Variability Of Soil Physico-chemical Properties Research Articles

The critical role of organic matter for cadmium-lead interactions in soil: Mechanisms and risks

Understanding the interaction mechanisms between complex heavy metals and soil components is a prerequisite for effectively forecasting the mobility and availability of contaminants in soils. Soil organic matter (SOM), with its diverse functional groups, has long been a focal point of research interest. In this study, four soils with manipulated levels of SOM, cadmium (Cd) and lead (Pb) were subjected to a 90-day incubation experiment. The competitive interactions between Cd and Pb in soils were investigated using Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and X-ray adsorption near-edge structure (XANES) analysis. Our results indicate that Pb competed with Cd for adsorption sites on the surface of SOM, particularly on carboxyl and hydroxyl functional groups. Approximately 22.6 % of Cd adsorption sites on humus were occupied by Pb. The use of sequentially extracted exchangeable heavy metals as indicators for environment risk assessments, considering variations in soil physico-chemical properties and synergistic or antagonistic effects between contaminants, provides a better estimation of metal bioavailability and its potential impacts. Integrating comprehensive contamination characterization of heavy metal interactions with the soil organic phase is an important advancement to assess the environmental risks of heavy metal dynamics in soil compared to individual contamination assessments.

Soil Degradation due to Long-term Citrus Cultivation in the Upper Vietnamese Mekong Delta

This study investigated the impact of tree age on soil properties in citrus orchards in the upper Vietnamese Mekong Delta province, examining orchards of four age groups (<10, 10–20, 21–30, and over 30 years) at two soil depths (0–20 cm and 20–50 cm). Findings indicate notable variations in soil physicochemical properties with age and depth. In older orchards (over 20 years), bulk density increased and soil pH decreased, with overall low pH values (3.5–5.0) observed. Electrical conductivity remained consistent across all ages. Key nutrients such as nitrogen (N), phosphorus (P), potassium (K), soil organic carbon (SOC), and cation exchange capacity (CEC) generally decreased with the age of the orchards. These trends were consistent across both soil layers. The study highlights the influence of prolonged cultivation on soil health and provides insights for developing strategies to enhance productivity and sustain agricultural practices in citrus orchards.

Effect of soil and water conservation practices and slope gradient on organic carbon stocks micronutrients: A case study on Kulkullessa sub-watershed, Eastern Ethiopia

Soil degradation in sub-Saharan Africa is a serious problem that causes declines in agricultural productivity linked to hunger and poverty. The study was conducted in the Kulkullessa sub-watershed of Goro Gutu District in Eastern Ethiopia to assess the effects of climate-smart soil and water conservation (SWC) practices and slope gradient on selected physicochemical properties of the soil and the soil’s organic carbon stocks. The farmland conserved by stone bund (SB), bench terrace (BT), and gras strip (GS) five years after construction with two slope gradients (15-20%) and (21-30%) was selected. Twenty-four composite soil samples were collected from a depth of 20 cm and tested in the Haramaya University soil laboratory. The study found that climate-smart SWC practices were very effective on the soil physicochemical properties and soil organic carbon stock (SOCS) of the study area. Similarly, the slope gradient brought considerable variation in soil physicochemical properties and soil organic carbon stock. On farmland that a bench terrace had preserved, the bulk density (BD) value was lower. The recorded value for total porosity on the farmland conserved by BT was also positively higher and significant (p ≤ 0.05). Likewise, the higher mean values for micronutrients and SOCS were recorded on farmlands conserved by SB, BT, and GS in contrast to the values recorded on non-conserved farmland (NCF) in the study area. Based on the study findings, climate-smart soil water and conservation practices have outstanding potential for improving soil physicochemical properties essential for agricultural crop production, climate change adaptation, and strengthening smallholder farmers’ resilience.

A comparative analysis of soil physicochemical properties and microbial community structure among four shelterbelt species in the northeast China plain.

The focal point of this study lies in the implementation of a controlled experiment conducted under field conditions. In this experiment, we deliberately selected four shelterbelts within the same field, characterized by identical planting density, and planting year. This deliberate selection effectively mitigated the potential impact of extraneous factors on the three microbiomes, thereby enhancing the reliability and validity of our findings.

Characterization of humic acids from soil of Delhi regions and their impact on plant growth

Humus materials are considered complex organic substances generated through a chain of chemical reactions and responsible for many processes in soil that ultimately govern soil health. The structural and functional characteristics of humus depend upon the location, quality, and microbial abundance of the soils. However, the differential characteristics of soil organic matter, seasonal changes, parent rock, plant cover, microbial abundance, and anthropogenic activities majorly affect it. The present study has aimed toward the extraction of humus from five different locations in the Delhi region of India and their characteristics were investigated through elemental analysis, Fourier Transform infrared (FT-IR) spectroscopy, and UV spectroscopy. The results showed that there was a higher degree of unsaturation detected in the Forest soil sample. The results of FT-IR showed the presence of characteristic peaks of humus in the samples however the intensity of bands was weak in sample disposable site soil sample and clayey soil sample due to the variation in soil physicochemical properties. The study also aimed to assess the growth of Oryza sativa (rice) plants observed in the hydroponics system. The significant finding was observed with the forest soil sample in 1000 mgL-1 and treatment in which the growth was minimum in clayey soil of 1500 mgL-1. Our investigation infers the diverse nature of humus in different soils and its implications for plant growth, highlighting the importance of understanding soil organic matter for sustainable agriculture and soil health management

Variations in soil physico-chemical properties, soil stocks, and soil stoichiometry under different soil layers, the major forest region Liupan Mountains of Northwest China.

Liupan Mountains are an important region in China in the context of forest cover and vegetation due to huge afforestation and plantation practices, which brought changes in soil physio-chemical properties, soil stocks, and soil stoichiometries are rarely been understood. The study aims to explore the distribution of soil nutrients at 1-m soil depth in the plantation forest region. The soil samples at five depth increments (0-20, 20-40, 40-60, 60-80, and 80-100 cm) were collected and analyzed for different soil physio-chemical characteristics. The results showed a significant variation in soil bulk density (BD), soil porosity, pH, cation exchange capacity (CEC), and electric conductivity (EC) values. More soil BD (1.41 g cm-3) and pH (6.97) were noticed in the deep soil layer (80-100 cm), while the highest values of porosity (60.6%), EC (0.09 mS cm-1), and CEC (32.9 c mol kg-1) were reflected in the uppermost soil layer (0-20 cm). Similarly, the highest contents of soil organic carbon (SOC), total phosphorus (TP), available phosphorus (AP), total nitrogen (TN), and available potassium (AK) were calculated in the surface soil layer (0-20 cm). With increasing soil depth increment a decreasing trend in the SOC and other nutrient concentration were found, whereas the soil total potassium (TK) produced a negative correlation with soil layer depth. The entire results produced the distribution of SOCs and TNs (stocks) at various soil depths in forestland patterns were 0→20cm > 20→40cm > 40→60cm ≥ 60→80cm ≥ 80→100 cm. Furthermore, the stoichiometric ratios of C, N, and P, the C/P, and N/P ratios showed maximum values (66.49 and 5.46) in 0-20 cm and lowest values (23.78 and 1.91) in 80-100 cm soil layer depth. Though the C/N ratio was statistically similar across the whole soil profile (0-100 cm). These results highlighted that the soil depth increments might largely be attributed to fluctuations in soil physio-chemical properties, soil stocks, and soil stoichiometries. Further study is needed to draw more conclusions on nutrient dynamics, soil stocks, and soil stoichiometry in these forests.

Seasonal dynamics of agricultural land use impacts on earthworm communities: Insights into diversity, abundance, and functional composition

Earthworms play a key role as soil bioengineers, but livestock farming and croplands can impact on the composition, structure, and functioning of earthworm communities. This study aimed to quantify the effects of replacing natural grasslands with crop rotations on the seasonal dynamics of key attributes of earthworm communities and explore soil physicochemical properties as mechanisms behind these effects. We conducted paired samplings on seven sites across Uruguay, comparing earthworm communities in soils under grazed natural grasslands and adjacent croplands, considering earthworm species composition, richness, diversity, and evenness, biomass, density, and mean body weight, over five consecutive seasons. Results revealed a clear negative impact of croplands on earthworm communities, showing substantial reductions in all considered attributes. Observed changes were attributed to environmental filters limiting the occurrence of larger exotic earthworm species in croplands, and variations in soil physicochemical properties were identified as potentially mediating some of these effects, including soil water regime (particularly affecting juvenile individuals) and soil organic matter content. These impacts resulted in a shift to dominance of r strategists (smaller, surface-feeding species such as Microscolex spp. in croplands compared to larger deeper-burrowing species in grasslands) and reduced functional composition of earthworm communities. Furthermore, seasonal dynamics revealed that differences between land uses were more pronounced during wetter periods, underscoring the relevance of seasonal variations when evaluating land use impacts on earthworm communities. Earthworms mean body weight resulted a useful attribute to be included in earthworm's assessments, allowing to identify impacts in community functional composition and suggesting size dependent mechanisms. Additional research is required to comprehensively understand the mechanisms behind these patterns and to develop more sustainable agricultural practices by considering soil fauna.

Spatial Assessment and Variation of Soil Physicochemical Properties and Water Quality in the Tungi Watershed of Maharashtra, India

Aims: To thoroughly evaluate the spatial variability of soil physicochemical properties and groundwater quality of the study area by systematic collection and analysis of geo-referenced soil and groundwater samples to quantify the physical, chemical and biological attributes of the soil. The objective is to gain a comprehensive understanding of soil and water quality in the Tungi watershed, providing valuable insights to guide sustainable land and water management practices in the region.
 Place and Duration of Study: Department of Soil Science and Agricultural Chemistry, College of Agriculture, Latur between 2020 and 2021.
 Methodology: A total of one hundred geo-referenced surface soil samples (0-30 cm) and ten groundwater samples were methodically collected from the surrounding area of soil profiles in the Tungi watershed, situated in Latur, Maharashtra. Physical, chemical and biological properties of soil evaluated using recommended standard methods.
 Results: Bulk density varied from 1.13 to 1.93 Mg m-3, particle density from 2.48 to 2.94 Mg m-3 and porosity from 22 to 58 percent. Soil pH ranged from 7.05 to 8.96 and electrical conductivity was within the permissible range. Organic carbon content of soils ranged from 0.15 to 1.05 percent, with some soils having a calcareous character (0.6 to 22.2 percent). The analysis of nutrient content revealed variable quantities with available nitrogen ranging from 53.31 to 250.88 kg ha-1, available phosphorus from 12.51 to 27.49 kg ha-1, available potassium from 106.9 to 851.5 kg ha-1 and available sulphur from 4.37 to 66.65 mg kg-1. Exchangeable calcium and magnesium quantities revealed ranges of 14.60 to 42.40 cmol(p+) kg-1 and 5.40 to 21.60 cmol(p+) kg-1, respectively. Furthermore, DTPA extractable iron varied from 4.24 to 16.38 mg kg-1, manganese from 4.76 to 25.84 mg kg-1, zinc and copper from 0.5 to 6.56 mg kg-1 and 0.72 to 15.56 mg kg-1, respectively and boron from 0.1 to 3.56 mg kg-1. Microbial population estimates revealed the dominance of bacteria over fungi and actinomycetes in the studied area. Groundwater carbonate and bicarbonate ranged from 0.01 to 0.62 m mol-1 and 6.35 to 10.24 mmol-1 respectively. The dug well, bore well and tube well water RSC ranged from 0.70 to 1.25 mmol-1.
 Conclusion: This extensive study provides helpful insights into the regional variability of physical and chemical properties in both soil and water with help of soil fertility maps, providing better understanding of soil fertilizer input and environmental conditions in the Tungi watershed.

Fine‐root turnover and leaf litterfall of Salsola passerina facilitate soil restoration in Alxa steppe desert of northwest China

Nutrient cycling in desert ecosystems is heavily reliant on the fine root turnover and litter decomposition processes of dominant plant species. Based on field investigations and laboratory experiments, we explored fine root production (FRP) and turnover of Salsola passerina in Alxa steppe desert, and assessed fine root and leaf litter input and its correlation with soil C and N stocks, and then compared the variability of soil physicochemical properties at the site below and the interspace of S. passerina canopy. Results showed that fine root biomass dynamics of S. passerina were consistent with soil water content. Annual FRP of S. passerina was 243.3 g m−2 yr−1 and the turnover rate was 2.0 per year. S. passerina contributed 172.2 g C m−2 and 6.8 g N m−2 to soil from its fine root senescence and leaf litter input annually. Compared to the canopy interspace, the soil texture and fertility beneath the shrubs significantly improved, while the soil salinity decreased. The results indicated that the activities of desert shrub growth provided the degraded soil with abundant nutrients through fine root turnover and litter decomposition processes, which promoted soil texture and nutrition heterogeneity at the stand scale, and played an important role in degraded dryland restoration.

Variation in Soil Physicochemical Properties of Different Land Use Types in Abakaliki, South Eastern Nigeria

The effect of land use on soil physicochemical properties was evaluated in soils of Abakaliki, south eastern Nigeria. The four land use types selected are managed Gmelina plantation (MP), fallow land (FL), grass land (GL) and continuously cultivated soil (CCS). Soil samples (undisturbed and auger) were collected from three soil depths of 0 – 20 cm, 20 - 40 cm and 40 – 60 ¬¬_ cm for physicochemical properties analysis. Bulk density was significantly (P < 0.05) lower (1.33 – 1.50 gcm-3) in FL across the depths than other land use types. The pH of the soils was moderately to slightly acidic. Soil organic carbon, total nitrogen and available phosphorus were significantly higher (P < 0.05) in FL than others and followed the trend FL>MP>GL>CCS. The exchangeable acidity was significantly different among the land use type but was the highest in MF (2.20) and the lowest in (GL). Across the soil depths, 0-20 _cm recorded higher values for bulk density, saturated hydraulic conductivity, soil organic carbon, total nitrogen and available phosphorus compared to other soil depths. In all, FL, MF and GL recorded higher values for most soil properties studied, while CCS recorded lower values. There was a decline in most of the properties studied due to continuous cultivation. How to Cite: Orji J. E., Igwe C. A., Osuji E. E., et. al., 2023. "Variation in Soil Physicochemical Properties of Different Land Use Types in Abakaliki, South Eastern Nigeria." Journal of Agriculture and Crops, vol. 9, pp. 462-471.

Spatial Variations in Soil Physicochemical Properties and Enzyme Activities in the Low Mountain Area of Helan Mountain

Spatial Variations in Soil Physicochemical Properties and Enzyme Activities in the Low Mountain Area of Helan Mountain

SPATIAL VARIABILITY OF SOIL PHYSICOCHEMICAL PROPERTIES AND HEAVY METAL CONCENTRATIONS IN OWERRI MUNICIPAL DUMPSITES

Heavy metals pose a serious threat to our environment due to the fact that majority of annual vegetable crops consumed by man and animal are produced from the polluted sites without knowing the level of it taken up by plant which revolves into food chain. This study evaluated the variability of soil physicochemical properties and heavy metals concentration in Owerri municipal dumpsites in Imo State. Samples were collected in three replicates 0, 5 and 10m away from refuge dumpsites at 0 - 30cm depth using soil auger in Ihiagwa, Avu, Abazu and Obinze. Samples were analyzed for soil properties and heavy metals-concentrations using standard methods. The concentrations of the studied heavy metals (Pb and Cr) were compared with the permissible limits of other countries. pH results from the analyzed sampled soils from the four locations were high (6.89, 6.80, 6.59 and 6.40) in Ihiagwa, Abazu, Obinze and Avu respectively while organic carbon followed the trend Ihiagwa>Avu>Abazu>Obinze. Organic carbon and total Nitrogen concentrations followed the same trend in Ihiagwa, Avu, Abazu and Obinze. Pb concentrations in the studied sites were above the standard limit recommended (0.05mg/kg) by Federal Environmental Protection Agency but within limit (100mg/kg) stipulated by European Commission. Nevertheless, Pb concentration was within the tolerance limit set by European Union but should be cautiously minimized to prevent health hazard on man and the environment. The use of refuge dumpsite for cultivation of arable crops should be avoided and lands on cultivation should be given a distance from the refuse sites.

Mapping Spatial Variability of Soil Physico-Chemical Properties and Available Nutrient Status and Assessment of Irrigation Water Quality of ICAR-KVK Farm, Pongalur

The study was conducted at the Department of Soil Science and Agricultural Chemistry to collect geo-referenced soil and water samples, analyze their soil physico-chemical properties, and quality parameters, and prepare thematic maps to suggest suitable management practices. The soils were slightly calcareous and non-saline. The available N, P and K status were low, medium and high respectively, with low to moderate OC content. The available Ca, Mg and S status of the soil were high and medium to high, respectively. The DTPA-Zn values and DTPA-Fe values were deficient DTPA Cu and DTPA-Mn values were sufficient in the farm soils. The HWS boron values were sufficient. The water samples of the farm had neutral to slightly above neutral pH, and the EC of the water sample ranges from 0.63 to 4.08 dS m-1. The chloride content of the water sample ranged from 2.00 to 22.80 meq L-1. There was no CO3 2- and SO4 2- contents observed in water. SAR value of samples lies between 1.51 and 4.19 and the adjusted SAR value varies from 2.87 to 10.48 indicating good quality of water samples

Effects of Biochar on the Microenvironment of Saline-Sodic Soil and Maize Growth

Biochar is a valuable soil amendment substance. However, no systematic study has investigated the effects of biochar on the microenvironment of saline-sodic soils and maize yield in cold areas of Heilongjiang Province. We investigated variations in soil physicochemical properties, soil bacterial and fungal community structure, maize root formation, plant dry matter accumulation, grain filling rate, and maize yield in saline soils treated with biochar (0, 20, 40, and 80 t/ha). Biochar improved saline soil properties and structure, slightly decreasing bulk density and pH and increasing the water-stable aggregate stabilization rate. Furthermore, the relative abundances of Sphingomonas, Lysobacter, Nitrospira, and Gemmatimonas and the fungal genus Guehomyces were increased, promoting the conversion of soil organic carbon and available nitrogen and phosphorus. Moreover, biochar reduced the relative abundance of some fungal pathogenic genera, including Fusarium, Gibberella, Cladosporium, Alternaria, and Epicoccum. However, shifts in soil bacterial and fungal community structure were indirectly driven by biochar-induced changes in soil physicochemical properties, with organic carbon as the most critical. Biochar promoted maize growth, development, and yield (root length, surface area, volume, dry matter accumulation, grain filling rate, and final weight). Biochar application at 40 t/ha had the greatest effect on soil microenvironment improvement, with the highest maize yield.

Spatial Variation in Soil Physico-Chemical Properties along Slope Position in a Small Agricultural Watershed Scale

Both cropland management and slop erosion are important factors influencing soil properties, but there are relatively few studies on their combined effects. Studies at the agricultural watershed scale can satisfy both of these conditions, and to reduce the effects of soil heterogeneity due to differences in spatial scale, it is better to select different slopes in the same small watershed. To understand how soil properties will respond to the variation of slope position and cropland management at an agricultural watershed, we present the distribution of soil bulk density (BD), saturated hydraulic conductivity (Ks), water-stable aggregates, soil organic carbon (OC), nitrogen (N), and phosphorus (P) at four slope positions in two cropland management systems of a small agricultural watershed in the black soil region of northeast China. The selected four slope positions include upper slope, middle slope, lower slope, and footslope positions. The two cropland management systems consist of a sustainable cropland system (i.e., contour ridge tillage at upper slope position, longitudinal ridge tillage at middle slope and lower slope positions, and grassland at footslope position) and a conventional cropland system (i.e., contour ridge tillage at upper slope position, longitudinal ridge tillage at middle slope, lower slope positions, and footslope positions). The results showed that soil bulk density and microaggregates decreased but the concentration of OC and nutrients, Ks, and small-macroaggregate increased from the upper slope position to the lower slope position in both the conventional and sustainable croplands, which was due to the interaction effect of cultivation with erosion. In comparison with conventional cropland, sustainable cropland has greater Ks, large-macroaggregate, small-macroaggregate, microaggregate, and concentrations and stocks of OC, N, and P, but showed lower bulk density and silt + clay fraction. However, the prominent differences in both croplands were presented in the footslope position, which is ascribed to the interaction of cultivation, erosion, and cropland management. These results highlighted that sustainable cropland management practice has the potential to improve soil structure and prevent soil and nutrient loss.

Short-term recovery of soil and pine tree canopy after late prescribed burning in a semi-arid landscape

Climate change worsening due to global warming and progressive abandonment in rural areas mean that wildfires are increasing in extent and severity terms, and are one of the major disturbances in the Mediterranean Basin. To mitigate these disturbances, preventive management tools need to be used. Fire employment is being implemented, known as prescribed burnings, as forestry actions to change vegetation lines both vertically and horizontally to eliminate forest fuel load continuity. This study aimed to know the ecological effects of late prescribed burning treatments under mixed trees. Prescribed burns were carried out in October 2019 in the municipality of Ayna, Albacete (SE Spain). To assess the short-term (12-month) fire impact on soil, we measured soil respiration with a CO2 flow chamber and analyzed soil physico-chemical properties. We also used minidisc infiltrometers to analyze soil repellency and soil hydraulic conductivity over a 1-year monitoring period. In addition, we evaluated the effects on tree strata by performing chemical nature analyses of fallen needles in Pinus pinaster after prescribed burning. According to our initial hypotheses, the results did not show significant changes in any parameter evaluated during the study period. However, some variables were affected in the first 3 months, needlefall and in microbiological activity, such as variations in soil physico-chemical properties, which can be due to long dry seasons combined with prescribed burning. This study attempts to observe and make known the effects that low-intensity prescribed burning has on soil and needlefall, which are relevant for updating forest management tools.

Variability of soil physicochemical properties under different land use types in the Guinea savanna zone of northern Ghana

Variability of soil physicochemical properties under different land use types in the Guinea savanna zone of northern <i>Ghana</i>

Variations in soil properties and stoichiometric ratios with stand age under agarwood monoculture and polyculture on smallholder farms

Smallholder plantations have gained increasing attention in land management and conservation of the remaining forest resources locally. Plantation of agarwood (Aquilaria malaccensis), a critically endangered tree species, has become a promising source of income for smallholders because of its high economic value in parts of Asia. Agarwood is considered profitable with plantation cycles of 15 years or more. The objectives of the present study are to (i) quantify variations in soil physico-chemical properties, (ii) quantify variations in soil organic carbon (SOC) stocks, and (iii) evaluate variations in stoichiometric ratios with stand type, age and soil depth. Soil texture, bulk density, water holding capacity (WHC), soil pH, available nitrogen (N), phosphorus (P), potassium (K), exchangeable calcium (Ca), magnesium (Mg) and soil organic carbon (SOC) stocks in very labile, labile, less labile and non-labile pools were determined in different soil depths (0–100 cm) under <10, 10–20 and >20 years old monoculture and polyculture stands of agarwood on smallholder farms. Soil texture and bulk density did not significantly vary with stand type or age, but significantly higher WHC was found in >20 years old stands. Across stand ages and soil depths, available N and P concentrations were higher in monoculture, while available K concentrations were higher in polyculture. SOC content significantly varied with the stand type, age and soil depth and their interaction effects. The highest SOC content (28.9 g kg−1) was recorded in the 0–10 cm of >20 years old monoculture stands, while the lowest (4.2 g kg−1) in the 51–100 cm depth of 10–20 years old polyculture stands. SOC stocks significantly increased with increase in stand age in both monoculture and polyculture stands. The highest total SOC stock (40.7 Mg ha−1) was recorded in the 51–100 cm depth of >20 years old monoculture stands, while the lowest (13.4 Mg ha−1) was in the 31–50 cm depth of <10 years old polyculture stands. The SOC stocks in the recalcitrant (passive) pools, which are the main drivers of long-term soil carbon sinks, were 1.5-fold more in monoculture than polyculture stands.

Variations in Soil Physico-Chemical Properties as Influenced by Landuse in a Toposequence

Soil, water and air work interchangeably for optimum growth and productivity. Soil as a resource provides crops with essential nutrients necessary for growth and human consumption. With the insurgence of high population growth leading to pressure on lands, poor land management etc., this tendency of the soil as a nutrient pool is seen to be dwindling. It is therefore prudent to investigate and understand the dynamism of soil properties to inform proper management. Understanding topography effects and assessing soil properties on different slope positions is a first-hand step in ensuring proper soil management practices. This paper considers the assessment of physico-chemical properties of soils located on different slope gradients and land use types on the Wamaso research site in Ghana made principally of cape coast granite. In all, eighteen samples were collected from identified horizons of five distinctive subsections of the slope were delineated as follows, summit (PP1), shoulder (PP2), middle (PP3), foot slope (PP4) and toe slope (PP5) respectively. Remarkable variations were observed within PP1 to PP3 and then PP5. Pearson’s correlation index revealed that the associations between most of the soil physico-chemical were not consistent across the identified slope positions. The biplot of the first two principal components together is 68.3% of the total variation and might be interpreted as change in Cation exchange capacity, sodium, sand and clay. On the first axis highlights the influence of sand and clay on soil fertility, also the relationship between pH and Na. Organic carbon derived from organic matter contributes to the availability of the basic soil cations and therefore enhances ECEC of the soils and hence the relationship obtained from the biplot. In sum, this research achieved the objective which sought to substantiate indeed the impact topography has on soil physico-chemical properties thereby serving as a reference for the classification of the soils identified.

Variation in Soil Physico-Chemical Properties in Temperate Forests of Khatling Valley, Western Himalaya, India

The current study seeks to understand the physico-chemical properties of soil along different altitude in Khatling valley of Western Himalaya. Four sites were examined for different physico-chemical characteristics between 1500-3500m amsl. The investigation found that the soils at all of the study sites were acidic and had a sandy loam texture. The range of the water holding capacity and moisture content values across the research area was 35.59±4.22 to 38.91±3.97% and 14.77±0.12 to 17.39±1.13% respectively. In the studied area the values for total nitrogen ranged from 0.19±0.02 to 0.37±0.04%, available phosphorus (10.23±2.45 to 15.97±2.63kg ha-1), available potassium (122.95±17.58 to 212.90±19.67kg ha-1), organic carbon (0.92±0.35 to 3.09±0.63%) and organic matter (1.58±0.60 to 5.32±1.09%) respectively. Organic carbon and total nitrogen displayed a positive correlation with altitude (r = 0.992 and r = 0.865, respectively) but a negative correlation with soil depth. In contrast, there was a negative association between altitude and the amounts of available phosphorus (r = -0.941) and potassium (r = -0.941). The available phosphorus indicates a positive relation with the depth of soil, whereas available potassium did not exhibit a consistent pattern with depth. This finding of this study suggest that soil physico-chemical properties vary with altitude and soil depth.