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Biomass extraction in native forests can induce changes in the functioning of these ecosystems; these changes are poorly studied, and this represents a knowledge gap. In this work, we evaluated the response of plant litter production and decomposition to increasing intensities of strip cutting in native scrublands. We set an experiment replicated in three sites: hillside with southern exposure (FS), hillside with northern exposure (FN) and valley bottom (R), with four intensities of strip cutting (0, 30, 50, and 70% of the area). To evaluate decomposition, we used bags filled with ñire leaves (Nothofagus antarctica), and for the production of litter, plastic mesh collectors. In addition, vegetation height and cover were measured. In the three sites, we observed the same temporal pattern of decomposition, with a marked decrease in organic matter during the coldest period of the year. The effects of cutting intensity were strongly influenced by the site: at FS, litter production increased, but there was no effect on decomposition; in contrast, at FN and R, production decreased and a curvilinear pattern was observed, with highest decomposition at intermediate harvest intensity. Aerial cover was positively correlated with production, and this, in turn, negatively correlated with decomposition. Our results suggest that in scrublands with high vegetation cover, strip cutting could promote litter production without affecting decomposition. In contrast, less productive sites with lower vegetation cover would be more sensitive to forestry interventions. [ABSTRACT FROM AUTHOR]

Dasometry is the branch of forest sciences that uses statistical methods to find solutions to problems related to the existence, growth and management of forests. When the Forest Law N° 29763 appears, decreed by the Peruvian State from the year 2011, the traceability or tracing of the trunk or the log coming from the forest began. At this stage, there is a noticeable difference between the census volume (standing tree) and the actual volume (tree in the storage yard), which led to penalties by the justice system. The objective of this article is to quantify this anomaly to demonstrate to forestry actors in both the private and public sectors the error that translates into costs. For this purpose, a random sample consisting of 196 trees declared by the Forestry Concessionaire Pucallpa Export SRL of Ucayali Peru and controlled by the forestry authority was taken. Dasometric calculation formulas were proposed both to find the census volume and the actual volume. The difference between one and the other was on average 2.92 m3 of wood per tree, therefore it is indicated that the morphic factor of 0.65 induces an unacceptable error so it is recommended to omit its application. To statistically justify the validity of the results, the normality of the data is checked and the t Student test is applied for paired samples, in order to verify that the difference between the two volumes is statistically significant. [ABSTRACT FROM AUTHOR]

In any production process, if it is to be sustainable, the available natural, material and human resources must be used appropriately. The logistics of usage determines the effectiveness of the process and the achievement of the desired results. The objective of this study is to analyze the management of forestry production in terms of the productive chain, since its beginning in plantations or natural forests, to the marketing and business processes of forestry companies, going through different logistically structured and planned processes, related to the efficiency of sustainable forest management. In order to do so, theoretical methods of bibliographic search of the subject were used, supported by the productive chain model of a company in terms of value and results of research carried out. An alternative for management is presented, which can be applied in any forestry company. [ABSTRACT FROM AUTHOR]

Site index models allow for the characterization of forest site productivity and the development of management strategies to achieve objectives of production and conservation of forest resources. The goal of this study was to fit and validate growth models of dominant height and site index for Pinus oaxacana Mirov. The database was derived from 4 inventories in 44 permanent plots and 58 temporary plots, established in even-aged stands located in Ixtlán de Juárez, Oaxaca, Mexico. The data were randomly partitioned into subsets of 50 %, 60 %, 70 %, and 80 % for the model adjustments and the remaining data for each subset were used for cross-validation. The models fitted were Korf, Hossfeld IV and Chapman-Richards, in their expressions ADA (algebraic difference approach) and GADA (generalized algebraic difference approach), using the nested iterative method under the non-linear least squares technique. The models that presented the best statistics for fit and validation were: in ADA, anarmorphic Korf b0 (70 %) and polymorphic Korf b1 (80 %); in GADA, Chapman-Richards (70 %) and Korf (80 %). The Chapman-Richards GADA model presented the most suitable graphical behavior and was selected to classify the forest site productivity. The dominant height and site index model applied to quantify the productive potential of P. oaxacana stands constitutes a valuable tool for the sustainable management of this species in the forests of Oaxaca, Mexico. [ABSTRACT FROM AUTHOR]

The dimensions and morphological characteristics of a tree canopy are indicators of photosynthetic capacity and are influenced by competition. Morphometric indices (MI) and correlations between dasometric variables can be used in forest management. The objectives of this study were to calculate and correlate some MI, and to model the proportional crown relationship (pc %) as a function of the normal diameter (dn), using mixed effects models (MEM) in forest plantations of Pinus pseudostrobus and P. montezumae. 11 indices and morphometric values were estimated using information regarding dn, crown projection diameter, clean stem height and total height (A). In addition, a MEM was produced using the classification variables of altitude, exposure and slope, in order to estimate the pc %. The slenderness index (A/dn) and the crown area ratio were 0.65 m cm-1 and 31.19 m2 for P. pseudostrobus, and 0.55 m cm-1 and 21.85 m2 in P. montezumae, while the dimension of the crown diameter was 25 and 31 times the dn for these two species. The best conditions for development of P. pseudotrobus occurred between the elevation intervals of 2,750 - 2,950 m a.s.l., while for P. montezumae the west and southwest exposures showed higher values. MI and MEM adjustment offer a valuable tool to calculate essential parameters of forest management and establishment of forest plantations for these two species. [ABSTRACT FROM AUTHOR]

Forest use in the Sierra Norte de Oaxaca, Mexico, has been threatened by the damage of a defoliator called the sawfly (Zadiprion spp.). The current magnitude of damage by this species is unknown, as are the biological and ecological aspects that determine its distribution. The aim of this work was to estimate the distribution and potential area of impact of Zadiprion spp. in the Sierra Norte de Oaxaca and the edaphoclimatic variables that favor its development in the region. Soil samples and specimens of the insect were collected to analyze in the laboratory. Ecological niche models were generated with MaxEnt (ver. 3.3.3), using records of the presence of the species and 19 bioclimatic variables. Reliability was evaluated using the area under the curve and a principal component analysis was carried out to identify variables. The optimal values of edaphological variables were calculated using the Kernel density index and the similarity between sites using the Gower metric. The niche models had values greater than 0.90. The most important edaphological variables impacting presence of the pest were organic matter, texture, density, infiltration, pH and moisture content. The development of adequate strategies to control the sawfly is necessary, as the pest can affect a considerable area of forest destined for forest management in a short amount of time. [ABSTRACT FROM AUTHOR]

Since 2018, the Ministry of the Environment and Sustainable Development, the FAO, and the European Union have been supporting the implementation of eight pilots involving community natural forest management. To this effect, a characterization of the wood value chain of each forest area was performed along with the compilation of their wood harvesting costs, in order to identify bottlenecks and areas for improvement, as well as to move towards the formalization of initiatives and their sustainability. This article analyzes the costs and the harvesting and market conditions in four forest areas, and it identifies the main barriers that influence the model's sustainability. The results indicate that said barriers are specific to each area and, although there are common factors among areas, they should not be generalized for a national model. These findings suggest the need for specific actions in each cluster, which are presented as recommendations. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the main preferred woods for the furniture manufacture in the provinces of Pinar del Rio and Artemisa. The method used to measure the preferences of the specialists was the so-called Hierarchical Analysis Process through the application of a survey to 350 individuals related to the consumption of wooden articles. The results obtained allowed us to define that the most preferred woods for the production of furniture are Swietenia mahagoni (L.) Jacq., Cedrela odorata L., Cordia gerascanthus (L.) Moldenke, Hibiscus elatus L. y Tectona grandis Sw. From the application of the hierarchical analysis of the species selection process, it is stated that the most accepted species is Swietenia mahagoni, presenting an acceptance range of 100 %. Respondents also state that the attributes associated with quality aspects have a great impact on the preference of the product over the designs, when the furniture is made of solid wood. Based on the forest management project of the Costa Sur (Artemisa), Pinar del Río and Macurije (Pinar del Rio) agroforestry companies, it was defined that Pinus caribaea var caribaea, Eucalyptus saligna, Samanea saman, Gmelina arborea y Acacia mangium have the potential to be used in the furniture industry based on their volumes and permanence in the forest heritage of the companies studied. [ABSTRACT FROM AUTHOR]

The growing space occupancy by the canopy influences the development of natural regeneration. The leaf area index (LAI) is a variable that can be used in ecological studies and in silvicultural decisions process to represent the growing space occupancy in a stand. It is especially useful in mixed forests, as it is better at capturing the complexity of forest structure than other density variables. Andean cypress (Austrocedrus chilensis) and coihue (Nothofagus dombeyi) are species of forest importance of the Andean-Patagonian forests, which can grow in mixed formations with productive potential. Being able to determine which are the target structures of these forests to promote regeneration implies knowing how the canopy growing space occupancy affects the growth of advanced regeneration. The objective of this study was to evaluate the relationship between the canopy LAI and its distribution in the species and height strata with the height increment of advanced regeneration of Andean cypress and coihue. The height increment of the saplings shows an opposite tendency to the LAI of the canopy, although this relationship is significant only for coihue. For this species, the growth of the saplings is favored below a canopy LAI close to 4. In turn, the height increment, especially for coihue, is negatively influenced by a greater participation of coihue in the canopy LAI. From the results, it is inferred that, in order to stimulate the growth of the regeneration of both species, it is necessary to keep, by thinning, the LAI below 4 in the sectors where it is necessary to promote the regeneration of coihue, and above 4 to promote the Andean cypress regeneration. [ABSTRACT FROM AUTHOR]

In the last 20 years, Bolivia has shown progress in the recognition of indigenous rights to land and forests for the development of traditionally excluded populations and as potential tools for environmental conservation. In this study, we use a variety of data collected over 15 years to delay the effect of the conflict between indigenous people and colonizers. We show that the recognition of territorial rights is not enough for indigenous populations in situations of conflict with other populations. Conflicts result in the degradation of resources, institutional weakening, and a general aggravation of their situation of vulnerability. The institutionalism of the Bolivian State acts in a biased manner and imposes great challenges for the fulfillment of indigenous rights. [ABSTRACT FROM AUTHOR]

The taper-volume relationship is an essential tool for planning silvicultural management in forests with the final aim of promoting the distribution of products. The objective of this study is the generation of a compatible model that allows an accurate estimation of the taper-volume of Abies religiosa in several regions of Mexico. A data set of 2608 values was considered for the analysis of the information; the model was simultaneously adjusted by seemingly unrelated regression (SUR) for the estimation of compatible parameters. The model generated coefficients of determination with fit levels higher than 97 %, roots mean square less than 0.40, biases lower than 0.11, with certainty to model each forest region, which are complemented with their respective Akaike information criteria (AIC). In most cases, the shape factor of the species went from neiloid to paraboloid. This information will be useful for timber forest inventories. [ABSTRACT FROM AUTHOR]

The article revised the history of the Bosque Nacional Alexander von Humboldt in 1965. Since the first forestry law in 1963. The usage model of forest resources on the peruvian Amazon has been in constant evolution due to diverse drivers at multiple scales, as for example the changes in the country's economic model. As a long process of changes on national politics framework of forest management, there has been a loss of important referents. A distinct example of this was the first forestry law with its tool on forest management: Bosques Nacionales (National Forests). The motive behind this research is to make evidence of the evolution process on the national politics of Bosques Nacionales by the case study of the Bosque Nacional Alexander von Humboldt by assessing spatial, economic and social dynamic at multiples scales of the constantly changing territory. We aim to comprehend the direct relationship between migratory flows associated to the demand on economic activities in respect to land use. Deforestation is operationalized as the relationship of multiples impacts (legal framework, creation of road axes and demographic growth) which will be approached with an interdisciplinary methodology that allows quantifying these changes in forest cover and building a model of future deforestation of the forest by the use of geographic information systems. [ABSTRACT FROM AUTHOR]

The use of forest biomass for energy production represents one of the current alternatives considered by the country for its energy development. However, not all the information on the real potential of this resource is available at the enterprise level, which limits the timely planning of its management and sustainable use. The present work contributes to solve this situation by developing a methodology for the zoning and evaluation of the potential of residual forest biomass for energy purposes at the enterprise level. This methodology integrates data, management restriction criteria, results of previous research and Geographic Information System tools, which allows processing, analyzing and updating information on forest areas and their energy potential, based on data generated by forest management. The validation of the methodology, in its three stages, is carried out in the agroforestry enterprise La Palma, province of Pinar del Río. Seventy-six percent of the areas with a viable harvesting index are determined, 54.27 % of which are classified as very high, 0.35 % as high and 12.14 % as medium, with an annual residual forest biomass potential of 82,048.94 tons and an energy potential of 22,205 tons of oil equivalent. Three zones of high potential for energy purposes are defined: north and south of the Unidad Empresarial de Base Viñales, and the southern part of La Jagua. The results of the validation of the methodology show its viability, relevance and novelty for the company's economic, environmental and social management. [ABSTRACT FROM AUTHOR]

Co-management processes illustrate some of the current characteristics of the relationships between indigenous peoples and the state in Canada. This article discusses the workings of a forest co-management institution between the Innu Nation and the provincial government of Newfoundland and Labrador based on two examples: the loss of a communal tent and the management of a forest infestation. These examples demonstrate different ideas of responsibility among participants of the co-management process, showing its limitations. [ABSTRACT FROM AUTHOR]

The purpose of this research is to analyze the impact of the excellence-oriented management control process on the development of capacities in agroforestry enterprises, taking the Macurijes Agroforestry Enterprise as a case study. For this purpose, the alignment between the processes and the criteria of forest management for excellence was determined; indicators were defined in order to evaluate the level of enterprise performance with respect to excellence and strategic lines for continuous improvement were proposed. As a main result, the contribution of the excellenceoriented management control process to the effective use of the enterprise's capabilities in terms of the satisfaction of its stakeholders was demonstrated. As a general conclusion, it is deduced that the adoption of this approach contributes to achieve important economic, social and ecological benefits derived from the effective use of all the enterprise's capabilities. [ABSTRACT FROM AUTHOR]

In Cuban forest sector enterprises, the application of control tools is linked to the process management approach and, in this field, sustainable forest management criteria and indicators are one of the instruments used, although their use is not systemically linked to the strategic management and management control of the sector's enterprises, which reduces the effectiveness of the decision-making process and limits the scope of management. The objective of this contribution focused on proposing a set of criteria and indicators of forest management to evaluate the level of performance of enterprises in the sector on the road to excellence. An exploratory and descriptive research was carried out using a procedure based on a qualitative methodology, which made it possible to identify the main processes of criteria and indicators of sustainable forest management applied at national and international level, codify and categorize them, and formulate a set of four criteria and twenty-seven indicators of forest management for excellence and a map of cause-effect relationships among them. The proposed criteria and indicators of forest management for excellence summarize the elements to be addressed for sustainable forest management and, where appropriate, integrate issues inherent to the enterprise activity in a coordinated and balanced manner with its subsystems. [ABSTRACT FROM AUTHOR]

Native forests intervene in the global carbon cycle (C), given their role as CO2 sequestrators. The objective was to estimate the stock and the annual C capture rate in forests of the Espinal (Entre Ríos). Six forests were evaluated, estimating aerial tree biomass, C stock and C capture rate using local allometric models and growth rates by species. The biomass content ranged between 52.13 and 111.82 t DM/ha, on average 92.68 + 23.13 t DM / ha. The C stock averaged 43.99 ± 10.43 t/ha, varying between 26.02 t/ha and 52.78 t/ha. It was observed a high heterogeneity between forests, according to their specific composition and diameter structure. The C capture rate ranged from 0.52 to 0.95 t C/ha/year, equivalent to a capture of between 1.94 and 3,49 t CO2/ha/year. This study generates relevant information for the design of native forest management strategies that contribute to mitigate the global climate change. [ABSTRACT FROM AUTHOR]

The study developed an empirical model for predicting the dominant height (H) and site index (SI) of Gmelina arborea Roxb. plantations considering biophysical and stand variables. Data from 160 stands located in the Andean, Caribbean and Pacific regions of Colombia were used. The Chapman-Richards model was selected for predicting H and SI of each stand. A correlation analysis identified the relative spacing, elevation and precipitation as variables related to SI. A multiple linear regression model with these variables explained 70 % of the total variation observed in SI. These variables included in the H model allowed to increase the fit index by 30 % and reduce the absolute error and mean square error by 40 and 41 %, respectively. The developed models are suitable for estimating productivity in areas with-out a history of forest plantations, adding flexibility and predictive capacity in a changing environment. [ABSTRACT FROM AUTHOR]

In Prosopis caldenia forests, currently, the main activity is cattle rearing. Almost all research focuses on the herbaceous component, losing sight of the value of the forest resource and the implications of its management on the forage resource. The objective of this work is to evaluate forage availability based on forest cover, apply a model of diameter classes that allows predicting the evolution of forest mass and establish the relationship between the evolution of forest cover and forage availability. For this, forage availability was measured under and outside the projection of woody canopies, in two covers: open (10-15 m² ha-1) and closed (25-30 m² ha-1). Afterwards, through a model of diameter classes, it was sought to predict how the parameters of forest mass would evolve. The results of the herbaceous component showed that, up to 15 m² ha-1 of basal area (BA), there is no significant decrease in forage availability (approximately 2,700 kg ha-1). Regarding the forestry component, in a projected period of 10 years, 6.68 m³ ha-1 would be obtained, representing 9.61 % of total standing volume. The relationship between canopy coverage and BA showed increase of 3.18 % per BA unit (R² = 0.96). This would allow projecting their participation by diameter class to propose improvement cuts that allow conducting these systems at coverage levels that do not significantly affect forage yield. [ABSTRACT FROM AUTHOR]

Given that interest in studies of the Spanish presence in the North of Morocco between 1912 and 1956 has been renewed in recent years, this work aims to explain the details of the policy that the Administration of the Protectorate developed regarding the use of cork between 1944 and 1956. After a thorough analysis of the existing documentation, we analyzed the events that followed since the monopoly concession to the company "Industrias Corcheras del Marruecos Español" of all uses of cork until the appearance of what in those years was known as cork fever, a process where the inherent conflict caused by those who were looking exclusively for their own benefit joined the paths and which was fueled at the last years by the Spanish presence under the independence winds that devastated the Protectorate. All this without forgetting, the share of responsibility of both the company and the spanish administration that failed to carry out the enormous expectations that had been generated. [ABSTRACT FROM AUTHOR]

The use of allometric equations in the estimation of the commercial volume of wood allows to plan the management Forestry In that sense, the objective in this work was to select the best allometric models to estimate the volume of wood in G. crinita trees, for this, trees between 13.09 m high and 10.58 cm DAP were used on average. For the determination of the best model, the highest adjusted coefficient of determination R² (˃ R²Aj), lower coefficient of variability (˂ CV%) and lower Furnival index (IF) were considered. Of the 17 existing allometric models for forest species, two were suitable, the model: ln (V) = a + b ln (D) (R² = 0.93, CV = 11.93%, IF = 0.003444) and the model that uses the combined variable Log: ln (V) = a + b ln (D² *H) (R² = 0.91, CV = 11.93%, IF = 0.003444), likewise, a third model proposed in this study: ln (V) = a + b ln (D2 ) + c ln (D * H) - d ln (D² *H) (R ² = 0.98, CV = 11.93%, IF = 0.003444), also presented the best fit to estimate the commercial volume of G. crinita at 31 months of age. However, the use of the Husch model is recommended, as it is easy to apply, since it only uses the diameter at chest height (DBH) as an independent variable. [ABSTRACT FROM AUTHOR]

The Ministry of Agriculture, Fisheries and Food of the Government of Spain pointed out that the forestry industry accentuates its great diversity of species and trees and a multifunctionality of goods and services. The contribution of the wood industry pointed to a wide range of indirect economic activity (extensive livestock farming, nature tourism, fire extinction) of the Spanish forestry sector. In order to protect these activities and the natural environment in general, the Spanish Forestry Strategy was developed, a forestry policy program for the sustainable management of private and neighborhoods forests, as almost 70% of Spanish forests are private. Spain was among the 130 countries that agreed on National Forest Plans for the development of a comprehensive forest management policy. Therefore, the general objective of this research was to investigate the evolution of the forestry sector in Spain during the last two decades of the 21st century, based on two variables: employment and foreign trade. To this end, an inductive method was used to carry out a quantitative and descriptive analysis, based on secondary sources of information. The result required the identification of the main sectors of the national forest industry (wood, pulp, paper and/or furniture), the positive evolution of the Spanish forest sector and the significant investment in forest policies such as fire extinction. [ABSTRACT FROM AUTHOR]

The management of forest seeds in Ecuador, in relation to their storage, is still insufficient, in particular the Cinchona pubescens Vahl. The objective was to determine the quality of the seeds and the best methods of seed storage of C. pubescens, using different times, containers and conditions. Seed collection was in Intag, Imbabura. The factors under study were: storage time, types of packaging and storage conditions. The quality of the seeds was determined at the time of harvest and in each treatment. Purity reached 76.5%, the weight of 1,000 seeds was 0.31 g and the humidity content was 14%. In the first storage trial, no germination was observed in any treatment from the first month. In the second trial, the best storage method was transparent cover stored in refrigeration for one week, which showed 9.25% germination power. Cinchona pubescens seeds lose their viability quickly, which becomes null after one month of storage. [ABSTRACT FROM AUTHOR]

The site index is the main estimate for evaluating the productivity of a forest, as it makes it easy to classify stands according to their productive potential. The objective of the present work was to determine the productivity of Pinus pseudostrobus var. oaxacana through the guide curve method, by adjusting different forest growth models. The Michailoff model statistically presented the best fit. However, the Prodan model better represents the growth pattern of Pinus pseudostrobus var. oaxacana, although statistically the models are similar, showing high significance in the relationship between growth in height and age. [ABSTRACT FROM AUTHOR]

The Lacandon Maya were settled in the Lacandon forest since the 17th century; their experience and knowledge allow them to know and manage different natural elements, like the Native Stingless Bees (nsb). The present research registered the species of nsb and the differentiated knowledge about them in Nahá, Chiapas. From 2015 to 2018, through work with key collaborators and entomological collections, the species of NSB identified by the local population of the Flora and Fauna Protection Area of Nahá (ffpan) were determined. Later a questionnaire was applied to 68 heads of family, all males, to estimate the level of knowledge they have and the uses they give to the native stingless bees, according to age ranges. A total of 15 species of native bees were registered, of which honey is obtained mainly from four: Tetragonisca angustula (Ajyus), Scaura argyrea (K'amas kap'), Plebeia frontalis ( Ak chip kap) y Melipona solani ( Jach K'ojo'). We registered a differentiated knowledge of the heads of family in Nahá about the 15 species of nsb based on their behavior, morphology and the places where they live. The general tendency is the loss of knowledge, and it is accentuated among the young people. The causes are related to the weakening of the transmission's mechanisms of knowledge, the decrease of the recollection activities and the absence of management of colonies in their homegardens, as well as the arrival of products that substitute honey and wax, offered at lower prices. [ABSTRACT FROM AUTHOR]

This article aims to know the territorial impact of the community forest management (CFM) in the Sierra Norte de Puebla (SNP) during the term 2003-2017. The CFM is understood theoretically as a way of collective organization and environmental governance. Territory is understood as a reflection of the social behavior. This work uses a quantitative methodology based on analyzing the economic-environmental indicators, such as production volumes, management plans, subsidies, land use changes. Likewise, field visits and interviews were carried out for the qualitative analysis. Having analyzed the results, it is concluded that the forest cover did not undergo any loss after the CFM. Quite the opposite, it increased in 8% (64.33 Km.). As a conclusion, it could be said that the CFM model applied in the SNP has had positive impacts on the territory. [ABSTRACT FROM AUTHOR]

The design of public policies is aimed at raising the quality of life of the population. Human beings are the protagonists of sustainable development, assimilating new ethical values in the process of helping to transform their society, where different policies based on forest ecosystem services would help such development allowing the opportunity to capture income for the maintenance of their ecosystems. The research started from the opportunity provided by forest ecosystems services in the municipality of Pinar del Río, Cuba, to design policies that establish their payment, by those natural and legal persons who benefit from said services and do not contribute monetarily to raise funds for its maintenance, hence the objective of this, was aimed at proposing a procedure for the management of public policies associated with the payment for forest ecosystem services in the municipality of Pinar del Río, Cuba. [ABSTRACT FROM AUTHOR]

The objective of this article is to contribute to the reflection on the contributions of complexity to forest development, based on the Peruvian case, which could serve as a guide for other Latin American countries. The article gathers the proposals that arose in three days called "Complexity and Forest Development", organized by the Chapter of Foresters of the Departmental College of Lima of the Association of Engineers of Peru, carried out between 2018 and 2019. It was concluded that the disciplinary and sectorial approach of forest administration is insufficient to address the complexity of reality. Consequently, in order to address forest development from an innovative perspective, there is a need to incorporate the approach to complexity from the sciences of complexity and complex thinking, which translates into new ways of thinking and acting. [ABSTRACT FROM AUTHOR]

In Mexico, most repopulation of managed temperate forests is natural and stands have different densities. Models of mortality assume a constant rate of decrease for all ages, site indexes and densities. The objective of this study was to determine mortality rates in three initial densities and construct a growth and yield system (GYS) for Pinus patula in the presence of hardwood species in the region of Zacualtipán, Hidalgo, México. The data used was from three inventories conducted in 2013, 2014 and 2016 at 160 sites, 400 m2 each. A Hossfel IV model based on the dominant height as anamorphic-type growth pattern described productivity. Mortality model fit generated annual decrease rates of 2.47, 1.17 and 0.81% with densities above 2000, between 1000 and 2000, and less than 1000 trees ha-1, respectively. The GYS showed that the highest yields correspond to the initial density of 2000 trees ha-1 and the estimated volume rotation ranging from 24 to 27 years. With hardwoods (5%) present in the site, starting at the first 5 years, estimated volume rotations were found between 20 and 23 years. In a site index (SI) 36, the volume of pine was greater than the total volume (the sum of pines and hardwoods), while at SI 18, 24 and 30, the differences were not as significant. Biomass was greater in all the sites with pines and hardwoods since these latter species concentrate a larger amount of biomass in their structure. In more productive sites (SI 30 and 36), hardwoods tend to affect final volume yield of pine. Therefore, the application of silvicultural treatments is necessary to decrease the proportion of hardwood species. [ABSTRACT FROM AUTHOR]

The study was carried out in the area of "El Franco", Guisa municipality, Granma province, Cuba, The objective of the research was to characterize elements of the operations in the forest exploitation of the species Pinus maestrensis Bisse. Information from the database of the forest management project of the Empresa Agroforestal Granma, a Digital Terrain Model and an Integrated Geographic Information System for Forest Management were used to calculate the density of the road network. Through field observation, the organizational collection system was classified and extraction, collection and loading activities were described. The result was that the area has a road network composed of 23,3 km of 1st, 2nd and 3rd category roads distributed in 35,7%, 17,9% and 46,4% respectively with a total density of 41 m\ha_1 and trails that do not fully comply with the geometric characteristics established for forest roads. The logging areas have a ring pattern, with the abandonment of commercial-sized logs and the use of wood handling techniques that cause health and safety problems, showing an insufficiently planned harvesting system. [ABSTRACT FROM AUTHOR]

Governments are currently facing the challenge of designing and managing public policies that harmoniously integrate economic, social and environmental issues to ensure sustainability in development. Given that there is a lack of use of the existing potential in the ecosystem services and the way they are managed from the public administration, the objective was set to characterize the state of the management of the payment for forest ecosystem services in the municipality of Pinar del Río. This was done based on an analysis of the primary and secondary sources of information. As theoretical methods, the historical and logical and the systemic were used, and as empirical methods, the measurement and the expert method. Associated with the theoretical and practical methods, the following procedures were used: analysis, synthesis and abstraction. The following techniques were used to collect, process and analyze information: survey, interview and document analysis; descriptive statistics were also used to arrive at conclusions through the use of Minitab 17 software. In the diagnosis carried out, it was found that municipal decision makers do not articulate actions that integrate national, sectorial and territorial interests in terms of the use of financial resources coming from the establishment of payment for forest ecosystem services, which favor the politicaleconomic- social recognition of these, in addition, it is necessary to manage public policies to conserve and protect the environment. [ABSTRACT FROM AUTHOR]

Innovation activities at any level of the economy must be systemically articulated and integrated, so that they generate the necessary synergies between the different actors, to promote development and achieve higher levels of income, benefit and diversification of productions. Thus, the Cuban forestry sector is of vital importance for the socioeconomic development of the country, both for the social and environmental contribution made by forests and for their contribution to satisfying the demands of strategic sectors in terms of products and services; however, the inadequate functioning of the innovation process, among other causes, does not allow it to meet these demands. This paper aims to propose the components of the system for innovation management in the forestry sector in Cuba. Theoretical and empirical methods were used, such as analysis and synthesis, inductivedeductive, content analysis, interview, survey and analysis of the network of actors, supported by the UNICET and NETDRAW 6,645 software. This allowed identifying the main strengths and weaknesses of the innovation process in the sector and proposing the components that should structure its innovation system. All the above contributes to the improvement of the sector's innovation process and serves as a benchmark for the design and implementation of policies and strategies, regarding its innovative performance and its contribution to the country's socioeconomic development with a view to the year 2030. [ABSTRACT FROM AUTHOR]

Introduction: Swietenia macrophylla King (Mahogany) is the most commercially important tree species in Southeastern of Mexico and is used as a guide in forest management. Therefore, knowing its age and growth rates is essential for the sustainability of timber harvest. Objective: Estimate the age (Et) from the 'step time' (Tp) method and calculate the absolute (TCA) and relative (TCR) growth rates for Swietenia macrophylla in Quintana Roo, Mexico. Methods: Equations were adjusted to calculate TCA and TCR with periodic re-measured for 15 years of the normal diameter (d) in 403 S. macrophylla trees in Felipe Carrillo Puerto, Quintana Roo, Mexico. Tp and Et were determined for the calculation of the annual current increase (ICA) and average annual increase (IMA), to define the commercial and technical shifts. Results: The maximum TCR was reached at 28 cm of d (0.015 cm year-1) (thinning application), whereas the highest TCA (0.69 cm year-1) and lower Tp (3.5 years) at 55 cm of d (commercial shift). The maximum ICA when considering Et was 1.43 cm in the 50 cm of diametric category with an IMA of 0.67 cm year-1 at an age of 75 years, while the technical shift (ICA = IMA) was reached at 96 years (increments of 0.78 cm year-1). Conclusions: Through periodic measurements of the normal diameter in S. macrophylla it is possible to obtain its age, these results also can be used to elaborate management programs and apply silvicultural practices that propitiate the diametric increase in Quintana Roo. [ABSTRACT FROM AUTHOR]

Forests through forest-management are important carbon sinks (C) for the planet because they help mitigate climate change caused by greenhouse gases. Both forest type and management conditions will determine the amount of C captured. The objective of this study was to build a growth and yield system (SCR) to estimate the volume of Pinus patula and above-ground tree C stored in forests with forest management in Zacualtipán de Ángeles, Hidalgo, Mexico. Since volume shows a close relationship with biomass and C in a forest stand, it is possible to integrate these components within an SCR to model the dynamics of above-ground C sinks at the stand level. Data were obtained from 160 sites of 400 m2 systematically established in chronosequence of stand-ages within an intensive site monitoring of C. The system was composed of equations of dominant height, basal area, number of trees, volume, biomass and C for P. patula and broadleaf species. The site indices (IS) obtained were 15, 20, 25, 30 and 35 m at the base age of 40 years. Volume rotation occurs on average at 29 years of age, which indicates that the 40-year rotation used in the region can be shortened by applying intensive silvicultural work, such as heavy thinning to maintain a sawmill-oriented product distribution. The inclusion of the broadleaf species proportion component allowed to model the interspecific competition and the effect on the commercial species (pine). The SCR adequately modeled the behavior of biomass and C, estimated C at 89.1 Mg ha-1 for IS 30 at 35 years. This value is similar to those obtained in natural and managed forests in the region. [ABSTRACT FROM AUTHOR]

the main objective of this article is to reflect on how bioethics can shed light on forest development that is more committed to life in general. The study focuses on Peru; however, specialized bibliographic information from other countries with tropical forests is considered. It is concluded that, although there are important scientific advances in knowledge about tropical forests and expectant certified experiences in forest management, there is not enough scientific certainty to guarantee their ecological sustainability. This is a product of both the ecological complexity of tropical forests and the socio-cultural complexity of the forest sector; which demands approaches that complement disciplinary approaches with interdisciplinary and transdisciplinary perspectives. The reality of forests is multidimensional, interdimensional, multiscale and multitemporal; this condition cannot be grasped by forest management plans that lie on the paradigm of a rational and empirical science. Although there are valuable measures aimed at conserving forest biodiversity and provisions to combat illegal logging, illegal trade and trafficking of wildlife, these measures to reduce illegality are still not enough. To the date there is no specific guidance on respect to forest life in all its manifestations, and in addition to that, attempts seeking to conserve the species of flora and fauna are disarticulated. [ABSTRACT FROM AUTHOR]

Se presenta una introducción en la que los editores discuten artículos sobre la cuestión sobre temas como el conocimiento territorial, la gestión de los recursos forestales y las políticas públicas para la gestión del territorio.

The objective of this paper is to assess the current situation of forest seed production and conservation in Ecuador, through the analysis of documents. It is noted that there are two strategies for the conservation and/or production of seeds in the country. In situ conservation shows results from the selection of seed sources from different actors: the EcoPAr foundation selected 20 in Andean forests in the Sierra, the Municipality of Quito identified 28, while Solidaridad Internacional installed 33 in Orellana, among others. Ex situ conservation developed alternatives such as: cryopreservation, long term, medium term, in vitro and field. The National Germplasm Bank of The National Autonomous Institute of Agro-Livestock Research has 72 species with 85 accessions, the Bank of the Private Technological University de Loja has 500 species in more than 800 accessions and there are also seven botanical gardens. The efforts made and the different experiences obtained are isolated. There are limitations of constructive and technological infrastructure, human resources, as well as deficiencies in the inter-institutional coordination of inventories and management plans of the forests that have seed sources. [ABSTRACT FROM AUTHOR]

The aim of this work is to review the research carried out on the prevention of forest fires in Mediterranean jarales through the enhancement of mycological resources. Cistus ladanifer (jara pringosa) is a Mediterranean pyrophyte scrub widely distributed in the Iberian Peninsula, which is associated with numerous species of fungi, some of which are highly valued, such as the Boletus edulis. Adequate management of these areas would contribute to reduce the risk of fire and increase the economic benefit derived from the use of fungi. Therefore, the main objective of this review is to find the best management practices of Mediterranean ecosystems dominated by C. ladanifer, to increase mycological production and prevent forest fires. An experimental design was established in which they analyzed the communities of fungi associated to different treatments, knowing the diversity and fungal production associated to the ecosystem, under different parameters of management focused on the prevention of fires. The production of the most interesting species was modelled. As a main result, the high fungal diversity associated with these ecosystems was demonstrated, supporting the conservation interest of these habitats. As a general conclusion, it can be deduced that the adequate management of these areas would produce important economic benefits derived from the mycological exploitation in these ecosystems that traditionally have been considered unproductive and are generally found in economically disadvantaged rural areas. [ABSTRACT FROM AUTHOR]

From a governmental perspective, where the state is the owner of forests, regulatory frameworks for forest management are typically asymmetric in relation to the dynamics of the local community. This research identifies, by using study cases, the relationship form of the human being with the forest, in order to establish the favorable aspects and the barriers that face the materialization of the self-management as the base of effective governance in the management of the natural tropical forests. The review of 60 case studies was addressed, of which only 26 present a conceptual systematization with specific features of the principles proposed by Ostrom for "resources of common use" (RCU). The analysis concludes that the most recurrent principle in the studies is the "coherence between rules of appropriation and provision", while the least considered is the "monitoring of resources", which shows that communities always establish rules; however, the importance of monitoring is not clear for them. [ABSTRACT FROM AUTHOR]

Teak is a commercial tree species of high interest, mainly for its outstanding wood physical and mechanical properties, growth rates and adaptability. The aim of the study was to evaluate the genetic variation of growth and tree quality traits among 40 half-sib families. Using data from a 4-year-old progeny test, narrow sense heritabilities, genetic gains, and genetic correlations were calculated, as well as a ranking of families according to total wood volume per hectare. All the families showed a higher survival rate ranging from 73-100%. The genetic gains by selecting 30% of the best families were of 2.93% for diameter, 4.83% for stem volume, 11.97% for total volume per hectare, 6.53% for crown projection area, 4.26% for branch insertion angle and 14.42% for number of basal sprouts. Three families with superior productivity and potential for the establishment of high yield plantations were identified. [ABSTRACT FROM AUTHOR]

La Molina is one of the districts with the bigger green areas and ecological awareness in the city of Lima. The Universidad Nacional Agraria La Molina (UNALM) represents about half of the green areas in the district; being the Schinus molle L. «molle serrano» the second most abundant tree species in the campus and one of the most planted in Lima. This native tree with recognized cultural importance is widely used in the arboriculture crops for its ornamental and rustic character, resistant to the drought and plagues; whose top formed by hanging branches offers shade and when having a fast replacement of foliage, it is able to filter the air capturing particles in suspension and CO2. However, it has been observed the presence of burls along the shaft and branches in trees of this species altering its ornamental character and representing a probable risk. Therefore, the internal structure of the tree was studied using the Arbosonic 3D forest tomograph and/or the resistance of healthy wood, wood with burl and wood with rot by means of the physical and mechanical properties of the wood: basic density (DB), resistance to bending or modulus of rupture (MOR) and rigidity or modulus of elasticity (MOE). The results determined the absence of Schinus molle L. tree risk due to the presence of burls, evidencing the importance of the use of the forest tomograph in the management of arboriculture crops in Lima. [ABSTRACT FROM AUTHOR]

Current forest management approaches require management strategies that identify where and when to carry out harvest activities that satisfy the demand for wood products while forest ecosystem services are conserved. This work makes the TRIAD zoning approach operational through a mathematical model to optimize the forestry planning process. This approach proposes dividing the forest under management into an intensive harvesting area, an extensive harvesting area, and a conservation area, according to the production objectives established. A mixed integer nonlinear optimization model was formulated to maximize the present value of gains derived from timber production, while satisficing operative and biodiversity conservation restrictions associated with the forest community of San Pedro El Alto, Oaxaca, Mexico. The model was solved through a genetic algorithm, in their simple version (GNS), and two variants of it (GN2 and GN3). The process allowed completing three objectives: 1) to propose and validate a model capable of generating comparable solutions to the current management scenario in the community, 2) to compare three different solution algorithms, and 3) to offer an efficient algorithm to solve similar optimization problems. [ABSTRACT FROM AUTHOR]

A new methodology is presented to design synthetic arboreal communities, with emphasis on forest management in deforested regions. This methodology is based on the potential distribution of native tree species of Mexico in the lower part of the Usumacinta river basin in southeastern Mexico. The potential distributions of native species were obtained from the probability of occurrence calculated by the Maxent ecological niche model, using presence data, from an area delimited by the municipalities of Balancán and Tenosique, Tabasco, Mexico, which has had a strong deforestation in the last decades. A synthetic arboreal community is proposed for this study area, which consists of the five species that have the largest areas of potential distribution, according to the calculations made with a geographic information system, which covers a considerable area of the study region (1,951.9 km2), maximizing the reforested area. Two of the species studied are listed within some type of national or international standard on threatened species. [ABSTRACT FROM AUTHOR]

Non-timber forest products (NTFPs) are important in the local economy, their use is a viable alternative for the management and conservation of forests, serving as a motivating activity for communities to value the forest economically, socially and environmentally. The NTFPs were investigated in five rural communities of the Zapotillo Canton, with the purpose of knowing the non-timber forest products of vegetable origin, traditional and current uses and the tendency of the generational loss of knowledge in these communities. A survey was applied to 255 inhabitants of the five communities using a form with 11 questions, which was used to collect information on the knowledge and uses of plants that provide NTFPs. The use of 87 plant species that provide NTFPs is reported, within 82 genera and 61 families, distributed among 31 trees, 38 shrubs and 18 herbs. The best known NTFP categories are: food and beverages, human medicine and fodder. The most commonly used species in the studied communities are Bursera graveolens, Eriotheca ruizii and Tecoma castanifolia. Older adults know more about the use of the species, due to their relationship with the forest and family traditions; adults recognize and use little, and young people are not aware or do not want to accept that they know and do not use them; men and women know plants equally. In the forests of Zapotillo there are species that provide NTFP, the local adult population knows its use, the use is scarce, which causes the generational loss of knowledge. [ABSTRACT FROM AUTHOR]

This paper disccuses the Nelder designs used in forestry research from 1962 to the present. These designs have a circular, semicircular or quadrant shape and can be used on small plots to evaluate a plantation's growth at different densities. Because the treatments are not random, the data cannot be analyzed by traditional analysis of variance. Another disadvantage of its use is mortality, which can affect the data of the lost tree and the four adjacent ones; therefore, the effect must be reduced by seeking replication of the design and, in the early stages of the experiment, replanting. [ABSTRACT FROM AUTHOR]

The objective of the article that is presented below, is to analyze, from an interdisciplinary approach, the conceptual developments and concrete effe cts that the notion of 'sustainable development' has had in the department of Boyacá since the constitutionalization of the notion in the 1991 letter The analysis is developed from the growing socio-environmental con:flicts in the department related to extractive processes of hydrocarbons and minerals, in contrast to processes of defense and environmental govemance of strategic ecosystems such as the case ofhighAndean forest highly sensitive to anthropic intervention. [ABSTRACT FROM AUTHOR]

This work aimed at evaluating the horizontal, diametric and volumetric structures and the diversity of arboreal-shrub vegetation in two areas of the Caatinga biome after 27 years of application of silvicultural systems. The first area is in the Seridó Ecological Station and the second is in Pedro Cândido Farm, in the county of Serra Negra do Norte-RN, Brazil. The silvicultural systems used were: general cut of all individuals of arboreal-shrub species; selective cut of arboreal-shrub species with base circumference > 8 cm; general cut of all individuals of arboreal-shrub species and subsequent burning of crop residues; general cut of all individuals of arboreal-shrub species with subsequent burning of crop residues and removal of stem from soil. In each area, 16 subplots of 400 m2 were delimited and individuals with circumference at breast height (CBH) > 6 cm were measured. The basal area provided by silvicultural systems was evaluated and compared with the results recorded before the experiment. Stem density, volumetric yield and diversity data were compared by the Tukey test. The selective cut provided the highest values of absolute dominance and volumetric production and favored the development of a more balanced diametric structure. The different forms of use of the areas influenced density and absolute dominance, and volumetric production. [ABSTRACT FROM AUTHOR]

The demand for forest resources has encouraged intensification in the use of forests, and therefore the need to evaluate their effect on birds. The purpose of this study was to evaluate the diversity of birds in a managed forest. Transects and points of intensive counting were established in representative areas of the silvicultural treatments that are applied in the ejido Acolihuia, municipality of Chignahuapan, Puebla. The silvicultural treatments considered were selective logging, release cutting, seed tree cutting and thinning. Thirty-five species were identified: 30 were residents and 5 migratory species. Five species have some category of endemism, and we register Myadestes occidentalis, subject to special protection by the nom-059-semarnat-2010. Significant differences were observed in abundance and richness between silvicultural treatments. The highest richness and diversity were recorded in areas managed by the silvicultural development method. The species similarity between treatments is low or intermediate, suggesting that species can be conserved during the rotation of treatments. In a scenario of persistent deforestation, and increasing demand for forest products, the promotion of sustainable forest management can contribute to the conservation of bird diversity. [ABSTRACT FROM AUTHOR]

Aboveground biomass is critical to assess the amount of carbon stored in forest covers. One way to obtain accurately estimates of the aerial biomass is through expansion factors, which use standing trees volume data, taken during forest inventories. Our objective in this study is to estimate total and structural aerial biomass using allometric models and biomass expansion factors (FEB), in order to evaluate their applicability in forest inventories for Eucalyptus urophylla S. T. Blake clones in commercial forest plantations at Tabasco, Mexico. Random samplings on seven plantations was utilized to select 93 trees, from one to seven years old trees, from which the total biomass and structural components were determined. We propose two systems allometric models fitted as seemingly unrelated equations in order to estimate aerial biomass. The average bole biomass percentage (Bs), branches (Bb) and foliage (Bf) was of 91.42, 5.54 and 2.03 respect to the total biomass (Bt). The Bs ratio increased with tree size and Bb and Bf decreased after three years. The average FEB of the Bt and Bs was 510.09 kg m-3 and 472.56 kg m-3 of bole volume. The biomass conversion factor from the bole to total biomass was 1.17. Data from a forest inventory allowed to estimate an average of 156.08 m-3 ha-1 of timber volume and 80 Mg ha-1 of aerial biomass in the plantations. The fitting, bias and percentage of aggregate difference statistics indicated that the proposed systems are reliable for aerial biomass estimation. [ABSTRACT FROM AUTHOR]

The use of non-timber forest products (NTFPs) can create development opportunities for local populations, but this requires certain conditions. In Mexico, the use of NTFP considered by the government to be "at risk" is regulated by "wildlife conservation management units" (UMAs), a policy instrument that seeks to reconcile biological conservation with local development. Its effectiveness varies according to the context in which the instrument is applied. The majority of UMAs in the south of the Mexico, particularly for NTFPs, have shown less than encouraging results, partly because their design and implementation do not take into account the complexity and diversity of the conditions present in rural areas in this part of the country. Based on ethnographic observation, in-depth interviews, and socioeconomic surveys, this article analyzes the implementation of a palm (palma camedor) UMA in two rural villages in the Lacandon rain forest in Chiapas, Mexico. We argue that these palm UMAs assume a simplified conception of the complex reality of these communities, in which the implementation of the management instrument alters the local balance of power. Its bureaucratic design and overregulating character generates discretionality, simulation, and corruption, which in turn accentuates exclusions and favors local elites. [ABSTRACT FROM AUTHOR]