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Ecosystems provide various environmental services such as key recharge and ow of the water resource, but they can be damaged by human activity. Understanding vegetation cover allows administrators to predict the effects of such changes on groundwater and the actions needed in ad- ministration. Grecia Forest Reserve is a 2000-hectare zone in Costa Rica that affects eleven settlements in the region. There we measured vegetation cover and water volume in all water springs (N=70). We identified four vegetation groups: secondary forest, scrubland, pasture and pine forest; and an overall mean ow of 1,12 l/s/ha. Most water springs were found in secondary forest, which had the highest vegetation cover; however, scrublands had higher flows.

A ocupação desordenada do solo, assim como a ausência de práticas conservacionistas, têm levado à degradação dos recursos naturais. Nesse contexto, tem se atribuído às florestas ripárias presentes nas áreas de preservação permanente o efeito de uma panaceia na proteção dos recursos hídricos. Neste artigo, por meio de uma revisão, tenta-se esclarecer os efeitos hidrológicos da recuperação das florestas situadas nessas áreas, no que concerne à quantidade de água e à manutenção dos recursos hídricos no contexto de microbacias hidrográficas. Mostra-se a influência das florestas, de uma maneira geral, sobre a quantidade de água e o regime de vazão em bacias hidrográficas. Na sequência, evidencia-se que as florestas ripárias possuem efeito hidrológico similar ao das florestas de uma maneira geral. Entretanto, com o objetivo de garantir a proteção dos recursos hídricos, salienta-se que, para bacias com cobertura do solo diferente de florestas naturais, mais importante do que restaurar florestas nas áreas de preservação permanente é manter altas taxas de infiltração de água no solo. Nesse sentido, como as bacias hidrográficas são heterogêneas em vários aspectos (tipos de solos, declividade, uso da terra) não é possível obter uma proteção efetiva e integral da água simplesmente realizando o plantio de espécies características de zonas ripárias em áreas de preservação permanente, mas sim manejando bacias hidrográficas como um todo. Por último, apontam-se algumas lacunas sobre as quais a hidrologia pode ajudar a ampliar o conhecimento do papel hidrológico das florestas ripárias em microbacias hidrográficas.The lack of soil occupation planning, as well as the absence of soil conservation, have caused natural resources degradation. In this context, riparian forests located within the permanent preservation areas are described as a panacea for water resources protection. In this paper, we clarify the hydrological effects of these forests focusing on water quantity and water resources maintenance in small catchments. After, is shown that riparian forests present the same hydrological effect of forests in general. However, aiming to guarantee water resources protection we point out that for catchments with land uses that are not natural forests, the most important action is to maintain the high water infiltration rates. As catchments present high variability regarding the soil, topography, land use, it is not possible to obtain effective water protection by simply restoring forests in the permanent preservation areas, but we do obtain it by managing the whole small catchment. Last but not least, we exhibit some gaps that hydrology may contribute to fill in an effort to increase the knowledge of riparian forests role in small catchments.

Soil samples were collected from 8 land use types in Embu to study the effects of land use on soil chemical and physical parameters and on the occurrence of Trichoderma spp. The fungus was recovered from the soil using the dilution plate and soil washing technique. The remaining soil samples were used to measure the following characters of the soil; pH was determined in 1:1 (w/v) soil – water suspension with pH meter, total nitrogen was determined by the Kjeldahl method, available nutrients P, K, Na, Ca and Mg were determined using Mehlich method while total organic carbon was determined by calorimetric method. Land use type (LUT), plant cover, and soil physical and chemical properties influenced Trichoderma occurrence. The frequency of isolation of Trichoderma spp. was highest in napier LUT followed by indigenous forests. Carbon, N, Mg and Fe loaded with forest land use type suggesting their influence on fungal diversity in this LUT. The forests had clay loam soils with higher porosity and water retention capacity compared with the cultivated LUTs which were characterized with clay soils and bulk density. Napier together with other cultivated LUTs which had low records of the fungus loaded positively with Mn and Cu. This implied that plant type was the major determining factor for the high population of Trichoderma recorded in napier LUT. The diversity of soil factors observed in the fallow lands explained the influence of land management on soil physical and chemical characteristics which in turn determined the fungal distribution. Soil depth (0-20cm) did not influence soil factors though fungal diversity, abundance and evenness varied with depth suggesting the influence of other drivers.This study explains the fact that many factors interact in determining the occurrence of Trichoderma spp. and that in some situations it is the soil that is the key factor determining fungal occurrence and diversity while in others it is the plant type.

The process of agricultural modernization that in happened in Rio Grande do Sul, begun in the decades of 1960 and 1970, it generated considerable transformations so much in the system of agricultural production as in the space reorganization of the areas returned to the primary section. This way, this research chose as laboratory of studies, two districts: Santa Teresinha and São Bento. The methodology was based on the accomplishment of bibliographical rising regarding the fear proposed, as well as field work. In this sense, the modernization process, analized in this research whit the support of geoprocessing technique, in the sense of verifying the current uses and occupations of both districts, came as an important instrument, in which cannot him to identify, the different space cuttings tha wa verified in elapsing of this research.

As rodovias desempenham função importante no processo de estruturação das cidades, por facilitar os deslocamentos interurbanos. No entanto, quando absorvidas pela malha urbana de uma cidade, essas rodovias desenvolvem dinâmicas particulares com o espaço intraurbano no qual estão inseridas, com alterações na acessibilidade, na morfologia e no uso e ocupação da terra urbana. Com base nesse contexto, este artigo tem por objetivo analisar as dinâmicas entre a implantação do contorno rodoviário da BR-230 e o processo de produção do espaço intraurbano da cidade de João Pessoa-PB, entre os anos de 1963 e 2013, em termos de morfologia, uso e ocupação do solo urbano. O método empregado foi o da Lógica Evolutiva do Tecido Urbano, que divide a evolução urbana em três estágios: superação de limites, crescimento e combinação/conflitos. O método foi associado a ferramentas analíticas, como a Sintaxe Espacial e softwares de Sistema de Informação Geográfica. Os resultados mostram que a rodovia impulsionou o espraiamento da cidade para o setor sul e produziu uma malha urbana tentacular, onde também se identificou o padrão de crescimento horizontal e fragmentado, alterações na acessibilidade, uso do solo e na segregação socioespacial.