Indicators of soil degradation in urban forests: Physical and chemical parameters

The fragmentation of forest habitats in urban areas has aroused increasing interest in recent years according to the growing environmental problems. The fragmentation of theses ecosystems is caused, in general, by the pressure of housing, agriculture and industry, causing losses in biodiversity and problems of soil degradation in the border areas of theses remnants. The establishment of indicators of soil degradation becomes essential for the implementation of conservation and reclamation. This study analyzes physical and chemical characteristics of soil under different forms of vegetation in the forest surrounding the Quilombo Forest, located in Campinas/SP - Brazil, and examines the possibility of using these indices as indicators of environmental degradation in urban remnants. The parameters analyzed were: specific weight natural (γn), specific weight of solids (γs) Ca, P, K, Mg, pH, organic matter, H + Al, Sum of Base (SB) Percent Base Saturation (V%), Cation Exchange Capacity (CEC). The study shows that in general the different forms of land used in the study area significantly changed (or according to) the physical aspects of soil The porosity and voids of the soil stood out as the best indicators of soil physical degradation in the layer 0-20 cm deep. In relation to chemical indices, the soil under the cultivation of cane sugar had a significantly higher pH, K, Ca, Mg and sum of bases. The areas of forest showed higher levels of phosphorus, organic matter and CEC, indicating the importance of maintaining vegetation and replacement for the cycling of organic matter.

Recovery of degraded areas using topsoil in the Amazon rainforest

This study is aimed at evaluating the effect of placing the top soil cover areas, such as tailings degraded by tin mining, in the Amazon rainforest in Brazil. The evaluations of the planting sites occurred in areas where tin mining was carried out, basically planting native trees over a period of seven years. This work did not come from a pre-decreed methodology of experimental design, and data was collected only seven years after planting. Thus, it was not possible to identify all variables that contributed to a better recovery of the areas. Sampling was done about seven years after placing the top soil and is determined: pH, organic matter content, P, K, Ca, Mg, Al, cation exchange capacity (T), base saturation (V%), B, Fe, Zn, Cu and Mn. The native forest species existing at the site were evaluated in relation to height (in meters) and diameter of the base. For all sites where the surface layer of soil was applied, there were significant differences in the growth of native species. A fundamental aspect in the rehabilitation of areas degraded by mining, in general, is the knowledge about the soil where that recovery must be conducted. The specific procedures in the rehabilitation of those areas depend essentially on the physical, chemical, biological and mineralogical properties of the soil, which must present conditions for the adequate development of the plants. The initial idea of implanting a project of recovery of soils degraded by mining in the Amazon Forest emerged from a first visit to the field, carried out in 1998. The conditions of the already mined areas, in comparison to the exuberant forest of the surroundings caught our attention. The mining company that acts in the area had already been trying for some time to implant a plan of recovery of these mining areas, however without reaching any significant positive results. The loss of organic matter is one of the main problems of degraded areas in Brazil. The storage and reuse of a blanket of soil (topsoil) produce excellent results, but most of the miners consider this technique expensive and difficult because of operational costs and the sharp topographical condition of the mine site. Therefore, a research project was elaborated prioritizing the recovery of the soil degraded by the tin mining as a prior step to the recovery activities with native forest species. The formation of a superficial pseudo-horizon that supported the vegetation and the time that it would take for its establishment became the main objective of this research. The objective of this work is to verify the levels of elements and their traces in areas where top soils were applied for the remediation of degraded areas with local re-vegetation. © 2011 WIT Press.

Impacts of agricultural activities in remaining forest: Campinas/SP, Brazil

Forest fragmentation occurs normally in an area around the city or with high agricultural influence, such as the Forest of Quilombo that lies in Metropolitan Campinas/SP- Brazil. This forest is one such example since it is separated from the other forest fragments in the region for several types of human action. The objective of this study is to analyze the macro and micronutrients and soil edaphic insect fauna in the forest, pasture and sugar cane and inferring the impacts caused by the Mata do Quilombo cattle farming and urban expansion in chemical aspects of soil. Samples were collected in June/11, according to the procedure of method traps pitfall traps. In addition, at each sampling point four composite samples were collected for soil fertility analysis. Samples were collected at six points: pasture, degraded forest (near pasture), preserved forest (near pasture), degraded forest (near cane sugar), preserved forest (near cane sugar), and sugar cane sugar. The samples thus prepared were analyzed Ca, P, K, Mg, pH, organic matter, H + Al, Sum of Base (SB), Base Percentage Saturation (V%), Cation Exchange Capacity (CEC) and trace elements (S, B, Cu, Fe, Mg and Zn). Generally it can be seen that the group of organisms of soil fauna presented with little biodiversity. The number of individuals also shows little species, taxonomic groups showing the highest degree of impact that the remaining forest has suffered. Regarding the analysis of fertility it can be observed that the soil of the surrounding areas of the forest is under direct influence of agriculture. © 2013 WIT Press.

Influence of Agroforestry and Traditional Management of Maize (Zea mays L.) on Soil Fertility

The aim of the work was to evaluate soil nutrient concentration at 0-5, 5-10, and 10-20 cm in maize (Zea mays L.) grown in sequence with black oats (Avena strigosa Schreb.) under Leucaena diversifolia alley cropping agroforestry system (AFS) and traditional management system/sole crop (without trees-TS), following a randomized block design. The experiment was carried out at the Brazilian Association of Biodynamic Agriculture, in Botucatu, São Paulo, Brazil. The treatments were: control (C), chemical fertilizer (F), biomass of L. diversifolia alley cropping (B), and biomass of L. diversifolia alley cropping + chemical fertilizer (B+F). After 2 yr, it was observed that pH, organic matter, and nutrient content had a tendency to show higher values in the treatments biomass+fertilizer, biomass, and fertilizer application, in both systems. Higher values in pH, organic matter, phosphorus, potassium, calcium, magnesium, sum of bases, cation exchange capacity, percentage base saturation, boron, copper, and manganese tended to occur in the agroforestry system. © 2013 Copyright Taylor and Francis Group, LLC.

Caracterização da fertilidade do solo da composição mineral de espécies arbóreas de restinga do litoral paulista

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Atributos de latossolos e produtividade da cana-de-açúcar em decorrência da diversificação de culturas no período de reforma do canavial

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Atributos químicos em solos tratados com lodo biológico de indústria de gelatina

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Biomassa microbiana e atividade enzimática em solos do Estado de São Paulo sob vegetação nativa e cultivados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Variabilidade espacial de atributos do solo e da produtividade de milho

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Variabilidade espacial de atributos do solo em áreas intensamente cultivadas nas regiões de Jaboticabal e Monte Alto - SP

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Caracterização geoquímica e cerâmica das argilas do Grupo Itacaré / Formação Aquidauana, na faixa aflorante entre os estados de São Paulo e sul de Minas Gerais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Produção, qualidade e conservação pós-colheita de mandioquinha-salsa (Arracacia xanthorrhiza Bancroft) sob adubações mineral, orgânica e biodinâmica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo do uso de lodo de estações de tratamento de água e de esgoto urbano nas propriedades químicas do solo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Créditos de nitrogênio, alterações nos atributos químicos do solo e nos componentes de produção da cultura do milho em função da aplicação de esterco bovino

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Spatial distribution of Yellow Sigatoka Leaf Spot correlated with soil fertility and plant nutrition

This study analyzed the spatial distribution of Yellow Sigatoka Leaf Spot relative to soil fertility and plant nutritional status using geostatistics. The experimental area comprised 1.2 ha, where 27 points were georeferenced and spaced on a regular grid 18 × 18 m. The severity of Yellow Sigatoka, soil fertility and plant nutritional status were evaluated at each point. The spherical model was adjusted for all variables using restricted maximum likelihood. Kriging maps showed the highest infection rate of Sigatoka occurred in high areas of the field which had the highest concentration of sand, while the lowest disease was found in lower areas with lower silt, organic matter, total exchangeable bases, effective cation exchange capacity, base saturation, Ca and Mg in soil, and foliar sulfur (S). These results may help farmers manage Yellow Sigatoka disease more effectively, with balanced fertilization and reduced fungicide application. This practice minimizes the environmental impact and cost of production while contributing to production sustainability.