摘要
三七（Panax notoginseng（Burk.）F.H.Chen）是云南文山州的道地中药材,文山州由于地壳原始分化成分的作用和含砷矿的开采等原因,使三七种植区存在普遍的土壤砷污染现象。通过野外大田调查和室内分析相结合的方法,研究了云南文山三七主要种植区（文山县、丘北县、砚山县、广南县）土壤总砷和有效砷的空间分布特征和土壤物理化学特征（pH值、有机质含量、阳离子交换量CEC、总P、速效P、土壤质地）,探讨了三七不同部位（茎叶、花果、主根、须根、剪口）As含量的影响因素。将有助于了解文山三七种植区砷污染空间分布特点,寻求三七砷含量的调控途径,对降低三七砷含量和提高三七品质具有一定的实践和理论意义。研究结果表明,（1）土壤有效As和总As平均质量分数分别为0.29 mg·kg-1和28.51mg·kg-1,土壤有效As占总As质量分数的0.06%~2.08%。76.67%的土壤样品总As含量达到国家土壤环境质量的二级标准。土壤有效As和总As含量空间分布表现出西北高,东南低的趋势。（2）三七各部位中As质量分数为0.14~0.32 mg·kg-1,砷含量符合优质三七砷的限量标准（≤1.0 mg·kg-1）,三七各部位对As的富集系数为0.004~0.011,均较低。（3）90%的土壤为酸性土壤,pH值≤6.5;土壤全P质量分数为1.27 g·kg-1,土壤速效P质量分数为66.87 mg·kg-1,均属于丰富水平;土壤有机质质量分数为15.77 g·kg-1,CEC为26.74 cmol·kg-1,属于较高水平;40%的土壤为黏土,43.4%为壤质黏土。（4）土壤总As和土壤有效As含量主要受到随机人为因素的影响,表现出与土壤CEC、pH值和有机质含量之间显著的正相关关系。三七须根中As含量与土壤总As、有效As、土壤黏粒含量、CEC、pH值和总P含量之间具有显著的正相关性。总之,壤质黏土、低pH值和CEC有利于降低三七As含量,三七种植过程中应避免施用含As有机肥和磷肥。研究结果在系统
Panax notoginseng （Burk.） F.H. Chen is one of traditional Chinese medicinal materials in Wenshan Prefecture, Yunnan Province. Soil As contamination exists in P. notoginseng plantation area due to parent rocks weathering and As mining. Field investigation and lab analysis were conducted in order to understand As spatial distribution and physical and chemical characteristics （pH value, organic matter content, CEC, total P content, available P content and soil texture） of soil and its effects on As contents in different parts （stem/leaves, flower/fruits, main root, fibrous root and rhizome） of Panax notoginseng in P. notoginseng plantation area in Wenshan Prefecture （Wenshan county, Qiubei county, Yanshan county and Guangnan county）, Yunnan Province, China. This research would contribute to understand the spatial distribution of soil As contents in P. notoginseng plantation area and seek the control methods to reduce As contents in P. notoginseng, which are of important practice and theoretical roles on reducing As contents in P. notoginseng and improving quality of P. notoginseng. The results showed that： （1） The contents of total As and available As were 0.29 mg·kg-1 and 28.51 mg·kg-1, respectively. The available As content occupied 0.06%-2.08%of total As. Some 76.67%of soil samplings were met with the secondary standard value of national soil environmental quality. The spatial distribution of total As and available As contents showed the tendency of high in north-western and low in south-eastern of P. notoginseng plantation area in Wenshan Prefecture. （2） The As contents in different parts of P. notoginseng were 0.14-0.32 mg·kg-1, which was according with the limitation standard of As for high quality of P. notoginseng. The accumulation coefficient of As in different parts of P. notoginseng was 0.004-0.011. （3） Some 90% of samples were acid soil with pH ≤6.5. Soil total P and available P contents were 1.27 g·kg-1 and 66.87 mg·kg-1, respectively, which were belong to abundant l
出处
《生态环境学报》
CSCD
北大核心
2014年第6期1034-1041,共8页
Ecology and Environmental Sciences
基金
国家自然科学基金项目(41261096)
关键词
三七
空间分布
理化性质
AS
Panax notoginseng
spatial distribution
physical and chemical characteristics
As
