巢湖十五里河沉积物生物有效性氮磷分布及相关性

摘要

在巢湖十五里河采集15个沉积物柱样,对表层(0～10 cm)沉积物生物有效性氮、磷含量和空间分布特征及相互关系进行研究.结果表明,十五里河表层沉积物的各形态[ IEF(离子交换态),WAEF(弱酸可提取态),SAEF(强碱可提取态)和SOEF(强氧化剂可提取态)]生物有效性氮、磷含量存在较为明显的空间变化性.w(生物有效性氮)占w(TN)的53.4％～ 67.9％,且w(SOEF-N) ＞w(IEF-N) ＞w(SAEF-N) ＞w(WAEF-N),其中w(SOEF-N)为411.35～ 965.47mg/kg,占w(TN)的33.4％～43.7％；w(生物有效性磷)占w(TP)的47.3％～89.4％,且w(SAEF-P)＞w(SOEF-P)＞w(WAEF -P) ＞w(IEF - P),其中w(SAEF-P)为311.74 - 960.33 mg/kg,占w(TP)的33.O％～78.0％.不同形态生物有效性氮的相关性较差,其中w( IEF - N)与w(WAEF-N)和w(SAEF-N)呈负相关,相关系数分别为-0.042和-0.122；w(WAEF-N)和w(SAEF-N)和w(SOEF-N)的相关系数仅为0.320～0.513.生物有效性磷的相关性相对较强,其中w(IEF -P)与w( WAEF - P)呈显著正相关,相关系数为0.527,w(WAEF-P)与w(SAEF-P)呈极显著正相关,相关系数为0.653.不同形态生物有效性氮、磷的相关性不显著.%Fifteen sediment cores were sampled from the representative reaches of the Shiwuli River, Chaohu Lake, and analyzed in order to study the content levels, spatial distribution characteristics and correlation of bio-available nitrogen and phosphorus in the surface sediments (0-10 cm). The results showed that there was significant spatial variability of the content levels of various forms (IEF, WAEF, SAEF and SOEF) of bio-available nitrogen and phosphorus among the fifteen sampling sites. Generally, the four bio-available nitrogen forms comprised S3. 4% to 67. 9% of the total nitrogen ( TN ) , and the content levels followed the sequence: ω(SOEF-N) >ω(IEF-N) >ω(SAEF-N) >ω(WAEF-N), of which the ω(SOEF-N) was 411. 35-965.47 mg/kg with a proportion of 33. 4% -43. 7% . The four bio-available phosphorus forms comprised 47. 3% to 89. 4% of the total phosphorus (TP) , and the content levels followed the sequence:ω( SAEF-P) > ω( SOEF-P) > ω( WAEF-P) > ω( IEF-P) , of which the ω( SAEF-P) was 311. 74-960. 33 mg/kg with a proportion of 33. 0% -78. 0% . There was weak correlation between the four bio-available nitrogen forms. Meanwhile, ω(IEF-N) had negative correlations with ω(WAEF-N) and ω(SAEF-N), with correlation coefficients of -0.042 and -0. 122, respectively. The correlation coefficients between ω(WAEF-N), ω(SAEF-N) and ω(SOEF-N) varied from 0. 32 to 0. 513. However, notable correlations could be found for the bio-available phosphorus forms. In particular, there was significant and positive correlation between ω(IEF-P) and ω( WAEF-P), with correlation coefficient of 0.527, and highly significant correlation between ω(WAEF-P) and ω(SAEF-P) , with correlation coefficient of 0.653. Generally, no significantcorrelations could be found between the four bio-available nitrogen and bio-available phosphorus forms in the sediments of Shiwuli River, Chaohu Lake.