Navegando por Assunto "Reflorestamento - Pará"

Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Desenvolvimento inicial de teca (tectona grandis) em resposta à fertilização com NPK em diferentes condições edafoclimáticas no estado do Pará
(Universidade Federal do Pará, 2015-08-31) FERREIRA, Adélia Ribeiro; BRIENZA JÚNIOR, Silvio; lattes.cnpq.br/1750852376922258
The areas headed for reforestation generally have law fertility, and then they demand a balanced fertilizing to provide levels of compatible nutrients according to each specie. Therefore it is necessary the property value of reference more accurate to the fertilization recommendation of forest species. The studies published about teak fertilization under field conditional are so scare, this paper aims to evaluate the influence fertilization with N, P and K of climatic factors in the growth of the teak, in different soil conditions of Para state. The fertilization test constitutes of a factory experiment with dose of N and K applied on teak at the Vigia and Santa Maria das Barreiras cities, in experimental design in randomized blocks with three repetitions, in factorial arrangement 4 x 2 m, it is four doses of nitrogen and two of potassium, totaling eight treatments and 24 experimental plots. And other factorial experiment with doses of P and N applied in teak at the Vigia and Santa Maria de Barreiras cities, with design in randomized blocks and three repetitions in factorial arrangements 4 x 2 m, it is four doses of phosphor and two doses of nitrogen, totaling eight treatments and 24 experimental plots. The growth in H and DAP of teak submitted to doses of N and K at Vigia and Santa Maria das Barreitas cities, to 30 months of age, It was not significantly influenced by N x K factor, it is not happened the growth on these two variable owing to elevation of N x K doses applied in soil. At the soil conditions studied at Vigia city, the maximum growth in H was achieved with doses of 80 g of N and 138,5 g of P plant- 1, and the maximum growth in DAP was achieved with doses of 80g of N and 206 g of P plant-1, while the soil conditions studied at Santa Maria das Barreiras city, the maximum growth in H was achieved with doses of 40 g of N and 140,62 g of P plant-1, and the maximum growth in DAP was achieved with doses of 40 g of N and 161,25 g of P plant-1. The IPDAP showed a relationship between the precipitation seasonality with the high values of IPDAP happened on the rainy period and lower values happened on the less rainy period.
Acesso aberto (Open Access)
Dinâmica de serapilheira e produção de raízes finas em plantios de Paricá (Schizolobium Parahyba Var. Amazonicum) e floresta sucessional em Aurora do Pará, Amazônia Oriental
(Universidade Federal do Pará, 2009-06-29) SILVA, Antonio Kledson Leal; VASCONCELOS, Steel Silva; http://lattes.cnpq.br/0719395243841543
The establishment of silviculturals and agroforestry systems with the paricá (Schizolobium parahyba var. amazonicum) expanded in the state of Pará, brazil, usually as alternative to reforestation of degraded areas (abandoned pasture). However lacking basic studies on the cycling of organic matter to understand the potencial of paricá to recover degrades areas. Set up an experiment on the farm Tramontina, Aurora do Pará, to evaluate process connected with cycling of organic matter, how the litter production (litterfall), litter stock, production of fine root during 12 months (October 2007 and September 2008), in treatments with plantations of paricá with five years, in the following arrangement: paricá single (PS), consortium paricá + freijó (Cordia goeldiana) (PF), Agroforestry systems with paricá, freijó and curauá (Ananas comusus var. erectifolius) (PFC). This treatments with paricá was compared with an area of reference (successional forest ecosystem with 25 years of age) (SUC). The treatments of paricá presented annual litter production under SUC (8,79 ± 0,08 Mg ha-1 yr-1), no significant difference between treatments PS (6,05 ± 0,15 Mg ha-1), PF (6,08 ± 0,13 Mg ha-1 yr-1) and PFC (6,63 ± 0,13 Mg ha-1 yr-1). The monthly production of litter was significativety major in dry season than wet season. The largest stock of litter has been identified in treatments with paricá PS (7,7 ± 1,0 Mg ha-1) and PF (7.4 ± 0,1 Mg ha-1), while the SUC presented an stock of 5.9 ± 1,3 Mg ha-1. This results is related to the lower rate of decomposition found in treatments with paricá. The production of total fine roots (live + dead) was significativelly major in the treatments PS (380,3 ± 20,6 g m-²), PF (343,0 ± 18,4 g m-²) and PFC (265,5 ± 9,9 g m-²) than SUC (107,2 ± 2,7 g m-²), the variation of fine roots production in the period of study is associate with a seasonality of pluviometric precipitation; the fine roots production decreases during the period of increased precipitation and increases with the arrival of the dry period. Treatments with paricá showed good ability to provide organic material above and below the ground. More specifically, the paricá presented high production and storage of litter on soil, which are desirable attributes in systems for recovery of degraded areas.