Phosphorus fractions and phosphomonoesterase activities in sandy soils under a temperate savanna and a neighboring Mongolian pine plantation
Qiong Zhao , De-hui Zeng
Journal of Forestry Research ›› 2006, Vol. 17 ›› Issue (1) : 25 -30.
Phosphorus fractions and phosphomonoesterase activities in sandy soils under a temperate savanna and a neighboring Mongolian pine plantation
To assess the effects of savanna afforestation on soil phosphorus (P) transformations in eastern Horqin Sandy Land, China, P fractions and phosphomonoesterase activities were examined in two soil horizons (0–5 cm and 5–20 cm) under a savanna and an adjacent 30-year-old Mongolian pine (Pinus sylvestris L. var. mongolica Litv.) plantation on a P-deficient semi-arid sandy soil. The results showed that all soil P fractions and phosphomonoesterase activities decreased with soil depth at both sites except that labile organic P under the plantation was constant with soil depth. In contrast to savanna, soils under Mongolian pine plantation had lower phosphomonoesterase activities and concentrations of all P fractions (with an exception of Al-P), lower proportions of organic P and Ca-P in total P, and higher proportions of labile P, Al-P and Fe-P in total P. These results suggested that P transformations mainly occurred in surface soils, and P recycled through litter-fall was the most important source of plant available P. Mongolian pine afforestation enhanced the bioavailability of both organic P and Ca-P, simultaneously reduced soil P pools, indicating that protection of forest floor and P fertilization are necessary to maintain the sustainable functioning of Mongolian pine plantations.
Afforestation / P fractions / P bioavailability / Phosphomonoesterase activity / Sandy soil
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| [2] |
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| [3] |
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| [4] |
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| [5] |
|
| [6] |
|
| [7] |
|
| [8] |
|
| [9] |
|
| [10] |
|
| [11] |
|
| [12] |
|
| [13] |
|
| [14] |
|
| [15] |
|
| [16] |
|
| [17] |
|
| [18] |
|
| [19] |
|
| [20] |
|
| [21] |
|
| [22] |
|
| [23] |
|
| [24] |
|
| [25] |
|
| [26] |
|
| [27] |
|
| [28] |
|
| [29] |
|
| [30] |
|
| [31] |
|
| [32] |
|
| [33] |
|
| [34] |
|
| [35] |
|
| [36] |
|
| [37] |
|
| [38] |
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