Physical Sciences and Mathematics Commons^™

Push-Pull Farming System Helps Insure Smallholder Maize Production Under Climate Change, Yann Clough, Wilhelm May, Timothy Luttermoser, Dickens Nyagol, Nikolaos Alexandridis, Frank Chidawanyika, Mattias Jonsson, Charles A.O. Midega, Katja Poveda, Zeyaur R. Khan

All Peer-Reviewed Publications

Agroecological approaches harnessing in-field biodiversity have been highlighted as a sustainable way to reduce yield gaps, but long-term assessments of their ability to buffer production from weather extremes and increasing interannual and intraseasonal climate variability are scarce. Here, we analyze a 12-year dataset from 642 control vs. push-pull maize field pairs in western Kenya, where long-term climate trends include increasing temperatures and intensifying drought and rainfall. In push-pull, maize is intercropped with a fodder legume that improves soil fertility, suppresses weeds, and deters pests, and is bordered with fodder grasses attracting and suppressing the pests. We assess interactions between push-pull …

Toward Optimizing Fruit Production In Utah Soils: Apple Salt Tolerance Screening And Tart Cherry Fertility Management, Kaitlin Dabbs

All Graduate Theses and Dissertations, Fall 2023 to Present

Fruit production in Utah can be challenging due to local climate and soil conditions. Tart cherries and apples are major fruit crops in Utah, and improvements to these cropping systems would be beneficial for farmers and local consumers. Two experiments were conducted to evaluate desired improvements for these crops. The first study looked for salt tolerance in ten new apple rootstocks. Salty soils can be found throughout the state limiting the land suitable for apple production. When grown in salty soils apple trees often have reduced growth and production potential. A specialized drip irrigation system was constructed in a greenhouse …

Harnessing Digital Twin (Dt) Technology For Food Security And Climate Resilience In Sub-Saharan Africa (Ssa), Henri E.Z. Tonnang, Francis Chianu, Siyabusa Mkuhlani, Francis Muthoni, John Michael Humphries Choptiany, Franck B.N. Tonle, Bonoukpoe M. Sokame, Mercy Lung’Aho

All Peer-Reviewed Publications

Sub-Saharan Africa (SSA) faces chronic food insecurity despite possessing approximately 60% of the world’s uncultivated arable land. Field trials generate evidence but are costly and insufficiently scaled to address accelerating climate and demographic pressures. Digital twin (DT) technology, defined as the continuous, bidirectional virtual replication of physical systems using real-time data, supports monitoring, modelling, and optimisation of agrifood systems. To our knowledge, however, no published synthesis has examined DT agriculture research through the lens of SSA food systems or smallholder farming realities. A PRISMA-compliant systematic review was conducted across bibliographic databases using a pre-defined Boolean search and adapted PICOS eligibility …

Cropland Change And Prime Farmland In Calloway County, Kentucky, 2015–2025: A Gis Analysis Of Corn And Soybean Fields, Shiba Hari Dhakal Shiba

Scholars Week

Understanding where cropland change occurs relative to soil quality helps indicate whether farmland is being used on the most productive land. This study used GIS-based change detection analysis to evaluate changes in corn and soybean fields in Calloway County, Kentucky, between 2015 and 2025 and to test whether new corn and soybean fields were located on prime farmland. USDA Cropland Data Layer maps for 2015 and 2025 (30 m resolution) were reclassified into seven classes and compared in ArcGIS Pro, and the results were overlaid on USDA NRCS gSSURGO farmland classification. Combined corn and soybean area declined about 19% from …

Carbamate Toxicosis In Carnaby’S Cockatoos (Zanda Latirostris) In A Drying Climate, A Le Souef, Z M. Kissane, David Forshaw, K J. Riley, K Payne, T Hawkins, J Coggins, J M. Shephard, R Vaughn-Higgins, K S. Warren

Climate Science Research Articles

Pesticide exposure poses a growing threat to the health of wild avian populations worldwide. This report documents the first detections of agricultural chemicals in the tissues of wild Carnaby’s cockatoos (Zanda latirostris) in Western Australia. The events, characterised by morbidity and mortality, occurred in a national park near Perth, following periods of elevated summer temperatures over two seasons. Toxicological analysis of liver and digestive tract contents identified multiple pesticides and an herbicide, including methomyl, a highly toxic carbamate insecticide. Hot weather conditions preceding the events potentially increased the cockatoos’ use of alternative water sources for drinking, such as those in …

Physical Soil Health Indicators In Paired Certified Organic And Conventional Farms: A Multi-Case Study In The Philippines, Victorino A. Bato, Gina Villegas Pangga

The Philippine Agricultural Scientist

There is a common perception that organic products and practices are good for the health of consumers, plants, the environment, and particularly the soil. In the Philippines, organic agriculture was enacted into law (i.e., Republic Act No. 10068) in order to encourage farmers to shift to organic farming and reap its benefits, including better soil health through improved soil physical properties. This study compared certain soil physical properties of certified organic farms in the Philippines with those of a conventional cropping system. Results showed significantly higher soil aggregate stability (high values of percent water-stable aggregates and mean weight diameter, both …

Bathurst Burr And Its Control, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity factsheets

Bathurst burr (Xanthium spinosum) is a declared pest in Western Australia (WA). This factsheet describes the nature of the plant, requirements land owners/occupiers must adhere to, control methods, and how to search, detect, and report it.

Bathurst burr is a summer growing annual shrubby plant originating in South America. In south west Australia, some mature plants survive well into winter, with the result that burrs may be found for most of the year. The weed spreads entirely by burrs, which are usually carried by people or animals, attached to clothes, fur, or other fibre by their hooked spines. They may …

Noogoora Burr And Its Control, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity factsheets

Noogoora burr, also known as cocklebur (Xanthium strumarium), is a declared pest in Western Australia (WA). This factsheet describes the nature of the plant with links to requirements that land owners/occupiers must adhere to and control methods.

Native to western United States of America. Locally abundant in parts of the Kimberley, especially near water courses. Occasionally found in the South West region of WA.

Collecting Holistic Evidence On Agroecology Performance To Accelerate Sustainable Food System Transitions, Sarah K. Jones, Andrea Cecilia Sánchez, Chris Dickens, Matthias S. Geck, Chaturangi Wickramaratne, Veronique Alary, Peter Bolo, Dennis Junior Choruma, Somphasith Douangsavanh, Modou Gueye Fall, Gatien Falconnier, Shweta Gupta, Chris Kettle, Smitha Krishnan, Sylvia Nyawira, Guillermo Orjuela-Ramirez, Boko Michel Orounladji, Piedad Pareja, Telma Sibanda, Christine Lamanna

All Peer-Reviewed Publications

A growing body of research shows the potential of agroecology for enabling a shift to planet-friendly and socially just agrifood systems through context-specific transition pathways. We conduct a scoping review to identify and evaluate the potential of 42 existing agroecology adherence and/or agricultural performance assessment tools to generate credible, legitimate, salient and transferable evidence to inform these transitions. Results show that while multiple relevant tools exist, each of them can be strengthened in at least one area. While most tools are transferable (low time and resource requirements) and have legitimacy (open access with transparent methods), tools have variable saliency (holistic …

Never Say Never: The Interdependence Of No-Till And Strategic Deep Tillage In Sustainable Production Systems, Therese Mcbeath, Stephen Davies, John A. Kirkegaard

Grain and Other Field Crops Research Articles

No-till (NT) farming systems are a defining feature of modern conservation agriculture (CA), providing benefits for soil and water conservation, operational efficiency, and resource use efficiency. However, long-term NT adoption across Australian dryland cropping systems has also intensified inherent and emergent soil constraints, including subsurface compaction, topsoil water repellence, acidity, and nutrient stratification. These constraints limit crop water use and yield potential. In the sandy soils of southern and western Australia, strategic deep tillage (SDT) has been developed in otherwise NT systems to alleviate these constraints. Advances in machinery design and controlled traffic systems have enabled deeper, more effective amelioration …

Oregon State Rank Assessment For Schweinitz's Cyperus (Cyperus Schweinitzii), Nora Dunkirk

Institute for Natural Resources Publications

Oregon state conservation status assessment for Schweinitz's cyperus (Cyperus schweinitzii) using NatureServe methodology, 2026.

Nasa’S Ecostress Satellite Reveals Widespread Midday Depression In Ecosystem Evapotranspiration, Jingyi Bu, Jingfeng Xiao, Joshua B. Fisher, Yiqi Luo

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Plants often exhibit a midday depression in water use (i.e., transpiration), reflecting a constraint on their ability to sustain maximum water transport, which may occur at the cost of reduced photosynthesis. Eddy covariance observations and geostationary satellites cannot quantify this widespread phenomenon globally while resolving fine-scale spatial variability. Using evapotranspiration measurements from the ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) and machine learning, we quantify the global distribution of midday depression in evapotranspiration. Midday depression primarily occurs during peak-growing seasons in temperate zones and dry periods in the tropics, with a morning shift of the peak evapotranspiration time …

Oregon State Rank Assessment For Koehler's Rockcress (Boechera Koehleri), Lindsey K. Wise, Gabriel Campbell

Institute for Natural Resources Publications

Oregon state conservation status assessment for Koehler's rockcress (Boechera koehleri) using NatureServe methodology, 2026.

The Effectiveness Of Bacillus-Coated Npk Fertilizer On Broccoli Growth, Nutrient Status, Rhizosphere Bacillus Population, Yield, And Flower Quality, Betty Natalie Fitriatin, Rara Rahmatika Risanti, Reginawanti Hindersah, Fasa Aditya Hanindipto, Gita Bina Nugraha

Jurnal Kultivasi

Efforts to increase the availability of macronutrients in soil have relied on inorganic fertilization, particularly NPK fertilizers. However, global challenges in the fertilizer raw material supply chain, including price fluctuations and availability, are driving the need for more efficient and sustainable fertilizer alternatives. The field experiment was conducted in Baruajak, Lembang District, West Java, Indonesia, to evaluate the effectiveness of Bacillus-coated NPK fertilizer on broccoli (Brassica oleracea var. italica) growth, nutrient status, rhizosphere Bacillus population, yield, and flower quality. The experiment used a randomized complete block design with 15 fertilizer treatments and three replications. Treatments consisted of two coated NPK …

The Effect Of Silica-Enriched Rice Husk Biochar And Npk Fertilizer On Soil Total Nitrogen, Nitrogen Uptake, And Yield Of Lowland Rice, Emma Trinurani Sofyan, Oviyanti Mulyani, Ania Citraresmini, Meddy Rachmadi, Kharmelia Sandra Livia

Jurnal Kultivasi

Rice production in Indonesia increasingly relies on agricultural intensification, which can accelerate soil degradation and reduce fertilizer-use efficiency. Therefore, sustainable soil management is needed to maintain soil fertility. Silica-enriched rice husk biochar (biochar-silica) is a promising soil amendment because it improves soil properties and nutrient retention. This study evaluated the effects of biochar-silica and NPK fertilization on soil total nitrogen, nitrogen uptake, and yield of lowland rice (Oryza sativa L.). The experiment was conducted from September 2025 to January 2026 using a two-factor randomized block design with nine treatment combinations and three replications. The treatment consisted of three levels of …

Effects Of Ab Mix Hydroponic Solution And Ameliorant Mixtures On Cayenne Pepper Growth And Yield In An Inceptisols, Tien Turmuktini, Betty Natalie Fitriatin, Tualar Simarmata, Firda Widayanti, Nuryanti, Lia Amalia, Elly Roosma Ria, Linlin Parlinah

Jurnal Kultivasi

Cayenne pepper (Capsicum frustescens L.) cultivation faces several problems, including acidic pH and inadequate nutrient management. These problems can be addressed by using a mixture of various ameliorants and AB mix nutrient solutions. This study aimed to determine the effect of ameliorant mixture dosage and AB mix solution concentration on soil chemical properties, growth, and yield of cayenne pepper. The experiment used a randomized block design, consisting of two factors: nutrient solution concentration and ameliorant dosage. The factor of nutrient solution concentration consisted of four levels, i.e., 700, 1000, 1300, and 1600 ppm, while the factor of ameliorant dosage also …

Modeling The Clonal Rosette Composition Of A Bromeliaceae Genet: A Combinatorial Approach, Layla K. Lammers, Erin N. Bodine

Spora: A Journal of Biomathematics

Bromeliaceae, a neo-tropical plant family encompassing over 3,000 species, exhibit two modes of reproduction: sexual reproduction via flowers and seeds, and asexual reproduction via genetically identical clonal rosettes. The vegetative bodies of bromeliads form rosettes with new leaves emerging from the center and clonal rosettes emerging above a single leaf in the rosette, resulting in a genetic individual consisting of a seed-grown rosette and multiple iterations of clonal rosettes. This research develops a combinatorial model of probability that a single genetic individual will include at least n clonal rosettes when a single rosette can produce at most 1 or 2 …

Oregon State Rank Assessment For Deer-Cabbage (Nephrophyllidium Crista-Galli), Lindsey K. Wise

Institute for Natural Resources Publications

Oregon state conservation status assessment for Deer-cabbage (Nephrophyllidium crista-galli) using NatureServe methodology, 2026.

Dry After-Ripening Increases Germination Of Critically Imperilled Physaria Thamnophila (Zapata Bladderpod), Christopher A. Gabler, Jerald T. Garrett

School of Earth, Environmental, & Marine Sciences Faculty Publications

Effective endangered plant conservation and recovery require empirical knowledge of seed dormancy release and responses to post-collection handling, yet such information is lacking for many rare taxa. Physaria thamnophila (Zapata bladderpod; Brassicaceae), a critically imperilled (G1) species endemic to southern Texas, USA, is poorly studied, and basic questions regarding seed storage and germination remain unresolved. We evaluated the effects of short-term cool-storage duration (14–180 d), storage temperature (refrigeration vs. freezing), dry after-ripening and maternal plant identity on germination probability and timing in P. thamnophila. Dry after-ripening and increased cool-storage duration consistently increased germination and shortened germination time, whereas storage temperature …

Ammonium Phosphate Fertilizers Are A More Effective Phosphorus Source Than Superphosphate For Wheat Grown On Acidic Gravelly Soils, Craig A. Scanlan, Raj Malik, Fien Degryse, Andrew Van Burgel, Mike J. Mclaughlin

Grain and Other Field Crops Research Articles

Selecting the most effective phosphorus (P) fertilizer source is essential for maximizing crop yields. However, there is little information to guide the choice between the widely used soluble granular sources: ammonium phosphates and superphosphates. The aims of this study were to examine whether there are differences in wheat (Triticum aestivum L.) grain yield response to ammonium phosphate and superphosphate fertilizers in field conditions, and if these differences relate to diffusion of P from fertilizer granules. Two field experiments were conducted on acidic gravelly soils in Western Australia where P deficiency occurs to compare wheat growth response to P applied …

Optimizing Urban Forestry Through Green Infrastructure: Tree Health And Water Retention In Ciudad Juarez Rain Gardens, Tomas Rogelio Lizarraga Ruiz

Open Access Theses & Dissertations

Urban green spaces (UGS) in arid regions face significant challenges due to water scarcity and extreme thermal demand. This study evaluates the efficacy of Nature Based Solutions (NBS), rain gardens and median strips, in enhancing the physiological resilience of urban trees in Ciudad Juárez, Mexico. Using a comparative framework, the research monitored a native evergreen (Dermatophyllum secundiflorum) and an introduced deciduous species (Morus sp.) across six planting treatments. Statistical analysis reveals that green infrastructure (GI) acts as a critical physiological accelerant. Trees situated within rain gardens and medians significantly outperformed those in restricted pot and sidewalk settings, maintaining higher stomatal …

Reconstructing Stand-Age Structure In A Wet Miombo Woodland Using Dendrochronology, Zambia, Clara Tiyembekeze Zulu

All-Inclusive List of Electronic Theses and Dissertations

Dendrochronological research in tropical Africa has remained limited, leaving critical gaps in stand-age structure and climate-growth relationships in seasonally dry tropical woodlands. This study reconstructed stand-age structure and assessed climate sensitivity in the wet Miombo woodland of African Explosives Limited (AEL) forest, Copperbelt Province, Zambia. Field sampling was conducted during four African Dendrochronology Fieldschools (2021-2024) using a Modified Variable Area Transect (MVAT) design across nine plots. The series intercorrelation was 0.351; the average mean sensitivity was 0.423. The oldest tree was 170 years old, and more than 70% of the sampled species showed potential for dendrochronology. Markhamia obtusifolia was the …

Performance Of The Denitrification-Decomposition Model In Simulating Agronomic Properties And N2o Emissions Under Smallholder Climate-Smart Farming Systems, Esphorn Kibet, Collins M. Musafiri, Milka Kiboi, Onesmus K. Ng'etich, David K. Kosgei, Abdirahman Zeila, Franklin Mairura, Felix K. Ngetich

All Peer-Reviewed Publications

The DeNitrification-DeComposition (DNDC) model is a crucial tool for estimating soil greenhouse gas fluxes and understanding soil-plant interactions. This study evaluates the performance of the DNDC model in simulating soil temperature, moisture, crop yield, and nitrous oxide (N2O) fluxes across different land utilization types in Western Kenya. The land utilization types included: i) agroforestry M (agroforestry with Markhamia lutea, ii) sole sorghum, iii) agroforestry L (agroforestry with Leucaena leucocephala), iv) sole maize, and v) grazing Land, each replicated thrice. Fertilizer and manure were applied as part of the management practices, with manure applied at 2t ha⁻¹. Soil greenhouse …

Land Condition Standards For The Western Australian Nullarbor Pastoral Region, Peter-Jon A. Waddell, Wayne J. Fletcher

Natural resources published reports

This report outlines the quantitative land condition standards that define acceptable pastoral land condition for the Western Australian part of the Nullarbor, to meet the regulatory requirements of the Land Administration Act 1997 and the Soil and Land Conservation Act 1945.

The Department of Primary Industries and Regional Development is developing regional-level pastoral land condition standards for Western Australia as a critical component of the Framework for sustainable pastoral management – revised edition (Fletcher 2022), the purpose of which is to address the Office of the Auditor General’s recommendations to improve the management of pastoral lands in WA …

Technological Behaviour Of Pellets Containing Dried Green Crop, Christian Furll

IGC Proceedings (1977-2023)

Pelleted dried green crop presents essential advantages compared to chaff and meal as processing forms. Normally, the solidity of the pellets does not exceed the values required by animal feeding. Abrasion resulting from turnover processes is at present too high, particularly for the discharge of bins. Belt conveyors, vibrating conveyors, and bucket elevators are suitable to convey pellets. Storage of pellets over long periods has to be done by respecting prescribed climate conditions. Zones with excessive portion of abraded par­ticles in the storing pile are a preferred cause for self-heating. Slit-type dosing units as well as dosing units equipped with …

Results Of Comparative Investigations Into The Chevving And Ruminating Activities Of The Dairy Cow Fed Dried Forage From Grass And Leguminous Crops, B Piatkowski, S Nagel

IGC Proceedings (1977-2023)

The chewing and ruminating activities were studied of dairy cows fed grass, alfalfa, and straw of different physical forms. An electronic­ally controlled measuring device was applied. When feeding 8 kg of grass hay (32 % crude fibre in dry matter), the ruminating time was 5: 24 and 1 :49 hours (20,712 and 6,982 ruminat­ing movements) for chopped and ground + pelleted forages, respectively. It declined from 1 : 49 to 0: 0 l hours (from 6,929 to 70 move­ments) when hot-air dried alfalfa (23 % crude fibre) was fed in chopped and ground + pelleted forms, respectively. The ruminating time …

Feed Efficiency In Dairy Cows Of Roughages Preserved And Treated In Different Ways, M Zausch, E Boldt

IGC Proceedings (1977-2023)

Trials were conducted with dairy cows to investigate the feed efficiency of grass-clover mixture (wilted silage, silage made of fresh material with addition of foDTiic acid, artifi­cially dried forage, pellets with varying portions of straw). The results obtained allow to draw the following conclusions:

As regards dry matter intake, digestibility, and feed efficiency, grass-dover for wilted silage should be wilted to give a OM content not exceeding 40 %.

Pelleting artificially dried grass-clover mix­ture and its use in mixed rations together with other separately pelleted components should be avoided.

The best feed efficiency is reached when dried grass-clover is converted …

The Influence Of Dried And Ensiled Grass On Rumen Fermen­Tation, J Voigt, B Piatkowski

IGC Proceedings (1977-2023)

Rumen-fistulated cows were used to study the influence of the forage preservation technique on rumen fermentation and holdup time of the feed in the rumen. Cocksfoot (Dactylis glomerata) preserved as wilted silage or dried green crop was fed in the following variants: wilted silage alone; wilted silage + sugar beet + protein supplement; dried green crop alone; dried green crop + sugar beet + protein supplement. As compared with dried green crop, the shares of true protein and sugar in wilted silage were reduced from 9.8 • to 6.4 '.'I􀉧 and from 7.7 to 1.8 %in DM, respectively. In comparison …

Changes In Feeding Value Of Preserved Grass And Legumes By The Action Of High Temperatures, R Prym, F Weissbach

IGC Proceedings (1977-2023)

High temperatures acting on grass and legumes during preservation and storage, cause nutrient digestibility to deteriorate. Protein digestibility is likely to be most strongly affected. Digest­ibility measurements were performed on sheep to estimate the extent of heat damage suffered by dried green forage and silages. Various laboratory methods were applied for record­ing. such damage. The detennination of the acid-detergent insoluble crude protein portion proved a very suitable approach.

Growth And Nitrogen Retention Of Lambs Fed Alfalfa Dehy­Drated At Different Temperatures, H K. Goering

IGC Proceedings (1977-2023)

Alfalfa was dried at four temperatures ranging from 60 to 180 °C in two experiments to evaluate the effect on composition, diet di­gestibility, and growth by lambs. In Experi­ment I, the alfalfa was supplemented with 0.6 % salt and pelleted. In Experiment 2, alfalfa was supplemented with 24.4 % starch, 18.5% straw, 6% cane molasses, 0.5% sodium phosphate, and 0.6 % salt so that total nitrogen intake was not in excess of the protein require­ment for growth of the lambs. Cell wall, acid­detergent fiber, lignin, acid-detergent insoluble nitrogen, and pepsin insoluble nitrogen in­creased in the alfalfa dried at 180 °C. …