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Technologies for Efficient Use of Irrigation Water and Energy in China 被引量:1
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作者 ZHANG Qing-tao XIA Qing +1 位作者 Clark C K Liu Shu Geng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1363-1370,共8页
While the shortage of water and energy is a well-recognized worldwide natural resources issue, little attention has been given to irrigation energy efficiency. In this paper, we examine the potential energy savings th... While the shortage of water and energy is a well-recognized worldwide natural resources issue, little attention has been given to irrigation energy efficiency. In this paper, we examine the potential energy savings that can be achieved by implementing improved irrigation technologies in China. The use of improved irrigation management measures such as a flow meter, irrigation scheduling, and/or regular maintenance and upgrades, typically reduces the amount of water pumped over the course of a growing season. The total energy saved by applying these improved measures could reach 20%, as compared with traditional irrigation methods. Two methods of irrigation water conveyance by traditional earth canal and low pressure pipeline irrigation (LPPI) were also evaluated. Our study indicated that LPPI could save 6.48x 109 kWh yr1 when applied to 11 Chinese provinces. Also, the COz emission was reduced by 6.72 metric tons per year. Among these 11 surveyed provinces, the energy saving potential for two provinces, Hebei and Shandong, could reach 1.45 x 109 kWh yr^-1. Using LPPI, potential energy saved and CO2 emissions reduced in the other 20 Chinese provinces were estimated at about 2.97×109 kWh yr-1 and 2.69 metric tons per year, respectively. The energy saving potential for Heilongjiang, a major agriculture province, could reach 1.77× 109 kWh yr-1, which is the largest in all provinces. If LPPI is applied to the entire country, average annual energy saving of more than 9 billion kWh and average annual CO2 emission reduction of more than 9.0 metric tons could be realized. Rice is one of the largest users of the world's fresh water resources. Compared with continuous flooding irrigation, intermittent irrigation (ITI) can improve yield and water-use efficiency in paddy fields. The total increments of net output energy and yield by ITI in paddy fields across China could reach 2.5× 1016 calories and l07 tons, respectively. So far only a small part of agricultural land in China has adopted water and energy saving technologies. Therefore, potential water and energy savings in China by adapting improved irrigation technology could be significant and should be carefully studied and applied. 展开更多
关键词 water and energy efficiency irrigation management low pressure pipeline irrigation energy saving potential intermittent irrigation
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A study on the simulation of carbon and water fluxes of Dangxiong alpine meadow and its response to climate change 被引量:1
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作者 Lingyun He Lei Zhong +3 位作者 Yaoming Ma Yuting Qi Jie Liu Peizhen Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期22-27,共6页
The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of th... The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of the Tibetan Plateau,is a typical example.To understand the carbon and water fluxes,water use efficiency(WUE),and their responses to future climate change for the alpine meadow ecosystem in the Dangxiong area,two parameter estimation methods,the Model-independent Parameter Estimation(PEST)and the Dynamic Dimensions Search(DDS),were used to optimize the Biome-BGC model.Then,the gross primary productivity(GPP)and evapotranspiration(ET)were simulated.The results show that the DDS parameter calibration method has a better performance.The annual GPP and ET show an increasing trend,while the WUE shows a decreasing trend.Meanwhile,ET and GPP reach their peaks in July and August,respectively,and WUE shows a“dual-peak”pattern,reaching peaks in May and November.Furthermore,according to the simulation results for the next nearly 100 years,the ensemble average GPP and ET exhibit a significant increasing trend,and the growth rate under the SSP5–8.5 scenario is greater than that under the SSP2–4.5 scenario.WUE shows an increasing trend under the SSP2–4.5 scenario and a significant increasing trend under the SSP5–8.5 scenario.This study has important scientific significance for carbon and water cycle prediction and vegetation ecological protection on the Tibetan Plateau. 展开更多
关键词 Carbon and water flux water use efficiency Alpine meadow Biome-BGC model Climate change
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Yields,growth and water use under chemical topping in relations to row configuration and plant density in drip-irrigated cotton 被引量:1
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作者 Wang Xuejiao Hu Yanping +10 位作者 Ji Chunrong Chen Yongfan Sun Shuai Zhang Zeshan Zhang Yutong Wang Sen Yang Mingfeng Ji Fen Guo Yanyun Li Jie Zhang Lizhen 《Journal of Cotton Research》 CAS 2024年第2期123-136,共14页
Background Water deficit is an important problem in agricultural production in arid regions.With the advent of wholly mechanized technology for cotton planting in Xinjiang,it is important to determine which planting m... Background Water deficit is an important problem in agricultural production in arid regions.With the advent of wholly mechanized technology for cotton planting in Xinjiang,it is important to determine which planting mode could achieve high yield,fiber quality and water use efficiency(WUE).This study aimed to explore if chemical topping affected cotton yield,quality and water use in relation to row configuration and plant densities.Results Experiments were carried out in Xinjiang China,in 2020 and 2021 with two topping method,manual topping and chemical topping,two plant densities,low and high,and two row configurations,i.e.,76 cm equal rows and 10+66 cm narrow-wide rows,which were commonly applied in matching harvest machine.Chemical topping increased seed cotton yield,but did not affect cotton fiber quality comparing to traditional manual topping.Under equal row spacing,the WUE in higher density was 62.4%higher than in the lower one.However,under narrow-wide row spacing,the WUE in lower density was 53.3%higher than in higher one(farmers’practice).For machine-harvest cotton in Xinjiang,the optimal row configuration and plant density for chemical topping was narrow-wide rows with 15 plants m-2 or equal rows with 18 plants m-2.Conclusion The plant density recommended in narrow-wide rows was less than farmers’practice and the density in equal rows was moderate with local practice.Our results provide new knowledge on optimizing agronomic managements of machine-harvested cotton for both high yield and water efficient. 展开更多
关键词 Yield components Fiber quality TRANSPIRATION water use efficiency Heat ratio method(HRM)
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Effects of thinning and understory removal on water use efficiency of Pinus massoniana:evidence from photosynthetic capacity and stable carbon isotope analyses
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作者 Ting Wang Qing Xu +4 位作者 Beibei Zhang Deqiang Gao Ying Zhang Jing Jiang Haijun Zuo 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期42-53,共12页
Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and... Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management practices.In this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of China.Photosynthetic capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were insignificant.However,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water content.Understory removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water availability.In general,thinning may be an appropriate management measure to promote P.massoniana WUE to cope with seasonal droughts under future extreme climates. 展开更多
关键词 Stable carbon isotope water use efficiency THINNING Understory removal Photosynthetic capacity Needle water potential
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Water and nitrogen footprint assessment of integrated agronomic practice management in a summer maize cropping system
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作者 Ningning Yu Bingshuo Wang +3 位作者 Baizhao Ren Bin Zhao Peng Liu Jiwang Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3610-3621,共12页
The footprints of water and nitrogen(WF and NF)provide a comprehensive overview of the type and quantity of water consumption and reactive nitrogen(Nr)loss in crop production.In this study,a field experiment over two ... The footprints of water and nitrogen(WF and NF)provide a comprehensive overview of the type and quantity of water consumption and reactive nitrogen(Nr)loss in crop production.In this study,a field experiment over two years(2019 and 2020)compared three integrated agronomic practice management(IAPM)systems:An improved management system(T2),a high-yield production system(T3),and an integrated soil-crop management system(ISCM)using a local smallholder farmer’s practice system(T1)as control,to investigate the responses of WF,Nr losses,water use efficiency(WUE),and nitrogen use efficiency(NUE)to IAPM.The results showed that IAPM optimized water distribution and promoted water use by summer maize.The evapotranspiration over the whole maize growth period of IAPM increased,but yield increased more,leading to a significant increase in WUE.The WUE of the T2,T3,and ISCM treatments was significantly greater than in the T1 treatment,in 2019 and 2020respectively,by 19.8-21.5,31.8-40.6,and 34.4-44.6%.The lowest WF was found in the ISCM treatment,which was 31.0%lower than that of the T1 treatment.In addition,the ISCM treatment optimized soil total nitrogen(TN)distribution and significantly increased TN in the cultivated layer.Excessive nitrogen fertilizer was applied in treatment T3,producing the highest maize yield,and resulting in the highest Nr losses.In contrast,the ISCM treatment used a reduced nitrogen fertilizer rate,sacrificing grain yield partly,which reduced Nr losses and eventually led to a significant increase in nitrogen use efficiency and nitrogen recovery.The Nr level in the ISCM treatment was34.8%lower than in the T1 treatment while NUE was significantly higher than in the T1 treatment by 56.8-63.1%in2019 and 2020,respectively.Considering yield,WUE,NUE,WF,and NF together,ISCM should be used as a more sustainable and clean system for sustainable production of summer maize. 展开更多
关键词 integrated agronomic practice management water footprints nitrogen footprints water use efficiency nitrogen use efficiency yield
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Defining Cities by Water: Addressing Capital Misallocation in a Race to Conserve Resources
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作者 Yao Peng Li Jinze 《China Economist》 2024年第1期86-102,共17页
As part of its efforts to promote a sustainable and high-quality development,China has pledged to reduce water consumption and create a water-efficient society.On the basis of identifying the institutional root causes... As part of its efforts to promote a sustainable and high-quality development,China has pledged to reduce water consumption and create a water-efficient society.On the basis of identifying the institutional root causes of excessive capital allocation and excessive water consumption in China’s water-intensive industrial sectors,this study elaborates how the national water-efficient cities assessment contributes to optimized capital allocation.Our research shows that national water-efficient cities assessment has motivated local governments to compete for water efficiency.To conserve water,local governments regulated the entry and exit of water-intensive enterprises,discouraged excessive investments in water-intensive sectors,and phased out obsolete water-intensive capacities within their jurisdictions.This approach has resulted in mutually beneficial outcomes,including improved allocation of capital,enhanced water efficiency,and reduced emissions.This paper offers policy recommendations for establishing a water-efficient society throughout the 14^(th) Five-Year Plan(2021-2025)period by presenting empirical evidence on the policy effects of resource efficiency evaluation. 展开更多
关键词 Competitive evaluation for resource efficiency national water-efficient cities assessment capital misallocation water efficiency emissions abatement
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Effects of Water-Fertilizer Coupling on Growth Characteristics and Water Use Efficiency of Camellia petelotii Seedlings
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作者 Liangyu Luo Ru Li +2 位作者 Daocheng Ma Yijin Wang Linghui Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第11期2927-2947,共21页
Camellia petelotii(Merr.)Sealy is an endangered Chinese native species that originates from Guangxi Zhuang Autonomous Region,China.Previous research demonstrated that proper water and fertilizer treatments could impro... Camellia petelotii(Merr.)Sealy is an endangered Chinese native species that originates from Guangxi Zhuang Autonomous Region,China.Previous research demonstrated that proper water and fertilizer treatments could improve the growth and quality of Camellia species.This study uses a three-factor,five-level quadratic rotational combination experimental design to investigate the impact of water-fertilizer coupling on plant growth character-istics and the most suitable treatment for 24-month-old grafted C.petelotii seedlings.The experimental design includes irrigation levels[30%,40%,55%,70%,80%offield capacity(FC)],nitrogen application(0,2.17,5.43,8.70,10.87 g·plant^(-1)),and phosphorus application(0,0.96,2.40,3.85,4.81 g·plant^(-1)).The results indicated that:(1)Water-nitrogen and water-phosphorus interactions significantly affected ground diameter,chlorophyll content and specific leaf weight(SLW),while water-nitrogen interactions significantly affected plant height and photo-synthesis;(2)Application of nitrogen(8.70 g·plant^(-1))and phosphorus(3.85 g·plant^(-1))fertilizers under appropri-ate irrigation conditions(40%FC and 70%FC)improved growth.Applying fertilizers containing either nitrogen(10.87 g·plant^(-1))or phosphorus(4.81 g·plant^(-1))under adequate irrigation(55%FC)increased the Chl content.However,high nitrogen levels(10.87 g·plant^(-1))reduced photosynthesis.Conversely,it was enhanced under appropriate phosphorus(4.81 g·plant^(-1))when the irrigation level was 55%FC,indicating the sensitivity of C.pete-lotii seedlings to nitrogen fertilizer.(3)Under specific conditions of 40%FC or 70%FC irrigation and 8.70 g·plant^(-1) or 2.17 g·plant^(-1) nitrogen fertilizer application,3.85 g·plant^(-1) phosphorus addition boosted the SLW whereas,0.96 g·plant^(-1) phosphorus addition inhibited it.Under W=55%FC,deficiencies in either nitrogen(N=0 g·plant^(-1))or phosphorus(P=0 g·plant^(-1))significantly decreased leaf growth,affecting SLW.In summary,C.petelotii was more sensitive to nitrogen fertilizer at W=55%FC,and nitrogen deficiency inhibited C.petelotii growth in terms of ground diameter more than phosphorus deficiency.The C.petelotii seedlings performed best when treated with 55%FC,5.43 g·plant^(-1) nitrogen,2.40 g·plant^(-1) phosphorus per plant.These parameter esti-mates could optimize water and fertilizer application for C.petelotii seedlings. 展开更多
关键词 Camellia petelotii growth characteristics photosynthesis water-fertilizer coupling water use efficiency
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Regulation effects of water and nitrogen on yield,water,and nitrogen use efficiency of wolfberry
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作者 GAO Yalin QI Guangping +7 位作者 MA Yanlin YIN Minhua WANG Jinghai WANG Chen TIAN Rongrong XIAO Feng LU Qiang WANG Jianjun 《Journal of Arid Land》 SCIE CSCD 2024年第1期29-45,共17页
Wolfberry(Lycium barbarum L.)is important for health care and ecological protection.However,it faces problems of low productivity and resource utilization during planting.Exploring reasonable models for water and nitr... Wolfberry(Lycium barbarum L.)is important for health care and ecological protection.However,it faces problems of low productivity and resource utilization during planting.Exploring reasonable models for water and nitrogen management is important for solving these problems.Based on field trials in 2021 and 2022,this study analyzed the effects of controlling soil water and nitrogen application levels on wolfberry height,stem diameter,crown width,yield,and water(WUE)and nitrogen use efficiency(NUE).The upper and lower limits of soil water were controlled by the percentage of soil water content to field water capacity(θ_(f)),and four water levels,i.e.,adequate irrigation(W0,75%-85%θ_(f)),mild water deficit(W1,65%-75%θ_(f)),moderate water deficit(W2,55%-65%θ_(f)),and severe water deficit(W3,45%-55%θ_(f))were used,and three nitrogen application levels,i.e.,no nitrogen(N0,0 kg/hm^(2)),low nitrogen(N1,150 kg/hm^(2)),medium nitrogen(N2,300 kg/hm^(2)),and high nitrogen(N3,450 kg/hm^(2))were implied.The results showed that irrigation and nitrogen application significantly affected plant height,stem diameter,and crown width of wolfberry at different growth stages(P<0.01),and their maximum values were observed in W1N2,W0N2,and W1N3 treatments.Dry weight per plant and yield of wolfberry first increased and then decreased with increasing nitrogen application under the same water treatment.Dry weight per hundred grains and dry weight percentage increased with increasing nitrogen application under W0 treatment.However,under other water treatments,the values first increased and then decreased with increasing nitrogen application.Yield and its component of wolfberry first increased and then decreased as water deficit increased under the same nitrogen treatment.Irrigation water use efficiency(IWUE,8.46 kg/(hm^(2)·mm)),WUE(6.83 kg/(hm^(2)·mm)),partial factor productivity of nitrogen(PFPN,2.56 kg/kg),and NUE(14.29 kg/kg)reached their highest values in W2N2,W1N2,W1N2,and W1N1 treatments.Results of principal component analysis(PCA)showed that yield,WUE,and NUE were better in W1N2 treatment,making it a suitable water and nitrogen management mode for the irrigation area of the Yellow River in the Gansu Province,China and similar planting areas. 展开更多
关键词 water deficit growth characteristics YIELD water and nitrogen use efficiency principal component analysis
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Response of Growth and Water Use Efficiency of Spring Wheat to Whole Season CO_2 Enrichment and Drought 被引量:9
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作者 吴冬秀 王根轩 +2 位作者 白永飞 廖建雄 任红旭 《Acta Botanica Sinica》 CSCD 2002年第12期1477-1483,共7页
Whole_growing season pot experiments were conducted to examine the response of growth and water use efficiency ( WUE ) of spring wheat ( Triticum aestivum L. cv. Gaoyuan 602) to CO 2 enrichment. Wheat plants wer... Whole_growing season pot experiments were conducted to examine the response of growth and water use efficiency ( WUE ) of spring wheat ( Triticum aestivum L. cv. Gaoyuan 602) to CO 2 enrichment. Wheat plants were grown in open_top chambers (OTCs) subject to two concentrations of CO 2 ()(350 and 700 μL/L, hereafter 'ambient' and 'elevated' respectively) and three soil water levels (80%, 60% and 40% field water capacity ( FWC ), hereafter 'high soil moisture', 'medium soil moisture' and 'low soil moisture' respectively). Elevated CO 2 greatly increased leaf net photosynthesis ( Pn ) at all three soil water levels. The Pn of plants growing under elevated was 22% lower than that of plants growing at ambient when measured with the same (700 μL/L). Plant growth was enhanced by elevated throughout the growing season, with an increase of 14.8% in shoot dry weight at harvest under high soil moisture, and leaf area was increased by about 20% at all three soil water levels. Elevated in combination with high soil moisture increased the ratio of plant shoot dry weight to height by 15.7%, while this ratio was decreased by over 50% when plants were subject to drought. Elevated also increased the water use efficiency of wheat, mainly due to decreases in transpiration and cumulative consumption of water, and an increase in shoot dry weight, with the biggest value of 30% occurring at high soil water moisture level. Compared to high soil moisture, drought decreased shoot dry weight by 72% under ambient , and by 76% under elevated . Similarly, drought also reduced WUE by 19% under ambient , and 23% under elevated . Our results indicate that: (1) elevated can increase the photosynthetic rates, growth and WUE of wheat plants; (2) long_term exposure to high may result in lower photosynthetic capacity; (3) high stimulates plants lateral growth more than vertical growth; (4) the effects of CO 2 enrichment on plants depend on soil water status, with plants benefiting more from CO 2 enrichment if sufficient water is supplied; and (5) drought may cause relatively more reduction in plant growth and WUE under future elevated conditions. 展开更多
关键词 CO 2 open_top chamber water use efficiency Triticum aestivum DROUGHT
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Effects of Different Irrigation Amounts on Water Consumption and Water Use Efficiency of Greenhouse Cucumber 被引量:6
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作者 郭生虎 孔德杰 +2 位作者 张源沛 郑国宝 朱金霞 《Agricultural Science & Technology》 CAS 2010年第9期217-220,共4页
[Objective] This study was to investigate the effects of different irrigation amount on water consumption and water use efficiency of greenhouse cucumber.[Method]Under the condition of drip irrigation with different w... [Objective] This study was to investigate the effects of different irrigation amount on water consumption and water use efficiency of greenhouse cucumber.[Method]Under the condition of drip irrigation with different water amounts in sunlight greenhouse of the arid areas in Ningxia,the soil water was measured and the water consumption of crop was calculated.[Result]When irrigation amount was 563 mm,the water consumption as a whole gradually increased with the delay of growth period,reached peak during the thriving stage of fruit setting,and then gradually declined;in each treatment,the daily water consumption increased with the increasing of irrigation amount during each growth period.However,the consumption of soil moisture reduced with the significant increase of irrigation.563 mm of irrigation amount could meet the water requirements of cucumber and began to add water to soil,and water utilization efficiency could reach 33.4 kg/m3.[Conclusion]The research had provided theoretical basis for water management in the production process of greenhouse cucumber. 展开更多
关键词 GREENHOUSE CUCUMBER Irrigation amount water consumption water utilization efficiency
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Operation Effect of Water Control System for Beddings of Pig-raising Deep-litter Systems 被引量:6
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作者 林家彬 李辉 +4 位作者 汤赤 秦竹 周忠凯 刘建龙 余刚 《Agricultural Science & Technology》 CAS 2016年第4期923-926,946,共5页
[Objective] The study was conducted to optimize the operation parameters of water control equipment for deep-litter beddings. [Method] A four-factor three-level orthogonal design was adopted to optimize experimental t... [Objective] The study was conducted to optimize the operation parameters of water control equipment for deep-litter beddings. [Method] A four-factor three-level orthogonal design was adopted to optimize experimental temperature, stopping time of aeration, aeration time and aeration rate by 9 groups of experiments, so as to improve the water removal efficiency of adopted mixed and reduce operation energy consumption. [Result] The average water contents in the mixed bedding under 3 temperatures decreased by 4.58% ±2.91%, 13.17% ±3.77% and 10.8% ±7.72%, respectively; the highest water removal efficiency could be achieved under an experimental temperature at 45 ℃, stopping time of aeration of 15 min, aeration time of 7 min, and an aeration rate at 4 m^3/min, which formed the optimal factor combination mode of the operation parameter of the water control equipment; the effects of various experimental factors on water content in the bedding were in order of aeration ratetemperatureaeration timestopping time of aeration; and the effects of various experimental factors on water removal efficiency in the bedding were in order of temperatureaeration rateaeration timestopping time of aeration. [Conclusion] After the optimization of operation parameters of the water control equipment for the deep-litter bedding, water removal efficiency of the mixed bedding could be improved, and the operation energy consumption of the equipment could be reduced. 展开更多
关键词 Deep-litter bedding Pig raising water management water content water removal efficiency
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Species- and Habitat-variability of Photosynthesis, Transpiration and Water Use Efficiency of Different Plant Species in Maowusu Sand Area 被引量:105
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作者 蒋高明 何维明 《Acta Botanica Sinica》 CSCD 1999年第10期1114-1124,共11页
Photosynthesis ( P n ), transpiration ( E ) and water use efficiency ( WUE ) of more than 66 arid sand species from different environmental habitats, shifting sand dune, fixed sand dune, lowland and wetland in ... Photosynthesis ( P n ), transpiration ( E ) and water use efficiency ( WUE ) of more than 66 arid sand species from different environmental habitats, shifting sand dune, fixed sand dune, lowland and wetland in the Maowusu Sand Area were analyzed and the relation among these characteristics and the resource utilization efficiency, taxonomic categories and growth forms of the species were assessed. The results showed that species from Chenopodiaceae, Gramineae, Leguminosae which possessed the C 4 photosynthesis pathway, or C 3 pathway and also with nitrogen_fixation capacities had higher or the highest P n values, i.e., 20~30 μmol CO 2·m -2 ·s -1 , while that of evergreen shrub of Pinaceae had the lowest P n values, i.e., 0~5 μmol CO 2·m -2 ·s -1 . Those species from Compositae, Scrophulariaceae, and Gramineae with C 3 pathway but no N_fixation capacity had the highest E rates, i.e., 20~30 mmol H 2O·m -2 ·s -1 and again the evergreen shrub together with some species from Salicaceae and Compositae had the lowest E rates, i.e., 0~5 mmol H 2O·m -2 ·s -1 . Species from Leguminosae, Gramineae and Chenopodiaceae with C 4 pathway or C 3 pathway with N_fixation capacity, both shrubs and grasses, generally had higher WUE . However, even the physiological traits of the same species were habitat_ and season_specific. The values of both P n and E in late summer were much higher than those in early summer, with average increases of 26%, 40% respectively in the four habitats. WUE in late summer was, however, 12% lower. Generally, when the environments became drier as a result of habitats changed, i.e., in the order of wetland, lowland, fixed sand dune and shifting sand dune, P n and E decreased but WUE increased. 展开更多
关键词 PHOTOSYNTHESIS TRANSPIRATION water use efficiency HABITAT C 4 pathway SHRUBS Grasses Maowusu Sand Area
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Variations in Composition and Water Use Efficiency of Plant Functional Groups Based on Their Water Ecological Groups in the Xilin River Basin 被引量:15
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作者 陈世苹 白永飞 韩兴国 《Acta Botanica Sinica》 CSCD 2003年第10期1251-1260,共10页
Major plant species in the Xilin River Basin were grouped into six plant functional groups (PFGs) based on their water ecological groups: xerophytes, mesoxerophytes, xeromesophytes, mesophytes, hygromesophytes and hyg... Major plant species in the Xilin River Basin were grouped into six plant functional groups (PFGs) based on their water ecological groups: xerophytes, mesoxerophytes, xeromesophytes, mesophytes, hygromesophytes and hygrophytes. We surveyed the composition, delta(13)C values and proline concentration of PFGs in eight different plant communities along a soil moisture gradient. Results show that: (1) PFGs occurred variously in eight steppe communities with different soil moisture status. In wetter habitats, hygromesophytes and hygrophytes were more abundant and accounted for the majority of aboveground biomass, whereas xerophytes and mesoxerophytes became more conspicuous in dryer habitats; (2) the numerical order of the mean delta(13)C values of PFGs is as follows: xerophytes (-26.38parts per thousand) = mesoxerophytes (-26.51parts per thousand) > xeromesophytes (-27.02parts per thousand) > mesophytes (-27.56parts per thousand) = hygromesophytes and hygrophytes (-27.80parts per thousand); (3) xerophytes maintained relative higher delta(13)C values and water use efficiency (WUE) in habitats of different water availability, whereas delta(13)C values of xeromesophytes were more sensitive to change in soil water availability; (4) From xerophytes to hygrophytes, their proline content markedly increased. Significantly positive correlations existed between proline and biomass or delta(13)C values of different water ecological groups. 展开更多
关键词 delta C-13 value water ecological groups soil moisture gradient water use efficiency PROLINE leaf water content (LWC)
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Water Use of Leymus chinensis Community 被引量:6
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作者 宋炳煜 杨劼 +1 位作者 旭日 乌江雨 《Acta Botanica Sinica》 CSCD 2003年第10期1245-1250,共6页
Soil moisture of Leymus chinensis (Trin.) Tzvel. community has obviously stratified phenomena: the layer (0-40 cm) in which roots are concentrically distributed is directly influenced by precipitation and evapotranspi... Soil moisture of Leymus chinensis (Trin.) Tzvel. community has obviously stratified phenomena: the layer (0-40 cm) in which roots are concentrically distributed is directly influenced by precipitation and evapotranspiration. It can be called interaction layer of precipitation and evapotranspiration. The layer (40-120 cm), where water-storage capacity exchange lagged exchange of the root-layer water-storage capacity and the community evapotranspiration, can be called major water-storage layer. The layer (under 120 cm) can be called water relatively stable/balanced layer. The year 1996 was a normal flow year, and soil water had a surplus of 18 mm at the end of the growing season. The year 1998 was a high flow year, because leakage took place under continuous heavy rainfall, soil water had a deficit of 15 mm at the end of the growing season. Transpiration to evapotranspiration ( T/ET) value reflected not only the luxuriance degree of the community, but also the water use regime of the environmental resources. T/ET value was low (0.5) in May 1998, reaching 0.7 in June, then decreasing to 0.6 in July, due to the impact of rainfall inclining, while August reached the maximum (0.9), and September decreased to 0.6. Water use efficiency (WUE) was mainly restricted by the growing rate of plants under sufficient water condition (1998). Its seasonal changes were coincident with the grand period of growth of the plants. When both meanings of WUE and T/ET were analyzed profoundly, the concept of evapotranspiration efficiency (ETE) which can all-side reflect utilization regime of the environmental water resources was advanced. 展开更多
关键词 Leymus chinensis community water use efficiency (WUE) transpiration to evapotranspiration (T/ET) evapotranspiration efficiency (ETE)
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Effects of Different Tillage Techniques on Yield and Water Use Efficiency in Broomcorn Millet 被引量:2
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作者 陈凌 乔治军 +6 位作者 王君杰 王海岗 曹晓宁 田翔 刘思辰 秦慧彬 杨光宗 《Agricultural Science & Technology》 CAS 2017年第3期432-434,437,共4页
[Objective] The effects of different tillage techniques on dry matter accu- mulation, soil water content, water use efficiency and yield of broomcom millet were studied. [Method] With Jinsu 9 as an experiment material... [Objective] The effects of different tillage techniques on dry matter accu- mulation, soil water content, water use efficiency and yield of broomcom millet were studied. [Method] With Jinsu 9 as an experiment material, the effects of deep tillage, traditional tillage and no tillage and rotary tillage on dry matter accumulation, soil water content, water use efficiency and yield of broomcom millet were investi- gated. [Result] Dry matter accumulation rate and accumulated amount were signifi- cantly higher in the deep tillage, no tillage and rotary tillage treatments than in the conventional tillage treatment, and the highest in the deep tillage treatment. The soil water content of the deep tillage treatment at 0-100 cm was higher than those of other tillage techniques, deep tillage also exhibited the highest soil water storage, and water use efficiency values were in order of deep tillage〉rotary tillage〉no tillage〉conventional tillage. The deep tillage treatment also showed the highest grain weight per spike, 1 000-grain weight and yield, while conventional tillage exhibited the lowest values, indicating that deep tillage is most beneficial to improvement of yield and water use efficiency of broomcom millet. [Conclusion] This study provides a scientific basis for water use efficiency of broomcorh millet in its main producing areas. 展开更多
关键词 Tillage techniques Broomcorn Millet water use efficiency YIELD
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Responses of the seedlings of five dominant tree species in Changbai Mountain to soil water stress 被引量:1
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作者 代力民 李秋荣 +1 位作者 王淼 姬兰柱 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期191-196,共6页
Soil water stress was studied on the potted seedlings of five dominant tree species (Pinus koraienes Sieb.et Zucc., Fraxinus mandshurica Rupr., Juglans mandshurica Maxim, Tilia amurensis Rupr. and Quercus mongolica Fi... Soil water stress was studied on the potted seedlings of five dominant tree species (Pinus koraienes Sieb.et Zucc., Fraxinus mandshurica Rupr., Juglans mandshurica Maxim, Tilia amurensis Rupr. and Quercus mongolica Fisch.ex Turcz) from the broadleaved/Korean pine forest in Changbai Mountain. Leaf growth, water transpiration and photosynthesis were compared for each species under three soil moisture conditions: 85%-100% (high water, CK), 65%-85% (Medium water, MW) and 45%-65% (low water, LW) of 37.4% water-holding capacity in field. The results showed that the characteristic of typical drought-resistance of the leaves is significantly developed. The net photosynthetic rate and water use efficiency of Fraxinus mandshurica were higher in MW than those in CK. But for the other four species, the net photosynthetic rate and water use efficiency in CK were lower than those in MW and LW. The transpiration rate responding to soil moistures varied from species to species. 展开更多
关键词 water stress Net photosynthesis Transpiration rate water use efficiency Broadleaf/Korean pine forest
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Research Advance on Influencing Factors of Crop Water Use Efficiency 被引量:3
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作者 周敏 周绍松 +2 位作者 王建新 张忠武 杨景华 《Agricultural Science & Technology》 CAS 2014年第11期1967-1976,共10页
The research advance on the influencing factors of crop water use effi-ciency (WUE) was reviewed in this paper. Based on the discussion on the conno-tation of crop WUE, the influencing factors of crop WUE, such as c... The research advance on the influencing factors of crop water use effi-ciency (WUE) was reviewed in this paper. Based on the discussion on the conno-tation of crop WUE, the influencing factors of crop WUE, such as crop, environ-ment, chemicals, cultivation measures, cropping systems, etc, were elaborated. A-mong them, the species and varieties of crop, soil and chemicals were discussed in detail. 展开更多
关键词 Crop water use efficiency Soil Influencing factor
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Suitable Date of Seeding, Planting Density and Water Use Efficiency for Propagation of Stock Seed Potato in Mountainous Region of Southwest Sichuan 被引量:2
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作者 沈学善 罗李飞 +1 位作者 李春荣 黄钢 《Agricultural Science & Technology》 CAS 2012年第9期1904-1907,共4页
[Objective] The experiment was conducted to study suitable date of seed- ing and density of spring potato at the stock breeding base in Ebian County at an elevation of 1 200 to 1 500 m. [Methods] Virus-free Potato "C... [Objective] The experiment was conducted to study suitable date of seed- ing and density of spring potato at the stock breeding base in Ebian County at an elevation of 1 200 to 1 500 m. [Methods] Virus-free Potato "Chuanyu 13" was used as material to study the effects of date of seeding and density on growing period, germination rate, yield and water use efficiency of spring potato in the field. [Result] With the postponement of date of seeding, the days from sowing to germination shortened, while the germination rate, the number of tubers per plant, the number of middle and small tubers in a group, yield and water use efficiency all increased. Planting density had no effects on the days from sowing to germination and the ger- mination rate, while the number of tubers per ptant, the number of middle and small tubers in a group, yield and water use efficiency increased significantly along with the increasing planting density. [Conclusion] At an elevation of 1 200 m to 1 250 m in Ebian County, the suitable date of seeding for potato was from February 9 to March 1, and the suitable planting density was 12×10^4 plants per hm^2, however, in the optimum planting density has not been found so that it needs further research, 展开更多
关键词 Date ofseedingi Planting density Stock seed YIELD water use efficiency
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Stable Isotope Technique——An Advanced Technology in Ascertaining Plant-Water Relations 被引量:1
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作者 邢丹 杨万荣 +3 位作者 蓬桂华 苏丹 廖芳芳 韩世玉 《Agricultural Science & Technology》 CAS 2014年第3期338-343,351,共7页
Some key terms and relevant standard related with stable isotope tech- nique were introduced, and the determination of carbon, hydrogen and oxygen, the three stable isotopes in water, as well as their isotope effect w... Some key terms and relevant standard related with stable isotope tech- nique were introduced, and the determination of carbon, hydrogen and oxygen, the three stable isotopes in water, as well as their isotope effect was discussed. Appli- cations and advances of stable isotopes were stated mainly from plant water source, water use efficiency, the most active water adsorption region in root system and water resources utilization differences among different species in plant communi- ty. In addition, some existing problems in investigating the plant-water relations by using stable isotope technique were put forward. In this study, we aimed to promote the sustainable development of stable isotope technique in the research of plant water utilization and in the field of ecology in China. 展开更多
关键词 Stable isotope Plant water source water use efficiency
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Effects of Different Irrigation Amounts on Water Consumption and Water Use Efficiency of Dripirrigated Celery
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作者 杨军 廉晓娟 +2 位作者 王艳 张余良 王正祥 《Agricultural Science & Technology》 CAS 2016年第9期2090-2095,共6页
This study aimed to investigate the effects of different irrigation amounts on water consumption and water use efficiency of celery under the condition of drip irrigation, so as to provide a scientific basis for high-... This study aimed to investigate the effects of different irrigation amounts on water consumption and water use efficiency of celery under the condition of drip irrigation, so as to provide a scientific basis for high-yielding, high-quality and highefficiency cultivation and water-saving irrigation of greenhouse celery. Total five irrigation amounts were designed, 117.5 (T1), 160.0 (T2), 202.5 (T3), 245.0 (T4) and 287.5 (CK) mm/hm2, and the effects of different irrigation amounts on yield, water consumption and water use efficiency of celery were studied by plot experiment. The results showed that at the soil depth of 0-40 cm, the soil water storages of different treatments ranked as T3's〉T4's〉CK's〉T2's〉T1's, and the celery water consumptions ranked as CK's〉T4's〉T3's〉T2's〉T1's. At the same time, the soil water storage in different treatment group declined with the growth of celery, and finally increased at the harvest period. Among different irrigation amounts, the water use effi- ciency and irrigation water use efficiency all ranked as T1's〉T2's〉T3's〉T4's〉CK's. The water consumption of celery was positively related to irrigation amount (P〈 0.01), and was negatively related to water use efficiency (P〈0.01) and irrigation water use efficiency (P〈0.05). When the irrigation amount was below 253 mm/hm2, the celery yield was positively related to irrigation amount (P〈0.01). There was also a positive correlation between celery output and irrigation amount. Compared with those of CK, the benefit of the T4 treatment group was equal, and the water consumption was reduced by 14.78%. In high-efficiency solar greenhouse, the irrigation amount of drip-irrigated celery is recommended as 245 mm/hm2. 展开更多
关键词 Drip irrigation CELERY Irrigation amount water consumption water use efficiency
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