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Anuran Diversity And Abundance Across Two Sites With Varying Levels Of Light Pollution In El Valle De Antón, Coclé, Panamá, Jackson Dray Apr 2024

Anuran Diversity And Abundance Across Two Sites With Varying Levels Of Light Pollution In El Valle De Antón, Coclé, Panamá, Jackson Dray

Independent Study Project (ISP) Collection

The impact of artificial light at night (ALAN) on anuran populations has been a subject of growing concern in ecological research. Anurans are particularly susceptible to the impacts of artificial light due to their nocturnal nature and an extensive exposure throughout various stages of life histories. Exposure to artificial light has been shown to impact the larval development and reproductive behavior of anurans. The impacts on anurans juvenile populations suggest a relationship between light pollution and anuran abundance. This study aimed to investigate the hypothesis that ALAN negatively affects the abundance and diversity of anurans. Field surveys were conducted in …


Guna Community Perspectives On Attributes, Changes, And Revitalization Of Nainu Agroecological Practices In Isla Tigre, Guna Yala Comarca, Panama, Neshima Vitale-Penniman Apr 2024

Guna Community Perspectives On Attributes, Changes, And Revitalization Of Nainu Agroecological Practices In Isla Tigre, Guna Yala Comarca, Panama, Neshima Vitale-Penniman

Independent Study Project (ISP) Collection

Indigenous agroecological systems are gaining international recognition for their capacity to conserve biodiversity while promoting food security and sovereignty. Nainu is the ancestral agriculture of the Guna people of eastern Panama, and it is characterized by a successional growing system that imitates the regeneration of the tropical forest in which it is practiced. This research aimed to (a) characterize how nainu is practiced by farmers in Isla Tigre, a community in Guna Yala, (b) characterize how nainu practices have changed over time, and (c) describe how farmers and community members in Isla Tigre are envisioning and actualizing the revitalization of …


Vertebrate Diversity In The La Amistad International Park Buffer Zone, Guadalupe, Chiriqui, Panamá, Mina Olson Apr 2024

Vertebrate Diversity In The La Amistad International Park Buffer Zone, Guadalupe, Chiriqui, Panamá, Mina Olson

Independent Study Project (ISP) Collection

Forest fragmentation and increasing agricultural land use are posing threats to the diversity of vertebrates in Panama and across the Mesoamerican Biological Corridor. Protected areas are crucial for providing connectivity and maintaining vertebrate populations. For endemic species with small native ranges, these protected areas are critical for their survival due to sensitivity of habitat change. Higher species diversity and occupancy has been reported for both birds and mammals in protected and forested areas. This pilot survey of vertebrate species was conducted to determine which species live in a primary forest within the buffer zone of La Amistad International Park near …


Exploring Human Aging Proteins Based On Deep Autoencoders And K-Means Clustering, Sondos M. Hammad, Mohamed Talaat Saidahmed, Elsayed A. Sallam, Reda Elbasiony Mar 2024

Exploring Human Aging Proteins Based On Deep Autoencoders And K-Means Clustering, Sondos M. Hammad, Mohamed Talaat Saidahmed, Elsayed A. Sallam, Reda Elbasiony

Journal of Engineering Research

Aging significantly affects human health and the overall economy, yet understanding of the underlying molecular mechanisms remains limited. Among all human genes, almost three hundred and five have been linked to human aging. While certain subsets of these genes or specific aging-related genes have been extensively studied. There has been a lack of comprehensive examination encompassing the entire set of aging-related genes. Here, the main objective is to overcome understanding based on an innovative approach that combines the capabilities of deep learning. Particularly using One-Dimensional Deep AutoEncoder (1D-DAE). Followed by the K-means clustering technique as a means of unsupervised learning. …


Interactive Effects Of Co2, Temperature, And Nitrate Limitation On The Growth And Physiology Of Marine Cyanobacterium Synechococcus Sp. Ccmp 1334, Alyssa K. Sharbaugh Mar 2024

Interactive Effects Of Co2, Temperature, And Nitrate Limitation On The Growth And Physiology Of Marine Cyanobacterium Synechococcus Sp. Ccmp 1334, Alyssa K. Sharbaugh

LSU Master's Theses

The marine cyanobacterium Synechococcus sp. CCMP 1334 was grown in a continuous culture system on a 12:12 h light:dark cycle at all combinations of low and high pCO2 (400 and 1000 ppmv, respectively), nitrate availability (nitrate-limited and nutrient-replete conditions), and temperatures of 21°C, 24°C, 28°C, 32°C, and 35°C. The maximum median nutrient-replete growth rate was ~1.15 d−1 at 32 –35°C. Median growth rates at 1000 ppmv pCO2 were higher than those at 400 ppmv at all temperatures, but most of the differences were statistically insignificant. Carbon:nitrogen ratios were independent of pCO2 at a fixed relative growth rate but decreased with …


Climate Change-Associated Declines In Water Clarity Impair Feeding By Common Loons, Walter H. Piper, Max R. Glines, Kevin C. Rose Mar 2024

Climate Change-Associated Declines In Water Clarity Impair Feeding By Common Loons, Walter H. Piper, Max R. Glines, Kevin C. Rose

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Climate change has myriad impacts on ecosystems, but the mechanisms by which it affects individual species can be difficult to pinpoint. One strategy to discover such mechanisms is to identify a specific ecological factor related to survival or reproduction and determine how that factor is affected by climate. Here we used Landsat imagery to calculate water clarity for 127 lakes in northern Wisconsin from 1995 to 2021 and thus investigate the effect of clarity on the body condition of an aquatic visual predator, the common loon (Gavia immer). In addition, we examined rainfall and temperature as potential predictors …


Review On Quarrying Methods Suitable For Space Mining Missions, Daniel Chpolianski, Zong-Xian Zhang Mar 2024

Review On Quarrying Methods Suitable For Space Mining Missions, Daniel Chpolianski, Zong-Xian Zhang

Journal of Sustainable Mining

In this review paper, existing mining techniques and technologies are scrutinized for the purpose of superterrestrial use. Different aspects and challenges of a space mining mission are examined in light of the viable iron-nickel quarry operation on M-Type (metallic) asteroids. The research and findings presented in this work cover different disciplines of science and engineering, including Geology, Rock Engineering, Space Exploration, and Explosives Engineering. The particular focus of this study is on the application of shaped charge explosives in military munitions, oil well perforations, tunneling, open-pit mines, and bolder fracturing that could be deployed in asteroid mining missions. The central …


High Dietary Folic Acid Supplementation Reduced The Composition Of Fatty Acids And Amino Acids In Fortified Eggs, Ao-Chuan Yu, Yu-Han Deng, Cheng Long, Xi-Hui Sheng, Xiang-Guo Wang, Long-Fei Xiao, Xue-Ze Lv, Xiang-Ning Chen, Li Chen, Xiao-Long Qi Mar 2024

High Dietary Folic Acid Supplementation Reduced The Composition Of Fatty Acids And Amino Acids In Fortified Eggs, Ao-Chuan Yu, Yu-Han Deng, Cheng Long, Xi-Hui Sheng, Xiang-Guo Wang, Long-Fei Xiao, Xue-Ze Lv, Xiang-Ning Chen, Li Chen, Xiao-Long Qi

Faculty, Staff and Student Publications

AIMS: The study aimed to evaluate the effects of dietary folic acid (FA) on the production performance of laying hens, egg quality, and the nutritional differences between eggs fortified with FA and ordinary eggs.

METHODS: A total of 288 26-week-old Hy-Line Brown laying hens (initial body weights 1.65 ± 0.10 kg) with a similar weight and genetic background were used. A completely randomized design divided the birds into a control group and three treatment groups. Each group consisted of six replicates, with twelve chickens per replicate. Initially, all birds were fed a basal diet for 1 week. Subsequently, they were …


Thermal Ecology And Swimming Performance Of Native Tadpoles Dryophytes Femoralis In Central Florida, Jessalyn Aretz Mar 2024

Thermal Ecology And Swimming Performance Of Native Tadpoles Dryophytes Femoralis In Central Florida, Jessalyn Aretz

USF Tampa Graduate Theses and Dissertations

Urbanization and climate warming have contributed to global amphibian declines in recent decades. Amphibians are particularly vulnerable to climate and urban-induced warming because their physiological processes are dependent on temperature across all life stages, but few studies have been done on tadpole responses to warming in comparison to adult responses. The study objective was to determine how the thermal ecology and swimming performance of a native Florida tadpole varied with rearing temperature and urban level, and whether these traits are plastic or adaptive. We collected eggs from wild populations of pine woods treefrog (Dryophytes femoralis) tadpoles at an urban and …


Municipal Waste Management Based On Geomechanical Assessments Of The Landfill Site Slope – A Case Study In Southern Poland, Tomasz Janoszek, Phu Minh Vuong Nguyen, Jacek Grabowski Mar 2024

Municipal Waste Management Based On Geomechanical Assessments Of The Landfill Site Slope – A Case Study In Southern Poland, Tomasz Janoszek, Phu Minh Vuong Nguyen, Jacek Grabowski

Journal of Sustainable Mining

Over time, municipal waste landfills tend to go higher and become larger. The stability of the municipal landfill slope is one of the basic geotechnical tasks. This task ensures continuous waste deposition on the landfill surface and safety in its surroundings. With the increasing height and volume of the landfill, it is difficult to estimate the available area of the municipal landfill, where more waste can be safely deposited due to a number of variable factors, such as the geotechnical conditions of the municipal landfill, the morphological composition, age, and degree of compaction and decomposition of the deposited waste.

This …


Integrated Process Modeling, Techno-Economic Analysis And Life Cycle Assessment For Enhanced Biogas-To-Energy Sustainability And Efficiency, Rarosue Jennifer Amaraibi Mar 2024

Integrated Process Modeling, Techno-Economic Analysis And Life Cycle Assessment For Enhanced Biogas-To-Energy Sustainability And Efficiency, Rarosue Jennifer Amaraibi

USF Tampa Graduate Theses and Dissertations

This dissertation aims to enhance the cost competitiveness and minimize the environmental footprint of technologies that convert biogas to energy, contributing to global climate change mitigation efforts. Biogas, a by-product of the anaerobic decomposition of organic waste from various sources, is a renewable energy source with the potential to reduce carbon emissions and meet local energy needs. However, widespread adoption requires the development of economically viable and environmentally friendly technologies.The central hypothesis of this dissertation suggests that by adopting a holistic strategy that combines cutting-edge techniques to purify biogas and improve its conversion into valuable liquid fuels, we can substantially …


Synthesis, Molecular Characteristics, And Antibacterial Assessment Of Marine Hydroid Aqueous Extract-Based Silver Bio-Nanoparticles, Fredryk Mandey, Aulia Rhamdani Arfan, Rugaiyah Andi Arfah Mar 2024

Synthesis, Molecular Characteristics, And Antibacterial Assessment Of Marine Hydroid Aqueous Extract-Based Silver Bio-Nanoparticles, Fredryk Mandey, Aulia Rhamdani Arfan, Rugaiyah Andi Arfah

Makara Journal of Science

This investigation aims to synthesize, analyze the molecularity, and test the ability of bacterial inhibition capability of silver nanoparticles that have been synthesized by simply mixing silver nitrate and aqueous extracts of marine natural products with and without the addition of amylum as a stabilizing agent. This research, with and without the addition of amylum as a stabilizing agent, obtained 39.0 and 55.2 mg of solids of round-shaped morphology silver nanoparticles with diameters of 87.9 and 103.0 nm., respectively. In addition, the antibacterial testing assay against Staphylococcus aureus and Escherichia coli showed some considerably good results. S. aureus with the …


Hurricane Impacts On Water Resources: A Look At Nature-Based Solutions To Improve Long-Term Resilience, Fautemeh Sajadi Bami Mar 2024

Hurricane Impacts On Water Resources: A Look At Nature-Based Solutions To Improve Long-Term Resilience, Fautemeh Sajadi Bami

USF Tampa Graduate Theses and Dissertations

Severe storms are a common occurrence in the state of Florida. Hurricane events may cause hazards such as flooding, property damage, death, and many others. Such far-reaching impacts may potentially result in dangerous consequences where they occur. Of interest to this study were the impacts on water resources and water quality caused by storms. Hurricanes can bring about a deluge. An apparent excess of water may cause the notion of water scarcity to seem less significant. However, problems with potable water can be quite frequent due to storms.

This research sought to address the impacts of severe storms on water …


The Impacts Of Nature-Based Sediment Restoration Practices On Coastal Wetland Soil Biogeochemistry, Jacob Z. Cheng Mar 2024

The Impacts Of Nature-Based Sediment Restoration Practices On Coastal Wetland Soil Biogeochemistry, Jacob Z. Cheng

LSU Master's Theses

Coastal marshes provide many valuable ecosystem services. However, these wetlands are threatened worldwide, being subject to sea level rise, sediment starvation, subsidence, coastal edge erosion, etc. Many efforts are being made to counteract this wetland loss and preserve the ecosystem services. Two such methods are sediment diversion and the thin layer placement (TLP) of dredged sediment.

Sediment diversion involves reconnecting the main channel of a river body to disconnected wetlands, supplying much needed soil-building materials. However, this method affects the salinity of the waters, introducing large amounts of freshwater into the system. Salinity changes can affect marsh biogeochemistry. Most ecological …


Law Governing Variations In Water-Pressure Transmission Rate In Confined Aquifers, Wang Wenxue, Wang Bosen, Gao Yanwei, Wu Bing, Nie Tianyu Mar 2024

Law Governing Variations In Water-Pressure Transmission Rate In Confined Aquifers, Wang Wenxue, Wang Bosen, Gao Yanwei, Wu Bing, Nie Tianyu

Coal Geology & Exploration

The water pressure in aquifers is transmitted as energy, with a transmission rate much higher than the migration rate of water particles. The water-pressure transmission rate holds great significance for the safe construction and disaster forecast and prediction of underground engineering under high-pressure water aquifers and bodies. Focusing on the confined aquifers bearing no cohesive soil, this study explored the law governing the changes in the water-pressure transmission rate through theoretical analysis, numerical simulations, field experiments, and laboratory physical model tests. Key findings are as follows: (1) The transmission of water-pressure changes in the aquifers exhibited noticeable hysteresis. The transmission …


Preserving Linguistic Diversity In The Digital Age: A Scalable Model For Cultural Heritage Continuity, James Hutson, Pace Ellsworth, Matt Ellsworth Mar 2024

Preserving Linguistic Diversity In The Digital Age: A Scalable Model For Cultural Heritage Continuity, James Hutson, Pace Ellsworth, Matt Ellsworth

Faculty Scholarship

In the face of the rapid erosion of both tangible and intangible cultural heritage globally, the urgency for effective, wide-ranging preservation methods has never been greater. Traditional approaches in cultural preservation often focus narrowly on specific niches, overlooking the broader cultural tapestry, particularly the preservation of everyday cultural elements. This article addresses this critical gap by advocating for a comprehensive, scalable model for cultural preservation that leverages machine learning and big data analytics. This model aims to document and archive a diverse range of cultural artifacts, encompassing both extraordinary and mundane aspects of heritage. A central issue highlighted in the …


Improving Medical Image Classification Accuracy Through Unsupervised Segmentation And Confounder Mitigation With Limited Data, Nikolai Fetisov Mar 2024

Improving Medical Image Classification Accuracy Through Unsupervised Segmentation And Confounder Mitigation With Limited Data, Nikolai Fetisov

USF Tampa Graduate Theses and Dissertations

Medical images are indispensable for assisting health care professionals to make more accurate cancer diagnosis and prognosis decisions. Several image modalities exist including, but not limited to, histopathology or whole slide images (WSI), computed tomography (CT), positron emission tomography (PET) and radiography (i.e., X-Ray), each having their own application in clinical practice.

Today, machine learning and deep learning methods have evolved to the point of being practically usable. These approaches learn and extract knowledge from data to make possible automating certain tasks. At the point of writing this dissertation, they have reached human-level performance in general image recognition tasks, became …


03.25.2024 Orsp Connect, Liz Williamson Mar 2024

03.25.2024 Orsp Connect, Liz Williamson

ORED Newsletter

Cammi Thornton, Compliance Training Requirements


In Silico Analysis Of C-Type Lectins As Co-Infection Receptors Of Dengue And Chikungunya Viruses In Aedes Aegypti, Munawir Sazali, R. C. Hidayat Soesilohadi, Nastiti Wijayanti, Tri Wibawa, Arif Nur Muhammad Ansori Mar 2024

In Silico Analysis Of C-Type Lectins As Co-Infection Receptors Of Dengue And Chikungunya Viruses In Aedes Aegypti, Munawir Sazali, R. C. Hidayat Soesilohadi, Nastiti Wijayanti, Tri Wibawa, Arif Nur Muhammad Ansori

Makara Journal of Science

Aedes aegypti is a primer vector of dengue virus (DENV) and chikungunya virus (CHIKV). The susceptibility of mosquitoes to DENV and CHIKV depends on their recognition receptor of pathogens. C-type lectins (CTLs) are an important mediator of virus infection in A. aegypti. This study aims to identify potential receptors and determine the binding affinity between ligand–receptor interaction, CTLs and virus envelopes (DENV-1, 2, 3, and 4 and CHIKV) interaction based on in silico analysis. Sample sequences were obtained from GenBank (NCBI), and 10 CTLs were acquired from VectorBase. Homology modeling based on a minimum standard of 20% was processed …


Silvopastoral Agroforestry In Upland And Lowland Uk Grassland: Tree Growth And Animal Performance, W R. Eason, R Lavender, R O. Clements, C Duller, E Gill, M Hislop Mar 2024

Silvopastoral Agroforestry In Upland And Lowland Uk Grassland: Tree Growth And Animal Performance, W R. Eason, R Lavender, R O. Clements, C Duller, E Gill, M Hislop

IGC Proceedings (1977-2023)

Trees, individually protected from herbivore damage using plastic shelters, were planted at two densities (100 and 400 stems/ha) into sheepgrazed pasture in upland and lowland UK grassland sites in 1988. Tree and animal performance were compared with conventional forestry (no sheep) and pasture (no tree) systems. Effects on tree growth and survival are highly species and site dependent although some treatment effects did emerge. Tree shelters encouraged rapid early height growth compared to forestry controls although in some cases tree form was also adversely affected. Generally tree performance within agroforestry treatments was better at the higher planting density. Eight years …


Use Of Annual Self-Reseeding Legumes In An Oak Forest In Central Italy, P Talamucci, G Argenti, A Pardini, S Piemontese, N Stagliano Mar 2024

Use Of Annual Self-Reseeding Legumes In An Oak Forest In Central Italy, P Talamucci, G Argenti, A Pardini, S Piemontese, N Stagliano

IGC Proceedings (1977-2023)

A trial has been carried out for three years in an oak coppice geometrically thinned out of Mediterranean Central Italy, about the functioning of a pastoral system made by four different resources: native pasture, subterranean clover (Trifolium brachycalycinum Katzn. et Morley) in pure stand, strips thinned out and firebreaks improved with oversown subclover, all grazed by sheep. Subclover increased the forage yield and improved the palatabilty of the pasture and the regularity of grazing; the higher biomass intake by animals reduced the quantity of dried biomass in summer and contributed to keep low either fire hazards or flame diffusion …


The Effects Of Shelterbelts On Adjacent Pastures And Soils In A Temperate Climate, A G. Gillingham, M F. Hawke Mar 2024

The Effects Of Shelterbelts On Adjacent Pastures And Soils In A Temperate Climate, A G. Gillingham, M F. Hawke

IGC Proceedings (1977-2023)

Two trials were conducted to differentiate the direct (exposure) from the indirect (modified soil fertility due to nutrient transfer by grazing animals) effects of farm shelterbelts on associated pasture growth.Soil from close to “unmanaged”shelterbelts with dense shelter to ground level had relatively high potassium (K) levels and, in a glasshouse situation, provided more pasture growth than soil from further distances, or from adjacent to “managed” shelterbelts. Pasture grown in boxes of a common soil implanted at increasing distances from a shelterbelt also produced highest growth rates close to shelter. These results generally explain the pattern of resident pasture growth, except …


Temperate Pasture And Sheep Performance Under Radiata Pine And In Open Pasture, K M. Pollock, R J. Lucas, D B. Pownall, S E. Thomson Mar 2024

Temperate Pasture And Sheep Performance Under Radiata Pine And In Open Pasture, K M. Pollock, R J. Lucas, D B. Pownall, S E. Thomson

IGC Proceedings (1977-2023)

Forage production from years 4 to 6 of an agroforestry system at 400-600 trees per ha and pasture alone were compared for a temperate sub-humid environment. Forage production was best for lucerne pasture followed by phalaris/clover and cocksfoot/clover, and least for ryegrass/clover and the ryegrass only pastures. Total pasture production in the agroforest relative to the open pasture was from 10% more for phalaris to 20% less for lucerne. Sheep carrying capacity over all pastures was 14.6 sheep/ha in the open and 11.8 sheep/ha in the agroforest and varied by ±15% according to the pasture types.


Grazing Management Of Tagasaste (Chamaecytisus Proliferus) For Sheep And Cattle Production In Southern Australia, N J. Edwards, G M. Allen, D M. Mcneill, C M. Oldham Mar 2024

Grazing Management Of Tagasaste (Chamaecytisus Proliferus) For Sheep And Cattle Production In Southern Australia, N J. Edwards, G M. Allen, D M. Mcneill, C M. Oldham

IGC Proceedings (1977-2023)

Direct grazing of hedgerows of tagasaste (Chamaecytisus proliferus) by sheep or cattle appear to be very robust systems. Tagasaste persists under a continuous grazing regime with cattle such that plant regrowth maintained between 5 and 10 cm in length produces in excess of 215 kg of animal liveweight/ha/year. This level of production is also sustained within a rotational grazing regime. Under both grazing systems cattle production within a year is highly seasonal, with liveweight gains from young cattle peaking at 1.0-1.5 kg/head/day in winter and spring, but dropping to maintenance only by late summer-autumn. Sheep, like cattle, can …


Shrub Palatability To Rusa Deer (Cervus Timorensis Russa) In New Caledonia, C Corniaux, S Le Bel, J M. Sarrailh Mar 2024

Shrub Palatability To Rusa Deer (Cervus Timorensis Russa) In New Caledonia, C Corniaux, S Le Bel, J M. Sarrailh

IGC Proceedings (1977-2023)

The objective of this study was to determine a palatability scale of five shrub legumes to rusa deer during the dry season in New Caledonia. Acacia ampliceps and Samanea saman remain low in acceptability. Gliricidia sepium is more palatable but quite less than Leucaena leucocephala (native cultivar) and Calliandra calothyrsus (San Ramon). Therefore, since the regression of Leucaena leucocephala population, Calliandra calothyrsus could be very promising to replace it in the deer diet. On the other hand, Acacia ampliceps seems to be the most interesting shrub legume to plant in the west coast, where soil erosion, due to successive droughts …


Soil Nutrient Redistribution Pattern About The Tree In A Silvopastoral System, L C. Nwaigbo, H G. Miller, A R. Sibbald, G Hudson Mar 2024

Soil Nutrient Redistribution Pattern About The Tree In A Silvopastoral System, L C. Nwaigbo, H G. Miller, A R. Sibbald, G Hudson

IGC Proceedings (1977-2023)

The objective of this paper is to report the effect of animal-tree interactions on soil nutrient redistribution pattern in a grazed silvopastoral experiment site at Glensaugh, in NE Scotland. Scots pine (Pinus sylvestris L) tree species were planted in square lattice arrangements at 5 m x 5 m, spacing (400 stems/ha) on plots replicated over three blocks in Randomized Complete Block design on a predominantly rye grass (Lolium perenne L) pasture which was grazed by sheep yearly from April to October. Included in the design were grazed pasture plots without trees (Control). Soil samples were collected from around …


Trees For Shelter: The Implications In Agroforestry System, L C. Nwaigbo, A R. Sibbald, G Hudson Mar 2024

Trees For Shelter: The Implications In Agroforestry System, L C. Nwaigbo, A R. Sibbald, G Hudson

IGC Proceedings (1977-2023)

The objective of this study was to determine the horizontal and vertical variations in soil penetration resistance (PR) observed at tree-scale in silvopastoral plots that were grazed by sheep with and without trees. Sycamore trees (Acer pseudoplatanus L) were planted in the spring of 1988 at 10 m x 10 m spacing (100 stems/ha) at Glensaugh NE of Scotland on plots replicated over three blocks in Randomized Complete Block design on a predominantly rye grass (Lolium perenne L) pasture. Included in the design were pasture plots without trees (Control). The experiment is grazed by sheep yearly from April to …


A Silvopastoral System In The North Atlantic Zone Of Costa Rica: Combining Indigenous Timber Species With Dairy Pasture Swards, A Moulaert- Quiros, J P. Mueller, M Villarreal, R Piedra, L Villalobos Mar 2024

A Silvopastoral System In The North Atlantic Zone Of Costa Rica: Combining Indigenous Timber Species With Dairy Pasture Swards, A Moulaert- Quiros, J P. Mueller, M Villarreal, R Piedra, L Villalobos

IGC Proceedings (1977-2023)

The objective of this study was to design, establish and monitor a silvo pastoral experiment on a dairy farm in the northern Atlantic region of Costa Rica. Indigenous timber species, Vochysia guatemalensis and Hyeronima alchorneoides were used together with or without the tropical pasture legume, Arachis pintoi in a split plot design with a 4 x 2 x 2 factorial arrangement. First year establishment was good for the tree component (2.3 to 10 % mortality) but poor for A. pintoi (4 to 5 % of sward). Poor legume establishment was attributed to lax grazing management and excess competition from existing …


Productivity Of Three Tree Legumes Grazed By Cattle, R C. Gutterridge Mar 2024

Productivity Of Three Tree Legumes Grazed By Cattle, R C. Gutterridge

IGC Proceedings (1977-2023)

Three tree legumes Albizia chinensis, Leucaena leucocephala K 636 and Tipuana tipu were grown in conjunction with the grass Brachiaria decumbens and grazed by weaner cattle at a stocking rate of 2.5 animals per hectare for a total of 447 days. Albizia was best adapted to this acidic, poorly drained site in south east Queensland giving the highest yields of edible dry matter, high survival rate and moderate liveweight gains of 0.45 kg/head/day. The productivity of L. leucocephala K 636 was always poor but it gave the highest liveweight gains of all treatments in the first 280 days of grazing, …


Morphological And Physiological Response Of Planeleaf Willow (Salix Planifolia Pursh.) To Simulated Browsing, L Xu, J L. Dodd, M A. Smith, Q D. Skinner, W A. Laycock Mar 2024

Morphological And Physiological Response Of Planeleaf Willow (Salix Planifolia Pursh.) To Simulated Browsing, L Xu, J L. Dodd, M A. Smith, Q D. Skinner, W A. Laycock

IGC Proceedings (1977-2023)

Morphological and physiological responses of planeleaf willow (Salix planefolia Pursh.) to simulated browsing were studied under controlled conditions. The treatments consisted of every combination of three clipping intensities (30%, 60% and 90% of current twigs length removal) and three clipping timings (late winter, early spring and mid-summer). Increased clipping intensity stimulated bud activation; increased total leaf area and leaf size and increased the length of current year’s twigs. Mid-summer browsing increased the total number of leaves, the number of current twigs and decreased the length of current twigs. Higher browsing intensity resulted in higher photosynthetic rate of recently matured …