کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6408498 1629456 2015 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Incremental acidification reveals phosphorus release dynamics in alkaline vertic soils
ترجمه فارسی عنوان
اسیدی شدن افزایشی نشان دهنده دینامیک انتشار فسفر در خاک های قلیایی است
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
چکیده انگلیسی


- Alkaline Vertisols release P at threshold acidic pH values.
- With no root analogue solubilised P increased 82-181% near pH 5.
- With a root analogue (exchange membrane) solubilised P increased 112-160% near pH 6.
- Rhizosphere acidification may release significant P in alkaline Vertisols.

Phosphorus (P) available to plants in alkaline, vertic soils is thought to be buffered by the dissolution of various calcium phosphate minerals (CaP), driven by pH and the concentration of Ca and/or P in solution. To investigate this hypothesis we incrementally acidified 6 alkaline vertic soils of CaP 300-6000 mg kg− 1 in the presence or absence of an anion exchange P sink. Following the early removal of solution and sorbed P sources, P recovery remained low until soil pH passed key thresholds. These thresholds varied little between soils and with the sink (pH 6.0-6.3), and soil pH buffer capacity affected the amount of acid required to approach the thresholds. Dissolution of CaP species occurred 0.7-1.0 pH units higher where the solution P concentration was kept below 1 μM using the anion exchange membrane sink compared to acidification without the sink. The data support the hypothesis that rhizosphere acidification may increase the availability of CaP minerals to plants; however, the dependence of P release dynamics on pH buffering capacity may put P release beyond the reach of some plant species. Consequently, research is necessary to quantify both plant acidification potential in these soils and the effect of concomitant removal of Ca on release of CaP species into plant available forms.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Geoderma - Volumes 259–260, December 2015, Pages 35-44
نویسندگان
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