Tree Resources Research Articles

Assessing the Role of Gender in Identifying and Prioritizing Local Ecosystem Services of Trees in Croplands

The overall objective of the study was to assess and compare the role of gender in identifying and prioritizing the ecosystem services of trees in croplands. The research was carried out in croplands and species inventory in each cropland was conducted during field observations of every tree species by interviewing the local farmers and/or villagers. A questionnaire containing both close-ended and open-ended questions were designed to collect information about the role of gender in identifying and prioritizing the ecosystem services supplied by each tree species in croplands based on local communities. A total of 15 ecosystem services were identified from trees in croplands by both men and women. The number and type of ecosystem services identified by men and women were different. The differences could be due to different access and benefits from ecosystem services. As a result, their perception and knowledge of ecosystem services could also vary. After identification of each ecosystem service, a paired two-tail t-test was conducted whether the list of individual score values given to each local ecosystem services identified by both men and women were the same or not. The statistical result of the paired t-test showed that the score values of all the ecosystem services that are only identified by both men and women were not statistically significant. This can imply that the commonly identified ecosystem services have more or less similar importance to men and women. The findings in this research demonstrate that ecosystem services identification might cause gender biases on women due to neglected control and access to the ecosystem services of trees in croplands which in turn could have an impact on tree resource management, conservation, and development interventions. Therefore, integrating women in ecosystem service access and control can help build various experiences of gender and balanced institutions which can aid collective and effective tree and forest resource management and to maximize the benefits for all beneficiaries of the ecosystem services.

Зачем России нужен рентный подход к ценообразованию на лесные ресурсы?

Раскрываются причины неудовлетворительной работы в России такого рыночного механизма ценообразования на лесные ресурсы, как аукционы. Рассмотрен рентный подход к определению начальной цены предмета торгов при продаже права использования лесов. На основе анализа сложившейся ситуации и зарубежного опыта приведены рекомендации по улучшению действующей системы ценообразования на лесные ресурсы. The purpose of this article is consideration of the main reasons that prevent Russia from taking full advantage of the potential of the market mechanism of pricing for forest resources, and possible ways to overcome these obstacles. This is especially important for the assessment of tree resources, which provide 2/3 of the countrys forest income. The method used to achieve the goal of the study is to consider the concept of perfect competition in relation to the forest resources markets of Russia, Europe and North America. The possibility of using a multifactor statistical model of the price of forest resources is analyzed. The conditions required for use by the residual value method are analyzed. There are proposals for creating such conditions in Russia. The amount of payment for the use of state forests in Russia, as in many other countries, is set based on the results of a public auction. To determine the initial auction price using fees. In 1997, for the first time, the Russian government set the AllRussia minimum wage rates for standing timber on a rental basis 1. However, bidding results are unsatisfactory. In recent decades, the State Duma and the Government of Russia have repeatedly changed the size and method of calculating payments for forest resources. To improve the pricing system, it is necessary to understand the peculiarities of the Russian forest resources market. In Russia, almost all forests are in federal ownership. There are no private forests. Forests are under the joint jurisdiction of the Russian Federation and its subjects. The Federal Government sets the rates of payment per unit of measure for forest resources. The subjects of the Federation organize the use of forests. Forests are used by private business. The main form of obtaining the right to use forests is a longterm lease (up to 49 years). The main tenants are large woodworking firms, so the number of new transactions for the transfer of forests for use during the year is small. The domestic market for roundwood is small, since tenants themselves process most of the harvested wood. The domestic roundwood market is the sellers market (oligopsony), so prices are low. State statistics for forest products is unsatisfactory. In these conditions, the main problem of using the residual value method for calculating the initial price of the subject of the auction is to obtain reliable information. To solve this problem, it is proposed to amend the forest legislation and other measures.

Vulnerability analysis of Indian sandalwood tree using GIS

There is a declining trend in the distributions of natural sandalwood tree resources worldwide. Most of the Indian sandalwood trees face survival threats due to anthropogenic causes and climate change in the future. This research focusses on identification of safer areas from anthropogenic threats due to access from road networks and settlements and also focusses on the impact of climate change over the sandalwood trees in 2050. According to a previous research (Baybutt PSP 21(4):269–275, 2002), these kinds of threats get minimised as the distances from roads and human habitations increase. So, ‘anthropogenic threat index map’ has been prepared separately for roads and settlement data of Tamil Nadu, which is the study area of this research. Similarly, ‘vulnerability index map’ has been prepared pertaining to the same study area, keeping in consideration the effect of climate change in the future. This map has also been clipped with the identified safer areas from anthropogenic threats. So, the ultimately resulting map could be used for prioritising the areas before commencing the artificial sandalwood tree plantations in the future. This research infers that about 65.98% of Tamil Nadu is vulnerable to anthropogenic threats from human settlements and also about 78.14% of Tamil Nadu is vulnerable to anthropogenic threats from roads. Ultimately, the anthropogenic threat analysis shows that about 72.06% of the area of Tamil Nadu is vulnerable to anthropogenic threats due to human interventions from both roads and settlements. This research also infers that there is 17.54% vulnerability for the identified safer areas in Tamil Nadu to pose threats due to climate change in the future.

Mass flowering of Fagus crenata does not depend on the amount of stored carbohydrates in trees

Stored carbohydrates in trees do not act as key requirements for mass flowering in a masting species, Fagus crenata. Many tree species exhibit high interannual variability in flower production at population level, called mass flowering. These species may need to store a certain amount of carbohydrate resources in trees for flowering. Based on this assumption, we hypothesized that masting tree species would blossom heavily when carbohydrates were sufficiently stored up in some specific organs. To test this hypothesis, we studied the relationship between stored carbohydrates in various organs just before the season of flower bud initiation and the number of flowers in the following year in a typical masting species, Fagus crenata (Fagaceae), over 10 years. In addition, we estimated the carbon accumulation period required for flower production by radiocarbon (14C) contents of inflorescences in this species. During the study period, the individuals studied flowered synchronously about every 2 years, but levels of the flowering magnitude were different from each other. Total nonstructural carbohydrate (TNC) concentrations also exhibited large interannual variations, while the long-term trend of TNC over the 10-year observation period showed a general increase in all the investigated tree individuals. There was no significant relationship between the TNC concentrations in each organ and the number of flowers produced in the following year, including the massive flowering event in 2006 when all the selected trees flowered heavily. Fagus crenata produced inflorescences using carbon resources assimilated mainly in the year when the flower buds were formed. These results suggest that the storage of carbohydrate resources might not be a limiting factor in the occurrence or frequency of flowering in this species.

Understanding landscape and plot-scale habitat utilisation by Malayan sun bear (Helarctos malayanus) in degraded lowland forest

Malayan sun bear (Helarctos malayanus) is a forest-dependent species globally threatened by loss of suitable habitat and hunting. Understanding how sun bears utilise habitat in more degraded landscapes is increasingly important for the effective conservation of the species. We studied how landscape and plot attributes affect sun bear habitat use along a gradient of logging disturbance in a lowland forest site of Sumatra. We conducted surveys of bear claw marks to indicate sun bear habitat use at plot and landscape scales, and inform forest restoration strategies that benefit the conservation management of the species. We recorded 12 habitat features and the presence/absence of claw marks in 262 plots in four different habitat types. We reduced the number of habitat variables using Principal Components Analysis (PCA), resulting in four derived habitat factors. We used these factors in a Discriminant Analysis to refine habitat classifications of plots, and modelled presence/absence of claw marks using the PCA factors in a binary logistic regression. We inventoried tree species in a subset of randomly selected plots with claw marks alongside paired control plots with no claw marks. We compared tree community compositions in these plots using ANOSIM and SIMPER analyses. Based on claw mark signs, sun bear habitat use appeared to be non-random and was significantly associated with gradients of increasing habitat intactness, from non-forest habitat to least disturbed forest. Two PCA factors explained the probability of bears utilising a given habitat, which increased with tree biomass and decreased with understorey cover. At the plot level, tree family and species compositions were significantly different between plots without and with claw marks. The abundance and use of Olacaceae stems was significantly higher in plots with claw marks. Incorporating forest restoration strategies that enhance or increase more intact forest and the availability of key tree resources should benefit the conservation of sun bears and encourage natural forest regeneration in these degraded landscapes. We also emphasise the conservation value of degraded forest habitats for this species while ensuring bear movement and connectivity within modified landscape matrices.

Allometric models for estimating biomass, carbon and nutrient stock in the Sal zone of Bangladesh

Allometric models are commonly used to estimate biomass, nutrients and carbon stocks in trees, and contribute to an understanding of forest status and resource dynamics. The selection of appropriate and robust models, therefore, have considerable influence on the accuracy of estimates obtained. Allometric models can be developed for individual species or to represent a community or bioregion. In Bangladesh, the nation forest inventory classifies tree and forest resources into five zones (Sal, Hill, Coastal, Sundarbans and Village), based on their floristic composition and soil type. This study has developed allometric biomass models for multi-species of the Sal zone. The forest of Sal zone is dominated by Shorea robusta Roth. The study also investigates the concentrations of Nitrogen, Phosphorus, Potassium and Carbon in different tree components. A total of 161 individual trees from 20 different species were harvested across a range of tree size classes. Diameter at breast height (DBH), total height (H) and wood density (WD) were considered as predictor variables, while total above-ground biomass (TAGB), stem, bark, branch and leaf biomass were the output variables of the allometric models. The best fit allometric biomass model for TAGB, stem, bark, branch and leaf were: ln (TAGB) = -2.460 + 2.171 ln (DBH) + 0.367 ln (H) + 0.161 ln (WD); ln (Stem) = -3.373 + 1.934 ln (DBH) + 0.833 ln (H) + 0.452 ln (WD); ln (Bark) = -5.87 + 2.103 ln (DBH) + 0.926 ln (H) + 0.587 ln (WD); ln (Branch) = -3.154 + 2.798 ln (DBH) - 0.729 ln (H) - 0.355 ln (WD); and ln (Leaf) = -4.713 + 2.066 ln (DBH), respectively. Nutrients and carbon concentration in tree components varied according to tree species and component. A comparison to frequently used regional and pan-tropical biomass models showed a wide range of model prediction error (35.48 to 85.51%) when the observed TAGB of sampled trees were compared with the estimated TAGB of the models developed in this study. The improved accuracy of the best fit model obtained in this study can therefore be used for more accurate estimation of TAGB and carbon and nutrients in TAGB for the Sal zone of Bangladesh.

The complete chloroplast genome of a critically endangered agarwood tree, Aquilaria crassna (Thymelaeaceae)

Aquilaria crassna Pierre ex Lecomte is a principal agarwood tree resource. It has been listed as a critically endangered species. The complete chloroplast genome of A. crassna was assembled based on next-generation sequencing. The plastome was a quadripartite circular shape with 174,830 bp in length, including a large single-copy (LSC) region of 87,450 bp and small single-copy (SSC) region of 3346 bp, separated by two inverted repeat (IR) regions of 42,017 bp each. The chloroplast genome contained 125 genes, including 79 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. The overall GC content of the whole genome was 36.7%. The phylogenetic tree showed that three species of Aquilaria formed one monophyletic clade with 100% bootstrap value.

Ritual, Landscapes of Exchange, and the Domestication of Canarium: A Seram Case Study

It is widely accepted that a major historic pathway to agriculture in the tropics has been via the management of forest and reliance on tree resources. Using ethnographic and ethnobotanical data from Seram in the Moluccas, this article illustrates how this might have happened in one part of Island Southeast Asia. Several species of the genus Canarium produce proteinaceous nuts that have been ethnographically, historically, and prehistorically shown to be an important part of local diets. To understand how food-procurement systems evolve, we need to examine the biocultural dynamic established over the long term between different species, types of arboriculture, and cultivation strategies. One factor was likely subsistence pressure, but exchange has also been an important driver in relation to procurement of Canarium in particular and to the modification of forest landscapes more generally, hence the term "landscapes of exchange." While theorists tend to assume dietary need is the main cause of agricultural change, the social and ritual significance of particular species often drives ecological and genetic change in anthropic contexts.

Allometric Equations for Estimating Silk Oak (Grevillea robusta) Biomass in Agricultural Landscapes of Maragua Subcounty, Kenya

Grevillea robusta is widely interplanted with crops in Maragua subcounty, a practice that enhances biomass quantities in farmlands. However, quick tools for estimating biomass of such trees are lacking resulting in undervaluation of the farm product. This study sought to develop allometric equations for estimating tree biomass using diameter at breast height (DBH) and tree height as predictor variables. Tree biomass was computed using thirty-three (33) trees randomly selected from 12 one hectare plots established in each of the four agroecological zones (AEZs). DBH of all Grevillea robusta trees per plot was measured and three trees were selected for destructive sampling to cover the variety of tree sizes. Regression analysis was used to develop equations relating DBH/tree height to biomass based on linear, exponential, power, and polynomial functions. The polynomial and the power equations had the highest R2, lowest SEE, and MRE values, while DBH was the most suitable parameter for estimating tree biomass. The tree stem, branches, foliage, and roots biomass comprised 56.89%, 14.11%, 6.67%, and 22.32% of the total tree biomass, respectively. The mean tree biomass density (12.430±1.84 ton ha−1) showed no significant difference (p=0.09) across AEZs implying no difference in G. robusta agroforestry stocks across the AEZ. The allometric equations will support marketing of tree products by farmers and therefore better conservation and management of the tree resource.

Sustainable Development and Forest-Based Industries: Main Considerations and Policy Measures. The Bulgarian Example

AbstractIndustrial policy determines the industry's orientation for growth, in line with the economic development stage. The main objective of this article is to establish the sustainability of the relationship between the development of forest resources, on the one hand, and their use in wood and furniture products in the Republic of Bulgaria, on the other hand. The main tasks are to find out the sustainability in the production of timber and products from it, to assess the tendency of development and needs of policy measures. The methods used include statistical methods for trend analysis, descriptive methods and others. Forestry is a clear example of the transformation of natural resources into consumer products, where sustainability in the development of society can easily be disturbed. Forestry policies should support the use of tree resources in products with the highest possible added value.

Evaluation of the Genetic Diversity and Differentiation of Black Locust (Robinia pseudoacacia L.) Based on Genomic and Expressed Sequence Tag-Simple Sequence Repeats.

Understanding the genetic diversity and differentiation of the genetic resources of a species is important for the effective use and protection of forest tree resources. Ex situ development is a common method for the protection of genetic diversity and an essential resource for users who require ready access to a species’ germplasm. In this study, we collected seeds of black locust (Robinia pseudoacacia L.) from 19 provenances, covering most of its natural distribution; we randomly selected 367 tender leaves with well-grown and different maternal strains from this group for further analysis. Forty-eight simple sequence repeat (SSR) primers were successfully selected from 91 pairs of SSR primers using native-deformation polyacrylamide gel electrophoresis. In addition, we identified identical genotypes among all individuals and evaluated the quality of the markers. From this, 35 loci were confirmed for analyses of genetic diversity and differentiation of the black locust provenances, which contained 28 expressed sequence tag-derived simple sequence repeats (EST-SSRs) and 7 genomic DNA-derived simple sequence repeats (G-SSRs). We observed high genetic diversity among the native black locust provenances, from which Wright’s fixation index and molecular variance suggested that a majority of the genetic differentiation variation could be attributed to within-provenance differences. The genetic distance and identity results indicated that geographic distance was not a dominating factor influencing the distribution of black locust. This is the first study to evaluate provenance genetic variation in native black locust samples using two types of SSR markers, which provides a comprehensive theoretical basis for ex situ conservation and utilization of genetic resources, with an emphasis on breeding applications.

Assessment of plant species diversity associated with the carob tree (Ceratonia siliqua, Fabaceae) at the Mediterranean scale

Background and aims – The thermophilous woodlands of the Mediterranean region constitute reservoirs of genetic resources for several fruit trees. Among them, the carob tree (Ceratonia siliqua) is a key component of traditional Mediterranean agroecosystems but its ecology was never assessed at the scale of its whole distribution area. Fortunately, phytosociological literature shelters invaluable resources for several issues in conservation, among them the possibility to analyse plant biodiversity at regional or continental scale. Here, we present the results of a comprehensive survey of the phytosociological literature associated to carob tree. Methods – We collected 1542 floristic relevés performed in 18 geographical areas distributed around the Mediterranean in which the presence of C. siliqua was recorded. Species composition of the plant communities was analysed by multivariate ordination and hierarchical classification, and species diversity was evaluated by rarefaction and prediction analyses of Hill numbers. Key results – Multivariate analyses revealed that plant communities associated with the carob tree are well differentiated between the Western and Eastern basins. A wider range of floristic differentiation is revealed in the Western basin where the vegetation reaches its maximal heterogeneity. By comparison, in the Eastern basin the plant assemblages associated with the carob tree are more homogeneous and with a lower species richness but a higher Simpson diversity. Conclusions – The large ecological range of the Mediterranean carob trees is potentially an important evolutionary legacy for the conservation of genetic resources and seed sourcing for new uses such as restoration ecology.

Design and evaluation of a sequence capture system for genome-wide SNP genotyping in highly heterozygous plant genomes: a case study with a keystone Neotropical hardwood tree genome

Targeted sequence capture coupled to high-throughput sequencing has become a powerful method for the study of genome-wide sequence variation. Following our recent development of a genome assembly for the Pink Ipê tree (Handroanthus impetiginosus), a widely distributed Neotropical timber species, we now report the development of a set of 24,751 capture probes for single-nucleotide polymorphisms (SNPs) characterization and genotyping across 18,216 distinct loci, sampling more than 10 Mbp of the species genome. This system identifies nearly 200,000 SNPs located inside or in close proximity to almost 14,000 annotated protein-coding genes, generating quality genotypic data in populations spanning wide geographic distances across the species native range. To provide recommendations for future developments of similar systems for highly heterozygous plant genomes we investigated issues such as probe design, sequencing coverage and bioinformatics, including the evaluation of the capture efficiency and a reassessment of the technical reproducibility of the assay for SNPs recall and genotyping precision. Our results highlight the value of a detailed probe screening on a preliminary genome assembly to produce reliable data for downstream genetic studies. This work should inspire and assist the development of similar genomic resources for other orphan crops and forest trees with highly heterozygous genomes.

Linking land use and forestry transition with depopulation in rural Nepal

Migration borne depopulation has been emerging as a new dimension of conservation challenges. Existing body of knowledge, however, lack in-depth understanding of this emerging dynamics of depopulation and its forestry implications. Aiming to analyze implications of migration borne land use transition, this study investigated the nature and impacts of migration in rural communities involved in managing community forestry and other tree resources This study was grounded in the experiences and perceptions of community forest users groups in Parbat and Lamjung districts and applied a pragmatic approach to social science, involving the collection of both qualitative and quantitative data. A total of 218 semi-structured interviews, two focus group discussions and three stakeholders’ consultations were conducted. Spatial changes in land use were analyzed using Landsat images of 2000 and 2016 and other existing land use maps.The study found decreasing trend of population growth and identified out-migration of local youth as the main driver. Identified underpinning causes motivating for migration include desire of higher education, employment and resettlement, poverty and poor access to education, markets and other opportunities. This study found negative correlation between migration and farming activities but positive correlation between forest and tree coverage. Forests and other woodland increased but none forest area, most of which were farmlands, decreased. Community forests were getting denser but they lack proper management, abandoned farmlands were turning into bushes, which have increased the risk of forest fire. This study showed very poor understanding of REDD+ and related issues at community level and suggests substantial gaps in policies and procedures to translate migration borne land use transition into opportunities for generating multiple benefits including carbon finance as an additional benefit. Banko JanakariA Journal of Forestry Information for Nepal Special Issue No. 4, 2018, Page: 130-143

Мониторинг интродукционных ресурсов Кулундинского дендрария и выделение ценного генофонда для защитного лесоразведения

On the example of the Kulunda arboretum the materials of monitoring of introduction resources of trees and bushes are given. The success of their introduction into the culture of protective afforestation is based on a detailed study of ecological and biological features, the experience of introduction in new conditions. Due to the increased anthropogenic load in recent years, the range of woody plants used in the protective forest plantations of arid areas requires updating. The problem statement includes the allocation of a valuable gene pool for the creation of seed bases and the cultivation of adapted planting material. It is shown that in the conditions of the Kulunda steppe the introduced species in the protective afforestation are not widely used yet, the range of tree species is poor (Betula pendula Roth., Populus balsamifera L., Pinus sylvestris L., Larix sibirica Ledeb., Salix fragilis L.). Accompanying woody plants are presented by Acer negundo L., Malus pallasiana Juz., Ulmus pumila L. Other tree species are used in protective afforestation on a limited scale. The purpose of the evaluation introduction the sustainability of the gene pool of Salted arboretum on the basis of a comprehensive monitoring and study their biological features under conditions of Kulundinskaya steppe for protective afforestation. Kulundinsky arboretum was established in 1977, it is located on the territory of the West Siberian agroforestry experimental station (plot 49098 m2, cadastral number 22:23:010003:0014). Type of soil – chestnut, light-loamy. The main reserves of humus are concentrated in the upper horizon and with a depth decrease from 2.7 to 0.6%, the depth of groundwater 5-6 m. It was revealed that the species composition of trees and shrubs of the Kulundinsky arboretum includes 143 taxa from 52 genera and 25 families. Among the economically valuable generic complexes are representatives of the family Rosaceae. It is established that the representatives of the family Rosaceae, as an introduction resource for the enrichment of forest reclamation complexes and the formation of comfortable living conditions of the population, is one of the largest in taxonomic composition of wood species and important for multifunctional use. Methodical approaches to carrying out monitoring of introduction of resources, the proposed method of calculation introduction the resistance of plants to new conditions including the characteristics group (winter hardiness, drought tolerance, pobegoobrazovatelnost ability, growth in height, generative development, possible method of propagation in culture) and the ratio of collection Fund on indicators and the dimensions of the scales. Materials on monitoring of introduction resources of the Kulundinsky arboretum of the Federal CENTER of Agroecology of the Russian Academy of Sciences on assessment of the adapted gene pool for protective afforestation will be used to develop measures for biodiversity conservation and rational use of economically valuable plants; based on the data obtained, promising species for the enrichment of protective forest plantations of the kulundin steppe were selected.

Impact of management regime and frequency on the survival and productivity of four native tree species used for fuelwood and charcoal in the caatinga of northeast Brazil

The seasonally dry deciduous forest (Caatinga) of northeast Brazil is under intense human pressure, and sustainable use of its tree resources for fuelwood is a pressing concern. An experiment was conducted to ascertain which management techniques (coppicing, pollarding or crown-thinning) permit the highest survival of trees and optimal timber production. Four much-utilised tree species: Croton sonderianus, Mimosa ophthalmocentra, Mimosa tenuiflora and Poincianella pyramidalis (syn. Caesalpinia pyramidalis) were studied at two sites in Pernambuco State. The impact of each harvesting regime was evaluated over a six-year period, with additional variables including wet-season versus dry-season harvesting, and three-year versus six-year harvesting cycles. The best performing tree species varied between sites, with M. tenuiflora providing the highest yields with all treatments at Sertânia and M. tenuiflora and Poincianella pyramidalis at Serra Talhada. The optimal management regime did not vary between species. Crown-thinned trees produced limited regrowth with the lowest mortality rates, and when ultimately coppiced growth appeared to have been stimulated. Pollarding was intermediate and coppicing was the poorest management strategy. Trees which were harvested twice, in both 2005 and 2008, had much lower overall production than those which had only been harvested once in 2008. The highest yields were obtained from crown-thinned trees which were coppiced in 2005 or 2008. Management decisions must consider local environmental conditions in the selection of the tree species used to produce fuelwood, however, the optimal management strategy for high production and low mortality is consistently low impact, infrequent crown thinning. There was considerable difference in the findings between the study sites (e.g. in the distribution of statistically significant results), and also in the impacts of treatments on mortality between the four species. The results can be used to guide species-level management regimes that minimise tree mortality, contributing to long-term fuelwood productivity.

Analysis of the lost value of street trees in the context of the possibility of replacement and compensatory planting based on the case of selected streets in Warsaw

Street trees grow in extreme habitat conditions and are exposed to high anthropogenic pressure. This study presents changes that occurred in the resources of street trees in the selected part of Praga-North, a district located near the center ofWarsaw, between 2011 and 2016. During this period, the number of dead and removed trees was determined and the assessment of the lost value was conducted. The compensatory value was evaluated as well. The replacement value was estimated in the examined area based on the difference between the value of the removed and newly-planted trees. The study also shows the real number of conducted compensatory planting for the environmental loss. The research was conducted with the objective to determine the changes in the urban forest in the selected, highly-urbanized part ofWarsaw. The study evaluated the extent of losses between the removed and newly-planted trees that allowed to assess the range of substitutes needed to be planted.

Transient synchrony among populations of five foliage-feeding Lepidoptera.

Studies of transient population dynamics have largely focused on temporal changes in dynamical behaviour, such as the transition between periods of stability and instability. This study explores a related dynamic pattern, namely transient synchrony during a 49-year period among populations of five sympatric species of forest insects that share host tree resources. The long time series allows a more comprehensive exploration of transient synchrony patterns than most previous studies. Considerable variation existed in the dynamics of individual species, ranging from periodic to aperiodic. We used time-averaged methods to investigate long-term patterns of synchrony and time-localized methods to detect transient synchrony. We investigated transient patterns of synchrony between species and related these to the species' varying density dependence structures; even species with very different density dependence exhibited at least temporary periods of synchrony. Observed periods of interspecific synchrony may arise from interactions with host trees (e.g., induced host defences), interactions with shared natural enemies or shared impacts of environmental stochasticity. The transient nature of synchrony observed here raises questions both about the identity of synchronizing mechanisms and how these mechanisms interact with the endogenous dynamics of each species. We conclude that these patterns are the result of interspecific interactions that act only temporarily to synchronize populations, after which differences in the endogenous population dynamics among the species acts to desynchronize their dynamics.

Traditional Natural Resource Use and Conservation of Juniper Woodlands in the Arabian Peninsula: A Case Analysis of Raydah Nature Reserve, Southwestern Saudi Arabia ( Exploitation and Conservation of Middle East Tree Resources in the Oil Era: A Study of Human Subsistence Ecosystems in Arab Societies)

Traditional Natural Resource Use and Conservation of Juniper Woodlands in the Arabian Peninsula: A Case Analysis of Raydah Nature Reserve, Southwestern Saudi Arabia ( Exploitation and Conservation of Middle East Tree Resources in the Oil Era: A Study of Human Subsistence Ecosystems in Arab Societies)

Traditional and formal ecological knowledge to assess harvesting and conservation of a Mexican Tropical Dry Forest

This research integrates Traditional and Formal Ecological Knowledge (TEK / FEK) of a Tropical Dry Forest in central Mexico, in order to assess harvesting and conservation of the non-timber forest species. We were interested in: knowing the structure and diversity of the forest community; identifying which are the tree resources of common interest to the users through participatory workshops. A further interest was to identify those resources which are important to local people in terms of preservation; explaining the relationship of the species with some environmental factors; and visualizing which management practices endanger or facilitate the conservation of species. Studied areas were defined and labelled on a map drawn by local informants, where they indicated those plant species of common interest for preservation. Ethnobotanical techniques were used to reveal the TEK and assess harvesting and conservation of the species. With the FEK through community and population ecology, we detected the importance of five environmental factors, obtained various ecological indicators of the vegetation, and studied the population structure of the relevant species. The FEK was analyzed using descriptive and multivariate statistics. As a result, low density and small basal area of trees were registered. Species richness and diversity index were similar to other natural protected areas in Mexico. Tree species harvested shown an asymmetric distribution of diameters. Harvesting, elevation, and accessibility were the most influential factors on tree density. FEK demonstrated that TEK is helpful for the assessment of forest harvesting. Ecological analysis complemented the local knowledge detecting that Lysiloma tergemina is a species non-identified for the people as interesting, although we discover that it is a threatened species by over-harvesting. Haematoxylum brasiletto was identified as important for conservation due to its scarcity and medicinal use. Our results advanced on how the traditional harvesting of tree community has contributed to preserve diversity, when comparing with protected areas. Discrepancies between both kinds of knowledge should be reconciled for contributing to the preservation of priority resources by the local society.