Water Capacity Research Articles

The effect of underground drainage on peat meadows and inactivation of the drainage in an attempt to restore these meadows, which failed as it reduced the ability of soils to retain water

Drainage is often used to increase agriculture production, but it has adverse effects on biodiversity and water retention. Here, the effect of subsurface pipe drainage on peat meadows near Senotín (Czechia), which were drained from the mid-1980s to 1990s, was studied. Attempts were made to restore the peat meadows by damming drainage pipes using clay-filled trenches in 1996. In this case study, the effect on the depth of the water table, soil water retention, infiltration and soil temperature were recorded. Measurements of the original peat meadow (undrained site), drained meadow (drained site) and restored meadow (restored site) before restoration and two decades after restoration were recorded. The water table in undrained areas was higher than at drained and restored sites, indicating that drainage had lasting effect on drained and restored sites. Infiltration was lowest at the undrained site, greater at the drained site, and highest at the restored sites. Field water capacity was lowest at the restored site, greater at the drained site and highest at the undrained site. Soil water content at maximum saturation was lowest at the restored site, greater at the drained site and highest at the undrained site. Soil temperature was highest at the restored site with no significant difference between the undrained and drained sites. Soil moisture levels were highest at the undrained site and lowest at the drained site. In addition, the undrained and restored sites did not differ significantly in soil moisture content. In conclusion, restoration did not have a significant effect on the level of the water table, initiation of peat formation or ability of soil to hold water.

SIMULATION MODELING AND PRACTICAL USE OF THE HYDROLOGICAL FUNCTION OF DETRITUS IN SOIL ENGINEERING TECHNOLOGIES

The high water retention and water capacity functions of detritus determine its potential hydrological signifi cance in the formation of the water regime of soils and phytoproductivity of forest landscapes. Using computer modeling of water exchange in the “soilplantatmosphere” HYDRUS1D system, we preliminary studied the hydrological function of detritus for water retention of precipitation and root water consumption at different amounts and variants of the arrangement of detritus layers in the soil profi le. The soil structures designed on the basis of this information for sustainable afforestation with increased carbon sequestration demonstrated in field experiments with water balance monitoring high eficiency in optimizing the water retention capacity of the soil and roots water consumption of the test crop (Glauca spruce) with a 23fold reduction in unproductive water losses and a 1.5-2fold increase in the current plant growth relative to untreated control. The physical mechanism of the detritus hydrological function is the formation of capillary barriers blocking evaporation and capillary resorption of soil water due to due to surface accumulation (forest litter) or placement in layers inside the soil (peat layers in constructosems).

Flow Simulation Study on Bed Bath for Bedridden Patient

Easy tasks such as showering or bathing independently are impossible for a bedridden individual. This paper presents a comprehensive study on designing an easy shower specifically tailored for bedridden patients. The challenges bedridden individuals face in maintaining personal hygiene are highlighted, emphasizing the importance of a suitable bathing system to enhance their quality of life. The proposed design aims to address these challenges and improve caregiving efficiency. The chosen methodology involves a weighted decision matrix to select the optimal design, followed by flow simulation using SolidWorks Flow Simulation software to evaluate its performance. The paper's objectives include designing an efficient easy shower model, assessing its performance via simulation, and analyzing the impact of various velocity settings on its functionality. Three design concepts were proposed, with Design A selected as the optimal choice due to its lightweight, high water capacity, ease of handling, and low production cost. Modifications were made to enhance its water pressure efficiency. The simulation encompassed different velocity settings, with flow trajectories analyzed within the tank and at the water outlet. These boundary conditions included analysis type (internal), fluids (water), default wall thermal condition (adiabatic wall), pressure (101325 Pa), temperature (293.2 K), and velocity in the Y direction (5 m/s for water inlet and 0.5 m/s for water outlet). In the first simulation, all the results obtained were within the specified velocity range of 0.5 m/s, 2 m/s, and 5 m/s. The analysis of flow trajectories revealed distinct flow patterns and velocities for different velocity values, indicating stable and controlled environments within the tank and efficient water discharge through the outlet in Design A. However, errors were observed in the water outlet simulation due to the presence of vortices, which impacted the results. Recommendations were made to address these challenges, such as modifying the design to eliminate or minimize vortex effects. In conclusion, this study contributes to the well-being of bedridden patients by proposing an improved bathing mechanism, enhancing caregiving efficiency, and offering insights into design optimization and simulation challenges. The proposed design could have a significant positive impact on the lives of bedridden patients and caregivers.

Opening up the subsoil: Subsoiling and bio-subsoilers to remediate subsoil compaction in three fodder crop rotations on a sandy loam soil

The intensification of modern arable farming has brought on a steady increase of the risk of soil compaction, while simultaneously pushing the impact deeper into the soil profile. In the subsoil, outside the reach of regular tillage operation, it can become exceedingly difficult to deal with compacted layers. Commonly, farmers turn towards mechanical remediation strategies, like subsoiling, to deal with this issue. However, the numerous drawbacks that come with these operations have prompted the search for more sustainable alternatives, like bio-subsoilers, which are deep-rooting plant species with the capacity to penetrate compacted subsoil layers. This study aimed at investigating both mechanical and biological remediation strategies in a side-by-side comparison. The effectiveness of subsoiling and the use of two deep rooting (cover) crops (i.e. alfalfa and fodder radish) as remediation measures to alleviate subsoil compaction was assessed in terms of soil quality indicators, like penetration resistance, bulk density, porosity, plant available water capacity, air capacity and air permeability at 35 and 45 cm depth, and the above- and belowground growth of the main crop. In addition, a combination of both subsoiling and use of deep rooting (cover) crops was included to evaluate the potential role of the latter in protecting the mechanically loosened subsoil from recompaction. This complex comparison was done in three distinct maize-based fodder crop rotations (rotation 1: maize monoculture; rotation 2: maize/winter cereal rotation with fodder radish as cover crop after winter cereal; rotation 3: maize/winter cereal/alfalfa rotation). The study field (sandy loam soil) was selected based on the presence of a highly compacted layer at the interface between topsoil and subsoil (30–50 cm). The experiment demonstrated that subsoiling is an effective remediation measure to disrupt heavily compacted layers in the upper-subsoil, at least in the short-term. The crop response was however highly variable and only positive when the opportunity of reaching the subsoil proved to be advantageous for the crop (i.e. dry season). Besides its high degree of variability between years, the effects also proved to be very short-lived under a standard arable fodder crop rotation. Including deep rooting (cover) crops, like fodder radish and alfalfa, and limiting the initial subsoil disruption helped to partially stabilize the disrupted subsoil and reduce recompaction. Fodder radish and alfalfa penetrated the compacted subsoil without previous disruption by subsoiling. However, this did not lead to a significant improvement of the measured soil physical parameters.

Temporal and spatial variability of physical and chemical properties in reclaimed soil after sulphur borehole mining

Mining contributes to the creation of degraded areas that are difficult to rehabilitate because they are subject to various transformations. Specifically, sulphur mining using the Frasch borehole method causes multidirectional changes of soil properties and thus presents challenges for post-mining rehabilitation. The aim of the current study was to evaluate the effectiveness of agricultural (meadow-type) reclamation and to understand how the soil recovers over time by assessing the spatio-temporal variability of the reclaimed soil after borehole sulphur mining. Selected soil properties and spectral indices based on satellite data were analysed: before reclamation, 3 years after reclamation and 15 years after reclamation. Texture, bulk density, porosity, water capacity, total organic carbon (TOC) and pH were measured and distribution maps of these parameters were generated using kriging. Additionally, maps of spectral indices (Green Normalized Difference Vegetation Index, Normalized Difference Soil Moisture Index, Soil Adjusted Vegetation Index, Enhanced Vegetation Index and Red–Green Index) based on Landsat imagery were created to support the field survey data. The soil revealed high temporal and spatial variability, as evidenced by the distributions of measured parameters and their coefficients of variation at different reclamation stages. Multidirectional remodelling of the soil structure occurred, resulting in changes in the differential porosity, field water capacity, texture, reaction and TOC. Statistically confirmed differences in soil parameters between sampling points were observed. The variability of the physical and chemical parameters at the individual sampling point also differed between the reclamation stages. We observed a general trend towards homogenisation of the spatial distributions of the soil parameters. This was also confirmed by the maps of spectral indices, which showed establishment and development of a continuous vegetation cover and the subsequent improvement of its condition.

Effect of High-Protein and High-Fiber Breaders on Oil Absorption and Quality Attributes in Chicken Nuggets.

Consumption of fried foods is associated with a higher risk of cardiovascular and other diseases; therefore, consumers are looking to reduce fat intake. We evaluated the effect of high-protein breaders and fiber on oil absorption and quality attributes in chicken nuggets, using flour blends (wheat, chickpea, coconut, oil-quinoa-chia), soy protein concentrate, and brewers' spent grain. We evaluated the chemical composition, water and oil retention capacity (ORC), viscosity profile, and flour particle size distribution, along with the developed breaders (Formulation 1 and 2) and a commercial breader (CB), in addition to texture, color, fat, and moisture contents of the fried chicken nuggets prepared with the developed breaders and the CB. The total dietary fiber content (TDF) of the nuggets breaded with only Formulation-1 and CB was determined. Nuggets breaded with Formulation-1 showed lower (p ≤ 0.05) ORC, better moisture retention (67.6%), and more TDF (4.5% vs. 2.3%, p ≤ 0.05) compared to CB-breaded nuggets. Nuggets with Formulation-1 showed the expected texture and color characteristics for fried products. Formulation-1 has the potential to be used as a breader due to its moisture, reduced ORC, and the texture and color it imparts to the fried nuggets, providing higher amounts of nutrients and possible health benefits.

Genome wide association study of Ethiopian barley for terminal drought stress tolerance under field and climate chamber conditions

In order to detect markers for drought stress tolerance, field experiments in Ethiopia were conducted for three years at two naturally drought-prone locations and two optimum moisture locations using 239 Ethiopian barley landraces and 21 barley breeding lines. Furthermore, a climate chamber experiment applying drought stress at different water regimes (70% soil water capacity (WC) for control and 20% WC for drought stress conditions) after flowering was conducted for selected 196 accessions. Results revealed reduced grain biomass by 47% and 80% under field and climate chamber conditions, respectively, as well as significantly (p < 0.05) reduced days to maturity and plant height, in both experimental designs. Based on 10,644 SNP markers, GWAS was conducted to identify marker trait associations (MTA) for drought stress tolerance. For days to maturity, relative chlorophyll content, plant height, number of seeds per spike, thousand kernel weight, and harvest index under field and climate chamber drought stress treatments, 58 significant MTAs were identified. In total, 41.4% of the MTAs were located on chromosome 2H, of which one is very close to the Ppd-H1 flowering locus. These findings underpin the importance of this genome region for drought tolerance. Another MTA on chromosome 1H was detected for days to maturity under field drought stress treatment in the vicinity of the known flowering time ELF3 gene. Additionally, 13 and 3 Ethiopian landraces that tolerate severe and moderate drought stress in climate chamber and field experiments were identified, respectively, using drought indices. The results highlight the tolerance of Ethiopian landraces to different levels of drought stress as well as their potential to be considered in future barley improvement programs.

Liming leads to changes in the physical properties of acidified forest soils

AbstractBackgroundForest liming is a common practice in many German forests, which aims primarily at improving soil chemical properties that have been negatively impacted by acid rain. Effects on physical functions have not yet been studied widely.AimsThe hypothesis of this study is that chemical changes after liming lead to changes in the physical properties of the humus layer and mineral soil.MethodsWe studied soil physical characteristics (water retention characteristics, air and water permeabilities, and conductivities) of limed and adjacent control plots of sandy to loamy, acidified soils under spruce and beech‐dominated stands.ResultsWe found differences between limed and control plots, especially in the humus layer and mineral top soil. Here, air capacity values (representing air‐filled macropores at −6 kPa) have experienced an increase, while available water capacities (representing the sum of dewatered mesopores between −6 and −1500 kPa) were reduced to a variable extent. These changes in pore size distributions affected gas diffusion as well as gas permeability positively. Unsaturated hydraulic conductivity was not affected. Below the top mineral soil, a tendency to a reduced macroporosity and gas permeability was observed, but no clear changes were detected.ConclusionsSmall but significant changes of soil physical properties and functions in the humus layer and top mineral soil are discussed to be an indirect effect of forest liming. Liming improves pH and nutrient availability, which in turn should have stimulated activity and abundance of soil fauna, especially earthworms. Where observed, their activity could explain the observed changes in soil physical properties. We believe that effects below the top soil might be due to mobilization and translocation of soil particles and a clogging of pores, but these depths were only studied at three plots. Compared to common liming practices, however, the investigated sites are characterized by significantly higher lime applications. The effects on practice liming areas in forestry praxis are therefore likely to be smaller than in this study.

The Effect of Different Vegetation Restoration Types on Soil Quality in Mountainous Areas of Beijing

Soil quality is a very important indicator used to assess ecosystem restoration states in terms of vegetation recovery and establishment. Evaluating the soil quality of different vegetation restoration types in mountainous areas of Beijing and identifying their influencing factors would provide a scientific basis and be helpful for vegetation restoration in the future. Six vegetation types (or communities), including Platycladus orientalis (L.) Franco pure forest (POP), Pinus tabulaeformis Carr. pure forest (PTP), Platycladus orientalis–Pinus tabulaeformis mixed forest (PPM), Platycladus orientalis coniferous and broadleaved mixed forest (POCB), Pinus tabulaeformis coniferous and broadleaved mixed forest (PTCB), deciduous broadleaved mixed forest (DBMF), and one area of non-afforested land (NF), with similar stand conditions were selected and fourteen factors of soil physical and chemical characteristics were measured and used to establish a total data set (TDS), while a minimum data set (MDS) was obtained by using the principal component analysis (PCA) and Pearson correlation analysis methods. Two scoring methods, linear (L) and non-linear (NL), were used to calculate the soil quality index (SQI), and the key factors influencing soil quality by vegetation were identified by a general linear model (GLM), PCA, and correlation analysis. The results showed that: (1) The screened MDS indicators which showed good relationships with the SQIs in the study areas were total nitrogen (TN), sand content, total potassium (TK), pH, and available water capacity (AWC). The SQI–NLM method has better applicability. (2) The contribution rates of vegetation to different soil factors accounted for 28.644% (TN), 21.398% (sand content), 24.551% (TK), 16.075% (pH), and 9.332% (AWC). (3) TN showed a positive relationship with all vegetation types; the content of TN in PTCB and DBMF was obviously larger than in the other types in the 0–10 cm layer; PPM, PTCB, and POCB affected the sand content, which showed negative correlativity; and DBMF showed positive correlativity with AWC. The mechanism of how different species affect TN, sand content, and AWC should be focused on and taken into consideration in further studies.

Analisis Kualitas Air Dan Daya Tampung Beban Pencemaran Sungai Bedadung

The purpose of this research article is to find out the water quality and capacity to carry pollution loads in the Bedadung River. The quality of river water in an area is greatly influenced by human activities. Therefore, it must be balanced with public awareness in preserving the river environment so that the quality of river water is maintained. Water quality is the general condition of water that describes the chemical, physical and biological content of water with the help of certain references. Water quality is usually influenced by the pollutant load entering the water body. The pollutant load itself is the amount of pollutant substances present in the water. In a body of water there is a limit to the amount of pollutant load that can be accepted by its designated class or what is generally referred to as the maximum pollutant load.

Water holding characteristics of litters of typical forest in loess area of Western Shanxi Province, China

It is of great significance to investigate the volume and water holding characteristics of litters for the accurate evaluation of forest water conservation function. With Pinus tabuliformis, Robinia pseudoacacia, Populus davidiana, Quercus wutaishanica and Platycladus orientalis as the research objects in the Loess Plateau of Western Shanxi Province, we analyzed the thickness of undecomposed layer and semi-decomposed layer, the volume of litter, and the relationship between the litter water-holding characteristics and the immersion time for different stands by the combination of sample survey and indoor immersion test. The results showed that the total thickness of litter layer was 4.06-5.12 cm, with the thickest layer in R. pseudoacacia forest and the thinnest in P. tabuliformis forest. The storage volume of litter was the largest in Q. wutaishanica (24.39 t·hm-2), followed by P. davidiana (23.64 t·hm-2), P. orientalis (22.51 t·hm-2), and R. pseudoacacia (22.48 t·hm-2), and the smallest in P. tabuliformis (20.42 t·hm-2). The volume in the undecomposed layer was less than that in the semi-decomposed layer. The maximum water holding of litter was 40.41-79.56 t·hm-2, with the highest of Q. wutaishanica and the lowest of P. tabuliformis. The effective interception rate of litter was 108%-188%. The changes of water capacity and water absorption rate of litter were most rapid in Q. wutaishanica, P. davidiana and R. pseudoacacia, and the changes were faster in the semi-decomposed layer than in the undecomposed layer. The water-holding capacity of litter in five forests was following an order of Q. wutaishanica>P. davidiana>R. pseudoacacia>P. orientalis>P. tabuliformis.

Evaluation Of Drainage Canal Mitigation In Banjarmasin City Post Hydrometeorological Disaster

Data from the Environmental Health Risk Assessment (EHRA) study in 2012 stated that 52% of inundation in Banjarmasin City was caused by a problematic drainage system, the causes of which included siltation of the canals and the large number of weeds growing around the drainage canals, which would interfere with the function of the drainage canals. The data used are road canal cross-sectional dimensions, topographical data, canal alignment data, and land use data in North Banjarmasin Sub District. The calculation analysis method uses the Mononobe method. The results of these calculations will later be used for modeling which are indicated to exceed the water capacity, of course also by adding topographical parameters, land use, and canal alignment. Meanwhile, the planned discharge data from the results of the calculated rainfall and the measuring data of the channel cross-sectional dimensions are used for detailed modeling of the channel cross-section using HecRas. The condition of drainage channels is over-capacity, influenced by the presence of several channels covered with bushes and concrete, the amount of sediment that has not been dredged, the absence of an adequate catchment area system due to the characteristics of the soil in the form of peat soil.

ANALISIS JARINGAN PIPA DISTRIBUSI AIR BERSIH DI DESA SRIMULYO KECAMATAN AIR SALEK KABUPATEN BANYUASIN

Srimulyo Village, Air Salek District has a water connection with PDAM Tirta Betuah as a clean water service provider. The problem that occurs is the lack of water pressure, so it cannot meet the need for clean water for 24 hours. Apart from loss of head, it is projected that there will be changes in population which will increase the burden on clean water capacity at the research location. This research was conducted to determine the existing clean water needs, population projections, and determine head loss. This calculation uses geometric methods to calculate population projections, as well as the Hardy Cross method to calculate pressure loss. In the drainage area in Srimulyo Village, the total need for clean water in 2022 is 371,760 lt/day, the projected population for the next 5 years in 2027 is 5,164 people, and in the next 10 years 2032 it is 6,435 people. And the loss of pressure height occurred in block 3, namely 6.03 m and the remaining pressure was 33.34 m. This is caused by a change in pipe diameter from 6 inches to 4 inches.

Can agronomic options alleviate the risk of compound drought-heat events during the wheat flowering period in southeastern Australia?

The impacts of compound drought-heat (DH) events on crops are more devastating than a single extreme event of drought or heat. Previous studies mainly assessed the change of individual extreme climate events. However, studies quantifying the characteristics of DH events during crop growth periods are still lacking. To the best of our knowledge, there is no study that has quantified the potential of adjusting sowing time and changing cultivars to reduce the risk of DH events for wheat in Australia. We aimed to (1) develop a combined index to capture the DH events occurring during the wheat flowering period at six study sites in southeastern Australia’s wheat belt; (2) quantify the changes in the frequency (DHF), duration (DHD), and intensity (DHI) of DH events under future climate; and (3) identify feasible agronomic options to reduce the risk of DH events. We used the APSIM model driven by climate projections from 27 GCMs for the period of 1981–2100 to simulate the wheat flowering time and daily plant available water (PAW) at 0–100 cm soil layer. The wheat sensitive period (WSP) was defined as the period from 2 weeks before flowering to 2 weeks after flowering time. A DH event occurs when the daily maximum temperature is higher than 28 ℃ and daily PAW is less than 40% of plant available water capacity for three consecutive days or more. Then, we assessed the DHF, DHD, and DHI under projected climate change. Finally, we investigated the potential of changing sowing time and cultivars to alleviate DHF, DHD, and DHI under different climate scenarios. According to the average values across six sites, the DHF, DHD, and DHI during the WSP increased by 15%, 12%, and 0.9% in 2040 s, and 49%, 44%, and 5% in 2080 s, respectively, compared to 2000 s. Such increases in DH events were mainly due to enhanced heat events. Early sowing and planting better-performing wheat cultivars with early flowering had great potential to lower the risk of future DH events. They could reduce the DHF, DHD, and DHI by 15%− 100%, 18%− 100%, and 16%− 100%, respectively, compared to without adaptation options. However, the strategy may introduce an increased frost risk across six sites, especially in regions with climates that are less dry and hot, such as Mudgee and Wagga Wagga. We expect our modelling work can provide useful information for developing effective agronomic management practices to help Australian wheat growers better prepare for DH events under climate change. The newly proposed DH framework can be applied to other dryland wheat growing regions globally.

Crop rotations influence soil hydraulic and physical quality under no-till on the Canadian prairies

Cropping system sustainability is dependent on the conservation of soil hydraulic and physical quality over time. This study examined the effects of crop rotations on soil hydraulic and physical quality on the Canadian prairies, emphasizing choices of crop species and sequence to preserve or improve soil quality under no-till management. Field experiments were initiated in spring 2018 at three sites: Lethbridge (Alberta), and Swift Current and Scott (Saskatchewan) to evaluate six crop rotations, consisting of (i) conventional (control), (ii) pulse/oilseed intensified, (iii) diversified, (iv) market-driven, (v) high-risk and high-reward, and (vi) soil health-enhanced. Undisturbed soil cores were collected from 5–10 and 15–20 cm soil depth increments in 2021 after crop harvest, to determine bulk density (BD), total (TP) and effective porosity (EP), pore size distribution, soil water retention, and unsaturated hydraulic conductivity. Results revealed that crop rotations did not significantly impact BD, TP, or EP in the 5–10 and 15–20 cm soil depth increments across the three sites. Depending on the site and soil layer, the pulse/oilseed intensified, diversified, high-risk and high-reward, and soil health-enhanced rotations improved macroporosity by 13−127% and mesoporosity by 1−36% compared to the conventional rotation, resulting in concomitant increases in large and medium unsaturated hydraulic conductivities. At Lethbridge, both conventional and high-risk and high-reward rotations resulted in increased water content at field capacity (FC) by 12–14%, permanent wilting point (PWP) by 7−12%, and plant available water capacity (PAWC) by 16−17%, accompanied by significant increases in microporosity (8%) and residual porosity (16%) in the 5−10 cm depth compared to the soil health-enhanced rotation. However, no significant differences were found at Swift Current or Scott in the 5−10 cm depth. The pulse/oilseed intensified rotation significantly improved FC by 22% and PAWC by 19% compared to the market-driven rotation. This rotation also showed an 18% increase in FC and a 32% increase in PWP when compared to the diversified rotation at Scott in the 15−20 cm depth, but did not differ significantly at Lethbridge or Swift Current. Overall, crop rotations with legumes and increased functional diversity have the potential to improve soil physical quality and plant available water but may require a period longer than the present study’s duration to become evident.

Influence of intensive cropping of vegetables on physical and hydraulic properties and functions of an Oxisol in the Brazilian Cerrado

The intensification of agricultural systems (e.g., vegetable production) to supply the food demand of the world’s population has increased over the last decades. In Brazil, the largest area of vegetable cropping systems is located in the Oxisols within the Cerrado biome. These areas are characterized by intensive land use and large-scale mechanized agriculture, which may affect the soil physical quality over time. This study aims to understand the effects of vegetable cropping (VG) systems on physical-hydric properties of highly weathered Oxisols. To this end, soil physical properties were assessed in representative VG systems of different ages [15 (VG15), 20 (VG20), and 30 (VG30) years old] and in a native Cerrado vegetation (CV), which was used as a reference of an intact system. Several analyses were conducted, including soil water retention curve, soil bulk density (ρ), soil penetration resistance (PR), saturated hydraulic conductivity (Ksat), disaggregation index, and structural stability index. In addition, a soil physical quality index (SPQI) was developed to assess the effects of soil management on soil functions and ecosystem services in the VG systems evaluated. It was observed that VG systems promoted soil compaction as indicated by the increase in ρ and PR values compared to the CV. This resulted in changes in soil porosity with mesopores being the most affected. The changes in soil porosity reduced Ksat and field capacity, and increased the permanent wilting point, leading to a reduction in available water capacity. The SPQI was reduced by 34, 32, and 43% in VG15, VG20, and VG30, respectively, compared to the CV (0.89). Based on our SPQI, support of root development and resistance to erosion and degradation were the soil functions most affected, regardless of the VG system age. Our results indicate the need to improve the current management used in VG systems to mitigate soil compaction and improve soil physical quality of Oxisols under these systems in the Brazilian Cerrado. This is essential to restore soil functionality and to ensure the sustainable food production of these systems in the long term.

Effect of biochar aging in agricultural soil on its wetting properties and surface structure

Biochar wettability and ability to accumulate moisture inside the porous space are crucial for improving soil fertility, regulating soil water balance, and regulating nutrients. However, a long-term interaction of biochar with agricultural soils may drastically alter the wetting properties and, eventually, influence water holding capacity and the structure of soils. In this work, the structure and wetting properties of biochar samples after 6-year long exposure to a sandy loam Spodosol with a crop rotation and mineral fertilizers application were studied. It was found that the elemental composition of the aged biochars was richer and more "soil-like", which is explained by the presence of the mineral crust on the biochar surface. The temporal evolution of biochar in the soil without any mineral fertilizer application resulted in significant improvement of its surface wettability due to the effects of various environmental factors. The lateral surface of biochar after 6-year interaction with the soil changes into a loose porous layer in a form of grooved base filled with adherent mineral soil and clay particles. Contrary, the application of the mineral fertilizer to the soil resulted in decreased wettability of the biochar lateral surfaces due to a decrease in the polar component of surface energy and the crusting of the surface with fine material, which blocks the pore space of the biochar. As a result, water capacity of the biochar from the treatment with the fertilizer decreased compared to the biochar samples collected from the soil without the fertilizer application. The radial biochar surfaces of both types of samples collected from the soil were open vessels filled with soil particles that slow down complete wetting and water absorption. The treatment of the biochar samples with surfactants drastically increased wettability of lateral surface and water absorption capacity of control samples as compared to the samples collected from the soil. The obtained results support the idea that the hydrophilisation of biochar caused by the adhesion of soil particles and treatment of its pore surface with surfactants, can improve the water-holding capacity of the sandy loam Spodosol in the plant-available range of soil water.Graphical

Hydraulic and pore functions of differently textured soils modified by biochar from different parts of the mango plant

Studies that elucidate the likely differential impact of biochar produced from different parts of the same plant on soil functions and structure are scanty. Therefore, in this study, biochar made from 2 feedstocks: Mango Twig (B1) and Mango Branch (B2) were pyrolyzed at 550 ○C, and mixed with 2 differently textured substrates (silt loam – S and sandy loam –SD) at application rates of 0%, 3%, 4.5% and 6%, and uniformly prepared to a bulk density (BD) of 1.4 g cm−3. The substrates were subsequently subjected to standard procedures to characterize the affected water retention properties, air permeability, and saturated hydraulic conductivity (Ks). The results indicate marked differences in the impact of biochar types on the available water and water retention capacity, depending on soil texture. The significant main effect of the biochar type on Ks in silty loam and the plant available water capacity in sandy loam highlights the relevance of the selected part of the feedstock pyrolyzed. The optimum amount of biochar required to achieve a significant increase in soil water content was about 3% in both substrates, while air permeability and pore continuity were significantly altered at about 6% biochar amendment rate. Moreover, significant (P < 0.05) improvements in the saturated hydraulic conductivity were observed in the biochar-amended soil compared to the control. Air permeability decreased as the added biochar increased, while the air-filled pores increased at defined matric potential in all treatments. The improvement in soil functions was mostly due to the modification of soil structure parameters (pore size distribution (PSD) and pore continuity), due to increased meso pores concomitant with biochar additions; and greater changes were obtained with B1. The varied impact of the biochar types especially on the soil water retention, available water capacity, pore continuity, and hydraulic properties for the different soil textures showed that even the selected plant part affects the options to improve soil functions.

Vertical Changes of Organic Carbon Storage, Structural and Hydraulic Properties of a Humid Tropical Soil under Vegetation Cover in Southeast Nigeria

Changes in organic carbon storage (OCS), structural and hydraulic properties with depth of soil are important phenomena that need to be understood per soil for effective soil management in crop production. A study was conducted in a Randomized Complete Block Design (RCBD) to assess the vertical changes in OCS, structural and hydraulic properties of soil under vegetation cover. The study involved 5 levels of sampling depth replicated nine (9) times to give forty five (45) observational units. The nine points for sampling were randomly selected and the five sampling depths were 0 – 20, 20 – 40, 40 – 60, 60 – 80 and 80 – 100 cm. Auger and core soil samples were collected at the designated depths. The samples were processed and analysed in the laboratory. The results of data analyses showed that depths varied significantly (P≤0.05) in the parameters measured. The highest OCS of 38.28 ton / ha was obtained at the 0 – 20 cm depth and the lowest (10.38 ton / ha) was obtained at 80 – 100 cm depth. The highest mean weight diameter of 1.00 mm and lowest of 0.72 mm were obtained at 0 – 20 and 80 – 100 cm depths, respectively. The lowest clay dispersion index of 25.43 % and the highest clay flocculation index of 74.53 % were obtained at 80 – 100 cm depth. Clay content and bulk density (BD) increased with depth and, the highest clay content of 212.4 g / kg and highest BD of 1.65 mg / m3 were obtained at the 80 – 100 cm depth. Saturated hydraulic conductivity (Ksat), total porosity (Pt) and macroporosity (Pm) decreased with depth. The highest Ksat of 3.11 cm / hr, Pt of 47.41 % and Pm of 24.13 % were obtained at 0 – 20 cm depth. The water retention characteristics increased with depth. The highest field capacity of 24.46 %, permanent wilting point of 11.16 % and available water capacity of 13.32 % were obtained at 80 – 100 cm depth. There were consistent changes in the soil properties across the depths. The reduced drainage at the higher depths should be considered in cultivating deep rooted crops which are sensitive to poor drainage. The top soils should be managed with good agronomic practices and minimum tillage to avert damages to the microaggregates.

Vertical Shaft Kinetic Turbine Performance Using A Cup-Shape Blade

The abundant availability of alternative energy sources forms the fundamental foundation for rural energy development. In particular, renewable energy sources are indispensable in rural areas due to their eco-friendly nature and widespread accessibility, which helps preserve the environment by avoiding pollution. Indonesia, a country blessed with vast water resources, especially its rivers, holds enormous potential for harnessing kinetic energy derived from fast-flowing river waters. Effective utilization of this kinetic energy has the potential to address energy shortages in the country. In this context, there is a pressing need to enhance the efficiency of kinetic turbines designed to function as electricity generators in rural regions. This study focuses on evaluating the impact of variables such as the guide angle, water flow speed, and turbine rotation on turbine power and efficiency. The study employs an experimental approach to achieve its objectives, involving tests to assess the performance of a vertical shaft kinetic turbine equipped with bowl blades. Data analysis based on the experimental findings enables the determination of both turbine power and efficiency. The study outcomes demonstrate that the bowl blade type turbine outperforms the curved blade type, primarily due to its larger water capacity, which significantly exceeds that of the curved blade variant. This study emphasizes the potential for harnessing kinetic energy efficiently in rural areas to support sustainable energy development.