Ecosystem-based management for military training, biodiversity, carbon storage and climate resiliency on a complex coastal land/water-scape.

The Defense Coastal/Estuarine Research Program (DCERP) was a 10-year multi-investigator project funded by the Department of Defense to improve understanding of ecosystem processes and their interactions with natural and anthropogenic stressors at the Marine Corps Base Camp Lejeune (MCBCL) located in coastal North Carolina. The project was aimed at facilitating ecosystem-based management (EBM) at the MCBCL and other coastal military installations. Because of its scope, interdisciplinary character, and duration, DCERP embodied many of the opportunities and challenges associated with EBM, including the need for explicit goals, system models, long-term perspectives, systems complexity, change inevitability, consideration of humans as ecosystem components, and program adaptability and accountability. We describe key elements of this program, its contributions to coastal EBM, and its relevance as an exemplar of EBM.

The shrinking ark: patterns of large mammal extinctions in India.

Mammal extinctions are widespread globally, with South Asian species being most threatened. We examine local extinctions of 25 mammals in India. We use historical records to obtain a set of locations at which each species was known to have been present at some time in the last 200 years. We then use occupancy estimation models to draw inferences about current presence at these same locations based on field observations of local experts. We examine predictions about the influence of key factors such as protected areas, forest cover, elevation, human population density and cultural tolerance on species extinction. For all 25 species, estimated local extinction probabilities (referenced to a 100 year time frame) range between 0.14 and 0.96. Time elapsed since the historical occurrence record was an important determinant of extinction probability for 14 species. Protected areas are positively associated with lower extinction of 18 species, although many species occur outside them. We find evidence that higher proportion of forest cover is associated with lower extinction probabilities for seven species. However, for species that prefer open habitats (which have experienced intensive land-use change), forest cover alone appears insufficient to ensure persistence (the complement of extinction). We find that higher altitude is positively associated with lower extinction for eight species. Human population density is positively associated with extinction of 13 species. We find that 'culturally tolerated' species do exhibit higher persistence. Overall, large-bodied, rare and habitat specialist mammals tend to have higher extinction probabilities.

Reconstructing Holocene fire history in a southern Appalachian forest using soil charcoal.

Lacking long-term dendrochronological and lake sediment data, little is known regarding the history of fire in southern Appalachian forests through the Holocene. Here we used 82 radiocarbon ages for soil charcoal collected from local depositional sites along a topographic gradient from mixed hardwood (Liriodendron tulipifera and Quercus spp.) to oak-pine (Quercus prinus and Pinus rigida) forest to provide a coarse-grained picture of changes in fire frequency within a 10-ha area during the Holocene. Charcoal ages ranged from 0 to 10 570 yr BP, with a single date older than 4000 yr BP. The data indicate that fires occurred regularly across the study area over the past 4000 yr. Further, such fires were not confined to dry oak-pine dominated ridges, but extended downslope into areas that are today dominated by mesic hardwood forest. Summed probability analysis taking into account radiometric errors suggests that fires became more frequent approximately 1000 yr ago, coinciding with the appearance of Woodland Tradition Native Americans in this region. We provide a direct demonstration of relatively frequent fire at the forest stand scale in Appalachian forests over a significant portion of the Holocene. Our results are consistent with the widely held view that fires have become less frequent in this region over the past 250 years. We discuss the difficulties in calculating the inbuilt error associated with estimating actual fire dates from charcoal fragments. But we conclude that such analysis of soil charcoal is a promising approach for reconstructing general trends in fire behavior within forest stands in this region.

Fire and soil-plant nutrient relations in a pine-wiregrass savanna on the coastal plain of North Carolina.

Changes in soil and plant nutrient conditions were evaluated following various burn and clip treatments in a longleaf pine-wiregrass savanna in Bladen Co., N.C., USA. Ground fires were found to add substantial quantities of N, P, K, Ca, and Mg to the soil, though not necessarily in forms immediately available to plants. Less than 1% of the total nitrogen in the charred residue (ash) is present as nitrate or ammonium. Considerable quantities of all nutrients examined were lost to the atmosphere during burning. Green leaf tissue in recently burned areas was consistently higher in N, P, K, Ca, and Mg compared to unburned areas. Howerver, when compared to similar tissues from clipped plots, burned area tissues were significantly higher in N, Ca, and Mg only. Data presented here suggest that tissue age significantly affects nutrient content and must be considered in any analysis of tissue nutrient content following burning. Within 4-6 months following fire, burned-area tissue nutrient content decreases to concentrations found in the unburned area. Burning resulted in initial enrichment of available soil nutrients including PO4, K+, Ca++, and Mg++, however, NO3-, and NH4+ concentrations in burned soil were not significantly different from unbruned soil. Soil and plant nutrient changes in an area burned two years in succession indicate that repeated burning may diminish nutrient availability. Plant response to various nutrient enrichment treatments of the soil indicated that nitrogen is limiting growth in both burned and unburned soils and that burning may alter some factors other than nutrients which may retard plant growth in unburned areas.

Seasonal patterns of growth, tissue acid fluctuations, and 14CO2 uptake in the crassulacean acid metabolism epiphyte Tjllandsia usneoides L. (Spanish moss).

Seasonal patterns of growth, 14CO2 uptake, and fluctuations in tissue titratable acidity were studied over the course of a year at a study site in the coastal plain of North Carolina.Elongation rates of Spanish moss strands were maximal in the summer and minimal in the winter. Summer maximal biomass addition rates were calculated to be 3.4 mg·month-1. Mortality of the strands was greatest in the winter months. Rates of 14CO2 uptake and fluctuations in tissue acidity were greatest in the summer over a fairly broad spectrum of environmental conditions (day and night temperatures, irradiance, length of drought). Maximal 14CO2 uptake rates (1.2 mg CO2·mg Chl-1 ·h01) were measured in May 1978. Rates of 14CO2 uptake and fluctuations in titratable acidity were inhibited below 5°C and eliminated at 0°C air temperatures.Isothermal diurnal conditions resulted in low rates of 14CO2 uptake. Tissue water content did not appear to be a major factor controlling 14CO2 uptake rates. However, tissue wetting by rain severely reduced nighttime uptake yet stimulated low rates of daytime 14CO2 uptake. This was the only condition in which daytime 14CO2 uptake occurred, excluding the early morning and late afternoon 14CO2 uptake typical of many Crassulacean Acid Metabolism (CAM) plants.The results suggest that tissue water content is not the major factor controlling CO2 uptake as has been found in many other CAM species; and that low temperatures limit the growth of Spanish moss in North Carolina.

Reserves protect against deforestation fires in the Amazon.

BACKGROUND: Reserves are the principal means to conserve forests and biodiversity, but the question of whether reserves work is still debated. In the Amazon, fires are closely linked to deforestation, and thus can be used as a proxy for reserve effectiveness in protecting forest cover. We ask whether reserves in the Brazilian Amazon provide effective protection against deforestation and consequently fires, whether that protection is because of their location or their legal status, and whether some reserve types are more effective than others. METHODOLOGY/PRINCIPAL FINDINGS: Previous work has shown that most Amazonian fires occur close to roads and are more frequent in El Niño years. We quantified these relationships for reserves and unprotected areas by examining satellite-detected hot pixels regressed against road distance across the entire Brazilian Amazon and for a decade with 2 El Niño-related droughts. Deforestation fires, as measured by hot pixels, declined exponentially with increasing distance from roads in all areas. Fewer deforestation fires occurred within protected areas than outside and the difference between protected and unprotected areas was greatest near roads. Thus, reserves were especially effective at preventing these fires where they are known to be most likely to burn; but they did not provide absolute protection. Even within reserves, at a given distance from roads, there were more deforestation fires in regions with high human impact than in those with low impact. The effect of El Niño on deforestation fires was greatest outside of reserves and near roads. Indigenous reserves, limited-use reserves, and fully protected reserves all had fewer fires than outside areas and did not appear to differ in their effectiveness. CONCLUSIONS/SIGNIFICANCE: Taking time, regional factors, and climate into account, our results show that reserves are an effective tool for curbing destructive burning in the Amazon.