Some Physicochemical Properties of Soils from Three Steel Welding and Fabrication Workshops in Port Harcourt, Rivers State, Nigeria

Some physicochemical properties were assessed in soils within steel welding and fabrication workshops in Port Harcourt, Rivers State, Nigeria. The study was carried out between May to November, 2020. The physicochemical parameters were determined using standard conventional methods of analysis to ascertain the different levels of the selected physicochemical parameters in the studied environment. The results obtained within the months revealed that pH average range was between 6.8±0.08-7.1±0.05, the electrical conductivity average range was between 65.25±0.83-76±0.71µs/cm, percentage organic carbon was within average range of 0.396±0.001-0.525±0.001%, percentage soil organic matter was in the average range of 0.682±0.002-0.904±0.002% and for particle size analysis, percentage sand was in the average range of 75±0.71-79±0.71%, percentage clay was in the average range 9.25±0.83-11±0.71% and percentage silt was in the average range 10.75±0.43-14±0.71% for the Egbelu, Elioparanwo and Saint John soils respectively. Observation from the nature of occurrence of the physicochemical parameters in the steel-welding and fabrication workshops showed that that the steel-welding and fabrication has not yet influenced the level of the physicochemical parameters in the soils studied.

Impact of Small-Scale Mining Activities on Physicochemical Properties of Soils in Dunkwa East Municipality of Ghana

The quality of soils in rehabilitated small-scale mined sites needs thorough investigation since a lot of changes do occur. The study assessed the impacts of small-scale mining activities on concentration and distribution of soil physicochemical properties and heavy metals. The soil samples were collected from 120 (50 m × 50 m) plots. The concentrations of soil physicochemical properties (Ca, Mg, Na, N, P, K, and OC and EC) varied significantly ( p < 0.05) between unmined and mined soils. However, there were no statistically, significant differences ( p < 0.05) observed in the concentrations of Cd, Hg, Pb, As, and Cu between the unmined and mined soils. Despite the generally poor (33.8%) soil quality in the study area, mining activities further reduced it by 24.2%. Soils from mined sites with unfilled/partially filled pits had higher levels of K, Mg, and Na. As mined sites fallow period increased, concentrations of OC and Cd increased, while Ca, Mg, pH, Cu, Pb, and As and value of EC decreased. The number of years that mined land remained fallow, and whether the pits were filled or unfilled during this period should be factored into the mined land rehabilitation processes.

DYNAMICS IN PHYSICOCHEMICAL PROPERTIES OF SOILS UNDER OIL PALM PLANTATIONS OF DIFFERENT AGES

Removing forest cover for oil palm plantations has raised questions about climate change problems and debates and their associated impacts. The design of the pruned fronds of the trees does not make them ideal for use as mulch cover on the entire farm, but they are heaped between the plant rows. This research investigated the changes in the physicochemical properties of soils under oil palm plantations of different ages. Soil surface (0-20 cm) and subsurface (20-40 cm) samples have been obtained from various ages of oil palm plantations (0-5, 5-10, 10-15 and, 15-20 years). Two distinct samples were taken on the same farm, under alleys and heaped pruned fronds. Soil samples used as a standard (control) were collected from adjacent forest land. Analyses of particle size showed that the soils were sandy loam to sandy clay loam texture soils. Bulk density was low and varied with age and depth. The soils were moderate to slightly acidic pH, relatively low organic carbon, total nitrogen, and available phosphorus contents. Based on the standard ratings, exchangeable bases and cation exchangeable capacity content were also low, while high percent base saturation was observed. Research findings have shown that the soil properties of different ages of oil palm plantations vary and should therefore be handled differently based on of their characteristics. Accumulation of organic residue on the floor of the plantations should be encouraged as this will help to increase organic matter levels.

Soil quality of the tea and apple-growing sites in Mindat District, Chin state, Myanmar: A preliminary study

In this study, two sites from tea and apple growing sites were collected from Pyay village and Nine Mile village, Mindat district, Chin state of West Myanmar under a humid subtropical climate. The results of physicochemical properties of observed soils were neutral pH, favorable moisture, silty clay loam texture, very high content of organic carbon, organic matter and total nitrogen. However, the tea growing soil was very poor in phosphorus and potassium content. Moreover, both soils lack of available potassium. The content of heavy metals in both soils was not varied from each other and followed the order: Fe (iron) > Cu (copper) >Zn (zinc) > Pb (lead) > Cr (chromium) and was below the maximum allowed concentrations (MAC). Therefore, the studied soils are generally favorable for cultivation under the condition of application of phosphorus and potassium fertilizers. However, due to the regular application of fertilizers and pesticides, it is necessary to monitor these soils for PTE levels. Further research is recommended, which must include analyses of the physicochemical properties of soils to a two depths of 0-30 and 30-60 cm, especially for the area where fruit plants are grown. In addition, higher density of soil samples and sub-samples are necessary to produce a reliable dataset that will allow proper statistical analysis.

The Effects of Mesquite (Prosopis juliflora) on Soils and Plant Communities in the Deserted Rangelands of Bahrain

The influence of mesquite trees (Prosopis juliflora (Swartz) D.C.) on the physicochemical properties of soils and annual understory plants was investigated in the deserted rangelands of Bahrain. Soil properties were measured in the understory and the uncanopied adjacent areas of mesquite trees. Likewise, the number of plant species was assessed in four 1 × 1 m randomly distributed quadrates in the understory and the uncanopied adjacent areas. The results showed that sand particles exceed 96% of soil composition. Soil bulk density at the 0–5 cm soil depth was significantly higher in the understory of trees compared to the uncanopied adjacent areas. However, moisture at a depth of 40–60 cm was significantly higher in the uncanopied adjacent areas. No differences in the pH, EC, K, Na, and Ca were found between understory and the uncanopied areas in all soil depths. Levels of N, P, Mg, and organic matter were significantly higher in the understory of trees compared to the uncanopied adjacent areas. Organic matter was twice the amount in the upper 20 cm of soil layers in the understory of mesquite trees. Species richness did not differ between the understory and the uncanopied areas. Nevertheless, the density of ephemerals in the understory of mesquite trees was higher than the uncanopied areas by 18%. The Shannon-Weaver index of diversity was higher in the uncanopied areas compared to the understory. The study concluded that the canopy effects of mesquite trees on soil vary with depth. Nonetheless, the influence of mesquite on flora could be beneficial for annual understory plants but subject to many operating factors, including density and cover of mesquite trees.

CHANGE OF PROPERTIES OF ALPHE-HUMUS SOILS AS A RESULT OF TREE FELLING

On the territory of the Republic of Karelia, forest harvesting takes place in various ways. About 2/3 of the republic's forested area has been cut. Felling of the stand can be attributed to important anthropogenic factors, which in turn affects the dynamics of the structure and species composition of forests. The article discusses alpha-humus soils under stands that are at various stages of restoration after felling. The nature and dynamics of changes in the morphological and physicochemical properties of soils as a result of a change in woody and ground vegetation are considered.