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Biochar: Properties And Potential Benefits For Agricultural Soil In Rwanda, Andromede Uwase

Honors Program: Senior Projects (Public)

Physical and chemical soil degradation is becoming a major challenge for agricultural productivity in Rwanda, which is the most important part of the country’s economy. The wide spreading soil degradation in Rwanda is mainly a result of naturally poor soils coupled with unsustainable soil management leading to, for example, accelerated soil erosion, acidification, nutrient loss, compaction, and to decreasing yields. Biochar, as an end product of pyrolysis of biomass in the absence of oxygen, has been proposed as a soil amendment in remediation strategies because of its positive effects on soil productivity relevant parameters such as soil pH, structure, nutrient …

Estimating Groundnut Yield In Smallholder Agriculture Systems Using Planetscope Data, Daniel Kpienbaareh, Kamaldeen Mohammed, Isaac Luginaah, Jinfei Wang, Rachel Bezner Kerr, Esther Lupafya, Laifolo Dakishoni

Faculty Publications - Geography, Geology, and the Environment

Crop yield is related to household food security and community resilience, especially in smallholder agricultural systems. As such, it is crucial to accurately estimate within-season yield in order to provide critical information for farm management and decision making. Therefore, the primary objective of this paper is to assess the most appropriate method, indices, and growth stage for predicting the groundnut yield in smallholder agricultural systems in northern Malawi. We have estimated the yield of groundnut in two smallholder farms using the observed yield and vegetation indices (VIs), which were derived from multitemporal PlanetScope satellite data. Simple linear, multiple linear (MLR), …

Contributions Of Agroforestry Systems To Food Provisioning Of Peasant Households: Conflicts And Synergies In Chiapas, Mexico, Lorena Soto-Pinto, Sandra Escobar Colmenares, Marina Benítez Kanter, Angelita López Cruz, Erin Estrada Lugo, Balente Herrera Hernández, Estelí Jiménez-Soto

School of Geosciences Faculty and Staff Publications

Traditional agroforestry systems are widely recognized for their contributions to provisioning, support, regulation, and cultural services. However, because of the advancement of industrial agriculture and a corporative food system, peasants' food systems are rapidly undergoing transformation. We identify the contributions of four types of agroforestry systems (AFS)—shade cocoa agroforest, shade coffee agroforest, milpas and homegardens—to food provisioning in peasant families and discuss conflicts between traditional food systems and the contemporary industrial model of production and consumption confronted by peasants and semi-proletarian migrants. We carried out research in 17 peasant communities in Chiapas, Mexico, and conducted 97 semi-structured interviews and agroecological …

Influence Of Abiotic Drivers On 1-Year Seedling Survival Of Six Mangrove Species In Southeast Asia, Taylor M. Sloey, Kiah Eng Lim, Jared Moore, Jie Min Heng, Jia Min Heng, Michiel Van Breugel

Biological Sciences Faculty Publications

Establishment and survival of plant species in systems with dominant environmental drivers (i.e. factors that exert disproportionate control over species establishment and survival) is often thought to be dominated by one master variable. In forested wetlands such as mangroves, hydrology is typically considered the dominant limiting driver. At the same time, light is a major driver of plant community dynamics, with some of the best understood plant life-history tradeoffs related to fast growth under high-light conditions versus survival under low-light conditions. Yet light is given relatively limited consideration in mangrove research compared to other drivers. Understanding the relative importance of …

Performance Of Black Soldier Fly Frass Fertiliser On Maize (Zea Mays L.) Growth, Yield, Nutritional Quality, And Economic Returns, C. M. Tanga, D. Beesigamukama, M. Kassie, P. J. Egonyu, Changeh J. Ghemoh, Kiatoko Nkoba, S. Subramanian, A. O. Anyega, S. Ekesi

All Peer-Reviewed Publications

Although the black soldier fly frass fertiliser (BSFFF) is globally recognised as a promising and potential high-quality organic fertiliser, there is inadequate information on its impact on the growth performance and nutritional status of maize. Furthermore, no information exist on their combination with mineral fertiliser (NPK) as well as economic impact on maize production. This study evaluated the comparative impact of BSFFF, NPK and commercial organic fertiliser (Evergrow®) on growth, nitrogen use efficiency, yield, nutritional quality, and profitability of maize under greenhouse conditions. The treatments included: (1) sole application of BSFFF, conventional compost of brewers’ spent grain (BSG), Evergrow, and …

Minimum Dataset And Metadata Guidelines For Soil-Test Correlation And Calibration Research, Nathan A. Slaton, Sarah E. Lyons, Deanna L. Osmond, Sylvie M. Brouder, Steve W. Culman, Gerson L. Drescher, Luciano C. Gatiboni, John Hoben, Peter J.A. Kleinman, Joshua M. Mcgrath, Robert O. Miller, Austin Pearce, Amy L. Shober, John T. Spargo, Jeff J. Volenec

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Soil-test correlation and calibration data are essential to modern agriculture, and their continued relevance is underscored by the expansion of precision farming and the persistence of sustainable soil management priorities. In support of transparent, science-based fertilizer recommendations, we seek to establish a core set of required and recommended information for soil-test P and K correlation and calibration studies, a minimum dataset, building on previous research. The Fertilizer Recommendation Support Tool (FRST) project team and collaborators are developing a national database that will support a soil-test-based nutrient management decision aid tool. The FRST team includes over 80 scientists from 37 land-grant …

Biofilm Harvesters In Coastal Settings Of The Early Palaeozoic, Nora Noffke, M. Gabriela Mángano, Luis A. Buatois

OES Faculty Publications

The ichnogenera Syringomorpha and Daedalus are here interpreted as products of infaunal biofilm harvesters. This study investigated: (1) Syringomorpha nilssoni and Syringomorpha isp. from the Cambrian Series 2‐Miaolingian Campanario Formation, northwest Argentina; and (2) Daedalus halli from the Floian Grès et Schistes de la Cluse de l’Orb Formation, Montagne Noire, France. Syringomorpha nilssoni occurs in sandy to mixed intertidal to lower shoreface deposits, whereas Syringomorpha isp. in the lower intertidal zone. Daedalus halli occurs in a lagoon and intertidal to lower shoreface sands of a barrier island. Syringomorpha and Daedalus comprise a vertical J‐shaped causative burrow and deep spreite. These …

The Times, They Are A-Changin': Tracking Shifts In Mental Health Signals From Early Phase To Later Phase Of The Covid-19 Pandemic In Australia, Siqin Wang, Xiao Huang, Tao Hu, Mengxi Zhang, Zhenlong Li, Huan Ning, Jonathan Corcoran, Asaduzzaman Khan, Yan Liu, Jiajia Zhang, Xiaoming Li

Geosciences Faculty Publications and Presentations

Introduction Widespread problems of psychological distress have been observed in many countries following the outbreak of COVID-19, including Australia. What is lacking from current scholarship is a national-scale assessment that tracks the shifts in mental health during the pandemic timeline and across geographic contexts.

Methods Drawing on 244 406 geotagged tweets in Australia from 1 January 2020 to 31 May 2021, we employed machine learning and spatial mapping techniques to classify, measure and map changes in the Australian public’s mental health signals, and track their change across the different phases of the pandemic in eight Australian capital cities.

Results Australians’ …

The Influence Of Rising Atmospheric Co2 On Grassland Ecosystems, J. A. Morgan, P. C. D. Newton, J. Nösberger, C. E. Owensby

IGC Proceedings (1977-2023)

Increasing atmospheric CO₂ concentrations and climatic change will have significant effects on the ecology of grasslands. This paper evaluates results from four CO₂ enrichment studies in contrasting grasslands. A Swiss study investigates the effects of elevated CO₂ (600 μL L^-1 CO₂) on perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L), a New Zealand study examines how elevated CO₂ (475 μL L^-1 CO₂) affects a botanically diverse pasture, and studies in the Kansas tallgrass prairie and the Colorado shortgrass steppe investigate the effects of an approximate …

Water-Use Efficiency And Infiltration Under Different Rangeland Conditions And Cultivation In A Semi-Arid Climate Of South Africa, Hennie A. Snyman

IGC Proceedings (1977-2023)

The objective of this study was to determine the impact of rangeland in different botanical composition classes (good, moderate and poor), on water-use efficiency (WUE: crude protein produced per unit of evapotranspiration) and soilwater content. The same measurements were also made on an undisturbed bare soil surface and soil cultivated twice per annum. Evapotranspiration was determined by quantifying the soil-water balance equation with the aid of runoff plots and soil-water content measurements done by a neutron hydroprobe. Water-use efficiency declined significantly (P ≤ 0.01) with rangeland degradation. Rangeland in good condition averaged a WUE of 0.28 kg crude protein ha …

Ecophysiology And Management Response Of The Subtropical Grasslands Of Southern South America, E. J. Berretta

IGC Proceedings (1977-2023)

The subtropical grasslands of Southern South America (campos) are located approximately in the range of 24° S to 37° S latitude. These grasslands are dominated by C₃ and C₄ grasses, and in a lesser extent to herbaceous plants, shrubs and dispersed trees, with some exceptions in particular regions. Previous to the introduction of large herbivores, at the beginning of the XVII century, like cattle and horses, shrubs and tall grasses dominated the vegetation. Then, associated with greater grazing pressure and partially due to fire, the original campos are maintained, actually in a pseudo-climax herbaceous phase. These native communities …

Characterization Of Forage Selected By Cattle On Communal Range In Manhiça, Mozambique, O. Faftine, A. Alage, J. P. Muir

IGC Proceedings (1977-2023)

Forage selection by 10 cattle herds was observed monthly over 2 years on a communal rangeland. Plants grazed were hand-plucked as representative of both species and plant portions being cropped by cattle. Herds were led to green pasture year-round. Nutrient concentration of species and plant portions selected by cattle indicated adequate crude protein and calcium but phosphorus deficiency during the dry season. Well-drained escarpments and uplands were more important during the rains while upland depressions and the Nkomati valley were essential for adequate forage intake during the dry seasons.

The Influence Of Large Animal Diversity In Grazed Ecosystems, M. G. Murray, D. R. Baird

IGC Proceedings (1977-2023)

Field observations in the Serengeti National Park, Tanzania have revealed several modes of grazing system, including migration, sustained-yield grazing and grazing succession which contribute on the one hand to ecological separation of herbivores by habitat choice, but on the other hand to positive association of species on wet season pastures known as hot spots. Drawing from results of experimental field studies, we consider what is known about resource competition and facilitation, the two key ecological processes underlying these grazing systems, and specify the shape of the relationship between species richness and pasture height that is predicted depending on which process …

Grassland Use And Plant Diversity In Grazed Ecosystems, V. A. Deregibus, E. J. Jacobo, O. E. Ansin

IGC Proceedings (1977-2023)

Earth biomes are being deconstructed, through unprecedented rates of species disappearance or invasion (McCann 2000). This, added to the threat of global environmental change and changes in values of a developed society, caused that biodiversity became a topic that has captured the attention of the public as well as the scientific community. Such concern on the importance of biodiversity is based in four basic reasons clearly described by West (1993): (i) morality, that aims for the protection of species; (ii) aesthetics, as people desire to see and appreciate the living parts of nature; (iii) economics and, (iv) the array …

The Effect Of Phosphorus Fertilization On Botanical Composition And Production In Temperate Pastures In Argentina, E. J. Jacobo, A. M. Rodríguez, M. F. Garbulsky, P. Scardoni, V. A. Deregibus

IGC Proceedings (1977-2023)

The objective of this paper is to evaluate floristic changes and above-ground primary production in native grasslands and old pastures dominated by tall fescue (Festuca arundinacea) that were fertilized with different levels of phosphorus. For this, aerial biomass was sequentially harvested from November 1998 to October 1999. Above-ground production of native grassland more than doubled (from 3000 to 7300 kg DM/ha) with the highest level of P through the increment of three naturalized species: the winter annual ryegrass (Lolium multiflorum) and two legumes: white clover (Trifolium repens) and lotus (Lotus corniculatus). In …

Core Collection Approaches And Genetic Diversity In Flemingia Macrophylla, R. Schultze‐Kraft, M. Peters

IGC Proceedings (1977-2023)

Core collections are a useful means to optimise the management, including conservation, of forage germplasm collections. Such optimisation is warranted in view of increasingly limited research resources. As there are several potential options to create core collections, a project is presented in which three approaches are compared: (i) based on germplasm origin information; (ii) genetic diversity assessment by agronomic characterisation/evaluation; and (iii) DNA markers. As example-species for the project, the tropical legume shrub Flemingia macrophylla is selected because of its particular multiple-use potential in smallholder production systems. An important diversity descriptor is the content of tannins influencing feed and litter …

Analysis Of Some Farm Driving Variables And Its Relation With Milk Production In A Pastoral Dairy Farm Of Buenos Aires, Argentina, J. L. Rossi, A. Ayala Torales, G. Acosta, V. A. Deregibus

IGC Proceedings (1977-2023)

The quantity of milk solids produced determines a dairy farm income and contributes to its profit. Total pasture production, forage quality and herd consumption are factors to be managed in this production system. The outcomes of two years were analyzed. Primary production showed its dependence on climatic conditions and use of technological inputs. Forage quality was promoted through interseeding legumes, applying fertilizer and maintaining the pasture young and leafy. Total forage removed by the herd was similar in both years although pasture production decreased. It was possible to cope with seasonal variations in forage production, by varying the grazing pressure …

Stubble Height Effects On Limpograss Pasture Characteristics And Performance Of Beef Heifers, Y. C. Newman, Lynn E. Sollenberger, W. E. Kunkle, D. B. Bates, C. G. Chambliss, A. M. Fox

IGC Proceedings (1977-2023)

Limpograss (Hemarthria altissima [Poir.] Stapf. & C.E. Hubb.) is a C₄ species used in Florida beef production systems because of its cool-season growth, persistence on poorly drained soils, and high yield and digestibility. Animal performance on limpograss pastures, however, has been limited by low herbage crude protein (CP). This study evaluated the effect of canopy height of limpograss pastures and N supplementation of grazing cattle on sward characteristics and weight gain and blood urea N (BUN) concentration of yearling beef heifers. Under continuous stocking, six treatments were imposed that included all combinations of three stubble heights (20, 40, …

The Duration Of Regrowth Period And The Structural Traits In A Rotationally Grazed Panicum Maximum Sward, Carlos A. M. Gomide, J. A. Gomide

IGC Proceedings (1977-2023)

Panicum maximum 'cv'. Mombaça was rotationally grazed by steers. Three regrowth periods based on the number of expanded leaves per tiller: 2.5; 3.5 and 4.5, were compared. Three groups of seven tester steers, one for each treatment, grazed the replications of each experimental paddocks, the animals being removed from a paddock after 4 to 5 day grazing period when its sward leaf area index (LAI) was 1.5, on the average. Sward height and available biomass increased while tiller population density and leaf-stem ratio decreased with regrowth period. Overall averages observed for LAI and photosyntheticly active radiation interception by the end …

Dairy Cow Performance On Pasture-Based Feeding Systems And In Confinement, Renato S. Fontaneli, Lynn E. Sollenberger, C. R. Staples

IGC Proceedings (1977-2023)

Interest in grazing systems is growing among farmers in the USA as a means of reducing feed costs for lactating dairy cows. An experiment was conducted near Gainesville, FL to compare milk production and composition and milk income minus feed costs from two pasture-based systems with those of a conventional confinement housing system over a 276-d period. System 1 was based on a mixture of rye (Secale cereale L.), annual ryegrass (Lolium multiflorum Lam.), crimson clover (Trifolium incarnatum L.), and red clover (Trifolium pratense L.) during the winter-spring seasons and pearl millet (Pennisetum glaucum [L.] …

2021 Grand River Water Quality, Allison Romanski, Madeleine Lang

Student Summer Scholars Manuscripts

2021 Grand River Water Quality Sampling

The goals of this research project were to collect repeat samples at designated reaches and under different flow conditions along the Grand River, sample the entire Grand River over a short period of time, collaborate with wastewater treatment plant labs and technicians to analyze water samples, and to calculate a Water Quality Index (WQI) for samples collected.

Seven different reaches were sampled and over 120 samples were collected between May 7th and August 12th of 2021. Water samples were collected and analyzed for nitrate, total phosphate, ammonium, chloride, dissolved oxygen, biological oxygen demand , …

Influence Of Grassland Management And Grazing By Different Farm Animals On Animal Performance And Flora Alterations, W. Jentsch, H.-D. Matthes, A. Admasu, H. Möhring

IGC Proceedings (1977-2023)

The objectives of this study were to test the possibilities of using different farm animals for landscape care on extensive pasture, taking into account their particular performance, and to analyse alterations of the flora in consequence of grazing by different animals and various pasture management. Salers had the highest (836g/d) and Galloways (584g/d) the lowest live weight gain as compared with the other breeds (771g/d). Lambs had higher live weight when grazing together with cattle and horses (mixed grazing) than under one species grazing. The number of legume increased and that of grass decreased. Following 3 years the grazing animals …

Orchardgrass Pastures For Early-Weaned Beef Calves, J. C. Waller, H. A. Fribourg, C. Dixon, A. E. Fisher, B. V. Conger

IGC Proceedings (1977-2023)

Orchardgrass (Dactylis glomerata) grown alone or with ladino white (Trifolium repens) and red (T. pratense) clovers, provides a high quality March to June pasture. However, many beef producers have their cows calving in January-March, thus producing offspring that are too young to utilize spring forage well. As an alternative, some producers have their cows bred so that calves are born in autumn (September-November). By spring, these calves are old enough to consume pasture forage. The few earlier studies on early weaning of fall-born calves consist of drylot feeding of high quality hay or concentrates. …

Management Of Meadow Fescue Pasture For High-Producing Dairy Cows In Northern Japan, K. Sudo, K. Ochiai, T. Ikeda

IGC Proceedings (1977-2023)

The objective of this study was to establish an intensive grazing system of meadow fescue (Festuca elatior L.) pasture for high-producing dairy cows in some areas of Japan where soil freezes in winter. Plant succession of meadow fescue pastures that had been grazed at different plant heights and milk production from cows grazed on meadow fescue pasture compared to that from cows grazed on perennial ryegrass pasture were surveyed over a five year period. Succession of meadow fescue pasture depended on the management of plant height before grazing use. Milk production from cows grazed on meadow fescue pasture was …

Leaf Blade Selection By Sheep In Kleingrass (Panicum Coloratum L.) Pastures With Different Deferment Periods, P. Sierra, M. S. Cid, M. A. Brizuela, C. M. Ferri

IGC Proceedings (1977-2023)

The winter use of standing dead biomass produced by warm season grasses during the previous growing season may be an alternative to grazing systems in the semi-arid Pampean Region of Argentina. This study evaluated: 1) the effect of different deferment periods on the leaf blade percentage and quality of ‘kleingrass’ (Panicum coloratum L.), a warm season specie recently introduced to that region, and 2) whether rams grazing the vegetation accumulated during these different periods are able to select leaf blades to maintain the quality of their diets. It was generated three treatments by deferment of the forage produced after …

Microhistological Estimation Of Leaf Blade Percentage In Diets From Monoespecific Pastures, P. Sierra, M. S. Cid, M. A. Brizuela, C. M. Ferri

IGC Proceedings (1977-2023)

Although a decrease in the leaf-stem ratio affects the nutritive value of pastures, herbivores can reinforce selection for leaf blades to maintain the quality of their diets. This study evaluated whether the percentage of fragments with furrows in blades could be used to estimate the relative intake of this part of the leaves by herbivores grazing monoespecific pastures. It was worked with vegetation of kleingrass (Panicum coloratum L.) from paddocks with three deferment periods. Blade samples, and different plant part mixtures hand compounded were in vitro digested. The digestion residues were microhistological analyzed determining the number of fragment with …

Late Winter Dietary Overlap Among Greater Rheas And Domestic Herbivores On The Argentinean Flooding Pampa, G. Vacarezza, M. S. Cid, F. Milano

IGC Proceedings (1977-2023)

This study evaluates the dietary overlap among greater rheas (Rhea americana L.) sheep and cattle in the Flooding Pampa, Buenos Aires, Argentina during late winter, when is observed the lowest forage availability. The work was carried out with the following forage classes (FC): warm and cool season grasses and forbs (legumes and no-legumes). Diet botanical composition was estimated by microanalysis of faeces. Principal Component Analysis and Kulcyznsky´s index of similarity were used for data analysis. Rhea populations selected diets with higher forb percentages. On the contrary, vegetation structure and their own morpho-physiology conditioned cattle to diets almost exclusively gramineous. …

Beef Calf Production Using Year-Round Grazing On Tropical Grass Pasture In Summer Combined With Cool Temperate Grass Pasture In Winter, Y. Nakanishi, K. Shindou, S. Watanabe, K. Yamamoto, K. Hagino

IGC Proceedings (1977-2023)

Bahiagrass (Paspalum notatum Fluegge) showed a poor quality with low crude protein in summer but blood biochemical levels of grazing beef cows were similar to drylot feeding cows except of concentration of urea nitrogen. Italian ryegrass (Lolium multiflorum Lam) showed very good quality with high crude protein (about 20 percentage) in winter. And so, suckler cows gained live weight in winter and suckling calves were showed very high growth rate (daily gain was about 1.0 kg). Total live weight gains of grazing cows were higher than those of drylot feeding cows. Postpartum reproductive performances of grazing cows were …

Forage Management For Extending The Grazing Season, David W. Koch, C. M. Lux, J. W. Flake

IGC Proceedings (1977-2023)

Studies were conducted to determine ways to extend grazing season with forages adequate to meet the needs of grazing animals and to reduce the cost of livestock production. Perennial grasses were swathed, windrowed and left in the field until they were winter-grazed with bred heifers. Corn (Zea mays L.) was stockpiled for winter grazing with lambs and ewes. Windrowed grasses increased in acid detergent fiber (ADF) and neutral detergent fiber (NDF) compared with stored hay, but crude protein content, heifer weight gain and body condition change was similar for both forages. An economic value of $218 ha^-1 from …

Mechanization: Planning And Selection Of Equipment, C. A. Rotz

IGC Proceedings (1977-2023)

The planning and selection of equipment for harvest and handling of forage crops can greatly impact the performance and profitability of a farm. The type and size of equipment used affects the harvested yield and nutritive value of the forage crop as well as production costs. Through interactions with other parts of the farm, these effects can impact market value of the forage, animal intake and performance, delays in other farm operations, other production costs, and ultimately farm profit. Standard procedures and relationships have been developed for determining the most appropriate equipment for a given production system. Because of the …