查看更多>>摘要：A mail survey was conducted on nonindustrial private forest (NIPF) landowners' usage and assessment of services provided by assistance foresters in Alabama from 2000 to 2009. Overall, assistance foresters participated in 67% of all forest management activities. Consulting foresters provided nearly half (48%) of all the assistance. Industry foresters accounted for 17% of that assistance, in comparison with 22% in the 1990s. Public foresters provided most assistance services to landowners with low income and small acreage. The involvement of assistance foresters in management activities was correlated with landowner demographics and land characteristics, and the perception of assistance foresters was largely positive.
Stape, J. L.Albaugh, T. J.Blinn, C. E.Fox, T. R....
6页
查看更多>>摘要：Traditional methods (deciduous arborescent hardwood basal area, cover index) of quantifying competing vegetation were not well correlated with pine response to vegetation control in a regional study examining fertilizer and vegetation control response in Pinus taeda L. in the southeastern United States. Given the links between resource availability, leaf area index, and production in pine, we hypothesized that by quantifying the nitrogen used annually by competing deciduous arborescent hardwood vegetation to produce foliage we could predict pine plantation growth response to vegetation control at midrotation. We calculated annual nitrogen uptake of competing vegetation from leaf area index measured retrospectively with Landsat TM imagery, foliar nutrient concentration, and specific leaf area. Then, using a model that estimated pine production from annual nitrogen uptake, we estimated pine response to vegetation control based on the expected increase in pine productivity resulting from the additional nitrogen available after controlling the competing vegetation. The new method closely estimated (9 times) or underestimated (12 times) pine response for the 24 site and year combinations for which it was reasonable to make a comparison. We considered this result as providing support for our hypothesis. This approach should be applicable to managed pine plantations with deciduous arborescent hardwood competition at midrotation. Site-specific estimates of competing vegetation foliar nutrient concentrations and specific leaf area, along with a better understanding of nutrient uptake dynamics and fate of nutrients in the system, will improve model predictive ability.
Lyon, S. W.Quesada-Pineda, H.Smith, R. L.Kline, D. E....
6页
查看更多>>摘要：Central America may experience greater demand for international forest products in the future due to increasing population size, tourism, and deforestation. Plantations are the primary source of raw materials, yet plantations are being harvested and not adequately reforested. To meet future demand in Central America, a source of wood products may be necessary from other regions with an abundant supply of timber and a stable infrastructure, such as the Appalachian Region in the United States. A survey of Central American wood products retailers and manufacturers was conducted to identify market barriers for Appalachian wood products to the Central American market. Potential market opportunities for Appalachian forest product companies in Central America were evaluated and strategies were developed to increase exports from Appalachian wood products companies to these countries. The results indicated that Appalachian wood products may be suitable alternatives for wood products currently used in Central America because of similarities between products (e.g., color). The results suggest that Appalachian forest products companies may increase sales in Central America by partnering with local wholesalers, offering higher value-added products, maintaining similar pricing with competition, and offering sales and product discounts.
查看更多>>摘要：Field foresters have long required a method of accurate measurement of perimeter and area during forest management activities. Perimeter and area assessments that can be derived from individual waypoints collected via global positioning system (GPS) units can be an expensive endeavor. A question of concern for practicing foresters is as the cost of GPS units increase does the accuracy of waypoints and any derived perimeter and area assessments also increase? This research evaluated whether the dynamic collection of waypoints using consumer-grade GPS units ranging from $50 to $700 provide a sufficient level of accuracy for the calculation of perimeter and area under three types of canopy cover: a newly established 3-year-old pine plantation, a 13-year-old pine plantation nearing first thinning, and a 40-year-old mixed pine/hardwood stand. Perimeter and area accuracy was not related to cost indicating that inexpensive GPS units provide an accurate waypoint location when used to derive perimeter and area measurements. When compared to a professional survey of each cover type, the average perimeter root mean square error (RMSE) ranged from 18.72 ft (0.41% of total perimeter) in the 40-year-old mixed pine/hardwood stand to 108.50 ft (2.43% of total perimeter) in the 13-year-old pine plantation. The average area RMSE observed ranged from 0.07 acres (0.22% of total acreage) in the 3-year-old plantation to 1.32 acres (4.67% of total acreage) in the 13-year-old pine plantation. For many forestry applications needing a perimeter and acreage assessment, these levels of accuracy should be more than sufficient.
Zheng DaoLanHeath, L. S.Ducey, M. J.Smith, J. E....
10页
查看更多>>摘要：Quantifying forest carbon changes associated with growth and major disturbances is important for management of greenhouse gas emissions related to forests. Regional-level approaches with improved local growth data may refine estimates obtained using coarser resolution information. This study integrates remote-sensing-derived land cover change products, harvest data, forest fire data, and local forest growth estimates at the county level to identify forest ecosystem carbon change for the states of Oklahoma and Texas (1992-2006). Whereas Oklahoma was a carbon sink of 0.5 Tg C yr<sup>-1</sup>, Texas was estimated to be a carbon source of -1.8 Tg C yr<sup>-1</sup> for the period. The two states together functioned as a carbon source of -1.3 Tg C yr<sup>-1</sup> for the entire period, although it was a small sink of 0.1 Tg C yr<sup>-1</sup> in the recent period of 2001-2006 due to reduced annual rates of net forest-to-nonforest conversion and harvesting, compared to those in the early period of 1992-2001. Most counties located in the western portions of both states were small sinks of carbon during the period. Even though their growth rates are greater, many counties in the eastern portions of both states were carbon sources due to a higher intensity of forest-related disturbances. A sensitivity analysis was conducted to investigate possible double-counting of harvest and cover change by assuming half of the sequestration and emissions from land cover changes were already counted as harvest. Results indicated Oklahoma would be a sink of 1.0 Tg C yr<sup>-1</sup>, and Texas would be a small carbon source of -0.1 Tg C yr<sup>-1</sup>. Uncertainty in forest area for the western portions of these states remains an important source of potential error.
Lane, V. R.Miller, K. V.Castleberry, S. B.Miller, D. A....
7页
查看更多>>摘要：Small mammals are ecologically important and should be considered as part of the sustainable management of pine (Pinus spp.) plantations, a common forest type within the southeastern United States. Few studies, however, have described how combinations of mechanical and chemical site preparation and herbaceous weed control (HWC) used in pine plantations affect pocosin small mammal communities. For 6 or 7 years after site preparation depending on treatment, we examined small mammal responses to six treatments of increasing intensity via combinations of mechanical and chemical site preparation with HWC in six loblolly pine (Pinus taeda) plantations in the Coastal Plain of North Carolina. We removal trapped for 144,000 trap-nights and captured 3,795 small mammals during winter 2002-2006 and 2008. Pine management techniques had short-term (1-2-year) effects on small mammal captures, species richness, and diversity, although timing and magnitude varied by species. Small mammal parameters were greater in strip-shear plots than in chopped plots for 2 years after site preparation, less in plots receiving chemical site preparation than in plots without chemical site preparation for 1-2 years, and greater with banded than broadcast HWC for 1 year after application. It appears that pocosin small mammal communities are sustainable within intensively managed pine stands of the southeastern coastal plain.
NSTL
Soc Amer Foresters