PRODUÇÃO DE SERRAPILHEIRA E O RETORNO DE MACRONUTRIENTES EM FLORESTA PLUVIAL ATLÂNTICA - ESTAÇÃO BIOLÓGICA DE BORACÉIA (SÃO PAULO - BRASIL)

Estudou-se na Floresta Pluvial Atlântica. na Estação Biológica de Boracéia, durante 24 meses, a produção de serrapilheira, avaliando-se a paricipação percentual apresentada pelas diferentes frações que a compõem. Neste estudo. optou-se em dividir a serrapilheira nas frações folhas, ramos e outros componentes, tais como flores. frutos e sementes. A produção anual da scrrapilhcira foi de 6054,10 kg ha-1, onde a fração folhas contribuiu com 72,73%; ramos, com 16.09% e outros componentes com 11,29%. A produção mensal da serrapilheira apresentou sazonal idade inconspícua. As concentrações de macronutricntcs, na serralheira corresponderam a: N = 1,73%; P= 0,06%, K = 0,26%, Ca = 0,54%, Mg = 0,23% e S = 0,18% e a transferência média de nutrientes via serrapilheira, em kg.ha-1.ano-1, foi de 105,24 de N; 3,41 de P; 14,76 de K; 32,83 de Ca; 14,72 de Mg e 11,69 de S

Biogeoquímica de uma microbacia após o corte raso de uma plantação de eucalipto de 7 anos de idade

This work studied the effect on nutrient cycling and quantities of mineral nutrients exported with the woody biomass after the clearcutting of a 7-year old plantation of Eucalyptus saligna Smith. The experiment was carried out on lands of Votorantim Celulose e Papel S/A, Fazenda Bela Vista III, located in the municipality of Santa Branca, State of São Paulo, with coordinates 25°25' South and 45°54' West from Greenwich, and 695m average altitude. The climate is classified as Cwa type, according to Köeppen, and is characterized by dry winter temperatures, and by an annual average precipitation of 1,562mm. The soils in the region are predominantly of the Hapludulf type. The experimental catchment has an area of7.0 ha,3.3% of which is covered with riparian vegetation, with average slope of 19.6%. The total experimental period comprised eight years, with comparison of the results being made between data from the 7 years before the clearcutting and data obtained during the first year after the clearcutting. Rain water and streamflow samples were obtained weekly during the experimental period, and were analyzed for N, K+, Ca++, and Mg++, with the purpose of quantifying the catchment geochemical cycling. The amount of nutrients exported with the harvesting of the woody biomass was obtained from the estimates of the arboreous biomass and the nutrients content (phytomass and mineralmass, respectively). The total, above soil biomass production of theE. saligna plantation for the seven years amounted to 178.1t.ha, distributed as follows: 145.2t as wood, 14.7t as bark, 13.62t as branches and4.6t as leaves. The nutrients contents in the total biomass were: N 200.8Kg, P 52.8Kg, K 308.3Kg, Ca 796.1Kg, Mg 133.33kg, and S3.06Kg. The nutrient concentrations for the different parts of the tree, respectively, wood, bark, branches, and leaves, were as follows: N0.07,0.21,0.19,0.92 (%); P0.02,0.09,0.04,0.11 (%); K0.11,0.38,0.34,1.01 (%); Ca0.10,3.34,0.90,0.84 (%); Mg0.03,0.39,0.15,0.26 (%); S0.01,0.05,0.02, and0.13 (%). For the entire eight-year period, total inputs in precipitation, in Kg.ha-1, were as follows: N=77.6, K=32.2, Ca=46.7 and Mg=11.9. For the same period, total outputs in streamflow were: N=7.1, K=24.1, Ca=31.7 and Mg=7.4. Results are discussed in terms of maintenance of site productivity considering the exchangeable amount contained in the soil catchment, as well as the harvesting method, that is whole-tree x wood only harvesting

Biomass, nutrient and heavy metal in eucalyptus roots fertilized with different sewage sludge

The application of sewage sludge in forestry plantations has been encouraged in several countries for promoting growth of trees. However, because the sludge eventually contains heavy metals, it has been disposed frequently in landfills. This study investigated the biomass and the concentration of nutrients and heavy metals in fine roots (Ø <5 mm) of Eucalyptus grandis trees fertilized with sludges from different wastewater treatment plants (WTPs). The experimental design comprised randomized blocks with four replications and five treatments: (1) control, without fertilization, (2) mineral fertilization NPK and (3, 4 and 5) Fertilization with 15 t ha-1(dry basis) of sewage sludge from Barueri-SP, São Miguel-SP and Parque Novo Mundo-SP wastewater treatment plants. Samples of fine roots were collected at 42 months old of trees, at layer 0-20 cm of soil, using a stainless steel probe. In this stage, the fine root biomass was similar among treatments with sewage sludge and the control. However, the soil fertilization with sewage sludge from Parque Novo Mundo WTP, conditioning with lime, provided higher root biomass than mineral fertilization. In general, the soil fertilization with sewage sludge from different WTPs increased the concentration of P, Ca, Zn and Ni in the fine roots of E. grandis and reduced the Mn concentration, but don't significantly changed the concentration of the Cd, Cr and Pb

Regeneração da vegetação arbórea nativa no sub-bosque de um povoamento de Eucalyptus saligna Smith. Localizado no Estado de São Paulo

This study evaluate the native species naturally regenerating in Eucalyptus saligna stand understory. This stand is located at Itatinga Experimental Station, of the Forest Sciences Department (ESALQ/USP). The experimental area encompasses two sites separated from each other around 250 m, differing 30 m in altitude. These two sites are different mainly in land slope and soil fertility and soil hydric retention capacity. Eight permanent plots of 625 m2 in each site were randomly sampled. The woody species Individuals with height equal or bigger than 1,5 m and the Eucalyptus saligna coppicings were surveyed in each plot. A total of 107 species were Identified and 7 species were common to both sites, distributed into 72 genera and 34 families. Based upon the results It is possible to conclude that the Eucalyptus saligna trees do not preclude the natural regeneration of the native species in the stand understory, however the floristic structure of the community is also influenced by edaphic factors and vicinity of seed sources

Propriedades químicas do solo e nutrição do eucalipto em função da aplicação de lodo de esgoto

A aplicação do lodo de esgoto em plantações florestais é uma das alternativas para resolver o problema da disposição final desse resíduo. O objetivo deste trabalho foi avaliar se a aplicação de biossólido melhora a fertilidade do solo e o estado nutricional de mudas de Eucalyptus grandis. O experimento foi montado em colunas de PVC de 20 cm de diâmetro, com nove tratamentos (testemunha, adubação mineral, doses crescentes de biossólido variando de 10 a 160 t ha-1) e quatro repetições. O experimento foi realizado durante 12 meses após o plantio das mudas. O biossólido influenciou mais a acidez do que outros atributos químicos do solo. Os teores de N, P e S nas folhas correlacionaram-se com a CTC e com o teor de C orgânico do solo, tendo essas variáveis apresentado valores significativamente mais elevados nas doses de 80 e 160 t ha-1. Observou-se diminuição da matéria orgânica do solo nas doses de 10 a 40 t ha-1. O biossólido alcalino diminui a acidez do solo e melhora sua fertilidade, aumentando a disponibilidade da maioria dos nutrientes

Volume de madeira e concentração foliar de nutrientes em parcelas experimentais de Eucalyptus grandis fertilizadas com lodos de esgoto úmido e seco Wood volume and foliar concentration of nutrients in Eucalyptus grandis after wet and dry sewage sludge application

No Brasil, diversos municípios estão construindo estações de tratamento de esgoto (ETEs), e futuramente serão produzidas anualmente milhares de toneladas de lodo para as quais deverá ser dada destinação adequada. O lodo de esgoto tratado (biossólido) é o resíduo resultante do tratamento do esgoto urbano, e sua disposição final precisa ser bem planejada devido às implicações sanitárias, ambientais, econômicas e sociais. Apresenta elevado teor de matéria orgânica e de nutrientes e poderia ser utilizado como fertilizante em plantios florestais. Esta pesquisa foi realizada na Estação de Ciências Florestais de Itatinga (Universidade de São Paulo), com o objetivo de avaliar o efeito da adição de três doses (10, 20 e 30 t ha-1) dos lodos de esgoto úmido (torta) e seco (granulado), complementados com K e B e aplicados ao solo nas linhas de plantio em parcelas experimentais de Eucalyptus grandis. Dezoito meses após a implantação das mudas no campo, o volume dos troncos demonstrou aumento significativo (ao redor de 130%) no tocante ao crescimento dos eucaliptos tratados com os biossólidos úmido e seco em relação à testemunha sem aplicação de fertilizante, bem como teve resultado semelhante ao do tratamento com adubo mineral. Entretanto, não houve diferença significativa entre os tratamentos com a aplicação dos biossólidos úmido e seco. Com relação à nutrição mineral, foi observado aumento da concentração dos elementos P, Ca e Zn nas folhas com as maiores doses dos biossólidos, e verificou-se efeito inverso de Mn. As concentrações foliares de todos os nutrientes nos eucaliptos tratados com os biossólidos mantiveram-se dentro dos limites observados usualmente nas plantações comerciais, não havendo sinais de desequilíbrio nutricional.<br>In Brazil, several municipalities are building waste treatment plants and in the future thousands of tons of sewage sludge will be generated. Sewage sludge is the waste left over after wastewater treatment and its disposal needs to be well planned, considering sanitary, environmental, economic and social implications. Sewage sludge (biosolids) is high in organic content and plant nutrient and could be applied as fertilizer in forest plantations. The aim of this research, conducted at the Experimental Station of Itatinga (University of São Paulo) was to evaluate the effects of increasing doses (10, 20 and 30 tons ha-1) of wet and dry biosolids(pellets), complemented with K and B, and applied to planting rows in experimental Eucalyptus grandis plots 1.5 years after seedling plantation. Trunk volume increased significantly regarding the eucalypt trees that received wet and dry sewage sludge, compared to the control treatment (no fertilization), and a similar growth of eucalypt trees that received full mineral fertilization. Regarding mineral nutrition, a positive correlation was observed between doses of biosolids and P, Ca, and Zn concentrations in the leaves, but a negative effect for Mn and biosolid dose. The foliar concentration of all the nutrients in the biosolid-treated eucalypt trees remained within the limits observed in commercial plantations, with no signs of nutritional imbalance