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Since the mid-1970s, community ecology has undergone a slow shift away from a long preoccupation with questions of community equilibrium and stability. This shift has occurred not because these questions are unimportant; rather, it has occurred largely because current theory poses the questions too naively and in a manner that cannot be tested (Connell and Sousa 1983). Moreover, most ecologists now recognize that the stability and equilibrium status of ecological communities cannot be meaningfully discussed without reference to a defined spatial and temporal scale, because community change is inevitably continuous and scale dependent. No community of species achieves, let alone remains in, static equilibrium. Species continually wax and wane in relative abundance; they even go extinct locally and reimmigrate. These changes are due to exogenous (e.g., climatic, geological, and anthropogenic) forcing of the community and to endogenous ecological and evolutionary change. As with climate, the longer one monitors a com

The densely populated, forested landscapes of South Asia pose a particular challenge to an understanding of the dynamics of forest change. Of the six countries in this region, four – Bangladesh, Bhutan, India and Nepal – have experienced increases in forest area and/or in forest density, which cannot be directly attributed to commonly identified drivers of forest change, such as changes in population density, affluence, or development. A meta-analysis of 24 case studies finds that the dominant pathway to reforestation in South Asia appears to be that of protection and planting of trees in degraded forests. A second, commonly encountered pathway is farm agroforestry, leading to increased tree cover on privately owned lands. Reforestation on abandoned unproductive lands does not appear to be significant in South Asia. An in-depth study of four landscapes located in India and Nepal provides greater insight into the human drivers of reforestation and regrowth. Taken together, these analyses indicate that the commitment of national governments towards protection and the devolution of forest management to local communities have been critical in facilitating reforestation in this region.

"The effects of landscape changes caused by intensive logging on the availability of wild game are important when the harvest of wild game is a critical cultural practice, food source, and recreational activity. We assessed the influence of extensive industrial logging on the availability of wild game by drawing on local knowledge and ecological science to evaluate the relationship between forest change and opportunities to harvest Sitka black-tailed deer (Odocoileus hemionus sitkensis) on Prince of Wales Island, Alaska. We used data collected through interviews with local deer hunters and GIS analysis of land cover to determine relationships among landscape change, hunter access, and habitat for deer hunting over the last 50 yr. We then used these relationships to predict how harvest opportunities may change in the future. Intensive logging from 1950 into the 1990s provided better access to deer and habitat that facilitated deer hunting. However, successional changes in intensively logged forests in combination with a decline in current logging activity have reduced access to deer and increased undesirable habitat for deer hunting. In this new landscape, harvest opportunities in previously logged landscapes have declined, and hunters identify second-growth forest as one of the least popular habitats for hunting. Given the current state of the logging industry in Alaska, it is unlikely that the logging of the remaining old-growth forests or intensive management of second-growth forests will cause hunter opportunities to rebound to historic levels. Instead, hunter opportunities may continue to decline for at least another human generation, even if the long-term impacts of logging activity and deer harvest on deer numbers are minimal. Adapting hunting strategies to focus on naturally open habitats such as alpine and muskeg that are less influenced by external market forces may require considerably more hunting effort but provide the best option for sustaining deer hunting as a local tradition over the long run. We speculate that managing deer habitat in accessible areas may be more important than managing the overall health of deer populations on a regional scale. We further suggest that the level of access to preferred hunting habitat may be just as important as deer densities in determining hunter efficiency."

"Compensation to landowners for forest-derived environmental services has gained international recognition as a mechanism to combat forest loss and fragmentation. This approach is widely promoted, although there is little evidence demonstrating that environmental service payments encourage forest stewardship and conservation. Costa Rica provides a unique case study in which a 1996 Forestry Law initiated environmental service payments and prohibited forest conversion to other land uses. We examined these novel policies to determine their influence on landowner decisions that affect forest change, carbon services, and connectivity in a 2425 km2 biological corridor. We used Landsat images to compare land-cover changes before and after 1996, and linked these data to landowner surveys investigating land-use decisions. Carbon stocks and storage in secondary forests were also examined. Forest change observations were corroborated by landowner survey data, indicating that the 1996 Forestry Law and environmental service payments contributed positively to forest retention and recruitment. Socioeconomic conditions also favored forest protection. Rates of natural forest loss declined from -1.43% to -0.10%/yr after 1996. Forest cover and connectivity were maintained through tree plantations and secondary forest recruitment, although forest heterogeneity increased as these forest types sometimes replaced natural forest. Carbon storage in secondary forest approached levels in primary forest after 25-30 yr of succession, although few landowners retained natural regeneration. Secondary forests will persist as minor landscape components without legal or financial incentives. The Costa Rican experience provides evidence that environmental service payments can be effective in retaining natural forest and recruiting tree cover within biological corridors."

A common phenomenon in biological systems is for an environmental catastrophe to trigger population explosions by one or more rare species, causing them to burst into prominence, suddenly replacing populations that were dominant previously. A common mechanism is for a rare population to be suppressed by dominant populations until a cataclysm, such as a fire, a storm or a cometary impact triggers explosive growth. The example of forest change during the postglacial period is considered here in detail. Simulations show that dispersal across the landscape is important in the process: abrupt transitions and explosive growth occur only if dispersal distances are normally short.

In Algeria, arid and semi-arid regions occupy over than 95% of whole territory. Forests in the semi arid zone constitutes a front face to the advance of the desert towards northern sides. Like in other regions of the world, deforestation phenomenon have a serious consequences on the fragile ecosystem. Severe continuous drought, fires, pasture, insects as well as the absence of a clear forest politics are so many factors that reduced forest areas in this country. However, the conservation of this patrimony must be a priority of any regional development project. This paper describes an evaluating study of the deforestation impact on forests in the region of Djelfa situated in the Saharian Atlas using multitemporal satellite remote sensing data. In order to establish a forest change map, a methodology based on the comparison between normalized difference vegetation indexes (NDVI) generated from satellite images was adopted. For this purpose, a pair of Landsat ™ and (ETM+) images acquired over the region on April 11

This paper presents preliminary results of research to improve upon an existing operational forest change detection monitoring strategy in California. Comparisons were. made between Landsat 5 TM and Landsat 7 ETM scene normalization techniques (absolute versus, relative). Prior to normalization, scenes containing wildfire smoke plumes were successfully corrected using a space-varying haze equalization algorithm. Simple dark object subtraction provided improved performance over relative (pseudo-invariant feature) approaches. A decision tree classifier produced high change map overall accuracy (86%) for five categories of forest cover change.

The aim of the research described in this paper has been to develop change detection algorithms which would be suitable for an operational map update system. Two algorithms have been developed, one based on edge matching and another on object analysis. These algorithms have been tested on thematic mapper imagery, using ordnance survey (OS) and forestry commission (FC) digitized maps. When possible, knowledge of forest practice has been used to augment the results. Results indicate that, with minimal user interaction, major areas of change can be determined. Increasing user intervention can reduce algorithm complexity and processing time, at the expense of automation.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This study evaluates the potential of Landsat Multispectral Scanner (MSS) data to monitor long term changes in high-elevation coniferous forests. August 1973 and 1984 MSS data from the Green Mountains of Vermont were used. Following co-registration and standardization of data sets, colour density slices of 0.75 μm and 0·95 μm band difference images were produced. False colour composites using either (a) the 1973 0·65 μm and 0·75 μm band in conjunction with the 0.75 μm band difference data set or (b) the 1973 0·65 μm and 0·95 μm band in conjunction with the 0.95 μm band difference data set, were also produced. These images indicated that major reflectance decreases occurred for the near-infrared bands between 1973 and 1984 for much of the high-elevation forests. This includes the west-facing slope of Camels Hump, an area for which long term records documenting decreases in basal area and inferred biomass are available. It is believed that the reflectance decreases noted for the high-elevation coni...

SUMMARY Forest change can have a marked effect on water quality, water yield and storm-flow peaks with the magnitude of the effect depending on the specific site conditions. Water quality degrade can result from the removal of forest cover, soil disturbance, and the application of fertiliser, insecticides and herbicides. Steep slopes and poorly strucured shallow soils, either alone or in combination can increase the risk and extent of any degrade. Alterations in forest cover can result in marked changes in water yield and peak flow. Some forest changes, for example wildfire, can occur on a scale sufficient to assume immediate regional significance. Small scale forest changes can, if extended, build up over time until they are of regional significance, for example the destruction of jarrah forest by the cinnamon fungus or the conversion of dry sclerophyll forest to pine. Small community water supply systems with limited storage and treatment facilities are particularly sensitive to changes in the yield and...

In these analyses the author treats two peat samples (Jumoonjin and Bangeojin) and one boring core of alluvium (Pohang) from eastern coastal region of Korean Peninsula (Fig. 1, 6, 7, 8).The forest change in eastern coastal region, Korean Peninsula, since the Late Glacial Age is divided into two stages and three substages. It may be summarized as follows.I; Quercus Stage (10, 000-6, 000y. B. P.)II; Pinus-Quercus Stage (6, 000y. B. P. -present)IIa; Lower Pinus dominant Substage (6, 000-4, 000/3, 000 y. B. P.)IIb; Pinus, Quercus Substage (3, 000/4, 000-2, 000y. B. P.)IIc; Upper Pinus dominant Substage (2, 000y. B. P. -present)The change of the forest in study area was controlled mainly by climate, partly by sea level change and human activities.From forest change of Postglacial Age, the author considered that the Stage I and Substage II (b) were under relatively humid climate, but the Substage II (a) and II (c) were under relatively dry climate.

Simulations of cool-temperate forest growth in response to climatic change using the JABOWA computer model show that a decrease of 600 growing degree-days (equivalent to a 2°C decrease in mean annual temperature) causes red spruce (Picea rubens) to replace sugar maple (Acer saccharum) as the dominant tree. These changes are delayed 100–200 yr after the climatic cooling, producing gradual forest changes in response to abrupt temperature changes, and reducing the amplitude of response to brief climatic events. Soils and disturbances affect the speed and magnitude of forest response. The delayed responses are caused by the difference in sensitivity of adult trees and younger stages. The length of the delay depends on the life history characteristics of the dominant species. Delayed responses imply that fossil pollen deposits, even if they faithfully record the abundances of trees in forests, may not be able to resolve climatic changes within 100–200 yr, or to record very brief climatic events. This explains why pollen deposits do not as yet show responses to climatic changes during the past 100 yr. Only the Little Ice Age, which lasted several centuries, caused sufficient forest change to be recorded in fossil pollen, and only at certain sites.

Use of the LANDSAT MSS for forest inventory and regional management in Europe is reviewed on the basis of literature and the author's own experience. In Europe, the regional forestry application programs using LANDSAT MSS data have been characterized by a low degree of governmental support and a lack of coordination. The responsibility of introducing the LANDSAT technology to forestry community has been assumed by universities and research organizations. The University of Freiburg, the Technical Research Centre of Finland and the ITC in the Netherlands seem to be leading centers in the field. Research groups in Sweden, France, Italy and Switzerland have also contributed to the development of forestry applications. Two operational applications have emerged: annual monitoring of clear cut areas (Sweden, Finland) and forest site type mapping for forest taxation purposes (Finland). Those and other case studies under topics (1) Forest inventory, (2) Forest mapping, and (3) Forest change monitoring are reviewed...

This paper introduces a Special Issue of Forest Ecology and Management that includes a collection of analytical results from the 2015 Global Forest Resources Assessment (FRA 2015) covering 25 years of forest change (1990–2015). FRA 2015 builds on a series of global assessments that began in 1948 and covers change in forest area and type, volume, biomass and carbon stocking, measures of sustainable forest management, biodiversity and conservation, soil and water protective functions, wood production and a number of socio-economic variables. It covers 234 countries and territories with an emphasis on forest resource change over a twenty-five year period (1990–2015) and also looks forward to anticipated forest change – both as government targets for forest area and projected change (to 2030) to global production and conservation forest area (to the year 2050). This paper describes important contributions of global forest resource estimates to forest management, the methods used in the collection and analysis of FRA 2015 data and provides links to additional information resources. It discusses some of the limitations of this global dataset, some of the steps taken to improve quality and the characteristics that make this type of global data most useful. While forest area change dominates public use of the FRA, the state of the forest resource and management is critical to understanding the ecological and social values of the forest and forestry. Country level reporting not only provides insights that are only possible through national reporting but also provides greater national-level understanding and discussion of forest resource change. The papers that follow in this Special Issue provide analyses of FRA 2015 data covering a wide range of topics related to sustainable forest management and forest change.

Human activities have exerted a powerful influence on the biogeochemical cycles of nitrogen (N) and carbon (C) and drive changes that can be a challenge to predict given the influence of multiple e ...

Accurately mapping the spatial distribution of forests in sub-humid to semi-arid regions over time is important for forest management but a challenging task. Relatively large uncertainties still exist in the spatial distribution of forests and forest changes in the sub-humid and semi-arid regions. Numerous publications have used either optical or synthetic aperture radar (SAR) remote sensing imagery, but the resultant forest cover maps often have large errors. In this study, we propose a pixel- and rule-based algorithm to identify and map annual forests from 2007 to 2010 in Oklahoma, USA, a transitional region with various climates and landscapes, using the integration of the L-band Advanced Land Observation Satellite (ALOS) PALSAR Fine Beam Dual Polarization (FBD) mosaic dataset and Landsat images. The overall accuracy and Kappa coefficient of the PALSAR/Landsat forest map were about 88.2% and 0.75 in 2010, with the user and producer accuracy about 93.4% and 75.7%, based on the 3270 random ground plots collected in 2012 and 2013. Compared with the forest products from Japan Aerospace Exploration Agency (JAXA), National Land Cover Database (NLCD), Oklahoma Ecological Systems Map (OKESM) and Oklahoma Forest Resource Assessment (OKFRA), the PALSAR/Landsat forest map showed great improvement. The area of the PALSAR/Landsat forest was about 40,149 km2 in 2010, which was close to the area from OKFRA (40,468 km2), but much larger than those from JAXA (32,403 km2) and NLCD (37,628 km2). We analyzed annual forest cover dynamics, and the results show extensive forest cover loss (2761 km2, 6.9% of the total forest area in 2010) and gain (3630 km2, 9.0%) in southeast and central Oklahoma, and the total area of forests increased by 684 km2 from 2007 to 2010. This study clearly demonstrates the potential of data fusion between PALSAR and Landsat images for mapping annual forest cover dynamics in sub-humid to semi-arid regions, and the resultant forest maps would be helpful to forest management.

The use of satellite remote sensing in Malaysian forestry and its potential are discussed under three headings (1) Application of satellite remote sensing in Malaysian forestry; (2) Current efforts in remote sensing research application; (3) Potentials of remote sensing techniques in monitoring logging operations and forest change; and remote sensing as a tool in rehabilitation and reforestation. It is concluded that there is a high potential of satellite remote sensing application in Malaysia, especially with the Landsat and SPOT data supported with aerial photographs. This is due to its fast delivery of relevant, timely and accurate information needed for sustainable forestry and a sound management decision.

Airborne LiDAR data has become an important tool for both the scientific and industry based investigation of forest structure. The uses of discrete return observations have now reached a maturity level such that the operational use of this data is becoming increasingly common. However, due to the cost of data collection, temporal studies into forest change are often not feasible or completed at infrequent and at uneven intervals. To achieve high resolution temporal LiDAR surveys, this study has developed a micro-Unmanned Aerial Vehicle (UAV) equipped with a discrete return 4-layer LiDAR device and miniaturised positioning sensors. This UAV has been designed to be low-cost and to achieve maximum flying time. In order to achieve these objectives and overcome the accuracy restrictions presented by miniaturised sensors a novel processing strategy based on a Kalman smoother algorithm has been developed. This strategy includes the use of the structure from motion algorithm in estimating camera orientation, which is then used to restrain IMU drift. The feasibility of such a platform for monitoring forest change is shown by demonstrating that the pointing accuracy of this UAV LiDAR device is within the accuracy requirements set out by the Australian Intergovernmental Committee on Surveying and Mapping (ICSM) standards.