Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 10 of 10
Full-Text Articles in Physical Sciences and Mathematics
Impacts Of Stress On Forest Recovery And Its Interaction With Canopy Height, Peipei Xu, Tao Zhou, Chuixiang Yi, Hui Luo, Xiang Zhao, Wei Fang, Shan Gao, Xia Liu
Impacts Of Stress On Forest Recovery And Its Interaction With Canopy Height, Peipei Xu, Tao Zhou, Chuixiang Yi, Hui Luo, Xiang Zhao, Wei Fang, Shan Gao, Xia Liu
Publications and Research
Global climate change is leading to an increase in the frequency, intensity, and duration of drought events, which can affect the functioning of forest ecosystems. Because human activities such as afforestation and forest attributes such as canopy height may exhibit considerable spatial differences, such differences may alter the recovery paths of drought-impacted forests. To accurately assess how climate affects forest recovery, a quantitative evaluation on the effects of forest attributes and their possible interaction with the intensity of water stress is required. Here, forest recovery following extreme drought events was analyzed for Yunnan Province, southwest China. The variation in the …
Separation Of Soil Evaporation And Vegetation Transpiration By Modis Data For Central And Northern China, Tingting Li, Jinhui Jeanne Huang
Separation Of Soil Evaporation And Vegetation Transpiration By Modis Data For Central And Northern China, Tingting Li, Jinhui Jeanne Huang
International Conference on Hydroinformatics
Evapotranspiration(ET) plays a crucial role in the hydrologic system. To estimate evapotranspiration quantitatively in a large scale, remote sensing data has been used in a number of models and shows its applicability in the estimation of evapotranspiration. In this paper, evapotranspiration for central and northern China was derived from MODIS data. In arid and semi-arid regions, soil evaporation can be considered as the minimum water requirement for bare area, while evapotranspiration can be considered as the minimum water demand for the area covered by vegetation. Hence the separation of soil evaporation and vegetation transpiration is valuable for efficient water resources …
Moving Horizon Estimation To Assimilate Snow And Soil Moisture Data Into The Hbv Hydrological Model, Rodolfo Alvarado Montero, Dirk Schwanenberg, Peter Krahe, Aynur Şensoy
Moving Horizon Estimation To Assimilate Snow And Soil Moisture Data Into The Hbv Hydrological Model, Rodolfo Alvarado Montero, Dirk Schwanenberg, Peter Krahe, Aynur Şensoy
International Conference on Hydroinformatics
We present a variational data assimilation approach based on a Moving Horizon Estimation (MHE) applied to the HBV hydrological model. This framework enables the modification of the model inputs precipitation and temperature as well as the model states soil moisture, upper zone storage and lower zone storage. It considers data products for snow cover, snow water equivalent and soil moisture and observed streamflow. The performance of the framework is evaluated for three test sites: i) the data–dense catchment of the upper Main River (2419 km2), Germany, for which the HBV model already produces excellent results, ii) a comparable upstream catchment …
Graphic User Interface To Preprocess Landsat Tm, Etm+ And Oli Images For Hydrological Applications, Rafael Pimentel, Javier Herrero, María José Polo
Graphic User Interface To Preprocess Landsat Tm, Etm+ And Oli Images For Hydrological Applications, Rafael Pimentel, Javier Herrero, María José Polo
International Conference on Hydroinformatics
Remote sensing techniques are powerful tools for the validation and data assimilation of GIS-based calculations of physical and distributed hydrological models. The high spatial resolution of Landsat TM, ETM+ and OLI, make this the most adequate satellite images for the study of hydrological processes in Mediterranean regions. Several levels of preprocessing are required to obtain validated reflectance values from these images. Generally, these steps include radiometric calibrations and an atmospheric correction. However, over complex terrain and for specific land covers such as snow, certain problems related to radiometric saturation and shadow effects must also be taken into account. This work …
Research And Application On The Coupled Method Of Remote-Sensing And Ground-Monitoring Of Reservoir Storage Capacity, He Zhu, Hongli Zhao, Yunzhong Jiang, Li Wang
Research And Application On The Coupled Method Of Remote-Sensing And Ground-Monitoring Of Reservoir Storage Capacity, He Zhu, Hongli Zhao, Yunzhong Jiang, Li Wang
International Conference on Hydroinformatics
Reservoir storage capacity monitoring is the basis of reservoir operation. The relationship curves of reservoir water level-area and water level-capacity are the significant parameters of storage capacity calculation. With the long-term operation, both on the bottom and bank of the reservoir have erosion and deposition, causing the relationship of water level-area and level-storage changes, which leads to inaccuracy of reservoir storage capacity calculation with the original curves. It is costly to revise the curves of reservoir water level-area and water level-capacity by ground measurement termly. A coupled Method of Remote-sensing and Ground-monitoring of Reservoir Storage Capacity is proposed in this …
Automated Meter Reading For Water Demand Forecast And Hydraulic Modelling Of The Municipal Water Distribution System In Mikołów, Poland, Patryk Wójtowicz, Andrzej Pawlak, Jan Studziński
Automated Meter Reading For Water Demand Forecast And Hydraulic Modelling Of The Municipal Water Distribution System In Mikołów, Poland, Patryk Wójtowicz, Andrzej Pawlak, Jan Studziński
International Conference on Hydroinformatics
This paper presents preliminary results of a project aimed at utilising automated meter reading (AMR) system for water demand forecasting and hydraulic modelling of Mikołów (Poland) water distribution system. This system will allow for near-real time collection of hydraulic data. Accurate estimation and prediction of the demand patterns of the customers is a crucial element affecting accuracy of hydraulic model. AMR will be used to analyse the behaviour of individual household-based water consumption. Calibration and validation of the model will be realised by combining existing SCADA system and mobile (temporary) measurement points. Total length of the main water distribution system …
Empirical Regression Model Using Ndvi, Meteorological Factors For Estimation Of Wheat Yield In Yunnan, China, Jing Huang, Qiang Dai, Huimin Wang, Dawei Han
Empirical Regression Model Using Ndvi, Meteorological Factors For Estimation Of Wheat Yield In Yunnan, China, Jing Huang, Qiang Dai, Huimin Wang, Dawei Han
International Conference on Hydroinformatics
Crop yield estimation is of great importance to food security. NDVI, as an effective crop monitoring tool, is extensively used in crop yield estimation. However there are few studies conducted in the regions where mixed crops are grown. In this study, a statistical approach for crop area identification is proposed and applied to wheat in Jianshui County in the Nanpan River Basin, Yunnan Province of China. Based on the correlation analysis between MODIS NDVI data and crop yield, the planting areas are identified, as well as the best periods for a reliable estimation. Regression models are presented to predict the …
On The Importance Of Remote Sensing Data To Validate A Distributed Dynamic Vegetation Model Applied To A Semi-Arid Basin, Félix Francés, Guiomar Ruiz-Pérez, Marta Pasquato, Chiara Medici, María González-Sanchis, Tarcísio J. G. Fernandes, Antonio Molina, Antonio D. Del Campo
On The Importance Of Remote Sensing Data To Validate A Distributed Dynamic Vegetation Model Applied To A Semi-Arid Basin, Félix Francés, Guiomar Ruiz-Pérez, Marta Pasquato, Chiara Medici, María González-Sanchis, Tarcísio J. G. Fernandes, Antonio Molina, Antonio D. Del Campo
International Conference on Hydroinformatics
Efforts to better understand the components of catchments’ water balance have traditionally been one of the objectives of the hydrological community. Very few hydrological models incorporate vegetation development as state variable. This is beginning to change with the recognition by the hydrological community that biological processes play a key role in catchment’s water balance. In addition, some studies confirm that vegetation density controls most of hydrological processes in semi-arid regions. However, the most of the dynamic vegetation models are too complex to be coupled with hydrological models and they incorporate variables and inputs which are difficult to be estimated across …
Monitoring Spatiotemporal Total Organic Carbon Concentrations In Lake Mead With Integrated Data Fusion And Mining (Idfm) Technique, Sanaz Imen, Ni-Bin Chang, Y. Jeffrey Yang
Monitoring Spatiotemporal Total Organic Carbon Concentrations In Lake Mead With Integrated Data Fusion And Mining (Idfm) Technique, Sanaz Imen, Ni-Bin Chang, Y. Jeffrey Yang
International Conference on Hydroinformatics
Forest fires, soil erosion, and land use changes in Lake Mead watershed nearby Las Vegas wash are considered as sources of water quality impairment in the Lake Mead. These conditions result in higher concentration of Total Organic Carbon (TOC). TOC in contact with Chlorine which is often used for disinfection purposes of drinking water supply causes the formation of trihalomethanes (THMs). THM is one of the toxic carcinogens controlled by EPA’s Disinfection By-Product Rule. As a result of threat posed to drinking water of 25 million people downstream, recreation area, and wildlife habitat of Lake Mead, it is necessary to …
Precipitation Forecasting With Wavelet-Based Empirical Orthogonal Function And Artificial Neural Network (Weof-Ann) Model, Sanaz Imen, Ni-Bin Chang, Y. Jeffrey Yang
Precipitation Forecasting With Wavelet-Based Empirical Orthogonal Function And Artificial Neural Network (Weof-Ann) Model, Sanaz Imen, Ni-Bin Chang, Y. Jeffrey Yang
International Conference on Hydroinformatics
Western drought began since 2000 caused sharp decrease by about 100 feet in the largest reservoir of North America, Lake Mead due to the precipitation pattern shift in the upstream lower Virgin River Basin. Oceans play an important role on earth’s climate via oceanic-atmospheric interactions known as climate teleconnections, which deeply affect the terrestrial precipitation patterns. This issue signifies the necessity of developing a modern hydroinformatics tool - precipitation forecasting model - to account for teleconnection signals from climate change and mitigate drought hazards impact on lake water, quantitatively and qualitatively, which cannot be achieved by using traditional Global Circulation …