期刊
ENVIRONMENT INTERNATIONAL
卷 133, 期 -, 页码 -出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.envint.2019.105159
关键词
Paddy soil; Arsenic; Flooding; Mobilization; Native hygrophyte
资金
- National key R&D Program of China [2016YFD0200900]
- National Natural Science Foundation of China [41977108]
- Hunan Young Talents Supporting Program [2017RS3032]
- Agricultural Innovation Project of Hunan Province [2019TD01]
- Special Funds for Local Science and Technology Development Guided by the Central Committee [2017XF5039]
- Hunan Provincial Education Department
China ranks the top in global annual rice output. However, extensive mining and smelting has led to elevated arsenic (As) in paddy soils, potentially imperiling local population health and sustainable rice production in the country. Under flooded condition, reductive As mobilization generally occurs, providing a unique advantage for soil As removal. In this study, we explore the depletion magnitude of labile As from paddy soils through cycling of flooding-drainage with three distinct co-strategies, i.e. (1) no soil disturbance with spontaneously established hygrophyte plants, (2) selective fertilization to enhance soil As release, and (3) soil ploughing following each drainage. After 151 days of flooding with periodic drainage, diffusive gradients in thin film (DGT)-labile As through 0-14 cm soil profile with hygrophyte plants growing decreased from initial 292 mu g l(-1) to well below the required threshold level (57-77 mu g l(-1)) for safe rice production. Correspondingly, an average of 22.9% of total soil As was removed, with up to 76.7% of As bound to amorphous Fe hydroxides being stripped in this treatment. In the following rice cultivation, inorganic As in the polished rice from the naturally vegetated treatment (0.15 mg kg(-1)) fell successfully below the Chinese food safety standard (0.2 mg kg(-1)). The results highlight that As removal from paddy soils with native hygrophyte under shallow flooded condition can decrease soil bioavailable As specifically to safe levels within a relatively short period, and thus provides a novel and quite cost-effective pathway securing rice production.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据