Efeitos da Manipulação da Vegetação Lenhosa sobre a Produção e Compartimentalização da Fitomassa Pastável de uma Caatinga Sucessional

Abstract

RESUMO -A pesquisa foi conduzida no Centro de Assessoria e Apoio aos Trabalhadores e Instituições Não-Governamentais Alternativas (CAATINGA), no município de Ouricuri, PE, no período de 1989 a 1994 com o objetivo de comparar diferentes práticas de manipulação da vegetação lenhosa, como alternativas de manejo pastoril sustentável da caatinga, viável em nível do pequeno produtor. Parcelas de 25 x 100 m cada uma, tiveram sua vegetação lenhosa submetida aos seguintes tratamentos experimentais: desmatamento, raleamento, raleamento-rebaixamento, rebaixamento e testemunha. Os resultados indicaram que a disponibilidade total e a compartimentalização da fitomassa da parte aérea da caatinga (folhagem das lenhosas e vegetação herbácea) foram afetadas pelos métodos de manipulação e pelas flutuações anuais da precipitação pluvial. Os tratamentos de manipulação aumentaram substancialmente a participação das gramíneas na composição florística da fitomassa herbácea. O rebaixamento e o raleamento-rebaixamento são os métodos recomendados para o manejo pastoril da vegetação da caatinga para sítios ecológicos semelhantes ao estudado.Palavras-chave: árvores, desmatamento, manejo, raleamento-rebaixamento, sub-bosque Effects of the Manipulation Methods of Woody Vegetation on Production and Compartimentalization of the Grazeable Phytomass of a Successional CaatingaABSTRACT -The research was carried out at the Centro de Assessoria e Apoio aos Trabalhadores e Instituições Não-Governamentais, Alternativas (CAATINGA) in the Ouricuri county, state of Pernambuco, Brazil, in the period of 1989-1994, with the objective of comparing different practices of woody vegetation manipulation, as alternatives of sustainable pastoral management of caatinga and determining their viability to the small producers. Plots measuring 25 x 100 m had the woody vegetation submitted to the following experimental treatments: deforestation, thinning, thinning-lowering, lowering and control. The results indicated that the total availability and compartimentalization of the aerial phytomass of caatinga (woody species foliage and herbaceous vegetation) were affected by the manipulation methods of the trees and shrubs, and by the annual variations of the rainfall. The vegetation treatments substantially increased the participation of the grass species on the floristic composition of the herbaceous phytomass. The lowering and the thinning-lowering of the woody vegetation are the recommended methods for the pastoral management of caatinga to the sites similar to that of this research.

Belowground Carbon and Nitrogen on a Thinned and Un-Thinned Seasonally Dry Tropical Forest

“…The increased availability of herbaceous plants in SDFT has therefore been achieved through changes in the structure and architecture of the tree and shrub vegetation [11] [12].…”

Interactions Between the Herbaceous and Shrubby-Arboreal Components in a Semiarid Region in the Northeast of Brazil: Competition or Facilitation?

“…In some areas of caatinga, shading can reduce the size of some herbaceous populations, which may reflect on the size and diversity of the community (ARAÚJO-FILHO et al, 2002;SILVA et al, 2009;SILVA et al, 2010). In the islands, the lower density of the community in the center can be justified by shading and this reduction in density can be considered positive.…”

Analysis of Air Temperature and Humidity in the Caatinga (Semi-Arid) Area of Brazil: Contributions to the Recovery, Conservation, and Preservation of the Biome

“…The two spots were at similar altitudes (~500 meters) and approximately 400 meters apart. One has scrub vegetation and denser soils spot (1) and the other is located in a very degraded area with sparse herbaceous vegetation spot (2). Spot (1) had been the target of environmental recuperation measures for two years at the time of data collection.…”

“…The trees in the area are pruned to remove branches that cause them to lose energy during water shortages, improving their nutrient uptake capacity. The wood waste (figure 4), is piled up to form long berms or placed at the foot of trees to help maintain the humidity of the soil and improve the uptake of organic matter (ARAÚJO et al, 2002;LIRA SANTOS et al, 2007). There are also silt fences, which are built on the beds of water bodies, creeks and streams in micro-watersheds or across rills and gullies in areas with steep slopes (LIRA SANTOS et al, 2007).…”