A computer vision system for the recognition of trees in aerial photographs

Increasing problems of forest damage in Central Europe set the demand for an appropriate forest damage assessment tool. The Vision Expert System (VES) is presented which is capable of finding trees in color infrared aerial photographs. Concept and architecture of VES are discussed briefly. The system is applied to a multisource test data set. The processing of this multisource data set leads to a multiple interpretation result for one scene. An integration of these results will provide a better scene description by the vision system. This is achieved by an implementation of Steven's correlation algorithm

Assessment of Forest Damage in Croatia Caused by Natural Hazards in 2014

Background and Purpose: Recent natural disasters (ice-breaks, torrents, floods) that affected five Croatian counties caused significant damage on forest stands and forest infrastructure. Since in Croatia there is no common methodology for fast and reliable assessment of forest damage, the aim of this paper is to develop and present methodology for rapid damage assessment and to prescribe urgent recovery measures, as well as to provide first preliminary results of the total damage to forests. Materials and Methods: An attempt was made to develop the methodology which would rely on existing legislations, regulations, instructions and experiences for forest damage assessment as much as possible. Estimation of forest damage was based on field observations, spatial data of forest management units and data from the existing Forest management plans. Results: According to conducted assessment, forests of Primorsko-goranska County are the most affected by the overall damage caused by ice-storm. Major damages occurred both on the forest and on forest roads. Ice-storm also caused serious damages on forests and on forest roads in Ličko-senjska County and Karlovačka County, while floods and torrents caused damages on forest roads in Zagrebačka County, Sisačko-moslavačka County and Karlovačka County. Money-wise, the total forest damage amounts 942 252 183 €. Conclusions: Methodology for rapid damage assessment presented in this paper resulted on first preliminary estimate of range, intensity and cost of forest damage caused by recent natural disturbances. More precise data on forest damage will be known after the implementation of the proposed emergency recovery measures. Also, certain improvements of methodology in terms of precision and collection of data may be achieved by incorporating remote sensing methods

Pollution-Induced Forest Damage, Optimal Harvest Age and Timber Supply: Some Theoretical Considerations

This paper examines the relationships of pollution-induced forest damage, optimal age of stand harvest, and timber supply from a theoretical perspective. Since future levels of forest damage will be important determinants of harvesting and silvicultural practices and thus of wood supply, they must be explicitly taken into account in any realistic analysis of alternative scenarios of future forest decline and appropriate policy responses

Relating remotely sensed forest damage data to wind data: storms Lothar (1999) and Vivian (1990) in Switzerland

This study compares the surface wind speed and forest damage data of two exceptionally severe winter storms, Vivian 1990 and Lothar 1999. The study area comprises the region that suffered damage in Switzerland. The wind speed data were derived from simulations of MeteoSwiss (Federal Office of Meteorology and Climatology), measurements during the storm periods and expert analyses of the data. The remotely sensed forest damage data were provided by the Federal Office for the Environment and the forest cover data by Swiss Federal Statistical Office. We compared data on the peak gust and maximum average wind speed, with data on the spatially related forest area and forest damage area, and found some clear differences in the correlations between the different wind data and forest damage. Our results point generally to the damage-causing role of near-surface gusts at maximum wind speeds during the storm. These tended to be spatially distributed on a fine scale. In only a few cases were the results statistically significant. However, these results could probably be improved with better wind data. For example, gust measurements spatially closer to forests or simulations of gusts at maximum wind speed could be produced with a spatially higher resolutio

Inventory strategies for monitoring and evaluation of forest damage

Under global change, increasing stresses on forests require strategies for monitoring and mitigation of damages caused by pests and diseases. While the threats to forests increase, so do the possibilities to set up efficient monitoring programmes and detect forest damage by utilising new technologies. This thesis focuses on strategies for forest damage inventories where different auxiliary data are combined to improve information for pest mitigation programmes. First, the efficiency of National Forest Inventories (NFIs; or similar inventories) for detecting and estimating state and change of forest damage across large regions was evaluated. NFIs were found efficient for assessing widely distributed damage, but unable to detect clustered and local outbreaks with adequate precision. Second, targeted forest damage inventories directed to areas with potential or suspected damage were investigated. It was found that two-phase sampling for stratification taking the first phase information from existing NFIs was an efficient strategy. Remotely-sensed auxiliary information and post-stratification was shown to further improve the precision. Third, the use of a new sampling design was evaluated: the local pivotal method (LPM), which spreads the sample in the multi-dimensional space of available auxiliary data. The LPM was found to be more efficient than simple random sampling in all scenarios and, depending on the allocation of the sample and the properties of the auxiliary data, it sometimes outperformed two-phase sampling for stratification. Thus, the LPM may be a valuable tool for practical forest damage inventories. Fourth, the cost-plus-loss method was applied to evaluate inventory strategies in a pest mitigation context. If inventory costs are large, it is especially important to quantify the inventory efforts necessary to evaluate the need for mitigation. The optimal sampling effort necessary for deciding whether or not a defoliator outbreak should be treated was quantified. Double sampling was found to be a cost-effective sampling strategy, i.e. the size of the second phase sample was determined based on the estimates from a small first phase sample. As an overall conclusion, the thesis points out the importance of making use of existing information in setting up effective inventories of forest damage and of using appropriate sampling strategies for making use of the information in the best possible way

THE AUTHORITY OF LOCAL GOVERNMENTS IN PREVENTING AND ERADICATION OF FOREST DESTRUCTION

Forest damage in Indonesia has been increasing from year to year, both forest damage caused by illegal logging, forest burning, mining without permits, and plantations without permits have caused state losses, damage to socio-cultural life and the environment, as well as increasing global warming which has become national, regional and international issues. Forest damage caused by forest fires carried out by the community both for clearing agricultural land and for plantation land, burning forests and land seems to never stop threatening the lives of people in Indonesia because most Indonesian people become farmers, especially those in the regions. who must clear forests for agricultural land. This is because local governments have the authority to regulate and limit the permits of companies operating in the forestry, plantation and mining sectors in their respective areas. Therefore, local governments must make policies and make concrete mitigation in terms of preventing and eradicating forest destruction that occurs in each region

Overview of Austrian Airborne Imaging Spectrometer (AIS) programme and first results

Airborne Imaging Spectrometer (AIS) data collected from eight test areas in Austria were evaluated for their usefulness in forest damage assessment, geobotany, alpine vegetation mapping, and land use classification. Difficulties encountered in installing the SPAM spectral analysis software for use on the image display system and the necessity to adapt existing programs for this task impeded and delayed the analysis of the AIS data. Spectral reflectance curves obtained from a geobotanical test site show a marked increase in reflectance across most of the measured spectrum for metal stressed spruce trees compared with nonstressed spruce trees

Forest damage and forest supply chains: a literature review and reflections

Timber supply is affected by natural disruptions such as storms, wildfires, and insect infestations, which modify timber properties and disturb the supply to forest industries. Climate change threatens to increase the prevalence of forest damage and supply chain disturbances. This review analyzed the research between 2000 and 2022 on the effects of forest damage on wood supply chains and management measures to handle such disruptions. The review identified 23 studies from North America, Europe, and Australia and analyzed them regarding damage type and impact, research approach, and key findings. The literature on the topic covers the leading causes of damage: fire, wind damage, and insect infestation. In some cases, climate change was identified as the underlying cause of the supply disruptions. Research approaches involved calculations of consequences, scenario modeling, optimizations, and qualitative studies. This review identifies the essential considerations for successfully handling supply chains after forest damage. Robust supply warrants a range of adaptations, including choices for forest establishment, forest management methods, and collaborative planning. In addition, future research themes based on findings in the retrieved papers are suggested

Does forest damage have an economic impact? A case study from the Italian Alps

The aim of this paper is to take stock of the situation regarding the main types of damage to forests and their respective economic consequences, with reference to a case study in the Italian Alps (Trentino province). Each kind of damage (wind and snow, defoliation, fire and tillage) has been analysed in terms of its impact on four forest functions (production, protection, tourism-recreation and carbon sequestration) and evaluated in monetary terms. Market value was used to estimate the production and carbon sequestration functions, replacement cost method for protection, and contingent valuation for tourism-recreation. Applying desk research on damage caused by the main biotic and abiotic factors to this particular case study led to estimate a annual damage of about € 1,633,595 equal to € 4.73 per hectar. This can be considered a lower bound estimate of possibly greater damage. Another interesting result emerged from the evaluation exercise is that the wealth of information produced through monitoring and scientific research in the last twenty years does not readily lend itself to economic analysis.forest damage, forest functions, interaction between damage and functions, economic valuation, Alpine forests

Analisis Dampak Perubahan Kerapatan Hutan Di Kabupaten Muna

Forest damage in Muna Regency Southeast Sulawasi has reached a critical point. Based on data from Muna Regency Department of Forestry, the size of teak forest in Muna today is approximately 500 ha compared with 60.000 ha in 1970-s. This study aims to clarify and analyze forest density level in Muna Regency Southeast Sulawesi in 2007 and 2009, present information on the decline of forest density in every sub-district in Muna Regency Southeast Sulawesi, and discover the impacts of forest damage in Muna Regency Southeast Sulawesi. Forest density levels in 2007-2009 were classified by processing the images of Landsat TM using NDVI (Normalized Different Vegetation Index) formula which utilizes band 3 and band 4. Changes of forest density in 2007-2009 were calculated by matching method and calculated by software ArcGIS. Forest damage impact analysis was performed without checking the and only based on information stakeholders The results showed that the highest forest density in Muna regency in 2007 was in Bonegunu Sub-district and in 2009 was in Tongkuno Sub-district. Based on the processing result of forest density level in Muna regency, in 2007 the size was 144.694,2 ha, while in 2009 it was 78.007 ha. Based on the data it can be seen that the size of the forest in Muna Regency declined by 66.957,2 ha largely in Tungkuno Sub-district. Forest damage in Muna Regency ecologically impacted the extinction of a primate called Macaca ochreata brunnescens, temperature change in Muna Regency which continues to rise and increase of dengue fever cases, increase of poverty, and natural disasters such as drought, landslide, flood, and declining water quality