Soil Moisture Retention Characteristics Of Saprock From The Weathering Profile Over A Biotite-Muscovite Granite In Peninsular Malaysia

The weathering profile at the slope cut near Km 16 of the Kuala Lumpur - Ipoh trunk road can be differentiated into an upper, 11.8 m thick pedological soil (zone I) and a lower, 31.9 m thick saprock (zone II) comprising silty sandy gravels that distinctly preserve the minerals, textures and structures of the original granite. In order to investigate the influence of particle size distributions on soil moisture retention characteristics, saprock samples were collected at depths of 26.53 m (Sample A), 31.29 m (Sample B) and 41.93 m (Sample C). Samples A and B, with porosities of 37%, comprise 33% gravel, 27% sand, 22% silt and 18% clay, and 31% gravel, 24% sand, 25% silt and 22% clay, respectively. Sample C with a porosity of 44% consists of 24% gravel, 28% sand, 38% silt and 10% clay. Tests with the pressure plate method show increasing suctions from 0 kPa through 0.98 kPa and 9.8 kPa to 33 kPa and 1,500 kPa to result in gravimetric soil moisture retentions of 31.9% through 28.6% and 23.3% to 16.9% and 6.8% in sample A, of 32.1% through 24.9% and 21.5% to 17.8% and 7.4% in sample B, and of 31.5% through 30.3% and 27.30% to 23.5% and 9.5% in sample C. Regression analyses of gravel, sand and clay contents plotted against moisture contents retained at high suctions (33 kPa and 1,500 kPa) yield negative trends with variable correlation coefficients (R2), though plots involving silt contents yield positive trends with large correlation coefficients (R2 >0.9966). It is concluded that adsorption of water on surfaces of silt sized particles (of mainly sericite derived from weathering of feldspars) that gives rise to the retention of soil moisture in saprock.

Comparison of six zero-till seed drill openers for establishment and persistence of sod-seeded alfalfa (Medicago sativa L.) in a cool-season perennial grass pasture

Zero-till seed drills are readily available for crop seeding in the prairie region of western Canada but have not been evaluated for sod-seeding in perennial forage. Sod-seeding a legume, such as alfalfa (Medicago sativa L.), into the existing perennial grass vegetation improves forage yield and quality for ruminant livestock grazing and production. Suppression of the existing vegetation with herbicide has been reported to increase alfalfa seedling establishment. We evaluated six commercially available zero-till seed drill openers by sod-seeding alfalfa into a crested wheatgrass [Agropyron cristatum (L.) Gaertn.] pasture with or without glyphosate suppression of the existing vegetation in Lanigan Saskatchewan. Alfalfa seedling establishment (52.2 vs. 21.9 seedlings m−1 ± 6.8), alfalfa composition (42.5% vs. 0.2% ± 8.6), and alfalfa yield (1105 kg·ha−1 vs. 12 kg·ha−1 ± 206) in 2011 were increased by the application of herbicide. Seed drill openers performed similarly for all three variables. Nine years later, in June 2020, there was greater alfalfa composition (13.3% vs. 0% ± 2.3) and forage yield (1325 vs. 957 kg·ha−1 ± 127) in the sod-seeded plots than in the unseeded controls but the alfalfa plant cover, alfalfa composition, alfalfa yield and forage yield were similar among seed drill openers. There was also no difference in these variables due to herbicide application nine years prior. Livestock producers can utilize currently available zero-till seeding equipment for sod-seeding alfalfa to rejuvenate grass pastures in the thin Black soil zone of western Canada with the expectation of persistence of alfalfa for nine years.

Characterizing a weathering profile over the Kuantan Basalt

Three broad morphological zones can be differentiated; the top pedological soil (Zone I) being 3.60 m thick and comprising brown, soft to stiff, clays. The intermediate saprock (Zone II) is 1.12 m thick and consists of brown, very stiff, sandy silt with many lateritic concretions, whilst the bottom bedrock (Zone III) is an outcrop of vesicular olivine basalt with weathering along joints. Constant volume samples show the saprolite (sub-zone IC) to have dry unit weights of 11.78 to 12.80 kN/m3, whilst the solum (sub-zones IA and IB), and saprock, have values ranging from 10.65 to 11.09, and from 11.35 to 11.50, kN/m3, respectively. Porosities are variable; the saprolite with the lowest values of 52 to 56% and the solum and saprock with values of 57 to 60%. Clay and silt contents increase up the profile with a corresponding decrease in sand and gravel contents. Colloid (<1 μm size) contents especially increase up the profile from 10 to 15% in saprock through 30 to 40% in saprolite and exceeding 57% in the solum, These increasing colloid contents point to the increasing effects of pedological processes. Thin-sections of weathered rims (1-2 cm thick) show alteration of basalt to start with formation of micro-cracks (Stage 1) that become stained by secondary iron oxides and hydroxides. Decomposition of the essential minerals then occurs in the order: olivine (Stage 2), augite (Stage 3), and plagioclase feldspar (Stage 4). An increase in apparent porosity, but a decrease in unit weights and specific gravity, reflect these stages of weathering; the boundary between ‘rock’ and ‘soil’ material occurring when all olivine and augite crystals have decomposed. It is concluded that the weathering profile results from in situ alteration of basalt due to lowering of an unconfined groundwater table; pedological processes giving rise to further alteration.

Evaluation of the use of the Microwave system and Calculation of Economic Efficiency

Cost-effectiveness calculations for computational irrigation options, costs of sugar beet productivity by macro and microelements, costs associated with the assembly of single added microsurgeons, cost of microwave system, expenditure on production of products according to options, etc. the experimental results of the experimental studies carried out in different regions of the country are proven by the fact that the use of microcirculation by drop irrigation method is well-aerated in the soil zone in the soil zone of the root system of plants, where normal biological activity of beneficial microorganisms is provided, it is ensured that the required amount of continuous fertilizer in the formulation of the solution provides optimal nutrient, water and air regimes in the soil, which in turn promotes biological and physical improvement of the plant and, consequently, increases productivity and improves product quality

Triterpenoid and Steroidal Saponins Differentially Influence Soil Bacterial Genera

Plant specialized metabolites (PSMs) are secreted into the rhizosphere, i.e., the soil zone surrounding the roots of plants. They are often involved in root-associated microbiome assembly, but the association between PSMs and microbiota is not well characterized. Saponins are a group of PSMs widely distributed in angiosperms. In this study, we compared the bacterial communities in field soils treated with the pure compounds of four different saponins. All saponin treatments decreased bacterial α-diversity and caused significant differences in β-diversity when compared with the control. The bacterial taxa depleted by saponin treatments were higher than the ones enriched; two families, Burkholderiaceae and Methylophilaceae, were enriched, while eighteen families were depleted with all saponin treatments. Sphingomonadaceae, which is abundant in the rhizosphere of saponin-producing plants (tomato and soybean), was enriched in soil treated with α-solanine, dioscin, and soyasaponins. α-Solanine and dioscin had a steroid-type aglycone that was found to specifically enrich Geobacteraceae, Lachnospiraceae, and Moraxellaceae, while soyasaponins and glycyrrhizin with an oleanane-type aglycone did not specifically enrich any of the bacterial families. At the bacterial genus level, the steroidal-type and oleanane-type saponins differentially influenced the soil bacterial taxa. Together, these results indicate that there is a relationship between the identities of saponins and their effects on soil bacterial communities.

Influence of Particle Shape on the Macroscopic and Mesolevel Mechanical Properties of Slip Zone Soil Based on 3D Scanning and 3D DEM

The macroscopic and mesolevel mechanical mechanisms of slip zone soil are a crucial subject for the research of landslide deformation evolution and slope control, but the effects of the shape and psephicity of coarse particles in a slip zone soil on the mechanical properties of the slip soil zone still need to be explored. Discrete element method (DEM) can effectively monitor and track the mesolevel mechanical parameters of geotechnical materials, such as displacement vector field, contact force chain, and particle coordination number. The rock blocks in the medium-sized shear test undergo a sophisticated process by 3D scanning technology, and a database of the blocks is established and accurately modeled by combining 3D DEM to simulate the indoor medium-sized shear test for numerical investigation in line with the test conditions. The numerical simulation results demonstrate that the psephicity and particle shape of the rock blocks significantly affect the dilatancy and mesolevel mechanical parameters of the slip zone soil specimens. In addition, the numerical models featured by poorer psephicity and more irregular particle shape display more evident dilatancy, larger particle coordination numbers, as well as better contact density inside the model. Some references for the study of the macroscopic and mesolevel mechanical mechanisms of slip zone soil are provided.

PSXI-15 Evaluation of low-lignin alfalfa ‘Hi-Gest® 360’ on the Canadian prairies: productivity, nutrient profile, and rumen degradation kinetics

The study was conducted at Saskatoon, SK, Canada in the Dark Brown soil zone (52°07′N,106°38′W), to compare low-lignin Hi-Gest®360 alfalfa (Hi-Gest; Medicago sativa L.) to a conventional alfalfa (AC Grazeland) under two cutting regimes. Each cultivar was seeded in 2017 as both a monoculture and binary mixture (binary; Hi-Gest+HB and Grazeland+HB) with AC Success hybrid bromegrass (HB). Plot size was 1.2m×6m with 4 rows. Three years (2018–2020) result suggested that the first cut DMY was 1695±241 and 2151±276 kg/ha for the Hi-Gest and Grazeland, respectively. Hi-Gest had greater (P &lt; 0.05) TDN (68.4 vs. 66.6%, DM basis), NEm (1.7 vs. 1.6 Mcal/kg), IVNDFD48: (42.9 vs. 37.8%), but lower second cut DMY (1288 vs. 1560 kg/ha), ADF (26.3 vs. 28.7%), NDF (34.7 vs. 36.6%), compared to AC Grazeland. Under two cutting, Hi-Gest was numerically lower in total DMY (2983 vs. 3712 kg/ha; P = 0.114) relative to Grazeland. In first cut forage, Hi-Gest also was numerically lower in ADL (5.9 vs. 6.5%; P = 0.57) relative to AC Grazeland. Hi-Gest was similar (P = 0.15) with AC Grazeland in effectively degradable dry matter (EDDM; 622 g/kg DM), effectively degradable CP (EDCP; 689 g/kg CP). Hi-Gest alfalfa had greater (P = 0.05) effectively degradable neutral detergent fiber (EDNDF; 19% more; 340 vs. 285 g/kg NDF) relative to AC Grazeland alfalfa. In binary system, Hi-Gest+HB had (P = 0.02) greater EDCP (12% more; 526 vs. 468 g/kg CP), and numerically greater EDNDF (4.4% more; 259 vs. 248 g/kg NDF; P = 0.10) but had similar EDDM (409 g/kg DM) relative to Grazeland+HB mixture. Each percentage unit increase in alfalfa ADL concentration decreased EDNDF by 2.3 percentage units (EDNDF, % NDF = 46.0–2.93×ADL, % DM, r2=0.26, P &lt; 0.01). Although Hi-Gest yielded less (~25% less) than AC Grazeland, Hi-Gest had greater nutritive value compared to AC Grazeland; differed little for yield and quality in binary mixture, suggesting Hi-Gest can be a viable alternative legume for western Canadian prairies.

THE PROBLEM SCIENTIFIC AND RESEARCH LABORATORY OF GEOGRAPHY AND SOIL CONSERVATION OF THE BLACK SOIL ZONE OF ODESSA NATIONAL UNIVERSITY (PSCL‑4 ONU) CELEBRATES50TH ANNIVERSARY!

Problem Statement and Purpose. The problem scientific and research laboratory of geography and soil conservation of the black soil zone (PSCL‑4 ONU) was opened at the Geology and Geography Faculty of Odessa University half a century ago, in 1971. The main task of the research laboratory resided in conducting soil researches in the steppe zone of the south of Ukraine in connection with the commencement of irrigation programs there, soil and land mapping to streamline their use. The aimof this article is to highlight the major milestones of the half-century history of the research laboratory, as well as outline achievements and research activities during this period.Data & Methods. Documents and materials on the history of formation and development of the PSCL‑4, documents and materials on the research activitiesduring 50 years, as well as the other author’s publications from the previous years. To highlight the half-century history of the PSCL a classic geographical and historical-and-research approaches has been applied, which combines the principlesof historical and analytical assessment of both: historical milestones and obtained achievements.Results. Starting from 1971 the soil sciences expedition of the PSCL4 conducted a large-scale(1:10000 and 1:25000) survey and mapping of soils of collective and state farms in the south of Ukraine, Russian Federation, North and Central Kazakhstanin the area of more than 6 mln. ha. PSCL4 staff has been studying the impact of waters of different irrigational quality on the chemical composition of the southern Ukrainian soils, as well as properties and productivity of these soils. There has beenestablished genetic nature and negative direction of a number of processes in the black soil under irrigation, there also have been justified and introduced into practice different measures to protect and increase fertility of soils under irrigation and drainage. In 2003 there have been commenced research and mapping of soils and soil cover on Zmiiny island. The studies of modern landscapes and soil-geochemical environments and processes on the estuary coasts in the Northwestern part of theBlack Sea region as well as city`s soil, are considered additionally in the research within recent years. Bearing in mind problems and topics the PSCL4 addressed during its long-term scientific and research activities there has been developed ascientific school – “Soil Formation Processes in Black Soils of the Steppe Zone.” Over half a century the department schooled 14 candidates and 3 doctors of sciences, published more books, scientific articles, scientific and practical recommendations, and training manuals.

Saturated hydraulic conductivity (Ks) of earth materials in a weathering profile over the Kuantan Basalt, Pahang, Malaysia

Three broad morphological zones can be differentiated at the weathering profile; the top, 3.80 m thick, pedological soil (zone I with sub-zones IA, IB and IC) comprising soft to stiff, brown clays and the bottom bedrock (zone III) being an outcrop of vesicular olivine basalt. The intermediate zone II (saprock) is 1.12 m thick and consists of brown, very stiff, sandy clayey silt with many lateritic concretions. Laboratory constant head permeability tests show the saturated hydraulic conductivity (Ks) to vary with depth; sub-zone IB having a conductivity of 0.007 cm/hr, and sub-zone IC (saprolite), and zone II (saprock), having conductivities of 0.147, and 0.447, cm/hr, respectively. The conductivity values show no correlation with physical properties of the earth materials, but increase with increasing sand, gravel, and silt, contents. The conductivity values also decrease with increasing clay and colloid contents. The low hydraulic conductivity of sub-zone IB will lead to surface runoff and ponding over natural ground surfaces during rainfall events, though over disturbed ground surfaces, infiltration is anticipated in view of exposed saprolite and saprock earth materials with relatively high conductivity