In order to explore the effects of different fertilizer applicators on the growth and rhizosphere nutrient distribution of eggplant in solar greenhouse, this experiment took the Ermin eggplant as the research object, and set 3 types of fertilizer applicators, including Mixrite 2.5 automatic proportional fertilizer applicator (APF), adjustable proportional Venturi fertilizer applicator (APVI) and vortex fertilizer applicator (VF), to analyze the effects of different fertilizer applicators on the rhizosphere soil EC, pH, stem diameter, plant height, yield and water and fertilizer productivity of eggplant. The results showed that: by comparing the EC and pH of fertilizer solution of the three fertilizer applicators, it was found that the soluble fertilizer uniformity is APF > APVI > VF. The soil EC in eggplants rhizosphere(0~60 cm) varied from 0.1 to 0.8 mS/cm. At the end of the growth period, compared with the preplanting stage, the soil pH at 0~30 cm decreased for APF and APVI, while increased by 3.75% for VF, and at 30~60 cm, the soil pH increased by 4.33%, 4.2% and 3.91%, respectively. In the slow and rapid growth period, for the APF treatment, the stem diameter increased by 0.11 and 0.17 mm/d respectively and reached 17.44 mm at the end of the growth period. The growth curve of plant height was simulated by logistic equation, and the correlation coefficient was up to 0.99, the plant height of APF could reach a maximum of 118.51 cm. The yield of APF and APVI was 27 860.4 kg/hm2 and 27 685.05 kg/hm2, respectively, which were significantly different from that of VF. The irrigation water productivity of the first two treatments was 24.43 and 24.29 kg/m3, respectively, which was 17.81% and 17.05% higher than that of VF, and the partial fertilizer productivity was 17.78% and 17.04% higher than that of VF. Meanwhile, considering the stability, cost performance and farmers' acceptance, APVI (adjustable proportion Venturi fertilizer injector) was recommended to be popularized widely.

Aiming at the shortcoming that the traditional PSO algorithm is easy to fall into local extreme value, this article proposes an improved particle swarm algorithm (ADAPPSO). This algorithm effectively reduces the occurrence of local extreme values during the operation of the PSO algorithm by using adaptive inertial weights that exhibit a nonlinear decreasing characteristic. The ADAPPSO algorithm was used to optimize a series of parameters involved in the BP neural network, and based on this, an ADAPPSO-BP model was established to predict the reference crop evapotranspiration (ET0). Taking the data in Shangqiu area as an example, the variables were screened by the mean influence value method (MIV), and three prediction models were established based on BP neural network, PSO-BP and ADAPPSO-BP. According to relevant experimental results, the determination coefficients R2 of the BP model, the PSO-BP model, and the ADAPPSO-BP model were 89.83%, 95.27%, and 96.06%, and the average absolute errors MAE of the three models were 0.355 8, 0.240 1, and 0.205 6. Among the three models, the R2 of the ADAPPSO-BP model was the largest and the MAE was the smallest, which indicated that the proposed ADAPPSO-BP model could effectively improve the prediction ability of ET0.

Water resource plays an important role in the sustainable development of oasis in arid area. In order to realize the rational allocation of irrigation water in an oasis, the specific situation of the water cycle in Cele oasis was simulated by using the dissipative model for plain oasis in arid area, and the scale variation law of the irrigation water use efficiency in the east and west of the area was studied by taking the proportion of the evapotranspiration to the net input as the index of the irrigation water use efficiency. The results show that: in the water balance component of the study area, the land soil water input mainly depends on the channel irrigation water (about 96.02%), and the pumping irrigation amount only accounts for 0.34% of the soil water input. Due to the low reuse ratio of the returned water, the law of water use efficiency improvement with the scale is not obvious. When the number of local blocks changes from one to four, the water use efficiency in the west and east of the study area increases by 1.94% and 1.11%, respectively. The spatial difference of crops can reduce the scale effect of water use efficiency because that the irrigation water demand of food crops is larger than that of fruit trees and the water use efficiency is low. In this paper, the water equilibrium results obtained by quantitative analysis verify the feasibility of the water equilibrium model in oasis research, and provide a theoretical basis for the efficient irrigation water use in Cele oasis.

It is an important research content to use the ration proportion between crop transpiration and soil evaporation to determine the optimal fertilizer application rate to guide rational irrigation and improve water and fertilizer use efficiency. In this study, transpiration, soil transpiration, crop growth parameters and yield of summer maize were measured, and the evapotranspiration of summer maize during the whole growth period was estimated by the modified dual crop coefficient method. The effects of different fertilizing amount on plant transpiration (Tc) and soil evaporation (E) and yield of summer maize under sufficient rainfall conditions were analyzed. The results showed that the effect of fertilizer application on Tc was not significant, and the contribution of E to evapotranspiration (ETc) was greater than that of Tc. At the middle stage of growth, the greater the fertilizer application, the larger the Tc, the order was 0 fertilizer (N1) N2 > N4 > N1, the yield of N3 treatment was 16.9% higher than that of N1 treatment, the yield of N3 treatment was 9.6% higher than that of N4 treatment. Too much or too little fertilizer can reduce summer maize yields. Proper fertilization could increase the proportion of Tc in ETc (N3 highest, Tc/ETc=67.53%) and reduce the consumption of E, so that water consumption was distributed in the direction of increasing crop yield.

In order to explore the characteristics of maize yield formation, economic benefit and the response of irrigation potential to irrigation to provided theoretical basis for irrigation yield increase in the semi-arid area of western Jilin province, the change of maize yield, agronomic character and economic benefit under four irrigation quotas was studied. The Hybrid-maize model was used to simulate the potential yield increase of maize in this area. The results showed that the yield of the treatment of 120 mm (Q1), 170 mm (Q2) and 250 mm (Q3) were significantly higher than that of the treatment of 50 mm (Q0). The LAI and plant height of Q2 and Q3 treatment were significantly higher than that of Q0 treatment. The difference between the climatic production potential value of maize and the measured yield of Q2 and Q3 treatment was small, while the climatic production potential value of maize and the measured yield of Q0 treatment was large, and the measured yield of all treatments was significantly different from the production potential value of light temperature. So 170 mm can be used as irrigation reference value for corn production in semi-arid area in the west of Jilin province and the Hybrid - Maize model can be used to predict the variation trend of maize yield in semi-arid area of western Jilin province.

In order to explore the suitable buried depth and irrigation quota for underground infiltration irrigation of field eggplant, in the field experiment, three different buried depths (0, 10 and 20 cm) and three different irrigation levels (1 750, 2 250 and 2 750 m3/hm2) were arranged to study the effects of different buried depths and irrigation quotas on the growth and development, yield and water use efficiency of field eggplant. The results showed that the eggplant yield and dry matter accumulation were highest under the treatment of 10 cm buried pipe and irrigation quota of 2 750 m3/hm2; the eggplant water use efficiency was highest under the treatment of 10 cm buried pipe and irrigation quota of 2 250 m3/hm2, followed by production. In summary, under the climatic conditions of the Yellow River Irrigation Area in Ningxia, the optimal buried depth of subsurface infiltration irrigation is 10 cm, and the corresponding irrigation quota is 2 250 m3/hm2.

In order to estimate evapotranspiration in the loess plateau more accurately, this paper proposed the Remote Sensing Leaf Area Index penman-monteith model (RLPM) based on the Penman-Monteith mathematical model proposed by FAO56 and combining with the theoretical idea of LAI inversion ET proposed by Leuning. Using the synthetic product NDVI of MODIS in China and the meteorological data of the research area, the required parameter values were obtained. Taking the loess plateau as the research area, the daily ET value at any time and any place in the research area could be calculated finally. By linear analysis of the ET inversion values of this model and the inversion values obtained by the ordinary P-M model, the correlation coefficients were all greater than 0.8. The aim of this study was to enrich the calculation method of evapotranspiration model and improve the accuracy of evapotranspiration calculation.

The plant slope protection effect is closely related to the spatial distribution of roots in soil. It is of great significance to study the effect of different initial soil moisture content and dropper flow rate on the water transport in red clay, so as to reasonably match the distribution of soil moisture and plant roots, accurately regulate the plant root configuration, and improve the soil fixation capacity of plant slope. Through an indoor experiment, under the condition of indirect subsurface drip irrigation, the effects of soil initial moisture content and dropper flow rate on the characteristic value of soil wetting body, the velocity of wetting front migration and the distribution of moisture content were observed. It was found that the shape of the wetting front was approximately ellipse, while the shape of the wetting body was approximately ellipsoid; With the increase of the initial soil moisture content, the symmetry axis of the wetted body moved down continuously in the horizontal direction, and the water tended to move vertically downward, which changed with time in a logarithmic function; under the same drip irrigation amount, the range of the wetted body with small flow was slightly larger than that of the wetted body with large flow, but the radius of the wetting front changed as a power function with time. At the early stage of drip irrigation, the migration velocity of the wetting front increased with the increase of the dropper flow rate at the same time, but this phenomenon gradually weakened with the extension of the drip irrigation time; when the dropper flow was large, the trend of water movement was obvious in the horizontal direction, while when the dropper flow was small, the trend of water movement in the vertical direction was better. Different dropper flow rate and initial soil moisture content would form different shapes and sizes of wetting bodies, which would also lead to different water content distribution of wetting bodies. During the regulation of the required plant root configuration, the distribution of plant root could be controlled by controlling the dropper flow and the initial water content of soil, so as to improve the ability of plant root to hold soil.

In order to study the effect of the number of water outlets on the water flow and the yield of wheat, a field experiment of winter wheat was carried out. The water-consumption characteristics of wheat were studied by means of water-flow propulsion, cross-section water content and yield in each period of growth, respectively, by setting up the irrigation water amount of 60 mm and 75 mm, respectively represented by W1 and W2, and three kinds of water outlet quantity of 1 hole, 2 hole and 3 hole were set, respectively represented by D1, D2 and D3. The results showed that: the time of water flow propulsion increased with the increase of the number of water outlets, and the time of water flow propulsion under each treatment in the jointing period was obviously shorter than that in the return period. The variation coefficient of average soil water content was the lowest and the distribution of soil water of W2D2 treatment was more even in the furrow. W2D2 treatment had a large amount of water storage in the early stage of growth, and the water storage consumption in the later stage was greater than that of other treatments. Under the same irrigation amount, the water consumption, water consumption intensity and water consumption mode coefficient of D1 and D3 in the period from return to jointing and the period from jointing to flowering were higher than those of D2 treatment, while the water consumption, water consumption intensity and water consumption mode coefficient of D2 in the period from flowering to filling were significantly higher than those of other treatments. The water consumption increased with the increase of irrigation water amount. The yield indexes of W2D2 treatment were higher than those of other treatments and its water use efficiency was the highest. Considering the irrigation uniformity, yield and water use efficiency, W2D2 was the optimal treatment under the test conditions.

In order to find out the effects of water and nitrogen regulation under film drip irrigation on potato plant height, chlorophyll and yield in arid areas of central Ningxia, a two-factor three-level randomized block test was conducted to study the effects of different irrigation and nitrogen treatments on potato plant height, chlorophyll content and yield. The results showed that under the same irrigation conditions, potato plant height did not increase with the increase of nitrogen application rate, whilw the relative chlorophyll content increased with the increase of nitrogen application rate; there was no significant difference in plant height between different nitrogen application rates (P>0.05); under the same nitrogen application rate, potato plant height increased with the increase of irrigation amount, while relative chlorophyll content decreased with the increase of irrigation amount, plant height difference between different irrigation treatments was significant (P<0.05) The effect of irrigation amount on potato plant height was greater than that of nitrogen application. The potato plant height was highest in T7 treatment and the relative content of chlorophyll in leaves was highest in T3 treatment. Both irrigation and application of nitrogen fertilizer could increase potato yield and commercial potato yield. Under test conditions, T6 treatment potato yield was the largest and the commercial potato rate was the highest. In the arid area of central Ningxia, T6 treatment was the appropriate treatment for nitrogen and irrigation.

In order to investigate the effect of soil liquid water content and soil texture on the change of soil electrical conductivity during soil freezing process, the TDR was used to monitor the soil liquid water content and soil electrical conductivity of three soil of textures (sandy soil, sandy loam, clay) under three initial soil water content conditions (10%, 15%, 20%). The results showed that in the process of constant temperature freezing, the soil liquid water content decreased with the increase of freezing time; besides, the soil electrical conductivity decreased with the decrease of soil liquid water content, the higher the initial soil water content, the greater the decrease of soil electrical conductivity, S20, R20 and N20 decreased by 2.11, 2.50 and 2.47 dS/m respectively; What's more, the more clay particles content, the higher the soil electrical conductivity. The relationship between soil electrical conductivity and soil liquid water content in the freezing process was well fitted by the logarithmic equation, the fitting effect of sandy loam was better, and R2 were all greater than 0.945. The research results can provide references for agricultural production and the control of soil salinization in seasonal frozen soil areas of China.

In view of the current situation of drought, less rain and lack of water resources in the western desert area of Gansu province, the applicability of modified desert sand in afforestation in arid desert areas was studied by analyzing the effects of sand-laying treatment and irrigation control on seedling growth and soil moisture content of populus euphratica and populus talassica× p.euphratic as typical desert plants. The results showed that the application of modified desert sand could prevent evaporation, conserve water and effectively promote the growth and development of populus euphratica seedlings. In the second year of seedling planting, top sand treatment and irrigation control could significantly improve the soil moisture content in the 0~40 cm soil layer. Compared with the control group, the chest diameter and ground diameter in the test group were 66.53% and 46.74% higher than those in the control group. The results of the study have a strong practical guiding significance for the water-saving irrigation of afforestation in arid desert areas in Hexi of Gansu province.

In order to find out the effects of acidified water quality and different functional fertilizers on the growth and development of fruit corn and soil quality, six treatments were set up under the irrigation of pH 7.5 ordinary water and pH 6.0 acid water respectively, including total nutrient fertilizer, total nutrient fertilizer with functional preparation, total nutrient fertilizer with functional conditioner, to study the growth and development, quality of fruit corn and soil nutrition. The results showed that the application of functional agents and regulators could significantly improve the SPAD value and net photosynthetic rate of fruit corn leaves, effectively reduce the height of ear position, promote the dry matter accumulation, and the maximum yield reached 20 685 kg/hm2, which had significant accumulation effect on the content of soluble solids, VC and soluble sugar in corn grains, and at the same time, the content of soil organic matter and available nutrients Quantity were improved. After acidification of water quality, the treatment of total nutrient water-soluble fertilizer with functional preparation could significantly improve the chlorophyll content of corn leaves in the silking stage and milk maturity stage. Under the condition of pH 6.0 irrigation water, the combination of functional agent and functional conditioner was beneficial to the growth of maize and could keep the soil nutrients.

In this paper, the effects of drought stress on grape skin coloration during initial veraison were studied by using facility cultivation of summer black grape as the material and normal irrigation as the control. The results showed that drought stress during initial veraison could lead to the increase of MDA content and the increase of antioxidant enzyme activity in grape skins, which was beneficial to the accumulation of reducing sugar and titrable acid, especially in the 50% coloration stage. In addition, drought stress in this period promoted the accumulation of total phenols, flavonoids and anthocyanins in grape skins. It is believed that drought stress during initial veraison can regulate the growth and development of fruit and promote fruit coloration.

In order to explore the optimum fertilizer application and planting density for higher grain yield, quality and water use efficiency, and to provide basis for the development to fractional cultivation measures, the wide uniform planting method were used in this study. Under field condition, three fertilization rates (N:120、150、180 kg/hm2, P2O5:90、105、120 kg/hm2 and K:60 kg/hm2) and four regimes of planting density (190, 230, 270 and 310 kg/hm2) were applied to study the interaction between fertilizer and density on grain yield, quality and water use efficiency of dryland wheat. The results showed that planting density, fertilization rate and the interaction between them had significant effects on grain yield and yield components of dryland winter wheat under wide uniform planting; the number of productive ear was sensitive to fertilization, whereas the kernel number and weight were mainly affected by plant density; in the range of fertilizer application F120~F150 and planting density D190~D270, the yield increased with the increase of fertilizer application and planting density; when the amount of fertilizer applied exceeded F150 and the planting density was greater than D270, the yield decreased; The results also showed that the combination of F120~F150 and D270~D310 could improve the quality and yield; in the range of F120~F180, the water use efficiency increased by 48.5% and 24.8% with the gradual increase of fertilization level, but the water use efficiency increasing rate decreased. Considering yield, quality, water use efficiency and other factors comprehensively, under the conditions of this experiment, the suitable fertilizer application amounts for achieving high yield, high quality and water saving of dryland winter wheat under wide uniform planting were N 150 kg/hm2, P2O5 105 kg/hm2, K2O 60 kg/hm2, and the planting density was 270 kg/hm2.

The climate in Tarim Basin is dry, and its agriculture mainly relies on irrigation, which will definitely have an important impact on the local climate. In order to better understand how farmland irrigation can change the local climate in arid regions of Xinjiang and quantify the role of irrigated farmland in the local climate system, we chose the Tarim Basin in northwest China as a typical study area. This study firstly added a reasonable irrigation scheme to the CLM (Community Land Model) land surface model in the regional climate model WRF (Weather Research and Forecasting), and then designed two sets of experiments (with and without irrigation), and simulates them continuously for 10 years (2006-2015) in the crop growing seasons(May-September). The effects of irrigation on local climate in Tarim Basin were studied by comparisons with observations through model simulations. The results indicated that the modified model can simulate land surface temperature, near-surface air temperature, and precipitation similar to the observations. Not only the warm biases of the original model over irrigated areas are significantly reduced, but also the cooling and wetting effects induced by irrigation lead to a reduction of precipitation bias. In addition, the irrigation caused a slight increase in precipitation over irrigated areas, but precipitation around irrigated areas increased significantly. Therefore, the increase of precipitation induced by irrigation can alleviate the pressure of irrigation demand in arid regions, and it will also have an important impact on the local arid climate.

Aiming at the defect of traditional analytic hierarchy process (AHP) which was easily affected by subjective factors, OWA operator was adopted to reduce the influence of subjective extreme value deviation on the accuracy of weight and correct some defects of traditional AHP. Finally, the OWA-AHP-TOPSIS coupling model was constructed by using TOPSIS to quantify the relative relationship between samples and standards. The model was applied to Dagu River Basin, with 7 indexes of total hardness, Cl-,TDS, SO2-4, NO-3, NO-2 and NH+4 were selected as evaluation factors to evaluate groundwater quality of 12 water sample points in the basin. The results showed that 41.7% of the selected water samples were classified as class Ⅲ water and 58.3% as class Ⅳ water. The water quality pollution was generally serious, especially in the north and south of the region, which was related to unreasonable domestic sewage discharge of local residents, low efficiency of agricultural fertilizer utilization and so on. Therefore, corresponding remediation should be carried out. Meanwhile, it was found that the coupling model could obtain more objective evaluation results in the areas with serious pollution with better applicability through comparing OWA-AHP-TOPSIS coupling model with AHP-TOPSIS method, single factor index method and Nemero index method in water quality evaluation results.

In order to understand the health risk of heavy metals in groundwater in Kashgar region，this investigation focused on the contents and health risk assessment of heavy metals of shallow groundwater in Kashgar region. 68 groundwater samples were collected. The concentrations of 10 heavy metals were studied based on the Standard for Groundwater Quality (GB/T 14848-2017).The pollution levels of heavy metals in groundwater were analyzed based on the Nemerow Pollution Index. A fuzzy model based on triangular fuzzy number theory was developed to evaluate the human health risk of heavy metals in groundwater. The results showed that the excess rates of heavy metals in the shallow groundwater in the study area were Mn, Ni, Fe, As, Cd and Hg in descending order, among which Mn, Ni, Fe and As were the main supernormal elements. The mean order of heavy metal pollution index in groundwater in the study area was Mn (5.21), Ni (3.04), Fe (1.92), As (0.68), Cd (0.62), Hg (0.25) and Zn (0.04). The comprehensive pollution index ranged from 0.44 to 20.82, with an average value of 4.61, indicating heavy pollution. The total non-carcinogenic risk was within the acceptable range, the total carcinogenic risk exceeded the safety threshold and Cd and As were the primary environmental health risk management indicators. This study indicated that heavy metals in the local drinking water route could cause carcinogenic risk.

In view of the problem that the decision-making information of water-saving irrigation project cannot be obtained accurately, the three parameter interval number was used to evaluate the water-saving irrigation project. The improved entropy method was used to calculate the weight of attributes, the TOPSIS method and grey correlation algorithm was used to calculate the relative closeness degree of different schemes, the value of relative closeness was used to sort the schemes, and the algorithm was applied to the optimization of water-saving irrigation projects. The results verified the effectiveness and rationality of the algorithm.