Effects of the Construction of Golf Course on Runoff Characteristics

最近，许多地方政府严格限制建设新的高尔夫球场，因为这会破坏环境。例如，地方政府规定了本地区高尔夫球场的总数和总面积的上限。然而，很难指出这些规定的科学依据。本研究的主要目的是提供评价高尔夫球场建设对区域水文现象影响的方法。本研究分为两个部分。(1)现场观测施工前后的水文现象观测十分重要。从1991年到1993年，我们对新高尔夫球场施工现场的降雨量、排放量、浊度和水质进行了测量。这个高尔夫球场于1992年开始建造，预计于1995年提供服务。现在下结论说这个高尔夫球场对径流特性的影响还为时过早。(2)检测径流特征变化的理论方法——存储函数模型的随机响应——评价径流特征变化是非常困难的，众所周知，所有观测数据都存在一定的误差。即使高尔夫球场建设前后的水文曲线出现了一些变化，我们也必须判断这种变化是真实的还是在误差范围内的。然而，很难估计误差的范围。如果我们提供估计排放量的置信度，这个问题将得到解决。我们必须驱动放电的概率密度函数以获得其置信度。另一方面，储流量关系是检测径流机制变化的直接方法。认为存储模型的随机响应将为上述问题提供解决方案。所有真实的水文过程或多或少都是随机的。虽然径流过程的动力学可以用微分方程来描述，但严格地说，径流现象最好用随机微分方程来表达。随机方程分为三类：1.随机方程；初始条件被描述为随机或概率。微分方程中包含的参数是随机变量。强制项是随机变量。虽然实际的径流现象包括所有三类，但本研究的重点是最后一类，作为第一步。从理论上得到了放电的前四个中心力矩。根据得到的前四个中心矩，可以估计出放电的概率密度函数。结果表明，放电的概率密度函数近似为伽马分布或对数正态分布。少

Recently, many local governments impose severe restrictions on constructing new golf course because they cause destruction of environment. For example, local governments set the upper limit of total number of golf course and its total area within their territory. However, it is difficult to point out scientific justification of these regulations. The main aim of this research provides methods how to evaluate effects of the construction of golf course on regional hydrological phenomena This research consists of two parts.(1) Field observationIt is very important to observe hydrological phenomena before and after the construction. We have measured rainfall, discharge, turbidity and water quality at the construction site of new golf course from 1991 t0 1993. The construction of this golf course began in 1992 and is expected to provide service in 1995. It is too early to conclude effects of this golf course on runoff characteristics.(2) Theoretical approach to detect the change of runoff c … More haracteristics-Stochastic response of storage function model-It is very difficult to evaluate change of runoff characteristics It is well known that all observed data have always some error. Even if hydrograph before and after the construction of golf course shows some change, we have to decide this change is real one or within error. However, it is hard to estimate the range of error. This problem will be solved if we provide the confidence level of estimated discharge. We must drive the probability density function of discharge to obtain its confidence level. On the other hand, the relationship between storage and discharge is a direct method to detect the change of runoff mechanism. It is considered that stochastic response of storage model will provide the solution for above problem.All real hydrologic processes are more or less stochastic. While the dynamics for the runoff process are described by differential equations, strictly speaking, runoff phenomena are best expressed by stochastic differential equations. Stochastic equations are grouped into three classes :1.Initial conditions are described as stochastic or probability.2.The parameters included in differential equations are random variables.3.Forcing terms are random variables.This research focuses on the last class as first step although real runoff phenomena include all three classes. First four central moments of discharge are obtained theoretically. It is possible to estimate the probability density function of discharge based on obtained first four central moments. It is concluded that the probability density function of discharge is approximated by Gamma distribution or log-normal distribution. Less