南京大学学报（自然科学版）Issue(6)：1279-1290,12.DOI:10.13232/j.cnki.jnju.2015.06.025
分形入渗下非饱和饱和系统中水流的时空变化
The temporospatial variations of water flow in an unsaturated-saturated system under infiltrations of fractional Gaussian noise and fractional Brownian motion
摘要
Abstract
The damping effect of an unsaturated-saturated system (USS)on the fluctuations of water flow and the effect of the scaling exponent of infiltration (β)on the damping effect were investigated.The moment equations of the pressure head (ψ)were solved numerically to obtain the variance ofψat 7 observation points.Power spectrum ofψ(Sψψ)were estimated by directly solving the equations of the unsaturated-saturated system.Results show that USS filters out the short-term fluctuations ofψ,so the fluctuations ofψare weakened and the short-term correlation increases.The damping effect decreases with depth and should be soil moisture dependent.The damping effect decreases with the increase of the value ofβ.The fluctuations ofψare first non-stationary and finally stationary under the infiltration of fractional Gaussian noise and the larger the value ofβ,the longer the non-stationary period.The fluctuations ofψare non-stationary all the time under the infiltration of fractional Brownian motion and the larger the value ofβ,the stronger the non-stationarity.The temporal scaling is an important factor inducing the scaling of temporal fluctuations of groundwater levels.关键词
阻尼作用/非饱和饱和系统/时间尺度性/分形/分数高斯噪声/分数布朗运动Key words
damping effect/unsaturated-saturated system/temporal scaling/fractal/fractional Gaussian noise/fractional Brownian motion分类
天文与地球科学引用本文复制引用
杨晨,张幼宽,梁修雨..分形入渗下非饱和饱和系统中水流的时空变化[J].南京大学学报（自然科学版）,2015,(6):1279-1290,12.基金项目
国家自然科学基金(41272260,41330314,41302180),江苏省自然科学基金(SBK201341336) （41272260,41330314,41302180）
