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Research on Relationship between Recovery Ability after Drought Stress-rewatering and Water Use Efficiency of Winter Wheat Varieties
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作者 黄桂荣 张欣莹 +1 位作者 王雅静 钟秀丽 《Agricultural Science & Technology》 CAS 2017年第12期2236-2240,2245,共6页
The study aims at exploring the possibility of using the recovery ability af- ter drought stress-rewatering at vegetative growth stage as the evaluating index in water use efficiency (WUE) of winter wheat varieties.... The study aims at exploring the possibility of using the recovery ability af- ter drought stress-rewatering at vegetative growth stage as the evaluating index in water use efficiency (WUE) of winter wheat varieties. 'Jing 411 ', 'Jinmai 47' and their 34 near isogenic lines (NILs) were used as test materials. Semi-automatic rainproof shelter and the percolating pools were used for simulating drought treat- ment. After suffering severe drought stress, winter wheat crops were rewatered at early jointing stage. The biomass accumulation after rewatering was determined as recovery ability index. In the meanwhile, plant height in the end of vegetative growth stage was measured, and WUE of varieties/lines was also determined. Thereafter, the differences in recovery ability, plant height and the population WUE, together with the correlation between recovery ability and population WUE were analyzed, respectively. The results showed that there were significant differences in recovery ability among some varieties/lines. The recovery ability was affected by both geno- type and environment, and the interaction existed in these two factors. Significant differences existed in plant height and population WUE among the 34 NILs along with their parents. There was a significantly positive correlation between recovery ability and plant height of varieties/lines. Recovery ability and plant height were very significantly and positively correlated with population yield WUE respectively. The re- sults indicated that recovery ability after drought stress-rewatering could be used as an evaluating index of population WUE under drought condition. 展开更多
关键词 Drought stress-rewatering Near isogenic lines Recover ability Plantheight Water use efficiency
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Activity patterns and resource partitioning: seven species at watering sites in the Altun Mountains, China 被引量:5
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作者 XUE Yadong LI Jia +3 位作者 SAGEN Guli ZHANG Yu DAI Yunchuan LI Diqiang 《Journal of Arid Land》 SCIE CSCD 2018年第6期959-967,共9页
As part of a larger project to examine the richness and distribution of wildlife in Kumtag Desert area, we conducted camera trapping surveys during the period 2010–2012 at seven watering sites in an arid region of th... As part of a larger project to examine the richness and distribution of wildlife in Kumtag Desert area, we conducted camera trapping surveys during the period 2010–2012 at seven watering sites in an arid region of the Altun Mountains in western China. Information on activity patterns of the wild bactrian camel (Camelus ferus), kiang (Equus kiang), goitered gazelle (Gazella subgutturosa), argali (Ovis ammon), blue sheep (Pseudois nayaur), red fox (Vulpes vulpes), and wolf (Canis lupus) was obtained. We found that the wild camel, kiang, goitered gazelle, argali, and blue sheep were predominantly diurnal at watering sites, whereas red fox and wolf were nocturnal. Five herbivores partitioned the use of watering sites in a temporal manner to minimize the risk of predation by carnivores. The wild camel was the dominant herbivorous species at the watering sites. The kiang, goitered gazelle, argali, and blue sheep displayed adaptive water use by altering spatial or temporal patterns based on the presence or absence of wild camel, to minimize the risk of interspecific strife. These results are suggestive of the differences in activity patterns that might modulate water partitioning by different species, and provide insights for the development of conservation strategies for integrated species and decisions regarding water development in the Altun Mountains. 展开更多
关键词 camera trapping COMPETITION desert animal interaction watering site niche partitioning
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A Computer Program for Automatic Watering Based on Potential Evapotranspiration by Penman Method and Predicted Leaf Area in Miniature Pot Rose Production 被引量:3
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作者 YU Wen-jin Kitamura Ryo +2 位作者 Kato Katsuhiko LI Lian-hua Fukui Hirokazu 《Agricultural Sciences in China》 CAS CSCD 2010年第3期370-377,共8页
In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multi... In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multiple linear regression equation of leaf area and Penman Method. The experiments were carried out for a year in two watering experimental plots, one of which was controlled by pF value, and the other by the computer program. After comparing the results of the two plots, the following findings were obtained. In the computer program plot, the observed and predicted values of both leaf area and evapotranspiration indicated significant correlation at the 1% level, which suggested that the computer program had high prediction accuracy. In addition, no significant difference was observed between the two experimental plots with respects to the plant height, plant diameter, leaf area, leaf number, fresh weight, and dry weight, which demonstrated that the plants in the computer program plot had normal growth. On the other hand, although the number of flower buds and flowering shoots showed higher values at the end of certain cultivations in the computer program plot than those in pF value plot, we proposed that it was due to the effect of cumulative daily solar radiation in the greenhouse, rather than the watering. Thus, we have reached the conclusion that the computer program for automatic prediction of watering time point developed by this study has high applicability in miniature pot rose production. 展开更多
关键词 automatic watering leaf area miniature pot rose Penman Method program
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Effect of vacuum degree and aeration rate on sludge dewatering behavior with the aeration-vacuum method 被引量:4
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作者 Yu-feng GAO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第9期638-655,共18页
Due to large-scale dredging operations, a large amount of sludge is inevitably produced. Large areas of land are occupied when the dredged sludge is discarded in the disposal site as waste material. The sludge dewater... Due to large-scale dredging operations, a large amount of sludge is inevitably produced. Large areas of land are occupied when the dredged sludge is discarded in the disposal site as waste material. The sludge dewatering with aeration-vacuum (SDAV) method is suit for treating the sludge with high water content and high clay content in the disposal site. The water in the sludge can be discharged out. The volume of the sludge can be reduced quickly, and the recycling of the land can be accelerated by this method. Most importantly, this technique is an efficient way to deal with clogging problems when pumping water from high water content, high clay content dredged sludge. Vacuum degree range tests, the aeration rate range tests, and the influencing factors of sludge dewatering behavior tests were conducted with a self-developed SDAV model test device. Sludge samples were taken from the South-to-North Water Diversion East Line Project in Huai’an White-Horse Lake disposal site, Jiangsu Province, China. The optimal range of vacuum degree and aeration rate were obtained through the test results, and the mechanisms for how the two factors work and how they affect the sludge dewatering behavior were analyzed. The suitable vacuum degree range in SDAV is below 50 kPa, and the suitable aeration rate is about 1.0 m3/h. The low-vacuum degree contributes to reduce the ad-sorption effect of micro-channels on soil particles in filter material and to maintain the arch structures. Aeration has the effects of expansion, disturbance, changing Reynolds number, and dynamic sieve separating. The pump quantity of water per meter of filter tube (m) has different change rules as the vacuum degree changes under different aeration rates. The reason is that the formed arch structures’ conformation and permeability differ greatly under different combined-conditions of vacuum degree and aeration rate. The optimal combined-condition for dewatering the sludge is 35 kPa with 1.0 m3/h. 展开更多
关键词 High water content dredged sludge Sludge dewatering with aeration-vacuum (SDAV) Vacuum degree Aeration rate Arch structures
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Magnetic micro-particle conditioning–pressurized vertical electro-osmotic dewatering(MPEOD) of activated sludge: Role and behavior of moisture and organics 被引量:3
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作者 Xinxin Guo Xu Qian +1 位作者 Yili Wang Huaili Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第12期147-158,共12页
In this study, a magnetic micro-particle conditioning–pressurized vertical electro-osmotic dewatering(MPEOD) process with magnetic micro-particle conditioning–drainage under gravity–mechanical compression–electr... In this study, a magnetic micro-particle conditioning–pressurized vertical electro-osmotic dewatering(MPEOD) process with magnetic micro-particle conditioning–drainage under gravity–mechanical compression–electrical compression(MMPC–DG–MC–EC) stages was established to study the distribution and migration of water, extracellular polymeric substances(EPS), and other organic matter in the activated sludge(AS) matrix at each stage.Results showed that the MPEOD process could attain 53.52% water content(WC) in dewatered AS with bound water(BW) and free water(FW) reduction rates of 82.97% and 99.67%,respectively. The coagulation and time-delayed magnetic field effects of magnetic microparticles(MMPs) along the MMPC–DG–MC stages initiated the transformation of partial BW to FW in AS. EC had a coupling driving effect of electro-osmosis and pressure on BW, and the changes in pH and temperature at EC stage induced the aggregation of AS flocs and the release of partial BW. Additionally, MMPs dosing further improved the dewatering performance of AS by acting as skeleton builders to provide water passages. Meanwhile, MMPs could disintegrate sludge cells and EPS fractions, thereby reducing tryptophan-like protein and byproduct-like material concentrations in LB-EPS as well as protein/polysaccharide ratio in AS matrix, which could improve AS filterability. At EC stage, the former four Ex/Em regions of fluorescence regional integration analysis for EPS were obviously reduced, especially the protein-like substances in LB-and TB-EPS, which contributed to improvement of AS dewaterability. 展开更多
关键词 Activated sludge Magnetic micro-particle Pressurized vertical electro-osmotic dewatering Water distribution Extracellular polymeric substance Fluorescence regional integration analysis
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The Stimulating Effects of Rewatering on Leaf Area of Winter Wheat Suffering Water Stress 被引量:1
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作者 LIU Xiao-ying, LUO Yuan-pei and SHI Yuan-chun( Institute of Resources and Environments , China Agricultural University, Beijing 100094 Institute of Agrometeorology, CAAS , Beijing 100081) 《Agricultural Sciences in China》 CAS CSCD 2002年第2期177-183,共7页
After water stress at various levels and durations at different growth stages, rewatering could greatly stimulate the leaf area development of winter wheat. The results showed that the stimulation effect changed with ... After water stress at various levels and durations at different growth stages, rewatering could greatly stimulate the leaf area development of winter wheat. The results showed that the stimulation effect changed with water stress time, degree and duration. Rewatering under earlier stress had greater stimulation effect on leaf area than that under later stress. Higher stimulation effect was observed under severe water stress than that under moderate stress. Longer duration of stress resulted in low stimulation effect. In spite of the greater stimulation effect under severe and longer stress, the final leaf area in these situations was lower than that under moderate stress and shorter duration. Whenever the stress occurred, the stimulating effect was due to the increase of the leaf area of the tillers. Once the leaf on the main stem emerged during stress period, rewatering had no effect on its size, and consequently its leaf area. The stimulation of rewateirng on leaf area contributed to the final grain yield by 45% under moderate stress, and 67% under severe stress. Although the stimulation partly compensated for the loss during stress, the final leaf area and the grain yield could not reach the level without water stress. 展开更多
关键词 Water stress REwatering Winter wheat STIMULATION Leaf area YIELD
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Physico-Chemical and Bacteriological Quality of the Vegetable Watering Water in the Dschang Town, Cameroon 被引量:1
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作者 Ntangmo Tsafack Honorine Temgoua Emile Njine Thomas 《Journal of Environmental Protection》 2012年第8期949-955,共7页
Market gardening, in the swampy lowlands of the Dschangcity, plays an important role in terms of providing employment, and supply the city with fresh products. However, waterborne diseases, which occur in the city, ar... Market gardening, in the swampy lowlands of the Dschangcity, plays an important role in terms of providing employment, and supply the city with fresh products. However, waterborne diseases, which occur in the city, are both attributed to the bad quality of drinking water and sanitation practices. This work aims to characterize watering waters of crop, to assess the health risks associated with the use of these waters. Water from eleven streams and five wells used to irrigate crops were sampled and analyzed once a week for a month. Analyses focused on physico-chemical parameters (temperature, suspended matter, pH, electrical conductivity, COD, BOD5, NO-3 , Al, Fe, Cu, Ni), parasitological (helminthes eggs) and bacteriological (total coliforms, fecal coliforms, fecal streptococcus). The results show that, the physico-chemical quality of well waters generally approaches the WHO standards of crop watering water. The physico-chemical of streams waters and bacteriological quality of wells and streams waters are bad, according to WHO guide. These bad quality waters could contaminate crops, some of which are eaten raw, which is surely a cause of the outbreak of waterborne diseases in the city. The waters from streams are more affected. The pretreatment of the water before use for irrigation of vegetables is highly recommended. 展开更多
关键词 watering WATER Quality Urban Market GARDENING Sanitary Risks
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Seed Germination and Effects of Three Watering Regimes on the Growth of <i>Dialium guineense</i>(Wild) Seedlings
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作者 O. Olajide A. A. Oyedeji +1 位作者 G. S. Tom J. Kayode 《American Journal of Plant Sciences》 2014年第20期3049-3059,共11页
The effectiveness of three pre-germination treatments in breaking dormancy of the seeds of Dialum guineense and effects of three watering regimes on the growth performance of the seedlings were investigated. The pre-g... The effectiveness of three pre-germination treatments in breaking dormancy of the seeds of Dialum guineense and effects of three watering regimes on the growth performance of the seedlings were investigated. The pre-germination treatments were: soaking in hot water for 10 seconds and cooling down in cold water (T1), soaking in cold water for 24 hours (T2), soaking in running water for 48 hours (T3) and control (T4), while watering regimes include: watering once daily in the morning (W1), watering once every two days in the morning (W2) and watering once every three days in the morning (W3). The results showed that germination occurred first at 5 days after sowing (5 DAS) among the seeds soaked in cold water for 24 hours before sowing (T2), while the untreated seeds (control) took the longest period of 12 days before germination occurred. T1 had the highest germination value of 49.6% while T3 had the least of 31.2%. The effects of watering regimes were found to be significantly different on stem-collar diameter, leaf area and total dry weight (P < 0.05). The least significant difference (LSD) test showed that W2 and W3 supported the best growth performance. It is concluded from the results that T2 should be adopted for breaking the dormancy of Dialium guineense seeds and watering interval of three days would not dispose the seedlings to water-stress. 展开更多
关键词 Dialium guineense Seeds DORMANCY Pre-Germination SEEDLINGS GROWTH watering Regimes
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Responses of the Strata and Supporting System to Dewatering in Deep Excavations
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作者 肖潇 张扬清 +1 位作者 李明广 王建华 《Journal of Shanghai Jiaotong university(Science)》 EI 2017年第6期705-711,共7页
In order to prevent the inrushing caused by deep excavations, dewatering measure has to be adopted to decrease the confined water level. In this study, the responses of the strata and supporting system to dewatering i... In order to prevent the inrushing caused by deep excavations, dewatering measure has to be adopted to decrease the confined water level. In this study, the responses of the strata and supporting system to dewatering in deep excavations are investigated through numerical simulations and case studies. Coupled fluid-mechanical analyses are performed by the use of the numerical software, FLAC3 D. The responses of the ground settlement,base heave and interior columns to the excavation and dewatering are analyzed. Numerical results indicate that the dewatering measure can effectively reduce the uplift of the subsurface soil in the excavation, and decrease the vertical displacement of the supporting system. In addition, field data of two case histories show the similar responses and confirm the validation of the numerical results. Based on the analyses, dewatering in the confined aquifer is recommended as a construction method for controlling the vertical displacement of the strata and supporting system in deep excavations. 展开更多
关键词 deep excavations COLUMN confined water numerical simulation dewatering measure
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Numerical simulation of dewatering thick unconsolidated aquifers for safety of underground coal mining 被引量:16
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作者 HANG Yuan ZHANG Gai-ling YANG Guo-yong 《Mining Science and Technology》 EI CAS 2009年第3期312-316,共5页
With an increase of mining the upper limits under unconsolidated aquifers, dewatering of the bottom aquifer of the Quaternary system has become a major method to avoid water and sand inrushes.In the 8th District of th... With an increase of mining the upper limits under unconsolidated aquifers, dewatering of the bottom aquifer of the Quaternary system has become a major method to avoid water and sand inrushes.In the 8th District of the Taiping Coal Mine in south-western Shandong province, the bottom aquifer of the Quaternary system is moderate to excellent in water-yielding capacity.The base rock above the coal seam is very thin in the concealed coal field of the Carboniferous and Permian systems.Therefore, a comprehensive dewatering plan from both the ground surface and the panel was proposed to lower the groundwater level in order to ensure mining safety.According to the hydrogeologic conditions of the 8th District, we established a numerical model so that we could simulate the groundwater flow in the dewatering process.We obtained the simulation parameters from previous data using backward modeling, such as the average coefficient of permeability of 12 m/d and the elastic storage coefficient of 0.002.From the same model, we predicted the movement of groundwater and water level variables and obtained the visible effect of the dewatering project.Despite the overburden failure during mining, no water and/or sand inrush occurred because the groundwater level in the bottom aquifer was lowered to a safe water level. 展开更多
关键词 mining under water body water and sand inrush unconsolidated aquifer drainage numerical simulation
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Watering techniques and zero-valent iron biochar pH effects on As and Cd concentrations in rice rhizosphere soils,tissues and yield 被引量:11
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作者 Md Shafiqul Islam Yali Chen +6 位作者 Liping Weng Jie Ma Zulqarnain Haider Khan Zhongbin Liao Abdoul Salam Issiaka Abdoul Magid Yongtao Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第2期144-157,共14页
Zero-valent iron amended biochar(ZVIB)has been proposed as a promising material in immobilizing heavy metals in paddy fields.In this study,the impacts of p H of ZVIB(p H 6.3 and p H 9.7)and watering management techniq... Zero-valent iron amended biochar(ZVIB)has been proposed as a promising material in immobilizing heavy metals in paddy fields.In this study,the impacts of p H of ZVIB(p H 6.3 and p H 9.7)and watering management techniques(watering amount in the order of CON(control,5/72)>3/72>1-3/72>3/100>1/72,with 5/72,for example,representing irrigation given to 5 cm above soil surface in 72 hr regular interval)on As and Cd bioavailability for rice and its grain yield(Yield BR)were investigated in a pot experiment.Brown rice As(As BR)content was irrelative to the watering treatments,while significantly decreased(>50%)with the addition of both ZVIB materials.The diminutions of brown rice Cd(Cd BR)content as well as the Yield BR were highly dependent on both the soil amendment materials’p H and watering amount.Among all the watering treatments,3/72 treatment(15%less irrigation water than the CON)with ZVIB 6.3 amendment was the optimum fit for simultaneous reduction of As BR(50%)and Cd BR contents(19%)as well as for significant increment(12%)of the Yield BR.Although high pH(9.7)ZVIB application could also efficiently decrease As and Cd contents in brown rice,it might risk grain yield lost if appropriate(e.g.3/72 in our study)watering management technique was not chosen.Therefore,ZVIB would be an environmentally friendly option as an amendment material with proper selection of watering management technique to utilize As and Cd co-contaminated arable soils safely for paddy cultivation. 展开更多
关键词 Brown rice As Brown rice Cd Grain yield Paddy soils Water management Zero-valent iron biochar
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Understanding Differential Responses of Grapevine (Vitis vinifera L.) Leaf and Fruit to Water Stress and Recovery Following Re-Watering 被引量:1
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作者 Bhaskar Bondada Janani Shutthanandan 《American Journal of Plant Sciences》 2012年第9期1232-1240,共9页
Among all fruit crops of horticultural importance, grapevines (Vitis vinifera L.) stand out as the most drought tolerant crop species whose tolerance is credited to their proficiency to recover from water stress in bo... Among all fruit crops of horticultural importance, grapevines (Vitis vinifera L.) stand out as the most drought tolerant crop species whose tolerance is credited to their proficiency to recover from water stress in both the natural and vineyard growing conditions. However, information on the recovery responses is relatively scant. Studies were conducted to address this issue using potted vines of the grapevine cultivar, Cabernet Sauvignon, which was subjected to water stress and along with anatomical and ultrastructural characterizations, physiological status was assessed in healthy and water stressed vines, and following recovery via rewatering from the water stressed vines. Water stress induced wilting of leaves, drooping of tendrils, and desiccation followed by abscission of shoot tip leaving behind a brown scar at the shoot apex. The wilted leaves accumulated ABA, which correspondingly reduced stomatal conductance and leaf water potential. Upon re-watering, both these parameters made a recovery with values similar to healthy leaves. Likewise, leaf anatomical features following rewatering resembled to that of healthy leaves. In clusters, water stress caused shriveling of preveraison (unripened) berries, which regained full turgor following water resupply, whereas the postveraison (ripening) berries in the same cluster remained unaffected as evidenced by the presence of viable mesocarp cells and epicuticular wax in the form of platelets. The study revealed that shoot tip with leaf primordia was most sensitive to water stress followed by fully expanded leaves and preveraison berries, whereas the postveraison berries remained unaffected. This information could be valuable to implementing irrigation strategies towards sustaining grape production in existing vineyards experiencing episodic droughts and targeted areas prone to drought. 展开更多
关键词 ABA Berry LEAF WATER Potential WATER Stress VITIS VINIFERA
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Application of Colligative Properties in Quality Detection of Watering Raw Milk
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作者 LIN Fang-dong JIANG Zhen-ju CAO Rui 《Animal Husbandry and Feed Science》 CAS 2011年第2期42-44,共3页
[ Objective] To investigate the effects of different water amount on freezing point of raw milk. EMetbodl The freezing point of raw milk added water at different proportions was detected by SWC-LG freezing point detec... [ Objective] To investigate the effects of different water amount on freezing point of raw milk. EMetbodl The freezing point of raw milk added water at different proportions was detected by SWC-LG freezing point detector. The linear regression equation was obtained. The reproduc- ibility was checked. The water content in raw milk was calculated according to the standard regression curve. E Result~ When the water content changed from 0 to 10%, the freezing point of raw milk increased linearly. As evidenced by the reproducibility test, the standard deviation and rela- tive standard deviation were less than 1%. The milk concentration obtained by detecting the freezing point of blind milk samples had an absolute er- ror of no more than 0.5%, compared with actual watering milk concentration. [ ConcluMonl Water content in raw milk can be determined by measur- ing freezing point, and this method is reliable and reproducible. 展开更多
关键词 Raw milk Freezing point Water content
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Stomatal Conductance, Growth and Yield of Pelargonium sidoides DC. in Response to Watering Frequency and Terminal Water Stress
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作者 Motiki Meshack Mofokeng Hintsa Tesfamichael Araya +1 位作者 Phatu William Mashela Christian Phillipus du Plooy 《Journal of Agricultural Science and Technology(A)》 2017年第8期513-521,共9页
Water is an important factor affecting growth, yield and distribution of different species. Plant response to water deficit can be in the form of physiological disorders, such as reduction in transpiration or assimila... Water is an important factor affecting growth, yield and distribution of different species. Plant response to water deficit can be in the form of physiological disorders, such as reduction in transpiration or assimilating partitioning to root growth. Sustainable use of water has become a priority in agriculture and thus innovative irrigation management practices are critical. The study aimed at investigating how watering frequency and terminal water stress influence growth of Pelargonium sidoides, an important medicinal plant in Southern Africa. The trial was a randomized complete block design with three replicates, and treatment factors were watering frequency (everyday, twice and once a week) and terminal water stress (no watering four weeks before harvesting, no watering two weeks before harvesting and no terminal stress). There was an interacting effect of watering frequency and terminal water stress on biomass and fresh root yield. More frequent watering resulted in significantly higher biomass and fresh root yield, compared to other treatments. Watering everyday with terminal or no terminal water stress resulted in higher fresh root yield, compared to other watering treatments with terminal water stress. Plant height and leaf area were significantly affected by watering frequency and terminal water stress, respectively. A significant drop in stomatal conductance of plants watered everyday was observed 240 d after treatment implementation, such that there was no significant difference across all the three watering frequency treatments. In conclusion, farmers can save on irrigation costs by reducing watering frequency, as there was no significant difference on dry root yield. 展开更多
关键词 African geranium irrigation water stress stomatal aperture root yield drought tolerance.
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基于Water Bomb折纸结构的软体机器鱼设计与性能分析
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作者 张宇 楚凯 +3 位作者 舒申 王家梁 周浩 胡俊峰 《工程设计学报》 北大核心 2025年第3期326-333,共8页
目前,以刚性材料为主体制作的机器鱼在水中具有良好的控制精度和较快的游动速度,但由于刚性材料自身的刚度较高,机器鱼通常无法很好地适应水中的狭窄通道。为了解决上述问题,将折纸结构应用于机器鱼的结构设计,设计了一种可在水中通过... 目前,以刚性材料为主体制作的机器鱼在水中具有良好的控制精度和较快的游动速度,但由于刚性材料自身的刚度较高,机器鱼通常无法很好地适应水中的狭窄通道。为了解决上述问题,将折纸结构应用于机器鱼的结构设计,设计了一种可在水中通过狭窄通道且具有良好游动性能的软体机器鱼。该机器鱼由头部、躯干和尾部组成,其中:躯干部分采用Water Bomb折纸结构,利用折纸结构的收缩和膨胀来实现躯干部分的径向变化;尾部利用软体折纸驱动器的弯曲来实现摆动,从而实现机器鱼的前行和转弯。通过实验测得了机器鱼在水箱中的运动情况,其最高游动速度为72.67 mm/s,最快转向速度为10.67 (°)/s,且能在最大负载为150 g的条件下稳定运动。结果表明,所设计的机器鱼不仅可以在水中灵活运动,而且能够利用躯干部分的折叠特性通过部分狭窄通道和障碍。这为软体机器鱼的设计与研究提供了一种新思路。 展开更多
关键词 软体机器鱼 软体折纸驱动器 Water Bomb折纸结构 折叠特性
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Environmentally sustainable groundwater control during dewatering with barriers:A case study in Shanghai 被引量:3
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作者 Zhi-Fei Xie Shui-Long Shen +1 位作者 Arul Arulrajah Suksun Horpibulsuk 《Underground Space》 SCIE EI 2021年第1期12-23,共12页
This paper presents a case study on groundwater control and environmental protection during a deep excavation of the foundation pit for the Liyang Road Station of Metro Line 10 in Shanghai.A three-dimensional finite e... This paper presents a case study on groundwater control and environmental protection during a deep excavation of the foundation pit for the Liyang Road Station of Metro Line 10 in Shanghai.A three-dimensional finite element simulation model was constructed to quantify the effects of a dewatering process on the environment around the excavation pit.To understand the decrease in the groundwater level around the foundation pit,the ground settlement and groundwater level were studied.During the excavation,environmental protection methods were used in the design of the optimal watering system to check its detrimental environmental effects.The effects of the diaphragm wall and horizontal barrier system were analyzed by varying their insertion depths and the resulting changes in the ground settlement and groundwater level were studied.It was found that increasing the insertion depth of the diaphragm wall reduced settlement near the excavation site but increased the construction costs.The diaphragm wall used in combination with a horizontal barrier was found to be effective in arresting the decrease in groundwater level and reducing settlement around the excavation site. 展开更多
关键词 DEwatering Horizontal barrier Diaphragm wall Ground settlement DRAWDOWN Confined water
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Spatiotemporal characteristics and influencing factors of vegetation water use efficiency on the Tibetan Plateau in 2001-2020 被引量:2
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作者 HE Chenyang WANG Yanjiao +1 位作者 YAN Feng LU Qi 《Journal of Geographical Sciences》 2025年第1期39-64,共26页
Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosyste... Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosystems.However,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain unclear.This study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–2020.Results indicated an annual mean WUE of 0.8088 gC/mm·m^(2)across the plateau,with a spatial gradient reflecting decrease from the southeast toward the northwest.Areas manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,respectively.Remarkably,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of increase.Environmental factors accounted for 70.79%of the variability in WUE.The leaf area index and temperature served as the major driving forces of WUE variation. 展开更多
关键词 water use efficiency spatiotemporal characteristic influencing factor Tibetan Plateau
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New insights into Earth's mantle conductivity and water distribution using Macao Science Satellite-1 data 被引量:2
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作者 ZhengYong Ren YiFei Xie +3 位作者 ChaoJian Chen HongBo Yao JingTian Tang Keke Zhang 《Earth and Planetary Physics》 2025年第3期595-606,共12页
Water content, whether as free or lattice-bound water, is a crucial factor in determining the Earth's internal thermal state and plays a key role in volcanic eruptions, melting phenomena, and mantle convection rat... Water content, whether as free or lattice-bound water, is a crucial factor in determining the Earth's internal thermal state and plays a key role in volcanic eruptions, melting phenomena, and mantle convection rates. As electrical conductivity in the Earth's interior is highly sensitive to water content, it is an important geophysical parameter for understanding the deep Earth water content. Since its launch on May 21, 2023, the MSS-1(Macao Science Satellite-1) mission has operated for nearly one year, with its magnetometer achieving a precision of higher than 0.5 nT after orbital testing and calibration. Orbiting at 450 kilometers with a unique 41-degree inclination, the satellite enables high-density observations across multiple local times, allowing detailed monitoring of low-latitude regions and enhancing data for global conductivity imaging. To better understand the global distribution of water within the Earth's interior, it is crucial to study internal conductivity structure and water content distribution. To this aim, we introduce a method for using MSS-1 data to estamate induced magnetic fields related to magnetospheric currents. We then develop a trans-dimensional Bayesian approach to reveal Earth's internal conductivity, providing probable conductivity structure with an uncertainty analysis. Finally, by integrating known mineral composition, pressure, and temperature distribution within the mantle, we estimate the water content range in the mantle transition zone, concluding that this region may contain the equivalent of up to 3.0 oceans of water, providing compelling evidence that supports the hypothesis of a deep water cycle within the Earth's interior. 展开更多
关键词 Macao Science Satellite-1 mantle conductivity water content
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Innovative Approaches in Water Decontamination: A Critical Analysis of Biomaterials, Nanocomposites, and Stimuli-Responsive Polymers for Effective Solutions 被引量:1
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作者 Rakesh Namdeti Gaddala Babu Rao +5 位作者 Nageswara Rao Lakkimsetty Muayad Abdullah Ahmed Qatan Doaa Salim Musallam Samhan Al-Kathiri Lakhayar Amer Al Amri Noor Mohammed Said Qahoor Arlene Abuda Joaquin 《Journal of Environmental & Earth Sciences》 2025年第1期92-102,共11页
In recent years,smart materials have emerged as a groundbreaking innovation in the field of water filtration,offering sustainable,efficient,and environmentally friendly solutions to address the growing global water cr... In recent years,smart materials have emerged as a groundbreaking innovation in the field of water filtration,offering sustainable,efficient,and environmentally friendly solutions to address the growing global water crisis.This review explores the latest advancements in the application of smart materials—including biomaterials,nanocomposites,and stimuli-responsive polymers—specifically for water treatment.It examines their effectiveness in detecting and removing various types of pollutants,including organic contaminants,heavy metals,and microbial infections,while adapting to dynamic environmental conditions such as fluctuations in temperature,pH,and pressure.The review highlights the remarkable versatility of these materials,emphasizing their multifunctionality,which allows them to address a wide range of water quality issues with high efficiency and low environmental impact.Moreover,it explores the potential of smart materials to overcome significant challenges in water purification,such as the need for real-time pollutant detection and targeted removal processes.The research also discusses the scalability and future development of these materials,considering their cost-effectiveness and potential for large-scale application.By aligning with the principles of sustainable development,smart materials represent a promising direction for ensuring global water security,offering both innovative solutions for current water pollution issues and long-term benefits for the environment and public health. 展开更多
关键词 Smart Materials Water Purification NANOCOMPOSITES Stimuli-Responsive Polymers Sustainable Water Treatment
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Effects of straw incorporation on biological nitrogen fixation under continuous and intermittent flooding irrigation in a rice cropping system 被引量:2
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作者 Yanhui ZHANG Jing WANG +7 位作者 Qi LIU Haihou WANG Tianlong HU Hui WANG Zhe CHEN Liangzuo SHU Elrys S.AHMED Zubin XIE 《Pedosphere》 2025年第2期364-372,共9页
Both straw incorporation and irrigation practices affect biological nitrogen(N)fixation(BNF),but it is still unclear how straw incorporation impacts BNF under continuous(CFI)or intermittent(IFI)flooding irrigation in ... Both straw incorporation and irrigation practices affect biological nitrogen(N)fixation(BNF),but it is still unclear how straw incorporation impacts BNF under continuous(CFI)or intermittent(IFI)flooding irrigation in a rice cropping system.A15N2-labeling chamber system was placed in a rice field to evaluate BNF with straw incorporation under CFI or IFI for 90 d.The nif H(gene encoding the nitrogenase reductase subunit)DNA and c DNA in soil were amplified using real-time quantitative polymerase chain reaction,and high-throughput sequencing was applied to the nif H gene.The total fixed N in the straw incorporation treatment was 14.3 kg ha^(-1)under CFI,being 116%higher than that under IFI(6.62 kg ha^(-1)).Straw incorporation and CFI showed significant interactive effects on the total fixed N and abundances of nif H DNA and c DNA.The increase in BNF was mainly due to the increase in the abundances of heterotrophic diazotrophs such as Desulfovibrio,Azonexus,and Azotobacter.These results indicated that straw incorporation stimulated BNF under CFI relative to IFI,which might ultimately lead to a rapid enhancement of soil fertility. 展开更多
关键词 heterotrophic diazotrophs irrigation practices 15N2-labeling experiment nifH cDNA nifH DNA soil fertility water management
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