昌黎生态监控区无机N、P 变化及潜在性富营养化评价

对2006—2010年每年8月河北昌黎生态监控区测定的无机N(NO2-N、NO3-N、NH4-N)和无机P(PO4-P)含量,进行多年站位及总量分析,揭示其年际变化趋势,并结合海水质量标准进行潜在性富营养化评价。结果表明:无机N总量(DIN)于前4年持续下降,而2010年急剧上升至历年最高水平,其中NO3-N含量总体水平远高于NO2-N和NH4-N,成为DIN主要组成部分;无机P含量则呈波动性上升趋势。潜在性富营养化评价结果显示,2010年19个站位均为P限制潜在性富营养(ⅥP),其他年份仅个别站位呈N或P限制潜在性富营养(ⅤN或ⅥP)及中度营养(Ⅱ),其余均为贫营养(Ⅰ)。

Variation of inorganic nitrogen and inorganic phosphorus andpotential eutrophication assessment in ecology-monitoring area of Changli

In order to reveale the inter-annual variation trends,this paper proceeds stations and total analysis with inorganic nitrogen(NO2-N、NO3-N、NH4-N) content and inorganic phosphorus(PO4-P) content in ecology-monitoring area of Changli in Hebei province on August each year from 2006 to 2010.And we combine with sea water quality standards for potential eutrophication assessment.The analysis results show that: inorganic nitrogen total content(DIN) had continued to decline for the first 4 years,but it has rapidly rose to a record high level in 2010.Among them,the overall level of NO3-N content is far higher than NO2-N content and NH4-N content,becomes a major component of DIN,and inorganic phosphorus content presents the volatility of the rising trend.The results of the potential eutrophication assessment show that: the nutrient levels of 19 stations are P limited potential eutrophication(ⅥP) in 2010,other years of the individual stations are N or P limited potential eutrophication(ⅤN or ⅥP) and moderate nutrition(Ⅱ),and others are poor nutrition(Ⅰ).This paper has important practical significance that we can improve marine water quality conditions and rational use of marine resources.