Eduardo Kneipp Londero

Influência de diferentes períodos de controle e convivência de plantas daninhas em eucalipto

This work studied the periods of control and coexistence of weeds with eucalyptus culture. The experiment was led in Candiota, RS, in the period from January to December, 2006. The treatments consisted of different control times and coexistence of the culture, these periods were divided in two groups; one was to determine the Period Previous to the Interference (PPI) and the other to define the Total Period of Prevention of the Interference (TPFI). In the two groups the tested periods were: 00, 28, 56, 84, 112, 140, 168, 210, 252, 294 and 336 days. The young trees of eucalyptus were susceptible to weed, presenting a period previous to the interference of 56 days. In order to guarantee its largest production, the total period of prevention of the interference was 140 days and the period previous to the interference was of 56 days.

Exportação e reposição nutricional no primeiro desbaste de um povoamento de Pinus taeda L. em área de segunda rotação

This study aimed to quantify biomass, the export and nutrient replacement in trees of a first thinning Pinus taeda L. stand, in Cambara do Sul, RS state. To do so, a forest inventory was done in three plots (60 m x 60 m), where three trees were cut in each plot. Live and dead needles, live and dead branches, bark, wood (bole) and wood from tip with bark, were measured. Total biomass was 44,5 Mg ha -1 , being 62,8% of bole wood, 10,3% live branches, 8,9% bark, 10,1% live needles, 6,1% dead branches, 3,5% of wood from tip with bark and 0,5% dead needles. Total nutrients in biomass, in kg ha -1 , was: 100,5 of N; 51,1 of Ca; 46,8 of K; 18,2 of S; 14,3 of Mg; 11,7 of P; 0,599 of Mn; 0,158 of Fe; 0,435 of Zn; 0,181 of B and 0,177 of Cu. The quantity of the fertilizer to be replaced will depend on the exploration type. If the total biomass occurs, the quantity of the fertilizers to be replaced will be of 391 kg ha -1 , and if it is considered just the wood harvest this replacement will be 60% inferior, 169 kg ha -1 .

APORTE DE SERAPILHEIRA E NUTRIENTES EM UMA FLORESTA ESTACIONAL DECIDUAL NA REGIÃO CENTRAL DO RIO GRANDE DO SUL

The objective of this study was to quantify the deposition and nutrients input by litter in the fragment of Seasonal Deciduous Forest, in Itaara, Rio Grande do Sul state, Brazil. Thirty circular metal collectors were allocated in six plots. The deposited material in this structure was separated in leaves, identified by species, fine branches (diameter autumn>winter>summer. The nutrients input follow the order: N>Ca>K>Mg>S>P (macronutrients) and Fe>Mn>B>Zn>Cu (micronutrients). The higher nutrient depositions by litter was Parapiptadenia rigida , following of Ocotea pulchella and Matayba elaeagnoides.

CALIBRAÇÃO DO MODELO 3-PG PARA Eucalyptus saligna Smith NA REGIÃO DE GUAÍBA - RS

The study aimed to calibrate the model 3-PG for Eucalyptus saligna for the following the diameter variables at breast height (DBH), total height, wood volume and branch, bark and wood biomass. The study took place in the region of Guaiba, Rio Grande do Sul state, Brazil. Clonal plantations of Eucalyptus saligna in various spacings were used. Six different ages were selected along the crop cycle (2nd to 7th year). After the forest inventory was carried out, the biomass of three trees fractionated into wood, bark, branches and leaves was collected. The biomass of roots on the average tree of each plot was measured to a depth of 1 m. Physical and chemical analyses were performed in soil samples from the layers: 0 to 20 cm, 20 to 40 cm and 40 to 100 cm. Litter deposition was estimated by allocating 4 square collectors of 0.5 m². The leaf area was obtained through digital photographs and thus the specific leaf area was estimated. The physiological parameters were measured in six plots, one at each age. Climatic parameters were provided by EEA of UFRGS University, located in Eldorado do Sul, RS state. The model validation was not statistically accepted, but their estimated data can be used to estimate the studied variables, demonstrating the potential of its use although additional studies for the application of the model to this species are still needed.

QUALIDADE QUÍMICA DO SOLO COM DIFERENTES NÍVEIS DE DEGRADAÇÃO EM ÁREA DE PRESERVAÇÃO PERMANENTE

CHEMICAL QUALITY OF SOIL WITH DIFFERENT LEVELS OF DEGRADATION IN THE ENVIRONMENTAL PERMANENT PRESERVATION AREAS The objective of this study was to investigate possible effects of soil contamination from pollution by urbanization and inordinate use of the course on the shores of the Sanga Lagoao of Ouro through soil chemical variables analyzed with multivariate statistical tools. We established five sampling points in the path of urban Sanga that have different uses and management. Alterations in the characteristics of soil in accordance with the management imposed. Similarity was observed the formation of three patterns chemical characteristics: soil fertility (1), acidity (2), and the amount of MO, N and K (3) in the soil. Four factors (represented by F1, F2, F3 and F4), explained 88.34% of the total variation of the data, and the factor F1 is the greatest explanation of the SZYMCZAK, v(10), no 10, p. 2158 – 2169, OUT-DEZ 2012.

Crescimento da acácia-negra em resposta a aplicação de nitrogênio, fósforo e potássio

Em razao da escassez de informacoes sobre adubacao em acacia-negra, no presente estudo, objetivou-se avaliar o crescimento de plantas de acacia-negra em funcao de diferentes niveis de adubacao com nitrogenio, fosforo e potassio, apos seis anos da implantacao. O delineamento utilizado foi de blocos ao acaso, com distribuicao trifatorial (doses de fertilizantes). Avaliou-se a altura total (m), diâmetro a altura do peito (DAP) (cm) e volume de madeira com casca (m³ ha-1). A acacia-negra apresentou resposta positiva e significativa, de crescimento as adubacoes com N e P (interacao) e ausencia de resposta ao K. Para a obtencao do maximo crescimento da acacia-negra, para a condicao edafoclimatica estudada, deve-se utilizar a dose maxima de nitrogenio (40,0 kg ha-1 de N) e 78,9 kg ha-1 de fosforo, nao sendo necessaria a adicao de potassio via fertilizantes.