Improving the integration of recreation management with management of other natural resources by applying concepts of scale from ecology.

In this article, we examine how issues of scale affect the integration of recreation management with the management of other natural resources on public lands. We present two theories used to address scale issues in ecology and explore how they can improve the two most widely applied recreation-planning frameworks. The theory of patch dynamics and hierarchy theory are applied to the recreation opportunity spectrum (ROS) and the limits of acceptable change (LAC) recreation-planning frameworks.

Virulence of Leptographium serpens on Longleaf Pine Seedlings Under Varying Soil Moisture Regimes.

Recently, Leptographium serpens has been recovered from the roots of declining and dead longleaf pine (Pinus palustris) in stands associated with various abiotic stresses. Although most data suggest that L. serpens is pathogenic to various Pinus spp.

An auxiliary method to reduce potential adverse impacts of projected land developments: subwatershed prioritization.

An index based method is developed that ranks the subwatersheds of a watershed based on their relative impacts on watershed response to anticipated land developments, and then applied to an urbanizing watershed in Eastern Pennsylvania. Simulations with a semi-distributed hydrologic model show that computed low- and high-flow frequencies at the main outlet increase significantly with the projected landscape changes in the watershed. The developed index is utilized to prioritize areas in the urbanizing watershed based on their contributions to alterations in the magnitude of selected flow characteristics at two spatial resolutions.

Population inertia and its sensitivity to changes in vital rates and population structure.

Because the (st)age structure of a population may rarely be stable, studies of transient population dynamics and population momentum are becoming ever more popular. Yet, studies of "population momentum" are restricted in the sense that they describe the inertia of population size resulting from a demographic transition to the stationary population growth rate. Although rarely mentioned, inertia in population size is a general phenomenon and can be produced by any demographic transition or perturbation.

Temporal patterns of foliar ozone symptoms on tall milkweed (Asclepias exaltata L.) in Great Smoky Mountains National Park.

Incidence and severity of ozone-induced foliar symptoms on tall milkweed (Asclepias exaltata L.) along selected trails in Great Smoky Mountains National Park (GRSM) were determined by two surveys/season conducted from 1992 through 1996. Overall incidence was 73%, and was 84%, 44%, 90%, 58%, and 82% for 1992-1996, respectively for the same clusters.

Influence of ozone pollution and climate variability on net primary productivity and carbon storage in China's grassland ecosystems from 1961 to 2000.

Our simulations with the Dynamic Land Ecosystem Model (DLEM) indicate that the combined effect of ozone, climate, carbon dioxide and land use have caused China's grasslands to act as a weak carbon sink during 1961-2000. This combined effect on national grassland net primary productivity (NPP) and carbon storage was small, but changes in annual NPP and total carbon storage across China's grasslands showed substantial spatial variation, with the maximum total carbon uptake reduction of more than 400gm(-2) in some places of northeastern China. The grasslands in the central northeastern China were more sensitive and vulnerable to elevated ozone pollution than other regions.

Impacts of climatic and atmospheric changes on carbon dynamics in the Great Smoky Mountains National Park.

We used the Dynamic Land Ecosystem Model (DLEM) to estimate carbon (C) storage and to analyze the impacts of environmental changes on C dynamics from 1971 to 2001 in Great Smoky Mountain National Park (GRSM). Our simulation results indicate that forests in GRSM have a C density as high as 15.9kgm(-2), about twice the regional average.

Use of ethylenediurea (EDU) to ameliorate ozone effects on purple coneflower (Echinacea purpurea).

Purple coneflower plants (Echinacea purpurea) were placed into open-top chambers (OTCs) for 6 and 12 weeks in 2003 and 2004, respectively, and exposed to charcoal-filtered air (CF) or twice-ambient (2x) ozone (O3) in 2003, and to CF, 2x or non-filtered (NF), ambient air in 2004. Plants were treated with ethylenediurea (EDU) weekly as a foliar spray. Foliar symptoms were observed in >95% of the plants in 2x-treated OTCs in both years.

Bi-parental cytoplasmic DNA inheritance in Wisteria (Fabaceae): evidence from a natural experiment.

Cytoplasmic inheritance was investigated in interspecific hybrids of Wisteria sinensis and W. floribunda. Species-specific nuclear, mitochondrial and plastid DNA markers were identified from wild-collected plants of each species in its native range.

Influence of irrigation and fertilization on transpiration and hydraulic properties of Populus deltoides.

Long-term hydraulic acclimation to resource availability was explored in 3-year-old Populus deltoides Bartr. ex Marsh. clones by examining transpiration, leaf-specific hydraulic conductance (G(L)), canopy stomatal conductance (G(S)) and leaf to sapwood area ratio (A(L):A(S)) in response to irrigation (13 and 551 mm year(-1) in addition to ambient precipitation) and fertilization (0 and 120 kg N ha(-1) year(-1)).

Predator functional response and prey survival: direct and indirect interactions affecting a marked prey population.

1. Predation plays an integral role in many community interactions, with the number of predators and the rate at which they consume prey (i.e.

Effect of land-cover change on terrestrial carbon dynamics in the southern United States.

Land-cover change has significant influence on carbon storage and fluxes in terrestrial ecosystems. The southern United States is thought to be the largest carbon sink across the conterminous United States. However, the spatial and temporary variability of carbon storage and fluxes due to land-cover change in the southern United States remains unclear.

Effects of sedimentation on soil nutrient dynamics in riparian forests.

The influence of sedimentation rates on biogeochemistry of riparian forests was studied near ephemeral streams at Fort Benning, GA. Upper reaches of seven ephemeral streams had received varying rates of sedimentation stemming from erosion along unpaved roadways at the military installation. Two reference catchments were also included in the study.

Ozone injury on cutleaf coneflower (Rudbeckia laciniata) and crown-beard (Verbesina occidentalis) in Great Smoky Mountains National Park.

Incidence and severity of visible foliar ozone injury on cutleaf coneflower (Rudbeckia laciniata L.) and crown-beard (Verbesina occidentalis Walt.) were determined along selected trails at three locations in Great Smoky Mountains National Park during the summers of 2000 and 2001: Clingmans Dome, Cherokee Orchard Road and Purchase Knob.

Pitch Canker Caused by Fusarium circinatum Identified on Spruce Pine in Alabama.

A dieback associated with resinous branch and main stem cankers was observed on two spruce pine (Pinus glabra Walt.) trees in Lee County, Alabama in July 2002. Xylem tissues beneath the cankers were resinsoaked as is characteristic of pitch canker on other southern pine species.

Influence of a drying cycle on post-drought xylem sap abscisic acid and stomatal responses in young temperate deciduous angiosperms.

•   Post-drought patterns of water relations and gas exchange were studied in relation to xylem sap abscisic acid (ABA) concentration during recovery for young plants of five woody species. The potential role of xylem sap [ABA] in these responses was the object of study. •   Potted plants were allowed to deplete soil water and then were rewatered.

Ozone impacts on loblolly pine (Pinus taeda L.) grown in a competitive environment.

One-year old, bare-root, loblolly pine (Pinus taeda L.) seedlings grown in an early successional plant community, were exposed to four ozone treatments, 12 h day(-1) (09:00-21:59 h CST), 7 day week(-1) in east-central Alabama for 2 years (1994-1995). Treatments included AA=ambient air (open plot; no chamber), CF = carbon-filtered air (approximately 0.

Production efficiency of loblolly pine and sweetgum in response to four years of intensive management.

We tested the hypothesis that productivity of intensively managed loblolly pine (Pinus taeda L.) and sweetgum (Liquidambar styraciflua L.) stands is dependent not only on leaf area, but also on foliar photosynthetic rate.

Air pollution: forest health and passive sampling.

32nd Annual Air Pollution Workshop Auburn University in Auburn, AL, USA, April 2000 Air pollution has profound effects on agriculture, forests and natural ecosystems. The first Air Pollution Workshop was held over 30 years ago, and the most vital issues have always been highlighted within this forum. This year, forest health and passive sampling of air pollutants were two key areas of interest.