Analysis Of Soil Bulk Density Research Articles

Effects of Eucalyptus species on soil physicochemical properties in Ruhande Arboretum, Rwanda

This study combines research on soil physical and chemical properties as affected by four Eucalyptus species in Ruhande arboretum. The soil samples for research properties were taken from 0-20 cm depth using auger and one undisturbed core from each sampling unit was taken for the analysis of soil bulk density. Soil bulk density and moisture did not differ significantly between all treatments. Sand proportions differed significantly only between E. tereticornis and E. maidenii whereas silt and clay were non-significant. The soil under Eucalyptus was sandy, with sand proportion ranging from 66.4-71%. Bulk density increased with increasing sand whereas moisture content showed a reverse trend. The soil samples for studying chemical properties were taken as described in Nsabimana et al. 2008. All chemical parameters except base saturation differed significantly between treatments. Soil pH was strongly acidic but rich in total nitrogen and organic carbon which was attributed to higher litter production, its relatively faster rate of decomposition, and greater amount of residues produced by the eucalypts. Carbon/nitrogen ratio, CEC, and BS were high under all treatments while the available phosphorus was lower which was attributed to the low pH. Future studies should test if the species similarly affect the soil or not and confirm if the species increase soil nutrients. Benchmarked study sites should be used to enable differences in the species effects on the site if any.

Spatiotemporal Dynamics of Forest Vegetation and Their Impacts on Soil Properties in the Forest-Steppe Zone of Central Russian Upland: A Remote Sensing, GIS Analysis, and Field Studies Approach

This article showcases the outcomes of a comprehensive spatiotemporal dynamic analysis conducted in forest vegetation areas within the forest-steppe zone of the Central Russian Upland (eastern Europe), spanning the period from 1970 to 2020. This study utilized high-resolution data from the Corona satellite system from the year 1970 as well as satellite imagery from the ArcGIS World Imagery database. Soil properties and their changes were assessed based on the analysis of soil bulk density (930 samples), soil organic carbon features, pH, available phosphorus, and the composition of salt extracts (1362 samples). We collected and analyzed 3920 soil samples in the field to study the impact of shelterbelts on soil moisture over a period of two years. For six selected key sites with a total area of 1722 km2, it was found that over a 50-year period, the area covered by forest vegetation increased from 14% to 24%. This expansion was primarily due to the planting and growth of young shelterbelts in the 1970s–1980s as well as widening anti-erosion shelterbelts on slopes and gullies. The average linear growth rate of forest vegetation boundaries was found to be 23.5 m (4.7 m per decade) for the entire study area. The expansion was highest on west-facing slopes, which was attributed to the higher moisture content from windward atmospheric precipitation events. However, alongside the increase in forest cover, degradation was also observed, particularly in old-age shelterbelts, which was attributed to increased fragmentation and mortality. A gradual increase in the extent of shelterbelt degradation was observed from the northwest to the southeast within the forest-steppe region, corresponding to areas with a drier climate. Additionally, the impact of shelterbelts on soil properties and soil cover was analyzed using four key sites and using fields and laboratory research methods. We detected a lateral uptake of substances from plowed soils into the soils of shelterbelts and vertical uptake from deep layers. The two-year observations (2020 and 2021) of soil moisture during the growing season (May–September) in two climatically contrasting forest-steppe areas revealed a more intensive accumulation of soil moisture in fields west of shelterbelts compared to those to the east of them, particularly within the 10 m zone near the shelterbelts. This can be attributed to arable fields on the windward side receiving more moisture compared to the leeward side. The formation of striped microstructures in the soil cover that occurred under the shelterbelts and on adjacent arable lands was influenced by various factors such as microclimatic conditions, vegetation types, ecological conditions for soil fauna, and human-induced soil processing and transformation along the shelterbelt boundaries. Shelterbelts and their adjacent areas in agro-landscapes are considered to be self-developing natural–anthropogenic geosystems with their own organizational structure. Therefore, their study is recommended as an integral part of modern geographical zoning.

Soil and Root System Attributes of Forage Cactus under Different Management Practices in the Brazilian Semiarid

Drylands cover 40% of the global surface and house more than 2 billion people. Drought-tolerant crops are becoming more important in these regions, not only to provide food, fodder, and energy, but also to sequester soil organic carbon. This study evaluated soil and root system attributes of forage cactus ‘Orelha de Elefante Mexicana’ (Opuntia stricta Haw.) managed using different agronomic practices in the Brazilian Semiarid. The experiment was established in June 2011 and the design was split-plot in a randomized complete blocks, where the main plot was the different planting density, and the subplots were the factorial arrangement between harvest frequency and harvest intensity. Soil samples were collected at 0 to 10 and 10 to 20 cm depths and response variables included root biomass, soil bulk density (BD), and soil carbon (C) and nitrogen (N) contents and stocks. Sampling occurred in August 2019, but for root biomass and soil BD analysis it also occurred in September 2021. There were no significant effects from management practices on root biomass at 0 to 10 and 10 to 20 cm depth (p > 0.05), with respective averages of 12.45 Mg ha−1 and 6.06 Mg ha−1. Soil BD was similar at 10 to 20 cm depth (p > 0.05) averaging 1.28 g cm−3. Soil organic carbon (SOC) stock varied with management and reached almost 100 Mg C ha−1 in the 0 to 20 cm layer, indicating the potential of cactus to store carbon. Plants with a more developed root system are more likely to survive the drought climatic condition; therefore, less dense plantings could result in more resilient plants for drier regions, but could potentially negatively affect biomass productivity per area.

Deep Tillage Strategies in Perennial Crop Installation: Structural Changes in Contrasting Soil Classes.

Tillage modifies soil structure, which can be demonstrated by changes in the soil’s physical properties, such as penetration resistance (PR) and soil electrical resistivity (ρ). The aim of this study was to evaluate the effect of deep tillage strategies on three morphogenetically contrasting soil classes in the establishment of perennial crops regarding geophysical and physical-hydric properties. The experiment was conducted in the state of Minas Gerais, southeastern Brazil. The tillage practices were evaluated in Typic Dystrustept, Rhodic Hapludult, and Rhodic Hapludox soil classes, and are described as follows: MT—plant hole; CT—furrow; SB—subsoiler; DT—rotary hoe tiller; and DT + calcium (Ca) (additional liming). Analyses of PR and electrical resistivity tomography (ERT) were performed during the growing season and measurements were measured in plant rows of each experimental plot. Undisturbed soil samples were collected for analysis of soil bulk density (Bd) at three soil depths (0–0.20, 0.20–0.40, and 0.40–0.60 m) with morphological evaluation of soil structure (VESS). Tukey’s test (p < 0.05) for Bd and VESS and Pearson linear correlation analysis between Bd, ρ, and PR were performed. Soil class and its intrinsic attributes have an influence on the effect of tillage. The greatest effect on soil structure occurred in the treatments DT and DT + Ca that mixed the soil to a depth of 0.60 m. The ρ showed a positive correlation with Bd and with PR, highlighting that ERT may detect changes caused by cultivation practices, although ERT lacks the accuracy of PR. The soil response to different tillage systems and their effects on soil structure were found to be dependent on the soil class.

Relationship Analysis of Soil Bulk Density, Available K, and Slope to Productivity of Salak Pondoh at Padang Jaya, North Bengkulu

Salak (Zalacca edulis Gaertn. Voss) is one of the most populair native fruits of Indonesia, consumed as a table fruit by most Indonesians. However, the yield of salak pondoh grown in Bengkulu is still lower than that in their native soil Java, believed to have more suitable soil properties for growing salak pondoh. The objective of this research were to evaluate the relationship of soil bulk density, available K, and slope to the productivity of salak pondoh grown at Padang Jaya Regency, North Bengkulu. We did a survey to collect data on soil bulk density (BD), available K (K), and slope as well as the productivity of salak pondoh grown at Padang Jaya from November 2017 to May 2017. The results showed that there was a significant relationship between soil characteristics and salak productivity, as shown in a linear model of Y = 2.929 -1.070 BD + 0.069 K - 0.126 Slope. Soil K was positively correlated to salak productivity, suggesting that salak productivity increased with an increase in soil K. On the other than, soil bulk density and slope were negatively correlelated to salak productivity, indicating that salak productity decreased with an increase in slope and in soil bulk density.

Detecting the environmental impact of off-road vehicles on Rawdat Al Shams in central Saudi Arabia by remote sensing.

Off-road vehicles can have a devastating impact on vegetation and soil. Here, we sought to quantify, through a combination of field vegetation, bulk soil, and image analyses, the impact of off-road vehicles on the vegetation and soils of Rawdat Al Shams, which is located in central Saudi Arabia. Soil compaction density was measured in the field, and 27 soil samples were collected for bulk density analysis in the lab to quantify the impacts of off-road vehicles. High spatial resolution images, such as those obtained by the satellites GeoEye-1 and IKONOS-2, were used for surveying the damage to vegetation cover and soil compaction caused by these vehicles. Vegetation cover was mapped using the Normalized Difference Vegetation Index (NDVI) technique based on high-resolution images taken at different times of the year. Vehicle trails were derived from satellite data via visual analysis. All damaged areas were determined from high-resolution image data. In this study, we conducted quantitative analyses of vegetation cover change, the impacts of vehicle trails (hereafter "trail impacts"), and a bulk soil analysis. Image data showed that both vegetation cover and trail impacts increased from 2008 to 2015, with the average percentage of trail impacts nearly equal to that of the percentage of vegetation cover during this period. Forty-six species of plants were found to be present in the study area, consisting of all types of life forms, yet trees were represented by a single species, Acacia gerrardii. Herbs composed the largest share of plant life, with 29 species, followed by perennial herbs (12 species), grasses (5 species), and shrubs (3 species). Analysis of soil bulk density for Rawdat Al Shams showed that off-road driving greatly impacts soil density. Twenty-two plant species were observed on the trails, the majority of which were ephemerals. Notoceras bicorne was the most common, with a frequency rate of 93.33%, an abundance value of 78.47%, and a density of 0.1 in transect 1, followed by Plantago ovata.

Systematic Evaluation of Kriging and Inverse Distance Weighting Methods for Spatial Analysis of Soil Bulk Density

Spatial interpolation methods are frequently used to characterize spatial phenomena in soil properties over various spatial scales; however, it is very difficult to select the best interpolation method. No specific standards or tests are available to determine the “appropriateness” of an interpolation model. This study focused on evaluation of the performance of two widely used interpolators: kriging and inverse distance weighting (IDW) for the spatial analysis of soil bulk density. Predicted values by both interpolation models were compared with the observed data and analyzed using various indices. Results indicated that both interpolation methods do not reflect true variation of bulk density. Both models, however, performed equally well for spatial analysis with almost the same accuracy, precision and consistency with a difference of less than 1.0%, 0.5% and 2.0%, respectively. Inverse distance weighting method, simpler than kriging method, gives competitive and somewhat superior results when an optimal power value is used. No relation was found among coefficient of variation, skewness and kurtosis in selecting an appropriate interpolation method for spatial description or selecting a power value for IDW method or a semivariogram model for the kriging method. This study has provided an example of an approach to systematically evaluate the performance of one or more spatial interpolation methods. By employing the validation indices used in this study, any interpolation method can be assessed to accurately describe any spatial data set from the field.

Systematic Evaluation of Kriging and Inverse Distance Weighting Methods for Spatial Analysis of Soil Bulk Density.

Systematic Evaluation of Kriging and Inverse Distance Weighting Methods for Spatial Analysis of Soil Bulk Density.

Gamma-ray computed tomography to evaluate changes in the structure of a clayey soil due to agricultural traffic

A first generation gamma-ray computed tomography (CT) equipped with a 137Cs source was used to investigate changes in soil structure due to agricultural machinery traffic. Core samples with volume of 55 cm3 were collected at the surface (0-10 cm) of a Brazilian clayey soil. Significant alterations in soil structure occurred after two passages of tractor wheels, with important decreases in soil porosity. CT data allowed a continuous analysis of soil bulk density and also soil porosity distribution for 1.25 and 1.20 mm layers, which cannot be provided by traditional methods commonly used in soil physics.

Mudanças na estrutura do solo avaliada com uso de tomografia computadorizada

O objetivo deste trabalho foi avaliar, em escala milimétrica, a modificação da densidade e da porosidade de amostras deformadas de solo submetidas a ciclos de umedecimento e secamento (U-S), por meio da tomografia computadorizada de raios gama. Amostras com 98,1 cm³ foram preparadas procedendo ao peneiramento do solo em malha de 2 mm e acondicionamento de forma homogênea em tubos de PVC. As amostras de solo foram submetidas a um, dois e três ciclos de U-S. As amostras controle não foram submetidas a nenhum ciclo de U-S. Após a aplicação dos ciclos de U-S, a porosidade das amostras diminuiu e as camadas de solo se adensaram. Os dados de tomografia computadorizada permitiram análise contínua da densidade do solo e de sua porosidade, em camadas milimétricas (0,08 cm), o que não pode ser alcançado facilmente por métodos tradicionais usados em física do solo.

Spatial Variability Analysis of Soil Physical Properties of Alluvial Soils

Analysis and interpretation of spatial variability of soils is a keystone in site‐specific farming. Soil survey maps may have up to 0.41‐ha inclusions of dissimilar soils within a mapping unit. The objectives of this study were to determine the degree of spatial variability of soil physical properties and variance structure, and to model the sampling interval of alluvial floodplain soils. Soil profiles (n= 209) from 18 parallel transects were sampled with a mean separation distance of 79.4 m. Each profile was classified into surface, subsurface, and deep horizons. Structural analysis of soil bulk density (ρb), sand, clay, saturated hydraulic conductivity (Ks), volumetric water content (θv) at seven pressure potentials (Ψa) (−1, −10, −33, −67, −100, −500, and −1500 kPa) were modeled for the three horizons. Variance of soil physical properties varied from as low as 0.01% (ρb) to as high as 1542% (Ks). The LSD test indicated significant (P&lt; 0.05) differences in sand, clay, ρb,Ks, and θvat various ΨaGeostatistical analyses illustrated that the spatially dependent stochastic component was predominant over the nugget effect. Structured semivariogram functions of each variable were used in generating fine‐scale kriged contour maps. Overall autocorrelation, Moran'sI, indicated a 400‐m sampling range would be adequate for detection of spatial structure of sand, silt, clay, and a 100‐m sampling range for soil hydraulic properties and ρbThe magnitude and spatial patterns soil physical property variability have implications for variable rate applications and design of soil sampling strategies in alluvial floodplain soils.

SOIL BULK DENSITY, SOIL STRENGTH, AND REGENERATION OF A BOTTOMLAND HARDWOOD SITE ONE YEAR AFTER HARVEST

The first year soil physical properties and regeneration measurements following harvest indicate ampleregeneration on all treatments including the landing areas. Comparisons included three machine systems (three skidders)and a helicopter-yarded control that were field tested for harvesting a bottomland hardwood site under adverseconditions. The results also demonstrate a significantly greater number of tree stem count following the winter than thesummer harvest. Results of the statistical analysis of soil bulk density indicate that the soil had partially recovered frommachine traffic one year after harvest.

Soil Bulk Density Analysis in Three Dimensions by Computed Tomographic Scanning

AbstractCurrent soil bulk densitometric techniques lack the precision to detect three‐dimensional changes in density in a nondestructive manner. The x‐ray transmission computed tomography (CT) scanner was evaluated as a tool to determine soil bulk density. This scanner is an advanced tool in diagnostic radiology used to obtain a nondestructive cross‐sectional representation of the human body. Typical accuracy and precision for CT scanners are known for materials like human tissue with a linear attenuation coefficient near water. Machine response was evaluated near the upper limit of the measurement range where denser materials, such as soil, are located.Scanner analyses of soil and glass bead‐air filled sphere samples that varied in bulk density from 0.14 to 1.64 g/cm3 revealed that a positive linear response occurred with increasing density. For the Metea sandy loam soil (Arenic Hapludalfs), this CT scanner was found to have precision in the order of 19 mg/cm3. Spatial resolution or the ability to distinguish between two objects in the scanning plane was found to range from 1.25 by 1.25 by 2 mm3 to 6.4 mm in diameter by 2 mm. The greater resolution was obtained when density within the sample varied greatly. Errors in data can occur as a result of certain machine artifacts; however, many of these can be avoided by relatively simple methods.It was concluded that the CT scanner can be used to determine soil bulk density with good three‐dimensional spatial resolution. This is a potentially promising tool for research in the areas of compaction, soil management, and cultivation.