首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 187 毫秒
1.
采用恒温振荡吸附试验方法,研究了炭化秸秆对水体中氨氮和磷的吸附,并与粉煤灰和炉渣两种物料的吸附性能进行了对比。结果表明,炭化秸秆对氨氮和磷的吸附容量和吸附率小于粉煤灰、但大于炉渣,且3种物料对氨氮和磷的吸附容量,都随着吸附剂投加量的增加而减小;炭化秸秆和粉煤灰的吸附率随着吸附剂投加量的增加而增大,炉渣则减小;炭化秸秆和炉渣对氨氮和磷的吸附率随着pH值的增大而呈现不规则的增大趋势。3种物料对氨氮和磷的吸附容量受pH的影响很小,粉煤灰对氨氮的吸附容量在pH为6时最高,但在pH为4时炭化秸秆对氨氮的吸附容量最低。  相似文献   

2.
Abstract

The present study aimed to investigate the effects of K-type and Ca-type artificial zeolites on the growth and water and element absorptions of kidney bean (Phaseolus vulgaris L.), tomato (Lycopersicon esculentum Mill), maize (Zea mays L.) and beet (Beta vulgaris L.) in high sodic soil. Tottori sand dune soil, which was used as a control, was converted to high sodic soil mixed with salts. Each type of zeolite was mixed into the high sodic soil at rates of 0, 1, 2 and 5%. The results showed that kidney bean, tomato and maize died in high sodic soil 25–27 days after transplanting (DAT), whereas beet survived, although its growth was extremely suppressed at 26 DAT. The addition of Ca-type zeolite improved growth in all of the tested plants. Even 4 DAT the growth of beet was improved by recovery of water absorption, and growth of tomato was improved by recovery of Ca and K absorptions and cation balance, and restriction of Na absorption. Growth of kidney bean and maize improved at 11 or 13 DAT by recovery of water absorption and Ca and K absorptions. After 4 DAT, water absorption and P and K absorptions of beet were highly recovered compared with those of the other plants; beet growth improved to a large degree. The ameliorative effect of 5% Ca-type zeolite was lower than that of 2% in tomato, maize and beet because the excessive uptake of Ca restricted P transport from root to shoot, and high electrical conductivity of the soil solution restricted water uptake. Even 1% K-type zeolite addition suppressed growth of beet at 4 DAT, and the addition of 2% or 5% of K-type zeolite suppressed the growth of tomato and maize 11 or 13 DAT. Higher concentrations of HCO? 3 and CO2? 3, and pH of the soil solution of K-type zeolite treatments might inhibit water absorption by roots.  相似文献   

3.
土壤特性对保水剂吸水性能的影响   总被引:11,自引:1,他引:10  
该文测试了保水剂与砂壤土、壤砂土、砂黏壤土1和砂黏壤土2四种土壤混合后的吸水倍率,研究了土壤特性对保水剂吸水性能的影响,混合时土壤为风干土,保水剂与土壤的混合比例为0.5%。结果表明:与对照相比,保水剂与土壤混合后明显降低了吸水倍率,且随着吸水时间加长,降低幅度增大。吸水10 min后,吸水倍率下降14.4%~58.0%,70 min后,下降41.8%~90.2%。研究认为:吸水初期,吸水倍率主要受土壤孔隙特性的影响,随着吸水时间的加长,土壤溶液中离子增多,对保水剂吸水倍率产生了影响。土壤溶液中离子量与黏粒含量有关,黏粒含量高,土壤溶液中离子量大,反之则小,保水剂在黏粒含量高的土壤中的吸水倍率较在黏粒含量低的土壤中低。与土壤混合还改变了保水剂的吸水规律,对照中,吸水倍率随着吸水时间加长而加大,达到最大后趋于稳定;而在土壤中,短时间内吸水倍率达到最大,随着吸水时间加长,吸水倍率逐渐下降。  相似文献   

4.
中国南方两类典型土壤对五价锑的吸附行为研究   总被引:4,自引:0,他引:4  
研究我国南方两类典型土壤(红壤和棕色石灰土)对五价锑[Sb(V)]的等温吸附、动力学吸附-解吸过程,比较常用动力学方程对吸附动态曲线的拟合效果,采用分级提取方法分析锑在土壤中的结合形态。试验结果表明,酸性红壤对Sb(V)的吸附量(13.8μmol g-1)和吸附速度(0.58μmol g-1h-1)均大于棕色石灰土(9.19μmol g-1;0.38μmol g-1h-1),Sb(V)在红壤表面吸附是一个快速不可逆过程。锑主要以结合较强的Fe、Al氧化物结合态和残渣态存留在两种土壤中,专性和非专性吸附形态含量很低,也说明锑在土壤中以不可逆吸持为主。比较4种动力学吸附方程对实验结果的拟合程度发现,对于红壤而言,浓度较高的情况下Elovich方程(R2=0.96)的拟合性较好,浓度较低的情况下拟二阶动力学方程(R2=0.97、1.00)的拟合性较好;而对于棕色石灰土,在3种浓度下,双常数方程(R2=0.96、0.94、0.93)的拟合性均较好。  相似文献   

5.
不同大豆品种在养分吸收及产量上的比较   总被引:4,自引:0,他引:4  
采用盆栽试验方法对红丰11等四个大豆品种吸收利用氮、磷、钾养分的能力进行了比较研究。结果表明,在施肥一致的条件下,不同大豆品种对养分的吸收利用能力不同,养分利用率也不同,导致产量的差异。以红丰11养分吸收量最多,表现产量最高。  相似文献   

6.
Abstract

P type humic acid which has absorption bands near 615, 570, and 450 run due to the presence of dihydroxyperylenequinone (DHPQ) was investigated by gel-chromatography. Humic acid samples were fractionated using Sephadex G-50 as gel material and 0.1 n NaOH, with or without 1.5 m urea, as eluent. The absorption spectra of the effluent fractions were measured, and elution curves were drawn on the basis of the optical density at 600 nm.

In general, the intensity of the absorption bands due to DHPQ increased with increasing fraction number, accompanied by a change in effluent color from brown, greenish brown to green. Based on the elution curves, the effluent fractions of a humic acid containing a large amount of the green fraction were divided into six groups: B1, B2, BG, G1, G2, and G3. These fraction groups, especially the G groups and cercosporin, a dihydroxyperylenequinone pig ment, were compared by absorption spectroscopy, ultrafiltration, ultimate analysis, TLC, and gel-chromatography.

The green fraction was composed of a non-humic, relatively lower-molecular weight polymer containing a considerable amount of DHPQ nucleus, while the brown humic fraction still maintained the characteristic light absorption due to DHPQ. It may be tentatively con cluded that the green fraction is not only a co-extracted impurity, but is also firmly associated with dark-colored humic substances.  相似文献   

7.
复垦基质重金属污染的植物修复试验研究   总被引:1,自引:0,他引:1  
该文研究了粉煤灰加酒糟和粉煤灰加污泥两种基质对甘蓝、小白菜和油菜生长的影响,并通过计算吸收系数、转运系数和吸收模量讨论了甘蓝、小白菜和油菜对基质中重金属Cd、Cu、Zn的修复情况.结果表明:甘蓝、小白菜和油菜3种作物的吸收系数、转运系数和吸收量系数均随着时间的延长而增大,说明作物生长后期对重金属Cd、Cu、Zn的修复要好于前期;从不同作物对重金属Cd、Cu、Zn的修复情况看,甘蓝、小白菜和油菜对Cd具有良好的修复效果,其中小白菜对Cd的修复能力强于甘蓝和油菜,油菜对基质中重金属Cu具有一定的修复潜力,而甘蓝对Zn的吸收要好于小白菜和油菜;由于吸收模量考虑了作物地上部的生物积累量,也考虑了根层中重金属的总量,从而能从对重金属的实际修复效果方面更好地评价植株的吸收能力,是衡量植物修复重金属能力的一个理想指标.  相似文献   

8.
钾肥、覆膜对马铃薯硒素吸收分配及硒肥吸收率的影响   总被引:1,自引:0,他引:1  
采用田间试验方法研究了钾肥及覆膜对马铃薯硒素吸收分配的影响.结果表明:地膜覆盖及钾肥的施用提高了收获期马铃薯全株及块茎干物质产量;钾肥的施用显著提高马铃薯全株及块茎硒素含量与吸收累积量.钾肥与硒肥配合施用,使块茎硒素含量达0.148 mg·kg-1的富硒水平,对块茎硒素的富集有正交互效应,使收获期全株硒肥吸收率达17.8%,比单施硒肥提高1.5个百分点,块茎硒肥吸收率7.1%,提高2.7个百分点.覆膜对马铃薯全株、块茎硒含量及全株硒素吸收量无显著影响,但可显著提高块茎硒素累积量.覆膜硒肥配合,收获期全株硒肥吸收率20.0%,提高2.2个百分点,块茎硒肥吸收率10.1%,提高3.1个百分点.覆膜可显著促进硒素在体内由茎叶向块茎的转移.收获期,覆膜硒素运转率53%,提高10.1个百分点.  相似文献   

9.
20 0 2~ 2 0 0 3年 ,根据生长季节分四次测定了君子兰年周期内植物体营养元素含量 ,并开展君子兰各物候期的肥水吸收对比试验 ,结果显示 :开花君子兰对水分及营养元素N、P、K、S的吸收大于不开花的君子兰 ;君子兰在夏季 (6~ 9月 )营养需求降低 ,而且其植物体内各元素含量因物候期而异 ,其季相变化趋势与营养吸收的变化规律一致  相似文献   

10.
芦笋矿质元素吸收特性研究   总被引:2,自引:0,他引:2  
研究了芦笋不同生长时期干物质积累和矿质元素吸收特性。结果表明,芦笋在采笋期干物质积累占全年总积累量的26.2%。嫩茎为该时期的干物质积累中心,积累量占采笋期积累量的69.7%。母茎生长期干物质积累占全年总积累量的73.8%,母茎为该时期的干物质积累中心,积累量占这一时期积累量的70.9%。在各种矿质元素中,芦笋植株吸收钾最多,其次为氮。对氮、磷、钾、钙、镁的吸收比例为3.33︰1︰4.77︰0.52︰0.23。钾在采笋期和母茎生长期的积累量基本相同;氮、铜、锌主要在采笋期积累;磷、钙、镁、铁、锰则主要在母茎生长期积累。根据芦笋矿质元素吸收特性提出了芦笋不同生育阶段的施肥建议。  相似文献   

11.
汞在泥炭上的吸附动力学研究   总被引:6,自引:0,他引:6  
采用批次法研究了汞在三江平原泥炭和吉林双阳泥炭上的吸附动力学特征及温度、pH值对吸附的影响,实验表明:在相同的实验条件下,三江平原泥炭对汞的吸附速率小于吉林双阳泥炭;温度升高加快泥炭吸附汞的反应速度;两种泥炭对汞的吸附速率受pH值的影响明显且都在pH6.0左右具有最大的吸附量;在酸性介质内,介质的pH值升高,利于泥炭对汞的吸附;两种泥炭对汞的吸附动力学用Hill方程描述最为合适。湿地泥炭土壤较高的吸附容量,以及湿地低温和适当的pH都利于湿地对汞的累积。  相似文献   

12.
黄土高原氮磷肥水平对旱作冬小麦产量与氮素利用的影响   总被引:10,自引:0,他引:10  
为了探求氮磷肥合理和高效利用的科学依据,以黄土高原中南部的旱地农田生态系统长期定位试验为基础,选取了不同施氮和施磷水平,探讨了不同降水年份,氮磷肥用量对作物产量、氮素吸收和利用等相关指标的影响。结果表明,平水年份施氮水平在0~45?kg/hm2和干旱年份在0~90?kg/hm2范围内作物产量和收获指数均随施氮水平的增加迅速提高,超过这个范围后则差异较小;施磷水平在0~45?kg/hm2之间产量增幅较大,干旱年份施磷量反而降低了收获指数;吸氮量随氮磷用量变化与产量有相似趋势;不同降水年份施氮水平对氮素收获指数均无显著影响,而施磷水平在干旱年份对氮素收获指数没有显著影响,平水年份则随施磷水平增加而有所提高;平水年份氮素利用效率随施氮水平的增加呈降低趋势,而干旱年份施氮水平对冬小麦氮素利用效率没有显著影响,施磷则在不同降水年份均比不施磷肥的处理提高了冬小麦的氮素利用效率,但较高的施磷水平之间差别较小。冬小麦产量和吸氮量之间有显著相关关系,干旱年份更接近二次曲线,氮素利用效率随吸氮量增加呈直线下降趋势。旱作农田氮磷配施及采用适中的氮磷肥用量可以促进作物对氮素的吸收,同时得到较高的氮素利用效率,从而使冬小麦获得较高的产量和较强抵御干旱的能力。  相似文献   

13.
It has been established that the plant leaves and other above‐ground parts are capable of absorbing chemicals and nutrients. However, there is great paucity of information regarding the mechanisms of ion uptake by leaves and their transport to other parts. Equally not well understood is the phenomenon of retranslocation of elements from one leaf to another during the different stages of plant growth. The results of investigations carried out in this area of foliar uptake and translocation in the last few years are described. In this review, the importance of future studies to investigate the mechanisms involved in foliar transport, the influence of plant growth substances, and the effectiveness of timely supply of specific nutrients during the grain development stage, is stressed.  相似文献   

14.
A pot trial was conducted to clarify the interactions of molybdenum (Mo) and selenium (Se) fertilizers on uptake, harvest index and recovery of Mo and Se by pepper crop (Capsicum frutescens L.). Mo was applied at three rates (0, 0.15 and 0.3 mg kg?1) and Se at three rates (0, 0.4 and 0.8 mg kg?1) in soil. Appropriate application of Mo increased Se concentrations in pepper fruit, stem, leaf and root especially in the presence of Se fertilizer. Appropriate application of Se increased Mo concentrations in pepper fruit, stem, leaf and root particularly in the presence of Mo fertilizer. Both Mo and Se had beneficial effects on harvest index and recovery of Mo and Se. These results indicated that there is significant synergetic effect on Mo and Se absorption and translocation, and co-application of these two elements is necessary to produce Mo and Se-rich pepper.  相似文献   

15.
Phosphite (     ; Pi) uptake in cell suspension culture, information on how Phi affects the Pi uptake of intact plants remains to be determined. The present study was conducted to investigate the effect of Phi on Pi absorption of intact komatsuna plants ( Brassica rapa var. peruviridis cv. Ajisai) in hydroponic culture. Phosphite markedly decreased Pi absorption of the intact komatsuna plants under both low (0.05 mmol L−1 ) and high (0.5 mmol L−1) Pi supply, although the growth (both shoots and roots) and water uptake of the high Pi-supplied plants was not affected by Phi. The inhibiting effect of Phi was small at 0.2 mmol L−1, but became large at 2 mmol L−1. Using relatively large seedlings (28 days old) to better assess the influence of Phi on Pi absorption early in the treatment, the results indicated that there was an immediate decrease in Pi absorption within the first 2-day period of Phi treatment when the water absorption of the plants was not affected. Taken together, the results suggested that there was a strong inhibiting effect of Phi on Pi uptake of intact komatsuna plants and this effect is exerted most likely by competition between Phi and Pi at uptake level. We speculate that the application of Phi to plant roots in an environment that is unfavorable for Phi-to-Pi conversion (e.g. hydroponic culture) may need to increase the amount of required Pi fertilization of plants to compensate for the reduction in Pi uptake by Phi. Further research is needed to confirm our results.  相似文献   

16.
Abstract

Analyses of 6 reference plant tissue samples were completed by 22 commercial and university laboratories across the U.S and compared. Cooperators were requested to analyze samples of apple leaf (Malus domestica Borkh.), grape petiole (Vitis labrusea L.), pecan leaf (Carya illinoensis (Wangenh.)K. Koch), snapbean leaf (Phaseolus vulgaris L.). eweet corn leaf (Zea mays L.), and rose leaf (Rosa hybrida) for the elements comprising a routine analysis. Each laboratory was requested to use their routine analytical procedures, with no attempt to standardize these methods. Close agreement between laboratories occurred with analyses of N, P, and Mg in which 80%, 69%, and 68% of the laboratories reported values within ± 5 % of the mean, respectively. Close agreement was also found for Mn and Zn, with 81% of laboratories reporting Mn and 73% reporting Zn values within ± 10% of the mean. Variation between laboratories was greater for K and S, in which 46% and 30% of the laboratories reported values within ± 5% of the mean, respectively. Values for Fe, Cu, and B were also variable, with 46%, 48%, and 46% being within ± 10% of the mean, respectively. Similiar values were reported for Ca, Mg, Mn, and Zn by laboratories using either AA spectrophotometer (AA) or ICP emisssion spectrometer (ICP) as the primary instrument. Lower values were reported by those using ICP versus AA for determination of Cu and Fe.  相似文献   

17.
毕桂英 《水土保持通报》1998,18(2):31-34,35
水样中微量元素的测量是研究元素迁移的一项基础工作。通常用火争原子吸收和法测定水样中微量元素,当样品中元素含量较低时需用甲基异丁基甲酮萃取后测定。该文对这一方法进行了改进,采用浓缩水样以提高街测元素的含量,并加入二氯化钙作为释放剂来消除硅的干扰。  相似文献   

18.
利用ASD地物光谱仪对不同浓度下小球藻、聚球藻及其混合藻的反射光谱进行测量,得到3组藻类在不同叶绿素a(Chl-a)浓度下的反射光谱,同时进行了Chl-a浓度测量。利用Matlab软件神经网络模型中的径向基函数对得到的高光谱数据进行高光谱曲线拟合,在拟合结果基础上,提取小球藻在652nm处、聚球藻在609nm处以及混合藻在652nm和609nm处的光谱吸收指数(SpectralAbsorptionFeatureParameter,SAFP)建立了两种单一藻类的定量模型,单一小球藻Chl-a最优定量模型为吸收峰深度模型Chl-a=10.059e713.97H,聚球藻的Chl-a最优定量模型为吸收峰斜率模型Chl-a=3×1012K2+1×107K+56.555。并在对两种单一藻类的定量模型研究基础上用光谱吸收指数对该两种藻的混合藻进行了Chl-a浓度分离。通过对比模型计算结果的均方根误差(RootMeanSquareError,RMSE),除吸收峰对称度模型分离结果不太理想外,吸收峰深度分离模型、吸收峰斜率分离模型、吸收峰光谱吸收指数(SAI)分离模型的分离结果都很好,分离效果最好的为SAI分离模型。  相似文献   

19.
用盆栽试验研究了不同含量硒酸钠对4种蔬菜(小白菜、芥菜、生菜和菠菜)生长、硒吸收及转运特征的影响,为富硒蔬菜的开发和硒污染土壤的植物修复提供理论依据。结果表明,低含量的硒酸钠态硒(〈1.45mg·kg-1)可促进4种蔬菜的根和茎的生长,增加其生物量,但过量硒酸态硒(〉2.04mg·kg-1)对蔬菜有明显的毒害作用。供试的4种蔬菜地上、地下部硒含量均随外源硒含量的增加显著增大(P〈0.01),其中小白菜和芥菜地上硒含量是生菜和菠菜的5.8~8.5倍;4种蔬菜地下部硒含量的大小依次为芥菜〉小白菜〉菠菜〉生菜。所有施硒处理小白菜、芥菜和生菜地上硒含量约是地下硒含量的1~2倍,菠菜地上与地下硒含量与土壤硒含量高低有关,当土壤硒含量〈5.02mg·kg-1时,菠菜的地下硒含量大于地上部,当土壤中硒含量〉5.02mg·kg-1时,地上部硒含量大于地下部。4种蔬菜相比较,地上部硒富集系数(BCFshoot/soi)l值的大小依次为小白菜≈芥菜〉菠菜〉生菜,地下部富集系数(BCFroot/soi)l值的大小依次为芥菜〉小白菜〉菠菜〉生菜;以小白菜对硒的转运系数(TF)值最大,菠菜最小。供试的4种蔬菜中,小白菜因具有较高的将六价硒从地下转运到地上的能力,且拥有较高的地上生物量,可作为富硒蔬菜和硒污染土壤修复植物。  相似文献   

20.
一次性施用控释肥对水稻根系活力及养分吸收特性的影响   总被引:10,自引:1,他引:10  
采用盆栽试验,研究了一次性施用控释肥对水稻根系活力及养分吸收特性的影响。结果表明,在等养分量下,控释肥BNCRF和BRCU处理较专用肥分次施用的SNRSF处理能提高水稻生育前期、中期根系伤流强度,显著提高全生育期伤流液的氨基酸态氮输出强度;明显增加了根系总吸收面积和有效吸收面积。同时,BNCRF处理在前、中期氮、磷吸收速率显著增强,BRCU处理仅在生育中期显著提高。采用低钾控释肥BLCRF处理,水稻前期伤流强度、氨基酸态氮输出强度及吸收面积均较小,但中、后期明显增高,氮、磷吸收速率与高钾含量的SNRSF处理相当。说明一次性施用控释肥能显著增强根系活力,提高生育中期养分吸收速率,改善水稻根系生理功能。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号