【作者】 井大炜；

【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， 2013， 博士

【摘要】 目前，我国的杨树人工林栽培面积已居世界首位。欧美I-107杨(Populus×euramericana cv.‘Neva’)因其具有优质、速生和丰产等特点，在山东省内大面积种植，然而在实际生产中，普遍存在缺乏科学有效的管理措施的问题，在一定程度上造成了林地土壤生态环境退化、林地生产力下降的现象。针对以上问题，本论文对欧美I-107杨从配施有机肥、根系修剪、节水灌溉和地膜覆盖等多项高产栽培关键技术方面进行了系统深入的研究，主要研究结论如下：1.配施鸡粪：同N100（单施化肥）相比，M30N70（鸡粪与化肥分别提供30%和70%的氮）显著提高了根际土壤酶活性及微生物量碳、氮含量。随着鸡粪所占比例的增加，根际土壤有机碳含量呈递增的趋势，而活性有机碳含量呈先升高后降低的趋势。M30N70处理还显著降低了根际土壤pH，提高了土壤速效养分、胡敏酸碳含量和胡/富比。配施鸡粪有利于杨树苗根系的生长，并能显著提高根系活力、总吸收面积和活跃吸收面积。此外，M30N70处理的根系总根长、表面积、体积和根尖数明显高于其它处理，且氮素利用率最高，达到了61.38%。综合来看，在鸡粪与化肥不同比例中，以3:7比例配施对杨树苗的作用效果最佳。2.根系修剪：采用不同的根剪方法对三年生、四年生和五年生杨树生长的影响进行了研究，结果表明：8-2（八倍胸径两侧）根剪处理对胸径生长率、树高生长率及材积生长率的提高幅度最大；其次是10-2（十倍胸径两侧）或10-4（十倍胸径四侧）处理；而6-2（六倍胸径两侧）和6-4（六倍胸径四侧）处理均显著低于对照，尤其是6-4处理。采用8-2根剪方法，研究了连续根剪和隔年根剪方式对杨树根际土壤特性及生长的影响，结果表明：各根剪措施均显著提高了杨树的根系活力和根系分泌物含量，并使根系中生长素、赤霉素和玉米素的含量也得到明显提高，而脱落酸含量显著降低。各根剪处理明显增加了根际土壤微生物数量，显著提高了根际土壤的酶活性，且对杨树生长均有一定的促进作用。在各种根剪措施中，T35(对三年生杨树在第三年、第五年根剪)处理对杨树根际生态环境的改善效果及生长的促进作用最为明显。3.节水灌溉：同常规漫灌相比，畦灌能明显减弱水分的深层渗漏；随着土层深度的增加，畦灌和漫灌下的根系生物量均逐层降低，大量根系集中在0~40cm土层，其中在0~20cm土层中，畦灌的根量比漫灌减少8.28%，但在20~80cm土层中根量却增加35.87%，并且在0~80cm土层中的总根重增加5.52%；畦灌使0~40cm土层的硝态氮含量显著升高，而60~100cm土层的硝态氮含量明显降低，其中在80~100cm土层中，灌溉后7d、14d和29d，畦灌的硝态氮含量分别比漫灌减少21.84%、20.24%和19.53%。此外，畦灌对杨树胸径、树高和材积生长率的促进作用与漫灌相当。4.地膜覆盖：在两种不同覆膜方式中，白膜覆盖的增温效果优于黑膜覆盖，而对土壤含水量的影响差异不显著。在0-20cm土层中，白膜和黑膜覆盖均显著提高了土壤总孔隙度、毛管孔隙度和非毛管孔隙度，而土壤容重明显降低；覆膜还显著增加了土壤碱解氮含量、微生物量碳和活跃微生物量，明显提高了过氧化氢酶、蔗糖酶和多酚氧化酶活性，但却明显降低了pH和有机质、全氮、速效磷含量以及脲酶活性。随着土层的加深，覆膜对土壤理化性状及生物学特征的影响越来越小。此外，两种覆膜方式均能明显提高杨树的胸径、树高和材积生长率，其中，白膜覆盖的胸径、树高和材积生长率分别比黑膜覆盖提高10.95%、9.26%和8.77%，差异均达显著水平。可见，白膜覆盖和黑膜覆盖均能明显改善土壤理化性质，促进杨树生长，但白膜覆盖的作用效果明显好于黑膜覆盖。更多还原

【Abstract】 At present, Chinese poplar cultivation area is the largest in the world. Owing to thecharacteristics of high-quality, fast-growing and high yield, the poplar(Populus×euramericana cv.‘Neva’) has been planted largely in Shandong province. However,there is such problem of lacking scientific and effective management measures in practicalproduction, which results in the degradation of forest soil and the decrease of forestproductivity. To solve the problem as above, system research on poplar was carried outincluding key techniques of co-applied with manure, root pruning, irrigation and plastic filmmulching. The main results were as follows:1. Co-applied with chicken manure: In comparison to the N100treatment (100%ofnitrogen was provided by urea), the M30N70treatment (30%and70%of nitrogen wasprovided by chicken manure and urea, respectively) could significantly increase soil enzymeactivity, microbial biomass C and microbial biomass N contents. With the increase in theproportion of chicken manure, the total organic carbon content in rhizosphere soil increasedconsistently, while the active organic carbon content had a trend of first up then down. TheM30N70treatment also obviously decreased the pH value, enhanced the contents of availablenutrients and humic acid carbon, as well as the ratio of humic acid to fulvic acid. Co-appliedwith chicken manure was beneficial to root growth, which evidently improved the rootactivity, total absorption area and active absorption area. In addition, the total length, surfacearea, volume and tips number of root system in M30N70treatment were distinctly higher thanthe other treatment, and the nitrogen use efficiency was61.38%, achieving the maximumamong all the treatments. As a result, chicken manure co-applied with inorganic fertilizer,especially the M30N70treatment, had the best effect on poplar seedlings.2. Root pruning: The study was conducted to determine the effects of different rootpruning methods on three-year-old, four-year-old and five-year-old poplar. The results showed that the8-2treatment (eight times of DBH and two sides) significantly improved the growthrates of DBH, height and volume, with the maximal increase. The second was either10-2(tentimes of DBH and two sides) or10-4(ten times of DBH and four sides) treatment. But the6-2(six times of DBH and two sides) and6-4(six times of DBH and four sides) were obviouslyreduced compared to the CK treatment, especially the6-4treatment.With8-2root pruning method, the study was carried out to determine the effects ofcontinuous and intermittent root pruning on rhizosphere soil characteristics and growth ofpoplar. The results indicated that all root pruning treatment could significantly enhance notonly the root activity and the root exudates content, but also the contents of IAA, GA and ZTin root system, however, the ABA content was obviously decreased. Every root pruningtreatment also significantly increased the microbial population and enzyme activities in therhizosphere soil. What is more, they had evident promotion effects on poplar growth. Indifferent root pruning treatments, the T35treatment (root pruning on three-year-old poplar inthe third and fifth years) played the most significant role in improving the ecologicalenvironment and growth of poplar.3. Water-saving irrigation: The BI treatment (border irrigation) significantly weakenedthe water deep seepage in comparison with the FI treatment (flooding irrigation). With theincrease of soil depth, the root biomass decreased layer by layer and most of the rootsconcentrated in the0-40cm soil layer. Compared to the FI treatment, BI treatment couldreduce the root biomass by8.28%in the0-20cm soil layer, while increase by35.87%in the20-80cm soil layer, furthermore, the total root biomass increased by5.52%in0-80cm soillayer. At the same time, the nitrate nitrogen content increased markedly in0-40cm soil layer,but reduced significantly in60-100cm soil layer. In the80-100cm soil layer, the nitratenitrogen content was decreased by21.84%,20.24%and19.53%at7days,14days and29days after irrigation, respectively. Additionally, the BI treatment had the same promotioneffect as the FI treatment on the poplar growth rates of DBH, height and volume.4. Plastic film mulching: The WM treatment (white plastic mulching) had the betterwarming effect than the BM treatment (black plastic mulching), while had no significantdifference on soil water content. In the0-20cm layer, the WM and BM treatmentssignificantly increased the soil total porosity, capillary porosity and non-capillary porosity, however, the soil bulk density was visibly decreased. Plastic film mulching could significantlyincrease the contents of alkaline hydrolysis N, microbial biomass C and active microbialbiomass. The activity of catalase enzyme, invertase enzyme and polyphonic oxidase enzymewas also obviously improved, but the pH value, the contents of organic matter, total nitrogenand available P, as well as the urease enzyme activity were significantly decreased. With theincrease of soil depth, the effects of plastic film mulching on soil physio-chemical propertiesand biological characteristics become smaller and smaller. Besides, two plastic film mulchingmethods could significantly improve the poplar growth rates of DBH, height and volume.Moreover, the WM treatment could significantly increase the growth rates of DBH, height andvolume by10.95%,9.26%and8.77%compared with the BM treatment, respectively. Inconclusion, two different plastic film mulching treatments significantly ameliorated the soilphsio-chemical properties and improved the growth of poplar; however, the WM treatmentwas obviously better than the BM treatment.更多还原