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This study presents the results of the soil hydraulic characterization performed under three land covers, namely pasture, 9-year-old restored forest, and remnant forest, in the Brazilian Atlantic Forest. Two types of infiltration tests were performed, namely tension (Mini-Disk Infiltrometer, MDI) and ponding (Beerkan) tests. MDI and Beerkan tests provided complementary information, highlighting a clear increase of the hydraulic conductivity, especially at the remnant forest plots, when moving from near-saturated to saturated conditions. In addition, measuring the unsaturated soil hydraulic conductivity with different water pressure heads allowed the estimation of the macroscopic capillary length in the field. This approach, in conjunction with Beerkan measurements, allowed the design better estimates of the saturated soil hydraulic conductivity under challenging field conditions, such as soil water repellency (SWR). This research also reports, for the first time, evidence of SWR in the Atlantic Forest, which affected the early stage of the infiltration process with more frequency in the remnant forest.

Soil water tension was measured 22 times through a 50 day period, in a transect with 48 sets of tensiometers at five depths. General variability and temporal stability of this property as well as the spatio-temporal dependence of its variability were evaluated. The whole data set was divided into subsets according to location and time of measurement. The variability of soil water tension could be explained by a temporal trend (macro variation) and a random-like micro-variation. The tension values increased similarly for all locations along the measured period, and exhibited strong temporal stability, which was higher at the top layers. It was possible to identify and model spatio-temporal dependence of the variability. The spatial variograms for the sub-sets presented higher uncertainties, but were very similar to each other. Temporal dependence was clearly identified for transformed data, although larger differences were found between sub-sets. Very good agreement was found between the actual and the estimated data using the product–sum model for the spatio-temporal dependence. The procedure seems suitable for combining the spatial and temporal scales to expand the description of the variability dependence of soil hydraulic properties.

AIM: The main goal of this research was to investigate the influence of the hydrological pulses on the space-temporal dynamics of physical and chemical variables in a wetland adjacent to Jacupiranguinha River (São Paulo, Brazil); METHODS: Eleven sampling points were distributed among the wetland, a tributary by its left side and the adjacent river. Four samplings were carried out, covering the rainy and the dry periods. Measures of pH, dissolved oxygen, electrical conductivity and redox potential were taken in regular intervals of the water column using a multiparametric probe. Water samples were collected for the nitrogen and total phosphorus analysis, as well as their dissolved fractions (dissolved inorganic phosphorus, total dissolved phosphorus, ammoniacal nitrogen and nitrate). Total alkalinity and suspended solids were also quantified; RESULTS: The Multivariate Analysis of Variance showed the influence of the seasonality on the variability of the investigated variables, while the Principal Component Analysis gave rise in two statistical significant axes, which delimited two groups representative of the rainy and dry periods. Hydrological pulses from Jacupiranguinha River, besides contributing to the inputs of nutrients and sediments during the period of connectivity, accounted for the decrease in spatial gradients in the wetland. This "homogenization effect" was evidenced by the Cluster Analysis. The research also showed an industrial raw effluent as the main point source of phosphorus to the Jacupiranguinha River and, indirectly, to the wetland; CONCLUSIONS: Therefore, considering the scarcity of information about the wetlands in the study area, this research, besides contributing to the understanding of the influence of hydrological pulses on the investigated environmental variables, showed the need for adoption of conservation policies of these ecosystems face the increase anthropic pressures that they have been submitted, which may result in lack of their ecological, social and economic functions. OBJETIVO: O objetivo desta pesquisa foi investigar a influência dos pulsos de inundação sobre a dinâmica espaço-temporal de variáveis físicas e químicas em uma área alagada adjacente ao Rio Jacupiranguinha (São Paulo, Brasil). Onze pontos de amostragem foram distribuídos entre a área alagada, incluindo um tributário pela margem esquerda e o canal do rio adjacente; MÉTODOS: Quatro campanhas de amostragem foram realizadas, cobrindo os períodos seco e chuvoso. Medidas de pH, oxigênio dissolvido, condutividade elétrica e potencial redox foram realizadas em intervalos regulares da coluna d'água usando uma sonda multiparâmetros. Amostras de água foram coletadas para análise de nitrogênio e fósforo total, além de suas frações dissolvidas (fósforo inorgânico dissolvido, fósforo total dissolvido, nitrogênio amoniacal e nitrato). Alcalinidade total e sólidos suspensos também foram quantificados; RESULTADOS: A Análise Multivariada de Variância mostrou influência da sazonalidade sobre a variabilidade das variáveis investigadas, enquanto que a Análise de Componentes Principais deu origem a dois eixos estatisticamente significativos, os quais delimitaram dois grupos representativos dos períodos seco e chuvoso. Os pulsos hidrológicos do Rio Jacupiranguinha, além de contribuírem para o aporte de nutrientes e sedimentos durante o período de conectividade, foram responsáveis pela diminuição dos gradientes espaciais na área alagada. Este "efeito de homogeneização" foi evidenciado pela Análise de Cluster. A pesquisa também mostrou um efluente bruto industrial como a principal fonte pontual de fósforo para o Rio Jacupiranguinha e, indiretamente, para a área alagada; CONCLUSÕES: Portanto, considerando a escassez de informações sobre os ecossistemas aquáticos da área de estudo, esta pesquisa, além de contribuir para o entendimento da influência dos pulsos hidrológicos sobre as variáveis ambientais da área alagada investigada, mostrou a necessidade da adoção de medidas de conservação destes ecossistemas frente crescente pressão antrópica a que estão submetidos, as quais podem resultar em perdas de suas funções ecológicas, sociais e econômicas.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:50:05Z No. of bitstreams: 1 S0100-69162006000100010.pdf: 144323 bytes, checksum: f75e45b2152ee62446dbc6d60773d5d7 (MD5) Made available in DSpace on 2013-08-22T18:50:05Z (GMT). No. of bitstreams: 1 S0100-69162006000100010.pdf: 144323 bytes, checksum: f75e45b2152ee62446dbc6d60773d5d7 (MD5) Previous issue date: 2006-04-01 Made available in DSpace on 2013-09-30T19:40:42Z (GMT). No. of bitstreams: 2 S0100-69162006000100010.pdf: 144323 bytes, checksum: f75e45b2152ee62446dbc6d60773d5d7 (MD5) S0100-69162006000100010.pdf.txt: 32104 bytes, checksum: 6557cca4b1d07ae15e81f086982d9801 (MD5) Previous issue date: 2006-04-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:17:07Z No. of bitstreams: 2 S0100-69162006000100010.pdf: 144323 bytes, checksum: f75e45b2152ee62446dbc6d60773d5d7 (MD5) S0100-69162006000100010.pdf.txt: 32104 bytes, checksum: 6557cca4b1d07ae15e81f086982d9801 (MD5) Made available in DSpace on 2014-05-20T13:17:07Z (GMT). No. of bitstreams: 2 S0100-69162006000100010.pdf: 144323 bytes, checksum: f75e45b2152ee62446dbc6d60773d5d7 (MD5) S0100-69162006000100010.pdf.txt: 32104 bytes, checksum: 6557cca4b1d07ae15e81f086982d9801 (MD5) Previous issue date: 2006-04-01 O presente trabalho teve por objetivo avaliar o efeito da subsolagem e da adubação verde nas propriedades físicas de um Latossolo Vermelho distrófico típico, cultivado com citros (laranjeira Valência). Os tratamentos empregados foram: manejo mecânico das plantas invasoras com roçadora (Testemunha); subsolagem em um lado da planta na entrecopa; subsolagem nos dois lados da planta na entrecopa, e semeadura direta de Crotalaria spectabilis na entrecopa. As propriedades físicas do solo avaliadas foram: porosidade total, macroporosidade, microporosidade, densidade, resistência mecânica à penetração vertical e condutividade hidráulica. Na avaliação efetuada na safra 2001-2002, obtiveram-se os maiores valores de densidade do solo e resistência do solo à penetração vertical, e os menores valores de macroporos e condutividade hidráulica do solo nas entrecopas com e sem tráfego no pomar, em relação à região da copa, principalmente na camada de 0,0-0,2 m de profundidade. Os tratamentos aplicados não surtiram efeitos positivos significativos nas propriedades físicas do solo. The present work was conducted to evaluate the effects of subsoiling and green manuring on soil physical properties of a Typical Haplustox soil cultivated with Valencia orange trees. The treatments applied were mechanic management of the invaders plants with shredder (witness); subsoiling in one side of the plant on between crown; subsoiling on both sides of the plant on between crown and direct seeding of Crotalaria spectabilis on between crown. The soil physical properties evaluated were porosity, macro porosity, micro porosity, bulk density and mechanical resistance to vertical penetration and hydraulic conductivity. The evaluation effectuated to the harvest in 2001/2002, got the greatest values of bulk density and soil resistance to vertical penetration, and the least values of macro porosity and soil hydraulic conductivity on the region between crown, with and without traffic in relation to the crown, especially on the layer 0.0-0.2 m of depth. The treatments used did not result in positive significative effects on the soil physical properties. UNESP Departamento de Solos e Adubos UNESP Departamento de Solos e Adubos