Mapping Forest Disturbances between 1987–2016 Using All Available Time Series Landsat TM/ETM+ Imagery: Developing a Reliable Methodology for Georgia, United States

Forest resources have a high economic value in the State of Georgia (USA) and the landscape is frequently disturbed as a part of forest management activities, such as plantation forest management activities. Thus, tracking the stand-clearing disturbance history in a spatially referenced manner might be pivotal in discussions of forest resource sustainability within the State. The two major objectives of this research are (i) to develop and test a reliable methodology for statewide tracking of forest disturbances in Georgia, (ii) to consider and discuss the use and implications of the information derived from the forest disturbance map. Two primary disturbance detection methods, a threshold algorithm and a statistical boundary method, were combined to develop a robust estimation of recent forest disturbance history. The developed model was used to create a forest disturbance record for the years 1987–2016, through the use of all available Landsat Thematic Mapper (TM)/Enhanced Thematic Mapper (ETM+) data. The final product was a raster database, where each pixel was assigned a value corresponding to the last disturbance year. The overall accuracy of the forest disturbance map was 87%, and it indicated that 4,503,253 ha, equivalent to 29.2% of the total land area in Georgia, experienced disturbances between 1987 and 2016. The estimated disturbed area in each year was highly variable and ranged between 84,651 ha (±36,354 ha) to 211,780 ha (±49,504 ha). By combining the use of the disturbance map along with the 2016 database from the National Land Cover Database (NLCD), we also analyzed the regional variation in the disturbance history. This analysis indicated that disturbed forests in urban areas were more likely to be converted to other land-uses. The forest disturbance record created in this research provides the necessary spatial data and address forest resource sustainability in Georgia. Additionally, the methodology used has application in the analysis of other resources, such as the estimation of the aboveground forest biomass.

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Forest Disturbance Mapping with Sentinel-2 Time Series in Austria

10.5194/egusphere-egu21-7795 ◽

2021 ◽

Author(s):

Markus Löw ◽

Tatjana Koukal

Keyword(s):

Time Series ◽

Forest Management ◽

Time Series Analysis ◽

Bark Beetle ◽

Management Practices ◽

Forest Ecosystems ◽

Forest Disturbance ◽

Spatial Scales ◽

Forest Disturbances ◽

Sentinel 2

Worldwide, forests provide natural resources and ecosystem services. However, forest ecosystems are threatened by increasing forest disturbance dynamics, caused by direct human activities or by altering environmental conditions. It is decisive to reconstruct and trace the intra- to transannual dynamics of forest ecosystems. Therefore, the monitoring of large and small scale vegetation changes such as those caused by natural events (e.g., pest infestation, higher mortality due to altering site conditions) or forest management practices (e.g., thinning or selective timber extraction) becomes more and more crucial. National to local forest authorities and other stakeholders request detailed area-wide maps that delineate forest disturbance dynamics at various spatial scales.We developed a time series analysis (TSA) framework that comprises data download, data management, image preprocessing and an advanced but flexible TSA. We use dense Sentinel-2 time series and a dynamic Savitzky&#8211;Golay-filtering approach to model robust but sensitive phenology courses. Deviations from the phenology models are used to derive detailed spatiotemporal information on forest disturbances. In a first case study, we apply the TSA to map forest disturbances directly or indirectly linked to recurring bark beetle infestation in Northern Austria.In addition to spatiotemporal disturbance maps, we produce zonal statistics on different spatial scales that provide aggregated information on the extent of forest disturbances between 2018 and 2019. The outcomes are (a) area-wide consistent data of individual phenology models and deduced phenology metrics for Austrian forests and (b) operational forest disturbance maps, useful to investigate and monitor forest disturbances, for example to facilitate sustainable forest management.At a forest stand level, we reconstruct the origin date of forest disturbances (FDD &#8211; Forest Disturbance Date). Theses FDD outputs show the spatiotemporal patterns and the development of damages and indicate that most dynamics are caused by recurring and spreading bark beetle infestation. The validation results based on field data confirm a high detection rate and show that the derived temporal information is reliable. In total, 23400 hectares, i.e., on average 2.8% of the forest area in the study area, are found to be affected by forest disturbance. The zonal statistic maps point out hotspots of significant forest disturbances, where adequate forest management measures are highly needed. Furthermore, this study highlights the TSA&#8217;s potential to also depict and monitor minor human impacts on forests, such as thinning, selective timber extraction or other moderate forest management practices.Keywords:&#160; forest disturbance; forest monitoring; bark beetle infestation; forest management; time series analysis; phenology modelling; remote sensing; satellite imagery; Sentinel-2

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Forest disturbances and the attribution derived from yearly Landsat time series over 1990–2020 in the Hengduan Mountains Region of Southwest China

Forest Ecosystems ◽

10.1186/s40663-021-00352-6 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Yating Li ◽

Zhenzi Wu ◽

Xiao Xu ◽

Hui Fan ◽

Xiaojia Tong ◽

...

Keyword(s):

Time Series ◽

Forest Management ◽

Biodiversity Conservation ◽

Forest Disturbance ◽

Road Construction ◽

Google Earth ◽

Forest Area ◽

Hengduan Mountains ◽

Natural Forests ◽

Forest Disturbances

Abstract Background Natural forests in the Hengduan Mountains Region (HDMR) have pivotal ecological functions and provide diverse ecosystem services. Capturing long-term forest disturbance and drivers at a regional scale is crucial for sustainable forest management and biodiversity conservation. Methods We used 30-m resolution Landsat time series images and the LandTrendr algorithm on the Google Earth Engine cloud platform to map forest disturbances at an annual time scale between 1990 and 2020 and attributed causal agents of forest disturbance, including fire, logging, road construction and insects, using disturbance properties and spectral and topographic variables in the random forest model. Results The conventional and area-adjusted overall accuracies (OAs) of the forest disturbance map were 92.3% and 97.70% ± 0.06%, respectively, and the OA of mapping disturbance agents was 85.80%. The estimated disturbed forest area totalled 3313.13 km2 (approximately 2.31% of the total forest area in 1990) from 1990 to 2020, with considerable interannual fluctuations and significant regional differences. The predominant disturbance agent was fire, which comprised approximately 83.33% of the forest area disturbance, followed by logging (12.2%), insects (2.4%) and road construction (2.0%). Massive forest disturbances occurred mainly before 2000, and the post-2000 annual disturbance area significantly dropped by 55% compared with the pre-2000 value. Conclusions This study provided spatially explicit and retrospective information on annual forest disturbance and associated agents in the HDMR. The findings suggest that China’s logging bans in natural forests combined with other forest sustainability programmes have effectively curbed forest disturbances in the HDMR, which has implications for enhancing future forest management and biodiversity conservation.

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Attitudes of coastal-forest users in Eastern Cape Province to management options arising from new South African forest policies

Environmental Conservation ◽

10.1017/s0376892902000371 ◽

2002 ◽

Vol 29 (4) ◽

pp. 519-529 ◽

Cited By ~ 12

Author(s):

John A.F. Obiri ◽

Michael J. Lawes

Keyword(s):

Forest Management ◽

Land Tenure ◽

Resource Use ◽

Local Communities ◽

The State ◽

Forest Resource ◽

Management Options ◽

Participatory Forest Management ◽

Management Policies ◽

Forest Users

New participatory forest management policies are being promoted in South Africa involving devolution from the state to local communities at a time when traditional authority has been eroded and is weak. Here, attitudes of forest stakeholders (forest resource users and managers) to three possible forest management policies, as well as to resource use, were investigated using questionnaires. There was concordance in the attitudes of resource users and managers and a general lack of support for community forest management (CFM), particularly among older resource users. Power shifts, uncertainty about land tenure and the management of what has essentially become an open-access system, all confound attempts to implement community-based forestry programmes. Local communities appeared to be wary of taking on responsibility for forest management at this time and indicated comparatively stronger support for state forest management (SFM). Forest stakeholders were more equivocal in their support for participatory forest management (PFM), although this probably reflects a poor understanding by forest users of the new PFM process. No stakeholders supported a total ban on forest resource use, but all supported controlled use. These latter attitudes were independent of the preferred management system (i.e. CFM, SFM or PFM). This study corroborates the view that CFM has been overemphasized. Rather than narrowing forest management around communities, but recognizing the state's incapacity to ensure the integrity of forest resources into the future without the co-operation of forest users, an all-inclusive approach, such as PFM, provides for greater management input by the state.

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CARACTERIZAÇÃO DO CONSUMO DE LENHA PELA ATIVIDADE DE CERÂMICA NO ESTADO DE SERGIPE

FLORESTA ◽

10.5380/rf.v40i3.18912 ◽

2010 ◽

Vol 40 (3) ◽

Cited By ~ 1

Author(s):

Meilani Fróes Machado ◽

Laura Jane Gomes ◽

Anabel Aparecida de Mello

Keyword(s):

Forest Management ◽

Tree Species ◽

Public Policies ◽

Forest Resources ◽

Fruit Tree ◽

The State ◽

Specific Consumption ◽

Forest Resource ◽

Fuel Material ◽

Structured Questionnaire

Os recursos florestais têm sido utilizados de forma indiscriminada no estado de Sergipe, principalmente pela retirada de madeira nas áreas de caatinga. Esse trabalho teve como objetivos conhecer o consumo e a procedência da lenha utilizada nas fábricas de cerâmica no estado de Sergipe, quantificar o consumo de lenha, caracterizar as fontes e as formas de fornecimento da lenha e calcular o consumo específico da lenha para a atividade. O estudo foi conduzido junto a nove empresas de cerâmica situadas nos municípios de Própria, Santana do São Francisco, Neópolis, Siriri e Capela, onde foi aplicado um questionário semi-estruturado. Os resultados obtidos demonstram que metade do material combustível utilizado pelas empresas é procedente de vegetação nativa da caatinga e de espécies exóticas frutíferas sem plantio de reposição. Sendo assim, é necessário um trabalho de sensibilização e implementação de políticas públicas junto aos ceramistas, com a finalidade de estabelecer formas sustentáveis de obter o material combustível.Palavras-chave: Recursos florestais; gestão florestal; dendroenergia. AbstractFirewood consumption in the ceramic activity in Sergipe State, Brazil. The forest resources have been indiscriminately used in the State of Sergipe, mainly because the wood harvested from the caatinga ecosystem. This work aimed to know the general consumption and the origin of the wood used in ceramic factories in the State of Sergipe. The main objectives were to quantify the consumption of firewood, characterize the sources and forms of supply, and calculate the specific consumption of firewood for the activity. The study was conducted in nine ceramic companies located in the Counties of Propriá, Santana do São Francisco, Neópolis, Siriri and Capela, where a semi-structured questionnaire was applied. The results showed that half of fuel material used by the companies came from the caatinga ecosystem and exotic fruit tree species. Therefore, a conscientiousness work is required, along with the implementation of public policies, in order to establish sustainable ways of obtaining the fuel material.Keywords: Forest resource; forest management; energy of firewood.

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Modification of a hierarchical model of forest disturbance

Environmental Conservation ◽

10.1017/s0376892998000022 ◽

1998 ◽

Vol 25 (1) ◽

pp. 3-7 ◽

Cited By ~ 3

Author(s):

JAMES F. TAULMAN

Keyword(s):

Forest Management ◽

Landscape Ecology ◽

Forest Disturbance ◽

Landscape Scale ◽

Reference Level ◽

Forest Disturbances ◽

Clear Cut ◽

Faunal Communities ◽

Landscape Scales ◽

Interesting Event

A model of disturbance equilibrationThe contemporary ‘non-equilibrium’ paradigm in ecology acknowledges that ecosystems and their component floral and faunal communities show historic dynamism, not unchanging constancy (Shugart & West 1981; Pickett et al. 1992; Hengeveld 1994). In formulating a hierarchical view of landscape ecology, Urban et al. (1987) modelled broad classes of forest disturbances and corresponding landscape scales. A reference level is the scale at which a disturbance is observed as an ‘interesting event’. At the next, lower landscape scale the disturbance has a significant impact and explanatory mechanisms may be investigated. At the level above the reference scale, the ‘event’ may be viewed in a broader ecological context where its impact has been buffered and successfully incorporated. Urban et al. (1987) suggested that ‘a disturbance regime that can be incorporated is not disturbing at all’. Extending this perspective to anthropogenic perturbations, Urban et al. (1987) praised the ‘wisdom’ of foresters for discovering clear-cut harvesting as a forest management strategy that mimics natural disturbances. It might be possible for a reader with a pro-exploitation agenda to misinterpret the meaning of the model presented in Urban et al. (1987) and attempt to use it in support of forest management that is destructive to overall ecosystem health, thereby detracting from Urban et al.'s (1987) and Shugart and West's (1981) pioneering contributions to the field of landscape ecology. It could be argued that we only need look to a higher landscape scale in the model of equilibration to find a level at which clear-cuts need no longer be considered forest disturbances.

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TRADITIONAL AND MODERN METHODS OF SATELLITE IMAGES PROCESSING FOR OPERATIONAL MAPPING OF FOREST COVER DISTUBANCES

Vestnik SSUGT (Siberian State University of Geosystems and Technologies) ◽

10.33764/2411-1759-2020-25-3-201-213 ◽

2020 ◽

Vol 25 (3) ◽

pp. 201-213

Author(s):

Andrey V. Tarasov ◽

Keyword(s):

Machine Learning ◽

Forest Management ◽

Forest Cover ◽

Forest Disturbance ◽

Remote Sensing Data ◽

Machine Learning Algorithms ◽

Forest Disturbances ◽

Detection Algorithms ◽

Vegetation Indexes ◽

Images Processing

Real-time mapping of forest disturbances is important for forest management. Detection of forest stands damaged by natural or human-induced factors allows making immediate necessary management decisions. To implement such a management strategy, it is necessary to use the methods of operational mapping. With the advent of the Earth remote sensing data (RSD), which have high spatial and temporal resolution (Planet Scope and Sentinel-2), it becomes possible to implement modern operational mapping methods for forest management operations (particularly, forest disturbance detection). Since the monitoring area and the number of images sharply increases, the need for automated image processing methods also rises. This paper provides an overview of “traditional methods” for identifying forest cover disturbances (vegetation indexes, Tasseled Cap, multiband and single band change detection etc), their basis, limitations, and experience of their application in Russia and in the world. Instead, algorithm based on machine learning methods and their classification are presented. Benefits and limitations of both groups of forest disturbances detection algorithms are noted. In addition, it was found out that there is limited experience of application of machine learning algorithms for RSD processing and such kind of research is relevant.

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ON FOREST ECONOMICS TRANSFORMATION

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2019/3/8-11 ◽

1970 ◽

pp. 8-11

Author(s):

А. Kh. Chochaev

Keyword(s):

Forest Management ◽

Market Economy ◽

Atmospheric Precipitation ◽

The State ◽

Forest Economics ◽

Environmental Consequences ◽

Social Environmental ◽

Groundwater Reserves ◽

Growing Conditions ◽

Environmentally Sound

The article analyzes problems of the Russia forest complex development related to social, environmental and infrastructure issues, the solution of which is impossible without state participation. The reasons of the poor adaptation of the forest complex market economy to long development periods, as well as the environmental consequences of economic activity, including environmental pollution, depletion of natural resources, loss of biodiversity and damage to public health, are considered. The analysis of the forest complex market economy features is made on domestic and foreign examples, a serious shortcoming of which is the isolation of the investment payback process from the chosen economic development direction. Forest rejuvenation in this way leads to a decrease or even loss of the forests biospheric properties to regulate the surface runoff of atmospheric precipitation and the formation of groundwater reserves. It is known, that in the forests of the European part of Russia have been accumulated large reserves of semi-subsistence conifer and hard wood. It is shown that to involve it in use it is necessary to change the principles of annual use calculations and to actually re-develop the regulatory framework for the intermediate use of forest wood resources. Four forest management units in the forest economy of the forest complex were identified: state forest management and implementation of medium-term and long-term planning of all types of work in forests, taking into account materials of the state forest inventory and assessing the state and trends in the development of domestic and foreign timber markets; protection and protection of forests from fires and other adverse natural factors (insects, fungi, pollution); carrying out planned logging with the differentiated use of all types of wood and the organization of reforestation taking into account the diversity of growing conditions and the possibilities of using the lands of the state forest fund of Russia. It is advisable to create economic mechanisms to stimulate the activities of all enterprises and institutions of the Russia forest complex for the transition to new environmentally sound technologies in the forest. A flexible economic mechanism is needed to include forest management costs in the cost of harvested wood in order to restore the ecological, economic, social and cultural properties of forests.

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Das waldreiche obere Theresiental (Transkarpatien, Ukraine) – geografisch-ökologische und sozioökonomische Beschreibung | The forest-rich upper Theresian Valley (Transcarpathia, Ukraine): a geographic-ecological and socio-economical description

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2007.0014 ◽

2007 ◽

Vol 158 (1-2) ◽

pp. 14-21

Author(s):

Vasyl Sabadosh ◽

Oleg Suprunenko

Keyword(s):

Forest Management ◽

High Water ◽

The State ◽

Water Levels ◽

Private Companies ◽

Foreign Investors ◽

Wood Processing ◽

Job Opportunities ◽

Orange Revolution

The upper Theresian Valley lies along the southwest-facing ridge of the Ukrainian Carpathians. Despite expansive forestation high water levels are frequent. The forest belongs to the state and is centrally administrated. Felling is sometimes outsourced to private companies and private companies have also been founded to process the timber. Job opportunities have become fewer and illegal work is increasing. A new democratic awareness has emerged since the «Orange Revolution» in 2004. With foreign investors, however, new risks emerge. The authors recommend giving monies from forest management to the communities, the founding of new wood processing enterprises and more transparent information.

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La systémique: son apport à la sylviculture et son rapport au marché | Systemics: its contribution to silviculture and its connection to the market

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2006.0283 ◽

2006 ◽

Vol 157 (7) ◽

pp. 283-286

Author(s):

Guido Bernasconi

Keyword(s):

Forest Management ◽

Public Funding ◽

Management Plan ◽

Living System ◽

The State ◽

The Body ◽

Systemic Approach ◽

Forest Management Plan

The silvicultural principles of a forest management plan for Canton Neuchâtel reveals itself as steeped in a systemic approach that allows us to consider the forest as a truly living system. In this context, it seems judicious to the author to conceive of the body forest personnel as a group of responsible people who share certain common ethics and who, in their work, promote the emergence of collective services recognised as beneficial to the state and which would be supported by public funding for the good of the entire community.

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PHENYLKETONURIA, AND GUTHRIE INHIBITION ASSAY SCREENING PROCEDURE

PEDIATRICS ◽

10.1542/peds.32.3.344 ◽

1963 ◽

Vol 32 (3) ◽

pp. 344-346

Keyword(s):

Public Health ◽

Large Scale ◽

Human Genetics ◽

Screening Program ◽

Genetic Diseases ◽

State Department ◽

The State ◽

Detection Methods ◽

Inhibition Assay ◽

Pilot Studies

Recommendations were made in view of the following facts: (1) the need for further information on the mechanisms involved in the phenotypic expressions of phenylketonuria; (2) the present lack of adequate data on the effectiveness of the Guthrie Inhibition Assay, in terms of number of cases which may be missed, factors making for positive determinations and providing other information on which to evaluate the appropriateness of the large-scale screening program proposed; (3) the undesirability of deploying inordinate resources in the evaluation of the Guthrie Inhibition Assay to the detriment of the needs of other areas of child health including phenylketonuria; (4) the indications that a multi-faceted approach to phenylketonuria would be productive, not only in resolving the problems involving this disorder but also as a model for the investigation of and application to the treatment of other genetic diseases; (5) the possibility that the Guthrie Inhibition Assay could be a useful tool in the early detection, treatment and investigation of phenylketonuria; and (6) the fact that other state health departments are participating in the Guthrie Field Trials, indicating that the California State Department of Public Health should apply its resources to a more intensive study of PKU and detection methods. The consultants made the following recommendations, through resolution, to the California State Department of Public Health. It was resolved that: 1. The State of California not be responsible at this time for initiating or recommending that the Guthrie procedure be accomplished on a state-wide basis in all newborn nurseries (one dissent). 2. The State of California initiate and coordinate the development of pilot studies in selected hospitals and medical centers throughout the State in the investigation of phenylketonuria, utilizing the Guthrie Inhibition Assay or other tests. 3. A scientific committee be appointed immediately as an advisory committee to the State Department of Public Health to develop recommendations for carrying out the suggested investigations. 4. A registry for phenylketonuria and other diseases (as listed in the recommendations by the Subcommittee on Human Genetics) be established within the framework of the State organization.

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