Spatial and Temporal Trends of Deer Harvest and Deer-Vehicle Accidents in Ohio

Author Institution: Buckeye Valley High School ; USDA Forest Service, Delaware CountyWhite-tailed deer (Odocoileus virginianus} have been increasing dramatically in the eastern United States, with concomitant increases in impacts resulting from deer browsing and deer-vehicle collisions. In Ohio, the number of deer were estimated at near zero in 1940 to over 450,000 in 1995. We analyzed estimates of deer harvest and deer-vehicle collisions in 1995 for 88 counties in Ohio. These data were also related to county-level spatial data on the length of major highways, urban land, rural land, crop land, forest land, all land, and human population. The objectives of this study were to evaluate the spatial and temporal trends of white-tailed deer across Ohio and to relate these patterns to the formerly mentioned environmental and human variables. For 1995 data, positive relationships existed between the amount of urban land in the county versus the number of deer-vehicle collisions, the amount of forest land in the county versus the number of deer harvested, the human population of a county versus the number of deer-vehicle collisions, and the length of major highways in a county versus the number of deer-vehicle collisions. Negative relationships existed between the amount of crop land in a county versus the number of deer harvested, the amount of crop land versus the number of deer-vehicle collisions, and the amount of urban land versus the number of deer harvested. Nine counties, representing various levels of land-use and human population tendencies, were analyzed for historic trends in deer harvest (1985-1995) and deer-vehicle collisions (1988-1995); in each case, there were substantial rises over the previous decade. Extensions of the resulting regression lines show the possibility for continued increases in deervehicle collisions, especially those with a high human population and forest cover. The dramatic increases in deer populations can be attributed to increasing forest land in the state, more habitat of shrubby land, few predators, mild winters, and the deer's ability to adapt to human-inhabited environments

The Role of Pioneering Species on the Reclamation of North Dakota Surface Mined Lands

Four reclaimed mined areas in western North Dakota ranging in age from one to four years since mining, along with a site from a native mixed grass prairie for comparison, were studied to quantify the early successional changes in floristic composition, soil chemistry and plant chemical composition. The mined sites had been contoured, topsoiled, fertilized, and seeded. However, analysis of the seed bank in topsoil showed that the most dominant colonizers immigrate after topsoiling. Of the 95 species encountered, Kochia scoparia was the most dominant in the first two years following mining. Kochia had relatively low densities 2 in the first year (50-80/m ), but were robust and attained heights 2 of 88 cm with a biomass of about 400 g/m . In the second year, the 2 plant densities increases to over 10,000/m but the height and 2 biomass were reduced to 15 cm and 90 g/m . However, during the third and fourth years Kochia density declined and was practically nonexistent by the fourth year, while the planted Agropyron grasses had concomitantly increased. Other pioneers like Amaranthus retroflexus, Chenopodium album, Helianthus annuus, Salsola spp., and Setaria spp. showed a less abrupt but similar decline. Chemical analysis of the soils over the same time period showed decreases in electrical conductivity (E.C.) and in the concentrations of Ca, Mg, Na, Li, Sr, and S04 (due to leaching), while organic matter (O.M.) increased. Field studies were conducted on the interspecific relations of the dominant species during early succession - Kochia, Salsola collina and Agropyron spp. It was found that Kochia and Salsola acted as nurse crops for several months during the first year of Agropyron spp. establishment, but then began to shade heavily by late July thus reducing grass tillering. Field and growth chamber experiments on the intraspecific relations of Kochia demonstrated that it conformed to the laws of reciprocal yield, self-thinning, and constant final yield. Autotoxicity in Kochia appears to be the main factor causing the decline in its density. A field experiment indicated that thinning dense second year Kochia stands to the density of first year stands did not alter the growth of Kochia, providing strong evidence for autotoxicity. Similarly, several growth chamber experiments demonstrated that small amounts of decaying Kochia leaves and especially roots were toxic to Kochia growth, but not Melilotus officinalis or Agropyron caninum. Chemical analysis of the soils and tissues indicated nutritional imbalances as shown by P/Zn and P/Mn ratios may be responsible for the autotoxicity. In addition to Kochia, a bioassay experiment showed allelochemics to be important in several other colonizing species. Results indicated that later stage species generally have greater toxicities than first year colonizers. An analysis of the seeds present in topsoils (a grazed area, an ungrazed area, and two stockpiles) indicated that seeds of the most prevalent colonizers were not present in the topsoil upon respreading but rather appeared by immigration from the surrounding areas. The grazed site had a seed density of over 7,700 seeds/m^ (of which 43% were from weedy species) and the ungrazed site had 3,900 seeds/m (of which 1/ were weeds); the stockpiles of topsoil had very low seed densities. Mowing of first year Kochia and Salsola just prior to seed set benefited the establishment of grasses, since Agropyron spp. produced over eight times greater biomass after mowing compared with Kochia which produced only one-fourth the biomass. Burning dead Kochia stems and seedlings in second year helped other weedy species; grass growth was impaired. Burning of a six year old reclaimed site resulted in significant reductions in soil water, standing dead biomass, and litter, and some differences in biomass of the species components; however, biomass of species of Agropyron increased whereas those of Stipa decreased by burning. Overall, no significant differences in total live biomass were recorded within two years after the burn

Biological Control, Biodiversity, and Multifunctionality in Coffee Agroecosystems.

In recent decades, ecologists have come to appreciate what many farmers have long known—that biodiversity and ecological complexity play essential roles in many of the processes occurring in agroecosystems. These include many ecosystem services and functions, such as biological control, pollination, and soil fertility and preservation. At the same time, ecologically complex agroecosystems are extremely important for the maintenance of biodiversity at local and at regional scales. In short, diverse agroecosystems help to maintain biodiversity, and biodiversity helps to maintain critical functions and services in these agroecosystems. As such, it is critical to understand the role of ecological complexity in and around agroecosystems so as to maximize the benefits to the conservation of biodiversity and of ecosystem services. I focused my questions on the service of biological control and the biodiversity of natural enemies, and I performed my research on coffee farms in Mexico and Puerto Rico. First, I addressed the importance of natural enemy diversity on biological control, where I studied two ladybeetle predators of a coffee pest. I concluded that through niche partitioning, these beetles coexist and enhance overall biocontrol through species complementarity. Then, using a quantitative review, I addressed how natural enemies are influenced by ecological complexity at various scales. I found that landscape complexity may play a more important role than local heterogeneity in determining enemy abundance and diversity. Next, I focused on one natural enemy guild, parasitoid wasps, and assessed how they respond to ecological complexity at local and landscape scales. Then, through meta-analysis, I addressed the challenge of attaining farms that are both productive and that retain high levels of biocontrol. I found that win-win relationships between biocontrol and yield are probable under certain planting conditions. Finally, I take a multifunctional approach and assess how multiple taxa and multiple ecosystem services respond to ecological complexity. I found that farms can be most profitable and conserve high biodiversity if incentive structures exist to support vegetationally complex farms. In summary, my dissertation research demonstrates the importance of ecological complexity in coffee farms for biodiversity conservation and ecosystem services, such as biocontrol.PHDEcology and Evolutionary BiologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/113309/1/iverson_1.pd

Emerald Ash Borer (Agrilus planipennis): Towards a Classifcation of Tree Health and Early Detection

Author Institution: U. S. Forest Service, Northern Research StationAuthor Institution: School of Environment & Natural Resources, The Ohio State UniversityForty-five green ash (Fraxinus pennsylvanica) street trees in Toledo, Ohio were photographed, measured, and visually rated for conditions related to emerald ash borer (Agrilus planipennis)(EAB) attacks. These trees were later removed, and sections were examined from each tree to determine the length of time that growth rates had been impacted. A classification system was developed to discern the health of the trees along with a proposed method for early detection of a declining state of vigor. The classification is not an indicator of the degree of infestation, but rather tree health, which may be linked to the degree of EAB infestation. An evaluation of the tree sections places the EAB establishment no later than the 2004 growing season. A three-class system formulated from the evaluation of epicormic shoots, canopy light transmission, and EAB exit holes can be used to monitor the health of ash trees during EAB outbreaks. The classification system could potentially give homeowners, property managers, and agencies a way to detect and treat this problem earlier, especially in urban and park settings, and before trees are fully infested and exhibiting later-stage signs of decline. It is probably not practical for forest applications. Early detection and treatment not only can save selected trees, but it also might slow the spread of the insect, thereby giving additional trees a chance to survive the initial invasion

Agroforestry landscapes and global change: landscape ecology tools for management and conservation

Forest ecosystems are impacted by multiple uses under the influence of global drivers, and where landscape ecology tools may substantially facilitate the management and conservation of the agroforestry ecosystems. The use of landscape ecology tools was described in the eight papers of the present special issue, including changes in forested landscapes due to agricultural and forestry activities, landscape changes due to recent intensification of agriculture, and the impacts of agroforestry as compared to natural forest ecosystems. Landscape ecology can improve the economic, environmental and social values of agroforestry, and this knowledge should help to develop new management alternatives for agroforestry. We believe that these papers will inform management at the landscape level, especially in agroforestry landscapes, offering new tools for management and conservation.EEA Santa CruzFil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas. Laboratorio de Recursos Agroforestales; ArgentinaFil: Andrieu, Emilie. Institut National de la Recherche Agronomique; FranciaFil: Iverson, Louis R. USDA Forest Service. Northern Research Station; Estados UnidosFil: Peri, Pablo Luis. Universidad Nacional de la Patagonia Austral; Argentina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

An integrated assessment of the potential impacts of climate change on Indiana forests

Forests provide myriad ecosystem services, many of which are vital to local and regional economies. Consequently, there is a need to better understand how predicted changes in climate will impact forests dynamics and the implications of such changes for society as a whole. Here we focus on the impacts of climate change on Indiana forests, which are representative of many secondary growth broadleaved forests in the greater Midwest region in terms of their land use history and current composition. We find that predicted changes in climate for the state – warmer and wetter winters/springs and hotter and potentially drier summers – will dramatically shape forest communities, resulting in new assemblages of trees and wildlife that differ from forest communities of the past or present. Overall, suitable habitat is expected to decline for 17-29 percent of tree species and increase for 43-52 percent of tree species in the state, depending on the region and climate scenario. Such changes have important consequences for wildlife that depend on certain tree species or have ranges with strong sensitivities to climate. Additionally, these changes will have potential economic impacts on Indiana industries that depend on forest resources and products (both timber and non-timber). Finally, we offer some practical suggestions on how management may minimize the extent of climate-induced ecological impacts, and highlight a case study from a tree planting initiative currently underway in the Patoka River National Wildlife Refuge and Management Area

Does the marine biosphere mix the ocean?

Author Posting. © Sears Foundation for Marine Research, 2006. This article is posted here by permission of Sears Foundation for Marine Research for personal use, not for redistribution. The definitive version was published in Journal of Marine Research 64 (2006): 541-561, doi:10.1357/002224006778715720.Ocean mixing is thought to control the climatically important oceanic overturning circulation. Here we argue the marine biosphere, by a mechanism like the bioturbation occurring in marine sediments, mixes the oceans as effectively as the winds and tides. This statement is derived ultimately from an estimated 62.7 TeraWatts of chemical power provided to the marine environment in net primary production. Various approaches argue something like 1% (.63 TeraWatts) of this power is invested in aphotic ocean mechanical energy, a rate comparable to wind and tidal inputs

Interpreting forest biome productivity and cover utilizing nested scales of image resolution and biogeographical analysis

The objective was to relate spectral imagery of varying resolution with ground-based data on forest productivity and cover, and to create models to predict regional estimates of forest productivity and cover with a quantifiable degree of accuracy. A three stage approach was outlined. In the first stage, a model was developed relating forest cover or productivity to TM surface reflectance values (TM/FOREST models). The TM/FOREST models were more accurate when biogeographic information regarding the landscape was either used to stratigy the landscape into more homogeneous units or incorporated directly into the TM/FOREST model. In the second stage, AVHRR/FOREST models that predicted forest cover and productivity on the basis of AVHRR band values were developed. The AVHRR/FOREST models had statistical properties similar to or better than those of the TM/FOREST models. In the third stage, the regional predictions were compared with the independent U.S. Forest Service (USFS) data. To do this regional forest cover and forest productivity maps were created using AVHRR scenes and the AVHRR/FOREST models. From the maps the county values of forest productivity and cover were calculated. It is apparent that the landscape has a strong influence on the success of the approach. An approach of using nested scales of imagery in conjunction with ground-based data can be successful in generating regional estimates of variables that are functionally related to some variable a sensor can detect

Mid-Atlantic forest ecosystem vulnerability assessment and synthesis: a report from the Mid-Atlantic Climate Change Response Framework project

Forest ecosystems will be affected directly and indirectly by a changing climate over the 21st century. This assessment evaluates the vulnerability of 11 forest ecosystems in the Mid-Atlantic region (Pennsylvania, New Jersey, Delaware, eastern Maryland, and southern New York) under a range of future climates. We synthesized and summarized information on the contemporary landscape, provided information on past climate trends, and described a range of projected future climates. This information was used to parameterize and run multiple forest impact models, which provided a range of potential tree responses to climate. Finally, we brought these results before two multidisciplinary panels of scientists and land managers familiar with the forests of this region to assess ecosystem vulnerability through a formal consensus-based expert elicitation process