共查询到18条相似文献,搜索用时 187 毫秒
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在河南省民权林场进行窄冠刺槐带干苗和截干苗造林试验和截干苗造林后幼林不同树体管理方法试验,结果表明:(1)北方地区培育窄冠刺槐速生丰产林,宜采用截干苗造林,截干苗造林成活率比带干苗的高9.26%,造林当年、第2年和第3年的树高分别增加13.6%、11.1%和11.4%,且差异均极显著(P0.01),胸径生长无显著差异(P0.05);(2)带干苗造林会发生死干现象,死干率高达52.30%,极大影响干形;(3)截干苗造林当年采取任何树体管理措施包括定株、抹芽及短截竞争枝都会降低窄冠刺槐造林当年的的胸径和树高生长量,生长量表现为不定株、不抹芽定株、不抹芽定株、抹芽,这种对生长的负面影响在造林后第3年会减弱或消除;(4)截干造林当年不采取任何树体管理措施,于当年冬季或第2年初春树液流动前进行去萌留主干并去除顶端竞争枝,可获得最大的胸径和树高生长量并可以保持良好干形。 相似文献
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荒漠草原地带牧防林营造技术研究初报 总被引:1,自引:0,他引:1
荒漠草原干旱缺水,提高造林成活率是关系牧防林形成和发展的关键。为了探索牧防林营造技术,从种苗、季节和造林技术措施几方面进行了探索,得出荒漠草原地带造林采用容器苗、1年生苗,秋季造林,同时采用座水造林、高分子吸水剂蘸根、4年生大苗造林后截干等措施是造林取得成功的方法。 相似文献
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山区提高造林成活率的八项措施在近几年的春季造林实践中,采用以下措施来提高成活率,收到了明显效果。1容器苗造林容器苗带土坨,根系完整,不易受损,造林后易成活。2截干栽植截干可减少苗木水分的蒸发,有利于成活。一般留茬高度为3~5cm。3根部浸水或蘸泥浆栽... 相似文献
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朝阳地区气候干旱 ,栽植大枣根蘖苗 ,用老式造林技术方法栽植 ,不易成活 ,采取插瓶法和截干覆膜套袋等技术措施获得了较高的造林成活率 ,从而充实了栽植大枣根蘖苗造林技术最新内容 相似文献
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采用4个水平追施氮肥进行杨树截干造林试验,结果表明:追施氮肥能够促进杨树截干苗生长,各处理水平与对照相比,差异显著,以50g·株~(-1)施用量效果最好,苗高达2.87m,地径达2.96cm。 相似文献
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意杨在我镇试种到推广已有4年。从引进苗木,到自己培育意杨苗和截根插干栽种的反复实践,我们认为采用意杨截根插干栽种技术,可以降低起苗、运输、挖穴、栽植成本,减轻劳动强度,提高造林成活率,加速林木速生丰产,提高经济效益。根据我镇截根插干栽种的成功经验,要提高成活率,必须抓牢以下技术环节。 一、截根、选苗 截根。从意杨苗圃地截取造林用的苗干,一般在意杨苗大量落叶至萌芽前进行,但宜早不宜迟。这样既可以解决春季绿化季节劳力紧张的矛盾,又有利留根苗圃的冬季管理和翌年萌蘖苗的早发。截取苗干时用手锯或锋利… 相似文献
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In order to identify the optimum cutting density for producing the highest number of plantable seedlings of poplar clones,
a split-plot randomized block design was used to establish four cutting densities in plots. Based on data on the survival,
leaf area, seedling height, caliper, and biomass of 1-year-old seedlings of clones Nanlin-95, Nanlin-895, Nanlin-1388 and
NL-80351, the growth characteristics and seedling quality under four cutting densities were analyzed. Results indicated that
the leaf area, stem and leaf biomass, and caliper of seedlings of all four poplar clones increased with the decrease in cutting
density. Leaf area index reached its highest level at the spacing of 40 cm×40 cm, while the aboveground biomass of the seedling
on an area basis increased as the cutting density increased. Seedling quality at low cutting density was higher than that
at closer cutting density. The quantity of first-grade seedlings (grade I) for clones Nanlin-95 and Nanlin-895 was achieved
at the spacing of 40 cm×50 cm; for NL-1388 and NL-80351, it was 50 cm×50 cm. According to the seedling quality and the number
of plantable seedlings produced, the suggested cutting density for these four poplar clones was 50,000 stems/hm2. 相似文献
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杨树湘林新无性系不同部位育苗生长性状研究 总被引:1,自引:0,他引:1
新、老杨树无性系田间扦插育苗成活率,在湘林~90等5个新无性系与对照中汉-17杨之间有极显著差异,以中汉-17最低;5个杨树湘林新无性系间均无显著差异,可满足大田扦插育苗要求。成活率在苗干区分段问总体上随所取穗条部住的升高而有所下降;但第2、3、4区分段间无显著差异,表明杨树种苗上部的有芽茎干可以用作育苗种条。在夏季无抗旱措施情况下,年末保存率比春季成活率平均有所下降。大田育苗的保存率、成活率与水培时的皮层凸起呈正相关,反映先期根原基多、水培时易形成皮层凸起的无性系及区分段,可以期望有较高的育苗成活率和保存率。成活率、保存率与水培时的发根总长,苗高生长量与水培时的皮层凸起、不定根条数、总长间均没有相关性。试验显示,杨树新无性系扦插繁殖能力的鉴定,最重要、最可靠的程序是通过大田育苗的生产实践来检验。 相似文献
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通过三尖杉播种、扦插育苗试验,研究不同种源种子、不同穗条及不同生根剂处理对三尖杉苗木繁殖的影响,结果表明:福建柘荣和安徽黄山种源的种子相似,与云南易门种源的种子相比,种子外形较大,发芽率高,实生苗生长较快。穗条采用ABT1250 mg.L-1+双吉尔250 mg.L-1浸泡10 h,扦插生根率最高;幼龄母树比老龄母树、顶梢比不带顶梢、萌条比树冠上的穂条的扦插成活率高;三尖杉扦插苗木偏冠现象明显,偏冠现象同穗条采条的位置、穗条年龄有关,幼龄母树萌条带顶梢穗条的扦插苗偏冠率最低,老龄母树不带顶梢穗条的扦插苗偏冠率最高。 相似文献
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A field experiment was established in the autumn of 1992 in order to study predation of acorns, germination and early growth of oak seedlings. The experiment was established on a clearcut and an adjacent oak shelterwood in southern Sweden. In the experiment, a total of 6 840 acorns were sown. The sowing was carried out with different vegetation control and soil preparation treatments and with different planting depths.The germination percentage was highest for acorns sown at five cm depth and lowest for acorns sown on top of the soil, and lower for acorns sown in areas where the humus layer had been removed than in areas where the humus layer was retained. There was no difference in the percentage germination after two growing seasons between acorns sown inside the shelterwood and acorns sown on the clearcut. The height of the seedlings was lowest when the humus was removed while the number of leaves per seedling was lowest for seedlings in untreated areas after two growing seasons. Furthermore, seedlings in untreated areas showed the lowest relative height growth rate during the second growing season. In spite of higher biomass of ground vegetation in undisturbed areas compared to treated areas, no effect of the soil and vegetation control treatments could be found on soil water potentials. The soil temperature and photosynthetic active radiation at seedling level were higher in areas where soil preparation and vegetation control had been performed. However, it was concluded that neither low soil water availability nor low light levels could be the only cause of lower relative height growth rate during the second growing season for seedlings in undisturbed areas. 相似文献