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Waste water from the animal production industry contains large amounts of nitrogen, phosphorus and organic matter, which can easily cause water pollution. Continuous-cropping of Artemisia selengens causes the accumulation of the serious soil-borne pathogen Fusarium oxysporum , resulting in serious disease in cutting seedlings. For the containment of organic matter and the flowability of waste water, the experiment to assay the biocontrol capacity of the waste water fortified with the biocontrol agent Bacillus subtilis D9 against F. oxysporum was performed. The results showed that the population of soil D9 significantly ( P 0.05) affected the Fusarium wilt disease incidence of A. selengens and a higher population of D9 in the soil was correlated with a lower disease incidence of A. selengens . The effects of factors such as the irrigation quantity of treated waste water (TWW), the irrigation quantity of tap water, the percentage of D9 spores, the soil bulk density and the additive ratio of adsorbent in the soil population of Bacillus spp. were determined.The irrigation quantity of TWW, the irrigation quantity of tap water and the additive ratio of poly-γ-glutamic acid were selected as significant factors and were optimized using Central Composite Design. The optimal factors were a TWW irrigation quantity of 2.35 ml cm −2 , a tap water irrigation quantity of 3.21 ml cm −2 , and a poly-γ-glutamic acid additive ratio of 1.11 g L −1 . Validation of the predictive gained population of soil Bacillus was 1.92 × 10 8 cfu g −1 , which was close to the predicted value of 2.0 × 10 8 cfu g −1 . Compared with the control (soil not irrigated with waste water) and WW (soil irrigated with waste water) treatments, the disease incidence with the TWW (soil irrigated with treated waste water) treatment was significantly decreased. The biocontrol efficacy of TWW treatment was 92.5%. TWW significantly decreased the population of F. oxysporum by 47.1% in the rhizosphere soil and by 87.7% in the stem of A. selengens ( P 0.05). These findings support a new value-added application method for waste water from the animal production industry.

Through real-time monitoring of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), total nitrogen (TN) and total phosphorus (TP) in the aquaculture wastewater, the purification effects of EM techniques by applying EM active calcium, Microbial nanoSilica Ball and both of them were studied. The results showed that the purification effect of solid preparation for Microbial nanoSilica Ball was better than that of the liquid preparation for EM active calcium. Moreover, the purification effect with the technological cooperation of Microbial nanoSilica Ball with EM active calcium reached best, indicating that the removal rate of COD, NH4+-N, TN and TP in the aquaculture wastewater was 72.12% , 73.85% , 64.99% and 67.87% respectively.

In order to explore the effects of water-nitrogen coupling on dry matter and nutrient accumulation of flue-cured tobacco, 9 treatments with different lowest limits and nitrogen fertilizer amount were designed, and the distribution and accumulation of dry matter and nutrient (N, P and K) of flue-cured tobaccos under water-nitrogen coupling treatments were observed. Results showed that: (1) High irrigation amount could not certainly increase the dry matter accumulation of tobacco root, but which was beneficial to the dry matter accumulation of whole tobacco plant. (2) Dry weight proportion of flue-cured tobacco leaves was highest, which was above 55% among the treatments. (3) Higher water and nitrogen promoted the nutrient accumulation of flue-cured tobaccos, nutrient content of W3N3, W3N2 and W2N2 was higher compared to other treatments.

Field study was conducted to determine the optimum irrigation quantity and times of corn in 2010. Different irrigation treatments were set according to local farmers’ practices. Irrigation amounts of T1, T2, T3, T4, T5 and T6 were 225, 270, 337.5, 300, 360 and 450 mm, respectively. Irrigation times of T1, T2 and T3 were 3, and T4, T5 and T6 were 4. The results showed that soil salt decreased with the increasing of irrigation water amounts. The corn yield varied from 6560 to 8060 kg/ha2. The highest yield was obtained from T5. Aiming to get high corn yield, total water supply of corn crops was 865 mm. Irrigation water productivity (Wpi) was the highest (2.92 kg/m3) with T1, and the lowest (1.74 kg/m3) with T6.

A pot experiment was conducted on soil evaporation of flue-cured tobaccounder water and nitrogen fertilizers coupling treatmentsin this study. Soil evaporation at each growth stage of tobacco were analyzed, so did ratio of average soil evaporation (AEa) to mean water consumption (AET). Some factors impacting soil evaporation were also investigated. The results showed that average daily soil evaporation was positively correlated with soil temperature (p), the equation between daily soil evaporation and surface soil moisture (θ) was AEa=0.058e0.048θ (R2=0.717), while relationship between the ratio of evaporation to water consumption (AEa/AET) and leaf area index (LAI ) was functioned as AEa/AET=0.201 LAI-0.912(R2=0.658). It also suggested that the best effects to decrease soil evaporation of flue-cured tobacco appeared in treatment of 6g N per plant combined with the irrigation amount and frequency at 4.5kg and 9 times, 18kg and 18 times, 13kg and 26 times at root spreading stage, vigorous growing stage and the maturing stage respectively.

The experiments were carried out in lysimeters to study water consumption characteristics and water use efficiency of flue-cured tobacco under different conditions of irrigation. By comparing the T and the invalid E of the tobacco K326, it is concluded that in the period of root extending most of the irrigation water is used for the E, in the early vigorous period, plants with all of the treatments show a T higher than the E, in the late vigorous period and the maturity, this ratio remains at 50%. Based on measured data, it was shown that the amount of irrigation water in the vigorous period had the most important influence on the yield of the tobacco.The nonlinear equation of the yield and WUE is Y=-2531.3X2+6113.8X-624.49,R2=0.7324; the equation of the yield and ET is Y=4E-0.7X3-0.0032X2+8.8458X-4806.7, suggesting that the WUE is not maximized at the highest yield of flue-cured tobacco. In the high-yield range, reducing irrigation appropriately could reach the harmonization of high production and water saving.

EM enrichment culture liquid was immobilized on nano-silica carrier to form microbial nano ball, so as to investigate the reaction kinetics of ammonia nitrogen (NH4+-N) by microbial nano ball. The results showed that first order reaction kinetics model could describe NH4+-N removal by different diameter microbial nano-silica balls well. And the microbe could keep higher biological activity between 0-72h. Reaction kinetic equations of NH4+-N were: (1) when diameter was 10mm, (0-48h), (48-72h); (2) when diameter was 20mm, (0-48h), (48-72h); (3) (0-48h), (48-72h).

EM enrichment culture liquid was immobilized on nano-silica carrier consisting of pond sediment, zeolite powder and nano-silica to form microbial nano-silica ball. Influencing factors of initial ammonia nitrogen (NH4+-N), COD, pH and dissolved oxygen (DO) concentrations on wastewater purification by microbial nano-silica ball were studied. The results showed that removal rate of NH4+-N, total nitrogen (TN) and total phosphorus (TP) was the highest with COD concentration of 500mg/L when initial COD was ranged from 250 to 2000mg/L. On the condition of initial NH4+-N concentration ranged from 50 to 500mg/L, removal amount of NH4+-N and TN in wastewater reached the maximum when NH4+-N concentration was 400mg/L. On the condition that pH was ranged from6 to 9, removal effect of pollutants was the best when pH was 8. The results also showed that NH4+-N and TN removal rates in wastewater could be increased by appropriate aeration. But aeration had no effect on TP removal rate in wastewater.

Aquatic environment influences the quantity and quality of aquatic livings directly. In China, aquatic environment has been contaminated seriously as the rapid development of aquaculture industry. Bioremediation, mainly including efficient microbial agent method, immobilized microbe method, aquatic plant method, aquatic animal method and constructed wetlands method, can absorb and assimilate the organic and inorganic pollutants even toxic heavy metals in effluent, degrade them to innocuous substances through metabolism of microorganisms, aquatic plants or aquatic animals. Researches and demonstration showed that bioremediation could effectively decrease NH+4-N, NO−X-N, COD, SS generated by excess bait, fish manure, biological excrements and sediments, increase aquatic transparency, DO and stable pH value in aquaculture water. In future, theoretical researches should be enhanced on improvements of individual as well as integrated bioremediations which will contribute to sustainable development of aquaculture.

To form microbial nanoball, EM active calcium was immobilized on nano-silica carrier consisting of pond sediment, zeolite powder and nanosilica. Through real-time monitoring of pH, dissolved oxygen (DO), chemical oxygen demand (COD) and ammonia nitrogen (NH4+-N) aquaculture wastewater, the purification effects of Microbial nanoSilica Ball on aquaculture wastewater under different mud-water ratio condition were studied. The results showed that the purification effect reached best in 3-6 days for all treatments and was better for mud-water ratio of 1:2.7. In this mud-water ratio, it was indicated that pH was maintained at 7-8.5 which was an optimum value for the aquaculture, the content of DO was increased by 82.16% compared with the initial value and the removal rate of COD and NH4+-N was 57.80% and 54.60% respectively.

Field experiments were conducted for controlled and mid-gathering irrigation mode in Nanjing, Jiangsu Province, focusing on the effect analysis of this mode with different fertilizations on profile soil total nitrogen and alkali-hydrolyzale nitrogen distributions and rice yield compared with the conventional irrigation mode. Results obtained showed that both total nitrogen and alkali-hydrolyzale nitrogen in soil profile were decreased with the increase of soil depth. Fast decrement of total nitrogen was found from surface 0-20 cm of soil layer and it reached the plateau below 40 cm of soil layer. Under the same fertilizer application, both total nitrogen and alkali-hydrolyzale nitrogen in surface soil layer were lower under controlled and mid-gathering irrigation mode which reduced the loss risks of runoff and leaching of soil and fertilizer nitrogen. Controlled and mid-gathering irrigation reduced water comsumption and N pollutant discharge without significant changes in rice yield compared with conventional irrigation. Conjunction of organic and inorganic fertilizers significantly improved the rice yield and utilization rate of nitrogen.

In allusion to environmental pollution brought about by wastewater irrigation, EM technology was introduced to study the feasibility of EM application in wastewater irrigation. The results show that EC, NO3--N and TN value of EM treatment in shallow groundwater are all less than those of WW treatment as a whole. In all samples, 59.3% NO3--N values are in the alert status, and when irrigation amount reaches 360mm, treatment WW has caused shallow groundwater pollution. TN concentration in treatment WW-3 on June 27 and July 9 is more than 110 mg/L. It suggests that NO3--N can easily penetrate into shallow groundwater with wastewater irrigation and there is insurance of groundwater pollution in the long-term wastewater irrigation. It also indicates that application of wastewater treated by EM reused for irrigation is feasible. TP values are all very low and suggest the pollution of P does not happen.

Nitrogen utilization efficiency (NUE) was a hot topic in the study area of crop cultivation, most scholars tented to calculate NUE by D-value method, which could well reflected the total absorption of N nutrient by crops; and on the other hand, the tracing technique could precisely calculated the N content which crops absorbed from N fertilizer. In this study, the flue-cured tobaccos were treated with 2 N levels and 3 water levels, and the D-value method and the tracing method was adopted to calculate the nitrogen utilization efficiency. Results showed that the RD value was more than double the RN value, and there were no relationships between the results calculated by the D-value method and the tracing method, the treatment with higher RN value could not always obtain a higher RD value; besides, water deficiency or excess could both decreased NUE, through affecting the N availability or through the elution of the N nutrient. Taken as the whole, 6g/plant N combined with 800mm irrigation water was more beneficial for the effective utilization of N fertilization, and which combined with 1000mm was more beneficial for the N accumulation of tobacco plants.

Based on field experiment, the yield and water use efficiency (WUE) of tobacco under different nitrogen levels were studied in Hunan province, China. The results show that the evaportranspiration (ET) of flue-cured tobacco dealt with N2 (90kg N fertilizers per ha) gets to the maximum. In addition, the vigorous period has the maximum ET due to the critical period of water requirement. The linear relationship is established among fertilization, yield and water use efficiency. Reasonable fertilizer application can increase water use efficiency and flue-cured tobacco yield.

The blossom-end rot (BER) induced by calcium deficiency will cause a great impact on tomato yield and quality. Aimed at the tomato physical barriers caused by calcium deficiency, the composite micro-organisms (EM) fermentation technology was applied to configure biological active calcium preparations of different calcium concentrations, with raw materials of calcium sulfate, lime and gypsum. The active calcium preparation with calcium concentration of 1 ‰ was sprayed on the fruits during the fruit development period in the field experiment. The results show that lime with highest solubility is the best raw material for the fermentation of EM active calcium preparations with the consideration of higher calcium concentration, reasonable pH and EC value, and the lowest cost. It also shows the incidence of blossom-end rot of the experimental group is 35.36 % lower than that of CK.

Raising nitrogen utilization efficiency could not only cut the fertilizer costs, but also reduce the N loss and residual, which benefits a lot to agricultural production and environmental protection. In this experiment, the 15N tracing technique was employed in order to clear the accumulation and whereabouts of fertilizer N in flue-cured tobacco plants, besides, the tobaccos were treated by six different water-nitrogen modes, for the sake of finding out the best design with the highest nitrogen utilization efficiency. The results showed that more N application contributed to more fertilizer N accumulation, also increased the content of total N; Excess irrigation restrained the tobacco plants' absorption of fertilizer N, ultimately leading to the low utilization efficiency of nitrogen fertilizer; After apex pruning, the N offering ability of the soil was much stronger than that of nitrogen fertilizer, and the fertilizer N accounts a relatively small part for the total N in tobacco plants, the highest nitrogen utilization efficiency was 24.16%, recorded in the design of 800mm irrigation amount and 6g/plant pure N application(T2), Meanwhile, the agronomic characters and crop yield was observed, tobaccos in T2 design performed better than the average level of field-cultivated tobaccos, the conclusions could be obtained that T2 design was preferable, which achieved the highest nitrogen utilization efficiency when ensured the normal growth and good harvest of flue-cured tobacco.

The secondary salinized greenhouse soil was provided with subsurface pipe drainage system with drainage spacing 6 m and drain depth 0.4m to study the movement of salt and water. The field investigations indicated that the resalination rates of the surface soil with subsurface drainage system were lower than those with non-drained system (CK) in an irrigation circle of the crop. The resalination rate of the surface soil right above the drainage tubes (T1) was significantly lower than that between the two drainage tubes (T2). At the 5th day after irrigation, the soil volumetric moisture contents of different treatments were significantly decreased and the resalination of surface soil were obvious. The results showed a considerable increase of resalination rate after irrigation that was varied at the 5th day as following sequence: CK(10.6%) > T2(8%) > T1(7%).

This paper describes a designed new nozzle and provides experimental studies on the nozzle used in high-pressure fog cooling system in Greenhouses. Fogging droplet sizes of the nozzle is measured by MPA Malvern Particle Analyzer. The diameter of droplet sizes (VMD, Dv10, Dv50, Dv90) which is 500 mm far from the nozzle is measured and analyzed when the pump pressure is 2, 3, 4, 5, 6,7MPa.The experimental results shows: the nozzle has fine fogging performance, and its droplet sizes (VMD) are small and less than 30 microns when operating pressure is more than 5MPa.

Bedding materials are very important for cows in freestalls, because they can provide a high degree of comfort to these cows. But techniques of assessing their surface comfort on in the field still remain rather subjective. The objective of this study was to assess softness of bedding materials for use in cow free-stall bases in China. The Clegg Impact values of rubber-coated slatted floor, Solid wood floor and concrete floor are measured in order to compare with the value of pasture. The softest bedding material was the wood (40.43CIV/L) followed by rubber-coated slatted floor (64.23 CIV/L). The hardest material was the concrete floor (132.21 CIV/L).Clegg Impact Tester with a 1-kg hammer was used in this study. The impact of the hammer on bedding materials results in a digital display based on peak deceleration of the hammer’s impact with the free-stall base in tens of gravities (CIV/L). The CIV/L value, as measured by the Clegg Impact hammer, is based on peak deceleration of the 1-kg hammer’s impact with the surface, from a height of 30 cm. The reasonable suggestions of bedding materials used as the free-stall bases are recommended for the farmer in China.

In order to identify the principal factors influencing soil water characteristics (SWC) and evaluate SWC effectively, the multivariate-statistical canonical correlation analysis (CCA) method was used to study and analyze the correlation between SWC and soil physical and chemical properties. Twenty-two soil samples were taken from 11 main tobacco-growing areas in Guizhou Province in China and the soil water characteristic curves (SWCC) and basic physical and chemical properties of the soil samples were determined. The results show that: (1) The soil bulk density, soil total porosity and soil capillary porosity have significant effects on SWC of tobacco fiels. Bulk density and total porosity are positively correlated with soil water retention characteristics (SWRC), and soil capillary porosity is positively correlated with soil water supply characteristics (SWSC). (2) Soil samples from different soil layers at the same soil sampling point show similarity or consistency in SWC. Inadequate soil water supply capability and imbalance between SWRC and SWSC are problems of tobacco soil. (3) The SWC of loamy clay are generally superior to those of silty clay loam.