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Full-Text Articles in Physical Sciences and Mathematics

Changes In Physico-Chemical Properties Of A Sandy Loam Soil Depending On The Particle Size Of Hazelnut Shell-Derived Biochar, Damla Bender Özenç, Ceyhan Tarakçioğlu, Funda Irmak Yilmaz, Selahattin AygüN Dec 2023

Changes In Physico-Chemical Properties Of A Sandy Loam Soil Depending On The Particle Size Of Hazelnut Shell-Derived Biochar, Damla Bender Özenç, Ceyhan Tarakçioğlu, Funda Irmak Yilmaz, Selahattin AygüN

The Philippine Agricultural Scientist

This study evaluated the effects of hazelnut shell-derived biochar particle sizes on the soil’s physical and chemical properties, and on various nutrient contents present in the sandy loamy soils. For this purpose, an incubation experiment in the plastic high tunnel has been performed under sixteen treatments (control-only soil), and at four incubation times (30, 60, 90, and 120 d), by using three different biochar sizes (≤ 1, 1 - 2, and 2 - 4 mm). The addition of 1 - 2 and 2 - 4 mm biochar during the incubation time decreased the bulk density in the soil by 26%. …


Numerical Quantification Of Surface Runoff And Soil Erosion Using Pcraster, Victorino A. Bato Dec 2023

Numerical Quantification Of Surface Runoff And Soil Erosion Using Pcraster, Victorino A. Bato

The Philippine Agricultural Scientist

Surface runoff and soil erosion of the Upper Lagawe River Sub-watershed, Ifugao Province, Philippines were quantified using Geographic Information Systems (GIS)-based numerical simulation. PCRaster software was used as a framework for the model. Manning’s and Rose, and Freebairn’s Equations were utilized to compute surface runoff velocity and sediment mass. Analysis and comparison of the measured and predicted streamflow yielded a mean Nash and Sutcliffe Efficiency Index of 0.70, a mean percent bias of -8.38%, and a mean root mean square error (RMSE) of 0.16. Based on the model, super typhoon Lando (international name: Koppu) generated an estimated surface runoff volume …


The Effect Of Amf-Cacao Association On Varying Physicochemical, Nutrient, And Biological Soil Parameters In An Agroforest System, Diana P. Paguntalan, Nelly S. Aggangan, Inocencio E. Buot Jr. Dec 2023

The Effect Of Amf-Cacao Association On Varying Physicochemical, Nutrient, And Biological Soil Parameters In An Agroforest System, Diana P. Paguntalan, Nelly S. Aggangan, Inocencio E. Buot Jr.

The Philippine Agricultural Scientist

The increasing interest in sustainable methods in agroforestry directs the attention of many to arbuscular mycorrhizal fungi (AMF) for their role in maintaining or improving overall plant health and nutrition of many plants including cacao (Theobroma cacao L.) trees. The effects of different treatments of AMF and other soil amendments applied singly or in combination on physicochemical properties, nutrient levels, spore count, and rhizosphere microbial counts, were investigated and compared across different sampling periods of varying climatological conditions in an agroforest system. Results showed that there was a significant effect on the N content using the different treatments. The …


Dry Matter Production Of Two Rice Cultivars With Contrasting Root Plasticity Expression Under Different Topographic Conditions Subjected To Soil Moisture Fluctuation, Stella Owusu Nketia, Roel Rodriguez Suralta, Yoshiaka Inukai, Shiro Mitsuya, Mana Kano Nakata, Peter Amoako Ofori, Dinh Thi Ngoc Nguyen, Akira Yamauchi Jun 2023

Dry Matter Production Of Two Rice Cultivars With Contrasting Root Plasticity Expression Under Different Topographic Conditions Subjected To Soil Moisture Fluctuation, Stella Owusu Nketia, Roel Rodriguez Suralta, Yoshiaka Inukai, Shiro Mitsuya, Mana Kano Nakata, Peter Amoako Ofori, Dinh Thi Ngoc Nguyen, Akira Yamauchi

The Philippine Agricultural Scientist

In rainfed lowland rice fields characterized by sloping terrains and the presence of a hardpan in a flat topography, plants are often exposed to soil moisture fluctuation (SMF) stress due to erratic rainfall patterns. Root plasticity is one of the key traits that play important roles in plant adaptation under such conditions. In this study, two contrasting genotypes, KDML105 and IRAT109, were examined to quantify the expression of plasticity in root branching at different positions in the toposequence (TP) and in a flat topography with a hardpan, both without a groundwater table, and subjected to SMF. Results showed that KDML105 …


Corn Cob And Corn Husk Biochars Enhance The Growth Of Corn (Zea Mays L.) In Fertilized Clay Loam Soil, Arsenio D. Bulfa Jr, Gina Villegas Pangga, Amparo M. Wagan Jun 2023

Corn Cob And Corn Husk Biochars Enhance The Growth Of Corn (Zea Mays L.) In Fertilized Clay Loam Soil, Arsenio D. Bulfa Jr, Gina Villegas Pangga, Amparo M. Wagan

The Philippine Agricultural Scientist

Biochar is a carbon (C) rich material that improves soil quality, increases crop yield, and is produced from biomass pyrolysis under a limited oxygen environment. An experiment laid out in a split-plot, a completely randomized design (CRD) and was conducted to investigate the growth responses of corn-to-corn cob biochar (CCB) (15 t ha-1), and corn husk biochar (CHB) (15 t ha-1) in a Lipa clay loam soil (Typic Eutrudepts) applied with organic fertilizer (OF) (10 t ha-1) and inorganic fertilizer [recommended rate (RR):120 N;60 P2O5-60; K2O …


Natural And Anthropogenic Factors Affecting The Development Of Two Highland Agricultural Soils Of Bukidnon, Philippines, Guadalupe D. Calalang, Laurent Bock, Gilles Colinet, Vincent Hallet, Peter Walpole Jun 2023

Natural And Anthropogenic Factors Affecting The Development Of Two Highland Agricultural Soils Of Bukidnon, Philippines, Guadalupe D. Calalang, Laurent Bock, Gilles Colinet, Vincent Hallet, Peter Walpole

The Philippine Agricultural Scientist

This research was conducted in two highland areas of Bukidnon, Philippines: Miarayon, a sub-catchment of the upper Cagayan de Oro River; and Bendum, a sub-catchment of the upper Pulangui River. Due to their pyroclastic parent rock materials, soils in the upper Cagayan de Oro are classified as Andic Cambisol in open and convex positions, and Andic Umbrisol in concave and depressed positions. Soils in the upper Pulangui are classified as Pisoplinthic Acrisol, Ferralic Nitisol, and Acric Nitisol in areas with ultramafic rock parent materials, and Haplic Cambisol with pyroclastic deposits. Element contents in rocks were congruent to the total soil …


Finite Element Analysis Of A Coconut (Cocos Nucifera L.) Climbing Mechanism, Arjay O. Afan, Omar F. Zubia, Adrian A. Borja, Ralph Kristoffer B. Gallegos Jun 2023

Finite Element Analysis Of A Coconut (Cocos Nucifera L.) Climbing Mechanism, Arjay O. Afan, Omar F. Zubia, Adrian A. Borja, Ralph Kristoffer B. Gallegos

The Philippine Agricultural Scientist

A coconut climber mechanism was subjected to Finite Element Analysis (FEA) to improve its overall design and analyze its strength characteristics. The von Mises stress, total deformation, and factor of safety were evaluated using static structural analysis for the seat and pedal assemblies of the mechanism. The design has a minimum yielding factor of safety of 7.03 for the seat assembly and 12.09 for the pedal assembly. If aluminum is used as an alternative to steel, the prototype's weight can be reduced to at least 64.56% without compromising its strength properties. The weight reduction by using aluminum is expected to …


Air And Air-Steam Gasification Of Coconut Shell In A Fluidized Bed, Keynty Boy V. Magtoto, Rossana Marie C. Amongo, Sergio C. Capareda, Ronaldo B. Saludes Mar 2023

Air And Air-Steam Gasification Of Coconut Shell In A Fluidized Bed, Keynty Boy V. Magtoto, Rossana Marie C. Amongo, Sergio C. Capareda, Ronaldo B. Saludes

The Philippine Agricultural Scientist

Coconut shells’ abundance in tropical countries, along with its high volatile combustible matter (83.51%) and energy content (18.68 MJ kg-1) make it a good biomass resource and a promising feedstock for gasification. In gasification, different mediums such as air, steam, oxygen, or their combinations can be used to react with the solid carbon and heavy hydrocarbons of biomass. Hence, the effects of using an air-steam mixture as a gasifying agent for the bench-scale fluidized bed gasification of coconut shells were studied. The steam-to-carbon ratio (SCR) was varied to evaluate its effect on the resulting syngas quality and gasification …


The Use Of Open Data Kit (Odk) In Characterizing The Cacao Industry Sites In Panay Island, Rhea J. Subong-Espina, Reynold D. Tan, Christine Mae D. Hernando Mar 2023

The Use Of Open Data Kit (Odk) In Characterizing The Cacao Industry Sites In Panay Island, Rhea J. Subong-Espina, Reynold D. Tan, Christine Mae D. Hernando

The Philippine Agricultural Scientist

Cacao is one of the world's most valuable export commodities and cash crops. Western Visayas, along with the other regions in the Philippines, has committed to participate in national efforts to strengthen the production capacity of the cacao industry and address prospects and opportunities for the industry growth and development. This paper presents the results of a region-wide study that mapped out and assessed key cacao-producing areas in Western Visayas, specifically Aklan, Antique, Capiz, and Iloilo. The study sought their current production levels, important agricultural properties of farming areas, production densities, and growth potentials. Geospatial data was generated, analyzed, and …


Effects Of Drying Temperature And Tempering Duration On Hybrid Rice Seed Germination, Thin-Layer Drying Characteristics, And Power Requirement, Rina A. Bawar, Joanne P. Foliente, Kevin F. Yaptenco, Mitchie Ann L. Cabiles Mar 2023

Effects Of Drying Temperature And Tempering Duration On Hybrid Rice Seed Germination, Thin-Layer Drying Characteristics, And Power Requirement, Rina A. Bawar, Joanne P. Foliente, Kevin F. Yaptenco, Mitchie Ann L. Cabiles

The Philippine Agricultural Scientist

This study presents the results of thin-layer drying tests for hybrid rice seeds. The independent factors were drying air temperature (45, 55, and 65 °C) and tempering duration (1, 2, and 4 h), while the dependent parameters were seed germination and drying characteristics, including drying rate, total and effective drying operation times, and power requirement. Considering one hybrid and 3 mo storage period after drying, the results showed that samples continuously dried at 45 and 55°C resulted in 91 and 86% germination percentages, respectively, which were above the acceptable Philippine national standard of at least 85%. However, when tempered for …


Moving Towards Sustainable Mining Communities: The Case Of The Community-Led Non-Cyanide Non-Mercury Cold Extraction Method (Clinn-Cem) In Compostela Valley, Philippines, Rowee Joy S. Decena Jan 2023

Moving Towards Sustainable Mining Communities: The Case Of The Community-Led Non-Cyanide Non-Mercury Cold Extraction Method (Clinn-Cem) In Compostela Valley, Philippines, Rowee Joy S. Decena

Journal of Public Affairs and Development

The small-scale mining industry and communities are left behind in terms of development. They are confronted with economic, environmental, and social problems. Thus, to address these problems and move towards sustainable development, this social development research explores how CLINN-GEM, as a technological innovation, contributes to achieving sustainable mining communities. The researcher employs a single case study approach and adopts qualitative methods in data gathering and analysis. Data gathering methods include document reviews, guided tour, key informant interviews with seven informants, focus group discussions with the operations group and the members of the project staff, and a structured learning exercise with …