Please login first

List of accepted submissions

Show results per page
Find papers
  • Open access
  • 396 Reads
Impact of air pollution on Scots pine stands growing in Poland on the basis of dendrochronological analysis

Air pollution and climate change are two key factors comprising the global change threat to forest health and sustainability. Intensive development of industry in the second half of the 20th century brought significant changes in the level of pollutants emitted into the atmosphere in Poland. Dry and wet deposition of toxic pollutants (mainly SO2, NOx, & NH3), continuing over more than 40 years, has caused serious damage to forest stands. One of the ways describing the effect of industrial emissions on forests is the tree-rings (dendrochronological) analysis, it has been used in our research. We present a brief description of the studies on impact of air pollution on growth of forest growing in the most polluted areas of Poland. The main aim is to evaluate of Scots pine stand degradation caused by the pollutants emitted from the one of biggest polluters of the environment in Poland for over 25 years (1966-1990). We found that pollutant emission caused disturbances of incremental dynamics and long-term strong reduction of growth. Scott pine growing in the vicinity of the nitrogen fertilizer factory showed a dramatic growth reduction after the beginning of the pollution period. Significant decrease in growth was observed for the majority of investigated trees (75%) to the end of the 1990s. The zone of destruction extends primarily in easterly and southern directions, from the pollution source, associated with the prevailing winds of the region. At the end of 1990s decreasing trend stopped and the wider tree-rings could be observed. This situation was related with a radical reduction of ammonia emissions and an improvement of environmental conditions. However, growth of damaged trees due to the weakened health condition is lower than the growth of Scots pine on the reference plot and trees are more sensitive to stressful climatic conditions, especially to drought.

  • Open access
  • 160 Reads
A spatial framework to assess spot fire transmission potential

Spotting is known to be an important fire spread mechanism and cause of fireline breaches during windy conditions, yet current fire modeling systems provide only coarse metrics of spotting behavior that are underutilized in fire operations. We developed a spatial framework to quantify and map potential sources and sinks of spot fire transmission across linear control features based on models of ember production, ember transport, and receiving fuel bed ignition probability. The framework provides several spatially explicit measures of spotting potential conditional on fire extent and weather that are designed to support fire management decisions related to control line selection and resource allocation to tasks such as line prep, retardant application, and holding operations. We evaluate the utility of the framework using two wildfire case studies with growth episodes attributed to spotting. In its current form, the model is most appropriate for relative evaluation of spot fire transmission potential from wind-driven fires. The spotting source and sink metrics may also help managers begin to think prescriptively about the control tactics necessary on both the source and receiving sides of firelines to avoid spotting breaches. Improvements to the input data and component models are needed to progress towards desired estimates of conditional breach probabilities.

  • Open access
  • 79 Reads
A review on the nematicidal activity of volatile allelochemicals against the pinewood nematode

Pine wilt disease (PWD) is caused by the pinewood nematode (PWN), Bursaphelenchus xylophilus. This invasive microscopic phytoparasitic nematode induces pine yellowing and wilting by feeding on pine vascular tissues and resin canals and multiplying rapidly. In Asia, PWD has devastated wide areas of susceptible pine forests, with drastic ecological, economic and cultural repercussions. In 19991, Portugal became its entry point into Europe, most likely through imported goods from Asian countries, and, despite the actions of the authorities, has advanced rapidly into the border areas of Spain, threatening European pine forests. Chemical control has been used in Asia with remarkable success, yet most nematicides are dangerous to human health and the environment. Natural volatile allelochemicals and derivatives are sustainable and ecological alternatives, providing many advantages to commercial nematicides2,3. The present work summarizes available bibliographic information on the most successful volatile allelochemicals showing activity against the PWN and reviews the chemical properties leading to anti-PWN nematicidal characteristics.

Published work reports over 110 allelochemical volatiles, mainly secondary metabolites, with considerable activity against the PWN. These belong to highly active classes of chemical compounds, namely monoterpenoids, phenylpropanoids and aliphatic alcohols, aldehydes, ketones, carboxylic acids, esters and sulphides. Volatiles with highly electronegative elements appear to show increased activity. The top 10 most active allelochemicals (lowest half maximum effective concentration, EC50) were trisulphides, stilbenoids and medium carbon chain length aliphatic alcohols and derivatives.

Future research must deepen the study of the strong structure-activity relationships reported to understand the mechanism of action of these highly nematicidal anti-PWN volatiles. This knowledge is paramount in the establishment of an integrated and sustainable approach to manage PWD in its new forest environment.

1. Mota, M. et al. First report of Bursaphelenchus xylophilus in Portugal and in Europe. Nematology 1, 727–734 (1999).

2. Faria, J. M. S., Barbosa, P., Bennett, R. N., Mota, M. & Figueiredo, A. C. Bioactivity against Bursaphelenchus xylophilus: Nematotoxics from essential oils, essential oils fractions and decoction waters. Phytochemistry 94, 220–228 (2013).

3. Barbosa, P. et al. Bioassays against pinewood nematode: Assessment of a suitable dilution agent and screening for bioactive essential oils. Molecules 17, (2012).

  • Open access
  • 66 Reads
Invertebrates inhabiting fruiting bodies of Heterobasidion spp. on decayed wood of Picea abies

Due to the decomposition of wood and the formation of conspicuous fruiting bodies, saproxylic basidiomycetes not only provide microhabitats for many invertebrate species, but can also cause great losses to forestry. Among these, pathogenic fungi from the genus Heterobasidion are the major causative agents of root rot in conifers of temperate and boreal forests. However, despite the ecological and economic importance, information on invertebrates inhabiting fruiting bodies of Heterobasidion spp. is scarce. Such information can provide a better understanding on how the control of root rot could affect invertebrates, including threatened species, inhabiting fruiting bodies of Heterobasidion spp. These effects can be expected due to changes in microhabitat conditions and substrate availability. The aim of this study was to determine the diversity of invertebrates in fruiting bodies of Heterobasidion spp. growing on decayed wood of Picea abies. The fruiting bodies of Heterobasidion spp. were sampled in autumn 2016 from large dimension logging residuals with an average diameter of 25 centimeters. In the laboratory, invertebrates from 69 fruiting bodies were collected using Tullgren funnel traps. A total of 4987 individual invertebrates, including larvae, representing 16 orders were collected. The samples were dominated by mites, springtails, beetles, millipedes and true flies. None of the invertebrate species found in Heterobasidion fruiting bodies represented a threatened species. The study provided comprehensive data on invertebrates inhabiting Heterobasidion fruiting bodies. It also demonstrated that the control of Heterobasidion root rot is likely not affecting the threatened species of invertebrates.

  • Open access
  • 81 Reads
Bark characteristics of Scots pine logs

The wood of Scots pine (Pinus sylvestris, L.) shows good properties as building and construction timber but also as furniture or pulp and paper and, thus, is commercially one of the most important European tree species. Scots pine are mostly harvested and processed with a high degree of mechanization. In Northeast Germany (federal states of Brandenburg and Berlin), 36 % of harvested Scots pine have a DBH between 7 and 19.9 cm. As a typical industrial wood assortment, a large proportion of the resulting small-sized logs are used in the wood industry to produce boards. Although bark is considered as a by-product or waste product from the industry, no actual study quantifies bark thickness, bark volume, bark mass and bark damage of such Scots pine logs.

Therefore, bark characteristics from 50 logs from 10 different piles were analyzed. Bark volume was quantified using water displacement method, bark mass by weighting, bark thickness with precision caliper and bark damage by tape measurements.

The diameters of the analyzed 150 log discs were normally distributed and the mean value was 12.9 cm. The results showed average bark damages from 11.8 % which were mostly caused during felling and processing the logs with the harvester. No significant correlation was found between double bark thickness (mean: 3.2 mm) and the diameter; whereas fresh bark volume (mean: 5.6 %) and dry bark mass (mean: 3.3 %) were significantly affected by diameter.

As shown for spruce by other authors, bark characteristics may change over time and, therefore, should be measured regularly. Moreover, it was shown that bark parameters are site dependent. Thus, quantifying bark characteristics for economically important tree species in both local and national scale is of great relevance.

  • Open access
  • 142 Reads
Spatial Scenarios of Land Use/Cover Change for the management and conservation of Páramos and Andean Forest in Boyacá, Colombia.

The Andean ecosystems host high biodiversity and are crucial for the provision of ecosystem services, such as water regulation, and their soils are considered as an important agricultural pantry for the country. The aims of this study were to identify the dynamics of land use change, the factors associated to these changes, and potential transformations of páramo and Andean forest, through the modeling of land use change scenarios. Our study area encompasses the mountain ecosystems of the Boyacá providence (Colombia) above 900 m a.s.l. Using satellite images, the change in land use was assessed in two time periods: 1998 to 2010 and 2010 to 2018. Seven transition sub-models were analyzed and associated to 36 explanatory variables. Three future scenarios of land use change were projected for the years 2030 and 2050: trend, agricultural expansion and conservation scenarios. We found a gradual reduction in páramos and Andean forests, together with an increase in secondary vegetation and recurrent change between crops-pastures and secondary vegetation. The transition sub-model with the highest precision value was Páramo to crops-pastures, with a precision value of 80.62%. The most relevant variables explaining land use change were: elevation, distance to roads and distance to protected areas. Most frequent socioeconomic variables influencing the transitions were: agricultural density, number of households and conflict overuse. Our results showed that the scenario with the greatest impact in páramos and Andean forest was the agricultural expansion scenario, where the Andean forest would have a loss of 29% and 41% for 2030 and 2050, and the Páramos 44% and 59% for the same years. Forest and páramos in the central eastern area showed critical losses and highly fragmented distributions in all tree scenarios; hence, we recommend focusing conservation efforts in these areas.

  • Open access
  • 72 Reads
Supply potential and annual availability of timber and forest biomass resources for energy considering inter-prefectural trade in Tohoku region of Japan

To promote sustainable timber and forest biomass utilization, this study estimated technically feasible and economically viable availability considering forest regenerations. This study focuses on five prefectures, namely, Aomori, Iwate, Miyagi, Akita, and Yamagata, and considers the trade between these prefectures. The data used in this study include forest registration (tree species and site index) and GIS data (information on roads and subcompartment layers) from the prefectures for private and communal forests. Additionally, this study included GIS data (subcompartment layers, including tree species) from the Forestry Agency of Japan for national forests as well as 10-m-grid digital elevation models (DEMs) from the Geographical Survey Institute. As a result, supply potentials of timber and forest biomass resources were estimated at 11,388,960 m3/year and 2,277,792 m3/year. Then, those availabilities were estimated at 1,631,624 m3/year and 326,325 m3/year. Therefore, the rate of availabilities to supply potentials was 14.3%. Since timber production, and wood chip usage from thinned woods and logging residues in 2018 were 4,667,000 m3/year and 889,600 m3/year, rates of timber and forest biomass resource availabilities to those values were 35.0% and 36.7%, respectively. Furthermore, the demand was estimated at 951,740 m3/year from 100,000 m3/year with the generation capacity of 5 MW. The rate of forest biomass resource availability to the demand was 34.2%. The rates were increased to 64.1% with additional regeneration subsidy, 173.3% with thinning subsidy, and 181.5% with both subsidies. Thus, the estimated availability with both subsidies met the demand sufficiently in this region.

  • Open access
  • 85 Reads
Empowering Women on Efficient Bamboo Utilization to Support Sustainable Bamboo Resource Management and Conservation in Lake Toba Catchment Area (LTCA) of the North Sumatra Province of Indonesia

Indonesia is blessed with the wonderful and beautiful Lake Toba Catchment Area comprising around 110,000 hectares of lake and 280,000 hectares of land where high diversity bamboo species grow and providing social, cultural and economic benefits to Bataknese community, indigenous to the region. The bamboo resource, however, has not been sustainably managed due mainly to over-cutting relative to growth rates while bamboo cultivation have been insignificant. This study aims to investigate on relevant interventions for achieving sustainable bamboo resource in this region. Data were derived from a questionnaire survey of 154 women and in-depth interviews with 65 respondents in two districts: Simalungun and Karo. In order to identify cause of problem and potential strategies for sustainable bamboo management, a problem tree analysis and three focus group discussions were conducted involving related stakeholders in North Sumatra. Statistical package for social science (SPSS) is used for data analysis. Findings of study shows that (a) strengthening the institutional framework, b) utilizing efficiently, c) enhancing initiatives on bamboo resource conservation and development, and d) promoting local stakeholders are identified as some of potential strategies for sustainable bamboo management. The basic notions are that achieving sustainable bamboo management is feasible only with stakeholders supports, notably local communities, and in this consideration, local communities must be provided with a decent income by efficiently utilizing the resource. Furthermore, bamboo management must be supported by promoting gender equality and empower women related to their control over bamboo plantation and harvesting; access to market and financial resources; processing technology; education and training; and other decision-making opportunities on income, saving, expenditure, etc. The study recognizes that there is a strong relationship (0.712) between decision making authority and women empowerment. However, women are not allowed to take the decisions at social community level due to cultural norms in Bataknese community.

  • Open access
  • 60 Reads
The Value of Recreational Ecosystem Services in India

Forest ecosystem services have been a vital role in human well-being. Particularly, recreational ecosystem services are creating physical and mental well-well being of people. Therefore, the main objective of the paper is to estimate the economic value of recreational ecosystem services provided by two recreational sites such as Nandi Hills and Nagarhole National Park based on the Individual travel Cost Method in Karnataka, India. This study has used a random sampling method for 275 tourist visitors to recreational sites. The present study has also estimated the consumer surplus of the visitors. The result of the study has found that (i) economic value of two creational sites has estimated at the US $ 323.05 million, (ii) the consumer surplus has estimated for Nandi Hills at US$ 7.45 and Nagarhole National Park at US$ 3.16. The main implication of the study is to design the entry fees for the recreational site and sustainable utilization of recreational ecosystem services for the present and future generations.

  • Open access
  • 69 Reads
Comparative morphology of the leaf epidermis in four species of Meliaceae family

Meliaceae is a family of woody species that are very useful for timber and ethnomedicine in Nigeria. However, there is scarce information on their taxonomic description, which is important in realizing their full potentials. Existing floristic studies on members of meliaceae have revealed overlap in key morphological characters like number of lateral nerves, shape, size and number of leaflets. Aside the floral and fruit characters, the use of leaf epidermal characters has proven to be gene-dependent and as such provides stable and less expensive grouping compared to the molecular methods. This study investigated the leaf epidermal and petiole anatomical significance in four species of Melieceae; Azadiracta indica, Cederella odorata, Khaya sensegalensis and K. grandifoliola for taxa delimitation. The choice of leaf for this study is based on their regular availability unlike the flowers, which are seasonal. Plant materials of the species were collected from University of Ibadan, Forest Research Institute of Nigeria and National Center for Genetic Research and Biotechnology in south western Nigeria based on availability. Leaf samples were examined under the microscope for epidermal and petiole anatomical characteristics. Characters like epidermal cell shape, epidermal cell wall pattern, trichome type and stomata abundance were differentiated in the four species. Petiole anatomical characteristics for delimiting the taxa include cuticle thickness, presence or absence of crystal, crystal type and vascular bundles arrangement. The analyzed characters produced two major clusters- Cluster 1: Khaya senegalensis and Khaya grandifoliola; cluster 2: Azadiracta indica and Cederella odorata. Azadiracta indica and Cederella odorata are more closely related species than Khaya senegalensis and Khaya grandifoliola.

The affinity of the studied characters is an evidence of their correlation and supports the relationship existing among the species. These characters support delimitation of the taxa even in fragment condition.