【作者】 张敬敏；

【导师】 刘春生； 邢尚军；

【作者基本信息】 山东农业大学 ， 植物营养学， 2011， 博士

【摘要】 本试验针对杨树栽培中存在的问题,借助农业生产中理论研究的成果,将之应用于林业生产中,对杨树水肥、覆膜、断根和配施有机肥等多项超高产关键栽培技术进行系统深入研究,以了解杨树生命活动的规律,改善林地肥力状况,提高其杨树生长量。通过研究得出以下结果:1.水肥调控:相同水分下,与单施无机肥相比,配施腐殖酸不同程度的提高了杨树根系活力、叶绿素含量,在生长前期可不同程度的提高硝酸还原酶(NR)活性。低水条件下,配施腐殖酸可降低气孔导度(Gs)和蒸腾速率(Tr),提高水分利用效率(WUE),提高脱落酸(ABA)含量,提高杨树的抗旱性;在常规和高水分条件下,腐殖酸的施用不同程度的提高了气孔导度(Gs)和光合速率(Pn),显著降低了ABA含量。随水分用量的提高和腐殖酸的施用,杨树对活性氧的清除能力和渗透调节能力增强,叶片和根系的生长素(IAA)、赤霉素(GA)含量和玉米素(ZT)可不同程度的提高,促进了杨树生长。生长后期,相同水分下配施腐殖酸与促进了杨树对土壤NPK的吸收,与相同无机肥用量的单施无机肥相比,降低了土壤硝态氮、速效磷和速效钾含量,提高铵态氮含量,减少氮的损失,施腐殖酸还可提高土壤有机碳量、胡敏酸和富里酸含量,增加胡/富比,提高多酚氧化酶和脲酶活性。低水条件下,配施腐殖酸处理的根、茎、叶重、总生物量和植株氮磷钾含量与单施无机肥处理差别不大,在常规水分下,总生物量配施腐殖酸比单施无机肥平均提高了18.75%,高水条件下,分别提高了55.28%和15.34%,说明在常规水分和高水下施腐殖酸对杨树生长有显著影响,但另一方面杨树在高水高肥下其生长量也是有限的。2.覆膜调控:覆膜处理提高SOD、POD活性,MDA积累也较少。覆膜处理蛋白降解较慢,因而脯氨酸和游离氨基酸也比未覆膜处理低,说明覆膜可降低杨树后期叶片细胞膜脂的过氧化程度,提高膜的稳定性,延缓衰老。覆膜减少硝态氮随水流失,提高氮肥利用率,速效磷、速效钾、有机质分别提高了46.60%、6.09%和35.60%。覆膜提高过氧化氢酶、淀粉酶和脲酶活性,可使细菌、真菌和放线菌数量分别提高144.73%、63.45%和10.07%,微生物总量提高101.65%,提高了土壤肥力。覆膜比未覆膜处理胸径提高了30.15%,树高提高了10.75%,材积提高了33.93%。覆膜处理可明显提高根枝叶了氮、磷和钾的含量。3.断根调控:断根可提高生长后期叶片SOD活性,降低POD活性和MDA含量,四侧断根处理的MDA含量又高于两侧断根。近根处断根和四侧断根降低了杨树生长后期可溶性蛋白和游离氨基酸的含量;脯氨酸含量四侧断根高于CK,两侧断根低于CK。硝态氮含量60cm断根高于CK,80cm和100cm断根低于CK。铵态氮和速效磷等含量各断根处理低于CK。同样断根距离,硝态氮、铵态氮和速效K四侧断根含量高于两侧断根,而速效磷为两侧断根高于四侧断根。断根可提高过氧化氢酶和脲酶活性,降低多酚氧化酶活性,提高细菌、放线菌、真菌和微生物总量,都以四侧断根处理高于两侧断根处理。断根较未断根处理可明显提高杨树的胸径和树高,从材积上看,以8-2处理年生长量最大;10-2和10-4次之;再次是6-2、8-4和6-4处理,但各断根处理材积年增长量都高于CK,断根还较CK可显著提高了根茎叶内的某些养分含量。可见,合理的断根处理不仅未影响正常生长量,而且还有相应的提高,所以断根技术对提高杨树产量是可行的。4.有机肥调控:施有机肥可提高生长后期叶片SOD活性,降低MDA含量,提高可溶性糖和可溶性蛋白含量,降低游离氨基酸含量,稳定叶片质膜完整。配施有机肥处理氮磷钾各处理没有明显的规律,但施有机肥各处理可明显提高了土壤有机碳、胡敏酸碳、富里酸碳、胡富比和E4/E6值,增加了土壤腐殖质的活性,有利于土壤中的腐殖化过程。不同施有机肥处理可提高过氧化氢酶、多酚氧化酶、过氧化物酶和脲酶活性,可显著提高土壤细菌、放线菌、真菌和微生物总量。各施有机肥处理显著提高了杨树的胸径、树高和材积的年生长量,材积增量处理1增加了40.68%,处理2和4分别增加了38.41%和35.08%,处理3增加了33.60%,最后是CK,增加了28.14%。说明施用有机肥配施无机肥对杨树生长有明显的促进作用。更多还原

【Abstract】 To solve the problem in poplar planting, in aid of agriclutural research achievement, system research were carried out in forest cultivation including key techniques of water and fertilizer regulating, root regulating, plastic mulch, organic fertilizer et al. The study tried to explore the regular of plplar growth, improve the forest fertility and increase the poplar yield. The results were as fellows:1. Water and fertilizer interactive: Under the same water level, the content of chlorolhyll and root activity was increased in application of humic acid compared with inorganic fertilizer. The NR activity was increased in application in earlier stage. Application of humic acid fertilizer decreased the Gs and Tr, increaed the WUE and ABA under low water condition; however, it is increased the Gs and Pn, decreased the content of ABA significently in regular and high water level.With the increasing of water level and application of humic acid, the content of IAA GA and ZT increased in varying degree in leaf and root. Application of humic acid also enhanced the activity of active oxygen elimination and the osmoregulation.Under the same water level, the poplar total absorbtion of N、P、K was increased by application of humic acid compared with inorganic fertilizer, therefore, the contents of nitrate nitrogen and available P、K were low in soil, but it can increased the content of ammonium nitrogen, which might reduce the loss of N from soil. The application of humic acid also increased the contents of total C, humic acid、fulvic acid and the ratio of humic acid to fulvic acid、polyphenol oxidase enzyme and urease enzyme.Application of humic acid have little effect on weight of root、stem、leaf and total weight of poplar under low water treatment, have significent effect under regular and high water treatment however, and high water treatment increase the most.2. Plastic membrane mulch: Plastic membrane mulch treatment increased the SOD POD activity, decreased the content of MDA. Protein are degradation slow, and Pro and free amino acid are low in mulch treatment, It can be concluded that plastic membrane mulch can decreased the degree of cell membrane lipids peroxide, increased the cell membrane stability, and put off the poplar aging. Compared with no mulch treatment, plastic membrane mulching can decrease the loss nitrate nitrogen and increased the utilization ratio of N in treatment. It also can increased the available P, K and organic matter by 46.60%、6.09% and 35.60% respectively, and can increased the bacterium, actinomycetes, fungus and microorganism by 144.73%, 63.45%, 10.07% and 101.65% respectively.As for the amount of growth, compared to no mulch, plastic membrane mulching increased DBH、tree height and volume of timber by 30.15%, 10.75% and 33.93% respectively, and also increased the NPK content in root、stem and leaf. It is thus clear that the application of plastic membrane mulch have active effects in poplar growth.3. Root cutting: Root cutting can increased the activity of SOD, decreased the MDA content. MDA are higher in four side root cutting than in two side root cutting. The souble protein and free amino acid are decreased in the near root cutting and four side root cutting. As for the Pro, four side root cutting are higher than CK, two side root cutting lower than CK.Nitrate nitrogen are higher than CK in 60cm root cutting, and lower than CK in 80cm and 100cm. Root cutting decreased the ammonium nitrogen and available P. Under the same root cutting distance, two side root cutting have lower nitrater nitrogen and ammonium nitrogen, but have higher available P than in four side root cutting because root secretion have activation on soil P. Root cutting also can increased the activtity of catalase and urease, and decreased the activity of polyphenol oxidase, increased amount of bacterium, actinomycetes, fungus and microorganism, and four side root cutting superior to two side root cutting.Root cutting obviously increased the DHB and tree height. As for volume of timber, the 8-2 treatment is the best, the second were10-2 and 10-4, 6-2、8-4 and 6-4 were in th last. But all root cutting treatment have higher yield than CK. Root cutting also increased the nutrient content of root stem and leaf. Thus it can be concoulded that reasonable root cutting is feasible to increase poplar yield.4. Organic fertilizer: Application of organic fertilizer can increased the leaf SOD activity, decreased the MDA content. It was also incresed the souble protein and souble sugar, decreased free amino acid in later stage, therefore, organic fertilizer can decrease the degree of cell membrane lipids peroxide, increased the cell membrane stability.NPK have no obvious law in different fertilizer treatment. But application of organic fertilizer increased the contents of total C, humic acid and fulvic acid, correspondingly the ratio of humic acid to fulvic acid and the value of E4/E6 was increased. This can be inferred that organic fertilizer can increased the activity of soil humus. Application of organic fertilizer also can increase the activity of catalase, dmylase and urease, and decreased the activity of polyphenol oxidase, increased amount of bacterium, actinomycetes, fungus and microorganism.As for the amount of growth, compared to inorganic fertilizer, the application of organic fertilizer increased DBH, tree height and volume of timber by 40.68%, 38.41%, 35.08% and 33.60% in 1,2,4,3 respectively, CK are the lowest by 28.14%. It is thus clear that the application of organic fertilizer have the significent facilitation on poplar growth.更多还原