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Transpiration Rate and Leaf Water Potential as Indices for Cassava Yield in Inland Valley Ecology
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作者 M. T. Lahai I.J. Ekanayake 《Journal of Agricultural Science and Technology》 2010年第6期34-44,共11页
Differences in transpiration and leaf water potential (LWP) in relation to cassava yield were investigated along inland valley toposequence in a 4×4 Latin square design. The landrace with the highest transpirat... Differences in transpiration and leaf water potential (LWP) in relation to cassava yield were investigated along inland valley toposequence in a 4×4 Latin square design. The landrace with the highest transpiration rate and lowest LWP yielded the lowest, while TMS 91/02324 and TMS 91/02327 with intermediate rate and highest LWP yielded the highest, indicating that high transpiration rate associated with low LWP reduced yield. Transpiration was lower in the fringe with deeper water table than valley bottom at deep water table site, while at shallow water table, it was higher in the fringe than valley bottom, suggesting that drought and excess moisture reduced transpiration. LWP and water table depth correlated negatively indicating that shallow water table reduced transpiration by reducing LWP. Transpiration increased and LWP decreased as radiation, leaf temperature and vapour pressure deficit increased and differences in these microclimatic conditions caused differences in the two processes between sites, years and time of day. Under mild water stress, transpiration and LWP were higher in the afternoon than the morning, but the reverse occurred under severe stress. TMS 91/02324 and TMS 91/02327 had the highest LWP under severe stress, indicating their higher drought tolerance than the other cultivars. 展开更多
关键词 transpiration rate leaf water potential root yield cassava cultivars water table depth weather condition inland valley ecology.
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A drought resistance index to select drought resistant plant species based on leaf water potential measurements 被引量:4
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作者 SayedJamaleddin KHAJEDDIN SayedHamid MATINKHAH Zahra JAFARI 《Journal of Arid Land》 SCIE CSCD 2019年第4期623-635,共13页
The water deficit in arid and semi-arid regions is the primary limiting factor for the development of urban greenery and forestation. In addition, planting the species that consume low levels of water is useful in ari... The water deficit in arid and semi-arid regions is the primary limiting factor for the development of urban greenery and forestation. In addition, planting the species that consume low levels of water is useful in arid and semi-arid regions that have poor water management measures. Leaf water potential(Ψ) is a physiological parameter that can be used to identify drought resistance in various species. Indeed, Ψ is one of the most important properties of a plant that can be measured using a pressure chamber. Drought avoiding or drought resistant species have a lower Ψ than plants that use normal or high levels of water. To determine drought resistance of species that are suitable for afforestation in arid urban regions, we evaluated twenty woody species in the Isfahan City, central Iran. The experimental design was random split-split plots with five replications. The species were planted outdoor in plastic pots and then subjected to treatments that consisted of two soil types and five drip irrigation regimes. To evaluate the resistance of each species to drought, we used the Ψ and the number of survived plants to obtain the drought resistance index(DRI). Then, cluster analysis, dendrogram, and similarity index were used to group the species using DRI. Result indicates that the evaluated species were classified into five groups:(1) high water consuming species(DRI>–60 MPa);(2) above normal water consuming species(–60 MPa≥DRI>–90 MPa);(3) normal water consuming species(–90 MPa≥DRI>–120 MPa);(4) semi-drought resistant species(–120 MPa≥DRI>–150 MPa);and(5) drought resistant species(DRI≤–150 MPa). According to the DRI, Salix babylonica L., Populus alba L., and P. nigra L. are high water consuming species, Platanus orientalis L. and Albizia julibrissin Benth are normal water consuming species, and Quercus infectoria Oliv. and Olea europaea L. can be considered as drought resistant species. 展开更多
关键词 DROUGHT RESISTANT species DROUGHT resistance index forestation leaf water potential water DEFICIT
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Effects of Different Levels of Water Stress on Leaf Water Potential,Stomatal Resistance,Protein and Chlorophyll Content and Certain Anti-oxidative Enzymes in Tomato Plants 被引量:21
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作者 Hatem Zgalla Kathy Steppe Raoul Lemeur 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2006年第6期679-685,共7页
A greenhouse experlment was performed In order to Investigate the effects of dlfferent levels of water stress on leaf water potentlal (ψw), stomatal resistance (rs), protein content and chlorophyll (Chl) conten... A greenhouse experlment was performed In order to Investigate the effects of dlfferent levels of water stress on leaf water potentlal (ψw), stomatal resistance (rs), protein content and chlorophyll (Chl) content of tomato plants (Lycoperslcon esculentum Mill. cv. Nlkita). Water stress was Induced by addlng polyethylene glycol (PEG 6 000) to the nutrlent solution to reduce the osmotlc potential (ψs). We Investlgated the behavlor of antl-oxldant enzymes, such as catalase (CAT) and superoxide dlsmutase (SOD), durlng the development of water stress. Moderate and severe water stress (i.e. ψs= -0.51 and -1.22 MPa, respectlvely) caused a decrease In ψw for all treated (water-stressed) plants compared with control plants, wlth the reductlon belng more pronounced for severely stressed plants. In addltion, rs was slgnlflcantly affected by the Induced water stress and a decrease in leaf soluble protelns and Chl content was observed. Whereas CAT actlvlty remained constant, SOD actlvlty was increased in water-stressed plants compared wlth unstressed plants. These results Indicate the possible role of SOD as an anti-oxidant protector system for plants under water stress condltlons. Moreover, It suggests the possibllity of using this enzyme as an addltional screening crlterlon for detecting water stress in plants. 展开更多
关键词 CATALASE CHLOROPHYLL drought Lycopersicon esculentum oxidative stress stomatal resistance superoxide dismutase water potential water stress.
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Hydraulic resistance partitioning between shoot and root system and plant water status of Haloxyolon ammodendron growing at sites of contrasting soil texture 被引量:4
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作者 Xu, GuiQing Li, Yan Zou, Ting 《Journal of Arid Land》 SCIE 2010年第2期98-106,共9页
Hydraulic resistance components and water relations were studied on Haloxyolon ammoden-dron,a small xeric tree,growing at sites significantly differed in soil texture.Soil water content,leaf water potential(ψl),xylem... Hydraulic resistance components and water relations were studied on Haloxyolon ammoden-dron,a small xeric tree,growing at sites significantly differed in soil texture.Soil water content,leaf water potential(ψl),xylem water potential(ψx),root water potential(ψroot),leaf transpiration rate(TR) and stomatal conductance(gs) were measured at the two sites during the growing season of 2005 and 2006.Leaf spe-cific hydraulic resistance(Rplant) during the whole growing season,hydraulic resistance of plants(Rp),shoots(Rshoot) and roots(Rroot) in the August of both years were calculated and expressed on leaf area basis.The results showed the proportion of the hydraulic resistance of the aerial part(Rshoot) to the Rp was the same to the proportion of the hydraulic resistance of the soil part(Rroot) to the Rp,indicating that both parts were equivalent important to plant water hydraulic system from soil to leaf.Positive significant corre-lations were found between Rp and Rroot,suggesting that root hydraulics resistance was a major determinant of plant hydraulic resistance(Rp) and transpiration rate.The integrated effect of stomatal control,hy-draulic regulation and morphology adjustment enabled plants at heavy soil site surviving the extreme water deficit period. 展开更多
关键词 hydraulic architecture leaf water potential transpiration hydraulic resistance stomatal conductance hydraulic limitation
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Effects of Water Stress on Leaf Water and Chlorophyll Fluorescence Parameters of Sugarcane Seedling 被引量:11
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作者 朱理环 邢永秀 +4 位作者 杨丽涛 李杨瑞 杨荣仲 莫磊兴 Li-huan Yong-xiu Li-tao Yang-rui Rong-zhong Lei-xing 《Agricultural Science & Technology》 CAS 2010年第5期17-21,共5页
[Objective] The aim was to explore the effects of water stress on leaf water and chlorophyll fluorescence parameters of sugarcane seedling,as well as to provide basis for the study on sugarcane production and evaluati... [Objective] The aim was to explore the effects of water stress on leaf water and chlorophyll fluorescence parameters of sugarcane seedling,as well as to provide basis for the study on sugarcane production and evaluation. [Method] Seven different sugarcane varieties were studied at the seedling stage under drought stress,and the changes of leaf water and chlorophyll fluorescence parameters under stress conditions were detected. [Result] leaf water potential,leaf relative water content and soil relative water content showed a certain amount of internal relationship,the sugarcane varieties that had more tolerant to drought had higher utilization rate of soil water; the correlation analysis and factor analysis suggested that the survival rate at seedling stage under drought stress,Fv/Fm,leaf water potential and relative water content could be used as drought resistance evaluation indicators. [Conclusion] As a relatively independent influencing factor,water potential had dominating effect on drought resistance,and the reliability of Fv/Fm as drought resistance evaluation indicator had been verified. 展开更多
关键词 Sugarcane Drought stress Leaf water Leaf relative water content Fv/Fm
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Water adaptive traits of deep-rooted C_3 halophyte(Karelinia caspica(Pall.) Less.) and shallow-rooted C_4 halophyte(Atriplex tatarica L.) in an arid region,Northwest China
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作者 Yuan FAN PinFang LI +3 位作者 ZhenAn HOU TuSheng REN ChunLian XIONG Biao ZHANG 《Journal of Arid Land》 SCIE 2012年第4期469-478,共10页
This paper focused on the water relations of two halophytes differing in photosynthetic pathway, phe- notype, and life cycle: Karelinia caspica (Pall.) Less. (C3, deep-rooted perennial Asteraceae grass) and Atrip... This paper focused on the water relations of two halophytes differing in photosynthetic pathway, phe- notype, and life cycle: Karelinia caspica (Pall.) Less. (C3, deep-rooted perennial Asteraceae grass) and Atriplex tatarica L. (C4, shallow-rooted annual Chenopodiaceae grass). Gas exchange, leaf water potential, and growth characteristics were investigated in two growing seasons in an arid area of Xinjiang to explore the physiological adaptability of the two halophytes. Both K. caspica and A. tatarica showed midday depression of transpiration, in- dicating that they were strong xerophytes and weak midday depression types. The roots of A. tatarica were con- centrated mainly in the 0-60 cm soil layer, and the leaf water potential (~L) increased sharply in the 0-20 cm layer due to high soil water content, suggesting that the upper soil was the main water source. On the other hand, K. caspica had a rooting depth of about 1.5 m and a larger root/shoot ratio, which confirmed that this species uptakes water mainly from deeper soil layer. Although A. tatarica had lower transpiration water consumption, higher water use efficiency (WUE), and less water demand at the same leaf water potential, it showed larger water stress impact than K. caspica, indicating that the growth of A. tatarica was restricted more than that of K. caspica when there was no rainfall recharge. As a shallow-rooted C4 species, A. tatarica displayed lower stomatal conductance, which could to some extent reduce transpiration water loss and maintain leaf water potential steadily. In contrast, the deep-rooted C3 species K. caspica had a larger root/shoot ratio that was in favor of exploiting groundwater. We concluded that C3 species (K. caspica) tapes water and C4 species (A. tatarica) reduces water loss to survive in the arid and saline conditions. The results provided a case for the phenotype theory of Schwinning and Ehleringer on halophytic plants. 展开更多
关键词 Karelinia caspica Atriplex tatarica root/shoot ratio leaf water potential stomatal conductance transpiration
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Photosynthetic Water Use Efficiency of Heritage and Modern Potatoes under Limited and Unlimited Water Environments
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作者 Isaac R. Fandika Peter D. Kemp +1 位作者 James P. Millner Dave Horne 《Agricultural Sciences》 2014年第14期1501-1512,共12页
Photosynthetic capacity for heritage (Taewa) and modern potato cultivars were compared at different water and nitrogenregimes in the glasshouse and field. The glasshouse was 2*2*4 factorial design with two irrigation:... Photosynthetic capacity for heritage (Taewa) and modern potato cultivars were compared at different water and nitrogenregimes in the glasshouse and field. The glasshouse was 2*2*4 factorial design with two irrigation: 100% ET and 60% ET;two applied N: 50 kg N ha-1 and 200 kg N ha-1, two Taewa (Moe Moe, Tutaekuri) and two modern potatoes (Moonlight, Agria). The 2009/2010 field experiment was a split-plot, with irrigation and rain-fed regimes as the main treatments: four potatoes above were sub-treatments. The 2010/2011 field experiment was a split-split-plot, with three water regimes as the main treatments: three cultivars (Moe Moe, Tutaekuri, and Agria) were subplots;two N rates were sub-sub-treatments. Gaseous exchange was measured by CIRAS-2 at different days from emergence. Leaf water potential was measured using pressure chamber method. Taewa achieved high photosynthetic WUE in glasshouse and 2010/2011 experiment by maintaining high An, low gs and low Ci compared to modern cultivars (p The An, gs and T increased with irrigation and N increase while decreasing Ci (p < 0.01). Water stress significantly increased VPD resulting in low An and photosynthetic WUE in Moonlight in the glasshouse. The leaf water potential for Taewa was very tolerant while modern potatoes were weakened by water stress. The study indicated that Taewa can be scheduled at partial irrigation without more detrimental effects on photosynthetic capacity while modern potatoes need full irrigation to avoid detrimental effects on photosynthetic capacity. 展开更多
关键词 Taewa Photosynthesis STOMATAL Conductance (gs) transpiration (T) Irrigation Internal Carbon concentration (Ci) Vapour Pressure Deficit (VPD) Leaf water potential and PHOTOSYNTHETIC water Use Efficiency (Photosynthetic WUE) SOLANUM TUBEROSUM SOLANUM andigena
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Corrosion in Tap Water and Hot Water Supply Facilities of Stainless Steel Type 304 Pipes
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作者 Noriyuki Tanaka Shigeru Sato +2 位作者 Ippei Watanabe Yutaka Yamada Osamu Sakurada 《Materials Sciences and Applications》 2018年第1期68-80,共13页
We performed corrosion case study and corrosion tests to assess the corrosion resistance of stainless steel type 304 pipes in tap water and hot water facilities. Circulating test equipment used for corrosion tests and... We performed corrosion case study and corrosion tests to assess the corrosion resistance of stainless steel type 304 pipes in tap water and hot water facilities. Circulating test equipment used for corrosion tests and two types of sample, plates and straight pipe specimens, were examined under different conditions of residual chlorine concentration in the test water. The results of case study analysis indicated that high degrees of pitting corrosion occurred on straight pipes with inner diameter < 50 mm. The results of corrosion tests showed that the residual chlorine concentration around the pitting corrosion of stainless steel type 304 was greater than 0.3 mg/L in the plate, regardless of the remaining chlorine concentration in the straight pipe specimens. These results suggest that straight pipes have higher corrosion susceptibility because of bending during production. 展开更多
关键词 STAINLESS Steel CORROSION resistance TAP water RESIDUAL CHLORINE CORROSION potential
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Investigation of Soil Aggressiveness towards Underground Fuel Storage Tanks and Water Pipelines in Parts of Bayelsa State, Southern Nigeria
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作者 Kenneth S. Okiongbo Edirin Akpofure 《Engineering(科研)》 2012年第11期761-767,共7页
Structural failure of buried cast/ductile iron water mains and tanks due to corrosion attacks manifests in leaks and is common in most cities throughout Nigeria. The appropriate corrective action, which aims to restor... Structural failure of buried cast/ductile iron water mains and tanks due to corrosion attacks manifests in leaks and is common in most cities throughout Nigeria. The appropriate corrective action, which aims to restore pipe/tank integrity is usually based on proper understanding of the degree of corrosiveness of the soil. In an attempt to determine the potential corrosiveness of the soil to buried metallic structures in Bayelsa State, surface geoelectrical sounding was carried out. Twenty-five Schlumberger Vertical Electrical Soundings (VES) was carried out in the freshwater and meander belt geomorphic zone and the salt water mangrove swamp and estuary complex of the state using a maximum current electrode separation ranging from 200 - 400 m. The data obtained was interpreted by computer iterative modeling using a 1D inversion technique software (1X1D, Interpex, USA). The results show a high degree of heterogeneity, both laterally and vertically, which is typical of a complex depositional environment. Generally, the sub-soil condition within the expected depth of installation of water mains and storage tanks (0 - 10 m) is slightly or moderately aggressive (effective aggressivity) in the freshwater and meander belt geomorphic zone but is very strongly aggressive in the salt water mangrove swamp and estuary complex. Corrosion cells which may lead to significant corrosion failures may occur in the vicinities of strongly aggressive stations. This poses a significant corrosion risk to metallic water pipes and storage tanks. Current day design should therefore either mandate the use of a non-metallic piping product (water mains) or cathodic protection system. Prediction of potential corrosiveness of a soil and thus the application of proper corrosion control measures will not only protect the environment from spillages but will also avert cost of repair, clean-up and replacement. 展开更多
关键词 SOIL CORROSIVITY potential water Pipelines SOIL Aggressivity Electrical RESISTIVITY Cathodic Protection
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Prospects for High-quality Development of Water Resources
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作者 Liusheng PENG 《Meteorological and Environmental Research》 CAS 2021年第6期43-47,52,共6页
The water resources of rivers and reservoirs with a five-meter drop are used to discuss the technical theory and the cost and practical value of equipment cases.The high-quality development technology of water resourc... The water resources of rivers and reservoirs with a five-meter drop are used to discuss the technical theory and the cost and practical value of equipment cases.The high-quality development technology of water resources explored in this paper provides a feasible plan for achieving the goal of innovation to zero. 展开更多
关键词 Flood control Drought resistance Energy storage Low-head high-efficiency power generation High-speed water transfer channel Sewage treatment by vertical pipeline pressurization
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Drought Tolerance and Recovery of the Sedge Carex planostachys (Cyperaceae) from Central Texas Woodlands
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作者 E. Rob Wayne Oscar William Van Auken 《American Journal of Plant Sciences》 CAS 2024年第9期746-765,共20页
Carex planostachys Kunze (Cyperaceae, Cedar sedge) is an herbaceous species in a genus commonly inhabiting mesic or hydric habitats. Carex planostachys is found in arid and semi-arid Juniperus woodlands. Arid conditio... Carex planostachys Kunze (Cyperaceae, Cedar sedge) is an herbaceous species in a genus commonly inhabiting mesic or hydric habitats. Carex planostachys is found in arid and semi-arid Juniperus woodlands. Arid conditions impose survival challenges to plants in dry areas. Some plants have plasticity responses to soil water content and continued normal though reduced functions through droughts, but most herbaceous plants do not survive. Limited previous studies have suggested C. planostachys is tolerant of drought. Physiological responses of C. planostachys from Juniperus woodlands was examined is this study to determine how long plants could survive without water and if they are capable of recovery from very negative water potentials beyond what is considered the permanent wilting point for most herbaceous plants. Plants were placed in pots in partial shade in this experiment. Water loss from the soil with plants was an inverse 2nd order polynomial function with soil water decreasing from 32% to 8% by day 28 of the study. Leaf water potential was also an inverse 2nd order polynomial function but did not decline significantly until 14 days without watering. Leaf water potential was −10.0 MPa after 35 days without watering. Non-watered plants Anet, (photosynthetic rate) was significantly lower compared to the water treatment by day 21 as was stomatal conductance and transpiration. When non-watered plants were watered after 21, 28 or 35 days, full recovery of physiological responses occurred within 7 days. The length of time that C. planostachys was able to withstand drought was greater than the annual trends in lack of precipitation during springtime in this area. Carex planostachys can photosynthesize at water stress between −8 and −10 MPa. Carex planostachys drought and shade tolerance enables it to occupy an understory niche devoid of other herbaceous plants. 展开更多
关键词 CO2 Uptake Conductance Gas Exchange Photosynthesis Respiration transpiration water Stress water potential.
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The Dynamic Study on Transpiration Consumption of Black Locust Forest 被引量:2
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作者 贺康宁 侯振宏 《Forestry Studies in China》 CAS 2001年第2期10-17,共8页
To know the annual water consumption of forest, it is necessary to acquire the annual transpiration value of stands. This paper is based on the data measured in the typical weather of the growth season, from 1998 to 2... To know the annual water consumption of forest, it is necessary to acquire the annual transpiration value of stands. This paper is based on the data measured in the typical weather of the growth season, from 1998 to 2000, with the LI 1600 Steady Porometer and the general weather information. The daily variation of transpiration in black locust forest ( Robinia pesudoacacia L.) is modeled by Penman Monteith equation. As a result of the model, a continuous daily transpiration in the growth season was calculated. The net radiation, intercepted by black locust forest canopy, was acquired from a semi empirical equation of measuring net radiation R n with the extinction coefficient k and leaf area index LAI . The canopy integral stomatic resistance is a mimesis with an empirical equation of measuring data. Compared with measuring data, the relative error of the modeled ones is less than 12% averagely. At last, the total transpiration of black locust forest during the period of 1998 and 2000 in the growth season of May to October, as an average transpiration of the different density stands, were 192 46, 187 07 and 195 59?mm respectively. 展开更多
关键词 black locust transpiration net radiation leaf area index extinction coefficient stomatic resistance water consumption
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基于生态网络的黄河上游(四川段)水源涵养生态安全格局构建
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作者 刘世梁 王清波 +3 位作者 缪驰远 董玉红 孙永秀 于璐 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期418-426,共9页
在对黄河上游四川段水源涵养功能及修复潜力评估的基础上,利用形态学空间格局分析法(MSPA)识别黄河上游四川段生态源地,运用最小累积阻力模型识别生态廊道.结果表明:整个研究区水源涵养能力由南至北逐渐降低,水源涵养修复潜力等级高的... 在对黄河上游四川段水源涵养功能及修复潜力评估的基础上,利用形态学空间格局分析法(MSPA)识别黄河上游四川段生态源地,运用最小累积阻力模型识别生态廊道.结果表明:整个研究区水源涵养能力由南至北逐渐降低,水源涵养修复潜力等级高的区域主要分布在研究区域北部;MSPA识别的核心区主要位于若尔盖县和石渠县,占总面积的44.04%,形成由3个等级的生态源地和3个等级的生态廊道组成的黄河上游四川段生态安全格局;整个生态网络均集中于研究区中北部,东西部和南部生态网络分布较少.基于生态网络进行生态安全格局的构建,可为黄河上游四川段水源涵养生态修复布局提供重要依据. 展开更多
关键词 水源涵养 修复潜力 形态学空间格局分析法(MSPA) 最小累积阻力(MCR)模型 生态网络
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Selection of water source for water transfer based on algal growth potential to prevent algal blooms 被引量:7
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作者 Yongjun Song Jing Qi +3 位作者 Le Deng Yaohui Bai Huijuan Liu Jiuhui Qu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第5期246-254,共9页
Water transfer is becoming a popular method for solving the problems of water quality deterioration and water level drawdown in lakes. However, the principle of choosing water sources for water transfer projects has m... Water transfer is becoming a popular method for solving the problems of water quality deterioration and water level drawdown in lakes. However, the principle of choosing water sources for water transfer projects has mainly been based on the effects on water quality, which neglects the influence in the variation of phytoplankton community and the risk of algal blooms. In this study, algal growth potential(AGP) test was applied to predict changes in the phytoplankton community caused by water transfer projects. The feasibility of proposed water transfer sources(Baqing River and Jinsha River) was assessed through the changes in both water quality and phytoplankton community in Chenghai Lake, Southwest China. The results showed that the concentration of total nitrogen(TN) and total phosphorus(TP) in Chenghai Lake could be decreased to 0.52 mg/L and 0.02 mg/L respectively with the simulated water transfer source of Jinsha River. The algal cell density could be reduced by 60%, and the phytoplankton community would become relatively stable with the Jinsha River water transfer project, and the dominant species of Anabaena cylindrica evolved into Anabaenopsis arnoldii due to the species competition. However, the risk of algal blooms would be increased after the Baqing River water transfer project even with the improved water quality. Algae gained faster proliferation with the same dominant species in water transfer source. Therefore, water transfer projects should be assessed from not only the variation of water quality but also the risk of algal blooms. 展开更多
关键词 water transfer water quality Phytoplankton community Algal blooms Algal growth potential Chenghai Lake
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阳光玫瑰葡萄需水量及耗水规律研究 被引量:1
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作者 崔阳慧 王莉 +2 位作者 乔月莲 师校欣 杜国强 《中国果树》 2024年第2期51-57,共7页
为了明确阳光玫瑰葡萄生长期的需水量,为葡萄园节水灌溉提供理论依据,以阳光玫瑰葡萄为研究对象,通过调查生产上有效降雨量,计算水分盈亏量,在水分盈亏量的基础上设计3个灌水量处理(1 500、2 250、3 000 m^(3)/hm^(2)),研究不同灌水量... 为了明确阳光玫瑰葡萄生长期的需水量,为葡萄园节水灌溉提供理论依据,以阳光玫瑰葡萄为研究对象,通过调查生产上有效降雨量,计算水分盈亏量,在水分盈亏量的基础上设计3个灌水量处理(1 500、2 250、3 000 m^(3)/hm^(2)),研究不同灌水量对葡萄叶水势、树冠覆盖率、叶面积系数、果实品质和耗水特性的影响,确定葡萄需水量,并揭示其耗水规律。结果表明:在2 250、3 000 m^(3)/hm^(2)灌水量处理下,果实可溶性糖含量、可溶性固形物含量、固酸比均无显著性差异,但均显著高于1 500 m^(3)/hm^(2)灌水量处理;在2 250 m^(3)/hm^(2)灌水量下既不影响果实品质,又能节水;不同灌水量下葡萄耗水规律为果实膨大期>果实成熟期>新梢生长期>花期。综上,阳光玫瑰葡萄生长期总需水量为5 539 m^(3)/hm^(2)。 展开更多
关键词 葡萄 阳光玫瑰 叶水势 需水量 蒸发量 蒸腾量
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基于热传递减法集对势的区域水资源承载力评价 被引量:1
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作者 吴啸骎 吴成国 +3 位作者 秦广虎 杨振龙 赵齐雅 金菊良 《水利水运工程学报》 CSCD 北大核心 2024年第3期62-71,共10页
为有效评估区域水资源承载力系统演变特征并诊断脆弱性影响因素,引入物理学热传递思想,在集对分析传统减法集对势基础上进一步深化确定性项和不确定项之间的势差概念,构建了基于热传递减法集对势的区域水资源承载力评价方法,并应用于安... 为有效评估区域水资源承载力系统演变特征并诊断脆弱性影响因素,引入物理学热传递思想,在集对分析传统减法集对势基础上进一步深化确定性项和不确定项之间的势差概念,构建了基于热传递减法集对势的区域水资源承载力评价方法,并应用于安徽省江淮丘陵区。结果表明:2011—2018年安徽省江淮丘陵区除合肥市外,其余地市水资源承载力水平整体有所改善,合肥市水资源承载力等级较低;人均水资源量、产水模数、生态用水率等因素是影响安徽省江淮丘陵区水资源承载力变化的重要脆弱性因素。整体而言,本文计算分析结果与传统减法集对势及半偏减法集对势计算结果基本一致,这表明构建的基于热传递减法集对势的水资源承载力评价方法计算结果合理有效,且丰富和发展了集对势的内涵,可为开展区域水资源承载力评价及脆弱性因素识别提供新的研究途径。 展开更多
关键词 水资源承载力评价 减法集对势 热传递减法集对势 江淮丘陵区
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Assessment of antibiotic resistance genes in dialysis water treatment processes
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作者 Xuan Zhu Chengsong Ye +2 位作者 Yuxin Wang Lihua Chen Lin Feng 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2019年第3期185-191,共7页
Dialysis water is directly related to the safety of hemodialysis patients, thus its quality is generally ensured by a stepwise water purification cascade. To study the effect of water treatment on the presence of anti... Dialysis water is directly related to the safety of hemodialysis patients, thus its quality is generally ensured by a stepwise water purification cascade. To study the effect of water treatment on the presence of antibiotic resistance genes (ARGs) in dialysis water, this study used propidium monoazide (PMA) in conjunction with high throughput quantitative PCR to analyze the diversity and abundance of ARGs found in viable bacteria from water having undergone various water treatment processes. The results indicated the presence of 35 ARGs in the eflfluents from the different water treatment steps. Twentynine ARGs were found in viable bacteria from the effluent following carbon filtration, the highest among all of the treatment processes, and at 6.96 Log (copies/L) the absolute abundance of the cphA gene was the highest. Two resistance genes, erm (36) and mtrD-02, which belong to the resistance categories macrolides-lincosamides-streptogramin B (MLSB) and other/efflux pump, respectively, were detected in the effluent following reverse osmosis treatment. Both of these genes have demonstrated the potential for horizontal gene transfer. These results indicated that the treated effluent from reverse osmosis, the final treatment step in dialysis-water production, was associated with potential health risks. 展开更多
关键词 DIALYSIS water Treatment process Antibiotic resistance GENE HIGH-THROUGHPUT QUANTITATIVE PCR HORIZONTAL GENE TRANSFER
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六盘山华北落叶松和白桦林日蒸腾对环境因子的响应差异
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作者 张智伟 万艳芳 +5 位作者 于澎涛 白雨诗 王彦辉 刘兵兵 王晓 胡振华 《林业科学》 EI CAS CSCD 北大核心 2024年第10期29-39,共11页
【目的】准确量化半干旱区典型人工林的蒸腾特征及其对气象因子和土壤水分的响应规律,探究其水分利用策略的差异,为该区域的林水综合管理提供理论依据。【方法】2022年5—10月,在六盘山半干旱区叠叠沟小流域选取当地主要的造林树种华北... 【目的】准确量化半干旱区典型人工林的蒸腾特征及其对气象因子和土壤水分的响应规律,探究其水分利用策略的差异,为该区域的林水综合管理提供理论依据。【方法】2022年5—10月,在六盘山半干旱区叠叠沟小流域选取当地主要的造林树种华北落叶松和白桦,各布设1个面积30 m×30 m的固定样地,每个样地选取12株不同胸径的样树,连续测定树干液流密度、气象因子和0~60 cm土层的土壤含水量,分析华北落叶松和白桦人工林蒸腾特征及其对潜在蒸散(PET)和土壤相对可利用水分(REW)的响应差异。【结果】1)7—10月华北落叶松和白桦人工林的日均蒸腾量分别为0.63和0.54 mm·d^(-1),前者比后者高0.09 mm·d^(-1);华北落叶松和白桦林分日蒸腾量随着月份变化均呈先增后减的变化趋势,在7月均达到最大值,分别为1.38和1.45 mm·d^(-1)。2)2种人工林的日蒸腾量对PET的响应均符合指数函数关系,即日蒸腾量随PET增大呈先增大后趋于稳定,但变化趋势在不同REW之间有差别;华北落叶松林分日蒸腾量随PET增长的速率在REW<0.3时较低,在REW>0.3后则迅速升高,且不同REW之间差距很小;而白桦林分日蒸腾量随PET增长的速率持续增大,且比较均匀。3)2种人工林的日蒸腾量对REW的响应也均符合指数函数关系,但变化趋势在不同PET之间有差别;华北落叶松林分蒸腾量随REW增长的速率在PET<2 mm·d^(-1)时较低,在PET>2 mm·d^(-1)后则迅速升高,且不同PET之间差距很小;相比之下,白桦人工林日蒸腾量随REW增大而升高的变化在整个PET变化范围内都比较均匀,且增长速率持续增大。【结论】华北落叶松林分日蒸腾量对PET和REW的响应明显比白桦林更敏感。华北落叶松林分日蒸腾量在PET<2 mm·d^(-1)或REW<0.3时明显高于白桦,但在PET>2 mm·d^(-1)或REW>0.3后迅速升高到其最大值附近并随PET或REW升高保持稳定,而白桦林分日蒸腾量表现为相对均匀地逐渐趋于其最大值。这说明在水分受限的半干旱区,华北落叶松林的蒸腾耗水量高于白桦林,且白桦林蒸腾受干旱期土壤水分的限制更明显。 展开更多
关键词 蒸腾 土壤水分 潜在蒸散 华北落叶松 白桦
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不同品种春小麦生长生理指标及产量对水分响应研究
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作者 王浩莎 曹润宁 黄兴法 《灌溉排水学报》 CAS CSCD 2024年第10期1-10,54,共11页
[目的]系统研究不同程度间歇性干旱对春小麦生长生理及产量的影响。[方法]通过位于甘肃武威的大田试验,以春小麦“陇春41号”和“永良4号”为研究对象,系统研究拔节期和灌浆期不同程度间歇性干旱对春小麦生长生理及产量的影响。在春小... [目的]系统研究不同程度间歇性干旱对春小麦生长生理及产量的影响。[方法]通过位于甘肃武威的大田试验,以春小麦“陇春41号”和“永良4号”为研究对象,系统研究拔节期和灌浆期不同程度间歇性干旱对春小麦生长生理及产量的影响。在春小麦拔节期、灌浆期分别设置灌水量为充分灌溉对照组的65%、80%的亏水处理,即:W1(拔节期65%/灌浆期65%)、W2(拔节期80%/灌浆期65%)、W3(拔节期65%/灌浆期80%)、W4(拔节期80%/灌浆期80%)、W5(充分灌溉对照组)。分析不同处理下春小麦生长指标、产量、叶片光合参数及叶绿素荧光动力学参数对水分的响应规律。[结果]拔节期和灌浆期水分亏缺会对春小麦株高、叶面积指数、干物质积累量、净光合速率、蒸腾速率及光合电子传递速率产生显著负面影响,指标随灌水量减少而降低;抽穗期复水(恢复充分灌溉)后,“陇春41号”LAI得到了明显恢复,复水对春小麦叶绿素量、光合电子传递速率以及蒸腾速率的恢复有显著积极作用;产量随水分亏缺程度的加剧而减小,“陇春41号”整体产量高于“永良4号”,“陇春41号”W4处理下产量与W5处理无显著差异。[结论]考虑节水高产,本文推荐最优灌溉制度为W4处理(拔节期80%/灌浆期80%),推荐种植品种为“陇春41号”。 展开更多
关键词 春小麦 水分亏缺 生长指标 光合特性 光合电子传递速率 叶水势
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基于藻类生长潜力评估调水对藻类生长的影响
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作者 薛立阳 赵恕轲 +2 位作者 胡俊杰 裴国凤 张烨 《生态与农村环境学报》 CAS CSCD 北大核心 2024年第4期513-520,共8页
为评估水体生态健康,量化和确定供水输入的浮游藻类群落对受水水体浮游藻类生长的影响程度具有重要意义。该研究在不同季节的调水期测定了供、受水水体的理化因子,同时利用藻类生长潜力试验比较和分析了不同比例的供、受水水体混合处理... 为评估水体生态健康,量化和确定供水输入的浮游藻类群落对受水水体浮游藻类生长的影响程度具有重要意义。该研究在不同季节的调水期测定了供、受水水体的理化因子,同时利用藻类生长潜力试验比较和分析了不同比例的供、受水水体混合处理后浮游藻类细胞密度和群落结构变化。结果显示,调水期间受水水库的氮磷营养盐浓度没有显著变化(P>0.05)。不同季节的藻类生长潜力试验显示,夏、冬季处理组的浮游藻类细胞密度峰值时间比对照组提前了4 d,且密度峰值随着混合比例的提高而增大;但夏季培养末期(20 d)处理组的浮游藻类密度均低于对照组,同时夏、秋和冬季处理组的实际藻类密度峰值均低于理论估算值,分别低10%、17%~24%和31%。处理组的群落结构变化表现为夏季受水水库的绝对优势种转变为输入的优势种,秋、冬季绝对优势种的相对丰度随调水比例的提高而增加,明显受到供水优势种生长的影响。供、受水水体的营养盐浓度差异是影响藻类生长的主要因素,持续调水显著影响受水水体浮游藻类的群落结构,但在一定程度上降低了发生藻类水华的风险。 展开更多
关键词 调水 理化因子 浮游藻类 群落结构 藻类生长潜力试验
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