基于PEST的土壤水力參數(shù)數(shù)值反演研究
本文關(guān)鍵詞: 土壤水力參數(shù) SWAP模型 PEST 土壤含水量 實(shí)際蒸散發(fā) 出處:《中國地質(zhì)大學(xué)(北京)》2017年碩士論文 論文類型:學(xué)位論文
【摘要】:土壤水力參數(shù)的確定是農(nóng)業(yè)水文模型應(yīng)用的重要環(huán)節(jié)。近年來,數(shù)值反演方法被廣泛的應(yīng)用于土壤水力參數(shù)的估計(jì)。該方法雖然避免了人工試錯(cuò)法的費(fèi)時(shí)費(fèi)力,但也存在著局部收斂和“異參同效”等問題,獲得的結(jié)果的準(zhǔn)確性仍然存在爭議。因此,研究土壤水力參數(shù)的數(shù)值反演,多方面的對(duì)優(yōu)化的參數(shù)以及模擬結(jié)果進(jìn)行評(píng)估,對(duì)數(shù)值反演方法的應(yīng)用以及模型精度的提高具有重要意義。本文將農(nóng)業(yè)水文模型SWAP(Soil-Water-Atmosphere and Plant)與數(shù)值反演程序PEST耦合,利用北京市通州區(qū)張家灣試驗(yàn)站的三個(gè)土壤剖面,首先進(jìn)行SWAP模型的正向模擬,得到土壤含水量和實(shí)際蒸散發(fā)值,將這些值作為實(shí)際觀測(cè)值并認(rèn)為沒有誤差,用于反演模擬。其次,本文探討了數(shù)值反演的單一目標(biāo)優(yōu)化。從土壤含水量觀測(cè)誤差,觀測(cè)頻率和觀測(cè)點(diǎn)空間設(shè)置三個(gè)方面對(duì)估計(jì)參數(shù)的不確定性和模擬結(jié)果進(jìn)行評(píng)估。結(jié)果表明,當(dāng)只用土壤含水量來反演估計(jì)土壤水力參數(shù)時(shí),土壤含水量觀測(cè)誤差應(yīng)在37.5%以內(nèi),且土壤水力參數(shù)的不確定性隨著土壤水分觀測(cè)誤差的增加而增加;土壤水力參數(shù)的反演對(duì)觀測(cè)頻率變化不敏感,土壤含水量的觀測(cè)頻率最好不要超過四周;觀測(cè)點(diǎn)的增加對(duì)土壤含水量的擬合精度有所提高,當(dāng)每層各增加一個(gè)點(diǎn)時(shí),模擬結(jié)果最好,但如果條件不允許時(shí),在第一層加觀測(cè)點(diǎn),對(duì)各層反演精度的提高貢獻(xiàn)更大。在此基礎(chǔ)上,考慮到單一變量的不可靠性,我們進(jìn)一步探索數(shù)值反演的多目標(biāo)優(yōu)化。本文在應(yīng)用土壤含水量的基礎(chǔ)上,增加實(shí)際蒸散發(fā)量(ETa)作為另一反演變量,比較了在不同作物體系下,分別用土壤含水量(θ)、土壤含水量和實(shí)際蒸散發(fā)量(ETa)、實(shí)際蒸散發(fā)量(ETa)反演得到的各反演變量的模擬結(jié)果。結(jié)果表明,在假設(shè)的現(xiàn)實(shí)條件下(土壤含水量觀測(cè)誤差為10%,觀測(cè)頻率為一周,觀測(cè)點(diǎn)為每個(gè)土壤層一個(gè)),只用ETa反演得到的結(jié)果均是最差的,尤其是對(duì)于土壤含水量的模擬;ETa的加入對(duì)反演變量模擬精度的提高并不明顯,甚至在輪作時(shí),會(huì)有反作用,這說明,在大多數(shù)情況下,只用土壤含水量進(jìn)行參數(shù)反演就足夠了,ETa對(duì)于土壤含水量和ETa的擬合效果的提高并沒有太大作用。
[Abstract]:The determination of soil hydraulic parameters is an important step in the application of agricultural hydrological models. In recent years, numerical inversion method has been widely used in the estimation of soil hydraulic parameters. However, there are also some problems such as local convergence and "heteroparametric equivalence", and the accuracy of the obtained results is still controversial. Therefore, the numerical inversion of soil hydraulic parameters is studied, and the optimized parameters and simulation results are evaluated in many aspects. It is of great significance for the application of numerical inversion method and the improvement of model precision. In this paper, the agricultural hydrological model SWAP(Soil-Water-Atmosphere and plant is coupled with the numerical inversion program PEST, and the three soil sections of Zhangjiawan Experimental Station in Tongzhou District, Beijing, are used in this paper. First, the forward simulation of the SWAP model is carried out to get the soil moisture content and the actual evapotranspiration value. These values are regarded as the actual observed values and there is no error, so they can be used to inverse the simulation. In this paper, the single objective optimization of numerical inversion is discussed. The uncertainty and simulation results of the estimated parameters are evaluated from three aspects: the observation error of soil moisture content, the observation frequency and the space setting of observation points. When only soil water content is used to estimate soil hydraulic parameters, the observation error of soil water content should be less than 37.5%, and the uncertainty of soil hydraulic parameters increases with the increase of soil moisture observation error. The inversion of soil hydraulic parameters is insensitive to the change of observed frequency, and the observation frequency of soil water content should not exceed four weeks, and the fitting accuracy of soil water content is improved with the increase of observation points, when one point is added to each layer, The simulation results are the best, but if conditions do not permit, adding observation points in the first layer contributes more to the improvement of inversion accuracy in each layer. On this basis, considering the unreliability of a single variable, We further explore the multi-objective optimization of numerical inversion. Based on the soil moisture content, the increase of actual evapotranspiration (ETa) is used as another inversion variable to compare different crop systems. The simulated results obtained from the inversion of soil water content (胃), soil moisture content and actual evapotranspiration (ETaan) and actual evapotranspiration (ETaa) are obtained respectively. In the hypothetical realistic condition (the observation error of soil water content is 10, the observation frequency is one week, the observation point is one for each soil layer, the results obtained by ETa inversion are the worst. In particular, the addition of ETa to the simulation of soil moisture content does not improve the simulation accuracy of the inversion variables obviously, even in rotation, which indicates that, in most cases, Only soil water content can be used for parameter inversion is enough to improve the fitting effect of soil water content and ETa.
【學(xué)位授予單位】:中國地質(zhì)大學(xué)(北京)
【學(xué)位級(jí)別】:碩士
【學(xué)位授予年份】:2017
【分類號(hào)】:S152.7
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 宋曉猛;占車生;夏軍;;集成統(tǒng)計(jì)仿真技術(shù)和SCE-UA方法的水文模型參數(shù)優(yōu)化[J];科學(xué)通報(bào);2012年26期
2 徐旭;屈忠義;黃冠華;;基于遺傳算法的田間尺度土壤水力參數(shù)與溶質(zhì)運(yùn)移參數(shù)優(yōu)化[J];水利學(xué)報(bào);2012年07期
3 馮紹元;馬英;霍再林;宋獻(xiàn)方;;非充分灌溉條件下農(nóng)田水分轉(zhuǎn)化SWAP模擬[J];農(nóng)業(yè)工程學(xué)報(bào);2012年04期
4 查元源;周發(fā)超;楊金忠;;一種由土壤剖面含水率估算土壤水力參數(shù)的方法[J];水利學(xué)報(bào);2011年08期
5 江思珉;朱國榮;施小清;周念清;;水文地質(zhì)參數(shù)反演的Hooke-Jeeves粒子群混合算法[J];水科學(xué)進(jìn)展;2010年05期
6 劉路廣;崔遠(yuǎn)來;馮躍華;;基于SWAP和MODFLOW模型的引黃灌區(qū)用水管理策略[J];農(nóng)業(yè)工程學(xué)報(bào);2010年04期
7 郭云慧;李紅華;魚京善;;北京市通州區(qū)水環(huán)境規(guī)劃方案下的水質(zhì)模擬研究[J];北京師范大學(xué)學(xué)報(bào)(自然科學(xué)版);2009年Z1期
8 夏軍;張永勇;王中根;李浩;;城市化地區(qū)水資源承載力研究[J];水利學(xué)報(bào);2006年12期
9 江東,王建華,楊小喚,王乃斌,Rosema A;黃河流域主要水文參數(shù)遙感反演[J];水科學(xué)進(jìn)展;2003年06期
10 李國芳,夏自強(qiáng),郝振純,蔣洪庚,陳海芳;田間土壤含水率的變異性及監(jiān)測(cè)誤差分析[J];水科學(xué)進(jìn)展;2000年04期
相關(guān)博士學(xué)位論文 前2條
1 楊樹青;基于Visual-MODFLOW和SWAP耦合模型干旱區(qū)微咸水灌溉的水—土環(huán)境效應(yīng)預(yù)測(cè)研究[D];內(nèi)蒙古農(nóng)業(yè)大學(xué);2005年
2 魏占民;干旱區(qū)作物—水分關(guān)系與田間灌溉水有效性的SWAP模型模擬研究[D];內(nèi)蒙古農(nóng)業(yè)大學(xué);2003年
相關(guān)碩士學(xué)位論文 前5條
1 李彥;節(jié)水灌溉條件下河套灌區(qū)土壤水鹽動(dòng)態(tài)的SWAP模型分布式模擬預(yù)測(cè)[D];內(nèi)蒙古農(nóng)業(yè)大學(xué);2012年
2 羅治勇;農(nóng)田水分動(dòng)態(tài)模擬研究[D];長安大學(xué);2008年
3 何錦;基于SWAP模型的農(nóng)田水分動(dòng)態(tài)模擬研究[D];長安大學(xué);2006年
4 欒承梅;流域水文模型參數(shù)優(yōu)化問題研究[D];河海大學(xué);2005年
5 任志遠(yuǎn);北京市平原區(qū)地下水資源研究[D];吉林大學(xué);2004年
,本文編號(hào):1485583
本文鏈接:http://sikaile.net/kejilunwen/nykj/1485583.html