Dependence of the content of microbial biomass in typical black soil on agrogenic factors and year season

The authors of the paper found that the nature and direction of the seasonal dynamics of the content of microbial biomass in typical black soil in grain-fallow crop rotation differ depending on the slope direction, the cultivation system and the soil layer. The characteristics of the dynamics of the content of microbial biomass in typical black soil in the agroecosystem of grain-fallow crop rotation, depending on the slope direction and the type of soil cultivation are revealed. The influence of the slope direction on the dynamics of the microbial biomass in the soil is more pronounced in the layer of 10-20 cm. The need to ensure the supply of a sufficient amount of post-harvest residues and organic fertilizers to the soil is shown. The increase in the uniformity of the upper layer of typical black soil is associated with the constant mechanical man-made impact on it. The obtained results about the nature of the impact of the studied factors on the seasonal and spatial variability of microbial biomass can be used in the development of systems for the management of the biological activity and reproduction of organic matter in black soils in order to improve their ecological state. The results of studies of the ecologically and agronomically important soil component i.e. microbial biomass are necessary for the development of systems for the regulation of soil fertility in order to increase their productivity, as well as for the development of a control system for the content of microbial biomass in black soils. The experimental data can serve as the basis for a database on the microbial pool of various soils and ecosystems, which is advisable to use for model predictive calculations, including in different ecological scenarios. The assessment of the state of organisms living in the soil and their biodiversity are important in the solution of the problems of environmental practice: identification of zones of ecological disadvantage, calculation of damage caused by man-made activities, determination of the stability of the ecosystem and the impact of certain anthropogenic factors.

Evaluation of carbonyl sulfide biosphere exchange in the Simple Biosphere Model (SiB4)

The uptake of carbonyl sulfide (COS) by terrestrial plants is linked to photosynthetic uptake of CO2 by a shared diffusion pathway. Applying COS as a photosynthesis tracer in models requires an accurate representation of biosphere COS fluxes, but these models have not been extensively evaluated against field observations of COS fluxes. In this paper, the COS flux as simulated by the Simple Biosphere Model, version 4 (SiB4) is updated with the latest mechanistic insights and evaluated with site observations from different biomes: one evergreen needleleaf forest, two deciduous broadleaf forests, three grasslands, and two crop fields spread over Europe and North America. To account for the effect of atmospheric COS mole fractions on COS biosphere uptake, we replaced the fixed COS mole fraction originally used in SiB4 with spatially and temporally varying COS mole fraction fields. The lower COS mole fractions in the late growing season reduces COS uptake rates in agreement with observations. We also replaced the empirical soil COS uptake model in SiB4 with a mechanistic model that represents both uptake and production of COS in soils, which improves the match with observations over agricultural fields and fertilized grassland soils. SiB4 was capable of simulating the diurnal and seasonal variation of COS fluxes in the boreal, temperate and Mediterranean region. The daytime vegetation COS flux is on average 8 ± 27 % underestimated, albeit with large variability across sites. On a global scale, our model modifications caused a drop in the COS biosphere sink from 922 Gg S yr−1 in the original SiB4 model to 753 Gg S yr−1 in the updated version. The largest drop in fluxes was driven by lower atmospheric COS mole fractions over regions with high productivity, which highlights the importance of accounting for variations in atmospheric COS mole fractions. The change to a different soil model, on the other hand, had a relatively small effect on the global biosphere COS sink. The small role of the modeled soil component in the COS budget supports the use of COS as a global photosynthesis tracer.

Investigation of Groundwater Potential Using Electromagnetic Method at a Basement Complex Area of University of Abuja, Gwagwalada

The Very Low Frequency Electromagnetic Method (VLF-EM) was used in view of detecting fractured or weathered zones within the University of Abuja Staff Quarters, Gwagwalada, Federal Capital Territory. The VLF -EM data measured along seventeen profiles of 400m at inter profile distance of 25m and interstation separation of 10m were done using the Scintrex ENVI Instrument. The VLF-EM survey revealed features significant to groundwater potential as conductive zones in the Fraser Filter maps and current density pseudosections. Three distinct zones were delineated based on the current density distribution. The fresh basement terrain corresponds to the highly resistive zone with current density value less than -20. The intermediate zone has current density value range of -20 to 25 typical of rocks and soil component which are slightly resistive to slightly conductive and corresponds to the partially saturated units. The third zone is highly conductive with current density value greater than 30 which includes the saturated weathered or fractured basement, fault zones, clay units and saturated sandy units within the study area. The north eastern, north western (profiles 1-8) and some parts of the southern region (profiles 16 and 17) of the study area show higher conductive zones than the central parts of the study area. This survey has helped in detecting sites that are suitable for groundwater exploration by identifying water bearing fractures and weathered zones in the study area. The areas with high conductivity response are areas with conductive overburden material such as clayey soil, saturated soil, water filled fractures and faults or weathered zone within the basement.

Habitat and edaphic preference of Rafflesia R. Br. plant communities in Royal Belum State Park, Perak, Peninsular Malaysia

Aim: To investigate the relationship between the microhabitat conditions and soil physico-chemical characters of Rafflesia plant communities and to determine similarities across Rafflesia habitats in Royal Belum State Park, Perak, Peninsular Malaysia. Methodology: The site of Rafflesia population and its microhabitat condition was collected by referring to the previous studies, in addition to interviewing the related parties. A plot study was constructed in each Rafflesia habitat in Royal Belum State Park, Perak and the soil sample was collected for estimating their characteristics. Results: Rafflesia population is distributed between 207 - 386 m asl, with the surface slope of 8 to 58° and located 1.0-450.0 m from nearby water sources. The percentage of clay has a strong influence in X-Ray and distance to water source affected the habitat in Sg. Ruok-Papan. Ca2+ was an important soil component in Sg. Kooi while in Sg. Gadong 2 and Sg. Selantan, nitrogen was the most important soil attribute. The dendrogram reveals Sg. Kooi and Sg. Gadong 1 were the most similar habitats while Sg. Ruok differed significantly in terms of the microhabitat and soil physicochemical conditions tested. Interpretation: This study shows that different plant communities favoured different conditions in terms of microhabitat condition and the physico-chemical characteristics of soil, despite being located within the same forest range. Since this study covered only small forest range, large sampling size which cover different forest area is needed to come to a conclusion regarding preference of Rafflesia plant communities towards its habitat.

Developing and testing a new quantitative near infrared spectroscopy online tracking measuring system for soil detection during automatic dishwashing

Near infrared (NIR) measurements have been used for several years to examine the processes taking place in the dishwasher during dishwashing. It is possible to differentiate between the soil components butterfat, oatmeal and egg-yolk and to determine their concentration in the dishwashing liquor quantitatively. Consequently, time-consuming dishwashing tests can be avoided by weighing the dishes. However, this method is also based on a small number of NIR measurements which are carried out intrusively during the dishwashing process, i.e. outside the dishwasher. These few NIR measurements make it difficult to investigate the dynamics of a dishwashing process. In this study, the development, testing and usage of a new online tracking measuring system is presented. The latter was used to perform 38 dishwashing processes, each containing 51 NIR spectra, to develop a calibration model using the partial least squares regression method with cross-validation. This new online tracking measuring system, based on the calibration, can determine the concentrations of three different soil components in the dishwashing liquor during automatic dishwashing. By recording the 51 spectra, it is possible to display a tracking curve for each soil component, i.e. the concentration courses of the dishwashing process over time. This results in a significantly better time resolution and it was possible to investigate the first dynamic part of the tracking curve, i.e. the beginning of the dishwashing process. This could lead to the opportunity to change the state of the dishwasher depending on the concentrations detected in the first step and, secondly, to a more environmentally friendly and cost-reducing dishwashing process.

Kajian Sebaran Humus, Alofan dan Senyawa Humus Kompleks Pada Tanah Andisol

Humic substances (humus), allophanes and humus complexes are the soil component which have highly reactivity and give great contribution on genesis and lead to presence of specific chemical and physical properties of Andisols. The study on humus, allophanes and humus complexes was conducted on Andisols in Tawangmangu Karanganyar District of Central Java and Bedugul, Tabanan District of Bali to observe the distribution of humus, allophanes and humus complexes along the profile and the factor affected its distribution. The result showed that the content of humus complexes tend to decrease with the dept in accordance to the content of humus, on the contrary of the content of allophanes. So the humus complexes are abundance on the upper layer whereas the allophanes on the lower layers of the profiles. By means of the regression calculation indicated that both of the pH (H2O) of the soil and the content of humus are controlled the formation of humus complexes and I or allophanes along the profiles.

A Review of Metal and Metal-Oxide Nanoparticle Coating Technologies to Inhibit Agglomeration and Increase Bioactivity for Agricultural Applications

Coatings offer a means to control nanoparticle (NP) size, regulate dissolution, and mitigate runoff when added to crops through soil. Simultaneously, coatings can enhance particle binding to plants and provide an additional source of nutrients, making them a valuable component to existing nanoparticle delivery systems. Here, the surface functionalization of metal and metal-oxide nanoparticles to inhibit aggregation and preserve smaller agglomerate sizes for enhanced transport to the rooting zone and improved uptake in plants is reviewed. Coatings are classified by type and by their efficacy to mitigate agglomeration in soils with variable pH, ionic concentration, and natural organic matter profiles. Varying degrees of success have been reported using a range of different polymers, biomolecules, and inorganic surface coatings. Advances in zwitterionic coatings show the best results for maintaining nanoparticle stability in solutions even under high salinity and temperature conditions, whereas coating by the soil component humic acid may show additional benefits such as promoting dissolution and enhancing bioavailability in soils. Pre-tuning of NP surface properties through exposure to select natural organic matter, microbial products, and other biopolymers may yield more cost-effective nonagglomerating metal/metal-oxide NPs for soil applications in agriculture.

Modelling phosphorus inflow to the Mozhayskoe reservoir with the HYPE hydrological model

Biogenic flow is the determining factor of ecological well-being of water bodies. It depends on a number of factors, such as weather conditions, soil and vegetation cover, agricultural use of the catchment area. Its simulation is possible based on a complex water quality model with parameters distribution. In this paper, we show that the model calculates the water flow with satisfactory accuracy and gives reliable values of phosphorus flow in the investigated river outlet. The influence of dryness of the year on the phosphorus flow is important and reduces dissolved phosphorus flow several times. The results of experiments with the model show a decrease of dissolved phosphorus flow subsequent to cease of fertilizing in range from 5 to 11%. The values of the surface and groundwater genetic components of phosphorus flow are comparable, while soil component amounts 65% of local phosphorus flow.

Measuring the Strength of Root-Reinforced Soil on Steep Natural Slopes Using the Corkscrew Extraction Method

Roots can help to stabilise slopes against landslides and anchor trees against wind loading, but their mechanical contribution to the strength of soil is difficult to rapidly quantify under field conditions. A new field measurement method, quantifying the shear strength of rooted soil by measuring the resistance against extraction of soil cores using a large corkscrew device, was tested across three heterogeneous slopes (unforested, forested and clearfelled) in Scotland. The presence of roots significantly increased the measured shear strength in the surface layer of the Sitka spruce forested slope. Differences in strength between the three areas were however not significant. This could be attributed to the large variation in the soil component of the combined root–soil shear strength, which was strongly affected by variations in both soil density and gravel content. Measured strength on these natural slopes were much more variable compared to previously investigated sites. These results highlight the importance of investigating the variation in soil strength during root-reinforcement measurements, and furthermore demonstrate the need for a sufficiently large number of tests to address this variation. The corkscrew provides rapid estimation of root-reinforced soil shear strength on sites with difficult accessibility. Compared to the more conventional shear vane method, which yielded comparable soil strength results, the corkscrew proved more suitable in stony soil layers and has the additional benefit of simultaneously extracting small (rooted) soil samples that could be used for further root and soil analysis. It therefore proved a useful and effective field tool for use when a rapid estimation of root-reinforced soil shear strength is required.