News Update on Calcareous Soil Research: Dec – 2019

Extension of the phosphorus depletion zone in VA-mycorrhizal white clover in a calcareous soil

To examine the influence of vesicular-arbuscular (VA) mycorrhizal fungi on phosphorus (P) depletion within the rhizosphere, mycorrhizal and non-mycorrhizal dutch clover (Trifolium repens L.) were grown for seven weeks during a sterilized calcareous soil in pots with three compartments, a central one for root growth and two outer ones for hyphae growth. Compartmentation was accomplished by a 30-μm nylon net. the basis compartment received a consistent level of P (50 mg kg−1 soil) together with low or high levels of P (50 or 150 mg kg−1 soil) within the hyphal compartments. Plants were inoculated withGlomus mosseae (Nicol. & Gerd.) Gerd. & Trappe or remained uninfected. [1]

Effect of Cement Type on Shear Behavior of Cemented Calcareous Soil

There is little information within the geotechnical literature regarding the influence of the sort of cement on the engineering behavior of cemented soils. This paper explores the mechanical behavior of a calcareous soil under triaxial loading after treatment with differing types of cement, namely hydraulic cement, gypsum, and calcite. to spot the precise effects of every cement A parametric study was undertaken, where factors like density and unconfined compressive strength were maintained constant for every cementing agent. Samples of the cemented soil were examined under optical and microscopy to know the bond mechanism created by each cement. [2]

Enhancement of Phytoextraction of Zn, Cd, and Cu from Calcareous Soil:  The Use of NTA and Sulfur Amendments

In a field experiment we investigated the efficiency of two hyperaccumulating species, four agricultural crop plants, and one woody crop, at phytoextraction of Zn, Cd, and Cu from a polluted calcareous soil. additionally, we examined the likelihood to reinforce the phytoextraction of those metals by application of nitrilotriacetate (NTA) and elemental sulfur (S8) to the soil. Metal uptake by hyperaccumulating species was above that by crop species but was generally low altogether treatments compared to results reported within the literature, maybe as a results of lower total and available soil metal concentrations. Soil amended with either S8 or NTA increased the solubility (NaNO3-extraction) of Zn, Cd, and Cu ions by factors of 21, 58, and 9, respectively, but plant accumulation of those metals was only increased by an element of 2−3. As a result, even the very best metal removal rates achieved during this study were still faraway from what would be required to form this system practicable for the remediation of the Dornach field site. [3]

Effects of the continuous use of organic manure and chemical fertilizer on soil inorganic phosphorus fractions in calcareous soil

A 4-year field trial with three treatments and three sorts of annually rotated vegetables was conducted in calcareous soil during a greenhouse employing a phosphorus (P) fractionation method supported the inorganic P fraction arrangement described by Jiang-Gu. With an equivalent nutrient input, vegetable yields and P uptake were more stable under the chemical fertilizer (CF) treatment than under the organic manure (OM) treatment, and therefore the average utilization rate of P fertilizer (URP) values were 5.27% and 11.40% under the OM and CF treatments, respectively, over the 4 years. [4]

Drain Envelopes for Problematic Calcareous Soils of Irrigated Agricultural Lands in Egypt

Envelope materials are used for surrounding subsurface drain pipes commonly installed to reclaim waterlogged and salt-affected lands to stop entry of soil particles into drains and to constitute a medium of excellent permeability round the pipe and thus reduce entrance resistance. In calcareous soils susceptible to the reduction of drainage capacity as a results of high clogging, determining adequate envelope materials may be a crucial issue under Egyptian conditions. The study was conducted on a calcareous soil with a high risk of carbonate precipitation. Four drain-envelope combinations of subsurface drainage systems were tested in an experimental field. It came out that granular and pre-wrapped drain envelopes, with a traditional grade of 10cm/100m, were the simplest material regarding their hydraulic and mechanical performance for sub-surface drainage in calcareous soils. [5]

Reference

[1] Li, X.L., George, E. and Marschner, H., 1991. Extension of the phosphorus depletion zone in VA-mycorrhizal white clover in a calcareous soil. Plant and Soil, 136(1), (Web Link)

[2] Ismail, M.A., Joer, H.A., Sim, W.H. and Randolph, M.F., 2002. Effect of cement type on shear behavior of cemented calcareous soil. Journal of Geotechnical and Geoenvironmental Engineering, 128(6), (Web Link)

[3] Kayser, A., Wenger, K., Keller, A., Attinger, W., Felix, H.R., Gupta, S.K. and Schulin, R., 2000. Enhancement of phytoextraction of Zn, Cd, and Cu from calcareous soil: the use of NTA and sulfur amendments. Environmental Science & Technology, 34(9), (Web Link)

[4] Effects of the continuous use of organic manure and chemical fertilizer on soil inorganic phosphorus fractions in calcareous soil
Ke Song, Yong Xue, Xianqing Zheng, Weiguang Lv, Hongxia Qiao, Qin Qin & Jianjun Yang
Scientific Reports volume 7, (Web Link)

[5] Sallam, G. (2018) “Drain Envelopes for Problematic Calcareous Soils of Irrigated Agricultural Lands in Egypt”, Journal of Experimental Agriculture International, 20(4), (Web Link)