CAJ | 학술논문

采用物理改良措施覆沙和底质疏松,对南四湖湿地沉积物-水微界面氧化还原状况及间隙水营养盐垂向分布特征的影响进行了研究.结果表明,改良措施能够有效地改善沉积物的物理结构及氧气的垂向分布.在沉积物-水界面附近,覆沙和底质疏松均能显著提高界面处氧化层的厚度,覆沙效果最佳.随着剖面深度的增加,间隙水中NH_4~+和可溶性PO_4~(3-)浓度呈指数关系增长,改良措施能有效降低间隙水中PO_4~(3-)的含量,轻度底质疏松的效果最佳,差异显著(P(0.05).而界面以下NO_3~-和氧气浓度呈指数关系下降,在沉积物中10cm以下时营养盐接近一个常数,在4mm以下溶解氧接近0.对剖面沉积物不同形态的磷组分进行统计检验表明,改良措施能有效提高表层沉积物中NH_4Cl-P及BD-P(铁磷)的含量.
채용물리개량조시복사화저질소송,대남사호습지침적물-수미계면양화환원상황급간극수영양염수향분포특정적영향진행료연구.결과표명,개량조시능구유효지개선침적물적물리결구급양기적수향분포.재침적물-수계면부근,복사화저질소송균능현저제고계면처양화층적후도,복사효과최가.수착부면심도적증가,간극수중NH_4~+화가용성PO_4~(3-)농도정지수관계증장,개량조시능유효강저간극수중PO_4~(3-)적함량,경도저질소송적효과최가,차이현저(P(0.05).이계면이하NO_3~-화양기농도정지수관계하강,재침적물중10cm이하시영양염접근일개상수,재4mm이하용해양접근0.대부면침적물불동형태적린조분진행통계검험표명,개량조시능유효제고표층침적물중NH_4Cl-P급BD-P(철린)적함량.
Investigation was carried out to evaluate the impact of physical amelioration treatments (fine sand covered and sediment loosened) on the sediments and pore water in Lake Nansi wetland in China. Oxygen microprofiles near sediment-water interface and the vertical distribution of pore-water nutrients (PO_4~(3-), NH_4~+, NO_3~- and NO_2~- ) in the uppermost sediment were determined. The treatments could effectively improve sediment physical structure (i.e. water content, porosity et al.) and oxygen depth-distribution. The oxic zone thickness at sediment-overlying water interface was significantly widened in fine sand covered and loosened sediments treatments compared with those in-situ sediments treatment(P <0.05), and the oxygen furthermost penetrations were determined in fine-sand covered treatment. The NH_4~+ and PO_4~(3-) distribution in the vertical profile exhibited a nearly exponential increase and a NO_3~- decrease with depth in 10 cm surface sediment, indicating an approximate constant concentration below 10 cm depth. Otherwise, dissolved oxygen sharply deceased with depth at the water-sediment surface and arrived near zero mg/L at the 4 mm depth. All treatments could decrease PO_4~(3-) concentration in pore water, and the lowest interstitial PO_4~(3-) concentration was found in slightly loosened sediment treatments (P <0.05). Also, NH_4Cl-extractable PO_4~(3-) and bicarbonate dithionite (BD)-extractable PO_4~(3-) contents increased significantly in slightly loosened sediment treatment, especially in surface.