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Review Of Bird Repellents, Larry Clark Jan 1998

Review Of Bird Repellents, Larry Clark

Vertebrate Pest Conference Proceedings: 18th (1998)

Despite a general perception that there is an abundance of nonlethal control technologies, the fact remains that there are fewer registered products and active ingredients for repellents in the U.S. than there were 10 and 20 years ago. This review discusses the technical issues relating to the discovery, formulation, and delivery of chemical repellents, and suggests future avenues of research that would improve our ability to develop effective chemical repellents.


1998 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie Jan 1998

1998 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie

Data Sets

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the photo point locations, aerial photos, and flight maps for the year 1998.


1998 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group Jan 1998

1998 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group

Images

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the aerial photos for the year 1998.


Earlj Life Historj And Recruitment Of Black Crappie (Pomoxis Nigromaculatus) In Two South Dakota Waters, K. L. Pope, D. W. Willis Jan 1998

Earlj Life Historj And Recruitment Of Black Crappie (Pomoxis Nigromaculatus) In Two South Dakota Waters, K. L. Pope, D. W. Willis

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We compared the early life history of black crappie (Pomoxis nigromaculatus) in Richmond (an impoundment) and Brant (a natural lake) lakes during 1994-1996. We expected variable recruitment (i.e., missing year classes) in the natural lake and more consistent recruitment in the impoundment. Larval black crappie abundance was always higher in Richmond Lake than Brant Lake. Peak abundance of larval black crappie was highest during 1994 in both waters. However, peak larval abundance did not correspond with fall trap-net catch per unit effort (CPUE) of age-0 black crappie, which was highest during 1995. Thus, recruitment of black crappie was …


Population Growth Of Antarctic Fur Seals: Limitation By A Top Predator, The Leopard Seal?, Peter L. Boveng, Lisa M. Hiruki, Michael K. Schwartz, John L. Bengtson Jan 1998

Population Growth Of Antarctic Fur Seals: Limitation By A Top Predator, The Leopard Seal?, Peter L. Boveng, Lisa M. Hiruki, Michael K. Schwartz, John L. Bengtson

United States Department of Commerce: Staff Publications

Antarctic fur seals (Arctocephalus gazella) in the South Shetland Islands are recovering from 19th-century exploitation more slowly than the main population at South Georgia. To document demographic changes associated with the recovery in the South Shetlands, we monitored fur seal abundance and reproduction in the vicinity of Elephant Island during austral summers from 1986/1987 through 1994/1995. Total births, mean and variance of birth dates, and average daily mortality rates were estimated from daily live pup counts at North Cove (NC) and North Annex (NA) colonies on Seal Island. Sightings of leopard seals (Hydrurga leptonyx) and incidents …


Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller Jan 1998

Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study shows that chemical properties of two restiad species, Empodisma minus and Sporadanthus traversii, may contribute to their success as peat-formers in a climate of the North Island of New Zealand which is not conducive to raised mire development. Unlike Sphagnum, the equivalent northern hemisphere peat-former, restiads possess lignin in their tissues. In addition, the presence of non-lignin polyphenols (including tannins and phenolic acids) in restiads may be an important factor in peat formation due to the allelopathic decay retardation. Patterns of degradation of plant biopolymers have been examined and the pathway of degradation of monocotyledons (loss …


The Determination Of The Potential Of Australian Native Plants To Phytoremediate Lead, Desmond Dev Menon Jan 1998

The Determination Of The Potential Of Australian Native Plants To Phytoremediate Lead, Desmond Dev Menon

Theses : Honours

Industrial activities and natural occurrences of mineral ores can both result in the presence of high concentrations of heavy metals in the soil. These toxic metals have been shown to adversely affect human health and the environment. Currently, three main technologies are being used to solve this problem of soil contamination. These are incineration, landfill construction and physico-chemical treatments. The economic and environmental costs of each of these technologies tend to outweigh the merits of their application, especially where contaminated areas are small. These techniques do not necessarily remove the heavy metals from the soil, and can also inhibit biological …


The Probe, Issue 184 – January 1998 Jan 1998

The Probe, Issue 184 – January 1998

The Probe: Newsletter of the National Animal Damage Control Association

NADCA Election Results!
PRESIDENT Robert H. Giles, Jr. (VA) VICE PRESIDENT - WEST Mark Collinge (ID) VICE PRESIDENT - EAST Pete Butchko (MS) SECRETARY Richard B. Chipman (VT) TREASURER Grant Huggins (OK)
REGIONAL DIRECTORS: Western (1): Diane deLorimier (CA) Southern Rockies (2): GaryWitmer (CO) Northern Rockies (3): George E. Graves (ID) South Central (4): James R. Gallaspy (LA) North Central (5): James C. Luchsinger (NE) Great Lakes (6): Mike Dwyer (OH) Northeastern (7): Jerry L. Pickel (PA) Centraleastern (8): JohnM. Houben (VA) Southeastern (9): D. Tommy King (MS)
From Our Incoming President: An Opinion....-- Robert H. Giles, Jr.
Carrie Hunt …


Center For Sustainable Agricultural Systems Newsletter, January/February 1998 Jan 1998

Center For Sustainable Agricultural Systems Newsletter, January/February 1998

Center for Sustainable Agricultural Systems: Newsletter (1993–2000)

Contents:

National Organic Program Proposed Rule

National Strategy to Assist Small Farms

North Central Region SARE Offers Producer Grants

Educators Invited to Attend SARE Celebration

Integrated Farm Update: Small Grain Cover Crops in Crop/Livestock Systems

Future Food Systems: Implications for Nebraska

Symposium: Preserving Farmland, Policies and Practices


Owls Of The Idaho National Engineering And Environmental Laboratory (Ineel), Natalie A. Fahler Jan 1998

Owls Of The Idaho National Engineering And Environmental Laboratory (Ineel), Natalie A. Fahler

Electronic Theses and Dissertations

The Idaho National Engineering and Environmental Laboratory (INEEL) is a 2,315 km2 energy research and development site located on the Upper Snake River Plain of Southeast Idaho. Owl research was conducted on the site during the spring and summers of 1996-1997. Objectives were to: a) determine productivity, habitat use, and possible nest site selection factors of burrowing owls (Athene cunicularia ), b) verify the presence of small owl species including the boreal owl (Aegolius funereus), the northern saw-whet owl (A. acadicus), the western screech owl (Otus kennicottii), the flammulated owl (0. flammeolus), and the northern pygmy owl (Glaucidium gnoma), c) …


The Wind Cave National Park Elk Herd: Home Ranges, Seasonal Movements, And Alternative Control Methods, Peter Bauman Jan 1998

The Wind Cave National Park Elk Herd: Home Ranges, Seasonal Movements, And Alternative Control Methods, Peter Bauman

Electronic Theses and Dissertations

Elk (Cervus elaphus ne/soni) herd organization, movements, and home range size in Wind Cave National Park (WICA) were studied from May 1996 to August 1997. Twenty radiocollared elk ( 10 males, 10 females) were relocated by ground and aerial telemetry. Radiocollared elk were relocated two times/week, resulting in 1,595 relocations ( 410 ground, 1, 185 aerial). Coefficients of association (CA) for radiocollared cows averaged 0.005 during spring/summer 1996, 0.033 during spring/summer 1997, and 0.295 during falVwinter 1996. Coefficients of association for radiocollared bulls averaged 0.011 during spring/summer 1996, 0.015 during spring/summer 1997, and 0.075 during faIVwinter 1996. Three cow subherds …


Adding Nutrients To Enhance The Growth Of Endangered Sockeye Salmon: Trophic Transfer In An Oligotrophic Lake, Phaedra E. Budy, Chris Luecke, Wayne A. Wurtsbaugh Jan 1998

Adding Nutrients To Enhance The Growth Of Endangered Sockeye Salmon: Trophic Transfer In An Oligotrophic Lake, Phaedra E. Budy, Chris Luecke, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Snake River sockeye salmon Oncorhynchus nerka, listed under U.S. law as endangered in 1991 in response to a decline in anadromous adult numbers, spend their first 1–2 years in Redfish Lake, Idaho, before migrating to the sea. To determine how nutrient enhancement might influence phytoplankton, zooplankton, and fish production, we performed fertilization experiments in large enclosures in this oligotrophic lake using juvenile kokanee (lacustrine O. nerka) as analogues for endangered sockeye salmon. Fertilization of the metalimnion substantially increased chlorophyll a (150%), phytoplankton biovolume (75%), primary productivity (250%), and zooplankton biomass (200%), and moderately increased fish growth (12%) over our control …


Mesozooplankton Distribution And Abundance In The Pagan River: A Nutrient Enriched Subestuary Of The James River, Virginia, Lillian N. Davis, Harold G. Marshall Jan 1998

Mesozooplankton Distribution And Abundance In The Pagan River: A Nutrient Enriched Subestuary Of The James River, Virginia, Lillian N. Davis, Harold G. Marshall

Biological Sciences Faculty Publications

The mesozooplankton in the Pagan River was dominated by calanoid copepods, with abundance peaks occurring during late winter-early spring and from late summer into early fall. This included spring, summer, and fall abundance maxima. The total mean abundance of the mesozooplankton was 3,008/m3.


Phosphorus In The Landscape: Diffuse Sources To Surface Waters. Land And Water Resources Research And Development Corporation. Occasional Paper 16/98, Richard Davis, Anne Hamblin, E O'Loughlin, Nic Austin, R Banens, P Cornish, P Hairsin, M Mcculloch, Phil Moody, J Olley, B Prove, I Smalls, David Weaver Jan 1998

Phosphorus In The Landscape: Diffuse Sources To Surface Waters. Land And Water Resources Research And Development Corporation. Occasional Paper 16/98, Richard Davis, Anne Hamblin, E O'Loughlin, Nic Austin, R Banens, P Cornish, P Hairsin, M Mcculloch, Phil Moody, J Olley, B Prove, I Smalls, David Weaver

All other publications

The National Eutrophication Management Program (NEMP) and Environment Australia convened a workshop to develop a coherent overview of the sources and transport of diffuse phosphorus in Australian catchments based on the latest knowledge. The Land and Water Resources Research and Development Corporation (LWRRDC) and the Murray–Darling Basin Commission (MDBC) jointly fund NEMP. A select group of scientists attended the workshop and developed a coherent statement about phosphorus sources and transport in Australian catchments. The group did not extend this statement to include recommended management practices. This paper reports the findings from the workshop. State governments have developed algal and nutrient …


Ecological Resilience, Biodiversity, And Scale, Garry D. Peterson, Craig R. Allen, C. S. Holling Jan 1998

Ecological Resilience, Biodiversity, And Scale, Garry D. Peterson, Craig R. Allen, C. S. Holling

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We describe existing models of the relationship between species diversity and ecological function, and propose a conceptual model that relates species richness, ecological resilience, and scale.We suggest that species interact with scale-dependent sets of ecological structures and processes that determine functional opportunities. We propose that ecological resilience is generated by diverse, but overlapping, function within a scale and by apparently redundant species that operate at different scales, thereby reinforcing function across scales. The distribution of functional diversity within and across scales enables regeneration and renewal to occur following ecological disruption over a wide range of scales.


Larval Black Crappie Distribution: Implications For Sampling Impoundments And Natural Lakes, Kevin L. Pope, David W. Willis Jan 1998

Larval Black Crappie Distribution: Implications For Sampling Impoundments And Natural Lakes, Kevin L. Pope, David W. Willis

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

An understanding of larval fish distributions is essential for developing an appropriate sampling design to monitor larval abundances. We monitored abundance of larval black crappie Pomoxis nigromaculatus to assess spatial differences in Richmond Lake (a 336-ha impoundment) and Brant Lake (a 405-ha natural lake), South Dakota, during 1994–1996. Age-0 black crappies were collected with a 500-µm mesh ichthyoplankton trawl from fixed sites within each water body. In the impoundment, larval black crappies were collected over a longer period at the upper site than at the dam site during 1994 and 1995. In the natural lake, larval black crappie abundances were …


1997 Inventory For Spiranthes Diluvialis Sheviak In Western Nebraska: A Final Report, Volume Ii, Terri Hildebrand Jan 1998

1997 Inventory For Spiranthes Diluvialis Sheviak In Western Nebraska: A Final Report, Volume Ii, Terri Hildebrand

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This study resulted from an agreement between Nebraska Game and Parks Commission (NGPC) and the United States Fish and Wildlife Service (USFW). After the 1996 discovery of Spiranthes diluvialis, in western Nebraska, NGPC was seeking to determine the extent of the Nebraska population. Information on the wet meadow community of orchid occurrence in Nebraska and eastern Wyoming was needed. This report includes descriptions of communities inventoried, Spiranthes diluvialis populations, and additional species monitored by Nebraska and Wyoming Natural Heritage programs.

Between May and September 1997, potential Spiranthes diluvialis habitat was inventoried for occurrences of the orchid. For all sites …


Declines In Benthic Macroinvertebrate Populations In Southern Lake Michigan, 1980–1993, Thomas F. Nalepa, David J. Hartson, David L. Fanslow, Gregory A. Lang, Stephen J. Lozano Jan 1998

Declines In Benthic Macroinvertebrate Populations In Southern Lake Michigan, 1980–1993, Thomas F. Nalepa, David J. Hartson, David L. Fanslow, Gregory A. Lang, Stephen J. Lozano

United States Department of Commerce: Staff Publications

Densities of the major benthic macroinvertebrate groups declined dramatically at sites shallower than 50 m in southern Lake Michigan between 1980 and 1993. Declines in Diporeia, Oligochaeta, and Sphaeriidae ranged from 40 to 75% at these depths. Total densities declined from 16 800·m–2 in 1980–1981 to 4,800·m–2 in 1992–1993 at sites in the 16–30 m depth interval and from 21,300 to 11,300·m–2 at sites in the 31–50 m depth interval. Changes at sites deeper than 50 m were minimal; only sphaeriids declined to any extent. Declines in oligochaetes and sphaeriids occurred uniformly throughout the nearshore region …


1998 Platte River Basin Ecosystem Symposium Proceedings Jan 1998

1998 Platte River Basin Ecosystem Symposium Proceedings

Water Current Newsletter

No abstract provided.


Status Of Aphis Vertebrate Pesticides And Drugs, Kathleen A. Fagerstone, Edward W. Schafer Jr. Jan 1998

Status Of Aphis Vertebrate Pesticides And Drugs, Kathleen A. Fagerstone, Edward W. Schafer Jr.

Vertebrate Pest Conference Proceedings: 18th (1998)

The Wildlife Services (WS) Program manages wildlife/human conflicts by using an integrated approach employing some vertebrate pesticides. These are used in such small quantities that private industry cannot afford to register and produce them profitably. On behalf of WS, the Animal and Plant Health Inspection Service (APHIS) maintains about 30 federal and state pesticide registrations, containing seven active ingredients, with the U.S. Environmental Protection Agency (EPA). These include: the Compound 1080 Livestock Protection Collar, DRC-1339 Concentrates (Starlicide), Gas Cartridges (carbon and sodium nitrate), the M-44 (sodium cyanide), and a number of baits and concentrates containing Strychnine Alkaloid and Zinc Phosphide. …


Tsw Wildlife Damage Management Working Group Newsletter:Spring 1998 - Volume 5(2) - Election Issue Jan 1998

Tsw Wildlife Damage Management Working Group Newsletter:Spring 1998 - Volume 5(2) - Election Issue

TWS Wildlife Damage Management Working Group Newsletter

Forward -- Scott Hygnstrom Postdoctoral Position With The Jack Berryman Institute; 1998 Winners Of The Jack H. Berryman Institute Awards; Preliminary Program For The Wildlife Society 5th Annual Conference, September 22-26, 1998, Buffalo, Ny; Candidates For The Working Group Executive Board Future Newsletter; Contributions; From Around The World!; Wildlife Damage Management Working Group Ballot - May 1998 ; Plenary Abstracts From The 18th Vertebrate Pest Conference, 2-5 March 1998, Costa Mesa, Ca; Available Publications; Future Events Of Interest; Next Edition Deadline; Application For Membership / The Wildlife Society; Contributors To This Issue


Tws Wildlife Damage Management Working Group Newsletter: Fall 1998 - Volume 5(4) Jan 1998

Tws Wildlife Damage Management Working Group Newsletter: Fall 1998 - Volume 5(4)

TWS Wildlife Damage Management Working Group Newsletter

Forward -- Scott Craven; The Wildlife Society Wildlife Damage Management Working Group 1998 Annual Meeting September 23, 1998, 6-8 Pm, Buffalo, Ny; Next Edition Deadlines; The Wildlife Society Wildlife Damage Management Working Group 1998 Report To Council; Candidates For The Working Group Officers - December 1998 ; 1998-99 Wildlife Damage Management Working Group Officers; Wildlife Damage Management Working Group Ballot - December 1998; Wildlife Damage Management Around The World - Part 2; Sika Deer Management In Nikko National Park, Japan; Current Status And Future Direction; Contributors To This Issue ; Application For Membership / The Wildlife Society


Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty Jan 1998

Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty

Peer Reviewed Publications

Concern exists over the effects of interacting environmental stresses on the ecological integrity of temperate forests. Coincidence of sensitivity to drought, increasing occurrence of defoliation, and elevated pollutant deposition has produced speculation that northern hardwood forests may be susceptible to the increased climatic stresses projected for the Great Lakes region. The objective of our study was to examine relationships among environmental stress factors, vigor, mortality, and growth in northern hardwood forests located along a pollution-climate gradient in the Great Lakes region. Between 1987 and 1993, we quantified climatic variables, pollutant deposition, insect defoliation, and tree vigor and growth at five …


Phytoplankton Composition Within The Tidal Freshwater Region Of The James River, Virginia, Harold G. Marshall, Lubomira Burchardt Jan 1998

Phytoplankton Composition Within The Tidal Freshwater Region Of The James River, Virginia, Harold G. Marshall, Lubomira Burchardt

Biological Sciences Faculty Publications

Based on a 10.5 year data set, 271 taxa were identified at a single tidal freshwater station in the James River. The mean monthly concentrations of major algal categories, total biomass and productivity are given. Diatom maxima were associated with peak periods of river discharge, with chlorophytes, cyanobacteria, and autotrophic picoplankton abundance and productivity greater during reduced river flow and more stable water conditions.


Evaluation Of Toxicity, Bioavailability And Speciation Of Lead, Zinc And Cadmium In Mine/Mill Wastewaters, Mujde Erten-Unal, Bobby G. Wixson, Nord Gale, Jerry L. Pitt Jan 1998

Evaluation Of Toxicity, Bioavailability And Speciation Of Lead, Zinc And Cadmium In Mine/Mill Wastewaters, Mujde Erten-Unal, Bobby G. Wixson, Nord Gale, Jerry L. Pitt

Civil & Environmental Engineering Faculty Publications

The toxicity of common compounds of lead, cadmium and zinc was evaluated in waters similar to that found in the world's largest lead producing area in Missouri. Static, acute toxicity tests were performed using fathead minnows (Pimephales promelas) and water fleas (Daphnia magna) respectively. Test organisms were subjected to varying amounts of sulfide, carbonate, chloride and sulfate salts of lead, zinc and cadmium mixed in hard, alkaline waters typical to this region. Median lethal concentrations were calculated using nominal versus measured metal concentrations. Measured metal concentrations included four different metal fractionation (extraction/filtration) techniques at different pH …


Northern Australia Quarantine Strategy. Weeds Target List, B. M. Waterhouse, A A. Mitchell Jan 1998

Northern Australia Quarantine Strategy. Weeds Target List, B. M. Waterhouse, A A. Mitchell

Biosecurity published reports

Second edition.

The Northern Australia Quarantine Strategy (NAQS) was established in 1989 as an outcome of a major evaluation of quarantine in Australia (AGPS 1987, 1988). NAQS activities include surveying for weeds,insect pests and diseases of plants; and pests and diseases of animals in northern Australia, Papua New Guinea and Indonesia. The primary goal is to provide early detection and warning of new quarantine threats or incursions.

A targetted approach was adopted for all pests, diseases and weeds. For each category of pest, experts in the discipline compiled lists of organisms not known from Australia but known to occur in …


Reefs As Contributors To The Diversity Of Epiphytic Algal Communities In Seagrass Meadows, B. R. Van Elvan Jan 1998

Reefs As Contributors To The Diversity Of Epiphytic Algal Communities In Seagrass Meadows, B. R. Van Elvan

Theses : Honours

It has recently become dogma that reef systems arc a source of diversity to algal epiphyte communities in adjacent seagrass meadows. While this theory had not been tested, it was often cited as the reason for unexpected results in algal studies and marine pollution monitoring. This study examined whether reefs do in fact contribute to the diversity of seagrass epiphytes by testing the effect of distance from reef on seagrass epiphyte communities. The study was conducted in the vicinity of Carnac and Garden Islands and Parmelia Bank, off the coast of Fremantle, Western Australia. Three habitat types were selected as …


Land Transformation, Highly Governed Landscapes And Landscape Health: A Case Study Of The Lower Piave Area Of Northeastern Italy, Pietro Bertollo Jan 1998

Land Transformation, Highly Governed Landscapes And Landscape Health: A Case Study Of The Lower Piave Area Of Northeastern Italy, Pietro Bertollo

Theses and Dissertations (Comprehensive)

This dissertation examines the issue of biophysical landscape health. Its primary objective is to produce an interpretation of biophysical landscape health for the highly governed landscapes of the Lower Piave area of northeastern Italy. Highly governed landscapes are considered to be those which are highly controlled by humans to an even greater degree than normal cultural landscapes. An example is reclaimed agricultural landscapes such as those of the northeastern Italian coastal belt, from which the Lower Piave case study is drawn. These landscapes are highly governed because without constant human intervention, they would revert back to their former marsh state. …


An Approach To Defining Greater Park Ecosystems And Its Application To Gros Morne National Park (Newfoundland), Karl Keough Jan 1998

An Approach To Defining Greater Park Ecosystems And Its Application To Gros Morne National Park (Newfoundland), Karl Keough

Theses and Dissertations (Comprehensive)

Ecosystem management is an integrative, cooperative, adaptive approach to resource management that has evolved in response to the growing number of environmental and resource problems over the past several decades. One such problem, the threat to the world’s biodiversity, may be attributed to the destruction, degradation, and fragmentation of habitat resulting from the expanding human population, and the inability to set aside in strict nature reserves, sufficient habitat for wide-ranging mammals and fully functioning ecosystems. The Greater Park Ecosystem concept may be seen as the embodiment of ecosystem management in national parks and a response to the threat to biodiversity. …


Seasonal Patterns Of Nitrogen Fixation In Termites, A. D. Curtis, D. A. Waller Jan 1998

Seasonal Patterns Of Nitrogen Fixation In Termites, A. D. Curtis, D. A. Waller

Biological Sciences Faculty Publications

Summary

1. Termite nitrogenase activity was highest in autumn and spring (≈ 3 µg N2 fixed termite fresh mass (g)–1 day–1) and lowest in winter and summer (≈ 0·8 µg N2 fixed termite fresh mass (g)–1 day–1).

2. The nitrogenase activity of worker termites was significantly higher than all other castes (1·58 ± 0·27 µg N2 fixed termite fresh mass (g)–1 day–1).

3. Worker termites constituted the largest proportion of all the castes throughout the study period (≈ 90%).

4. The localized input of fixed nitrogen by termites …