scholarly journals Nutrient reserves in Southland soils

Author(s):  
C.C. Boswell ◽  
W.H. Risk ◽  
R.P. Littleiohn ◽  
B. Swanney ◽  
G.M. Gray ◽  
...  

The major plant nutrients in soils were measured from 53 Southland sites arranged along 4 transects which extended inland from the southern coast and one which extended westwards from Papatowai on the east coast to Manapouri in the west. Soil samples were taken from 8 depths: O-75.75-150, 150-225, 225-300, 300-450, 450-600, 600-750, and 750-900 mm, at each site. In zonal soils, sulphate accumulated deeper in the soil profile and declined logarithmically with distance from the southern coast. In recent soils there was little accumulation in the profile. Rainfall sulphur is the most likely source of the reserves. Magnesium accumulated deep in the profile of inland soils in western transects, suggesting that serpentine rock parent material was its source. Generally, available phosphorus, calcium, potassium, total nitrogen and organic carbon concentrations were greatest in the surface layer of soil and declined with soil depth. However, very high phosphate reserves were present deep in the profile at a few specific inland sites. Short-term sustainable agricultural systems could involve the utilisation of at least some of these reserves. This would require the encouragement of deeper-rooting of plants than currently occurs under pastoral systems. Keywords magnesium, nutrient reserves, phosphorus, Southland, sulphate, sustainable agriculture, transects

2021 ◽  
Author(s):  
Mengjiao Sun ◽  
Enqing Hou ◽  
Jiasen Wu ◽  
Jianqin Huang ◽  
Xingzhao Huang

Abstract Background: Soil nutrients play critical roles in regulating and improving the sustainable development of economic forests. Consequently, an elucidation of the spatial patterns and drivers of soil nutrients in these forests is fundamental to their management. For this study, we collected 314 composite soils at a 0-30 cm depth from a typical hickory plantation in Lin 'an, Zhejiang Province, China. We determined the concentrations of macronutrients (i.e., soil organic carbon, hydrolyzed nitrogen, available phosphorus, and available potassium) and micronutrients (i.e., iron, manganese, zinc, and copper.) of the soils. We employed random forest analysis to quantify the relative importance of soil-forming factors to predict the soil nutrient concentrations, which could then be extrapolated to the entire hickory region. Results: Random forest models explained 61%–88% of the variations in soil nutrient concentrations. The mean annual temperature and mean annual precipitation were the most important predictor of soil macronutrient and micronutrient concentrations. Moreover, parent material was another key predictor of soil available phosphorus and micronutrient concentrations. Mapping results demonstrated the importance of climate in controlling the spatial distribution of soil nutrient concentrations at finer scales, as well as the effect of parent material, topography, stand structure, and management measures of hickory plantations. Conclusions: Our study highlights the biotic factors, abiotic factors, and management factors control over soil macronutrient and micronutrient concentrations, which have significant implications for the sustainability of soil nutrients in forest plantations.


2021 ◽  
Author(s):  
Jianwu LI ◽  
Jinlin Yang ◽  
Ganlin Zhang

Abstract Soil is important contributor to global biogeochemical cycles and often receives anthropogenic Pb contamination. Hainan soil chronosequence developed on basalt had provided a good opportunity to identify and quantify the relative contributions of Pb sources in remote tropical areas. The results revealed that Pb concentrations and isotopic ratios of the soils were clearly affected by anthropogenic source. The Pb concentrations and percentage changes of Pb/Th ratios showed significantly Pb enrichment. The low 206Pb/207Pb values of upper soils indicated a significant addition of extraneous Pb, whereas deeper soils showed a dominantly basaltic source. The 208Pb/206Pb vs. 206Pb/207Pb diagram of soils clearly indicated inputs of parent material and anthropogenic Pb sources. We also calculated the mass fractions of anthropogenic-derived Pb (ƒPbanthropogenic) based on isotope mass balance. The ƒPbanthropogenic values showed a generally decreasing trend with soil depth, implying a significant addition of anthropogenic Pb in top soils. The contribution of anthropogenic Pb in Hainan soil chronosequence highlighted the significance of anthropogenic contamination to soils globally.


2017 ◽  
Vol 9 (5) ◽  
pp. 83
Author(s):  
Ngowari Jaja ◽  
Monday Mbila ◽  
Yong Wang

Silvicultural thinning and burning are common management practices that are widely used to address ecosystem problems such as tree stocking and general forest health. However, high-severity fire has variable effects on soils, resulting in damages which are directly or indirectly reflected on the trace metal chemistry of the soil. This study was conducted to evaluate the trace metal variation at the Bankhead National Forest in Northern Alabama following the silvicultural thinning and burning. The experimental site had treatments consisting of two burning patterns and three levels of thinning as part of an overall treatment of three burning patterns and three levels of thinning applied to nine treatment plots to fit a completely randomized block design experiment. Four treatments sites were used for this study and samples were collected from soil profile pits excavated at representative plots within each treatment. The samples were analyzed for trace metals-As, Cu, Ni, Zn and Pb-using Perkin Elmer 2100 ICP-OES. Post treatment samples indicated that the trace metal concentrations generally decreased with soil depth. Copper, Ni, and Zn at the Pre-burn site gradually increased with depth to a maximum concentration at about 50 cm below the soil surface. Arsenic in the surface horizons increased by 156% in the burn-only sites, 54% in the thin-only treatment, 30% for the burn and thin treatments. Such differences were unlikely due to differences in the geochemistry of the parent material, but likely due to anthropogenic activities and possibly the forest management practices in question.


Author(s):  
G. O. Ateh ◽  
M. G. Saka ◽  
E. E. Dishan ◽  
B. B. Meer

This study evaluated the relationship between selected physicochemical properties and microbial populations of the soil of Bagale Forest Reserve, Girei Local Government Area of Adamawa State, Nigeria. Five plots of 20 x 20 m were laid. Soil samples were collected from five different positions at two soil depths of 0-15 cm and 15-30 cm. The soil samples were isolated in the laboratory for microbial populations and determination of physical and chemical properties. The results obtained revealed that fungal population (7.65 x 105 cfu/ml) was the highest at the soil depth of 0-15 cm, representing 39% of the total microbial populations in the sampled soil of the study area. The results further revealed that the population (6.84 x 105 cfu/ml) of the bacteria had a positive effect on soils of the study area in terms of nitrogen fixation by Rhizobacterial spp. Chemical properties of the soil samples revealed that the available phosphorus exhibited the highest percentage (61.7%) at 0-15 cm soil depth. Analyses of soil physical properties recorded the highest percentage (49.0%) of sand at 0-15 cm soil depth. A similar percentage (50.0%) of sand was exhibited at the depth of 15-30 cm. These percentages accounted for the high porosity (29.0%) of the soil observed at the two soil levels in the study area and could be improved through the application of lime fertilizers. Application of appropriate fertilizers like NPK to improve the soil condition of the study area is highly recommended.


2020 ◽  
Vol 09 (04) ◽  
pp. 400-409
Author(s):  
Chinonso Millicent Chris-Emenyonu ◽  
Emmanuel Uzoma Onweremadu ◽  
John Didacus Njoku ◽  
Chioma Mildred Ahukaemere ◽  
Benarden Ngozi Aririguzo

2016 ◽  
Vol 5 (2) ◽  
pp. 57 ◽  
Author(s):  
Nahusenay Abate ◽  
Kibebew Kibret

The study was conducted to investigate the effects of land use, depth and topography on soil physicochemical properties at the Wadla Delanta Massif, northcentral Ethiopia. Four land uses (natural forest, shrub, grazing and cultivated land), three soil depths (0-20, 20-40, 40-60 cm) and three topographic positions (upper, middle and lower) in three replications were considered for this study. A total of 108 composite samples were collected for laboratory analysis. The results show that particle size distribution was affected by the main effects of land use and soil depth; bulk and particle densities, total porosity, organic matter and total nitrogen contents, C:N ratio and available phosphorus were significantly affected by the interaction of land use by soil depth only, whereas, soil pH, electrical conductivity, exchangeable bases, cation exchange capacity, percent base saturation and extractable micronutrients were affected by the interaction effects of the three factors. Highest clay and bulk density were recorded at the bottom layer of the cultivated land soils, while the utmost porosity, organic matter and nitrogen contents, and available phosphorus were recorded at the surface layers of the natural forest land soils. Highest pH was at the bottom layer of the cultivated land at the three topographic positions. Highest exchangeable bases and cation exchange capacity were observed in the bottom layers of soils under the four land use types at the lower topographic position, whilst extractable micronutrients were recorded at the surface layers of the forest land soils at the upper topographic position. In general, most of the measured soil properties were measured better in forest than in other land use soils and the lower topographic positions than the upper and middle ones. Interaction of land use with topography showed negative effects especially on cultivated and grazing land soils in all topographic positions. Therefore, integrated soil fertility management and soil conservation measures are required in all topographic positions to maintain soil physicochemical properties.


2015 ◽  
Vol 24 (1) ◽  
pp. 41-46
Author(s):  
M. Maharjan ◽  
K. D. Awasthi ◽  
K. R. Pande ◽  
N. Thapa

The study aimed at assessing the nutrient status of rangeland in upper Mustang. The assessment is necessary to know about the soil quality or productivity of soil of rangeland. Livestock rearing is one of the main occupations in upper Mustang but nowadays due to lack of palatable species for livestock, people are leaving the occupation which is directly affecting their livelihood status. Therefore this research was carried out to find out if the soil nutrient is the reason behind the lack of availability of palatable species in the rangeland. For soil sampling, north and south aspects were taken. In case of altitude, 3850 m, 3650 m and 3450 m were taken. Soil samples were taken from soil profile up to 60cm depth at interval of 20 cm. Available phosphorus and available potassium were found to be high at north aspect but total nitrogen was found to be high at south aspect. Both total nitrogen and available phosphorus were found to be high at 3650 m. Available potassium was gradually decreased with increasing altitude. Total nitrogen, available potassium and available phosphorus were gradually decreased with increasing soil depth. Nutrient status was high at top soil (0-20 cm).The soil nutrient (Nitrogen, Phosphorus, Potassium) status was found to be good in the study area. Further research on biophysical and ecological aspect of Rangeland in Upper Mustang is necessary to manage it properly.Banko Janakari, Vol. 24, No. 1, PP. 41-46


2020 ◽  
Vol 96 (12) ◽  
Author(s):  
Silvia Garaycochea ◽  
Héctor Romero ◽  
Elena Beyhaut ◽  
Andrew L Neal ◽  
Nora Altier

ABSTRACT Soil microbial communities play critical roles in maintaining natural ecosystems such as the Campos biome grasslands of southern South America. These grasslands are characterized by a high diversity of soils, low available phosphorus (P) and limited water holding capacity. This work aimed to describe prokaryotic communities associated with different soil types and to examine the relationship among these soil communities, the parent material and the soil nutrient status. Five Uruguayan soils with different parent material and nutrient status, under natural grasslands, were compared. The structure and diversity of prokaryotic communities were characterized by sequencing 16S rRNA gene amplicons. Proteobacteria, Actinobacteria, Firmicutes,Verrucomicrobia, Acidobacteria, Planctomycetes and Chloroflexi were the predominant phyla. Ordination based on several distance measures was able to discriminate clearly between communities associated with different soil types. Edge-PCA phylogeny-sensitive ordination and differential relative abundance analyses identified Archaea and the bacterial phyla Firmicutes, Acidobacteria, Actinobacteria and Verrucomicrobia as those with significant differences among soil types. Canonical analysis of principal coordinates identified porosity, clay content, available P, soil organic carbon and water holding capacity as the main variables contributing to determine the characteristic prokaryotic communities of each soil type.


2020 ◽  
Vol 30 (1) ◽  
pp. 39-48
Author(s):  
B. Gautam ◽  
M. K. Chettri

Information on soil properties with regards to forest soil-depth are important for sustainable management of forest. The present study investigated the physicochemical properties of the top soil (0−30cm depth) in the three forests, viz. i) the Terai Shorea Forest (Bardia National Park), ii) the Evergreen Riverine Forest (Bardia National Park) and iii) the Puraina CF (Kailali district) of western Nepal. In the tropical forests of western Nepal, the soil texture is, moreover, loamy sand to sand. The soil bulk density ranged from 1.33−1.63 gm cm-3, and slightly increased with the increase in the soil-depth. The soil pH value ranged from 5.77−7.36. The soil organic carbon, total nitrogen (N), available phosphorus (P), and available potassium (K) were found to be in the ranges of 0.54−1.64%, 0.04−0.14%, 4.84−31.72 kg ha-1, and 204.35−557.44 kg ha-1, respectively, and all these values decreased with the increase in the soil-depth in both the forests of the protected area; however, this decreasing trend of the soil nutrients with the increase in the soil-depth was not observed in the Puraina CF as the values of the soil nutrients were lower within 0−10cm in the CF. The soil nutrients with all the depths were found to be the highest in the Terai Shorea Forest. The lower values of the soil nutrients in the Puraina CF were the result of resource extraction.  


2021 ◽  
Vol 14 (1) ◽  
pp. 29
Author(s):  
Salwinder Singh Dhaliwal ◽  
Vivek Sharma ◽  
Janpriya Kaur ◽  
Arvind Kumar Shukla ◽  
Akbar Hossain ◽  
...  

The agricultural production in Punjab has increased manifold that aggravated the deficiencies of micronutrients in soils and plants. The availability of soil micronutrients in different soil orders depends upon the soil mineralogy, topography, climatic conditions and cropping sequences. Hence, to study the pedospheric variations of DTPA-extractable micronutrients, viz., zinc (Zn), iron (Fe), manganese (Mn) and copper (Cu), in three prominent soil orders of Punjab, a total of 144 depth-wise soil samples were collected from four major land-use systems (cultivated, horticulture, forest and pasture lands). The DTPA extractable micronutrients varied from 1.74–2.81, 1.83–2.82 and 1.81–2.80 for Zn; 5.3–6.8, 5.6–6.9, 4.3–6.3 for Fe; 5.1–7.8, 5.5–7.9, 5.4–7.5 for Mn; and 0.84–1.40, 0.93–1.68, 0.87–1.65 for Cu in soil orders Aridisol, Entisol and Inceptisol, respectively. The average content of DTPA-extractable micronutrients was highest under soil order Entisol followed by Inceptisol and Aridisol. The content of micronutrients showed a declining trend with increase in soil depth in all orders. Among different soil properties, the pH and EC showed significantly negative correlation, however, OC had non-significant correlation with DTPA-extractable micronutrients in soils. Therefore, it is concluded that parent material, land use systems and soil depth affected the distribution of DTPA extractable micronutrients in different soil orders.


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