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1.
《林业调查规划》2016,(6)
在霍格兰配方基础上,依据广西岑溪软枝油茶自身的营养吸收分配规律,调整营养液配方,采用砂培方法开展软枝油茶苗木缺素试验。监测油茶在N、P、K、Ca、Mg、Fe、S营养元素缺失条件下苗木的形态特征、叶片营养元素含量和生理特性(硝酸还原酶活性以及过氧化物酶活性),结果表明,各缺素处理均对油茶苗木的生长产生一定抑制作用,主要表现为叶片失绿,无光泽,苗木纤弱等现象,其中表现症状突出为缺铁、缺氮、缺钙处理。通过叶片营养的主成分分析,叶片综合养分从高到低次序为:全素-Mg-S-Ca-Fe-K-P-N蒸馏水,N、P、K元素为幼苗养分吸收与分配的主要限制因子。不同缺素处理对叶片叶绿素(a+b)总含量、硝酸还原酶活性以及过氧化物酶活性大小影响最为明显的是缺氮和缺铁处理,缺钾处理下这些指标较全素处理略高。 相似文献
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试验选取当年生的火力楠的实生苗为试验材料,采用正交试验设计方法L9(34),研究苗木生长各阶段氮、磷、钾的不同配施处理下火力楠的叶子的生长指标(苗高、地径)和生理指标(细胞膜透性、丙二醛(MDA)、叶绿素、可溶性蛋白质含量)的变化规律。结果表明:在不同氮、磷、钾配施处理下,P对苗高、地径起主要作用,N、K次之,在N3P1K3配施下苗高地径的增长均不理想,在N2P2K2配施下增长最好;从N1→N3细胞膜透性呈减小趋势,K1→K3细胞膜透性呈增大趋势,N为主要影响因素,K次之,P最小;影响丙二醛(MDA)因素主到次为N→P→K,N、P、K越多MDA越少;影响叶绿素的因素主到次为N→P→K,N、P、K越多叶绿素含量越少,即在N1P1K3下叶绿素最多,比CK处理的叶绿素含量高32.26%;影响可溶性蛋白质含量因素主到次为N→K→P,K表现不规律,P表现不明显。 相似文献
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《中南林业科技大学学报(自然科学版)》2016,(3)
以2 a生钩栗苗为试验材料,采用N、P、K三因素四水平正交试验设计,研究配方施肥对2 a生钩栗苗木生长和生理特性的影响,旨为钩栗壮苗生产提供技术依据。结果表明,苗高生长最优、叶片可溶性糖含量最高的氮、磷、钾配方为N_1P_2K_2;地径生长最优、生物量最大、叶绿素含量最高、叶片可溶性蛋白含量最高的氮、磷、钾配方为N_2P_2K_1。综合考虑苗木的生长,最优的配方组合是N_2P_2K_1,即钩栗氮磷钾施肥量分别为每株6 g、6 g和3 g。 相似文献
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采用盆栽方法,对白桦（Betula platyph ylla）、落叶松（Larix olgensis）苗木分别进行纯栽和二者混栽,通过研究混栽对白桦、落叶松苗木生长、生物量、叶片养分、土壤养分的影响,探讨混交林种间互作机制.结果表明：混栽能促进两树种苗木的生长,一个生长季内混栽的白桦苗木苗高、地径、生物量分别较纯栽提高7％、20％和97％（P＞0.05）,落叶松分别提高6％、15％和185％（P＜0.05）.两树种养分吸收动态存在明显差异,混栽时,白桦对氮素吸收集中在7-8月,对磷、钾吸收集中在6-7月;落叶松对氮素吸收集中在6-7月,磷集中在8-9月,钾集中在7-8月.混栽时两树种苗木对营养元素的吸收存在时间差异,白桦对土壤氮的改善作用及落叶松对磷营养的改善可能是导致混栽增产的原因. 相似文献
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施用氮、磷肥对旱冬瓜苗木生长的影响 总被引：3，自引：1，他引：2
以Hoagland液为母液,调节母液中氮磷的浓度作全磷缺氮、全磷低氮、全氮缺磷、全氮低磷4种营养液处理对旱冬瓜盆苗苗木生长影响的试验,并以清水处理作对照,结果表明:在旱冬瓜的盆苗培育期,缺磷、仅施用氮肥时,会抑制其苗木的生长,旱冬瓜苗木的茎生物量、叶生物量、地上部分总生物量、细根生物量、地下部分总生物量分别比清水处理下降了66 %、69 %、68.5 %、65 %、59.7 %,在其培育期施用低磷全氮肥能促进旱冬瓜苗木根系的生长,但不能增加其苗木地上部分的生物量;施用全磷肥能明显促进旱冬瓜苗木的地径及苗高生长,增加苗木地上和地下部分的生物量,它们依次比清水处理增加了46.3 %、7.2 %、73.3 %、51.6 %.试验结果还表明,旱冬瓜苗木的地下部分与地上部分的生物量比例＜1时,反映此期间需对其苗木加强光照.在旱冬瓜的育苗期其苗木仅需供给全磷营养液和充分的光照即可,不需要补充氮肥. 相似文献
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施肥对盆栽杉木苗土壤养分含量的影响 总被引：4，自引：0，他引：4
研究施肥对1年生(1 a)与2年生(2 a)杉木苗盆栽土壤养分含量的影响.结果表明:在氮、磷营养亏缺的酸性黄红壤上,随着氮肥施用量的增加,1 a苗木盆栽土壤pH值、全钾含量下降,全氮、水解氮、水溶性钙镁含量增加,全磷、有效磷、速效钾变化不明显.由于局部尿素浓度过大直接导致幼苗受伤,影响了成活率.而2 a苗木的土壤则是全氮、水解氮、水溶性钙镁含量呈上升趋势,全钾、速效钾含量和pH值下降,有机质和全磷含量变化不明显.有效磷含量与pH值呈明显负相关,表明pH值下降导致闭蓄态磷活化,促进了2 a苗木的生长.在氮、磷营养亏缺条件下,施磷量的增加使得1 a苗木土壤全磷、有效磷、速效钾含量、pH值增加,全钾、水溶性钙镁含量则下降,有机质、水解氮没有明显变化.养分含量与生长指标的相关分析表明:施用磷肥解除了1 a苗木磷素营养亏缺,显著促进了苗木生长;而对2 a苗木,施磷肥使土壤中的全磷、有效磷增加,全钾含量下降,pH值、有机质、全氮、速效钾、水溶性钙镁没有明显变化.对养分含量与生长指标的相关分析表明:施磷肥对2 a苗木生长没有促进作用,而且使土壤营养平衡进一步失调,苗木仍处于营养亏缺状态.在氮素营养充足、磷素亏缺的营养条件下,随着氮磷复合肥施肥量的增加,2 a苗木中的全氮、全磷、水解氮、有效磷增加,速效钾含量下降.施用氮磷复合肥可促进苗木对速效钾的吸收利用,导致苗木的光合产物向叶和茎部转移. 相似文献
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通过盆栽试验,采用尿素、过磷酸钙各4个水平共8个处理,研究N、P肥对湿加松幼苗的生长效应.结果表明,尿素和过磷酸钙均对湿加松生长有显著影响;各处理对湿加松地径生长的影响在9-12月差异显著,N-1处理地径最大,P-2处理次之;各处理对冠幅生长的影响在7-11月有显著差异,7月以N-2处理冠幅最大,8-11月则以P-2处理最大;各处理对苗高生长的影响差异不显著.对湿加松苗木生物量和植株N、P含量的分析表明,施用一定量的尿素、过磷酸钙可改善植株的养分状况,过量施用则不利于N、P的正常吸收;湿加松苗木最佳施肥组合是每株施尿素6g＋过磷酸钙30 g＋氯化钾15 g. 相似文献
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用0、50、100、200、300mg/L的稀土处理巨尾桉幼苗,以探讨其对巨尾桉苗木生长的影响及生理效应.结果表明稀土能促进苗高和地径的生长.提高根系活力,增加叶片气孔密度和栅栏细胞密度,提高叶片N、P、K以及蛋白质含量.提高苗木叶绿素含量和净光合速率. 相似文献
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指数施肥对山桃稠李播种苗生物量及养分动态的影响 总被引：3，自引：0，他引：3
采用常规施肥(CF)、指数施肥(EF)和2倍指数施肥(DEF)3种施肥处理,研究大田条件下不同施N肥处理对山桃稠李1年生播种苗生物量和养分(N,P,K)含量动态及养分承载的影响。结果表明:1)生长季结束后,EF和DEF处理单株生物量分别为37.00g和35.60g,比CF处理(27.10g)分别增加36.5%和31.3%(P<0.05);2)苗木生长高峰期第9～11周,EF和DEF处理单株苗木N含量增量分别为0.28mg和0.17mg,均高于CF处理(0.03mg)(P<0.05);3)EF和DEF处理均提高了播种苗体内N养分承载,生长季结束时,单株苗木N含量分别为0.69g和0.73g,均显著高于CF处理(单株0.44g)(P<0.05);4)EF,DEF处理促进了苗木对P,K吸收,生长季中P,K的吸收速率顺序均为DEF>EF>CF。生长季结束时,EF和DEF处理P质量分数较CF处理分别高28.4%和9.0%;2种指数施肥处理K质量分数较CF处理高12.5%和19.9%。采用指数施肥有效促进山桃稠李播种苗生长,可改善苗木营养状态,同时苗木造林成活率和生长效果较佳。 相似文献
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This study presents data on the biomass and net aerial primaryproductivity (NAPP) of two contrasting East Anglian salt marshes.One site was at Tollesbury, Essex where the marshes are of theestuarine type and are subject to marsh degradation and erosionwhile the other site was 130 km to the north at Stiffkey, Norfolkwhere the barrier-type marshes are still actively developing withno signs of erosion. The NAPP was determined by the method ofSmalley with quadrats being harvested monthly with replacement.At the lowest levels at Tollesbury there was Pioneer Marshwhich was dominated by a mixture of Salicornia spp. and Astertripolium. At higher levels at Tollesbury there was LowerMarsh which was dominated by a mixture of Atriplex portulacoides andPuccinellia maritima. Over the four years of the studyPuccinellia became the dominant species following a markeddecrease in the extent and vigour of Atriplex. At Stiffkey theMiddle Marsh was at a much higher level and the vegetation waspredominantly a short dense sward with Atriplex portulacoides,Puccinellia maritima and Limonium vulgare together with smallerquantities of Armeria maritima and Plantago maritima. The meanNAPPs over three years of the Pioneer and Lower Marsh atTollesbury (467 & 519 g m-2 yr-1respectively) were similar butin 1993 the NAPPs recorded at Tollesbury were higher than thoserecorded at Stiffkey (625 & 583 compared with 458 g m-2yr-1).Smalleys method is difficult to apply to communities wherespecies dominance is variable, especially when dominance isshared between species with markedly different growth patterns.The results for NAPP obtained from the salt marshes at Tollesburyand Stiffkey are discussed in relation to results obtained byother workers from comparable areas in England and theNetherlands. Attention is also drawn to the possibly largerbelow-ground component of production that is frequentlyoverlooked. The importance of salt marshes in relation to othercoastal communities lies in the export of a proportion of theorganic matter produced and this mainly depends on theabove-ground production. 相似文献
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Responses of swamp bay,Persea palustris,and avocado,Persea americana,to various concentrations of the laurel wilt pathogen,Raffaelea lauricola 
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下载免费PDF全文 M. A. Hughes S. A. Inch R. C. Ploetz H. L. Er A. H. C. van Bruggen J. A. Smith 《Forest Pathology》2015,45(2):111-119
Laurel wilt, caused by the fungus Raffaelea lauricola and transmitted by the exotic ambrosia beetle Xyleborus glabratus, has killed members of the Lauraceae plant family throughout the southeast United States. A series of experiments were conducted to examine the effects of inoculum concentration on the development of laurel wilt in swamp bay, Persea palustris, and avocado, Persea americana. In each experiment, host plants were inoculated with aqueous suspensions of 102, 103, 104 or 105 conidia of R. lauricola, and plants were rated periodically for external symptom development (wilting and foliar dieback). At the end of experiments, plants were rated for internal symptoms of the disease (discoloration of sapwood) and assayed for R. lauricola on a semi‐selective medium. Symptom severity in swamp bay was significantly lower for the 102 treatment than at higher (103–105) concentrations, whereas 102 and 103 conidia caused less disease than 104 and 105 conidia in avocado. At the lowest inoculum concentration, 67% of the swamp bay plants and 20% of the avocados died by the time the respective experiments were terminated. The pathogen was recovered from a high proportion of the symptomatic sapwood of swamp bay (100%) and avocado (94%), and sapwood discoloration and recovery of R. lauricola from inoculated stems of swamp bay were highly correlated with recovery of the pathogen and symptom development in roots. Clearly, swamp bay and avocado are very sensitive to R. lauricola. The ability of only 100 conidia of this pathogen to kill these hosts suggests that few individuals of X. glabratus or other ambrosia beetles that carry low levels of the pathogen would be sufficient to transmit conidia that infect and lead to disease development. The results are also relevant to the development of disease‐tolerant host selections, as they indicate levels of the pathogen appropriate for use in screening plants for disease resistance. 相似文献
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采用野外调查与查阅标本相结合的方法,对东莞蕨类植物区系及其分布特点进行研究,结果表明:东莞市有蕨类植物37科66属125种,其区系特点为:①分布区类型在科、属、种的水平上皆以热带、亚热带性质为主,占各自总数的64.87%、75.76%与61.60%。②科与属的分布区类型显示出东莞蕨类植物区系从热带向亚热带过渡的性质,与温带蕨类植物区系的联系较弱;在种的水平上,温带成分占总数的28.80%,呈现出热带蕨类植物区系向温带蕨类植物区系过渡的特点。③在种的水平上热带亚洲分布及东亚分布类型构成了东莞蕨类植物区系的主体,各占38.40%和20.80%。④与周边4个地区的比较中,与深圳的相似性为最高,与乐昌的相似性为最低;总体上,东莞蕨类植物区系与周围地区关系较为密切。 相似文献
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We carried out an ethno-medico-biological investigation in the interior of Bhadrak district, Odisha, India to explore the therapeutic use of traditional plants/animals by local inhabitants. The villagers and rural people used plant and animal species as medicine. We recorded therapeutic use of 18 plant species of 13 families and 12 animal species of seven taxonomic categories. Different plant/animal parts like bark, leaf, flower, seed, stem, root, whole plant, oil, blood, milk, urine and flesh were reported as used in raw or cooked form against 17 specific diseases. Prominent diseases treated by plant/animal remedies were asthma, cardiovascular ailments, diabetes, epilepsy, jaundice, malaria, skin disorder and rheumatism. This study provides a better database for future studies. 相似文献
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系统论述卫片色调与坡向、坡度、坡位、林分龄组、郁闭度的关系 总被引：2，自引：0，他引：2
当前 ,人类赖以生存的地球资源与环境面临越来越严重的威胁。如何迅速、宏观、准确、周期性监控资源和环境 ,已被各国和国际环境组织所重视 ,而卫星遥感就具有迅速、宏观、准确、周期性等特点 ,已被各国应用。内蒙古大兴安岭林业调查规划设计院于 1996年松岭林业局森林资源二类调查时就采用了这个先进的卫星遥感技术。现将影响卫片色调的坡向、坡度、坡位、林分龄组、郁闭度的五大因素进行系统研究 ,找出其相关规律 ,为今后的森林资源调查建立标志和目视判读解译标志提供理论依据 相似文献
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Lewis Clifford E. Burton Glenn W. Monson Warren G. McCormick W. C. 《Agroforestry Systems》1983,1(4):277-297
Agroforestry Systems - Native forages of southern United States are frequently low in nutrients and poorly digestible, while improved pastures are the opposite. Since this area produces rapid... 相似文献