Resumo em Inglês:

ABSTRACT Increased production of agro-industrial waste is a global concern, requiring proper disposal. In this sense, they can represent alternative sources for substrate production, adding value to the materials and reducing the cost of seedlings in the nursery. However, their proportions in the mixture should be adequate for better use of water and nutrients, ensuring better seedling quality. The objective of this study was to identify the potential of rice husk and peach kernel residue, as a secondary substrate component, for the production of Eucalyptus grandis seedlings. The carbonated (CRH), hydrolyzed (HRH) rice husk and crushed peach kernel (CPK) were added at 0, 10, 20 and 30% to an organic substrate. The results were submitted to analysis of variance and correlation analysis between the variables of the substrates and the morphological and physiological attributes. The results indicated that the HRH and CPK can add value to the agro-industrial residue when mixed to the organic compound in proportions of 20 and 10%, respectively, being adequate and compatible with the use of CRH in the proportion of up to 30%. Eucalyptus grandis seedlings, after 90 days of cultivation, presented quality to be hardened and dispatched when grown on organic compound substrates with up to 30% CRH, 20% HRH and 10% CPK.

Resumo em Inglês:

ABSTRACT Brazil is a mega diverse country, but as consequence of habitat degradation several plant species are threatened. Quillaja brasiliensis is a rare and threatened tree species of the temperate forests of South America. We investigated protocols for germination, seedling growth and transplantation. We discuss some ecological matters that could affect the species’ establishment. We evaluated germination under a range of storage periods, temperature and light conditions, the effects of transplantation and the development of seedlings under two sowing methods. We found that seeds germinated rapidly and have a high germination rate. Temperature infl uenced germination vigour, and photoperiod infl uenced synchrony. There was increased and faster germination under controlled culture conditions. The high germination rate and rapid growth qualify Q. brasiliensis as a potential species for restoring degraded areas and enrichment programmes.

Resumo em Inglês:

ABSTRACT The use of a forest seedling bank has been recommended as an alternative to increase species richness in forest nurseries, as well as to produce seedlings of species that are diffi cult to propagate, especially those that belong to the late secondary and climax successional groups, which are not as commercially available. However, little is known about the impact of this method on forest dynamics. Thus, the present study aimed to examine the resilience and dynamics of a seedling bank in a remnant of a subtropical seasonal forest belonging to the Atlantic Forest Biome when subjected to different intensities of seedling removal. The experiment was conducted in a random block design in a factorial scheme (5 × 4), with treatments composed of fi ve intensities of removal of individuals from the seedling bank and the four seasons. The treatments were distributed into 18 blocks and the experimental units were composed of 1 m × 2.5 m plots. The resilience of the seedling community was assessed by examining effects of the fi ve removal intensities. The dynamics between the evaluation periods within each treatment were verifi ed by comparing the number of species and seedlings present before the treatments with those in the other evaluation periods. After one year, we found that tree-shrub vegetation had a partial capacity for restoration after withdrawal of individuals from the seedling bank. Our results show that the impact on the regeneration community can absorb the effects of up to 25% seedling removal. The technique of seedling transplantation may be recommended for species that have abundant regeneration, such as Actinostemon concolor, Eugenia rostrifolia, Trichilia claussenii and Nectandra megapotamica.

Resumo em Inglês:

ABSTRACT Copaiba trees, of the genus Copaifera (Fabaceae), produce an oleoresin that has pharmacological applications. The yield from the trees is very variable, and factors affecting production are still unknown. We evaluated the yield of oleoresin from Copaifera spp. in the Cerrado- Amazonia ecotone, as well as its relationship with the growth and age of trees. We sampled 30 Copaifera trees by extracting oleoresin for 24 h with a metal borer. Increment cores were collected from 15 trees to determine their age by counting growth rings and to calculate the mean annual increment of the diameter at breast height. The cylinders were sanded and the number of growth rings was counting with a magnifying glass (10x). The ages of trees from which increment cores were not collected were estimated by simple regression analysis. The proportions of productive and non-productive trees were recorded. The best adjusted model for age estimation showed R²adjust. = 0.616 and Syx% = 4.42. The average productivity of oleoresin was 0.124 L per day, and 30% of the trees were productive. The proportion of productive trees increased with increasing diameter at breast height and age, but after a point, increasing diameter was associated with reduced productivity. The mean annual increment had an inverse relationship with diameter for the productivity of oleoresin. The results suggest that other factors could be triggering and controling the oleoresin production and not only the age.

Resumo em Inglês:

ABSTRACT Khaya ivorensis stands out because of the quality of the wood and high economic value. Its propagation has been carried out by seeds, an obstacle in the production in large scale seedlings, since the seeds present high value and they result in heterogenous stands. The vegetative propagation is an alternative to overcome these problems. The aim of this work was to verify the feasibility of mini-cutting for african mahogany, evaluating the pro- ductivity of the mini-stumps, the rooting of mini-cuttings using different concentrations of IBA and the clonal seedlings quality. The mini-stumps were produced from seeds in tubes, pruned at 8 cm, at 60 days. At 100 days after apical pruning, the fi rst sprouts col- lection was performed, and the mini-cuttings were submitted to concentrations of IBA (0; 2,000; 4,000 and 6,000 mg.L-1) for rooting evaluation. The seedlings were transplanted to clonal mini-garden, in which four collections of mini-cuttings were performed. Clonal seedlings quality was evaluated at 120 days after staking. The species showed tolerance to apical pruning and successive collections of mini-cuttings, with 96.4% survival and more than 92% of the mini-stumps producing mini-cuttings. It was observed 100% survival and rooting of mini-cuttings. There was no effect of the IBA on the rooting percent- age of the mini-cuttings, however, the higher concentration of IBA increase the thinner root production. The fi nal clonal seedling quality has similar growth for all treatments.

Resumo em Inglês:

ABSTRACT Land use changes are related to urbanization, economics and technology, influencing the management of natural resources and the ecosystem processes. The present study evaluated the behavior of land use changes in the period of 2007 and 2016, and identified the influence of these changes on the Atlantic Forest vegetation and the expected consequences for a future scenario in the short (2020) and medium term (2025). The study was developed in the Una river basin, located in southeastern Brazil. Land use mapping was performed using Landsat 5 and Sentinel-2A satellite imagery, with visual interpretation techniques. The assessment of land use changes and ecological losses was modeled in the Land Change Modeler and the gains and losses for each category and their future scenarios were identified. The calculations of landscape metrics were performed with the V-LATE extension for ArcGIS. The Anthropogenic Exposure Indicator was applied to evaluate the exposure of fragments. The comparative between land uses showed an increase of 484.33 ha of anthropogenic areas and a decrease of 484.14 ha of vegetation. The greater conversion of forests to other uses was related to agriculture. The fragments are under intense edge effect and 13.70% are under high anthropogenic exposure. By 2016, a loss of 484 ha of Atlantic Forest was identified, being expected a loss of 694.11 ha by 2020 and of 934.10 ha by 2025.

Resumo em Inglês:

ABSTRACT Relationships between tree size and density are important to define the growing space utilization in a stand. Although a universal slope for the maximum size-density relationships (MSDRs) has been previously suggested, recent research have highlighted that these relationships are species-specific. Oriental beech (Fagus orientalis Lipsky), Trojan fir (Abies nordmanniana subsp.equi-trojani), black pine (Pinus nigra Arnold) and Scots pine (Pinus sylvestris L.) represent different crown architecture, growth rate and shade tolerance; however, MSDRs have not been developed for these tree species in northern Turkey. In this study, average maximum density (DAM) slopes for these tree species were determined. Results suggested that MSDRs varied among the species, and that their slope differed from the universal slope of -1.605. The MSDRs described in this study are useful for managing stand density in natural stands of the species analyzed.

Resumo em Inglês:

ABSTRACT In this work, we studied the infl uence on the mechanical and physical properties of paper made of pulp from recycled cardboard and paper (printing/writing and newsprint) by adding different percentages of nanofi brillated cellulose. For each type of recycled pulp, we formed paper with incorporation of 0, 5 and 10 wt% nanofi brillated cellulose. The results showed that addition of nanofi brillated cellulose reduced the paper thickness and increased the density values. Papers with nanofi brillated cellulose presented resistance properties with values statistically superior to the treatments without addition. Addition of 10 % provided the best results, with improvement of tensile, burst and tear resistance of 97, 133 and 104 %, respectively, in comparison to normal papers. The paper produced with the recycled newspaper pulp had lower increase in mechanical properties from the nanofi brillated cellulose in relation to the papers with recycled pulp from cardboard and printing and writing paper. The considerable improvement in the mechanical properties is related to the increase of hydrogen bonds between the fi bers and nanofi bers, forming a dense network, resulting in greater surface area of nanofi brillated cellulose.

Resumo em Inglês:

ABSTRACT The entry of trees into a community is an irregular process often constrained by species interactions and regeneration niche. We experimentally examined the effect of light intensity (high, medium and low), substrate type (mineral and cover with litter) and presence of Chusquea culeou (Poaceae), on the performance of regeneration of Nothofagus dombeyi, N. obliqua and N. alpina (Nothofagaceae). These species constitute the natural forest within the lake Lácar watershed (40° 08´ W, 71° 30´ S). Populations of C. culeou, an abundant understorey component that restrict tree regeneration, experimented in 2001 a gregarious fl owering and subsequent mortality comprising 200,000 ha and the development of an abundant seedlings cohort. During tests, Nothofagus species exhibited a very low germination (< 2.2%) positively correlated with seed weight. Plant emergence and size was larger and mortality smaller under high irradiation, probably as an adaptation to colonize open areas. Reduced germination of seeds on organic substrate was ascribed to the role of litter as a physical barrier. Nothofagus exhibited 76% of increased mortality under the presence of C. culeou, whose germination was very abundant (93% in laboratory) and occurred preferably with high irradiance and litter. However, C. culeou also showed a good response with lower light levels. After senescence, C. culeou would form an abundant and fast-growing cohort that probably limits Nothofagus ability to establish, given increased mortality and litter accumulation. These results contribute to a better understanding of succession, which is crucial for implementing a sound management of this valuable ecosystem.