Resumo -Métodos para avaliar a atividade microbiana no solo são fundamentais no monitoramento ambiental de áreas degradadas. O objetivo deste trabalho foi investigar a atividade microbiana de solo do semi-árido cultivado com Atriplex nummularia Lindl. em áreas que receberam rejeito salino durante um e três anos, em comparação com um solo nativo, sem cultivo e não irrigada. O solo cultivado por três anos e que recebeu rejeito salino apresentou, no período seco, valores de pH, CE e atividade de hidrólise do diacetato de fluoresceína (FDA) superiores aos das demais áreas. No entanto, foi observada correlação negativa entre o carbono microbiano e os valores do quociente metabólico (qCO 2 ). A biomassa microbiana e a fosfatase alcalina também foram superiores no solo cultivado por três anos e que recebeu rejeito salino em relação ao solo nativo sem irrigação, confirmando o desempenho de plantas halófitas na melhoria da qualidade do solo sob condições de estresse salino. O cultivo de A. nummularia constitui uma das alternativas para utilização de rejeito salino proveniente da dessalinização por osmose reversa.Termos para indexação: emissão de CO 2 , biomassa microbiana, diacetato de fluoresceína, fosfatase alcalina. Microbial activity in a semiarid soil cultivated with Atriplex nummulariaAbstract -Methods used to estimate the soil microbial activity are important to environmental monitoring of degraded areas. The objective of this research was to investigate the microbial activity of a semiarid soil cultivated with Atriplex nummularia Lindl. in a field receiving saline waste during one and three years, in comparison with an area without crop and irrigation. Soil cultivated during three years presented, during the dry season, values of pH, CE, and activity of FDA hydrolyses higher than those registered in other areas. However, a negative correlation between the microbial carbon and values of qCO 2 was observed. The microbial biomass and the alkaline phosphates were also higher in the three years cultivated soil, in comparison with the native soil, non irrigated, confirming the role of halophytes for enhancing quality of soils under saline stress. Thus, the cultivation of A. nummularia is an alternative for using saline waste from the desalinization process.

Problem statement: Mining activities involve the removal of the vegetal cover and the soil organic layer, causing a severe environmental impact. In Northeast Brazil, 40% of the world's crude gypsum is found in a semiarid area, making this region responsible for 95% of the gypsum demand in the national market. Although economically important, this activity is harmful to the environment. Studies of soil microbiological and biochemical attributes can help in the identification of the limitations of impacted ecosystems, providing data to define strategies for sustainability of such environments. Approach: To evaluate and compare the biological state of preserved and mining degraded semiarid soils, a native preserved area and areas impacted by gypsum mining were selected at the Araripina Experimental Station, located in the semiarid region of Pernambuco State, Northeast Brazil. The four sampling areas included: (1) A native, preserved "caatinga" area with spine bearing trees and shrubs and some characteristic xerophytic plants (AN); (2) An area surrounding the mine, presenting the same type of vegetation although already degraded (AM); (3) A waste deposit area (AR); (4) Interface area between the waste deposit and a mining degraded area (AI). Samples were taken in each area (1000 m 2 ) during two periods: wet (December/2003, Rainfall = 28.7 mm) and dry (September/2004, Rainfall = 1.3 mm). Results: Fluorescein diacetate hydrolysis values, microbial biomass C and basal respiration were higher in the preserved "caatinga" than in the impacted areas. The gypsum mining activity reduced the concentration of easily extractable glomalin in relation to the native "caatinga" area in both sampling periods. Higher deposits of total glomalin also occurred in the native area, however, mainly during the wet period. Conclusion: The mining activity produced a negative impact on the soil microbiota, reducing the total enzymatic activity. The microbial biomass was significantly lower in the waste deposit area than in the native and interface areas. The results indicated that the mining activity is harmful to the soil microbiota in this area and that glomalin can be a useful indicator of soil disturbance.

The goals of this study were to evaluate the microbial activity, arbuscular mycorrhizal fungi and inoculation of woody plants (Caesalpinia ferrea, Mimosa tenuiflora and Erythrina velutina) in lead contaminated soil from the semi-arid region of northeastern of Brazil (Belo Jardim, Pernambuco). Dilutions were prepared by adding lead contaminated soil (270 mg Kg-1) to uncontaminated soil (37 mg Pb Kg soil-1) in the proportions of 7.5%, 15%, and 30% (v:v). The increase of lead contamination in the soil negatively influenced the amount of carbon in the microbial biomass of the samples from both the dry and rainy seasons and the metabolic quotient only differed between the collection seasons in the 30% contaminated soil. The average value of the acid phosphatase activity in the dry season was 2.3 times higher than observed during the rainy season. There was no significant difference in the number of glomerospores observed between soils and periods studied. The most probable number of infective propagules was reduced for both seasons due to the excess lead in soil. The mycorrhizal colonization rate was reduced for the three plant species assayed. The inoculation with arbuscular mycorrhizal fungi benefited the growth of Erythrina velutina in lead contaminated soil.

The triazines are a group of herbicides with a wide range of uses. Atrazine is, in fact, one of the most used agricultural pesticides in the world. The terbuthylazine is applied as a substitute of atrazine in some countries of Europe since 2004, when the European Union announced a ban of atrazine because of ubiquitous water contamination. In this study, both atrazine and terbuthylazine were degraded by the ozone process to estimate the efficiency on pesticide removal in water, the intermediates formed and their potential oestrogenic activity using the yeast oestrogen screen (YES) test. Both pesticides were rapidly eliminated from the medium during ozonation (applied ozone dose 0.083 and 0.02 mmol O3 L(-1), respectively). The results show that both compounds generated similar by-products from ozone degradation. Moreover, significant oestrogenic activity was detected for both atrazine and terbuthylazine intermediates, during the first minutes of ozonation. The YES assay used in this study proved to be a sensitive tool in assessing trace amounts of oestrogenic chemicals, which can represent critical issues influencing the experimental results in environmental applications.

A expansão de áreas agrícolas e urbanas, a implementação de projetos industriais, entre outras atividades antrópicas, promovem a alteração da paisagem original, criando outra, dominada por vários remanescentes da vegetação nativa. Estes remanescentes, denominados também de fragmentos florestais, são fundamentais para manutenção da biodiversidade existente no local. Porém uma paisagem fragmentada torna os remanescentes florestais isolados vulneráveis, nesse sentido, torna-se importante a concepção de conexões para interligar os fragmentos, diminuindo a pressão sobre sua diversidade e aumentando o fluxo de espécies, o fluxo gênico e a quantidade e qualidade dos hábitats existentes. Uma das formas de interconexão possíveis é a criação de corredores ecológicos, interligando os fragmentos, portanto, este estudo tem como objetivo indicar áreas para o estabelecimento de corredores ecológicos, por meio de um Sistema de Informações Geográficas (SIG), segundo critérios relacionados ao uso e ocupação do solo na Zona de Preservação Ecológica do Complexo Industrial Portuário Eraldo Gueiros - Suape (CIPS). Para tanto, foram utilizados atributos ambientais (variáveis), aos quais foram atribuídos pesos matemáticos e analisados por meio de geoprocessamento. Os resultados encontrados nesse estudo denotam a importância do uso do SIG como uma importante ferramenta para análise de áreas em grande escala, as áreas recomendadas para a implementação de corredores por meio da análise de geoprocessamento foram compatíveis com análises realizadas na paisagem, sendo que os pesos dados as variáveis foram eficientes em agrupar os atributos biológicos, físicos e antrópicos, resultando em conexões possíveis de serem realizadas em campo.    A B S T R A C T The expansion of agricultural and urban areas, the implementation of industrial projects, among other human activities promote the alteration of the original landscape and creates another dominated by several remnants of native vegetation. These remnants, also called forest fragments are essential to maintain local biodiversity. But the isolated forest remnants in a fragmented landscape become vulnerable. Thus the design of connections for linking the fragments becomes important to reduce the pressure on its diversity and increase the flow of species, gene flow and the quantity and quality of existing habitats. One way of interconnection possible is the creation of ecological corridors, linking the fragments. Therefore this study aims to indicate areas to the establishment of ecological corridors through a Geographic Information System (GIS), following criteria related to the use and occupation of soil of Ecological Preservation Zone in Complexo Industrial Portuário Eraldo Gueiros - Suape (CIPS). To this end, we used environmental attributes (variables) that have been assigned mathematical weights and analyzed using geoprocessing. The result in this study show the importance of using GIS as an important tool for analyzing large-scale areas. The areas recommended for implementation of corridors through the analysis of GIS were consistent with analysis undertaken in the landscape with the weights data variables were efficient to group biological, physical and antropic attributes, resulting in connections that can be developed in the field. Keywords: Ecological corridor, Atlantic fores, Interconection of fragment, Protection of ecosystems.