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To evaluate the applicability of AHC (agro-hydrological chemical and crop systems simulator) model and explore the suitable irrigation amount for peanut (Arachis hypogaea) under mulched drip irrigation in the semi-arid areas of northwestern Liaoning Province, based on the two-year field experimental data of peanut in 2016 and 2017, the model parameters were firstly chosen for global sensitivity analysis. Then, module parameters of soil moisture and crop growth were calibrated and validated. Finally, AHC model was used to analyze the responses of peanut yield and water use efficiency (WUE) to different irrigation amounts. The results showed that the two extremely sensitive parameters of the model were saturated hydraulic conductivity in the first and second layers of soil. Root mean square error (RMSE) and mean relative error (MRE) between simulated and measured values of soil water content ranged from 0.02 to 0.03 cm为评价AHC模型在辽西北半干旱地区的适用性及寻求花生膜下滴灌条件下的最优灌水量,本研究以2016、2017年花生田间试验数据为基础,首先对模型参数进行全局敏感性分析,然后对土壤水分、作物生长模块参数进行率定及验证,最后应用AHC模型分析了试验年份花生产量和水分利用效率对不同灌水量的响应。结果表明: 模型的极敏感参数为土壤第1、2层的饱和导水率。校验过程中,土壤含水率模拟值与实测值的均方根误差(RMSE)和平均相对误差(MRE)分别在0.02～0.03 cm

This paper illustrated the drought resistance strategy, analyzed the profile, characteristics, development tendency and the cause of the drought in Guizhou Province. And the paper analyzed the major measures and achievements of the drought resistance emphatically to provide a reference basis for Guizhou drought resistance.

Historical characteristics of crop evapotranspiration and irrigation requirement were the bases for determining the irrigation quota in local areas. Based on the trials of two years, crop evapotranspiration and crop coefficient of corn at monthly growth stages were determined and tested by soil water balance method in Fuxin of the southern kerqin sandy land. Using the weather data in Fuxin and Chaoyang from 1953 to 2009, estimated the coupling degree between crop water requirement of λ and apply irrigation water (ETaw) in growing season under three hydrologic years (P=25%,50%and75%).Under the humid year (25%),λ (0.756) in Fuxin was more suitable than Chaoyang (0.694),ETaw(95.5mm) in Fuxin was lower than Chaoyang (148.7mm);under the normal year (50%),λ(0.622) in Fuxin was close to Chaoyang (0.647),ETaw(180.4mm) in Fuxin was higher than Chaoyang (154mm); under droughty year (75%), λ (0.574) in Fuxin was also more suitable than Chaoyang (0.523),ETaw (204.8mm) in Fuxin was also lower than Chaoyang (245mm). The monthly change of λ and ETaw were sharping and influenced irrigation frequency in the growing season of humid and droughty year. The method and results can be further applied to agricultural water management study and guide irrigation in other same regions.

In this paper, the fuzzy controlling system of automatic irrigation was prepared and designed based on MINI2440 and C8051F410 MCU, in which MATLAB was embedded in C8051F410 MCU while WINCE5.0 was embedded in MINI2440. In the progress, the WINCE5.0 was developed by using C#. All the simulate results of fuzzy controller were shown by SIMLINK in the system. In this paper, we proposed a novel control mode and gave the Robust Control Algorithm of the fuzzy Control System.

A Local Piecewise-Linearity Prediction method is presented, Based on the advantages and limitations of local prediction of chaotic time series. Taking time series of rainfall as example for prediction the rainfall of one city in Liaoning province, which includes the application of the largest Lyapunov exponent, Local-region method and Local Piecewise-Linearity method. The method proposed is proved practical in comparison with the observed data.

This article mainly aimed at the Karst slope characteristics, designed a kind of network based on ZigBee irrigation control system. The lower position machine node in this system powered by solar energy, in accordance with the regulation of crop water requirements for irrigation, and synchronously measureed pipe flow of all levels. According to the isosceles triangle(type B)to decorate irrigation points and the diagonal 5 forms to fix the sensor mentioned in this article for crop irrigation experiment, and the pipes flow are measured.

In order to overcome the difficulties existing in estimating the multiple threshold values in multiple threshold regression models, a new Multi-threshold regression prediction method is proposed using Particle Swarm Optimization (PSO) in this paper, realizing estimating the multiple threshold value of multi-threshold regression (MTR) model. This method expands the prediction factors at the beginning, reduces the dimension using principal components analysis, searches threshold value by PSO and then establishes threshold regression model. A set of common modeling solutions of MTR is presented based on PSO at the same time. And this modeling solution is applied to the prediction of Reference Evapotranspiration (ET0) in the Panjin area. Results indicate this model has high precision for prediction and its application will provide a new means for predicting annual cumulative ET0.

Pot experiments were conducted under different status of soil moisture potential during different stages of rice. The results show that soil moisture potential regulation and control is able to increase the rice yield at each growth stages after returning green, the suitable soil water potential criteria for middle-season rice in Liaoning province at different stages is 5~10kPa in tillering initial stage, 35kPa at most in tillering final stage, 5~10kPa in jointing and heading stages, not more than 20kPa in Milk maturity stage; re-watering post drought has a compensation effect to rice whose soil suction potential is controlled in 5~10kPa at tillering initial stage according to the results that its tillers number, output, final root dry biomass and leaf dry weight were significant exceeding contrast; The research on rice quality indicates that water stress in jointing stage increase protein content but reduce eating quality.

The aims of this research were to compare subsurface drip irrigation scheduling and nitrogen fertilization rates in cucumber, and evaluate yield and quality of cucumber fruit, water (WUE), irrigation water (IWUE), and nitrogen use (NUE) efficiencies in the solar greenhouse in Southwest China. The irrigation water amounts were determined based on the 20 cm diameter pan (Ep) placed over the crop canopy, and cucumber plant was subjected to three irrigation water levels (I1, 0.6 Ep; I2, 0.8 Ep; and I3, 1.0 Ep) in interaction with three nitrogen fertilization levels (N1, 300 kg ha−1; N2, 450 kg ha−1; and N3, 600 kg ha−1). The results showed that the cucumber fruit yield increased with the improvement of irrigation water. Irrigation water increased yields by increasing the mean weight of the fruits, and also by increasing fruit number. But the highest values of IWUE and WUE were obtained from I2 treatment. NUE significantly decreased with the improvement of N application, but increased by irrigating more water. The quality of cucumber fruit decreased with the improvement irrigation water and nitrogen fertilization. In conclusion, the optimum irrigation level and nitrogen fertilizer application level for cucunber under subsurface drip irrigation in the solar greenhouse in Southwest China were 0.8 Ep and 450 and 600 kg ha−1, respectively.