B8q:Climate Change and the Forest Environment

Forests store carbon in biomass and soil and when harvested, part of the carbon is stored in wood products. These products may substitute functionally similar products made from more emission-intensive materials. We reviewed the existing literature to update and improve the understanding of the climate effects of substituting wood products.

We conducted a systematic review covering over 50 studies and yielding over 400 substitution factors. Most studies focused on North America and the Nordic countries in Europe with only few studies from other regions. Most of the substitution factors related to construction materials, and substantially fewer substitution factors were available for other product types (furniture, packaging, and textiles) and even fewer for paper and chemicals. Overall, the reviewed studies suggest an average substitution effect of 1.2 kg C / kg C, which means that per kilogram of wood products that substitute non-wood products, there occurs an average emission reduction of 2.2 kg CO₂. However, the substitution effects vary significantly, depending on the wood and non-wood products considered and the assumptions applied to estimate emissions.

We conclude that the use of wood products is generally associated with lower fossil and process-based emissions, compared to non-wood products. However, substitution factors as such are not sufficient to guide policy-making. The fundamental aim should be to minimize emissions, through forest management activities, long-term storage of C in wood products and substituting emission-intensive materials. Resource-efficiency and minimizing material waste for both wood and non-wood based products should be simultaneous policy targets for climate change mitigation.

Araucaria angustifolia (Bert.) O.  Kuntze (Araucariaceae) is a subtropical rain forest tree that has social and economic importance due its wood quality and eatable seeds. To increase the knowledge about its genetic variability and its probable relationship with the physical environment, we are performing the edaphic, landscape and climatic characterization of natural populations occurring in a wide region including the latitudinal limits of Brazilian territory. From October 2015 to August 2016, we selected A. angustifolia trees from natural populations representing four Brazilian States. In those places, individuals were sampled, georeferenced (latitude, longitude, altitude), the relief was characterized and the soil were classified according to Brazilian Soil Classification System. Descriptive and cluster analysis, with field information, allowed the preliminary evaluation of these environments. As for edaphic aspect, the main classes of soil observed are Latosols (Oxisols), Cambisols (Inceptsols), Neosols (Entisols) and Nitosols (Alfisols). The southernmost sampled populations of Brazil (Pelotas region, Rio Grande do Sul State) are distinct from others by their lower altitude, around two hundred and ninety meters, and prevalence of shallow soil. Environments with the greatest contrast to this condition were located in the south of Minas Gerais State, with populations established over two thousand meters of altitude. Populations surviving in stressful environments are very important for conservation purpose, as result of local adaptation driving by extreme conditions. The attributes analyzed compose an information plan that will help to project the present and future occupation of these populations based on the IPCC scenarios.

In order to quantify productivity and forage quality in silvopastoral systems the species Albizia niopoides, Cordia alba, Gliricidia sepium, Guazuma ulmifolia, Leucaena leucocephala, Moringa oleífera, Senna spectabilis y Tithonia diversifolia were evaluated in El Espinal (C.I Nataima, Agrosavia). The growth form of the tree plant was modified by pruning at 0,8 m (height) and time intervals between harvests (30-45-60 days). In a randomized complete block design, plots with 270 individual plants per species were sown in three rows, and water or nutrients were not added. The species T. diversifolia, C. alba and S. spectabilis had the higher forage averages for 30 days harvest period with 145, 139 and 160g^-1DM respectively, however these species presented had high mortality under this harvest’s interval. On 45 days harvest period, the survival and the forage production improved for the species. The highest production respectively was presented by C. alba 450g^-1 DM, S. spectabilis 395g^-1DM and T. diversifolia 330g^-1DM. On 60 days harvest period the highest production was for S. spectabilis 643g^-1DM and C. alba 612g^-1DM. At this interval, some branches were mainly a woody resource and sometimes unattractive for ruminant’s consumption. On the other hand, L. luecocephala y M. oleífera presented the lowest forage biomass production per plant <160 g^-1DM and the higher protein content. This evaluation allows to recommend managing these tree species in silvopastoral systems at 0,8 m and harvest intervals of 45 days. Under these recommendations these tree species decrease mortality and improve adaptation to climate seasonality during the establishment of silvopastoral systems in dry zones.

Euterpe edulis is considered a key species in the Atlantic Forest and is currently classified as vulnerable at a Brazilian list of threatened species, due to illegal extraction. In order to provide information for future projects of conservation, the present study characterized E. edulis reproductive phenology in four altitudes (30, 100, 200 and 400 m) in Salto Morato Natural Reserve – Guaraqueçaba/PR. In each altitude, five individuals were monthly monitored from March/2017 to February/2018. The intensity of phenophases was registered following the methodology proposed by Fournier. Flowering started at the lowest altitude (in September) and lasted for four months with a peak in November. At 200 m, flowering was present only in November. Immature fruits were present in the lowest altitude from December until February (with a peak in January) and, at 200 m, it only occurred in March. Green fruits were observed in three altitudes: at 30 m, it started in February and lasted for three months; at 100 m, it started with one month of delay (in March) and lasted for four months; at 200 m, this phenophase initiated with two months of delay (in April) and lasted also for three months. Mature fruits also presented differences as they initiated at different altitudes: it started in February at 30 m; in June at 100 m and in May at 200 m. There are differences in reproductive phenology of E. edulis throughout the gradient, which can be explained by differences in microclimate.

The diversities of plants and ecosystems are sensitive to climate and soils variations, however climate is fast deteriorating at large scale. Therefore, botanical and ecological studies are necessary in climate transition area for phytodiversity monitoring, then to prevent species extinction. In this particular case, we carefully chosen Comoé-Léraba protected area.

After inventories, based on the recent plants species listed in Burkina Faso, this protected area provides in proportion 26.12%. The importance of Guineo-Congolian species (113) proved that the Comoé-Léraba flora belongs to the Sudano-Guinean transition sector. It also accounts the highest number of exclusive species (118) in the country. Furthermore, in related to each ecosystem, 11 plants communities’ have been clearly defined, according the phytosociological statements (DCA). Among these communities four news taxa were determined based on previous studies in the same phytogeographical zones. Then their direct ordination (CCA) with soil’s (physical and chemical) parameters, shows that plants communities’ distribution is governed mainly by water regulation on the ground and also its texture. 

Comoé-Léraba is located at the most humid zone of the country, but due to climate warming, exclusive species and rare plants communities which have been discovered, could move away from the country. Consequently, this protected area required closely attention.

Forests act as important components of ecosystems in mountainous areas, where forest management should balance environmental protection and socio-economic development of local communities. Being a part of Eastern European Mid-latitude ecotone, mountain forests of the Ukrainian Carpathians represent a resource-rich forest management hotspot in a developing country. Given the low efficiency of energy use in Ukraine and growing energy demands, forests can and should play an important role as a renewable energy source in the near and far-off prospects.

Theoretical and methodological background for quantitative assessment of energy potential of woody biomass in mountain forests shall be based on provisions of sustainable forest management and reflect the balance of the three structural components of sustainable development – environmental safety, economic development, and social interests. Considering certain environmental, economic and social constraints on energy use of wood biomass in mountain forests, we propose to distinguish five types of energy potential: theoretically possible, technically accessible, environmentally safe, economically profitable and socially conditioned.

Having implemented the abovementioned principles and approaches, we have assessed energy potentials of wood biomass for Carpathian Mountains region: theoretically possible – 49.4 PJ; technically accessible – 35.2 PJ; environmentally safe ­– 25.4 PJ; economically profitable – 22.9 PJ and socially conditioned ­– 20.3 PJ. The last-mentioned type of energy potential expressed in volume of timber means that over 2.2 million cubic meters of wood could be used for bioenergy purposes. The proposed research results can serve as a component of an information system aimed at implementation of adaptive forest management in the Carpathian region.

The dry tropical region of Colombia has periods of 145 to 220 days / year without rainfall. In addition, the average temperature of 29 °C, relative humidity between 56 and 65%, poorly distributed precipitation, however, fall 1272 to 1400 mm / year and evaporates more than the precipitation received. These variables would be directing the behavior of the plants towards different forms of response, since a plant hardly maintains its leaf tissues alive, when periods of drought are long. Using mixed linear models with varcomp statistical function in two key functional features, specific leaf area (SLA) y Wood density (WD) of species (Cordia alba y Guazuma ulmifolia) found in paddocks at three ecological scales (species, tree and show). Interspecific variability of traits (50.34-79.08%) e intraspecífic Árbol (28.18-17%) and simple (41% para SLA) respectively. Comparisons for SLA and WD, shows that features trees in paddocks with significant differences (P-valor=0,0001. R²=0,77). SLA values in C. alba varies between (17,19+0,7 to 17,49+0,57mm²mg^-1) y G. ulmifolia (12,71+0,57 to 13,83+0,57mm²mg^-1), showing stability. The WD for C. alba varía between (0,45+0,02 to 0,53+0,01 mg.mm^-3) y G. ulmifolia entre (0,44+0,02 to 0,53+0,01 mg.mm^-3), being this variable, indicator of adaptation of species to water stress. The high interspecific variability (50-79%), it follows patterns reached in other studies, while intraspecific variability (tree-show), present important varability. Results indicate that intraspecific variability (tree-show) are dominated by interspecific variation (species), but that there is an intra-specific variability in trees and foliar structures that can not be ignored.

The relationship between climate and the agricultural system is well known and described in the literature. However, with the increase in the frequency of occurrence of extreme climatic events - such as prolonged and successive droughts, torrential rains, high daytime, and nighttime temperatures - the agricultural production system has become even more unstable. Given the humanity dependence on increasing agricultural production, here we hypothesized that agriculture is moving to areas less suitable to grow crops and even the consolidated fields could become less suitable in the future. We also tested if different landscape compositions would change the relationship between crop productivity and the weather. Especifically, we 1) quantified the relationship between climate and first and second crops across the Brazilian agricultural frontier; 2) characterized climatically the areas where agriculture is expanding to in recent years; 3) quantified agricultural de-intensification, 4) compared the past and future climatic conditions of agricultural fields;  and 5) quantified the relationship between forest amount and crop yield productivity of the second crop. In hotter and drier years, production, productivity, and planted area were lower in the second crop. Agricultural climate space has already changed. At the same time, agriculture expanded into hotter regions, although into places with more precipitation during the wet season. In regions with lower forest cover, the forest plays a positive role in the productivity of the first and second harvests. The crop production stability in the Brazilian agricultural frontier may depend on the standing forest.