Considerations on representative water quality data
Considerations on representative water quality data
复制标题
对代表性水质数据的考虑
DOI：
--
复制
发表时间：
1992
期刊：
影响因子：
--
通讯作者：
L. Håkanson
中科院分区：
文献类型：
--
作者：
L. Håkanson
本文的目的是给一个简短的总结有关的重要方法方面，在建立经验水质数据的可靠性。这些考虑与应用工作有关，例如监测方案，以及理论研究，例如验证模型。该文件涉及瑞典湖泊中关于梭子鱼、鲈鱼、水和沉积物中汞含量的数据，以及一系列广泛的湖沼学数据（pH值、Secchi深度、温度、碱度、总磷、电导率、铁、钙、硬度、叶绿素a和颜色）。这些标准参数一般在一个湖泊中变化，在时间上和区域上。本文的重点是这种变化和如何表达湖泊典型值。不同参数的分析可靠性有很大差异;例如，汞（鱼和沉积物中，但不是水中）和湖泊pH值通常可以以相对较高的准确度测定; pH值的平均相对标准偏差（V）仅约为2-3%。在天然湖泊中，对于颜色、磷、铁和碱度等参数，变异性通常至少是“方法学”变异性的两倍（在我们的湖泊中，V值平均在20%至40%之间）。这意味着，对于大多数参数，必须分析许多样本，以获得具有代表性的，具有一定统计可靠性的湖泊典型值。一个一般的furmula表示需要多少样本来建立湖泊典型的平均值进行了讨论，以及统计方面的经验数据的模型的基础上，这些数据的范围。
The aim of this paper is to give a brief summary concerning important methodological aspects in establishing the reliability of empirical water quality data. These considerations are relevant for applied work e.g. monitoring programmes, as well as theoretical research, e.g. to validate models. The paper concerns data from Swedish lakes on Hg in pike, perch, water and sediments, and a broad set of limnological data (pH, Secchi depth, temperature, alkalinity, total-P, conductivity, Fe, Ca, hardness, chlorophyll-a and colour). These standard parameters generally vary in a lake, both temporally and areally. The focus of this paper is on such variations and how to express lake-typical values. There are large differences in analytical reliability for different parametres; e.g. Hg (in fish and sediments but not in water) and lake pH can generally be determined with a comparatively great accuracy; the average relative standard deviation (V) is only about 2-3% for pH. Colour, Fe-, total-P-concentration and alkalinity, on the other hand, generally give high V-values. In natural lakes, the variability is often at least twice as large as the “methodological” variability for parameters such as colour, P, Fe and alkalinity (V-values ranging between 20 and 40% on average in our lakes). This implies that for most parameters one must analyse many samples to obtain representative, lake-typical values with a given statistical reliability. A general furmula expressing how many samples are required to establish lake-typical mean values is discussed as well as statistical aspects concerning the range of empirical data in models based on such data.