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1.
红豆草与土壤氮含量对大气二氧化碳浓度升高的响应   总被引:1,自引:0,他引:1  
在封闭的植物培养箱中,通过盆栽实验,研究了红豆草和土壤氮含量对CO2浓度增加的响应.结果表明,与正常CO2浓度(355~370 μmol·mol-1)相比,CO2浓度升高(700 μmol·mol-1),植物生物量增加25.1%(P<0.01),但植物体氮浓度降低25.3%(P<0.001),植物全氮没有显著的变化.经3个月盆栽实验后,与原始土壤相比,两种CO2浓度处理土壤全N、NO3--N和NH4+-N都有所降低,而土壤微生物氮则显著增加,这可能与植物生长有关.不同CO2浓度处理土壤NH4+-N浓度基本一致,但在高CO2浓度下,土壤NO3--N浓度显著降低,而微生物生物氮显著增加.对整个土壤-植物系统而言,盆栽实验后,整个系统全氮有少量增加,但变化不显著,特别是在高CO2浓度条件下,土壤-植物系统全氮最大,这可能与培养材料红豆草为豆科植物,而且在高CO2浓度下生物量增加,导致氮的固定量增加有关.  相似文献   

2.
二氧化碳浓度升高对太湖沉水植物马来眼子菜生长的影响   总被引:1,自引:0,他引:1  
通过室外培养试验,研究不同CO2浓度条件下沉水植物马来眼子菜的生长及生理变化.结果表明:CO2浓度升高(1000 μmol·mol-1)条件下,马来眼子菜单株的平均生物量增加了44.3%(P<0.01),茎生物量比重下降了5.5%(P<0.05);根和叶中氮含量分别下降了18.1%和6.4%(P<0.05),而茎中氮含量变化不明显(P>0.05);根、茎、叶中磷含量分别增加了22.2%(P<0.05)、26.6%(P>0.05)和38.8%(P<0.05);可溶性糖含量增加了27.3%、18.3%和37.5%(P<0.05);根、茎和叶中全碳含量增加了4.6%、5.3%和2.0%;CO2浓度升高使水体中氮、磷含量分别下降了7.9%和5.1%(P<0.05),但对底泥中氮、磷的含量影响不明显.CO2浓度升高将对沉水植物生长及其生境有一定影响.  相似文献   

3.
水肥处理对黄瓜土壤养分、酶及微生物多样性的影响   总被引:6,自引:0,他引:6  
以津优1号黄瓜为试材,设3个土壤相对含水量水平(50%~60%、70%~80%、90%~100%)和2个肥料追施量(600 kg N·hm-2和420 kg P2O5·hm-2,420 kg N·hm-2和294 kg P2O5·hm-2)处理,研究了不同水肥供应对日光温室黄瓜土壤养分、酶活性及微生物多样性的影响.结果表明:土壤中NH4+-N含量随施肥量的增加而提高,随土壤相对含水量的增加而降低;水肥供给的增加有利于提高土壤中速效磷含量和蔗糖酶活性;肥料增加使土壤中蛋白酶活性降低,而水分降低使土壤中脲酶活性提高.土壤中微生物多样性与土壤中养分含量无显著相关性,与土壤脲酶活性呈显著正相关,与蔗糖酶活性呈显著负相关.土壤相对含水量70%~80%、氮肥追施量600 kg N·hm-2和420 kg P2O5·hm-2处理的土壤养分含量、蔗糖酶、磷酸酶和脲酶活性较高,且土壤中微生物多样性和均匀度显著高于其他处理,土壤生产潜力最优.  相似文献   

4.
猪粪中铜对东北黑土的污染风险评价   总被引:8,自引:0,他引:8  
集约化养殖使用大量铜(Cu)作为饲料添加剂,养殖废物的排放和利用可导致一定的环境问题.本文以东北黑土为供试材料,通过在盆栽试验中添加不同Cu浓度的猪粪来模拟不同施肥年限的菜园土,研究土壤中Cu累积对小白菜地上部分Cu浓度、地上部分生物量、土壤微生物生物量碳和土壤酶(脱氢酶、脲酶、酸性磷酸酶)活性的影响.结果表明:单独施用猪粪显著增加了小白菜地上部分生物量,对其Cu浓度则没有显著影响.猪粪的施用在一定时期内显著促进了脱氢酶和脲酶的活性,但随土壤Cu浓度的增加,脱氢酶、脲酶、酸性磷酸酶活性逐渐受到抑制.当土壤全Cu浓度达到301.3 mg·kg-1后,小白菜地上部分生物量、土壤微生物生物量碳及脱氢酶、脲酶、酸性磷酸酶活性均受到强烈抑制.小白菜地上部分Cu浓度与土壤全Cu和水溶态Cu浓度呈显著正相关(P<0.01),而地上部分生物量与土壤全Cu浓度呈显著负相关(P<0.05).研究表明,可用于种植蔬菜的黑土Cu浓度阈值应小于301.3 mg·kg-1.  相似文献   

5.
铜对节节草生理代谢及抗氧化酶活性的影响   总被引:10,自引:1,他引:9  
采用盆栽试验方法,研究了重金属Cu对节节草的生理代谢及抗氧化酶活性的影响.结果表明,低浓度Cu(500 mg·kg-1)处理下节节草生理代谢变化不明显.高浓度Cu(1 000~3 000 mg·kg-1)处理下,节节草体内叶绿素a和叶绿素b含量均显著下降,叶绿素b的含量仅为对照的43%;可溶性糖含量平均为对照的1/2,细胞膜透性平均高出对照1~2倍,MDA含量平均为对照的1~3倍,表明高浓度Cu胁迫对节节草细胞质膜系统及主要细胞器的结构与功能具有破坏作用.Cu胁迫下节节草抗氧化酶活性随Cu浓度增加而上升,POD和SOD酶活性平均分别增长34.73%和51.55%,且与Cu浓度呈显著正相关(rPOD=0.978,rSOD=0.926,P<0.05).  相似文献   

6.
绿斑病藻寄生对夏橙叶片光合作用特性的影响   总被引:1,自引:0,他引:1  
以盆栽的2年生奥灵达夏橙为试材,研究了绿斑病藻寄生对夏橙叶片光合作用特性的影响.结果表明,轻度病叶对叶绿素总量(Chl a+b)、类胡萝卜素含量(Car)、净光合速率(Pn)、胞间CO2浓度(Ci)、原初光能转换效率(Fv/Fm)、光合电子传递量子效率(ΦPS Ⅱ)和光化学猝灭系数(qP)无显著影响;中度病叶和重度病叶的Chla+b、Car、Pn、Fv/Fm、ΦPS Ⅱ和qP较对照分别下降了23.85%、26.49%、43.3%、4.5%、35.1%、22.5%和37.61%、44.04%、64.5%、8.6%、63.6%、40.1%,与对照差异显著,而Ci较对照显著上升.绿斑病藻的大量寄生减弱了夏橙叶片的光合作用,而净光合速率的下降主要是由非气孔因素限制引起.  相似文献   

7.
大气CO2浓度升高对不同施氮土壤酶活性的影响   总被引:4,自引:1,他引:3  
利用中国唯一的无锡FACE(Free-air CO2 enrichment,开放式空气CO2浓度升高)平台,研究了大气CO2浓度升高对土壤β-葡糖苷酶、转化酶、脲酶、酸性磷酸酶、β-氨基葡糖苷酶的影响。研究发现,不同氮肥处理下大气CO2浓度升高对某些土壤酶活性的影响不同。在低氮施肥处理中,大气CO2浓度升高显著降低β-葡糖苷酶活性,但是在高氮施肥处理下,大气CO2浓度升高显著增加β-葡糖苷酶活性。在低氮和常氮施肥处理中大气CO2浓度升高显著增加了土壤脲酶活性,但在高氮水平下影响不显著。在低氮、常氮施肥处理中,大气CO2浓度升高对土壤酸性磷酸酶活性没有影响,而在高氮施肥处理中显著增强了土壤中磷酸酶活性。大气CO2浓度升高对土壤转化酶活性和β-氨基葡糖苷酶的活性有增加趋势,但影响不显著。研究还发现,在不同的CO2浓度下,土壤酶活性对不同氮肥处理的响应也不同。在正常CO2浓度下,土壤中β-葡糖苷酶活性随着氮肥施用量的增加而降低,而在大气CO2浓度升高条件下,却随着氮肥施用量的增加而增加。在大气CO2浓度升高条件下,高氮施肥显著增加了转化酶和酸性磷酸酶活性,而在正常CO2浓度下,影响不显著。在大气CO2浓度升高条件下,氮肥处理对脲酶活性的影响不大,但在正常CO2浓度下,脲酶活性随着氮肥施用量的增加而增加。氮肥对β-氨基葡糖苷酶活性的影响不明显。  相似文献   

8.
以盆栽枳椇和皂荚为试材,研究了不同浓度NaCl处理(CK、0.15%、0.30%、0.45%、0.60%)对枳椇和皂荚植株生长、叶绿素荧光特性和活性氧代谢的影响.结果表明:随着NaCl浓度的提高,植株生长量、叶片叶绿素含量、Fv/Fm、ΦPSⅡ、qP均逐渐下降,而qN逐渐升高.0.15% NaCl胁迫10 d后,枳椇叶片叶绿素含量、Fv/Fm、ΦPSⅡ、qP较对照处理分别降低了19.77%、2.94%、29.03%、8.16%,差异显著(P<0.05),而皂荚与对照处理差异不显著;0.30%NaCl胁迫下,皂荚Fv/Fm和ΦPSⅡ较对照处理分别降低了1.91%、14.66%,差异显著(P<0.05);0.45%NaCl胁迫下,皂荚叶片叶绿素含量和qP与对照处理差异显著(P<0.05),分别降低了29.28%和11.36%.随着NaCl浓度的增加,皂荚SOD活性持续升高,枳椇呈先升高后降低变化,在0.15% NaCl胁迫下达最大值;两种苗木细胞POD、CAT活性均呈先升后降趋势,且皂荚的升幅大于枳椇.二者的MDA含量均呈上升趋势,且枳椇的升高幅度大于皂荚,说明枳椇产生了较严重的膜脂过氧化.由此推断,皂荚的耐盐性较强与其具有较强的抗氧化保护酶系统有关.  相似文献   

9.
高浓度二氧化碳处理后凤梨光合作用的恢复   总被引:2,自引:0,他引:2  
对紫星凤梨和丹尼斯凤梨在高CO2浓度[T1(600±40) μmol·mol-1, T2(900±40) μmol·mol-1]下处理150 d后转移到大气环境中30 d内的光合作用、光合关键酶活性等的恢复情况进行了研究. 在大气环境中紫星凤梨T1、T2处理的净光合速率分别比对照低7.41%和13.33%,丹尼斯凤梨T1处理净光合速率接近于对照, 而T2处理略高于对照;两种凤梨T1、T2处理叶片中淀粉与可溶性糖的积累在恢复30 d时接近对照组的水平,Rubisco与乙醇酸氧化酶活性与对照的差别减小,但仍低于对照.  相似文献   

10.
硅对生姜叶片水、二氧化碳交换特性的影响   总被引:5,自引:0,他引:5  
为探讨硅对生姜植株的生理效应,以莱芜大姜为试材,研究了水培营养液中不同硅素水平对生姜植株生长、硅含量及叶片光合作用和蒸腾作用的影响.结果表明:植株各器官硅含量及生物量均随营养液硅素水平的升高而显著增加,1.0 (T1)、1.5 (T2)、2.0 (T3) mmol·L-1硅(Si)处理植株叶片硅 (SiO2) 含量分别比CK增加604.4%、834.8%和1130.4%,单株生物量分别比CK增加9.4%、19.4%和22.8%.随着硅素水平的升高,叶片Mg2+ TPase、Ca2+ ATPase活性及光合速率(Pn)和水分利用效率(WUE)提高,蒸腾速率(Tr)降低.一天中在11:00时,T1、T2、T3处理的生姜叶片Pn和WUE分别比CK提高11.2%、21.8%、28.2%和23.1%、55.9%、54.8%,Tr分别比CK降低6.3%、17.1%和19.2%.此外,硅素还显著提高了生姜叶片光合作用饱和光强、CO2羧化效率及类胡萝卜素含量,但对叶绿素含量无显著影响.本试验条件下,以15~20 mmol·L-1硅素(Si)处理效果最好.  相似文献   

11.
Axillary bud cultures of six low-land tropical varieties of potato Solanum tuberosum (L. T. 2, 5, 6, 7, 8 and 9) were studied for their response to salinity stress using crude sea salt. Concentrations of 0.8% and above severely inhibited the growth, while decreased growth was observed between 0.4% and 0.6% salt in all the varieties, with occasional shoot tip necrosis and compound leaf formation. A lower concentration of salt (0.2%) was beneficial and increased shoot weight in most varieties. Protein content showed a positive correlation with proline levels, indicating that proline accumulation was due to new synthesis rather than breakdown of existing proteins. Soluble carbohydrates increased in the stem with increasing salt. Roots showed an increase in sodium content while shoots showed increased potassium levels, with increasing salt concentrations. There was a positive correlation between dry weight yields and K/Na ratio. It is apparent that the synthesis of proline, accumulation of soluble carbohydrates as well as increase in potassium and sodium content were all used to adjust the physiology in response to salt stress by the different varieties of potato, with varying degrees, in the present study.  相似文献   

12.
不同盐分水平对柽柳扦插苗根系生长及生理特性的影响   总被引:4,自引:0,他引:4  
柽柳(Tamarix chinensis)作为黄河三角洲湿地的优势种之一,对盐渍化环境具有较好的适应性。根系作为植物直接感受盐分变化的器官,其对盐分条件的响应特征对研究植物生存、湿地恢复、土壤改良等具有重要意义。以一年生柽柳插穗为研究材料,采用水培法,设置6个盐分水平:CK(空白对照)、0.4%、0.8%、1.2%、2.4%、3.6%进行试验,测定柽柳生根率、根寿命、根系生物量等生长指标及根中ATP合成酶和过氧化氢酶(CAT)活性及脱落酸(ABA)含量,研究柽柳根系生长及生理特性对不同盐分水平的响应。结果表明:(1)柽柳适合扦插繁殖的培养溶液含盐量低于0.8%;含盐量超过0.8%后,扦插生根率显著降低,根系寿命减短。(2)柽柳根长生长随含盐量升高呈下降趋势;主根数随含盐量升高先增加,至含盐量超过1.2%后逐渐减少。(3)柽柳可通过调整生物量的分配模式来适应盐环境,低盐时地上部生物量高于地下,高盐时根系生物量比例逐渐增加,但生物量仍低于地上部分。(4)ATP合成酶活性、CAT活性在含盐量低于0.8%时增加;含盐量超过0.8%时,活性降低;脱落酸(ABA)含量随含盐量增加先增加,含盐量超过1.2%时减少。  相似文献   

13.
通过防雨棚小区栽培,控制土壤供水系数(Kw)分别为0.8、0.6、0.4、0.2,以自然状况下的小区为对照(CK),研究土壤水分条件对冬小麦生育后期叶片气体交换及叶绿素荧光参数的影响。结果表明:Kw为0.6处理的冬小麦叶片叶绿素含量与0.8处理接近,且显著高于其他处理(P<0.05);Kw为0.6处理对冬小麦叶片的气孔导度和蒸腾速率有轻度抑制,但其光合速率却高于0.8处理,而Kw为0.2处理的光合速率、气孔导度及蒸腾速率均为最低;气孔限制值在Kw为0.4处理下最高,其次为0.2处理,0.8处理下最低;冬小麦叶片的表观量子效率在Kw为0.4处理下最高,光补偿点总体上随着土壤水分含量的降低呈下降趋势,而光饱和点及最大光合速率则以Kw为0.6处理最高,其次为0.8处理,0.2处理最低;冬小麦叶片的天线转化效率Fv’/Fm’、电子传递速率ETR、实际量子效率ФPSII及光化学猝灭qP均以Kw为0.6处理最高,其次为0.8处理,0.2处理下最低;在Kw为0.2处理下,冬小麦光合作用主要受非气孔因素限制,而在0.4处理下,则主要受气孔因素限制。  相似文献   

14.
The growth and nodulation ofTrifolium alexandrinum were compared at six levels (0 - 1.2 % NaCl) of salinity. Dry mass of shoots and roots, 14 and 20 weeks after the commencement of salinity treatment, increased at low levels of salinity (0.1 - 0.2 % NaCl) but decreased with higher NaCl concentrations (0.4 - 1.2 %). Nodulation occurred at NaCl concentrations up to 0.8 %. Nodule mass decreased with increasing salinity levels. The nodule size remained unaffected at NaCl concentrations up to 0.4 % but was reduced at higher concentrations.  相似文献   

15.
不同能源柳无性系对NaCl胁迫的生理响应   总被引:3,自引:0,他引:3  
刘斌  张文辉  马闯  刘新成 《生态学报》2010,30(4):895-904
为了探索不同能源柳无性系的耐盐潜力,在盆栽条件下,对1年生能源柳无性系2、4、C、E扦插苗设置NaCl盐分梯度,使其土壤含盐量保持在0、0.2%、0.4%、0.6%、0.8%,并以乡土旱柳为对照,胁迫45d后,对5个无性系的气体交换参数、保护酶活性和有机渗透调节物质进行测定。研究发现:(1)在低浓度盐胁迫下(土壤含盐量0 0.4%),导致各能源柳光合速率降低的是气孔因素;在高浓度盐胁迫下(土壤含盐量大于0.4%),导致各能源柳无性系光合速率下降的主要是非气孔因素。(2)随着土壤盐浓度的增加,各能源柳无性系的过氧化氢酶(CAT)活性逐渐减小,过氧化物酶(POD)活性先增加后减小,而超氧化物歧化酶(SOD)活性呈现增加的趋势,并且4个能源柳无性系在盐胁迫条件下保护酶活性强于旱柳。(3)在土壤含盐量小于0.6%时,4个能源柳无性系的可溶性蛋白含量始终大于旱柳;在整个胁迫过程中,能源柳C的脯氨酸含量始终大于旱柳。(4)与旱柳相比,4个能源柳无性系在土壤含盐量0 0.4%的土壤中都能良好生长,其中能源柳C的耐盐潜力更大,可在土壤含盐量为0.6%的土壤中正常生长。这说明,4个能源柳无性系均可在天津轻、中度盐渍化地区栽培。  相似文献   

16.
Experiments were carried out to investigate the nematicidal potential of a cyanobacterium, Oscillatoria chlorina, against the root-knot nematode, Meloidogyne arenaria on tomato plants grown in pots filled with 500 cm3 of field soil infested with 12-s stage juveniles (J2)/cm3 soil. Incorporation of freeze-dried cyanobacterial powder into potted field soil at the rate of 0.2%, 0.4%, 0.6%, 0.8% and 1.0% (w/w) 5 days prior to tomato planting, reduced root galling, final population of M. arenaria and increased vegetative growth of tomato plants and root-mass production, compared with untreated control (P > or = 0.05). The beneficial effect of adding cyanobacterial powder into infested potted field soil increased exponentially with concentration up to 0.8%. Root galling and nematode population decreased by 68.9% and 97.6%, respectively at the highest dose (1%) of cyanobacterial powder compared with the untreated control. Addition of cyanobacterial powder into infested potted field soil at 5 days before planting was the most effective followed by 2 days before and at the time of tomato planting. We conclude that application rate and timing are important factors in the control of root-knot nematodes with O. chlorina.  相似文献   

17.
以一年生红叶石楠‘鲁班’盆栽苗为材料,研究了不同浓度NaCl胁迫下其生长、生理生化指标和叶片显微结构的变化。结果表明:在0.2%、0.4%和0.6%的NaCl胁迫下植株生长正常,而在0.8%、1.0%和1.2%的NaCl胁迫下植株生长受抑制;叶片最大荧光(Fm)、光系统II(PSII)最初光能转换效率(Fv/Fm)、光化学猝灭系数(qP)、表观光合电子传递速率(ETR)随NaCl浓度的升高而降低,其中在0.8%、1.0%和1.2%的NaCl胁迫下比对照显著降低;叶绿素a和叶绿素b含量及叶绿素a/b的比值随盐浓度的升高而降低;在0.2%、0.4%和0.6%的NaCl胁迫下,叶片中超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性较对照显著上升,而当NaCl浓度为0.8%、1.0%和1.2%时显著下降;在0.4%和0.6%的NaCl胁迫下叶片中丙二醛(MDA)的含量与对照相比显著降低,0.8%、1.0%和1.2%的NaCl胁迫下显著升高;叶中栅栏细胞在NaCl浓度为0.2%、0.4%和0.6%时逐渐纵向伸长且排列更紧密,浓度为0.8%、1.0%和1.2%时逐渐缩短且疏松,且栅栏组织厚度在0.6%的NaCl胁迫下达到最大。由此表明,红叶石楠‘鲁班’在NaCl浓度不高于0.6%的基质中能正常生长。  相似文献   

18.
The haptophyte microalga Tisochrysis lutea was heterotrophically grown in F2 medium with different combinations of pH and salinity. Growth, oil content and fatty acids (FAs) profile were determined under each set of conditions. The salinity was adjusted using NaCl at concentrations of 0.4, 0.6, 0.8, or 1.0 M, while pH was adjusted at 7, 8, or 9, and heterotrophic growth was performed using organic carbon in the form of sugar cane industry waste (CM). Fatty acid methyl esters (FAMEs) were identified by gas chromatography. The results showed that pH of 8.0 was the optimal for dry weight and oil production, regardless of the salinity level. At pH 8.0, growth at a salinity of 0.4 M NaCl was optimal for biomass accumulation (1.185 g L-1). Under these conditions, the maximum growth rate was 0.055 g L-1 d-1, with a doubling time of 17.5 h and a degree of multiplication of 2.198. Oil content was maximal (34.87%) when the salinity was 0.4 M and the pH was 9.0. The ratio of saturated to unsaturated FAs was affected by the pH value and salinity, in that unsaturated FAs increased to 58.09% of the total FAs, considerably greater than the value of 40.59% obtained for the control (0.4 M NaCl and pH 8.0).  相似文献   

19.
Porphyridium cruentum Näg. (clone 161) was found to grow best in medium containing between 0.45 M and 0.8 M NaCl. From studies done on growing cultures, the palmitic acid content of the cells decreased with increasing NaCl concentration of the medium. Conversely, when the culture was transferred from a 0.8 M NaCl medium to 0.2 M NaCl, the amount of palmitic acid in thePorphyridium cells increased with time of incubation and it contributed up to 64.5% of the total fatty acid content. There appears to be a negative correlation between the cellular content of palmitic acid and the growth lag. The oleic acid content varied only marginally with increasing NaCl concentration. The poly-unsaturated acid content (linolenic and arachidonic acids) decreased initially and then increased with NaCl concentration up to and beyond ca. 0.8 M NaCl respectively. At 1.5 M NaCl, the poly-unsaturated fatty acids amounted to 78.2% of the total fatty acids in the cell. For stationary phaseP. cruentum cultures, a similar relationship existed between fatty acids and NaCl concentration. However, palmitic acid was accumulated up to three-fold more when compared to the exponential culture grown in low salinity. In addition stearic acid was also found in significant quantities.  相似文献   

20.
In germination stage, decreased wheat (Triticum aestivum L.) seedling growth (mg per seedling) as affected by drought and salinity stresses is a well-known phenomenon. The heterotrophic seedling growth can be defined as a product of two components: (1) the weight of mobilized seed reserve (WMSR; mg per seed), and (2) the conversion efficiency of utilized seed reserve to seedling tissue (mg seedling dry weight (SLDW) per mg utilized seed reserve). The first component can be further divided into (1) initial seed weight (mg per seed), and (2) the fraction of seed reserve, which is mobilized (mg mobilized seed reserve per mg initial seed weight). The objective of this study was the identification of the sensitive seedling growth component(s) in response to drought and salinity stresses. Two experiments were separately conducted using various osmotic pressures (OP) induced by polyethylene glycol (PEG; 0–1.8 MPa, with interval of 0.2) in experiment 1 and by NaCl (0, 0.4, 0.8, 1.2 and 1.6 MPa) in experiment 2. Two wheat cultivars were used in each experiment. In both experiments, seedling growth, fraction of seed reserve utilization and weight of mobilized seed reserve decreased with increasing drought and salt intensity. However, drought and salinity stresses had no effect on the conversion efficiency. It was concluded that the sensitive component of seedling growth is the weight of mobilized seed reserve. Thus, appropriate efforts such as plant breeding programs should be focused on improvement of seed reserve mobilization in order to obtain increased seedling growth under drought and salinity stresses.  相似文献   

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