Life Sciences Commons^™

Remote Sensing Of Forests Using Discrete Return Airborne Lidar, Hamid Hamraz, Marco A. Contreras

Forestry and Natural Resources Faculty Publications

Airborne discrete return light detection and ranging (LiDAR) point clouds covering forested areas can be processed to segment individual trees and retrieve their morphological attributes. Segmenting individual trees in natural deciduous forests, however, remained a challenge because of the complex and multi-layered canopy. In this chapter, we present (i) a robust segmentation method that avoids a priori assumptions about the canopy structure, (ii) a vertical canopy stratification procedure that improves segmentation of understory trees, (iii) an occlusion model for estimating the point density of each canopy stratum, and (iv) a distributed computing approach for efficient processing at the forest level. …

Challenges In Characterizing The Environmental Fate And Effects Of Carbon Nanotubes And Inorganic Nanomaterials In Aquatic Systems, Peter Laux, Christian Riebeling, Andy M. Booth, Joseph D. Brain, Josephine Brunner, Cristina Cerrillo, Otto Creutzenberg, Irina Estrela-Lopis, Thomas Gebel, Gunnar Johanson, Harald Jungnickel, Heiko Kock, Jutta Tentschert, Ahmed Tlili, Andreas Schäffer, Adriënne J. A. M. Sips, Robert A. Yokel, Andreas Luch

Pharmaceutical Sciences Faculty Publications

The current lack of commonly used protocols for dispersion, characterization, and aquatic toxicity testing of nanomaterials (NMs) has resulted in inconsistent results, which make meaningful comparisons difficult. The need for standardized sample preparation procedures that allow the reproducible generation of relevant test conditions remains a key challenge for studies of the environmental fate and aquatic toxicity of NMs. Together with the further development of optimized and cost-effective analytical techniques for physicochemical characterization that depend on reproducible sample preparation, such methods have the potential to overcome the current uncertainties with regard to NM dispersion properties, effective dose, and particle dissolution. In …

Sampling Effort And Uncertainty In Leaf Litterfall Mass And Nutrient Flux In Northern Hardwood Forests, Yang Yang, Ruth D. Yanai, Craig R. See, Mary A. Arthur

Forestry and Natural Resources Faculty Publications

Designs for litterfall sampling can be improved by understanding the sources of uncertainty in litterfall mass and nutrient concentration. We compared the coefficient of variation of leaf litterfall mass and nutrient concentrations (nitrogen, phosphorus, calcium, magnesium, and potassium) at different spatial scales and across years for six northern hardwood species from 23 stands in the White Mountains of New Hampshire, USA. Stands with steeper slopes (P = 0.01), higher elevations (P = 0.05), and more westerly aspect (P = 0.002) had higher interannual variation in litter mass, probably due to a litter trap design that allowed litter …

Organic Solvent Exposure And Depressive Symptoms Among Licensed Pesticide Applicators In The Agricultural Health Study, Miriam Siegel, Sarah E. Starks, Wayne T. Sanderson, Freya Kamel, Jane A. Hoppin, Fred Gerr

Epidemiology and Environmental Health Faculty Publications

Purpose

Although organic solvents are often used in agricultural operations, neurotoxic effects of solvent exposure have not been extensively studied among farmers. The current analysis examined associations between questionnaire-based metrics of organic solvent exposure and depressive symptoms among farmers.

Methods

Results from 692 male Agricultural Health Study participants were analyzed. Solvent type and exposure duration were assessed by questionnaire. An “ever-use” variable and years of use categories were constructed for exposure to gasoline, paint/lacquer thinner, petroleum distillates, and any solvent. Depressive symptoms were ascertained with the Center for Epidemiologic Studies Depression Scale (CES-D); scores were analyzed separately as continuous (0–60) …

Establishing Pine Monocultures And Mixed Pine-Hardwood Stands On Reclaimed Surface Mined Land In Eastern Kentucky: Implications For Forest Resilience In A Changing Climate, Geoffrey Bell, Kenton L. Sena, Christopher D. Barton, Michael French

Forestry and Natural Resources Faculty Publications

Surface mining and mine reclamation practices have caused significant forest loss and forest fragmentation in Appalachia. Shortleaf pine (Pinus echinata) is threatened by a variety of stresses, including diseases, pests, poor management, altered fire regimes, and climate change, and the species is the subject of a widescale restoration effort. Surface mines may present opportunity for shortleaf pine restoration; however, the survival and growth of shortleaf pine on these harsh sites has not been critically evaluated. This paper presents first-year survival and growth of native shortleaf pine planted on a reclaimed surface mine, compared to non-native loblolly pine ( …

Impacts Of A Community Supported Agriculture (Csa) Voucher Program On Food Lifestyle Behaviors: Evidence From An Employer-Sponsored Pilot Program, Jairus J. Rossi, Timothy A. Woods, James E. Allen Iv

Agricultural Economics Faculty Publications

Community supported agriculture (CSA) programs have recently received attention for their potential to influence food lifestyle behaviors and health outcomes. We build on and expand inquiries into the relationship between CSA participation and behavior change by presenting the results from a controlled pilot study of first-time CSA shareholders. We offered 95 first-time shareholders a $200 voucher to participate in a CSA. Prior to and immediately following CSA participation, these shareholders completed a survey on food lifestyle behaviors. Using econometric analyses, we measured shareholder behavior changes against an 82 person control group. All participants were drawn from a pool of individuals …

Effects Of Cultivar And Maternal Environment On Seed Quality In Vicia Sativa, Rong Li, Lijun Chen, Yanpei Wu, Rui Zhang, Carol C. Baskin, Jerry M. Baskin, Xiaowen Hu

Biology Faculty Publications

Production of high quality seeds is of fundamental importance for successful crop production. However, knowledge of the effects of increased temperature resulting from global warming on seed quality of alpine species is limited. We investigated the effect of maternal environment on seed quality of three cultivars of the leguminous forage species Vicia sativa, giving particular attention to temperature. Plants of each cultivar were grown at 1700 and 3000 m a.s.l., and mass, germination, electrical conductivity (EC) of leakage and longevity were determined for mature seeds. Seeds of all three cultivars produced at the low elevation had a significantly lower …

Reducing Equifinality Using Isotopes In A Process-Based Stream Nitrogen Model Highlights The Flux Of Algal Nitrogen From Agricultural Streams, William I. Ford, James F. Fox, Erik Pollock

Biosystems and Agricultural Engineering Faculty Publications

The fate of bioavailable nitrogen species transported through agricultural landscapes remains highly uncertain given complexities of measuring fluxes impacting the fluvial N cycle. We present and test a new numerical model named Technology for Removable Annual Nitrogen in Streams For Ecosystem Restoration (TRANSFER), which aims to reduce model uncertainty due to erroneous parameterization, i.e., equifinality, in stream nitrogen cycle assessment and quantify the significance of transient and permanent removal pathways. TRANSFER couples nitrogen elemental and stable isotope mass‐balance equations with existing hydrologic, hydraulic, sediment transport, algal biomass, and sediment organic …

Consequences Of Severe Habitat Fragmentation On Density, Genetics, And Spatial Capture-Recapture Analysis Of A Small Bear Population, Sean Mccarthy Murphy, Ben C. Augustine, Wade Allen Ulrey, Joseph Maddox Guthrie, Brian K Scheick, J. Walter Mccown, John J. Cox

Forestry and Natural Resources Faculty Publications

Loss and fragmentation of natural habitats caused by human land uses have subdivided several formerly contiguous large carnivore populations into multiple small and often isolated subpopulations, which can reduce genetic variation and lead to precipitous population declines. Substantial habitat loss and fragmentation from urban development and agriculture expansion relegated the Highlands-Glades subpopulation (HGS) of Florida, USA, black bears (Ursus americanus floridanus) to prolonged isolation; increasing human land development is projected to cause ≥ 50% loss of remaining natural habitats occupied by the HGS in coming decades. We conducted a noninvasive genetic spatial capture-recapture study to quantitatively describe the …

Effects Of Climate Warming On Net Primary Productivity In China During 1961–2010, Fengxue Gu, Yuandong Zhang, Mei Huang, Bo Tao, Rui Guo, Changrong Yan

Plant and Soil Sciences Faculty Publications

The response of ecosystems to different magnitudes of climate warming and corresponding precipitation changes during the last few decades may provide an important reference for predicting the magnitude and trajectory of net primary productivity (NPP) in the future. In this study, a process-based ecosystem model, Carbon Exchange between Vegetation, Soil and Atmosphere (CEVSA), was used to investigate the response of NPP to warming at both national and subregional scales during 1961–2010. The results suggest that a 1.3°C increase in temperature stimulated the positive changing trend in NPP at national scale during the past 50 years. Regardless of the magnitude of …

Assessing Coastal Plain Risk Indices For Subsurface Phosphorus Loss, Amy L. Shober, Anthony R. Buda, Kathryn C. Turner, Nicole M. Fiorellino, A. Scott Andres, Joshua M. Mcgrath, J. Thomas Sims

Plant and Soil Sciences Faculty Publications

Phosphorus (P) Index evaluations are critical to advancing nutrient management planning in the United States. However, most assessments until now have focused on the risks of P losses in surface runoff. In artificially drained agroecosystems of the Atlantic Coastal Plain, subsurface flow is the predominant mode of P transport, but its representation in most P Indices is often inadequate. We explored methods to evaluate the subsurface P risk routines of five P Indices from Delaware, Maryland (two), Virginia, and North Carolina using available water quality and soils datasets. Relationships between subsurface P risk scores and published dissolved P loads in …

Conservation Farming And Changing Climate: More Beneficial Than Conventional Methods For Degraded Ugandan Soils, Drake N. Mubiru, Jalia Namakula, James Lwasa, Godfrey A. Otim, Joselyn Kashagama, Milly Nakafeero, William Nanyeenya, Mark S. Coyne

Plant and Soil Sciences Faculty Publications

The extent of land affected by degradation in Uganda ranges from 20% in relatively flat and vegetation-covered areas to 90% in the eastern and southwestern highlands. Land degradation has adversely affected smallholder agro-ecosystems including direct damage and loss of critical ecosystem services such as agricultural land/soil and biodiversity. This study evaluated the extent of bare grounds in Nakasongola, one of the districts in the Cattle Corridor of Uganda and the yield responses of maize (Zea mays) and common bean (Phaseolus vulgaris L.) to different tillage methods in the district. Bare ground was determined by a supervised multi-band …

Mining Site Reclamation Planning Based On Land Suitability Analysis And Ecosystem Services Evaluation: A Case Study In Liaoning Province, China, Jiali Wang, Fuqiang Zhao, Jian Yang, Xiaoshu Li

Forestry and Natural Resources Faculty Publications

Restoration of the degraded ecosystem is a global priority for achieving sustainable development. Although increasing ecosystem service is an important goal of ecological restoration, it is rarely used to inform mine reclamation. This study proposed a reclamation strategy that incorporated land suitability analysis and ecosystem service evaluation for a mining site in Liaoning Province, China. We assessed the land suitability for three reclamation alternatives and identified suitable land uses for each location by comparing their suitability levels. For areas that were suitable for multiple land uses with the same suitability level, the future land uses cannot be identified by land …

Evaluation Of Modis Land Surface Temperature Data To Estimate Near-Surface Air Temperature In Northeast China, Yuan Z. Yang, Wen H. Cai, Jian Yang

Forestry and Natural Resources Faculty Publications

Air temperature (T_air) near the ground surface is a fundamental descriptor of terrestrial environment conditions and one of the most widely used climatic variables in global change studies. The main objective of this study was to explore the possibility of retrieving high-resolution T_air from the Moderate Resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) products, covering complex terrain in Northeast China. The All Subsets Regression (ASR) method was adopted to select the predictors and build optimal multiple linear regression models for estimating maximum (T_max), minimum (T_min), and mean (T_mean) air temperatures. …

A Compromised Liver Alters Polychlorinated Biphenyl-Mediated Toxicity, Banrida Wahlang, Jordan T. Perkins, Michael C. Petriello, Jessie B. Hoffman, Arnold J. Stromberg, Bernhard Hennig

Superfund Research Center Faculty Publications

Exposure to environmental toxicants namely polychlorinated biphenyls (PCBs) is correlated with multiple health disorders including liver and cardiovascular diseases. The liver is important for both xenobiotic and endobiotic metabolism. However, the responses of an injured liver to subsequent environmental insults has not been investigated. The current study aims to evaluate the role of a compromised liver in PCB-induced toxicity and define the implications on overall body homeostasis. Male C57Bl/6 mice were fed either an amino acid control diet (CD) or a methionine-choline deficient diet (MCD) during the 12-week study. Mice were subsequently exposed to either PCB126 (4.9 mg/kg) or the …

Impact Of Nutrition On Pollutant Toxicity: An Update With New Insights Into Epigenetic Regulation, Jessie B. Hoffman, Michael C. Petriello, Bernhard Hennig

Superfund Research Center Faculty Publications

Exposure to environmental pollutants is a global health problem and is associated with the development of many chronic diseases, including cardiovascular disease, diabetes and metabolic syndrome. There is a growing body of evidence that nutrition can both positively and negatively modulate the toxic effects of pollutant exposure. Diets high in proinflammatory fats, such as linoleic acid, can exacerbate pollutant toxicity, whereas diets rich in bioactive and anti-inflammatory food components, including omega-3 fatty acids and polyphenols, can attenuate toxicant-associated inflammation. Previously, researchers have elucidated direct mechanisms of nutritional modulation, including alteration of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling, …

An Open-Sourced Statistical Application For Identifying Complex Toxicological Interactions Of Environmental Pollutants, Jordan T. Perkins, Michael C. Petriello, Li Xu, Arnold J. Stromberg, Bernhard Hennig

Superfund Research Center Faculty Publications

The rising number of chemicals that humans are exposed to on a daily basis, as well as advances in biomonitoring and detection technologies have highlighted the diversity of individual exposure profiles (complex body burdens). To address this, the toxicological sciences have begun to shift away from examining toxic agents or stressors individually to focusing on more complex models with multiple agents or stressors present. Literature on interactions between chemicals is fairly limited in comparison with dose-response studies on individual toxicants, which is largely due to experimental and statistical challenges. Experimental designs capable of identifying these complex interactions are often avoided …

The Fate Of Carbon In Sediments Of The Xingu And Tapajós Clearwater Rivers, Eastern Amazon, Dailson J. Bertassoli Jr., André O. Sawakuchi, Henrique O. Sawakuchi, Fabiano N. Pupim, Gelvam A. Hartmann, Michael M. Mcglue, Cristiano M. Chiessi, Matthias Zabel, Enno Schefuß, Tatiana S. Pereira, Rudney A. Santos, Samantha B. Faustino, Paulo E. Oliveira, Denise C. Bicudo

Earth and Environmental Sciences Faculty Publications

The Xingu and Tapajós rivers in the eastern Amazon are the largest clearwater systems of the Amazon basin. Both rivers have “fluvial rias” (i.e., lake-like channels) in their downstream reaches as they are naturally impounded by the Amazon mainstem. Fluvial rias are widespread in the Amazon landscape and most of the sedimentary load from the major clearwater and blackwater rivers is deposited in these channels. So far, little is known about the role of Amazon rias as a trap and reactor for organic sediments. In this study, we used organic and inorganic geochemistry, magnetic susceptibility, diatom, and pollen analyses in …

Effects Of Litter On Seedling Emergence And Seed Persistence Of Three Common Species On The Loess Plateau In Northwestern China, Rui Zhang, Xiaowen Hu, Jerry M. Baskin, Carol C. Baskin, Yanrong Wang

Biology Faculty Publications

Litter accumulation resulting from land use change (enclosure) is one of the key variables influencing seedling recruitment and consequently the regeneration of plant populations and seed persistence in the soil seed bank. A better understanding of the effects of litter on seed germination and seedling emergence is crucial for developing a new set of indicators for grassland ecosystem health and for grassland management policy. We investigated the effects of seed position in litter and amount of litter covering the seed on seedling emergence and seed persistence of three common species on the Loess Plateau in northwestern China. Seed position beneath …

Ammonia And Carbon Dioxide Emissions Of Three Laying-Hen Housing Systems As Affected By Manure Accumulation Time, Timothy A. Shepherd, Hongwei Xin, John P. Stinn, Morgan D. Hayes, Yang Zhao, Hong Li

Biosystems and Agricultural Engineering Faculty Publications

Laying-hen housing design and management are the most significant factors affecting the generation and release of gaseous ammonia to the atmosphere. Transitioning the hen housing type from traditional high-rise (where manure is stored within the house for about one year) to modern manure-belt style (where manure is removed every 1 to 4 d and placed into long-term storage) has significantly improved in-barn air quality and reduced farm-level ammonia emissions. As a direct result of the advantages, 100% of new construction for U.S. egg production incorporates manure-belt systems that regularly remove manure from the houses. However, manure-belt system designs (e.g., active …