Resumo em Inglês:

Abstract Lignin is related to mechanical support, fluidity of water transport by xylem and resistance to pest and pathogen infections. This research measured the concentration of lignin and its correlation with field performance of Cordia trichotoma (Vell.) Arrab. ex Steud seedlings submitted to hardening. Seedlings were treated with 20 stem bending for 4 or 8 weeks, application of 50 μmol L-1 of methyl jasmonate for 4 or 8 weeks and a control treatment. In the nursery after treatments, six seedlings were randomly selected for determination of root electrolytes and lignin content from stem and root tissues. Application of jasmonates or stem bending in the nursery promoted an increase in stem lignin concentration but did not induce a greater lignification of root systems. After 450 days of planting, saplings height and diameter increments and percentage survival were calculated along shoot lignin content. Saplings showed no differences in shoot lignin from nursery hardening.

Resumo em Inglês:

Abstract This study investigated the electrical resistivity of 105 timber species from the Peruvian tropical forest; with a focus on promoting sustainable use by considering the wood’s equilibrium moisture content (EMC). Employing a non-destructive method, it correlated the wood’s physical properties with its electrical resistivity, uncovering an inverse exponential relationship between resistivity and EMC, with resistivity values ranging from 0.0244 x 109 Ωm to 26.0104 x 109 Ωm across different cutting directions (longitudinal, tangential, and radial). These findings allowed for the classification of the woods into five groups based on their moisture balance and electrical resistivity, from very high to very low. This classification aids in identifying the appropriate and sustainable use of these timber species in various applications, highlighting the study’s contribution to sustainable forest management.

Resumo em Inglês:

Abstract Sustainable forest management (SFM) is a rational exploitation practice adopted in the Caatinga. This study aimed to evaluate the stock and the nutritional and organic composition of litter in Caatinga subjected to different forest management practices: shallow cutting (SC), selective thinning by minimum diameter (STMD), and selective thinning by species (STS), and using unmanaged Caatinga (control) as a reference, in dry and rainy seasons. There were a significant increase in total litter in STS and a decrease in stocks of STMD, shallow cutting and unmanaged forest. Forest management reduced leaves in the accumulated litter in both seasons and increased contribution from branches. The STS management promoted maintenance of the stock and nutritional and organic quality of the litter, bringing it closer to the condition of unmanaged natural forest in both climatic seasons. So, should be encouraged for a more sustainable management of the Brazilian phyto-physiognomy Caatinga.