| Soil moisture means soil water content status, which is an important part of the soil environment, not only an important factor of the soil fertility but also a prerequisite for crop’s growth and development. Soil moisture forecast is the premise and basis of agricultural production, irrigation and water management. Soil moisture changing by a variety of weather factors, as well as by the impact of man-made, crop type, soil type. Simulation and prediction of the soil moisture need to know subside and growth law of soil water. In order to improve water use efficiency, to promote the development of new water-saving irrigation agriculture, to promote traditional agriculture to sustainable modern agriculture. Moisture is now a hot research topic at home and abroad, the core technology of irrigation management system. In order to increase agricultural production and efficient use of water require grasping the dynamic changes of soil moisture in a smaller time and spatial scales, which is particularly important to improve the moisture forecast simulation technology.In this paper, based on the principle of water balance, considering the soil water content impacted by multi-factors of soil-crop-climate, a comprehensive analysis on the changes in crop’s topsoil moisture.The thesis is divided into two parts:The first part is based on field trial data in Osnabrueck, Germany. German SJMPEL model in accordance with the principle of water balance hierarchical simulation test four layer soil moisture content changes of winter wheat in0-40cm. Potential evapotranspiration calculated by Haude calculation method.of the German DVWK standard method. Layered soil field capacity and wilting point simulated by German hydrological model SPAW (Soil-Plant-Air-Water). The SIMPEL model simulates the soil moisture from the dimension of time and space variation. SIMPEL model simulation results show that there is a significant correlation with soil volumetric water content measured data and simulation data. The model can accurately predict the root layer soil moisture content of the region, to provide guidance and services for local agricultural production, also for field water management.The second part of the test is based on the principles and theories of the preliminary studies. Meteorological data and field soil data collected in Huaibei area of Anhui Province combined with Anhui Huaibei Agricultural production habits.0-30cm single layer soil moisture model in accordance with the principle of water balance simulation model analog soil moisture content of Huaibei region between2008and2012. Practicality and feasibility are the starting point of the single layer soil model method, The model simulated by time process in accordance with the actual situation. The accuracy of the simulation results corresponds to the requirements of agricultural production. Soil moisture model of Huaibei area analyses the seasonal variation of the soil moisture, which also proposes a prediction methods in response to avoid the droughts and floods impermanent phenomenon in area Huaibei, Anhui Province. To try and explore directions for future research and improvement, and also provide a basis for future model development, supporting for future agricultural water-saving irrigation system.Comprehensive two-part study, the simulation model based on the principle of water balance, establishing the soil moisture prediction simulation model for local water research. The results show that the principle is clear, the course of the study of the model and model physical concepts are clear, the model can be continuously to simulate and predict regional moisture changing.The simulation accuracy reaches the requirements of agricultural production, also provides the necessary support for irrigation management system and drought and flood forecasting. |
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