Soilless (hydroponic) vegetables and fruits grown in greenhouses are gaining popularity and potentially represent a compliment toward sustainable food sources. Only a few studies have looked at the nutrient quality of...Soilless (hydroponic) vegetables and fruits grown in greenhouses are gaining popularity and potentially represent a compliment toward sustainable food sources. Only a few studies have looked at the nutrient quality of strawberries (Fragaria × ananassa) and raspberries (Rubus idaeus) grown in soilless systems. Dry weights, content of ascorbic acid, tocopherol, total polyphenolic compounds, glucose, fructose, and soluble solids (BRIX) of strawberries and raspberries grown in soilless systems were compared to their counterpart grown in soil. There was no change in dry weights but BRIX values (28% - 31%), glucose (158% - 175%), and fructose (75% - 102%) content for strawberries and raspberries respectively were significantly higher for the soil grown berries compared to soilless grown berries. Contents of ascorbic acid, tocopherol and total polyphenolic compounds were significantly higher in soilless grown strawberries compared to soil grown strawberries by 74%, 53%, and 22% respectively, and contents of ascorbic acid and total polyphenolic compounds were significantly higher in soil grown raspberries by 83% and 67% respectively compared to soilless grown raspberries. Soilless grown produce warrants future research to strive toward the potential to provide nutrient dense crops and opportunities toward optimized sustainable production.展开更多
[Objective]The paper was to screen out planting mode suitable for mini-watermelon in spring greenhouses under soilless cultivation.[Method]The effects of single row planting with one main vine and one lateral vein,dou...[Objective]The paper was to screen out planting mode suitable for mini-watermelon in spring greenhouses under soilless cultivation.[Method]The effects of single row planting with one main vine and one lateral vein,double row planting with one main vine and one lateral vein,and double row planting with two lateral veins on the growth period,growth,fruit quality and yield of mini-watermelon were studied.[Result]The planting mode of single row planting with one main vine and one lateral vein was adopted.The earliest date of harvest was May 28;the fruit-setting rate was 106.3%;and the single fruit weight was 1.33 kg.The lowest abnormal fruit rate was 0.73%;the highest yield was 54465.45 kg/hm^2,and the central sugar content was the highest of 12.95%.[Conclusion]Single row planting mode under soilless cultivation has certain demonstration and popularization prospect.展开更多
In order to screen out the small watermelon varieties with red flesh suitable for soilless cultivation and to meet people's requirements of high-quality watermelons,comparative tests were conducted on 6 small wate...In order to screen out the small watermelon varieties with red flesh suitable for soilless cultivation and to meet people's requirements of high-quality watermelons,comparative tests were conducted on 6 small watermelon varieties with red flesh under soilless culture conditions in 2018.Based on the data of field traits,yield traits,quality traits and commercial traits,the integrated results showed that ‘Chuanqi 2’ had good quality and high yield,and the overall performance was the best.展开更多
[Objective]The paper was to study the effects of different plant densities on growth,yield and quality of mini-watermelon under soilless cultivation.[Method]Five planting densities were designed under double row plant...[Objective]The paper was to study the effects of different plant densities on growth,yield and quality of mini-watermelon under soilless cultivation.[Method]Five planting densities were designed under double row planting with one main vine and one lateral vein in soilless cultivation,including 5.25×10^4,3.90×10^4,3.15×10^4,2.70×10^4 and 2.25×10^4 plants/hm^2.[Conclusion]Under the planting density of 3.15×10^4 plants/hm^2,the yield of mini-watermelon was the highest of 58.719 t/hm^2;the yield of plot was the highest of 260.97 kg;the central sugar content was the highest of 13.20%;the earliest date of harvest was June 1,ranking second;the fruit setting rate was 108.9%;the single fruit weight was 1.72 kg;and the malformed fruit rate was 0.48%.[Conclusion]Under soilless cultivation,3.15×10^4 plants/hm^2 is the best planting density.展开更多
Vertical cultivation is the most important method in the future spatially in smart agriculture systems. The fourth different thickness soilless textile was used as the board to cultivate water-cress (Eruca Sativa). Th...Vertical cultivation is the most important method in the future spatially in smart agriculture systems. The fourth different thickness soilless textile was used as the board to cultivate water-cress (Eruca Sativa). The vacuum pump model VRI V3 Dual Stage Vacuum Pump was constructed and used in the preliminary experimental test. It’s run to measure the water content and water absorption percentage for soilless board under lab conditions. Different tests were evaluated for the absorption sample after elapsed time 0.08, 0.17, 0.25, 5, 24 and 120 hours. Soilless board textile with thickness 32 mm, 26 mm, 21 mm and 16 mm made from the following material: woven fabric of Cotton. The four mattresses of smart textile as soilless vertical cultivation, measuring 40 cm width 60 cm length were created;it has filler from soft sawdust, a mixture of red (beech) and white (Swedish) wood. The result of preliminary test illustrated that the soilless board may be able to keep the amount of water for more than 72.3% after 5 days from edit water to soilless board. The soilless smart with 32 mm thickness gave highly growths of water-cress compared with the other smart mattress.展开更多
Soilless culture in China has developed rapidly in recent years. The area of soilless culture in China was about 0.1 ha in 1985, 117 ha in 1995, but in 2002 the area reached to 865 ha. This paper introduced the brief ...Soilless culture in China has developed rapidly in recent years. The area of soilless culture in China was about 0.1 ha in 1985, 117 ha in 1995, but in 2002 the area reached to 865 ha. This paper introduced the brief history of soilless culture in China, and the main soilless culture systems. The present situation and problems are also discussed in this paper.展开更多
Plasma nitrogen fixation(PNF)has been emerging as a promising technology for greenhouse gasfree and renewable energy-based agriculture.Yet,most PNF studies seldom address practical application-specific issues.In this ...Plasma nitrogen fixation(PNF)has been emerging as a promising technology for greenhouse gasfree and renewable energy-based agriculture.Yet,most PNF studies seldom address practical application-specific issues.In this work,we present the development of a compact and automatic PNF system for on-site agricultural applications.The system utilized a gliding-arc discharge as the plasma source and employed a dual-loop design to generate NO_(x)from air and water under atmospheric conditions.Experimental results showed that the system with a dualloop design performs well in terms of energy costs and production rates.Optimal operational parameters for the system were determined through experimentation,resulting in an energy cost of 13.9 MJ mol^(-1)and an energy efficiency of 16 g kWh^(-1)for NO_(3)^(-)production,respectively.Moreover,the concentration of exhausted NO_(x)was below the emission standards.Soilless lettuce cultivation experiments demonstrated that NO_(x)^(-)produced by the PNF system could serve as liquid nitrate nitrogen fertilizer.Overall,our work demonstrates the potential of the developed PNF system for on-site application in the production of green-leaf vegetables.展开更多
近年来,随着石油勘探向大位移井、深井、超深水井等方向发展,高温储层段对钻井液处理剂的要求也越来越高。增黏剂作为控制无土相水基钻井液黏度和提高钻井液携岩能力的关键材料,其抗温能力也面临着更高的挑战。以2-丙烯酰胺-2-甲基丙磺...近年来,随着石油勘探向大位移井、深井、超深水井等方向发展,高温储层段对钻井液处理剂的要求也越来越高。增黏剂作为控制无土相水基钻井液黏度和提高钻井液携岩能力的关键材料,其抗温能力也面临着更高的挑战。以2-丙烯酰胺-2-甲基丙磺酸AMPS、烯基己内酰胺NVCL、N-乙烯基吡咯烷酮NVP、二乙烯苯DVB这4种合成单体为原料,以油溶性偶氮类为引发剂,通过胶束聚合反应,研制了一种水基抗温增黏剂,并评价了其各项性能,结果表明:该抗温增黏剂于160℃老化后,0.9%样品溶液的表观黏度为34 m Pa·s,动塑比达0.55,具有良好的增黏提切效果。该剂抗温达180℃,在高温下的增黏效果优于常规增黏剂,抗盐达饱和,抗钙达1.5%,很好地满足了钻井过程中对高温高盐地层钻井液增黏提切的要求。展开更多
A comprehensive understanding of the distribution and water movement of the substrate in root areas is crucial to the design and management of drip irrigation systems,which is a significant step to maximizing crop wat...A comprehensive understanding of the distribution and water movement of the substrate in root areas is crucial to the design and management of drip irrigation systems,which is a significant step to maximizing crop water use efficiency by understanding the hydrodynamics in soilless substrates.In this study,an improved HYDRUS-2D model by the dynamic root growth model was used to simulate water movement under the condition of drip irrigation and the water uptake process of the root,and then,compared with the observed data.Substrate water content under drip irrigation was also measured with the calibrated ECH20-EC5 sensors.The situation of substrate water movement was analyzed under the conditions of different depths,different initial water content,and different irrigation amount.The substrate water movement under different drip irrigation conditions was explored.The results showed that incorporating the defined initial and boundary conditions and the hydraulic characteristics of the substrate into the model enabled HYDRUS model to predict the movement and position of water in unsaturated porous media by solving Richards equation.Under drip irrigation,the substrate wetting body was approximately a quarter ellipse,and the water would continue to move to the area where the wetting front did not reach within 1 h after irrigation.The simulation results of the improved HYDRUS-2D model agreed well with those observed by the ECH2O-EC5 sensors,and the model could provide a basis for precision irrigation of soilless substrate culture under drip irrigation.展开更多
文摘Soilless (hydroponic) vegetables and fruits grown in greenhouses are gaining popularity and potentially represent a compliment toward sustainable food sources. Only a few studies have looked at the nutrient quality of strawberries (Fragaria × ananassa) and raspberries (Rubus idaeus) grown in soilless systems. Dry weights, content of ascorbic acid, tocopherol, total polyphenolic compounds, glucose, fructose, and soluble solids (BRIX) of strawberries and raspberries grown in soilless systems were compared to their counterpart grown in soil. There was no change in dry weights but BRIX values (28% - 31%), glucose (158% - 175%), and fructose (75% - 102%) content for strawberries and raspberries respectively were significantly higher for the soil grown berries compared to soilless grown berries. Contents of ascorbic acid, tocopherol and total polyphenolic compounds were significantly higher in soilless grown strawberries compared to soil grown strawberries by 74%, 53%, and 22% respectively, and contents of ascorbic acid and total polyphenolic compounds were significantly higher in soil grown raspberries by 83% and 67% respectively compared to soilless grown raspberries. Soilless grown produce warrants future research to strive toward the potential to provide nutrient dense crops and opportunities toward optimized sustainable production.
文摘[Objective]The paper was to screen out planting mode suitable for mini-watermelon in spring greenhouses under soilless cultivation.[Method]The effects of single row planting with one main vine and one lateral vein,double row planting with one main vine and one lateral vein,and double row planting with two lateral veins on the growth period,growth,fruit quality and yield of mini-watermelon were studied.[Result]The planting mode of single row planting with one main vine and one lateral vein was adopted.The earliest date of harvest was May 28;the fruit-setting rate was 106.3%;and the single fruit weight was 1.33 kg.The lowest abnormal fruit rate was 0.73%;the highest yield was 54465.45 kg/hm^2,and the central sugar content was the highest of 12.95%.[Conclusion]Single row planting mode under soilless cultivation has certain demonstration and popularization prospect.
基金Supported by the Science and Technology Project of Beijing Municipal Bureau of Agriculture in 2018
文摘In order to screen out the small watermelon varieties with red flesh suitable for soilless cultivation and to meet people's requirements of high-quality watermelons,comparative tests were conducted on 6 small watermelon varieties with red flesh under soilless culture conditions in 2018.Based on the data of field traits,yield traits,quality traits and commercial traits,the integrated results showed that ‘Chuanqi 2’ had good quality and high yield,and the overall performance was the best.
文摘[Objective]The paper was to study the effects of different plant densities on growth,yield and quality of mini-watermelon under soilless cultivation.[Method]Five planting densities were designed under double row planting with one main vine and one lateral vein in soilless cultivation,including 5.25×10^4,3.90×10^4,3.15×10^4,2.70×10^4 and 2.25×10^4 plants/hm^2.[Conclusion]Under the planting density of 3.15×10^4 plants/hm^2,the yield of mini-watermelon was the highest of 58.719 t/hm^2;the yield of plot was the highest of 260.97 kg;the central sugar content was the highest of 13.20%;the earliest date of harvest was June 1,ranking second;the fruit setting rate was 108.9%;the single fruit weight was 1.72 kg;and the malformed fruit rate was 0.48%.[Conclusion]Under soilless cultivation,3.15×10^4 plants/hm^2 is the best planting density.
文摘Vertical cultivation is the most important method in the future spatially in smart agriculture systems. The fourth different thickness soilless textile was used as the board to cultivate water-cress (Eruca Sativa). The vacuum pump model VRI V3 Dual Stage Vacuum Pump was constructed and used in the preliminary experimental test. It’s run to measure the water content and water absorption percentage for soilless board under lab conditions. Different tests were evaluated for the absorption sample after elapsed time 0.08, 0.17, 0.25, 5, 24 and 120 hours. Soilless board textile with thickness 32 mm, 26 mm, 21 mm and 16 mm made from the following material: woven fabric of Cotton. The four mattresses of smart textile as soilless vertical cultivation, measuring 40 cm width 60 cm length were created;it has filler from soft sawdust, a mixture of red (beech) and white (Swedish) wood. The result of preliminary test illustrated that the soilless board may be able to keep the amount of water for more than 72.3% after 5 days from edit water to soilless board. The soilless smart with 32 mm thickness gave highly growths of water-cress compared with the other smart mattress.
文摘Soilless culture in China has developed rapidly in recent years. The area of soilless culture in China was about 0.1 ha in 1985, 117 ha in 1995, but in 2002 the area reached to 865 ha. This paper introduced the brief history of soilless culture in China, and the main soilless culture systems. The present situation and problems are also discussed in this paper.
基金supported by the Science and Technology Project of State Grid Corporation of China(No.5400202133157A-0-0-00)partially supported by the State Grid Gansu Electric Power Company,China。
文摘Plasma nitrogen fixation(PNF)has been emerging as a promising technology for greenhouse gasfree and renewable energy-based agriculture.Yet,most PNF studies seldom address practical application-specific issues.In this work,we present the development of a compact and automatic PNF system for on-site agricultural applications.The system utilized a gliding-arc discharge as the plasma source and employed a dual-loop design to generate NO_(x)from air and water under atmospheric conditions.Experimental results showed that the system with a dualloop design performs well in terms of energy costs and production rates.Optimal operational parameters for the system were determined through experimentation,resulting in an energy cost of 13.9 MJ mol^(-1)and an energy efficiency of 16 g kWh^(-1)for NO_(3)^(-)production,respectively.Moreover,the concentration of exhausted NO_(x)was below the emission standards.Soilless lettuce cultivation experiments demonstrated that NO_(x)^(-)produced by the PNF system could serve as liquid nitrate nitrogen fertilizer.Overall,our work demonstrates the potential of the developed PNF system for on-site application in the production of green-leaf vegetables.
文摘近年来,随着石油勘探向大位移井、深井、超深水井等方向发展,高温储层段对钻井液处理剂的要求也越来越高。增黏剂作为控制无土相水基钻井液黏度和提高钻井液携岩能力的关键材料,其抗温能力也面临着更高的挑战。以2-丙烯酰胺-2-甲基丙磺酸AMPS、烯基己内酰胺NVCL、N-乙烯基吡咯烷酮NVP、二乙烯苯DVB这4种合成单体为原料,以油溶性偶氮类为引发剂,通过胶束聚合反应,研制了一种水基抗温增黏剂,并评价了其各项性能,结果表明:该抗温增黏剂于160℃老化后,0.9%样品溶液的表观黏度为34 m Pa·s,动塑比达0.55,具有良好的增黏提切效果。该剂抗温达180℃,在高温下的增黏效果优于常规增黏剂,抗盐达饱和,抗钙达1.5%,很好地满足了钻井过程中对高温高盐地层钻井液增黏提切的要求。
基金This work was financially supported by the National Key Research and Development Program,China(Grant No.2019YFD1001903)the Fundamental Research Funds for the Central Universities(Grant No.2021TC031).
文摘A comprehensive understanding of the distribution and water movement of the substrate in root areas is crucial to the design and management of drip irrigation systems,which is a significant step to maximizing crop water use efficiency by understanding the hydrodynamics in soilless substrates.In this study,an improved HYDRUS-2D model by the dynamic root growth model was used to simulate water movement under the condition of drip irrigation and the water uptake process of the root,and then,compared with the observed data.Substrate water content under drip irrigation was also measured with the calibrated ECH20-EC5 sensors.The situation of substrate water movement was analyzed under the conditions of different depths,different initial water content,and different irrigation amount.The substrate water movement under different drip irrigation conditions was explored.The results showed that incorporating the defined initial and boundary conditions and the hydraulic characteristics of the substrate into the model enabled HYDRUS model to predict the movement and position of water in unsaturated porous media by solving Richards equation.Under drip irrigation,the substrate wetting body was approximately a quarter ellipse,and the water would continue to move to the area where the wetting front did not reach within 1 h after irrigation.The simulation results of the improved HYDRUS-2D model agreed well with those observed by the ECH2O-EC5 sensors,and the model could provide a basis for precision irrigation of soilless substrate culture under drip irrigation.