No abstract

We performed a forest growth dynamics study in Acre State, Brazilian southwestern Amazon, where a 20 ha area was logged in 1992. The study was based permanent sample plots (1 ha) established in the logged area and in an unlogged forest immediately after logging operations finished. Forest dynamics parameters were assessed in terms of aboveground dried biomass (AGB). During the study period, three extreme climate events triggered a high impact on both logged and unlogged areas, producing AGB losses greater than those estimated for logging. Twenty years after logging, ingrowth and mortality rates were similar to those expected in an undisturbed forest, and AGB recovery was significantly faster in the logged areas. Forest management, when properly applied, can promote faster forest AGB recovery. We suggest that forest management could be considered as an alternative to adapt to extreme climate events, by promoting controlled disturbances, which should minimize tree mortality and biomass loss.

This study includes an economic analysis of the dynamics and prognosis of the forest structure of an area under sustainable forest management in the Amazon, in the primary production of tropical roundwood. It analyzes measurements taken between 2001 and 2011 and carries out forest forecasting for the period from 2001 to 2021 with the application of the Markov Matrix Chain. The variables measured by the probability matrix were transformed into equivalent annual rates and compared over the same period to the Brazilian macroeconomic indicators of gross domestic product (GDP) and the real interest rate of primary roundwood production (TJLP). The valuation of tree density utilized a series of average prices of world imports and exports of roundwood. Between 2001 and 2011, the parameters of the forest dynamics without valuation were similar to the TJLP (1.4% per year) and, when valued, the rates were close to the GDP of 3.5% per year. The forecast from 2001 to 2021 indicates that unrated economic groups behave in a similar way to the TJLP of 1% per annum and to the GDP of 2.2% per year, except the recovery category, which has a negative rate of 1.9% per year. The monitoring of tropical forests allows the achievement of economic indexes capable of assessing the anthropic and natural impacts in short periods of analysis and projecting them over time on natural capital.