas,com o objetivo principal de caracterizar do ponto de vista limnológico esse rio e sua foz. As análises das diferentes variáveis seguiram os métodos que são utilizados rotineiramente no Laboratório de Limnologia do CRHEA/EESC/USP. As águas do rio do Peixe apresentaram, principalmente altas concentrações de sólidos em suspensão. Os maiores valores de turbidez, condutividade, alcalinidade, HCO3-, CO3-, nitrito, nitrogênio amoniacal, nitrogênio Kjedhal, fosfato inorgânico, carbono orgânico e sólidos em suspensão foram obtidos durante o período de chuvas, influenciados principalmente pelo escoamento superficial que promove o carreamento de materiais da bacia hidrográfica. Foi possível ainda através das características limnológicas, agrupar as estações de amostragem ao longo do contínuo do rio em três regiões (alto, médio e baixo curso), e diferenciar do ponto de vista trófico as estações da foz com o rio Tietê. Um aumento da biomassa fitoplanctônica, no período de seca, no baixo curso do rio do Peixe foi favorecido pela menor vazão na barragem de Barra Bonita. / Peixe river, one of the main Tietê river\'s tributaries (Barra Bonita Reservoir/ Hydrovia Tietê Paraná), connected to its formers (geographic micro region of Botucatu- SP) are the main water sources to the cities located in their basins. Most of the Peixe river hydrographic basin runs through sandy sedimentary rocks, propitious to sand extraction activity. This fact, allied to improper use of the soil, lead to erosive processes occurrence. In the present work, water and sediment samples (dry and raining season) were taken during ten consecutive days and three alternate days, respectively. Physical, chemical and biological analyses were determined to characterize, under the limnological point of view, this river and its mouth; all these analysis were made following the methodology used in the Limnology Laboratory of CRHEA/EESC/USP. Peixe River waters showed high concentrations of suspended solids. The higher values of turbidity, conductivity, alcalinity, HCO3-, CO32-, nitrite, ammonium, Kjeldahl nitrogen, inorganic phosphate, organic carbon and suspended solids were obtained during the raining season, influenced by the surface water running that causes an input of material from the hydrographic basin. It was possible, by using the limnological characteristics, to duster the sampling stations throughout the river continuum in three regions: high, medium and low course, setting them apart from the Tietê\'s mouth sampling stations in account of distinct trophic state. Phytoplankton biomass increased during the dry season, in the low course of Peixe river, due to the lower flow towards Barra Bonita reservoir.

Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work was carried out in the county of Valen?a - RJ, with the objective to evaluate production and quality of the stargrass, in function of: two irrigation levels (with and without); four cut intervals (21, 28, 35 and 42 at the rainy season and 28, 35, 42 and 49 days at the dry season of the year); as well as four levels of nitrogen (0, 150, 300 e 600 kg/ha/year). The dry matter production (DMP) and the efficiency of the nitrogen utilization (ENU) in plots of 6,25 m2, were estimated from October 2004 to October 2005. In the months of January, June/July and September/October samples were collected to determine chemical composition and digestibility such as: crude protein (CP), neutral-detergent fiber (NDF) and in vitro dry matter digestibility (IVDMD). The Irrigation when increased DMP and ENU, reduced the forrage quality and only had significative effect (P<0,05) during the rainy season. The harvest intervals does not affected (P>0,05) on DMP. However, there was tendency to increase. Harvest intervals should be 42/49 days to obtain good forage quality and yield. The chemical composition and digestibility of the dry matter decreased with the spacing of the cuts and the effect of the interval of cuts on ENU was dependent of the irrigation. At that time it dries the irrigated treatments had her ENU increased with the decrease of the frequency of the cut. The nitrogen fertilization was the only factor that increased (P<0,05) DMP and the quality of the stargrass. However, the answer of DMP to the nitrogen fertilization was reduced and ENU was not affected in function of the nitrogen levels. In the conditions of experiment was realized, it is approved as the most appropriate handling of the studied factors: The interval of cuts of 42/49 days, that formed an alliance high yield with a satisfactory quality and the irrigation, only accomplished in favorable climatic conditions. / Este trabalho foi conduzido no munic?pio de Valen?a - RJ, com o objetivo de avaliar a produ??o e a qualidade do capim-estrela, em fun??o de: dois regimes h?dricos (irrigado e n?o-irrigado); quatro intervalos de cortes (21, 28, 35 e 42 na ?poca chuvosa e 28, 35, 42 e 49 dias na ?poca seca do ano); e quatro doses de nitrog?nio (0, 150, 300 e 600 kg/ha/ano). Durante o per?odo de outubro de 2004 a outubro de 2005, foram estimadas a produ??o de mat?ria seca (PMS) e a efici?ncia da aduba??o nitrogenada (EAN) em parcelas de 6,25 m2. Nos meses de janeiro, junho/julho e setembro/outubro coletaram-se amostras para a estimativa do valor nutritivo e digestibilidade, determinando a prote?na bruta (PB), a fibra em detergente neutro (FDN) e a digestibilidade in vitro da mat?ria seca (DIVMS). Os resultados mostraram que a irriga??o aumentou a PMS e a EAN, reduziu o valor nutritivo e DIV da mat?ria seca. Entretanto somente houve resposta (P<0,05) ao regime h?drico apenas quando as condi??es clim?ticas n?o foram limitantes ao crescimento da forrageira. O intervalo de cortes n?o alterou (P>0,05) a PMS, embora tenha sido observada a tend?ncia de incremento da mesma em fun??o da diminui??o da freq??ncia de cortes, sendo a maior produ??o obtida nos tratamentos 42/49 dias. A qualidade da forrageira diminuiu com o espa?amento dos cortes e o efeito do intervalo de cortes sobre a EAN foi dependente da irriga??o. Na ?poca seca do ano os tratamentos irrigados tiveram sua EAN aumentada com a diminui??o da freq??ncia do corte. A aduba??o nitrogenada foi o ?nico fator que aumentou (P<0,05), simultaneamente, a PMS e a qualidade do capim-estrela. No entanto, a resposta da PMS ? aduba??o nitrogenada foi pequena e a EAN n?o foi alterada (P>0,05) em fun??o das doses de nitrog?nio. Nas condi??es experimentais, preconiza-se como o manejo mais adequado: o intervalo de cortes de 42/49 dias, que aliou rendimentos elevados a uma qualidade satisfat?ria; e a irriga??o deve ser usada apenas quando as condi??es clim?ticas s?o favor?veis.