Digital Commons Network^™

Limited Rigor In Studies Of Raptor Mortality And Mitigation At Wind Power Facilities, Tara J. Conkling, Christopher J.W. Mcclure, Sandra Cuadros, Scott R. Loss, Todd E. Katzner

United States Geological Survey: Staff Publications

Wind power is an expanding source of renewable energy. However, there are ecological challenges related to wind energy generation, including collisions of wildlife with turbines. Lack of rigor, and variation in study design, together limit efforts to understand the broad-scale effects of wind power infrastructure on wildlife populations. It is not clear, however, whether these types of limitations apply to groups of birds such as raptors that are particularly vulnerable to negative effects of wind energy. We reviewed 672 peer-reviewed publications, unpublished reports, and citations from 321 wind facilities in 12 countries to evaluate methods used to monitor and mitigate …

Spatial Analysis Of Burn Severity And Streamflow Response In The Western Conus, Will Brendan Long

Dissertations and Theses

Wildfire increases the magnitude of runoff in catchments, which can lead to the degradation of ecosystems, risk to infrastructure, and loss of life. The Labor Day Fires of 2020 provided an opportunity to compare multiple large and severe wildfires with the objective of determining potential changes to hydrologic processes in Oregon Cascades watersheds. Geographic information systems (GIS) were implemented to determine the total percentage burned and percentage of high burn severity class of six watersheds on the west-slope of the Oregon Cascade Range. In addition, two control watersheds were included to contrast the influence of climatic effects. Spatial arrangement of …

Growth And Reproduction In Gulf Of Mexico Black Corals (Antipatharians) In Field And Laboratory Studies, Victoria E. Salinas

Theses and Dissertations

Black corals provide an important ecosystem of marine life and are found throughout all the oceans of the world at depths between 2 and 8,600 m. However, little is understood about their life history and the factors that control the distribution of black corals, particularly in the Gulf of Mexico (GoM). Given the impacts of the Deepwater Horizon oil spill on soft corals (e.g., black corals and octocorals) in the GoM, studies of their growth and reproductive biology in both natural and aquaculture environments are crucial for restoration efforts. The objectives of this study were to examine reproductive processes, compare …

The Current State Of Community Engagement In Urban Soil Pollution Science, Nicole Fernández-Viña, Yujuan Chen, Kirsten Schwarz

Agricultural and Environmental Sciences Faculty Research

Environmental burdens disproportionately impact the health of communities of color and low-income communities. Contemporary and legacy industry and land development may pollute soils with pesticides, petroleum products, and trace metals that can directly and indirectly impact the health of frontline communities. Past efforts to study environmental injustice have often excluded those most impacted, created distrust of researchers and other experts among frontline communities, and resulted in little to no structural change. Prevailing research methods value formal knowledge systems, while often dismissing the knowledge of those most harmed by environmental hazards. Community science has emerged as a process of doing science …

Rodent Dental Microwear Texture Analysis As A Proxy For Fine-Scale Paleoenvironment Reconstruction, Jenny H. E. Burgman

Graduate Theses and Dissertations

Dental microwear texture analysis (DMTA) of fossil fauna has become a valuable tool for dietary inference and paleoenvironment reconstruction. Most of this work has utilized larger taxa with larger home ranges. These studies may result in broader-scale habitat inferences that could mask the details of complex mosaic habitats. Rodent DMTA offers an opportunity to work at finer spatial scales because most species have smaller home ranges. Rodents are also keystone species within their ecosystems, abundant, ubiquitous, and found in many fossil deposits. These attributes make them excellent proxies for environmental reconstructions. However, the application of DMTA to rodents remains relatively …

Relationships Between Biodiversity And Production In Grasslands At Local And Regional Scales, A. Hector, M. Loreau

IGC Proceedings (1993-2023)

Key points

1. Experimental manipulations of plant species diversity in unfertilised prairies and meadows has revealed that increasing diversity often leads to increased productivity (range of observed relationships varies from flat to log-linearly positive); driven by a combination of facilitation, niche-partitioning and sampling/selection effects.

2. The longer-term effects of diversity on ecosystem stability are not as clear and in need of further work.

3. Recent applied work, and a new review of the grassland literature, both show the potential for biodiversity to increase productivity under realistic field conditions.

4. The longer-term feedback of grazers on biodiversity gradients is unknown, and …

Global Atmospheric Change And Its Effect On Managed Grassland Systems, Andreas Lüscher, J. Fuhrer, P. C. D. Newton

IGC Proceedings (1993-2023)

Key points

1. Increasing atmospheric CO2 concentration and a trend to warmer mean temperatures are the most reliable aspects of global atmospheric change. Projections of the extent of climate change and the frequency of extreme weather conditions remain uncertain.

2. Research has considerably reduced the uncertainty about effects of global atmospheric change on physiology of plants, productivity and species composition of plant communities.

3. Other factors (e.g. nutrient availability, soil type) and long-term adaptation of the ecosystem (e.g. nutrient cycling and sequestration) influence the response of plant communities to global atmospheric change. Generalisation is not possible with respect to the …

Potential Of C4 Tropical Grasses To Contribute In Carbon Sequestration, Environmental Security And Livelihood Opportunities Through Increased Fodder Availability, D. R. Malaviya, A. K. Roy, P. Kaushal

IGC Proceedings (1993-2023)

The world grasslands/rangeland ecosystems comprise 26% of earth’s surface and have immense ecological and economic significance. Diversity of grasslands had been a key element for their sustainability. Grasslands in India have existed as natural ecosystems for millions of years. It is a major source of income, employment and livelihood to the rural families. Owing to heavy grazing pressure, coupled with other social/anthropogenic factors, the grazing resources have fast deteriorated. The country has many old and natural grasslands with ethnic and economic value. Comprehensive ecological studies including floristic compositions, dominant species, grazing pressure and the climax/sub-climax stages of ecological succession will …

Forb Counts In Grassland Are Sensitive To Analytical Method, Gene A. Fults

IGC Proceedings (1993-2023)

An analysis of forbs from 9 years of Plant Census protocol (NRI 2019) is compared to data from the Line Point Intercept (LPI) protocol. Both protocols were conducted on the same geospatially separate macroplots (N=1230). The macroplots locations were stratified by NRI based on a land hierarchy which has had long-term use in the United States (Salley etal 2015). This ties vegetation and land together in the data. The analysis showed that the 15-minute plant census method increased forb species data by 29 percent over the LPI method which takes 40-60 minutes. Both methods captured similar total ratios and rank …

Characterizing Invasiveness Through A Descriptive Study Of Guinea Grass (Megathyrsus Maximus) Growing In Three Habitat Types And Differing Herbivore Assemblages In Both Kenya And Texas, A. C. Rhodes, R. M. Plowes, D. J. Martins, I. Ng'iru, L. E. Gilbert

IGC Proceedings (1993-2023)

Guinea grass (Megathyrsus maximus syn. Panicum maximum) is an important pasture grass that has been introduced pantropically, yet in many cases has escaped cultivation and is invading native rangelands – threatening biodiversity at multiple trophic levels. An increasing challenge of rangeland management is balancing the importance of pasture grasses with their negative impact on ecosystem processes. Given this challenge, it is critical to understand the mechanisms that underlie grass invasion. In this descriptive study, our objective was to assess the ecological stress release hypothesis by comparing the relative abundance and functional traits of Guinea grass in Kenya's home …

An Integrated Framework To Study Ecological Tipping Points In Social-Ecological Systems, F. A. Männer, L.-M. Schwarz, D. A. Menestrey-Schwieger, V. Amputu, M. C. Bilton, K. Brinkmann, G. Dressler, N. Hamunyela, H. Heita, S. Heshmati, S. Liehr, M. Mbidzo, F. Munyebvu-Chambara, W. C. Nesongano, M. Rauchecker, A. Sandhage-Hofmann, K. Tielbörger, K. Zimmer, A. Linstädter

IGC Proceedings (1993-2023)

Sudden regime shifts or tipping points pose a major threat to various ecosystems and people's livelihoods worldwide. However, tipping points are still hard to predict and often occur without warning. To avoid dramatic social-ecological consequences, it is crucial to understand tipping point behaviour and to identify early warning indicators. Previous studies have hardly implemented an integrated social-ecological approach, which has led to a fragmented understanding and oversimplification of tipping point phenomena. Against this background, we present a systemic research framework that harmonizes ecological and social perspectives to gain a mechanistic understanding of tipping point behaviour. We utilize a social-ecological systems …

Lake Huron Shoreline Analysis, Shubham Satish Nandanwar

Theses and Dissertations (Comprehensive)

Lake Huron is a popular tourist destination and is home to several businesses and residents. Since the shoreline is dynamic and is subject to change over the years due to several factors such as a change in water level, soil type, human encroachment, etc., these locations tend to encounter floods due to increased water levels and wind speed. This causes erosion and loss to the properties along the shoreline.

This study is based on two areas of interest named Pinery Provincial Park and Sauble Beach which are located on the shoreline of Lake Huron where Pinery Provincial Park is a …

Biotic Characteristics Of Managed And Unmanaged Coastal Dunes In The Outer Banks, North Carolina, Andrew E. White

Theses and Dissertations

Under future climate change and sea level rise scenarios, Natural and Nature-Based Features (e.g., dunes) that protect coastal habitat and infrastructure will be exposed to increased wave energy and storm surge. Understanding how these forces will impact coastal dunes is necessary for their continued use as protective features. Coastal dunes develop through feedback between vegetation and sediment deposition, a process complicated by species-specific growth rates and responses to burial. Wave flume studies have tested the effects of dune vegetation on erosion and found multiple plant organs across several functional types to be important for resisting erosion. Although dune building and …

Elements Of Biocontrol Strategies For Pheretimoid Earthworms, Maryam Nouri-Aiin

Graduate College Dissertations and Theses

Jumping worms (Megascolecidae) in the pheretimoid complex, have raisedconsiderable environmental concerns with conservationists, ecologists, policy makers, and the public. Their impacts on North American forests and high density is distinct from earthworms in other families. Most of the infested forests are near horticultural settings. Practicable options to manage their dispersal into forests do not exist. This dissertation examines the potential of an entomopathogenic fungus to control them in horticulture. It also investigates major barriers to managing their spread and studying their ecology including species identification, phenology, and genetic diversity. First, to discover the best time to apply biocontrol agents, I …

Study Of The Diversity Of Soil Animals Community In The Songnen Plain Grassland Of China, Xiuqin Yin, Tingcheng Zhu

IGC Proceedings (1993-2023)

This paper dealt with the diversity in eight habitat soil animals communities in Songnen plain grassland. The results showed the better habitat condition the higher diversity index of soil animals, and vice-versa. The diversity of soil animals communities correlated positively with soil organic matter, total nitrogen, and negatively with soil pH; there was a poor correlation with soil water content and total soil phosphorus. The diversity of soil animals communities decreased with increasing depth of soil layer and has surface-collection.

Biodiversity And Fire In Shortgrass Steppe, Paulette L. Ford

IGC Proceedings (1993-2023)

Effects of fire at two levels of intensity on beetle diversity in shortgrass steppe were examined. The experimental design was completely randomized, with 3 treatments and 4 replicates per treatment. Treatments were two levels of fire 1) dormant-season fire (relatively hot), and 2) growing-season fire (relatively cool), and unburned plots. The response variables were arthropod species richness and abundance. The intermediate disturbance hypothesis predicts that maximum species richness occurs at intermediate levels of disturbance. Data obtained in this study support that prediction. Species richness was higher on plots of intermediate fire intensity than the more intensely burned plots, and almost …

Exploring Hydrologic Responses To Different Wildfire Spatial Patterns Through The Lens Of Computational Modeling, Luke M. Telfer

Boise State University Theses and Dissertations

Severe wildfire disturbances are becoming increasingly common in high-elevation forests of the western United States. These fires alter watershed hydrologic processes, threatening critical downstream water resources and aquatic ecosystems. However, watershed-scale postfire hydrologic responses and water balance changes are highly uncertain. While postfire effects on individual processes such as runoff, infiltration, evapotranspiration, and snow dynamics are relatively well known, the role of wildfire spatial patterns in governing hydrologic connectivity and interactions between water balance components is poorly understood due to challenges associated with measuring and comparing fires at large scales. This thesis aims to examine pattern-related postfire interactions between various …

The Legume – Rhizobia Symbiosis. Does It Vary For The Tropics Relative To The Mediterranean Basin?, J. G. Howieson, A. Mcinnes

IGC Proceedings (1993-2023)

Symbiotic N fixation from legumes is one of the most important biological processes on the planet. It currently provides the majority of the N requirement in agriculture, yet will have to double if cereal crop production is to meet world demand by 2020 (Kennedy and Cocking 1997). To effectively harness the value of biological N fixation from legumes we need to more fully understand G² x E; where G refers to the genotypes of both the legume (G_l) and its microsymbiont (rhizobia; G_r), and E refers to the edaphic environment in which the symbiosis is …

Agronomic Evaluation Of Alfalfa Cultivars In Rio Grande Do Sul, Brasil, J. C. De Saibro, R. Battisti, T. M. S. Freitas

IGC Proceedings (1993-2023)

From April 1995 to June 1998, thirty five alfalfa (Medicago sativa L.) cultivars (cvs.) were evaluated in a field trial at the “Depressão Central” ecoclimatic region, in southern Brazil. Two years after sowing, 30 cultivars were excluded from the test due to their poor overall agronomic performance, mainly low forage DM yields. The remaining cultivars: Crioula (local genotype used as a check), Victoria, Rio and P 30 are hay-type cultivars while Alfagraze is a grazing-tolerant type. Twenty-two harvests were made and no significant differences were found for total DM yields among cvs. Crioula, Victoria, Rio and P 30; however, …

Amphicarpy In The Tropical Legume Centrosema Rotundifolium: A Research Project In Eastern Venezuela, S. Müller, R. Schultze-Kraft, I. Rodríguez

IGC Proceedings (1993-2023)

Amphicarpy is a particular reproduction mechanism by which a plant can produce both above-ground and below-ground seeds and thus has the potential to contribute to an enhanced persistence of a plant population. It can be found in a range of tropical legumes, e.g. in several Centrosema species. The balance between above- and below-ground seed production is evidently influenced by environment and management factors but these influences are not well known. In the case of perennial tropical legumes, in addition to seed production shifts the allocation of resources affects also the production of tuberous roots as storage organs. A research project …

Knowledge About And Knowledge With: Contributions From Feminist Research To Knowledge Co-Production For Pastoral Systems, F. Ravera, María Fernández-Giménez, E. Oteros-Rozas

IGC Proceedings (1993-2023)

Globally, the gender dynamics of rangeland social-ecological systems have received scant attention. Further, research paradigms, methods and methodologies that leave little room for equitable engagement with research participants and genuine action-oriented research-practice partnerships dominate in pastoralist/rangeland studies. Our research is informed by a feminist philosophy of science and based on decolonial and feminist political ecology studies that focus on gendered science and knowledge production. Feminist research calls for reflection on who produces knowledge and how such knowledge is used and shared. Feminist practices such as reciprocity, care, and positionality, cultivate awareness of the power dynamics embedded in the research process …

Soil Microbial Carbon, Nitrate And Ammonium Nitrogen Dynamics In Urochloa Grass Cultivated In Sub-Humid Kenya, K. W. Ndung’U-Magiroi, M. N. Koech, M. C. Mutoko, M. Kamidi, Elias M. Gichangi, Donald M. G. Njarui

IGC Proceedings (1993-2023)

A study was conducted to monitor the dynamics of available soil phosphorus (P), soil microbial biomass carbon (SMBC), nitrogen (SMBN), ammonium and nitrate nitrogen under seven Urochloa grass cultivars at Kitale, Kenya. The Urochloa cultivars: Urochloa brizantha cvs. Marandu, MG-4, Piata, Xaraes, U. decumbens cv. Basilisk, U. hybrid cv. Mulato II and U. humidicola cv. Llanero was compared with two popularly grown forages, Rhodes grass (Chloris gayana cv. KAT R3), Napier grass (Pennisetum purpureum cv. KK1) and annual weeds. The treatments were tested in a randomized complete block design arranged in a split plot treatment structure with two …

Climate Smart Urochloa Grasses Improves Soil Health In The Semi-Arid Tropics Of Kenya, Elias M. Gichangi, Donald M. G. Njarui, Mwangi Gatheru

IGC Proceedings (1993-2023)

The measurement of soil aggregates stability and soil microbial biomass can be used as an early indicator of long-term changes in soil quality. A study was conducted to quantify the amounts of shoots and roots biomass of Urochloa grass cultivars (commonly known as Brachiaria) and their effects on changes in the size distribution and stability of soil aggregates and on microbial biomass carbon (C), nitrogen (N) and phosphorus (P) in a structurally unstable sandy loam soil at Ithookwe and Katumani in semi-arid tropical Kenya. The Urochloa grass cultivars included Urochloa decumbens cv. Basilisk, U. brizantha cvs Marandu, MG-4, Piatã and …

Spittlebugs: Bioecology, Host Plant Resistance And Advances In Ipm, José R. Valério, C. Cardona, D. C. Peck, G. Sotelo

IGC Proceedings (1993-2023)

Several species and genera of spittlebugs (Homoptera: Cercopidae) are economic pests of grasses in tropical America. These insects compete with grazing animals by reducing forage availability and quality. They may cause serious losses on millions of hectares of improved pastures based on cultivars of several species of Brachiaria (signal grasses). Except for the cultivar Marandu, most of the available commercial cultivars of Brachiaria are susceptible to spittlebugs. In spite of their economic importance, much research need to be done yet. Such insect-plant system encompasses a diverse group of spittlebug species, a diverse group of forage grass species, which are under …

Nutrient Dynamics And Inventory In Tropical Grassland Ecosystem In Southern India, K. Karunaichamy, Kailash Paliwal

IGC Proceedings (1993-2023)

The present study was to ascertain the distribution of calcium (Ca), magnesium (Mg) and sodium (Na) in the different plant components and in the soil top 30 cm at Kalikesam in Western Ghats region of southern India. Magnesium concentration increased in the order: dead shoots > belowground > litter > aboveground live. Sodium concentration in live shoots was maximum in February (0.51%) and minimum in August (0.05%). Annually 8.94 g/m² Ca, 2.41g/ m² Mg and 2.30g/ m² Na was taken up by plants. The distribution of the three nutrients in plant/soil system indicated that the major portion of the nutrients …

Production Potential Of South America Grasslands, G. E. Maraschin

IGC Proceedings (1993-2023)

Grasslands exist all over the world under a wide range of climates, soil types, topography conditions and seasonality. The South America grasslands cover a wide range of ecosystems and vegetaion types, going from desert areas to steppes, subhumid temperate, subtropical and tropical savannas embodying also portions of the tropical rain forest environment, and represent one of the Earth’s largest expanses of natural rangelands (Oesterheld et al., 1992). They represent developed ecosystems requiring acquaintance to accept sound agronomic and ecological activities. The diversity of vegetation determined by the latitudes 6^oN, down to the southern most tip of the continent …

Matching Up The Complexity Of Grassland Of Inner Mongolia — On The Methodology Issues, Yisheng Zheng

IGC Proceedings (1993-2023)

No abstract provided.

Multiple Use Management On Canadian Publicly Managed Rangeland, B. Kirychuk, R. Gaube, S. Kushreshtha, G. Pearson

IGC Proceedings (1993-2023)

No abstract provided.

Effects Of Acid Deposition And Changing Climate On The Hydrochemistry And Critical Loads Of Watersheds In The Adirondack Region Of New York, Shuai Shao

Dissertations - ALL

Despite decreases in acidic deposition since the 1970s, the recovery of surface waters from acidification has been limited primarily due to the depletion of exchangeable base cations, net mineralization of organic sulfur and nitrogen and release of previously retained SO42- and NO3-, and increases in concentrations of naturally occurring organic acids from soil. The future recovery of stream chemistry from acidic deposition may be altered by projected increases in temperature and precipitation associated with a changing climate. The goals of this study were to conduct a modeling analysis of the response of soils and streams in the Adirondack Park, New …

Months-Long Spike In Aqueous Arsenic Following Domestic Well Installation And Disinfection: Short- And Long-Term Drinking Water Quality Implications, M. L. Erickson, E. D. Swanner, Brady A. Ziegler, J. R. Havig

Geosciences Faculty Research

Exposure to high concentration geogenic arsenic via groundwater is a worldwide health concern. Well installation introduces oxic drilling fluids and hypochlorite (a strong oxidant) for disinfection, thus inducing geochemical disequilibrium. Well installation causes changes in geochemistry lasting 12 + months, as illustrated in a recent study of 250 new domestic wells in Minnesota, north-central United States. One study well had extremely high initial arsenic (1550 µg/L) that substantially decreased after 15 months (5.2 µg/L). The drilling and development of the study well were typical and ordinary; nothing observable indicated the very high initial arsenic concentration. We hypothesized that oxidation of …