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Full-Text Articles in Life Sciences

18s-Nemabase: Curated 18s Rrna Database Of Nematode Sequences, Kaitlin Gattoni, Eli M. S. Gendron, Rebeca Sandoval- Ruiz, Abigail Borgemeier, J. Parr Mcqueen, Rachel M. Shepherd, Dieter Slos, Tom Powers, Dorota L. Porazinska Aug 2022

18s-Nemabase: Curated 18s Rrna Database Of Nematode Sequences, Kaitlin Gattoni, Eli M. S. Gendron, Rebeca Sandoval- Ruiz, Abigail Borgemeier, J. Parr Mcqueen, Rachel M. Shepherd, Dieter Slos, Tom Powers, Dorota L. Porazinska

Department of Plant Pathology: Faculty Publications

Nematodes are the most abundant and diverse animals on the planet but lack representation in biodiversity research. This presents a problem for studying nematode diversity, particularly when molecular tools (i.e., barcoding and metabarcoding) rely on well-populated and curated reference databases, which are absent for nematodes. To improve molecular identification and the assessment of nematode diversity, we created and curated an 18S rRNA database specific to nematodes (18S-NemaBase) using sequences sourced from the most recent publicly available 18S rRNA SILVA v138 database. As part of the curation process, taxonomic strings were standardized to contain a fixed number of taxonomic ranks relevant …


18s-Nemabase: Curated 18s Rrna Database Of Nematode Sequences, Kaitlin Gattoni, Eli M. S. Gendron, Rebeca Sandoval- Ruiz, Abigail Borgemeier, J. Parr Mcqueen, Rachel M. Shepherd, Dieter Slos, Tom Powers, Dorota L. Porazinska Aug 2022

18s-Nemabase: Curated 18s Rrna Database Of Nematode Sequences, Kaitlin Gattoni, Eli M. S. Gendron, Rebeca Sandoval- Ruiz, Abigail Borgemeier, J. Parr Mcqueen, Rachel M. Shepherd, Dieter Slos, Tom Powers, Dorota L. Porazinska

Department of Plant Pathology: Faculty Publications

Nematodes are the most abundant and diverse animals on the planet but lack representation in biodiversity research. This presents a problem for studying nematode diversity, particularly when molecular tools (i.e., barcoding and metabarcoding) rely on well-populated and curated reference databases, which are absent for nematodes. To improve molecular identification and the assessment of nematode diversity, we created and curated an 18S rRNA database specific to nematodes (18S-NemaBase) using sequences sourced from the most recent publicly available 18S rRNA SILVA v138 database. As part of the curation process, taxonomic strings were standardized to contain a fixed number of taxonomic ranks relevant …


Nematode Biodiversity In Lincoln, Nebraska's Tallgrass Prairie Corridor, Abigail Borgmeier Aug 2021

Nematode Biodiversity In Lincoln, Nebraska's Tallgrass Prairie Corridor, Abigail Borgmeier

Department of Plant Pathology: Dissertations, Theses, and Student Research

The tallgrass prairie was once one of the most diverse grasslands on the planet, however over 95% has been converted to agriculture in the past 150 years. The remaining prairie is still host to a wide variety of plants, insects, mammals, and soil-dwelling microorganisms, creating an incredibly complex ecosystem. The first aim of this study is to compare three approaches for the measurement of nematode diversity within a 10-mile-long protected prairie habitat corridor near Lincoln, Nebraska. The methods are 1) a traditional morphological analysis of 150 nematodes per study site, 2) a metabarcoding analysis using the 18S genetic marker of …


Food System And Water–Energy–Biodiversity Nexus In Nepal: A Review, Roshan Subedi, Madhav Karki, Dinesh Panday Aug 2020

Food System And Water–Energy–Biodiversity Nexus In Nepal: A Review, Roshan Subedi, Madhav Karki, Dinesh Panday

Department of Agronomy and Horticulture: Faculty Publications

Water, energy, and biodiversity are essential components for building a sustainable food system in a developing country like Nepal. Green Revolution technologies and the package of practices largely ignored the role of ecosystem services, leaving a large population of small farmers’ food- and nutrition-insecure. Biodiversity, especially, agrobiodiversity is in decline and this vital cross-cutting element is less discussed and interlinked in nexus literature. The interlinking food system with water–energy–biodiversity nexus, therefore, is essential to achieve a resilient food system. It ensures the vital structures and functions of the ecosystem on which it is dependent are well protected in the face …


Science At Engineer Cantonment, Hugh H. Genoways, Brett C. Ratcliffe, Carl R. Falk, Thomas E. Labedz, Paul R. Picha, John R. Bozell Jan 2018

Science At Engineer Cantonment, Hugh H. Genoways, Brett C. Ratcliffe, Carl R. Falk, Thomas E. Labedz, Paul R. Picha, John R. Bozell

University of Nebraska State Museum: Mammalogy Papers

Conclusions

It is our contention that Thomas Say, Titian Peale, Edwin James, and their colleagues of the Stephen Long Expedition of 1819–1820 were heavily engaged in scientific research, which took the form of the first biodiversity inventory undertaken in the United States. This accomplishment has been overlooked both by biologists and historians, but it should rank among the most significant accomplishments of the expedition. The results of this inventory continue to inform us today about environmental, faunal, and floral changes along the Missouri River in an area that is known to be an ecotone between the deciduous forests of the …


Historical Observations And Identifications Of Plants And Animals In The Vicinity Of Engineer Cantonment In 1819-1820, Hugh H. Genoways, Brett C. Ratcliffe, Carl R. Falk, John R. Bozell Jan 2018

Historical Observations And Identifications Of Plants And Animals In The Vicinity Of Engineer Cantonment In 1819-1820, Hugh H. Genoways, Brett C. Ratcliffe, Carl R. Falk, John R. Bozell

University of Nebraska State Museum: Mammalogy Papers

Historical observations and identifications of plants and animals in the vicinity of Engineer Cantonment in 1819–1820 (James 1822) are shown below in Roman and Roman italic print. Specimens identified through phytoarcheological and zooarcheological analysis of materials and believed to be reasonably associated or contemporaneous with the Long Expedition use of the site (AU4) are shown in boldface. Species present in both the historical and archeological data are marked by an asterisk (*). References used in this compilation include Benedict (1996), Brewer (1970 [1840]), Conant and Collins (1991), Ducey (2000), Evans (1997), Falk et al. (this volume), Genoways et al. (2008), …


The Significance Of Micro-Prairie Reconstruction In Urban Environments, Bruno Borsari, Neal Mundahl, Malcom F. Vidrine, Marc Pastorek Aug 2014

The Significance Of Micro-Prairie Reconstruction In Urban Environments, Bruno Borsari, Neal Mundahl, Malcom F. Vidrine, Marc Pastorek

The Prairie Naturalist

An aggressive urban sprawl during the last half century has not only contributed to habitat disturbance and extirpation, as well as a loss of knowledge and appreciation for biodiversity. Across the United States, prairie reconstruction has been a very effective approach for developing sustainable landscape designs in city parks and other open spaces. The purpose of this work is to focus on restoration and reconstruction of selected micro-prairies as a vehicle for enhanced place-based education and to partially remediate the consequences of global climate change and loss of pollinators. From the coastal prairies of southwestern Louisiana, to the eastern edge …


Housing Development Erodes Avian Community Structure In U.S. Protected Areas, Eric M. Wood, Anna M. Pidgeon, Volker C. Radeloff, David Helmers, Patrick D. Culbert, Nicholas S. Keuler, Curtis H. Flather Jan 2014

Housing Development Erodes Avian Community Structure In U.S. Protected Areas, Eric M. Wood, Anna M. Pidgeon, Volker C. Radeloff, David Helmers, Patrick D. Culbert, Nicholas S. Keuler, Curtis H. Flather

USDA Forest Service / UNL Faculty Publications

Protected areas are a cornerstone for biodiversity conservation, but they also provide amenities that attract housing development on inholdings and adjacent private lands. We explored how this development affects biodiversity within and near protected areas among six ecological regions throughout the United States. We quantified the effect of housing density within, at the boundary, and outside protected areas, and natural land cover within protected areas, on the proportional abundance and proportional richness of three avian guilds within protected areas. We developed three guilds from the North American Breeding Bird Survey, which included Species of Greatest Conservation Need, land cover affiliates …


Performance Of Species Richness Estimators Across Assemblage Types And Survey Parameters, Gordon C. Reese, Kenneth R. Wilson, Curtis H. Flather Jan 2014

Performance Of Species Richness Estimators Across Assemblage Types And Survey Parameters, Gordon C. Reese, Kenneth R. Wilson, Curtis H. Flather

USDA Forest Service / UNL Faculty Publications

Aim A raw count of the species encountered across surveys usually underestimates species richness. Statistical estimators are often less biased. Nonparametric estimators of species richness are widely considered the least biased, but no particular estimator has consistently performed best. This is partly a function of estimators responding differently to assemblage-level factors and survey design parameters. Our objective was to evaluate the performance of raw counts and nonparametric estimators of species richness across various assemblages and with different survey designs.

Location We used both simulated and published field data.

Methods We evaluated the bias, precision and accuracy of raw counts and …


The Influence Of Vertical And Horizontal Habitat Structure On Nationwide Patterns Of Avian Biodiversity, Patrick D. Culbert, Volker C. Radeloff, Curtis H. Flather, Josef M. Kellndorfer, Chadwick D. Rittenhouse, Anna M. Pidgeon Jan 2013

The Influence Of Vertical And Horizontal Habitat Structure On Nationwide Patterns Of Avian Biodiversity, Patrick D. Culbert, Volker C. Radeloff, Curtis H. Flather, Josef M. Kellndorfer, Chadwick D. Rittenhouse, Anna M. Pidgeon

USDA Forest Service / UNL Faculty Publications

With limited resources for habitat conservation, the accurate identification of high-value avian habitat is crucial. Habitat structure affects avian biodiversity but is difficult to quantify over broad extents. Our goal was to identify which measures of vertical and horizontal habitat structure are most strongly related to patterns of avian biodiversity across the conterminous United States and to determine whether new measures of vertical structure are complementary to existing, primarily horizontal, measures. For 2,546 North American Breeding Bird Survey routes across the conterminous United States, we calculated canopy height and biomass from the National Biomass and Carbon Dataset (NBCD) as measures …


Carrying Capacity For Species Richness As A Context For Conservation: A Case Study Of North American Breeding Birds, Andrew J. Hansen, Linda Bowers Phillips, Curtis H. Flather, Jim Robinson-Cox Jan 2011

Carrying Capacity For Species Richness As A Context For Conservation: A Case Study Of North American Breeding Birds, Andrew J. Hansen, Linda Bowers Phillips, Curtis H. Flather, Jim Robinson-Cox

USDA Forest Service / UNL Faculty Publications

Aim To demonstrate that the concept of carrying capacity for species richness (SK) is highly relevant to the conservation of biodiversity, and to estimate the spatial pattern of SK for native landbirds as a basis for conservation planning.

Location North America.

Methods We evaluated the leading hypotheses on biophysical factors affecting species richness for Breeding Bird Survey routes from areas with little influence of human activities.We then derived a best model based on information theory, and used this model to extrapolate SK across North America based on the biophysical predictor variables. The predictor variables included the …


Importance Of Myxomycetes In Biological Research And Teaching, Harold W. Keller, Sydney E. Everhart Jan 2010

Importance Of Myxomycetes In Biological Research And Teaching, Harold W. Keller, Sydney E. Everhart

Department of Plant Pathology: Faculty Publications

Myxomycetes, the true slime molds, are highlighted in research and teaching that emphasizes various stages of the life cycle as experimental models. Past and current phylogenetic classifications of Myxomycetes on the tree of life are presented. Life cycle stages are illustrated, described, and discussed. Simple laboratory demonstrations and experiments are described that include spore germination, spore release, and moist chamber cultures utilizing organic matter from various microhabitats. Novel compounds isolated from fruiting bodies and plasmodia of 22 myxomycete species are tabulated, some of which exhibit biological activity that function as antibiotics, antimicrobials, and are cytotoxic to cancer cells. Aeroallergens include …


Increased Weed Diversity, Density And Above-Ground Biomass In Long-Term Organic Crop Rotations, Samuel E. Wortman, John L. Lindquist, Milton J. Haar, Charles A. Francis Jan 2010

Increased Weed Diversity, Density And Above-Ground Biomass In Long-Term Organic Crop Rotations, Samuel E. Wortman, John L. Lindquist, Milton J. Haar, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

While weed management is consistently a top priority among farmers, there is also growing concern for the conservation of biodiversity. Maintaining diverse weed communities below bioeconomic thresholds may provide ecosystem services for the crop and the surrounding ecosystem. This study was conducted to determine if weed diversity, density and biomass differ within and among organic and conventional crop rotations. In 2007 and 2008, we sampled weed communities in four long-term crop rotations near Mead, Nebraska, United States using seedbank analyses (elutriation and greenhouse emergence) and above-ground biomass sampling. Two conventional crop rotations consisted of a corn (Zea mays) …


Farmers And Nature Conservation: What Is Known About Attitudes, Context Factors And Actions Affecting Conservation?, Johan Ahnström, Jenny Höckert, Hanna L. Bergea, Charles A. Francis, Peter Skelton, Lars Hallgren Jan 2009

Farmers And Nature Conservation: What Is Known About Attitudes, Context Factors And Actions Affecting Conservation?, Johan Ahnström, Jenny Höckert, Hanna L. Bergea, Charles A. Francis, Peter Skelton, Lars Hallgren

Department of Agronomy and Horticulture: Faculty Publications

Farmers’ attitudes towards viability of specific conservation practices or actions strongly impact their decisions on adoption and change. This review of ‘attitude’ information reveals a wide range of perceptions about what conservation means and what the impacts of adoption will mean in economic and environmental terms. Farmers operate in a tight financial situation, and in parts of the world they are highly dependent on government subsidies, and cannot afford to risk losing that support. Use of conservation practices is most effective when these are understood in the context of the individual farm, and decisions are rooted in land and resource …


Characterization Of Biological Types Of Cattle: Indicator Traits Offertility In Beef Cows, R. A. Cushman, M. F. Allan, L. A. Kuehn Jan 2008

Characterization Of Biological Types Of Cattle: Indicator Traits Offertility In Beef Cows, R. A. Cushman, M. F. Allan, L. A. Kuehn

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Genetic diversity among breeds of cattle allows producers to select animals for specific environments or market conditions. Reproductive efficiency is a multi-component trait that is largely influenced by environmental influences such as health and nutritional status; however, there are clearly genetic components to reproductive efficiency, and breed differences in a number of indicator traits associated with fertility and cow productivity have been identified. Historical indicators of fertility include scrotal circumference, age at puberty, and postpartum interval. Both age at puberty and postpartum interval are laborious traits to collect in heifers and cows because they require many days of detection of …


Effects Of Agricultural Conservation Practices On Fish And Wildlife Volume 2, Stuart R. Gagnon, Joseph R. Makuch, Cassandra Y. Harper Jan 2008

Effects Of Agricultural Conservation Practices On Fish And Wildlife Volume 2, Stuart R. Gagnon, Joseph R. Makuch, Cassandra Y. Harper

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

This bibliography, in two volumes, is part of a multi-volume set developed by the Water Quality Information Center at the National Agricultural Library in support of the United States Department of Agriculture’s Conservation Effects Assessment Project (CEAP). The bibliography is a guide to recent scientific literature covering effects of agricultural conservation practices on fish and wildlife. The citations listed here provide information on how conservation programs and practices designed to improve fish and wildlife habitat, as well as those intended for other purposes, e.g., water quality improvement, affect various aquatic and terrestrial fauna.


Effects Of Agricultural Conservation Practices On Fish And Wildlife, Stuart R. Gagnon, Joseph R. Makuch, Cassandra Y. Harper Jan 2008

Effects Of Agricultural Conservation Practices On Fish And Wildlife, Stuart R. Gagnon, Joseph R. Makuch, Cassandra Y. Harper

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

This bibliography, in two volumes, is part of a multi-volume set developed by the Water Quality Information Center at the National Agricultural Library in support of the U.S. Department of Agriculture’s Conservation Effects Assessment Project (CEAP). The bibliography is a guide to recent scientific literature covering effects of agricultural conservation practices on fish and wildlife. The citations listed here provide information on how conservation programs and practices designed to improve fish and wildlife habitat, as well as those intended for other purposes, e.g., water quality improvement, affect various aquatic and terrestrial fauna.


Predicting Plant Extinction Based On Species-Area Curves In Prairie Fragments With High Beta Richness, Brian J. Wilsey, Leanne M. Martin, H. Wayne Polley Jan 2005

Predicting Plant Extinction Based On Species-Area Curves In Prairie Fragments With High Beta Richness, Brian J. Wilsey, Leanne M. Martin, H. Wayne Polley

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Species-area relationships and island biogeography theory are commonly used to predict how species richness will decline with fragmentation. There are a variety of largely untested assumptions in these approaches, including the assumptions that populations are distributed uniformly before fragmentation, and that local extinctions are due to effects of small population sizes. If populations are not distributed uniformly, then populations can be abundant locally but rare globally. This would cause extinction rates to be smaller than predicted.We tested extinction theory by developing estimates of the number of plant species that should be present in small tallgrass prairie fragments and then testing …