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1.
3个树种苗期耐盐性综合评价及指标筛选   总被引:7,自引:0,他引:7  
采用盆栽方法,以卫矛、沙枣和美国白蜡实生苗为材料,用不同浓度的NaCl溶液进行处理,对盐胁迫下各树种的形态表现、生理指标响应和矿质元素的变化进行研究.结果表明:在盐胁迫下植物的相对株高生长量和生物量都受到抑制;叶绿素含量随盐浓度的增加而减少;膜透性、丙二醛(MDA)、超氧化物歧化酶(SOD)、脯氨酸和可溶性糖含量均随盐浓度增加而增加;盐胁迫后,Na+含量在根茎叶中逐渐升高,而K+在不同部位变化规律有所不同,在根中逐渐减少,在茎中无明显的变化;在叶片中,3个树种的变化规律不完全相同.利用相关分析、主成分分析和隶属函数法,对3个树种的耐盐性进行综合评价:卫矛>沙枣>美国白蜡,这与根据盐害症状表现的排序结果相一致.通过灰色关联分析,对14个耐盐评价指标进行筛选,最终筛选出株高相对生长量、膜透性、脯氨酸、根茎叶中的Na+和K+含量是与耐盐性评价有重要相关的指标.  相似文献   

2.
盐胁迫对16种幼苗渗透调节物质的影响   总被引:6,自引:4,他引:2       下载免费PDF全文
采用盆栽的方法,对16种2年生幼苗盐(NaCl)胁迫40 d,并进行耐盐性研究。结果表明:随盐浓度的升高,各树种的脯氨酸、可溶性糖和甜菜碱含量均呈上升趋势,在400 mmol·L-1盐浓度下,沙枣和水蜡的脯氨酸含量比对照分别增加了662.0%和562.8%,而可溶性蛋白含量在各树种间差异较大;Na+和Cl-含量在不同部位(根、茎和叶)均随盐浓度增加而增加,鞑靼忍冬、药鼠李、风箱树和醉鱼草叶片中Na+含量增加了5 20倍。K+和Ca2+含量随树种不同表现各异。综合各树种盐害症状和渗透调节物质变化特性,认为柽柳、唐古特白刺、西伯利亚白刺、卫矛和沙柳具有高度耐盐性,水蜡、沙枣、糖朴、美国皂荚和药鼠李具有中高度耐盐性,杜梨、竹柳、鞑靼忍冬、醉鱼草、风箱树和美国白蜡具有中度耐盐性。脯氨酸、可溶性糖和矿质元素含量(尤其是Na+、K+和Cl-)的变化对植物耐盐能力的影响较普遍也较大。  相似文献   

3.
模拟江苏省沿海地区盐渍土的离子种类及含量,利用土培法对法青Viburnum odoratissimu、海桐Pittosporum tobira和海滨木槿Hibiscus hamabosieb 3种常用绿化灌木进行0.0(CK)、3.0、5.0和8.0 g·kg-1混合盐胁迫处理,研究其叶绿素、Na+、K+及叶片光合系统的响应。结果表明,3种灌木根、茎、叶中Na+含量在受胁迫后都有增长的趋势,且在根中积累的Na+比茎、叶部分更多,其中海滨木槿最为显著。根系对K+的吸收作用在较低盐浓度下(3.0 g·kg-1)即被抑制,而茎、叶对K+的吸收随混合盐浓度的升高也逐步降低。法青、海桐和海滨木槿受盐胁迫后的K+/Na+均为:叶茎根,在相同盐胁迫条件下,海滨木槿、海桐的根、茎、叶均具有更高的K+/Na+比。随着混合盐浓度的升高,3种灌木叶绿素含量、净光合速率、气孔导度及蒸腾速率基本呈下降趋势,法青下降更为明显。结果显示,3种灌木均具有一定的耐盐性,其中海滨木槿耐盐性最强,海桐次之。  相似文献   

4.
以2个耐盐性不同的灌木柳为材料,采用营养液水培,用100 mmol·L-1Na Cl处理幼苗10 d,研究盐胁迫下离子在器官、组织和细胞水平上区域化分布的特性。结果表明:(1)Na Cl胁迫下,灌木柳植株体内K~+含量下降,Na~+和Cl~-含量升高;不同器官间,茎中Na~+和Cl~-含量最高,叶中Na~+和Cl~-含量最低;根向茎运输SK,Na值降低,茎向叶运输SK,Na值提高。(2)与耐盐性较弱的JW2367相比,耐盐性较强的JW2345 SK,Na值变化幅度较大,茎对Na~+的截留作用较强,而叶片中Na~+积累较少,且K~+含量下降幅度较小,说明离子区域化分布的调控能力相对较强,是JW2345耐盐性较强的主要原因之一。(3)对耐盐型JW2345根、茎和叶片横切面进行X射线微区分析表明,盐胁迫下Na~+、K~+和Cl~-在根各组织间均呈均匀分布;在茎中,与对照相比,髓部Na~+、Cl~-升高幅度明显高于周皮和微管组织;叶片栅栏组织中Na~+、Cl~-相对含量增幅最小,且K~+相对含量明显高于表皮和海绵组织。(4)盐胁迫下JW2345茎髓部细胞内离子分布结果显示,液泡对Na~+和Cl~-具有明显的区隔化作用,表明柳树茎髓细胞水平上离子区隔化分布是避免细胞受盐分毒害的重要机制。  相似文献   

5.
盐胁迫对6个树种的生长及生理指标的影响   总被引:19,自引:2,他引:17       下载免费PDF全文
采用水培方式对6个树种盐胁迫后的生长、生理指标进行研究,结果表明:盐胁迫对不同树种苗高净生长量和生物量、根、茎、叶干质量抑制明显,各树种根冠比随胁迫浓度的增加而上升.相对电导率、脯氨酸含量、超氧化物歧化酶活性、可溶性蛋白含量在浓度梯度上差异显著,并随NaCl浓度的增加和处理时间的延长表现出逐渐增加的趋势;在中低盐度胁迫下增加趋势不明显,在高盐度胁迫下迅速上升;各指标在胁迫浓度和胁迫时间上存在交互作用,不同树种对盐胁迫的响应浓度和时间有差异.利用主成分分析法,筛选出苗高增长量、脯氨酸含量、超氧化物歧化酶活性、叶片盐害指数、生物量、相对电导率6个指标作为树种耐盐性评价的指标,采用生长、生理指标与对照的比值,用坐标综合评定法评定的树种耐盐性依次为:旱柳、弗栎>美国皂荚、洋白蜡、蜡杨梅>美国悬铃木.  相似文献   

6.
为了研究彩色树种在NaCl胁迫下矿质离子的响应机制,采用0,85,170,340,510 mmol·L~(-1)五种不同浓度NaCl溶液对金叶复叶槭Acer negundo 'Aurea',紫叶合欢Albizia spp.和金叶皂荚Gleditsia triacaanthos 'Sunburst'2年生苗进行胁迫处理,50天后,根据其表型评判各树种盐害等级,并测定其根、茎和叶中Na~+,K~+,Ca~(2+)含量,计算各组织的K~+/Na~+和Ca~(2+)/Na+值。结果表明,在340 mmol·L~(-1) NaCl浓度下,金叶复叶槭绝大部分叶片边缘焦枯,盐害等级为3,紫叶合欢和金叶皂荚部分叶片焦枯,盐害等级为2,而510 mmol·L~(-1)NaCl浓度下,紫叶合欢盐害等级为4级,而金叶皂荚的盐害等级为3级;3个树种根、茎和叶中Na~+含量均随着盐浓度增加而增加,而K~+含量和K~+/Na~+均显著下降(P0.05),并且金叶皂荚降幅少于金叶复叶槭和紫叶合欢;Ca~(2+)含量均随着盐浓度增加呈下降趋势,根和叶的Ca~(2+)/Na~+在金叶皂荚中的降幅小于金叶复叶槭和紫叶合欢。因此,在NaCl胁迫下,金叶皂荚盐害等级低,归因于其具有较强的拒Na~+和保留K~+,Ca~(2+)能力,从而维持体内K~+/Na~+,Ca~(2+)/Na+平衡。  相似文献   

7.
采用不同浓度NaCl溶液盆栽浇盐的方法对3个树种盐胁迫后的生长、生理指标进行研究,结果表明:盐胁迫下不同树种相对生长量和生物量随盐浓度的增加而下降。各指标在胁迫浓度下存在交互作用,不同树种对盐胁迫的响应浓度有差异。利用相关性分析法,分析出各生理指标之间的相关性,采用综合法评定树种耐盐性依次为:梭梭(Haloxylon ammodendron)枸杞(Lycium barbarumL.)白榆(Ulmus pumila)。  相似文献   

8.
为在河西走廊园林绿化中更加科学地选择树种,以蓝叶忍冬、连翘、贴梗海棠、红刺玫、紫叶小檗和紫丁香为试验材料,采用盆栽控制土壤水分,测定不同水分条件下6个树种的盐害指数、叶绿素含量、膜透性等生理生化指标,并通过隶属函数法对6个树种的耐盐性进行综合评价。结果表明,随着盐胁迫浓度增大,各树种均表现为盐害指数增大,SOD、POD含量下降,叶绿素含量减少,MDA含量和膜透性增加,且各指标存在树种差异。通过对各个指标进行综合评价得出,盐胁迫处理下6个树种的耐盐性排序为红刺玫>紫丁香>连翘>紫叶小檗>贴梗海棠>蓝叶忍冬。  相似文献   

9.
以江西萍乡、山东平度、江苏盐城3个种源地的海州常山组织培养苗为材料,采用不同浓度NaCl进行胁迫处理,分析其对海州常山生长、离子选择吸收和运输的影响,探讨不同种源海州常山的耐盐差异和耐盐机理。结果表明:(1)NaCl胁迫下,海州常山生物量下降,含水量降低,生长受到抑制;(2)随着NaCl浓度上升,Na~+的吸收为先升后降,高浓度NaCl胁迫下,江西萍乡种源Na~+主要集中在叶柄中,而山东平度种源Na~+主要集中在茎部;K~+含量随着NaCl胁迫的增加呈下降的趋势,在叶片中含量较高;K~+/Na~+随NaCl浓度的增加呈下降趋势;(3)随着NaCl浓度增加,根系选择吸收系数SAK,Na、离子运输系数STK,Na先增后降(山东平度茎秆运输除外),总体而言,盐城种源SAK,Na,STK,Na的值大于其他种源,根抑制Na~+、促进K~+向地上部运输的能力也较其他种源强。综合分析表明:高浓度的盐胁迫对不同种源均产生不利影响,造成植物体内盐离子积累,但盐城种源保持体内离子平衡能力和耐盐性高于其他种源。  相似文献   

10.
喜树种源耐盐能力评价及耐盐指标筛选   总被引:2,自引:0,他引:2  
以云南昆明(KM)、湖南邵阳(SY)、湖南浏阳(LY)、浙江龙泉(LQ)、浙江长兴(CX)、江苏南京(NJ)、贵州贵阳(GY)、江西南昌(NC)、广西桂林(GL)、安徽黄山(HS)10个种源的1年生喜树苗木为试验材料,设置3个盐含量梯度,即NaCl占土壤干质量的0,0.2%,0.6%,研究不同NaCl处理对喜树苗木生长及生理生化指标的影响。结果表明:1)随着NaCl胁迫程度增加,10个喜树种源苗高、地径和生物量均呈下降趋势,而根冠比呈上升趋势,LQ和CX种源的生长受到抑制最为明显。2)NaCl胁迫下喜树苗木的SOD活性,丙二醛、可溶性糖、可溶性蛋白、Na+含量和Na+/K+值上升,叶片相对含水量下降,K+含量和POD活性先上升后下降。3)根据0.6%浓度NaCl胁迫下各种源苗木总生物量大小,10个喜树种源的耐盐能力从大到小依次为LY>NC>GL>HS>SY>GY>KM>NJ>LQ>CX。4)逐步回归分析表明:喜树叶片中可溶性糖含量、MDA含量、Na+/K+比对总生物量有极显著的影响,因此可以用可溶性糖含量、MDA含量、Na+/K+比等作为评价喜树耐盐能力的参考指标。  相似文献   

11.
Unproductive saline and waterlogged (WT) wastelands could be beneficially transformed into agroforestry systems using trees tolerant to these stresses. We studied the salinity and waterlogging tolerance of five Australian tree species (Acacia salicina, Casuarina glauca, Casuarina obesa, Eucalyptus camaldulensis and Eucalyptus occidentalis) during seedling stage and their relationships with root and leaf ion concentrations. 8-month old plants were exposed for 5 months to five irrigation water salinity treatments (EC values between 2 and 22 dS m?1) and two waterlogging treatments (drained or WT). The salinity tolerance of the five species was high, although decreased in WT conditions. Irrespective of salinity, the two Casuarina species were more tolerant and the other three species were less tolerant to WT than drained conditions. In all species, salinity and waterlogging increased leaf Cl? and Na+ and decreased leaf Ca2+, but not leaf K+. Root Cl? and Na+ increased with salinity but not with waterlogging. Salinity tolerance was negatively correlated with Cl? and Na+ leaf accumulation rates per unit increase in salinity. Waterlogging reduced the ability of the seedlings to exclude Cl? and Na+ from the leaves. The two most salt tolerant Casuarina species under both drained and WT conditions showed the highest leaf Cl? and Na+ exclusion and the highest root Cl? and Na+ accumulation, suggesting that sequestration of these toxic ions in their roots was a significant salt-tolerant mechanism. Revegetation of saline and WT wastelands with these tolerant Casuarina species could be profitably used for biomass, biofuel and renewable energy production.  相似文献   

12.
We studied ion distribution in roots and the growth of Cyclocarya paliurus seedlings of three provenances, Huangshan in Anhui, Jiujiang in Jiangxi and Kunming in Yunnan, under conditions of 0, 1, 3 and 5 g/L NaCl stress using X-ray microanalysis. Results show that under NaCl stress of 3 and 5 g/L, the relative contents of Na+ and Cl in root tissues increased, while the relative contents of K+, Ca2+ and Mg2+ decreased. With an increase in salinity, the relative content of Na+ in the epidermis and cortex of the root increased, while the relative content of Cl in the stele and cortex of the root increased markedly. Thus, ions in the root tissues were unbalanced and the ratios K+/Na+ and Ca2+/Na+ decreased, while Na+/(K++ Na++Ca2++Mg2+) increased. The decrease of the K+/Na+ ratio and the substantial increase of Cl in root tissues contributed to a decline in seedlings survival and reduced the increments for seedling leaf area, height, basal diameter as well biomass. Our preliminary conclusion is that the level of salt tolerance for the tested provenance seedlings was in the order of Huangshan > Kunming > Jiujiang, and the threshold of salt tolerance for C. paliurus seedlings was about 1 g/L. __________ Translated from Scientia Silvae Sinica, 2008, 44(6): 66–72 [틫自: 쇖튵뿆톧]  相似文献   

13.
The effect of NaCl on growth, biomass and ion relations of two salt-tolerant isolates of Paxillus involutus, MAJ and NAU were investigated. The two Paxillus strains were exposed to the following concentrations of NaCl: 0, 100, 200 and 500 mmol·L^-1. Growth of MAJ and NAU was enhanced by 100 mmol·L^-1 NaCl but severely inhibited at the concentration of 500 mmol·L^-1. NAU exhibited a greater capacity to exclude Na^+ and Cl^- under all salinity levels, whereas the salt-includer MAJ had a higher capacity in nutrient uptake under salt stress. The ratios Na^+/K^+, Na^+/Ca^2+ and Na^+/Mg^2+ in NaCl-treated MAJ and NAU did not increase at levels of 100 and 200 mmol·L^-1 NaCl but markedly increased at 500 mmol·L^-1. This suggests that the two strains, especially MAJ, enhanced nutrient uptake corresponding to the increased Na^+ influx at moderate salinity. We conclude that both MAJ and NAU are able to tolerate 500 mmol·L^-1 NaCl but there are species-specific differences in retaining ionic homeostasis in the two Paxillus strains. NAU is a salt-excluder, MAJ is a salt-includer but retains a high capacity in nutrient selectivity under saline conditions. Their definite mechanisms to enhance salt tolerance of mycorrhizal hosts need further study.  相似文献   

14.
In order to explore the salt tolerance mechanism of Machilus thunbergii, the effects of salt stress on seedling biomass, root morphology, sodium and potassium absorption and distribution were studied. The results showed that the above-ground biomass increased slightly under lower salt stress conditions, while the below-ground biomass, root length and root surface area showed a downtrend. The above-ground growth was limited under high concentration salt stress, while the under-ground growth was not subject to significant restrictions. The absorption of Na+ in root increased under salt stress, but that of K+ decreased. The ability of Na+ transporting from root to leaf and stem was weakened. The accumulation of Na+ in stem and leaves was less. With the decreased absorption of K+, the ratio of Na+/K+ also continuously increased. With the increased concentration of salt stress, the ability of K+ absorption in roots increased. The ability of K+ transporting from root to leaf and stem was enhanced, which resulted in significant increase of K+ in the leaves and stem. The accumulation of Na+ in the under-ground was significantly greater than that in above-ground, while the K+ content in above-ground increased significantly, which played a key role in maintaining normal growth and metabolism of M. thunbergii.  相似文献   

15.
To evaluate genotypic difference in antioxidative ability and salt tolerance in poplars, the authors investigated the effects of increasing content of soil NaCl on salt concentration in leaves, superoxide dismutase (SOD) and peroxidase (POD) activities, malondialdehyde (MDA) content, and membrane permeability (MP) in Populus euphratica Oliv., P. popularis “35–44,” and P. × euramericana cv. I-214 (hereafter abbreviated as P. cv. I-214). Na+ and Cl concentrations in leaves of P. popularis increased markedly over the increase of the duration of exposure to salinity, and culminated after 28 days of salt stress. SOD and POD activities declined correspondingly, followed by significant increases of MDA and MP, and leaf injury was finally observed. Compared with P. popularis, leaf Na+ and Cl in P. cv. I-214 exhibited a trend similar to P. popularis, but a lower salt-induced increase of MDA and permeability was observed and lighter leaf necrosis occurred. In contrast to P. popularis and P. cv. I-214, SOD and POD activities in P. euphratica leaves increased rapidly at the beginning of salt stress with a light soil NaCl concentration of 58.5 mmol/L. Furthermore, salt ion concentration, MDA content, and MP in P. euphratica leaves did not increase significantly during 28 days of increasing salt stress. Therefore, the increase in MP in P. popularis and P. cv. I-214 had a close relationship with a salt buildup in leaves under increasing salt stress. Salt-induced declines of SOD and POD activities might accelerate lipid peroxide and consequently resulted in ion leakage. P. euphratica rapidly activated antioxidant enzymes after the onset of salt stress, which might reduce the accumulation of reactive oxygen species and the subsequent acceleration of lipid peroxide. P. euphratica leaves exhibited a higher capacity to exclude salt in a longer period of increasing salinity, thus limited salt-induced lipid peroxide and MP, which contributed to membrane integrity maintenance and salt tolerance of P. euphratica. Translated from Journal of Beijing Forestry University, 2005, 27(3) (in Chinese)  相似文献   

16.
We assessed the effect of seasons and the tree species velvet maple (Acer velutinum Boiss), Hainbuche hornbeam (Carpinus betulus L.) and chestnut-leaved oak (Quercus castanefolia C. A. Mey.; Fagaceae) on nutrient fluxes (Na+, K+ and Ca2+) in throughfall (TF) and litter flow (LF) from January 2012 to February 2013. Potassium (K+) and calcium (Ca2+) in total TF and LF over the measurement period significantly differed between 3 the species (p < 0.05). Maple and oak trees had significantly higher fluxes of K+ and Ca2+ in their TF, respectively. The average quantity of nutrients in LF was significantly higher in the leafy season than in the leafless season for all cations except for Na+. Under velvet maple trees, the average flux of nutrients (Na+, K+, and Ca2+) in TF was significantly higher than LF. Lastly, leaching of potassium (K+) and calcium (Ca2+) in LF during the measurement period was significantly lower than TF under the hornbeam trees. Our results suggest that different tree species may impact the nutrient availability and possibly the sustainability of Hyrcanian forests. Further research is needed to determine how managing different species will affect the long-term nutrient status of these forests.  相似文献   

17.
NaCl胁迫下沙枣幼苗的离子代谢特性   总被引:2,自引:1,他引:2       下载免费PDF全文
[Objective]To further understand the ion metabolism characteristics of Elaeagnus angustifolia L. under NaCl stress.[Method]The seedlings of two E. angustifolia L. provenances, which were Alaer (salt tolerance provenance) and Yinchuan (salt sensitive provenance), were treated by three NaCl concentrations (0,150,300 mmol·L-1) and sampled at the 7th day and the 30th day to measure the Na+ , K+, Ca2+, and Mg2+ contents, K+/Na+ ratio and selective absorption and transportation of K+ in tissues (roots, stems and leaves). [Result]The results showed that the Na+ content in the organizations of E. angustifolia L. sharply increased with the increase of NaCl concentration. With prolonging of stress time, the Na+ content increased in roots, and decreased in stems and leaves. After seedlings of the two provenances were treated with 150 mmol·L-1 NaCl for 7 days, the Na+ content was 2.10 times and 2.23 times in leaves, respectively, compared with the control groups, and was 1.79 times and 1.57 times in root. Meanwhile, the difference between two provenances showed a expanding trend with the increase of NaCl concentration and stress time. With the increase of NaCl concentration and extension of stress time, the K+ content, Ca2+ content and K+/Na+ ratio in organizations decreased gradually. Meanwhile, the Alaer provenance seedlings accumulated more Na+ in roots and less Na+ in leaves than that of Yinchuan provenance, and the K+ content, Ca2+ content and K+/Na+ ratio decreased less in the Alaer provenance seedlings than those of Yinchuan provenance. With the increase of NaCl concentration, the Mg2+ content in leaf gradually decrease, but the Mg2+ content in root increased 22.8~64.4% after salt stress for 7 days, and Alaer provenance seedlings increased more than Yinchuan provenance. After 30 days, there was non-significant difference with the control group on the Mg2+ content of root. K+ selective absorption of E. angustifolia L. seedlings significantly increased with increasing salt concentration of the media at the 7th days, whereas not obvious at the 30th days. When the concentration of NaCl in the media increased, the change of K+ selective transportation was not significant. [Conclusion]E. angustifolia L. seedlings increase Mg2+ content and K+ selective absorption in the roots at the early stage of salt stress to adapt saline environment. The salt-tolerance E. angustifolia L. provenance can cut off more Na+ in roots and reduce Na+ content in leaves, which cause less K+, Ca2+ and Mg2+ contents loss, especially the roots and leaves, so as to ensure that all kinds of metabolisms can go well.  相似文献   

18.
3种白刺耐盐性的对比分析   总被引:7,自引:5,他引:2       下载免费PDF全文
以2年生西伯利亚白刺、齿叶白刺和唐古特白刺苗为材料,设置0、100、200、300、400 mmol.L-1NaCl 5种盐浓度开展胁迫试验,测定并对比分析其对盐胁迫的生长及生理生化响应。结果表明:低盐浓度处理促使白刺生长速度和生物量增加、叶绿素含量增高,高盐浓度处理下这种促进作用降低;在100 mmol.L-1的盐处理下,唐古特白刺、西伯利亚白刺、齿叶白刺叶绿素含量均达最高,分别为0.72、0.78、0.61 mg.g-1;在400 mmol.L-1的盐处理下,唐古特白刺、西伯利亚白刺、齿叶白刺生物量为最低,分别为10.49、12.42、10.19 g.株-1,仅为对照的75%79%;3种白刺中,唐古特白刺的Na+/K+最高,施盐处理下西伯利亚白刺的Na+/K+均高于对照,而齿叶白刺则低于对照;随着盐浓度的增加,3种白刺叶片中可溶性蛋白的含量递增,可溶性糖含量则先增后减;低盐浓度处理的唐古特和西伯利亚白刺叶片中MDA含量比对照低,齿叶白刺却比对照高;3种白刺的POD和SOD活性在盐处理下高于对照,其中唐古特白刺叶片中POD活性最低,齿叶白刺中SOD活性最高;3种白刺在盐胁迫下均能正常生长。  相似文献   

19.
This paper evaluates the potential of nine multipurpose tree species for afforestation of degraded land in the Khorezm region, Central Asia, particularly their suitability for biodrainage i.e., lowering the elevated groundwater table through the transpirative capacity of plantations. For this purpose water use (WU), water use efficiency (WUE) and tree physiological factors influencing transpiration were assessed during two consecutive years. Mean daily leaf transpiration differed significantly among the species and ranged during the seasons from 4.5–5.2 mmol m−2 s−1 for Prunus armeniaca L. to 4.5–10 mmol −2 s−1 for Elaeagnus angustifolia L. WU differences were triggered by species physiological features such as capability of water uptake by roots. Transpiration rates and the length of fine roots correlated highly (r = 0.7). Correlations of leaf transpiration rates with leaf area were weaker (r = 0.6). No correlations were found between salt content in plants and water uptake under conditions of slight-to-moderate rootzone soil salinity. Values of WUE per root and shoot DM were similar averaging, respectively, 0.2 and 0.3 g DM g−1 water for two-year-old trees, and decreased with age. In addition to WU characteristics, also salinity tolerance, growth rate and the ability to produce fodder and fuelwood must be considered during species selection. Regarding these features, the N-fixing E. angustifolia ranked the highest, combining high WU, fast growth and production of nutritious feed. Examined Populus spp. and Ulmus pumila L. ranked lower but still represented potential candidates for biodrainage purposes. Typical fruit species in the region such as P. armeniaca and Morus alba, showed low biodrainage potential.  相似文献   

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