地球化学
地毬化學
지구화학
GEOCHIMICA
2014年
4期
346-351
,共6页
磷%Hedley分级%吸附%解吸%黄河三角洲
燐%Hedley分級%吸附%解吸%黃河三角洲
린%Hedley분급%흡부%해흡%황하삼각주
phosphorus%Hedley fractionation%adsorption%desorption%Yellow River Delta
采用改进的 Hedley 磷分级方法研究了黄河三角洲新生湿地由河向海过渡带表层土壤磷形态变化和分布特征，并通过等温吸附解吸实验阐明了沿程土壤对外源磷的持留能力和释放风险。结果表明，各样点无机磷占总磷93%以上，是磷的主要存在形态。土壤中有机磷含量较低，可能与较低的有机质含量有关。无机磷中稀盐酸磷是最主要存在形态，与各样点Ca/Al含量密切相关。有效磷含量在18.6~33.4 mg/kg之间，仅占总磷的3.2%~5.9%，可能会限制湿地植物的生长。覆有植被的土壤中有效磷含量显著高于河滩和海滩土壤，说明植被存在对有效磷的积累有一定促进作用。由吸附解吸实验可知，加入较低浓度(0.05~5 mg/L)的外源磷时，随着初始磷浓度的升高，土壤对磷的吸附量增加，吸附率为70%~99%，解吸率小于7%，这说明各样点土壤的除磷能力较强，且流失风险较低。
採用改進的 Hedley 燐分級方法研究瞭黃河三角洲新生濕地由河嚮海過渡帶錶層土壤燐形態變化和分佈特徵，併通過等溫吸附解吸實驗闡明瞭沿程土壤對外源燐的持留能力和釋放風險。結果錶明，各樣點無機燐佔總燐93%以上，是燐的主要存在形態。土壤中有機燐含量較低，可能與較低的有機質含量有關。無機燐中稀鹽痠燐是最主要存在形態，與各樣點Ca/Al含量密切相關。有效燐含量在18.6~33.4 mg/kg之間，僅佔總燐的3.2%~5.9%，可能會限製濕地植物的生長。覆有植被的土壤中有效燐含量顯著高于河灘和海灘土壤，說明植被存在對有效燐的積纍有一定促進作用。由吸附解吸實驗可知，加入較低濃度(0.05~5 mg/L)的外源燐時，隨著初始燐濃度的升高，土壤對燐的吸附量增加，吸附率為70%~99%，解吸率小于7%，這說明各樣點土壤的除燐能力較彊，且流失風險較低。
채용개진적 Hedley 린분급방법연구료황하삼각주신생습지유하향해과도대표층토양린형태변화화분포특정，병통과등온흡부해흡실험천명료연정토양대외원린적지류능력화석방풍험。결과표명，각양점무궤린점총린93%이상，시린적주요존재형태。토양중유궤린함량교저，가능여교저적유궤질함량유관。무궤린중희염산린시최주요존재형태，여각양점Ca/Al함량밀절상관。유효린함량재18.6~33.4 mg/kg지간，부점총린적3.2%~5.9%，가능회한제습지식물적생장。복유식피적토양중유효린함량현저고우하탄화해탄토양，설명식피존재대유효린적적루유일정촉진작용。유흡부해흡실험가지，가입교저농도(0.05~5 mg/L)적외원린시，수착초시린농도적승고，토양대린적흡부량증가，흡부솔위70%~99%，해흡솔소우7%，저설명각양점토양적제린능력교강，차류실풍험교저。
A modified Hedley phosphorus (P) fractionation was used to study the P distribution seaward in the newly formed wetlands soils of Yellow River Delta. In addition, the adsorption-desorption experiments were performed to evaluate the ability of P retention and release in the sampled soils. The results showed that inorganic P remained the largest portion of total P (TP), accounting for more than 93% of TP. Due to the lower content of organic matter, the organic P was relatively low in these soils. Among the inorganic P, Dilute HCl-P was the dominated form, related with the content of Ca in soils. The content of available P was 18.6~33.4 mg/kg, accounting for only 3.2%~5.9% of TP in soils, which might restrict the growth of plants in the wetland system. Furthermore, it was found that the content of available P in the sampling site covered with plants was higher than that in the beach soils, indicating that the vegetation cover may enhance the accumulation of soil available P. According to the adsorption-desorption experiments, when the concentration of initial P addition was in the range of 0.05~5 mg/L, the P adsorption increased with the increase of initial P concentration. Moreover, the percentage of adsorption was 70%~99%while desorption rate was less than 7%. It could be concluded that in these soils, the capacity of P retention was high and the release potential was relatively low.
