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A Probabilistic process-based model of Bank Erosion and Its Application in the Middle Yangtze River

JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE 2025年第1期130卷

作者： Zhu, Heng Xia, Junqiang Deng, Shanshan Zhou, Yueyao Wuhan Univ State Key Lab Water Resources Engn & Management Wuhan Peoples R China

Bank erosion in a natural alluvial river is influenced not only by near-bank hydraulic conditions but also predominantly by bank soil properties. These factors exhibit considerable uncertainties, which are seldom considered in previous bank erosion models. Therefore, this study proposes a probabilistic process-based model of bank erosion by embedding the probability distributions of different bank soil parameters. The model was applied to simulate the bank erosion process in the Middle Yangtze River (MYR), and it was validated against field measurements. Results show that: (a) bank soil parameters including critical shear stress, friction angle and cohesion, followed the Log-Normal or Gamma distribution, with large variation coefficients of 0.44, 0.59, and 0.50;(b) the expected values of the calculated bank erosion widths agreed closely with measurements (with a relative error of 5%), and the high probability of mass failure occurred within a seasonal timescale (during September-November 2019), despite the high uncertainties in soil properties;and (c) the incorporation of water content variation into the stochastic model further increased the uncertainty of the results by several-fold, indicating that considering more influencing factors in the model may reduce prediction accuracy. Besides, from a large-scale perspective, the high diversity of river morphology (channel width) is also closely related to these uncertainties.

关键词： river bank erosion process-based model probability analysis groundwater level Middle Yangtze River

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How can the parameterization of a process-based model help us understand real tree-ring growth?

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TREES-STRUCTURE AND FUNCTION 2019年第2期33卷 345-357页

作者： Tychkov, Ivan I. Sviderskaya, Irina V. Babushkina, Elena A. Popkova, Margarita I. Vaganov, Eugene A. Shishov, Vladimir V. Siberian Fed Univ L Prushinskoi St 2 Krasnoyarsk 660075 Russia Siberian Fed Univ Khakas Tech Inst Shetinkin Str 27 Abakan 655017 Russia Le Studium Loire Valley Inst Adv Studies 1 Rue Duponloup F-45000 Orleans France

Key messageThis study shows great potential of the well-validated VS-Oscilloscope (a visual accurate parameterization of the VS-model) for assessment of spatial-temporal cambium phenology, which is illustrated based on the analysis of comprehensive datasets from central ***-growth response to changing climate varies depending on tree species, forest type, and geographical region. process-based models can help us better understand and anticipate these outcomes. To characterize growth sensitivity to different climate parameters, we applied the VS-Oscilloscope analytical package, as a precise visual parameterization tool of the Vaganov-Shashkin model, to two contrasting habitats: one with tree-ring growth limitation by soil moisture (in the southern part of central Siberia) and the another with temperature limitation (in the middle part of central Siberia). We speculate that specific parameter values of the Vaganov-Shashkin model and their variability under local conditions and species are the key to understand different physiological processes in conifers. According to the simulation results for the temperature-limited site, wider rings of Picea obovata can result from a longer growing season. However, for the soil moisture-limited site, the final sizes of the tree rings of Pinus sylvestris were not affected by the length of the growing season but were primarily defined by the intra-seasonal variations in soil moisture, even under cold conditions. For the two sites, we obtained a 20-day difference between the two phenological dates, in which the early date could be associated with cambial initiation and the late date with the appearance of the first enlarging cell. In the case of central Siberia, the time period was half that of the southern Siberia. Such differences could be explained by both geography and species-specific responses to phenology. To test this hypothesis, additional tree-ring and climatic data for contrasted habitats would be needed.

关键词： process-based model VS-oscilloscope Parameterization Growing season Climate signal Tree-ring seasonal variability

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A process-based model for estimating the well-to-tank cost of gasoline and diesel in China

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APPLIED ENERGY 2013年第Feb.期102卷 718-725页

作者： Li, Weiqi Fu, Feng Ma, Linwei Liu, Pei Li, Zheng Dai, Yaping Beijing Inst Technol Sch Automat Beijing 100081 Peoples R China Tsinghua Univ Dept Thermal Engn State Key Lab Power Syst Tsinghua BP Clean Energy Ctr Beijing 100084 Peoples R China

In this paper, we present a process-based model to estimate the well-to-tank (WTT) costs of vehicle fuels (gasoline and diesel). The model breaks down the WTT process into four stages, i.e., crude oil sourcing (import and extraction), crude oil transportation, crude oil refining, and vehicle fuel transportation and distribution, which can provide high-resolution data for the WTT cost components. Using this model, we further develop an empirical study of China. The results obtained from the study indicate that the price of imported crude oil is the dominant factor affecting the WTT costs of vehicle fuels in China and that the cost of crude oil refining also has a relatively large influence. By comparing the costs with the prices of vehicle fuels under the volatile price of imported crude oil, we illustrate the unstable margin caused by China's current pricing policy, which causes a distorted price signal and fiscal risks. The key findings derived from the empirical study reveal that the WIT cost is an essential guide for altering the vehicle fuel price with the aim of not only smoothing the impacts caused by the volatile price of crude oil price but also reflecting the correct oil price signal and reducing the fiscal risks. (c) 2012 Elsevier Ltd. All rights reserved.

关键词： process-based model Well-to-tank cost Vehicle fuel China

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Riparian vegetation dynamics: insight provided by a process-based model, a statistical model and field data

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ECOHYDROLOGY 2013年第4期6卷 567-585页

作者： Ye, F. Chen, Q. Blanckaert, K. Ma, J. Chinese Acad Sci Res Ctr Ecoenvironm Sci RCEES State Key Lab Urban & Reg Ecol Beijing 10085 Peoples R China China Three Gorges Univ Yichang 443002 Peoples R China Leibniz Inst Freshwater Ecol & Inland Fisheries I Dept Limnol Shallow Lakes & Lowland Rivers Berlin Germany

The dynamics of riparian vegetation in a reach of the Lijiang River, China, are investigated. A new process-based model is developed based on cellular automata, which simulates the key processes in the life cycle of the ten most occurring plant species: germination, normal growth, response to floods and droughts, destruction by high velocities, consumption of resources, colonization and competition. The parameterization of these processes is based on controlled experiments on plants sampled in the study area. A traditional statistical model is also developed, which relates the vegetation state to four flow-related variables. Both models are assessed based on data from 12 field surveys in the period from 2009 to 2011, during the dry season, the wet season and at the end of the growing season. Both models predict satisfactorily the spatial distribution of the vegetation cover at the end of the growing season. Although the statistical model is by definition limited to the steady state conditions at the end of the growing season, the process-based model also satisfactorily simulates the temporal dynamics of the vegetation during the dry season and the wet season. Contrary to the statistical model, the process-based model also satisfactorily simulates the vegetation cover outside the area used for the model parameterization. Thus, process-based models are more robust under flow regimes with spatial heterogeneity and important temporal variations. Field observations and process-based model predictions indicate that the regime of dry season and wet season floods is the main regulator of the vegetation cover in the study area. Copyright (C) 2012 John Wiley & Sons, Ltd.

关键词： riparian vegetation process-based model statistical model field data flow model

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Significance of rainfall distribution in predicting eucalypt plantation growth, management options, and risk assessment using the process-based model CABALA

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FOREST ECOLOGY AND MANAGEMENT 2004年第1-2期193卷 283-296页

作者： Mummery, D Battaglia, M Cooperat Res Ctr Sustainable Prod Forestry Hobart Tas 7001 Australia CSIRO Forestry & Forest Prod Hobart Tas 7001 Australia Univ Tasmania Sch Geog & Environm Studies Hobart Tas 7001 Australia

In the past, criteria for site selection for plantations of Eucalyptus globulus have focused on the expected yield predicted using long-term average climate data. When selecting sites using predictive models of plantation growth, scant consideration has been given to climatic variation and how this affects the probability that droughts will reduce yield or cause death of trees. This is often because either the time step of the models does not provide the required resolution, or because climatic data of the required resolution is not available. In particular, rainfall patterns are often represented simplistically. In this work we generate daily rainfall patterns with different methods (observed sequences, naive daily distribution of monthly rainfall totals, and simulation of daily rainfall using a Markov rainfall intensity and dry spell simulator) and use these as input sequences into the process-based tree-growth model CABALA [For. Ecol. Manage., this volume]. We examine how rainfall representation influences prediction of growth and the development of water stress in modelled plantations and compare predictions of growth, pre-dawn soil-water potential and aspects of nitrogen uptake and utilisation with observations made over a rainfall gradient in southwest Western Australia. The naive rainfall representation led to biased predictions, failed to represent the soil-water recharge benefit of high intensity rainfall events, under predicted tree drought stress, and failed to adequately represent nitrogen leaching and conditions for nitrogen mineralisation in plantation soils. Furthermore, it was clear from the distribution of plantation yields that were predicted using observed weather sequences that appropriate evaluation of plantation risk requires the representation of rainfall in a way that captures inter-annual variability in rainfall amount. We concluded that if we are to obtain maximum benefit from the application of process-based models it is necessary that inp

关键词： process-based model Eucalyptus globulus Markov rainfall model rainfall representation drought death

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Application of a process-based model for predicting the productivity of Eucalyptus nitens bioenergy plantations in Spain

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GLOBAL CHANGE BIOLOGY BIOENERGY 2016年第1期8卷 194-210页

作者： Gonzalez-Garcia, Marta Almeida, Auro C. Hevia, Andrea Majada, Juan Beadle, Chris Finca Expt La Mata Forest & Wood Technol Res Ctr CETEMAS Grado 33820 Spain CSIRO Land & Water Flagship Hobart Tas 7001 Australia Univ Tasmania Tasmanian Inst Agr Hobart Tas 7001 Australia

The feasibility of using plantation-grown biomass to fuel bioenergy plants is in part dependent on the ability to predict the capacity of surrounding forests to maintain a sustainable supply. In this study, the potential productivity of Eucalyptus nitens (Deane and Maiden) Maiden plantations grown for bioenergy in a region of north-west Spain was quantified using the 3-PG process-based model. The model was calibrated using detailed measurements from five permanent sample plots and validated using data from thirty-five additional permanent sample plots;both sets represented the variability of climate and soils of the region. Plot scale analysis showed that the model was able to reasonably estimate above-ground biomass and water use when compared with the observed data. Using a representative loam soil characteristic, a spatial analysis was then carried out to predict the potential productivity of E. nitens for bioenergy across a potential area for plantation establishment of 2550 km(2) and to evaluate different management scenarios related to rotation length and stocking. An increase of only 1.9% in mean annual increment (MAI) of above-ground biomass (W-AGB) was found between stockings of 3000 and 5000 trees ha(-1);for the lower stocking, MAI of W-AGB increased 4% for rotation lengths between 6 and 8 years. Production was reduced by low summer rainfall and to a lesser extent by high summer and low winter temperatures, and vapour pressure deficit. Above-ground biomass production was higher by around 12% when average rather than actual climate data were applied. The information from this study can be used to optimize forest management, determine regional relative potential productivity and contribute to decision-making for bioenergy production from E. nitens plantations in north-west Spain.

关键词： 3-PG model bioenergy biomass production Eucalyptus geographic information system potential productivity process-based model short-rotation woody crops spatial analysis

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Estimation of maize yield by using a process-based model and remote sensing data in the Northeast China Plain

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PHYSICS AND CHEMISTRY OF THE EARTH 2015年 87-88卷 142-152页

作者： Yao, Fengmei Tang, Yanjing Wang, Peijuan Zhang, Jiahua Univ Chinese Acad Sci Key Lab Computat Geodynam Beijing 100049 Peoples R China Chinese Acad Meteorol Sci Inst Ecoenvironm & Agrometeorol Beijing 100081 Peoples R China Chinese Acad Sci Key Lab Digital Earth Sci Inst Remote Sensing & Digital Earth Beijing 100094 Peoples R China Yangtze Univ Coll Geosci Wuhan 430100 Peoples R China

Climate change significantly impact on agriculture in recent year, the accurate estimation of crop yield is of great importance for the food security. In this study, a process-based mechanism model was modified to estimate yield of C-4 crop by modifying the carbon metabolic pathway in the photosynthesis sub-module of the RS-P-YEC (Remote-Sensing-Photosynthesis-Yield estimation for Crops) model. The yield was calculated by multiplying net primary productivity (NPP) and the harvest index (HI) derived from the ratio of grain to stalk yield. The modified RS-P-YEC model was used to simulate maize yield in the Northeast China Plain during the period 2002-2011. The 111 statistical data of maize yield from study area was used to validate the simulated results at county-level. The results showed that the Pearson correlation coefficient (R) was 0.827 (p < 0.01) between the simulated yield and the statistical data, and the root mean square error (RMSE) was 712 kg/ha with a relative error (RE) of 9.3%. From 2002 to 2011, the yield of maize planting zone in the Northeast China Plain was increasing with smaller coefficient of variation (CV). The spatial pattern of simulated maize yield was consistent with the actual distribution in the Northeast China Plain, with an increasing trend from the northeast to the southwest. Hence the results demonstrated that the modified process-based model coupled with remote sensing data was suitable for yield prediction of maize in the Northeast China Plain at the spatial scale. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： process-based model Maize Crop yield C-4 crop Remote sensing Northeast China Plain

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Using a process-based model to understand dynamics of Chinese agricultural and water technology development from 8000 bc to 1911 ad

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AMBIO 2021年第5期50卷 1101-1116页

作者： Wu, Shuanglei Wei, Yongping Head, Brian Zhao, Yan Hanna, Scott Univ Queensland Sch Earth & Environm Sci Brisbane Qld 4072 Australia Univ Queensland Fac Humanities & Social Sci Ctr Policy Futures Brisbane Qld 4072 Australia Univ Queensland Ctr Crop Sci Queensland Alliance Agr & Food Innovat Brisbane Qld 4072 Australia

Advancements in technology are inextricably bound to our society and the natural environment. However, how the development process of a technology system interacts with both remains unclear. We propose a process model to understand the complex dynamics among technology, society, and the environment via seven interactive elements: technologies, actors, receiving bodies, natural contexts, social contexts, temporal-spatial contexts, and outcomes. The model was applied to agricultural and water technology development in China from 8000 bc to 1911 ad. Our findings show that these elements did not play equally important roles in different periods of the development in ancient China, with social contexts most dominating during the earlier periods and both social and environmental concerns arising towards the later periods. The proposed model, by identifying the elements in the technology development that should be strengthened, can act as an analysis device to assist in reconfiguring a more sustainable socio-technological system.

关键词： Agricultural and water technology development Ancient china process-based model Socio-technological dynamics

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Description and test of a simple process-based model of forest growth for mixed-species stands

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ECOLOGICAL modelLING 2007年第3-4期203卷 297-311页

作者： Duursma, R. A. Marshall, J. D. Robinson, A. P. Pangle, R. E. Univ Idaho Dept Forest Resources Moscow ID 83844 USA

process-based models of forest growth have been discussed for decades, but their utility as management tools has only recently begun to increase. Ideally this type of model would be tested by treating it as a complex hypothesis that relates independently measured parameters to predicted responses. This approach provides a test of the structure and the parameterization of the model that is not possible if the model has been calibrated (or tuned). We conduct such a test of a new model of forest production and allocation. The test uses a series of plots located across complex terrain in northern Idaho, USA. The production model scales leaf-level gas exchange to the canopy, and is parameterized with foliar nitrogen, leaf area index (LAI), and canopy structural parameters. New biomass is allocated such that tree allometry is maintained while foliage and branches turn over. A simple approach combines allometric equations across species in mixed-species stands. Predictions of volume increment for a 10-year period were higher than measurements, but the two were significantly correlated. The discrepancy was reduced when leaf area index was estimated from canopy light transmission rather than allometric equations. We argue that one likely reason for the overprediction is the occurrence of soil water deficits in the summer. A sensitivity analysis showed that estimates of production were most sensitive to leaf area index and canopy average foliar nitrogen content, but much less to other parameters. We conclude that comparing the model to observed data reveals shortcomings that might have been hidden if the parameters had been tuned. The mixed-species allometric constraint provides a new tool for modeling biomass allocation in mixed-species stands. (C) 2006 Elsevier B.V. All rights reserved.

关键词： forest productivity mixed-species stands biomass allocation process-based model

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Reproduction of estuarine bathymetry by means of a process-based model: Western Scheldt case study, the Netherlands

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GEOMORPHOLOGY 2012年 179卷 152-167页

作者： van der Wegen, M. Roelvink, J. A. UNESCO IHE NL-2601 DA Delft Netherlands Deltares NL-2600 MH Delft Netherlands Delft Univ Technol NL-2600 GA Delft Netherlands

The current study aims to investigate the processes governing the evolution of major morphological features in alluvial estuaries as well as their morphodynamic interaction with the geometry by means of a 3D morphodynamic, process-based numerical model (Delft3D). The main hypothesis is that channel-shoal patterns evolve through the interaction between tidal movement, the available sediments and the tidal basins' geometry. Once such a system is not disturbed too much by extreme events, stable morphological patterns will emerge that compare well with observed features. Starting from a flat bed and imposing the Western Scheldt geometry, model results show two distinct time-scales, i.e. channel-shoal pattern formation within decades and a slow longitudinal profile development continuing for centuries. The developing channel-shoal patterns reflect major morphological features observed in the Western Scheldt estuary. Using the 1998 bathymetry as a reference, we applied different indicators and techniques to evaluate the model performance over time, namely: visual comparison, hypsometries, Brier Skill Score (BSS), mean basin depth and longitudinal profiles. Sensitivity analysis shows that trends in development are similar for different model parameter settings, like introducing salt-fresh water density differences or variations in sediment grain size and sediment transport formulation. Varying river discharge and including non-erodible layers, dredging and dumping activities and 3D hydrodynamics led to occasional improvements. The geometry is an important governing factor for pattern development. Applying an erodible geometry reveals a timescale for geometric adaptation that is much longer than the pattern development timescale within the basin. model runs including highly schematized extreme conditions suggest that extreme events play a limited role. The main conclusion of the study is that the interaction between tidal forcing and basin geometry plays a major role in the

关键词： Coastal geomorphology Morphodynamic modeling process-based model Estuarine morphology Channel-shoal pattern formation

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