Spatial analysis techniques for ensuring the compatibility of land management activities and aquatic habitat quality in eastern Oregon

A land management scheduling model is developed that uses a Tabu search procedure to schedule timber harvests and road management activities, while simultaneously meeting (over time and space) two aquatic goals, and also providing for an even-flow of timber harvest volume. Decision variables include land units and roads, and they are considered to take on integer (0-1) solutions. Decision choices include those that involve land allocation issues (harvest and road obliteration), and those that involve changes in management practices (using lower tire pressures on certain roads to reduce the amount of sediment produced). The scheduling model included provisions for estimating stream sediment and temperature impacts as a result of the spatial location of management activities, and provisions for projecting the growth and yield of timber stands over time using growth rates derived from yield tables. The model uses Tabu search procedures to guide the selection of land management activities, and was applied to a 14,643 acre case study watershed in eastern Oregon. Twenty independent solutions were generated, of which 80 percent were within 10 percent of an estimated global optimum net present value, and all were within 15 percent. Although the limitation to using Tabu search is that one is not assured of obtaining the global optimum solution to a particular problem, the model developed here is an important contribution to forest planning for problems which have 100,000+ integer variables and spatial goals. An analysis of model results showed significant negative correlation between equivalent clearcut acres (ECA), a commonly used measure of cumulative watershed effects, and a stream temperature index. No correlation was observed between ECA, a stream sediment index, and timber harvest volume levels. These results suggest that sediment and temperature index levels may not be good proxies for ECA (or vice versa). Finally, the sensitivity of model results was examined using three different representations of the landscape: (a) vegetation units, (b) soils units, and (c) a combination of vegetation and soils units. Results show significant differences exist in terms of net present value, length of road assigned to central tire inflation use per period, stream sediment and temperature indices, ECA, and timber harvest volume levels

Back to the Future Part 2: Surveying Geospatial Technology Needs of Georgia Agriculture and Natural Resources Extension Professionals

Land conversion and habitat fragmentation are affecting natural resources. Land use/land cover change models can play an important role in understanding these impacts and illustrating the land conversion process to the public. A two-phase needs assessment was conducted to understand the perspectives, attitudes, and needs of planning and education officials. The second phase targeted Extension professionals in Georgia. The majority of Extension professionals surveyed felt that land use/land cover change projections would be valuable in their extension efforts. They felt that projections would be best distributed via Web-based access to maps and through research centers or workshops

Evaluating the Accuracy of Remote Dendrometers in Tree Diameter Measurements at Breast Height

An accurate tree diameter (DBH) measurement is a significant component of forest inventory. This study assessed the reliability of remote dendrometers to measure tree DBH. We compared direct caliper measurements (reference measurements) to the remote measurements collected from a laser caliper and a smartphone at 0.5 m, 1 m, and 1.5 m distances from each tree within three forest types (pine, oak, and poplar forests). In general, all remote dendrometers underestimated the mean diameter compared to direct caliper measurements, regardless of forest types and distances. We observed that the mean deviation of direct caliper measurement and smartphone measurement at 1.5 m within a pine forest and oak forest were the lowest (0.3 cm and 0.36 cm, respectively). The deviations between direct caliper measurements and smartphone measurements at a 0.5 m distance, across forest types, were noticeably larger compared to others. An ANOVA test was used to determine whether significant deviations existed between caliper measurements and remote measurements at a specific distance, and among three different forest types. We rejected the null hypothesis, which suggested that there were no statistically significant differences (p<0.05) between tree DBH measurements obtained from the direct caliper measurements and indirect measurements (smartphone and laser caliper) captured at a distance. Then, a post-hoc test was performed to examine which set of estimated deviations was different from the reference data. The results suggested that indirect tree DBH measurements using the smartphone app at 1 m and 1.5 m in certain forest types (pine and oak) were not significantly different from direct tree DBH measurements. Also, our test results mostly indicated no significant difference within each forest, except for measurements using the smartphone app at 0.5 m across all forest types when the smartphone measurements were compared to laser caliper measurements..

Synthesis of Knowledge of Hazardous Fuels Management in Loblolly Pine Forests

This synthesis provides an overview of hazardous fuels management in loblolly pine (Pinus taeda) forests, as well as a reference guide on prescribed burning and alternative fuel management treatments. Available information is presented on treatment feasibility, approximate costs, and effects on soil, water quality, and wildlife. The objectives of fuel management in loblolly pine forests are to reduce the density of some targeted plant vegetation and change the structural condition of the forest, or both. Prescribed burning is the most common tool for managing fuels in the South due to the relatively low cost per acre and the ability to reduce fuel levels rather than rearrange them. Mechanical treatments may be effective in reducing wildfire risk by redistributing the fuels closer to the ground, creating a more compact fuel bed. Mulching (mastication) and chipping are the only common mechanical treatments in the Southern United States and generally are used as precursors to prescribed burning. The limited use of mechanical treatments is due to the rapid redevelopment of live fuels and higher treatment costs than prescribed burning. Herbicide treatments for hazardous fuels management are a realistic option in certain situations. Although herbicides cannot replace prescribed burning or mechanical operations where dead fuels must be removed or repositioned closer to the ground, they are useful as preliminary treatments to kill or suppress live fuels or following a prescribed burn or mechanical operation to kill resprouting woody species. Although livestock grazing is no longer common in southern forests, grazing can be used to reduce certain types of live fuels. For example, sheep grazing has been used in Florida to control saw palmetto (Serenoa repens). Wider impacts of fuel treatments are discussed for several social and ecological factors, such as soil erosion, water quality, wildlife, and public acceptability

Decision support approaches in adaptive forest management

Climate and social changes place strong demands on forest managers. Forest managers need powerful approaches and tools, which could help them to be able to react to the rapidly changing conditions. However, the complexity of quantifying forest ecosystems services as well as the complexity of current decision theories, technologies and operation research methods, complicate the creation of one general tool. The continuous research and development in this area is an indispensable part of the success of adaptive management as well as the sharing of knowledge and information between research teams around the world. The Community of Practice of Forest Management Decision Support Systems provides a platform for broad discussion among scientists, researchers as well as forest professionals. This special issue provides papers which resulted from a conference session of the International Union of Forest Research Organizations’ (IUFRO) 125th Anniversary Congress in Freiburg, Germany in 2017. The joint sessions and other meetings (and resulting publications) are appropriate opportunities for knowledge sharing on these important methods and systems for protecting and managing forest ecosystems in the future.This special issue was supported by the project “Advanced research supporting the forestry and wood-processing sector’s adaptation to global change and the 4th industrial revolution”, reg. No. CZ.02.1.01/0.0/0.0/16_019/0000803

Search reversion within s-metaheuristics: impacts illustrated with a forest planning problem

The use of a reversion technique during the search process of s-metaheuristics has received little attention with respect to forest management and planning problems. Reversion involves the interruption of the sequence of events that are used to explore the solution space and the re-initiation of the search process from a high-quality, known starting point. We explored four reversion rates when applied to three different types of s-metaheuristics that have previously shown promise for the forest planning problem explored, threshold accepting, tabu search, and the raindrop method. For two of the s-metaheuristics, we also explored three types of decision choices, a change to the harvest timing of a single management unit (1-opt move), the swapping of two management unit's harvest timing (2-opt moves), and the swapping of three management unit's harvest timing (3-opt moves). One hundred independent forest plans were developed for each of the metaheuristic / reversion rate combinations, all beginning with randomly-generated feasible starting solutions. We found that (a) reversion does improve the quality of the solutions generated, and (b) the rate of reversion is an important factor that can affect solution quality.Keywords: forest planning, threshold accepting, heuristics, tabu search, patial harvest scheduling, mixed integer goal programming, adjacency constraint

Recreation Potential Assessment at Tamarix Forest Reserves: A Method Based on Multicriteria Evaluation Approach and Landscape Metrics

The purpose of this study was to develop new methods to describe outdoor recreation potential based on landscape indicators and systemic multicriteria evolution in the Tamarix forest reserves of Varamin city, a part of Iranian–Turanian forests of the Tehran province in Iran. First, in conducting a multicriteria evaluation, ecological factors that included slope, aspect, elevation, vegetation density, precipitation, temperature, and soil texture were mapped, classified, and coded according to the degree of desirability for outdoor recreation. All these maps were then intersected and the final map of recreational potential for three regions of the forest reserves was prepared. Results showed that the Shokrabad region had more recreation potential than the other two regions (Fakhrabad and Dolatabad) in terms of the sum of ecological factors potentially affecting tourism potential. Second, in conducting a landscape-based method, six of the most important indicators of the landscape that are effective in outdoor recreational potential were developed for each region. The combination of these landscape features determined the value of a place for recreational activities from a landscape perspective. The results showed that a large part of the Shokrabad region and a smaller number of places in the Fakhrabad and Dolatabad regions have high outdoor recreational potential. The area suitable for recreation in the output of the multicriteria evaluation method turned out to be greater than the area suggested by the landscape method, as more factors were examined in the multicriteria evaluation method. Of the set investigated, the topography and soil factors played an important role in the evaluation

Landscape Management Policy Simulator (LAMPS) : version 1.1 : user guide

The LAndscape Management Policy Simulator (LAMPS) model, version 1.1, is a spatial simulation model developed to provide forest landscape planning simulations for the Coastal Landscape Analysis and Modeling Study (CLAMS). It is designed to help policymakers, managers, and planners think through alternative management scenarios and their potential effects on the ecological and economic resources of Oregon's Coast Range forests. LAMPS simulates changes to landscape structure over time, incorporating the management intentions of the four major landowner groups and vegetation dynamics. Socioeconomic and ecological information is used to track and allocate activities across the landscape. LAMPS projects, with relatively high resolution, forest conditions across broad areas, all ownership groups, and a planning horizon of 100 yr. This user guide provides instructions on how to use LAMPS for forest landscape simulations of alternative forest policies for the Coast Range of Oregon

Assessing the Accuracy of Tree Diameter Measurements Collected at a Distance

The ability to measure trees remotely or at a distance may be of value to forest inventory processes. Within three forest types (young coniferous, old coniferous, and deciduous), we compared laser caliper measurements collected at distances up to 12 m from each tree, to direct contact caliper measurements. Bitterlich sector-fork measurements and diameter tape measurements were also collected for reference purposes. We used non-parametric tests to evaluate three of our four hypotheses that suggest there are no significant differences between direct and remote diameter measurements, between caliper measurements and sector-fork measurements, and between diameter measurement errors across forest types. In general, most of the differences in diameters were small (≤0.8 cm) and were observed within the 0–6 m measurement distance from each tree. These results suggest that forest characteristics and measurement distance may play a role in remote diameter measurement accuracy. We also performed a correlation analysis between light conditions and remote measurements. The correlation analysis suggested light conditions were not significantly correlated to diameter measurement accuracy