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Articles 31 - 60 of 64

Full-Text Articles in Terrestrial and Aquatic Ecology

Effects Of Harvest Regulations And Post-Release Hooking Mortality On Walleye Populations In South Dakota, Cade Lyon Jan 2021

Effects Of Harvest Regulations And Post-Release Hooking Mortality On Walleye Populations In South Dakota, Cade Lyon

Electronic Theses and Dissertations

Harvest regulations are commonly implemented to manipulate fisheries stocks. By regulating the size and number of fish that are harvested by anglers, managers are able to meet the goals and needs of regions. However, these management actions come with the potential for negative consequences. Overexploitation due to less restrictive harvest regulations can cause collapses in fisheries populations. In addition, indirect consequences such as hooking mortality brought on by length-based regulations can also be detrimental to populations. In this study, I investigated the effects of various harvest regulations on Walleye populations in three western South Dakota irrigation reservoirs: Angostura, Belle Fourche, …


Integration Of Crop-Livestock Systems: An Opportunity Toprotect Grasslands From Conversion To Cropland In The Us Great Plains, Alexander J. Smart, Daren Redfearn, Robert Mitchell, Tong Wang, Cody Zilverberg, Pete J. Bauman, Justin D. Derner, Julie Walker, Cody Wright Jan 2020

Integration Of Crop-Livestock Systems: An Opportunity Toprotect Grasslands From Conversion To Cropland In The Us Great Plains, Alexander J. Smart, Daren Redfearn, Robert Mitchell, Tong Wang, Cody Zilverberg, Pete J. Bauman, Justin D. Derner, Julie Walker, Cody Wright

Native Plant Focused Publications

The Great Plains is a mixture of cropland and grassland mainly used for agricultural purposes, with grasslands under continual threat of conversion to cropland. Agriculturists are advocating for the integration of crop-livestock systems (ICLS) to recouple nutrient cycles, improve biodiversity, and increase resilience of agricultural operations. We address the benefits of ICLS in the Great Plains, contending that focus on improving soil health and financial stability of agricultural operations should reduce the conversion of grasslands to cropland. Using US Department of Agriculture National Agricultural Statistics Service Census of Agriculture survey data from the 1925 to 2017 category “cropland used only …


Distribution, Density, Movement, And Support For Management Of Mountain Sucker, Pantosteus Jordani, In The Black Hills Of South Dakota, Seth J. Fopma Jan 2020

Distribution, Density, Movement, And Support For Management Of Mountain Sucker, Pantosteus Jordani, In The Black Hills Of South Dakota, Seth J. Fopma

Electronic Theses and Dissertations

Mountain Sucker, Pantosteus jordani, is a cold-water species native to the Intermountain West. Fringe populations of Mountain Sucker have experienced declines in recent decades. The population of Mountain Sucker found in the Black Hills of South Dakota represents the eastern fringe of the species’ native range. Recognized as both an indicator of biologic health and as a species of greatest conservation need in South Dakota, recent studies have suggested significant declines in both distribution and abundance. Despite the recent study of Mountain Sucker in the region, increased understanding of Mountain Sucker ecology is needed to effectively manage for the conservation …


Influence Of Mink Predation On Brown Trout Survival And Size-Structure In Rapid Creek, South Dakota, Austin Galinat Jan 2020

Influence Of Mink Predation On Brown Trout Survival And Size-Structure In Rapid Creek, South Dakota, Austin Galinat

Electronic Theses and Dissertations

I compared movement, home range, habitat selection, and mortality among radio-tagged Brown Trout (Salmo trutta) at an American Mink (Neovison vison)-removal site, improved habitat site, and an undisturbed stream site in Rapid Creek, South Dakota. I observed high, post-surgery (> 26 days) survival rate (90%) of radio tagged Brown Trout. Average gross movement of Brown Trout was greater at the improved habitat site (127 m) compared to the mink removal (31 m) site, while average home range size (i.e., stream distance) among all three sites was not significantly different indicating strong site fidelity (125 to 200 m). Brown Trout movements …


Higher Temperatures Have Contrasting Effects On Different Components Of Forage Quality For Caribou In Northern Alaska, Heidi Becker Jan 2020

Higher Temperatures Have Contrasting Effects On Different Components Of Forage Quality For Caribou In Northern Alaska, Heidi Becker

Electronic Theses and Dissertations

Rising temperatures in the Arctic may affect vegetation, which in turn can affect herbivores, such as caribou, that rely on these plants for forage. Several plant traits contribute to forage quality, including digestibility, nitrogen content, and antiherbivory secondary compounds, but the effect of temperature on these traits individually and combined is unclear. I conducted a three-component study on the effect of higher temperatures on the forage quality of graminoids, deciduous shrubs, and evergreen dwarf shrubs on the North Slope of Alaska. The components included: 1) short and long-term experimental warming, 2) natural temperature variation between south and north-facing slopes, and …


Evaluation Of Fall-Seeded Cover Crops For Grassland Nesting Waterfowl In Eastern South Dakota, Charles W. Gallman Iii Jan 2020

Evaluation Of Fall-Seeded Cover Crops For Grassland Nesting Waterfowl In Eastern South Dakota, Charles W. Gallman Iii

Electronic Theses and Dissertations

The Prairie Pothole Region is the primary breeding ground for many species of North American waterfowl. This landscape was historically dominated by mixed and tallgrass prairies interspersed with wetlands, but >70% of native grassland area has been lost due to widespread conversion to croplands, which may threaten waterfowl production. Cover cropping is a re-emerging farming technique that may provide suitable nesting cover for grassland nesting waterfowl on active farmlands. My research objectives were to evaluate the utility of fall-seeded cover crops to breeding waterfowl compared to perennial cover, determine if cover crops in rotation with row crops can successfully support …


Winter Patch Grazing, Patch Burn Grazing, And Bird Communities In Western South Dakota, Jennifer Lutze Jan 2020

Winter Patch Grazing, Patch Burn Grazing, And Bird Communities In Western South Dakota, Jennifer Lutze

Electronic Theses and Dissertations

Ground nesting bird species are on a considerable decline and research efforts are being made to increase these populations throughout the Great Plains. Ground nesting bird communities found in the Northern Great Plains are driven greatly by varying amounts of cover and area size. Past research implemented patch-burn grazing to increase structural heterogeneity and to increase grassland bird habitat in the tallgrass prairie. While bird populations were very responsive to this management in the Northern Great Plains fire management is viewed negatively, especially for Midwest cattle ranchers. We implemented research to determine if winter-patch grazing on mixed grass prairie could …


Climate Change Within A Biome, Tyone Kruse, Lisa Forcier, Madhav P. Nepal, Larry B. Browning, Matthew L. Miller, P. Troy White Jan 2019

Climate Change Within A Biome, Tyone Kruse, Lisa Forcier, Madhav P. Nepal, Larry B. Browning, Matthew L. Miller, P. Troy White

iLEARN Teaching Resources

In this iLEARN lesson, students will investigate impacts of climate change on the native plants and animals, as well as the fisheries, agriculture, and forestry, within a biome of their choosing, and then develop and refine a solution for one of the impacts resulting from the climate change.


Landscapes, Water Quality And Aquatic Assemblages, Nels H. Troelstrup Jr. Jan 2019

Landscapes, Water Quality And Aquatic Assemblages, Nels H. Troelstrup Jr.

Oak Lake Field Station 30th Anniversary Retreat Presentations

No abstract provided.


Oak Lake Wetland Restoration: Difference In Hydrology Between Newly Restored And Reference Wetlands, Jennifer A. Dailey, Nels H. Troelstrup Jr. Jan 2019

Oak Lake Wetland Restoration: Difference In Hydrology Between Newly Restored And Reference Wetlands, Jennifer A. Dailey, Nels H. Troelstrup Jr.

Oak Lake Field Station 30th Anniversary Retreat Presentations

No abstract provided.


Effect Of Water Velocity And Temperature On Energy Use, Behavior, And Mortality Of Pallid Sturgeon Scaphirhynchus Albus Larvae, Joseph Thomas Mrnak Jan 2019

Effect Of Water Velocity And Temperature On Energy Use, Behavior, And Mortality Of Pallid Sturgeon Scaphirhynchus Albus Larvae, Joseph Thomas Mrnak

Electronic Theses and Dissertations

Pallid Sturgeon Scaphirhynchus albus are a federally endangered species endemic to the Missouri River basin. Natural reproduction has been limited for decades and a recruitment bottleneck is hypothesized to occur during the larval stage of development. Understanding factors that affect survival of Pallid Sturgeon larvae is key given their critical status and ongoing recovery efforts. In this study, I evaluated the effects of water velocity and temperature on energy use, behavior, and mortality of endogenously feeding Pallid Sturgeon larvae (< 25 mm TL). In the first experiment, I examined the effect of water velocity (0 – 8.3 cm s−1) on larval growth, energy density, swimming activity, and mortality. Larval growth rate at 16.3 °C was similar across …


Prairie Dogs And Livestock In Rangeland Systems: Balancing Biodiversity And Production In The Northern Mixed-Grass Prairie, Jameson Robert Brennan Jan 2019

Prairie Dogs And Livestock In Rangeland Systems: Balancing Biodiversity And Production In The Northern Mixed-Grass Prairie, Jameson Robert Brennan

Electronic Theses and Dissertations

A major constraint of beef production within the Standing Rock Reservation has been identified as a reduction in rangeland quality due in large part to wide-scale colonization by black-tailed prairie dogs (Cynomys ludovicianus). The desire exists within the community to design a holistic framework which incorporates livestock management with the goal of increasing production and rangeland health while still maintaining increased diversity associated with prairie dogs. Prairie dogs reduce the carrying capacity of cattle on rangelands by up to 50% on occupied hectares through direct consumption of vegetation and waste due to clipping to improve detection of predators. Livestock stocking …


Evaluating Bighorn Sheep Herd Response After Selective Removal Of Mycoplasma Ovipneumoniae Chronic Shedders, Tyler J. Garwood Jan 2018

Evaluating Bighorn Sheep Herd Response After Selective Removal Of Mycoplasma Ovipneumoniae Chronic Shedders, Tyler J. Garwood

Electronic Theses and Dissertations

Infected individuals vary in their contribution to disease persistence, and chronically infected individuals may sustain disease in a population. One disease that might persist in a population through chronically infected individuals is pneumonia in wild sheep. Mycoplasma ovipneumoniae (Mo), a pathogen of Caprinae commonly present in domestic sheep and goats, strongly correlates with pneumonia epizootics when it infects wild sheep populations. These epizootics can cause 40-100% herd mortality in an initial all-age dieoff, precipitate annual lamb mortality as high as 100% in following years, and sustain adult mortality long after initial all-age dieoffs. We conducted an experiment in the Black …


Vulnerability Of Protected Areas To Human Encroachment, Climate Change And Fire In The Fragmented Tropical Forests Of West Africa, Francis Kwabena Dwomoh Jan 2018

Vulnerability Of Protected Areas To Human Encroachment, Climate Change And Fire In The Fragmented Tropical Forests Of West Africa, Francis Kwabena Dwomoh

Electronic Theses and Dissertations

The Upper Guinean region of West Africa is home to some of the most globally significant tropical biodiversity hotspots, providing ecosystem services that are crucial for the region’s socio-economic and environmental wellbeing. Nonetheless, following decades of human-caused destruction of natural habitats, protected areas currently remain the only significant refugia of original vegetation relics in landscapes that are highly fragmented. Aside from having strong geographic variation in land use, climate, vegetation, and human population, the region has also experienced remarkable biophysical and socio-economic changes in recent decades. All these factors influence the fire regime and the vulnerability of forests within protected …


Weed Establishment And Persistence After Water Pipeline Installation And Reclamation In The Mixed Grass Prairie Of Western North Dakota, Erin K. Espeland, Lora B. Perkins Dec 2017

Weed Establishment And Persistence After Water Pipeline Installation And Reclamation In The Mixed Grass Prairie Of Western North Dakota, Erin K. Espeland, Lora B. Perkins

Natural Resource Management Faculty Publications

Weeds in reclamations interfere with success by: 1) competing with desirable species seeded during revegetation; 2) preventing recolonization of reclamations by native species; and 3) reducing the integrity of landscapes by expanding from reclamations into adjacent, intact areas. In the Bakken oilfield of western North Dakota, dispersed reclamation activity and increased traffic may provide many opportunities for weeds to spread. To determine the potential for disturbance and reclamation to increase resident weed populations and introduce new weed species, we tracked twenty-one weed (non-native/ruderal/invasive) species over a four-year period after the installation of a 1.8 km livestock water pipeline and subsequent …


Human Dimensions Of Habitat Loss In The Plains And Prairie Potholes Ecoregion, Lily A. Sweikert Jan 2017

Human Dimensions Of Habitat Loss In The Plains And Prairie Potholes Ecoregion, Lily A. Sweikert

Electronic Theses and Dissertations

The Plains and Prairie Potholes Ecoregion (PPPE), is located in the north-central contiguous United States and is one of the most imperiled grassland regions in the world. Most of the region is privately owned and used for the production of agricultural commodities. In addition to its direct benefits to humanity, the PPPE provides multiple ecosystem services including, soil and water quality improvements, carbon sequestration, weather amelioration, and wildlife habitat. Recent increases in expansion of row crop agriculture concerns conservation practitioners about the long-term integrity of the PPPE. Conservation practitioners are looking to improve their private landowner conservation initiatives in the …


An Evaluation Of Nitrogen Supplementation And Processed Soy Fractions On The Performance Of Cultured Fishes, Brandon M. White Jan 2017

An Evaluation Of Nitrogen Supplementation And Processed Soy Fractions On The Performance Of Cultured Fishes, Brandon M. White

Electronic Theses and Dissertations

World population growth has resulted in an increased demand for a sustainable food supply. This rapid growth coupled with an increased per capita consumption of seafood, has resulted in many of the world’s marine fisheries being over-exploited in an effort to meet the global demand for seafood. Aquaculture has attempted to fill the supply and demand gap created by the dwindling supply of fish in the world’s oceans. Fishmeal (FM) has traditionally been the primary protein ingredient in aquafeeds fed to farm-raised fish, however its unstable supply and increasing price have driven researchers to identify alternative protein sources. Soybean meal …


Evaluation Of Gamebird Use And Thermal Characteristics Of Alfalfa And Perennial Grasses In Eastern South Dakota, Neal P. Martorelli Jan 2017

Evaluation Of Gamebird Use And Thermal Characteristics Of Alfalfa And Perennial Grasses In Eastern South Dakota, Neal P. Martorelli

Electronic Theses and Dissertations

The northern Great Plains provide critical breeding habitat for waterfowl and gamebirds in the United States. Peak commodity prices in the late 2000s resulted in increased agricultural production and large-scale conversions of grassland habitat to monoculture row crops. However, recent declines in commodity prices have created a renewed interest for private landowners to diversify crops and enroll in government subsidized conservation programs that convert idle grassland and unproductive cropland to wildlife friendly perennial grassland plantings. Exploring alternative grassland restoration techniques can improve the efficiency of management practices to benefit future wildlife habitat and productivity on both public and private lands. …


Effects Of A Large-Scale Habitat Enhancement Project On Largemouth Bass Behavior, Feeding, And Growth In Grand Lake, Texas, Chance Kirkeeng Jan 2017

Effects Of A Large-Scale Habitat Enhancement Project On Largemouth Bass Behavior, Feeding, And Growth In Grand Lake, Texas, Chance Kirkeeng

Electronic Theses and Dissertations

The quality of habitat, or the environment suitable for an organism to survive and reproduce, is often described by the type of features present and the quantity and condition of such features. Habitats in many ecosystems are declining and the loss of important habitats likely affects the success of organisms reliant upon those features. Habitats in reservoir ecosystems are especially at risk because of aging processes that are degrading reservoir habitats at faster rates than habitats in other ecosystems. Habitat enhancement projects are one tool used to combat the effects of aging reservoirs but the benefits of these management actions …


Invertebrate Prey Selectivity Of Channel Catfish (Ictalurus Punctatus) In Western South Dakota Prairie Streams, Erin D. Peterson Jan 2017

Invertebrate Prey Selectivity Of Channel Catfish (Ictalurus Punctatus) In Western South Dakota Prairie Streams, Erin D. Peterson

Electronic Theses and Dissertations

Benthic invertebrates are an important resource for aquatic consumers and should be considered in management of sportfish populations as a factor influencing fishery health. Our study seeks to draw a relationship between invertebrate prey availability and the Channel Catfish Ictalurus punctatus fishery of western South Dakota through diet analysis, but invertebrate surveys in the area have not focused on invertebrates as a prey source. Our objectives were to characterize patterns in availability of the invertebrate prey base in five major river basins, and to evaluate the effects of availability on Channel Catfish prey selectivity and condition. Invertebrates were collected at …


A Statewide Assessment Of Drivers Influencing Biotic Integrity In Perennial, Wadeable Prairie Streams Of South Dakota, Lyntausha Kuehl Jan 2017

A Statewide Assessment Of Drivers Influencing Biotic Integrity In Perennial, Wadeable Prairie Streams Of South Dakota, Lyntausha Kuehl

Electronic Theses and Dissertations

Biological assessments are used to evaluate the biotic integrity of a system. Great Plains prairie streams are harsh environments due to variable climate, topography, vegetation, and human development. This presents a challenge to water resource managers who must detect impairment and determine causation. The objectives of this study were: 1) to develop a macroinvertebrate Index of Biotic Integrity (IBI) for the Northwestern Great Plains (NWGP) and compare it to an existing Northern Glaciated Plains (NGP) IBI, and 2) to identify and evaluate statewide abiotic drivers of biotic integrity. The IBIs were hypothesized to differ regionally, as were abiotic drivers explaining …


Biotic Integrity In The Northwestern Great Plains And Mechanisms Regulating Stream Condition In South Dakota, Chad Kaiser Jan 2017

Biotic Integrity In The Northwestern Great Plains And Mechanisms Regulating Stream Condition In South Dakota, Chad Kaiser

Electronic Theses and Dissertations

Anthropogenic disturbance of streams can alter biotic integrity in various ways. Some degradation is easy to classify and monitor, others such as habitat impairment may be less easy to quantify. The Index of Biotic Integrity (IBI) is a unique method of assessing the aquatic health of an ecosystem. Beginning in 2010 the South Dakota Department of Environment and Natural Resources (SD DENR) began implementing biological monitoring on wadeable streams by developing an IBI for the Northern Glaciated Plains ecoregion in eastern SD (Krause et al. 2013). Prior to this survey the condition of the majority of SD’s streams was unknown. …


Development And Application Of A Fish-Based Index Of Biotic Integrity For Lakes In Eastern South Dakota, Daniel T. Nelson Jan 2017

Development And Application Of A Fish-Based Index Of Biotic Integrity For Lakes In Eastern South Dakota, Daniel T. Nelson

Electronic Theses and Dissertations

The Index of Biotic Integrity (IBI) was developed to summarize the impact of watershed and water quality degradation to biotic communities and help to provide a more complete picture of water quality changes that are not captured in traditional physical and chemical measurements. In 2014, nearly 15% of South Dakota lakes did not meet their designated beneficial uses based on water quality measures but the impacts to the fish communities are unknown. The goal of this study was to develop a fish-based IBI for eastern South Dakota lakes by addressing three specific objectives:
1) Determine whether an IBI could be …


Impacts Of Wetland Characteristics On Duck Use In The Prairie Pothole Region (Ppr) 1987-2013, Fred Thomas Oslund Jan 2016

Impacts Of Wetland Characteristics On Duck Use In The Prairie Pothole Region (Ppr) 1987-2013, Fred Thomas Oslund

Electronic Theses and Dissertations

Since 1987 the Waterfowl Breeding Populations and Production Estimates, also called the Four Square Mile Survey, has been conducted annually in the U.S. Prairie Pothole Region. The survey was designed to assess the influence of the Small Wetlands Acquisition Program on contributions to continental waterfowl populations (Cowardin et al. 1995). Each year cooperators visit sample wetlands during two survey periods, collecting data on observed waterfowl and pond conditions. Along with ground counts, aerial photography of sample areas is collected annually, capturing habitat conditions. My objective was to assess the influence of local and landscape factors on duck pair densities. Local …


The Ecological Significance Of Emerging Deltas In Regulated Rivers, Malia A. Volke, Michael L. Scott, W. Carter Johnson, Mark Dixon Apr 2015

The Ecological Significance Of Emerging Deltas In Regulated Rivers, Malia A. Volke, Michael L. Scott, W. Carter Johnson, Mark Dixon

Natural Resource Management Faculty Publications

Sedimentary deltas forming in the world’s regulated rivers are a glaring gap in our knowledge of dammed riverine ecosystems. Basic ecological information is needed to inform the current debate about whether deltas should be retained and managed to gain ecosystem services lost under reservoirs or whether they should be partially removed to improve flow conveyance and to resupply sediment-starved reaches below dams. An examination of nine deltas on the heavily regulated upper and middle Missouri River showed the following: The sizes, dynamics, and biotic communities vary widely across deltas; riparian forest has established on portions of most deltas; the current …


An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Bronc Mcmurtry Jan 2015

An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Bronc Mcmurtry

Electronic Theses and Dissertations

Four different grazing systems: two rotational, a continuous, and a high-intensity, short-duration (mob) system, replicated twice, were evaluated from an economic perspective. Mob grazing is defined as a system having very high stocking rates for a small amount of time. Livestock are forced to eat or trample the vegetation. Stocking rates and average daily gains (ADG) were collected from the UNL Barta Brothers ranch near Rose, Nebraska. The study started in 2011 and lasted until 2014. Using the performance data and other cost data relevant to South Dakota and Nebraska, budgets were set up for each system and extrapolated to …


Invasion Is Contingent On Species Assemblage And Invasive Species Identity Inexperimental Rehabilitation Plots, A. Joshua Leffler, Eamonn D. Leonard, Jeremy J. James, Thomas A. Monaco Nov 2014

Invasion Is Contingent On Species Assemblage And Invasive Species Identity Inexperimental Rehabilitation Plots, A. Joshua Leffler, Eamonn D. Leonard, Jeremy J. James, Thomas A. Monaco

Natural Resource Management Faculty Publications

Ecological studies often suggest that diverse communities are most resistant to invasion by exotic plants, but relatively few local species may be available to a rehabilitation practitioner. We examine the ability of monocultures and diverse assemblages to resist invasion by an exotic annual grass (cheatgrass) and an exotic biennial forb (dyer’s woad) in experimental rehabilitation plots. We constructed seven assemblages that included three monocultures of grass, forb, or shrub; three four-species mixtures of grasses, forbs, or shrubs; and a three-species mixture of one species from each growth form in an experimental field setting to test resistance to invasion. Assemblages were …


Evidence For 20th Century Climate Warming And Wetland Drying In The North American Prairie Pothole Region, Brett A. Werner, W. Carter Johnson, Glenn R. Guntenspergen Sep 2013

Evidence For 20th Century Climate Warming And Wetland Drying In The North American Prairie Pothole Region, Brett A. Werner, W. Carter Johnson, Glenn R. Guntenspergen

Natural Resource Management Faculty Publications

The Prairie Pothole Region (PPR) of North America is a globally important resource that provides abundant and valuable ecosystem goods and services in the form of biodiversity, groundwater recharge, water purification, flood attenuation, and water and forage for agriculture. Numerous studies have found these wetlands, which number in the millions, to be highly sensitive to climate variability. Here, we compare wetland conditions between two 30-year periods (1946–1975; 1976–2005) using a hindcast simulation approach to determine if recent climate warming in the region has already resulted in changes in wetland condition. Simulations using the WETLANDSCAPE model show that 20th century climate …


A Survey Of Aquatic Invertebrate Communities In Nebraska Sandhill Lakes Reveals Potential Alternative Ecosystem States, J.C. Jolley, E.S. Albin, M.A. Kaemingk, D.W. Willis Jun 2013

A Survey Of Aquatic Invertebrate Communities In Nebraska Sandhill Lakes Reveals Potential Alternative Ecosystem States, J.C. Jolley, E.S. Albin, M.A. Kaemingk, D.W. Willis

Natural Resource Management Faculty Publications

Aquatic invertebrate communities are important to shallow lake ecosystem form and function, providing vital components to the food web and thereby important to achieving lake management goals. We characterized lake invertebrate communities and physicochemical variables in six Nebraska Sandhill lakes and examined these characteristics within an alternative stable state framework. Surveys were conducted during 2005 within each of these lakes by sampling aquatic macroinvertebrate abundance, zooplankton abundance and biomass, phytoplankton biomass, and physicochemical variables. When placed within an alternative stable state framework, the response variables exhibited a gradient of different ecosystem states. Two lakes appeared congruent with the clear water …


Continuous, Pulsed And Disrupted Nutrient Subsidy Effects On Ecosystem Productivity, Stability, And Energy Flow, Michael J. Weber, Michael L. Brown Feb 2013

Continuous, Pulsed And Disrupted Nutrient Subsidy Effects On Ecosystem Productivity, Stability, And Energy Flow, Michael J. Weber, Michael L. Brown

Natural Resource Management Faculty Publications

Resource pulses and subsidies can supply ecosystems with an important source of nutrients that supports additional productivity at multiple trophic levels. Common carp Cyprinus carpio provide ecosystems with a continuous nutrient subsidy through bioturbation and excretion but may also initiate a nutrient pulse through carcass decomposition. We examined how continuous (common carp foraging and excretion), pulsed (carcass decomposition) and disrupted (carp introduced and then removed) nutrient subsidies differed in their ability to alter nutrient availability, ecosystem productivity and stability and energy flow. Nitrogen and phosphorus availability and primary production were highest in pulsed, intermediate in continuous and lowest for disrupted …