Wood ash as a vegetative-growth promoter in soils with subsurface compaction

ABSTRACT Subsurface soil compaction and nutritional stress are among the main factors that limit the yield of crops. Using forest residues, such as wood ash, is a viable option in the chemical recovery of soils and can promote vigorous root development in soils with subsurface compaction. The objective of this study was to indicate the most adequate dose of wood ash for efficient management of this residue applied in rotational crops cultivated in soils with subsurface compaction. Safflower plants (Carthamus tinctorius), a rotational crop with a deep taproot system, were grown in clay soil fertilized with different doses of ash and with induced levels of compaction in the subsurface layer. The experiment was conducted in a randomized block design, under a 4 × 5 factorial scheme, composed of four doses of wood ash (8.0, 16.0, 24.0, and 32.0 g dm-3) and five levels of soil bulk density (1.0, 1.2, 1.4, 1.6, and 1.8 kg dm-3), with four replicates. Crop growth variables (plant height, number of leaves, stem diameter, and SPAD chlorophyll index) were evaluated at 15, 45, and 75 days after emergence. The results indicated that soil compaction was the most limiting factor to the vegetative development of safflower, regardless of the ash dose. The interaction between the wood ash dose and bulk density, when present, showed that the best growth response occurred for ash dose of 25 g dm-3 for a soil bulk density of 1.2 kg dm-3.

Characteristics of product complementary feeding with fortified fish protein hydrolysate (FPH)

Malnutrition is still a major problem in Indonesia, particularly stunting and acute malnutrition due to protein deficiency. In contrast, Indonesia is rich in protein sources such as fish but they are poorly utilized. Biologically processed fish protein hydrolysate (FPH) has proven to be highly nutritious and digestible. Our preliminary study in developing the High Protein Complementary Food (HPCF) formula for infant enriched with FPH, showed that of 17 formulas, 3 formulas was the best. This study was aimed to analyzing sensory analysis using the hedonic test, physical analysis and absorption protein. The result shows that the hedonic test of FPH-enriched HPCF infant food revealed that the product was acceptable in term of colour, aroma and texture. In comparison to the commercial product, FPH-enriched instant HPCF infant product had higher bulk density. The highest Water Absorption Index (WAI) was F1-C, the highest Water Solubility Index (WSI) was F1-P, and the lowest rehydration was F2-P. Compared to commercial products, the instant FPH-enriched HPCF baby porridge has a bulk density that is greater than that of commercial products. The highest Water Absorption Index (WAI) was F1-C, the highest Water Solubility Index (WSI) was F1-P and the lowest time for Rehydration was at F2-P. HPCF enriched with FPH showed the best protein absorption significantly in the P2 treatment group

Utilization of Waste Glass in Autoclaved Silica–Lime Materials

This paper aims to investigate the possibility of using waste glass of different colours as a complete substitute for quartz sand in autoclaved silica–lime samples. On the one hand, this increases the possibility of recycling waste glass; on the other hand, it allows obtaining autoclaved materials with better properties. In this research, reference samples with quartz sand (R) and white (WG), brown (BG), and green (GG) waste container glass were made. Parameters such as compressive strength, bulk density, and water absorption were examined on all samples. The samples were examined using a scanning electron microscope with an energy dispersive spectroscopy detector (SEM/EDS) and subjected to X-ray diffraction (XRD) analysis. The WG samples showed 187% higher compressive strength, BG by 159%, and GG by 134% compared to sample R. In comparison to the reference sample, volumetric density was 16.8% lower for sample WG, 13.2% lower for BG, and 7.1% lower for GG. Water absorption increased as bulk density decreased. The WG sample achieved the highest water absorption value, 15.84%. An X-ray diffraction analysis confirmed the presence of calcite, portlandite, and tobermorite phases. Depending on the silica aggregate used, there were differences in phase composition linked to compressive strength. Hydrated calcium silicates with varying crystallisation degrees were visible in the microstructure image.

Soil Compaction after Increasing the Number of Wheeled Tractors Passes on Forest Soils in West Carpathians

Soil disturbance and compaction are inherent in ground-based harvesting operations. These changes are affected by numerous factors, related mainly to the technical parameters of the machines, soil conditions, and the technology used. This study aimed to analyze the changes of surface layers of soil caused by skidder traffic without loads on the Cambisols of Western Carpathians. We observed changes in the soil bulk density and penetration resistance. The results showed that only machine traffic caused a 0.32 to 0.35 (g cm−3) increase in soil bulk density. Besides machine traffic, bulk density was affected by soil moisture content. Penetration resistance of soil increased by 0.15 to 1.04 (MPa) after traffic of 40 machines. Penetration resistance showed a lower increase after traffic, and regression and correlation analysis proved a relationship between penetration resistance, skeleton content, and penetration depth, besides the number of machine passes (r = 0.33–0.55). Observing the changes in the physical properties of soils caused by machine traffic allows for a more detailed view of the effects of forest harvesting machinery on forest soils.

Sensitivity of Functional Traits to Environmental factors in a Karst Plant Community

In this study, the plant communities at five succession stages (herbage, herbage-shrub, shrub, tree-shrub, and tree) in the Zhenning Karst Plateau area of Guizhou were examined. The changes of plant functional characteristics in different succession stages were analyzed, as was the relationship between functional traits and environmental factors. The main results include the following. (1) During the succes-sion process, plant height, leaf dry matter mass, leaf area, leaf nitrogen content, and leaf phosphorus content gradually increased, whereas leaf thickness and specific leaf area decreased, and leaf C:P ratio and leaf N:P ratios did not change significantly. (2) Soil organic matter, soil total nitrogen, soil total phosphorus, soil C:N, soil C:P, and soil C:K increased at first and then decreased, reaching a peak at the tree-shrub stage. Soil total potassium fluctuated and soil bulk density gradually decreased and reached the lowest value at the tree-shrub stage. (3) Redundancy analysis (RDA) showed that the plant community shifted from a nutri-ent-poor soil environment to a nutrient-rich environment. Soil total phosphorus, soil C:K, soil organic mat-ter, soil C:N, and soil bulk density were the key environmental factors affecting the change of functional traits. (4) Structural equation modeling suggests that that specific leaf area and leaf nitrogen content had more sensitive responses to soil nutrient resources and environmental factors, respectively.

Fortification of cassava starch with coconut residue: effects on flours’ functional properties and products’ (Tapioca meals) nutritional and sensory qualities

Consumers are show interest in plant-based by-products due to their potential health-promoting properties. Coconut residue is food waste from coconut milk that is potentially rich in bioactive compounds, protein and dietary fibre. The effects of substituting cassava starch with coconut residue on the functional properties (bulk density, water absorption and swelling indexes), proximate composition, the energy value of flour, and sensory characteristics of tapioca grit's meal were studied. Cassava starch was mixed with coconut residue powder in five formulations that had 0, 10, 20, 30, and 40% of coconut residue powder, before being made into tapioca grits. The results showed that the bulk density, water absorption and swelling indexes decreased, whilst protein increased with the increasing addition of coconut residue. The colour of tapioca meals did not have any pronounced change in colour due to added coconut residue. Sensory results showed that tapioca samples fortified with 30% coconut residue was the most preferred with ranking in terms of aroma (8.7), overall acceptability (8.7) and willingness to buy (8.6) compared to other samples. Fortifying cassava starch with food waste like coconut residue improved the protein and fibre contents, and enhanced value addition and food product (tapioca meal) sensory quality.

Geological and soil engineering properties of shallow landslides occurring in the Kutupalong Rohingya Camp in Cox’s Bazar, Bangladesh

The Forcibly Displaced Myanmar Nationals (FDMN), historically known as ‘Rohingya’ who fled the 2017 ethnic atrocities and genocide in the Northern Rakhine State of Myanmar, took shelter in Cox’s Bazar District of Bangladesh. The camp network, known as Kutupalong Rohingya Camp (KRC), is situated in the tectonically active tertiary hilly terrain. The KRC has been experiencing hydrometeorological hazards, where landslides are frequent. This study investigated the slopes’ geological condition, engineering properties and human interventions, which influence the landslides. The exposed slopes were relatively high (> 10 m) and steep ranging from 40° to 60° that have numerous polygonal tension cracks and fissures. From the geological and geotechnical aspects, there are three successive units of slope materials: (1) residual soils of sandy silt with clay, (2) highly weathered silty sandstones and (3) shale/clay with silt and fine sand intercalations at the bottom of the slopes. Field observations revealed that most slope failures occurred in the residual soil and weathered silty sandstone units. The residual soils have a bulk density of 1.49–1.97 g/cm3, a liquid limit of 25–48%, a plasticity index of 5–16% and an undrained shear strength of 23–46 kPa. The silty sandstones have a bulk density of 1.44–1.94 g/cm3, an internal friction angle of 34°–40° and a cohesion of 0.5–13 kPa. The mineralogical composition determined by the X-ray diffraction shows low clay mineral content, which does not affect landslides. However, the slope geometry, low shear strength with strain softening properties and torrential rainfall accompanied by anthropogenic factors cause numerous landslides every year. This study will help take proper mitigation and preparedness measures for slope protection in the KRC area and surroundings.