Pine Forest Types Research Articles

Study on the Speices Biodiversity of Plantation Communities in Primary Korean Pine Forest

Species diversity was refers to the rich and colorful differences between biological communities in composition, structure, function and dynamic. In this paper, the 64 pieces of plant community samples as the foundation, From the different types and levels of richness and evenness and species diversity index of Liangshui Nature Reserve, three original Korean pine forest types: korean spruce-korean pine forest (HY); oak-korean pine forest (HZ); linden-korean pine forest (HD), two adjacent artificial forest types: birch pure forest (BH); larch pure forest (LY) studied, conclusions were as follows: vegetation community structure features survey were conducted to identificate 39 species of vasculat plant through analying community species composition which belonging to 32 genera of 22 families. The community species structure was analyed to find that Korean spruce–korean pine community and larch pure community were stable structure; oak-korean pine community was ageing structure. linden-korean pine community and birch pure community were growing structure. The Korean pine forest species richness and evenness no significant difference with artificial forests, species diversity indexes were significantly higher compared with the artificial forests, plant communities less be disturbed, community stability higher than artificial forests.

Forest developmental trajectories in mountain pine beetle disturbed forests of Rocky Mountain National Park, Colorado

A mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic has caused widespread mortality of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) trees across western North America,. We characterized the initial effects of beetle-induced mortality on forest structure and composition in Rocky Mountain National Park, Colorado. In 2008, we surveyed stand structure and tree species composition across lodgepole pine dominated forests in the western portion of the Park. We defined five lodgepole pine forest types to describe variability in pre-epidemic forest conditions. This forested landscape appears to be resilient to the effects of the beetle. Surviving trees, including both canopy trees and saplings, were plentiful in most of the post-epidemic forests, even after accounting for anticipated future mortality. Subalpine fir (Abies lasiocarpa (Hook.) Nutt.), Engelmann spruce (Picea engelmannii Parry ex Engelm.), and aspen (Populus tremuloides Michx.) had modestly higher relative abundances after the epidemic. Lodgepole pine remained the dominant species on approximately 85% of the landscape. The impact of the outbreak on forest structure and composition varied considerably among the five forest types, suggesting that post-epidemic forest developmental trajectories will vary according to pre-outbreak stand characteristics. Active management efforts to regenerate lodgepole pine forests, e.g., tree planting, will likely not be necessary on this landscape.

Multiscale Habitat Selection and Refuge Use of Common Kingsnakes, Lampropeltis getula, in Southwestern Georgia

Abstract The Common Kingsnake, Lampropeltis getula, is thought to be experiencing population declines in the southeastern portion of its geographic range. However, limited information exists regarding the natural history and habitat requirements of the species in this region. We conducted a radio-telemetry study to investigate habitat selection in L. getula at multiple scales in southwestern Georgia. At the home range scale, L. getula did not show habitat selection. However, at the study-area scale, L. getula selected for natural pine and hardwood forest types over other available habitats. At the microhabitat scale, L. getula were found in locations with more coarse woody debris and woody vegetation than random sites. Lampropeltis getula primarily used small mammal (Peromyscus spp.) burrows and stumpholes as below ground refuge sites. We demonstrate that habitat selection of L. getula is complex and occurs at multiple scales.

Modeling soil respiration based on carbon, nitrogen, and root mass across diverse Great Lake forests

The variability in the net ecosystem exchange of carbon (NEE) is a major source of uncertainty in quantifying global carbon budget and atmospheric CO 2. Soil respiration, which is a large component of NEE, could be strongly influential to NEE variability. Vegetation type, landscape position, and site history can influence soil properties and therefore drive the microbial and root production of soil CO 2. This study measured soil respiration and soil chemical, biological and physical properties on various types of temperate forest stands in Northern Wisconsin (USA), which included ash elm, aspen, northern hardwood, red pine forest types, clear-cuts, and wetland edges. Soil respiration at each of the 19 locations was measured six times during 1 year from early June to mid-November. These data were combined with two additional data sets from the same landscape that represent two smaller spatial scales. Large spatial variation of soil respiration occurred within and among each forest type, which appeared to be from differences in soil moisture, root mass and the ratio of soil carbon to soil nitrogen (C:N). A soil climate driven model was developed that contained quadratic functions for root mass and the ratio of soil carbon to soil nitrogen. The data from the large range of forest types and site conditions indicated that the range of root mass and C:N on the landscape was also large, and that trends between C:N, root mass, and soil respiration were not linear as previously reported, but rather curvilinear. It should be noted this function appeared to level off and decline at C:N larger than 25, approximately the value where microbial nitrogen immobilization limits free soil nitrogen. Weak but significant relationships between soil water and soil C:N, and between soil C:N and root mass were observed indicating an interrelatedness of (1) topographically induced hydrologic patterns and soil chemistry, and (2) soil chemistry and root production. Future models of soil respiration should address multiple spatial and temporal factors as well as their co-dependence.

Le pinete demaniali costiere di Ravenna e Ferrara: analisi dei tipi forestali e strutturali per la scelta del trattamento selvicolturale nel processo di pianificazione

The state-owned pine forests on the coast of Ravenna and Ferrara: analysis of forest and structure types for choice of silvicultural system in the planning process . Results of the analysis on typology and structure of state forests dominated by maritime pine (Pinus pinaster Ait.) are reported. These formations grow on a narrow coastal belt between Cervia (Ravenna) and Volano (Ferrara), in the Emilia-Romagna region (Italy). The aim of the study is to support the proper silvicultural system in order to satisfy multiple use of pine forests using the analysis of forest types and model types of structure. Main ecological and structural features of principal pine forest types and experimental criteria on silvicultural systems are explained.

How promptly nonindustrial private forest landowners regenerate their lands after harvest: a duration analysis

Understanding factors that influence how promptly landowners regenerate their timberlands after harvest, if at all, is critical to developing policies to improve forest productivity. Mississippi forest landowners with over 100 acres (1 acre = 0.404 ha) of forestland were surveyed in 2006 to collect harvest and regeneration data from 1996 to 2006. This study investigated the length of the time interval between harvest and reforestation. Nonparametric duration analysis was used to examine how long nonindustrial private forest landowners waited to reforest after harvesting. Parametric duration analysis was used to examine factors that influenced the length of this period. The mean time elapsed from harvest to regeneration was 11 months for landowners that regenerated their lands. The instantaneous probability of regeneration reached its highest value in the 16th month after harvest and, thereafter, decreased steadily until the 28th month, after which the probability of regeneration was essentially nil. Interest in timber production, employing a consultant, and ownerships that were predominantly pine forest types were factors associated with substantially shorter reforestation times. Lower stumpage prices and higher reforestation costs were associated with substantially longer reforestation times.

Timber product output implications of a program of mechanical fuel treatments applied on public timberland in the Western United States

This study reports the results from a 5 year simulation of forest thinning intended to reduce fire hazard on publicly managed lands in the western United States. A state simulation model of interrelated timber markets was used to evaluate the timber product outputs. Approximately 84 million acres (34 million hectares), or 66% of total timberland in the western United States, is publicly managed; of this 78 million acres (31.6 million hectares) are managed by the federal agencies. We considered three budget scenarios using a least-expensive highest-hazard area first policy. Our intention with this simulation is not to definitively answer questions about where or how to conduct treatments to reduce fire hazard on public lands but rather to begin to develop tools that can be used to inform such a policy debate. Considerable development of this tool is still needed before it will be useful for that purpose. Our initial simulations nonetheless provide insight into what might happen if available funds were allocated to the least-expensive highest-hazard areas across the west. Using assumptions of (1) an annual “subsidy” (payments for treatments), (2) the treatment costs, (3) the priority ranking by forest type, (4) fire hazard level, and (5) the wildland–urban interface (WUI) status, the simulation suggests that lodgepole pine ( Pinus contorta), ponderosa pine ( Pinus ponderosa), spruce ( Picea spp.)–fir ( Abies spp.) and Douglas-fir ( Pseudotsuga menziesii) are projected to be major forest types treated in the West. A combination of our treatment ranking assumptions and the low total treatable WUI acres on public timberland caused the model to concentrate almost exclusively on all the WUI stands and non-WUI ponderosa pine forest type at the budget of $150 million and $300 million. With the further increase of budget, a large proportion of treated acres are lodgepole pine and spruce–fir forest types using the thin-from-below approach. About 41% of the volume removals are sawtimber for all the public timberland treated under the low budget scenario ($150 million/year), 58 for moderate budget ($300 million/year), 50 for the high budget scenario ($1500 million/year). Under the moderate budget case ($300 million a year), about 19% of the total wood removed is projected to come from trees less than 5-inches (12.7 cm) in diameter at breast height (dbh), and another 16% of the biomass is expected from trees 20-inches (50.8 cm) dbh and above.

Comparison of reptile communities in three types of thermophilous Mediterranean forest in southern Greece

Reptile communities are compared in deciduous Valonia oak forests (Quercus aegilops L., 1753) and two types of pine forests (Pinus pinea L., 1753 and Pinus halepensis Mill., 1768) located at sea level in the northwestern Peloponnisos. In areas covered by homogenous forests, both species richness and diversity were higher in the oak forest stands. There is no significant difference in the diversity index between the two types of pine forest although P. pinea stands had higher species richness. The diversity index takes the higher values in the transition zones of all types of forests, mainly due to the heterogeneity of those habitats. The oak forest and its respective transition zone had the most distinctive species composition in comparison to all other habitats, characterised by high densities of diurnal heliothermic lizards. The results reveal that even small‐sized broadleaved stands in conifer forests can significantly contribute to conserve reptile diversity. From a conservation point of view, the expansion of P. halepensis during the last decades decreases the heterogeneity of space leading to a decline in diversity.

Climate effects on historical fires (1630 - 1900) in Utah

We inferred climate effects on fire occurrence from 1630 to 1900 for a new set of crossdated fire-scar chronologies from 18 forested sites in Utah and one site in eastern Nevada. Years with regionally synchronous fires (31 years with fire at ≥20% of sites) occurred during drier than average summers and years with no fires at any site (100 years) were wetter than average. Antecedent wet summers were associated with regional-fire years in mixed-conifer and ponderosa pine forest types, possibly by affecting fine fuel amount and continuity. NINO3 (an index of the El Niño–Southern Oscillation, ENSO) was significantly low during regional-fire years (La Niñas) and significantly high during non-fire years (El Niños). NINO3 also was high during years before regional-fire years. Although regional fire years occurred nearly twice as often as expected when NINO3 and the Pacific Decadal Oscillation were both in their cool (negative) phases, this pattern was not statistically significant. Palmer Drought Severity Index was important for fire occurrence in ponderosa pine and mixed-conifer forests across the study area but ENSO forcing was seen only in south-eastern sites. Results support findings from previous fire and climate studies, including a possible geographic pivot point in Pacific basin teleconnections at ~40°N.

INFLUENCES OF SECONDARY DISTURBANCES ON LODGEPOLE PINE STAND DEVELOPMENT IN ROCKY MOUNTAIN NATIONAL PARK

Although high-severity fire is the primary type of disturbance shaping the structure of lodgepole pine (Pinus contorta) stands in the southern Rocky Mountains, many post-fire stands are also affected by blowdown, low-severity surface fires, and/or outbreaks of mountain pine beetle (MPB; Dendroctonus ponderosae). The ecological effects of these secondary disturbances are poorly understood but are potentially important in the context of managing for ecological restoration and fire hazard mitigation. We investigated the effects of blowdown, surface fires, and MPB outbreaks on demographic processes in post-fire lodgepole pine stands in Rocky Mountain National Park, Colorado, USA. We used dendroecological methods to reconstruct stand characteristics prior to and following secondary disturbances for paired stands with and without secondary disturbances. Surface fire events do not kill canopy trees or trigger pulses of recruitment and as such do not have detectable influences on stand development. In contrast, both MPB and blowdown kill canopy trees and trigger pulses of tree regeneration of lodgepole pine and subalpine fir (Abies lasiocarpa). The amount and species composition of post-disturbance regeneration is dependent on the severity of the disturbance and on the time since stand initiation. Secondary disturbances of higher severity (i.e., killing >50% of the canopy trees) that occur in younger post-fire stands favor new establishment of lodgepole pine. In contrast, secondary disturbances of lower severity in older stands (>250 years) trigger a pulse of establishment of subalpine fir. The results of this study demonstrate that the high tree densities characteristic of lodgepole pine stands in the southern Rockies (southern Wyoming to northern New Mexico) are the result of dense regeneration following stand-replacing fires and that surface fires had little or no thinning effect on tree densities. Thus, current high stand densities in the study area are not the result of suppression of surface fires. Moreover, the strong pulses of regeneration following forest thinning by MPB and blowdowns imply that, depending on the degree of thinning, thinning prescriptions to reduce fuels in the lodgepole pine forest type may have the unintended consequence of increasing ladder fuels 15-20 years following treatments.

SELECTION OF DWARF MISTLETOE–INFECTED PONDEROSA PINES BY IPS SPECIES (COLEOPTERA: SCOLYTIDAE) IN NORTHERN ARIZONA

In 2002 a bark beetle epidemic severely impacted ponderosa pine (Pinus ponderosa Douglas ex C. Lawson.) forests in northern Arizona. Ponderosa pine mortality occurred over approximately 211,000 ha statewide (USDA 2002). Ips spp. (Ips pini Lecontei and I. lecontei Swaine, Coleoptera: Scolytidae) predominated within infestations and accounted for approximately 99% or about 208,000 infested hectares statewide (McMillin 2003, S.C. Kenaley personal communication). High rates of infestation and tree mortality occurred within the Coconino (24,400 ha), Prescott (30,600 ha), and Tonto National Forests (27,000 ha). In the Tonto National Forest alone, 47% of the ponderosa pine forest type was infested, and many stands had mortality rates of 80%‐90%. Western pine beetle (Dendroctonus brevicomis Leconte), roundheaded pine beetle (Dendroctonus adjunctunus Blandford), and mountain pine beetle (Dendroctonus ponderosae Hopkins) have also been detected within infested areas in northern Arizona, but these bark beetle populations have not yet reached epidemic levels. In many areas where bark beetle infestations occurred, ponderosa pine mortality was greatest in areas infested with southwestern dwarf mistletoe (Arceuthobium vaginatum

Forty Years and More Trees: Land Cover Change and Coffee Production in Honduras

Geographers interested in vegetation change increasingly focus on forest transitions. Several studies have documented an increase in forest cover in tropical America. This paper examines the nature of land cover change between 1954 and 1992 in a mountainous region of western Honduras. Analysis of aerial photographs indicates that tree cover increased by 17% around the town of Marcala. The accuracy of the aerial photograph analysis was assessed by field reconnaissance in 2004, which suggested that the increase in trees consisted largely of shade coffee fincas. More than 80% of the 46 field sites visited in this study experienced an increase in tree cover, which consisted of pine forest and several types of shaded tree canopies for the growth of coffee.

Fish and stream habitat risks from uncharacteristic wildfire: Observations from 17 years of fire-related disturbances on the Boise National Forest, Idaho

Several large, uncharacteristic wildfires occurred on the Boise National Forest in Southwest Idaho, from 1986 to 2003. From 1987 to 1994, severe wildfires burned almost 50% of the ponderosa pine forest types (about 200,000 ha). The intensity of the fires varied across the landscape, with a mix of low to moderate severity, and lesser amounts of high burn severity. After the fires, localized debris flows favored smaller order streams in watersheds less than 4000 ha in size, where there had been mostly high severity burning. Locally, areas experiencing high heat and post-fire debris flows had reduced fish numbers and altered fish habitats. Uncharacteristic wildfires on the managed portions of the Boise National Forest appeared to have more pronounced, short-term effects on fish habitats as compared with characteristic wildfires in the Central Idaho Wilderness. Even in the most severely impacted streams, habitat conditions and trout populations improved dramatically within 5–10 years. Post-fire floods apparently rejuvenated stream habitats by exporting fine sediments and by importing large amounts of gravel, cobble, woody debris, and nutrients, resulting in higher fish productivities than before the fire. These observations suggest that important elements of biodiversity and fish productivity may be influenced, or even created by fire-related disturbances. In some cases, habitats that were completely devoid of salmonid fishes just after the debris floods, were later re-colonized with migrants returning from downstream or nearby tributary rearing habitats. Re-population was likely enhanced by higher fecundity, homing instinct, and greater mobility of the larger migratory fish. Ecosystem restoration activities that reduce both short- and long-term threats of uncharacteristic wildfire on imperiled fishes could be emphasized in areas where local populations may be weak and/or isolated, but potentially recoverable. But forest ecosystem restoration alone may not reduce risks to fish if existing habitat conditions and isolation are limiting the population.

Repeatability and implementation of a forest vegetation indicator

Abstract The composition, diversity, and structure of vascular plants are important indicators of forest health. Changes in species diversity, structural diversity, and the abundance of non-native species are common national concerns, and are part of the international criteria for assessing sustainability of forestry practices. The vegetation indicator for the national Forest Inventory and Analysis (FIA) Program, USA, was designed to assess these issues. The objectives of this study were to: (1) assess the repeatability and practicality of the vegetation field techniques using independent measurements of 48 plots by two botanists and (2) examine the interpretation of forest health indicators from 2 years of data collected on 110 plots in the state of Oregon. Plant identification was similar for both botanists, with 80% of all plant species on the plot being identified to species, and another 14% identified to the genus level; the greatest problems were in dry forest types where plants had senesced by July. Agreement among botanists for species identification was 71% at the subplot level and 67% at the quadrat level, with many differences caused by plants being identified as closely related species, usually in the same genus. As a result, agreement between botanists on species richness and the abundance of non-native species was high, with correlation coefficients of 0.94 and 0.98, respectively. Quadrats detected only 20% of the species found from the subplot search, on average. Although botanists differed in their speed, 22% of subplot searches were completed within 15 min and 71% were completed within 30 min. Dramatic differences in patterns of plant diversity were found across the ecological regions of Oregon, with high plot richness and the highest species turnover among plots found in the Blue Mountains. Abundance of non-native species varied from 15% of the species in juniper (Juniperus occidentalis Hook.) stands to 1% in high-elevation conifer stands. The proportion of cover made up of non-native species was highest in juniper and Ponderosa pine (Pinus ponderosa P. & C. Lawson) forest types. Numbers of non-native species on a plot increased with the number of native species, but the relationship was weak (R2 = 0.09). Results suggest that the vegetation indicator provides a robust and valuable tool for assessing forest health.

Estimating fine-root biomass and production of boreal and cool temperate forests using aboveground measurements: A new approach

Information of fine-root biomass and production is critical for quantifying the productivity and carbon cycle of forest ecosystems, and yet our ability to obtain this information especially at a large spatial scale (e.g., regional to global) is extremely limited. Several studies attempted to relate fine-root biomass and production with various aboveground variables that can be measured more easily so that fine-root biomass and production could be estimated at a large spatial scale, but found the correlations were generally weak or non-existed at the stand level. In this study, we tested a new approach: instead of using the conventional way of analysing fine-root biomass at the stand level, we analysed fine-root data at the tree level. Fine-root biomass of overstory trees in stand was first separated from that of understory and standardized to a common fine-root definition of < 2 mm or < 5 mm diameter. Afterwards, we calculated fine-root biomass per tree for a ‘representative’ tree size of mean basal area for each stand. Statistically significant correlations between the fine-root biomass per tree and the diameter at the ground surface were found for all four boreal and cool temperate spruce, pine, fir and broadleaf forest types, and so allometric equations were developed for each group using a total of n = 212 measurements. The stand-level fine-root biomass of trees estimated using the allometric equations agrees well with the measurements, with r2 values of 0.64 and 0.57 (n = 171), respectively, for fine-roots < 2 mmand < 5 mm diameter. This study further estimated fine-root production as the product of fine-root turnover rate and fine-root biomass, and determined the turnover rate as a function of fine-root biomass, stand age, and mean annual temperature. The estimates of tree fine-root production agree well with reported values, with r2 value of 0.53 for < 2 mm and 0.54 for < 5 mm diameter (n = 162) at the stand level.

A preliminary assessment of the Montreal process indicators of air pollution for the United States.

Air pollutants pose a risk to forest health and vitality in the United States. Here we present the major findings from a national scale air pollution assessment that is part of the United States' 2003 Report on Sustainable Forests. We examine trends and the percent forest subjected to specific levels of ozone and wet deposition of sulfate, nitrate, and ammonium. Results are reported by Resource Planning Act (RPA) reporting region and integrated by forest type using multivariate clustering. Estimates of sulfate deposition for forested areas had decreasing trends (1994-2000) across RPA regions that were statistically significant for North and South RPA regions. Nitrate deposition rates were relatively constant for the 1994 to 2000 period, but the South RPA region had a statistically decreasing trend. The North and South RPA regions experienced the highest ammonium deposition rates and showed slightly decreasing trends. Ozone concentrations were highest in portions of the Pacific Coast RPA region and relatively high across much of the South RPA region. Both the South and Rocky Mountain RPA regions had an increasing trend in ozone exposure. Ozone-induced foliar injury to sensitive species was recorded in all regions except for the Rocky Mountain region. The multivariate analysis showed that the oak-hickory and loblolly-shortleaf pine forest types were generally exposed to more air pollution than other forest types, and the redwood, western white pine, and larch forest types were generally exposed to less. These findings offer a new approach to national air pollution assessments and are intended to help focus research and planning initiatives related to air pollution and forest health.

Developing a system of annual tree growth equations for the loblolly pine – shortleaf pine type in Louisiana

An individual tree growth modeling system was developed for the loblolly pine (Pinus taeda L.) – shortleaf pine (Pinus echinata Mill.) forest type in Louisiana using USDA Forest Service Forest Inventory and Analysis (FIA) data. In this study, the loblolly pine – shortleaf pine forest type was divided into three species groups: loblolly pine, other pines, and hardwoods. The growth system includes models for individual tree survival, diameter growth, height growth, and change in crown ratio for each of the three species groups. A multivariate extension of a two-step, model-based interpolation method is proposed to estimate parameters of annual tree growth equations based on measurements from 7-year growth periods. Results based on evaluation statistics such as mean difference, mean absolute difference, and fit index show that the two-step interpolation method is clearly superior to the averaging method, which is a typical linear interpolation method. The two-step method produced growth equations that project tree and plot attributes more accurately than the averaging method. Additionally, a Monte Carlo simulation analysis reveals that parameter estimates obtained from the two-step method are closer to the true parameter values than those from the averaging method. The approach described here should be useful for estimating parameters of other systems of annual tree growth equations from periodic measurements. Models such as the one presented here may be useful for projecting the characteristics of undisturbed forest inventory plots, e.g., FIA plots, and providing more up-to-date inventory estimates.

Aspects of biodiversity of Scots pine forests in Europe

Management of Scots pine, the most widely distributed conifer in the world, was often based on clearfelling and replanting regimes, resulting in a rather poor biodiversity value. However, there is nowadays a general expectation to increase biodiversity by applying a more complex silviculture. Although present knowledge of genetic factors is insufficient to draw firm conclusions on the desirable level of genetic diversity, it seems unlikely that current silvicultural practices will limit genetic diversity in Scots pine Native pinewoods are rare in Europe, but have a flora and fauna of high conservation value. Therefore they must be recognized as a priority habitat under the European Commission's Habitat Directive. The high conservation value of native stands is a function of their old-growth structure that provides a rare habitat. A number of measures should be taken in all types of Scots pine forests to enhance biodiversity. Firstly, old growth habitats should be promoted. Foresters have to accept that a small percentage of the pine resource should be managed upon much longer rotations. Secondly, retention of deadwood should be encouraged. Dead and dying wood are key components of stand structure and act as key substrates for many associated species, such as microbes, invertebrates, small mammals and birds. Furthermore, a complex stand structure should be promoted at both the horizontal and the vertical scale. A small scale forestry, group regeneration systems, natural regeneration, introduction of broadleaves and stronger thinnings are strongly recommended. Availability of quite precise niches significantly increases biodiversity value. Conservation of isolated populations, found under extreme environmental conditions, is an absolute need. Populations endangered either by their small size or by environmental stresses, hybridization with other species or human interference should be primarily conserved. Forest edges support a range of taxa, and open habitats can comprise many different plant community types. A large number of organisms are directly or indirectly dependent on or favoured by fire. However, enhancing biodiversity provokes also some risks. Generally, browsing is considered as a moderate risk. Introduced species, such as aspen, act as an alternate host to the rust. Open species can present a threat to the European pine marten, dying and deadwood can provide breeding habitats for pest species (Tomicus piniperda), burning increases the risk of seedlings being attacked pine fire fungus (Rhizina undulata) and forest edges may be an attractive habitat for pest insects. An extension of existing growth models is needed to incorporate biodiversity issues in forest management planning. Distance dependent individual tree growth models should be developed. Sets of indicators for biodiversity must integrate compositional, structural and functional attributes. Attributes such as species richness, species abundance, species diversity, horizontal and vertical distribution, tree age, tree size, stand diversity, architectural complexity, genetic variants and deadwood are needed for the establishment of biodiversity indices. Assessment of functional phenomena needs the knowledge of the driving biotic environmental factors.

Financial performance of mixed-age naturally regenerated loblolly-hardwood stands in the south central United States

To estimate the financial performance of a natural mixed species and mixed-age management in the loblolly-pine forest type, we examined 991 FIA plots in the south central states. The plots were of the loblolly pine forest type, mixed-age, and had been regenerated naturally. We gauged the financial performance of each plot from the equivalent annual income (EAI) produced by growth and harvest, between two successive inventories. The real price EAI (REAI) measured the financial performance based on the real price change, net of inflation, between surveys. The constant price EAI (CEAI) measured stand productivity at prices at the time of the first survey. Thus, the REAI is a measure of real economic performance, including timber growth and price changes. In contrast, the CEAI is a quantity index of timber growth, the growth of each product being weighted by its price. During the period 1977–1994, the main determinant of the REAI was the price change. Due to an overall favorable price trend, the mean REAI ($158 ha −1 year −1) was much greater than the mean CEAI ($24 ha −1 year −1). Due to increasing prices, the best performing plots had very high stocking levels. Thus, the best financial strategy was to hold the stock, making the opportunity cost of conservation negative. Instead, CEAI tended to be lower on stands with high basal area, and higher in stands with many trees, a low share of hardwoods, and many trees near sawtimber size.

Terrestrial Activity, Abundance and Species Richness of Amphibians in Managed Forests in South Carolina

We determined the relative abundance, days of surface activity and indices of species diversity, evenness and richness for amphibians inhabiting three differently managed forests surrounding a Carolina bay in South Carolina following restoration. We collected animals daily for 3 y (Oct. 1993–Sept. 1996) using drift fences with pitfall traps in three forest types: loblolly pine (Pinus taeda), slash pine (P. elliotti) and mixed hardwoods (predominantly oak, Quercus spp. and hickory, Carya spp.). Captured animals were marked and recaptures were recorded but not included in statistical analyses, except in our evaluation of activity. We compared results to those of a more limited study conducted before restoration.Amphibians were significantly more numerous and more active in the mixed hardwood forest than in the pine forest types. However, the hardwood forest had the lowest species diversity in 2 of the 3 y of the study. The slash pine habitat had the highest diversity in all 3 y and for the 3 y combined. Because the evenness index (J′) values differ in step with the species diversity index (H′) it appears that the evenness component of diversity, rather than the richness component, is what is determining H′ variation. A summer subset of these data and summer data from an earlier study of 1977–1978 is in marked contrast with yearlong patterns. For our summer data each forest type had the highest H′ value in one of the years of the study and again the J′ values parallel the differences in H′.Large numbers of southern toads (Bufo terrestris) reduced evenness, and therefore species diversity, for all three habitats particularly the mixed hardwoods where this species was especially abundant. Proportionally lower numbers of B. terrestris in the summer samples increased J′ and H′ indices. Overall lower abundance and H′ values in the summers of 1994–1996 compared with 1977–1978 may be the result of habitat alteration during the restoration of the Carolina bay.