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冀北干旱山地乔砧苹果密早丰栽培经验王泳力,刘润福,何玉香(承德市林业局067000)冀北地区多为山地,土壤瘠薄,灌溉条件差,气候寒冷,风沙大,十年九旱。为提高苹果抗性,当地群众习惯于用山丁子、海棠等乔砧嫁接繁殖苹果进行栽培,随之而来的是一些土肥水条件... 相似文献
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通过对北宁市山地刺槐人工林立地条件、生长规律及生态效益等调查,结果表明,在类似北宁生态条件的半干旱地区的山地,适宜于培养小径级刺槐人工林;造林地要选择在阳坡、半阳坡、山中下腹土层较厚的地块;造林前需要整地;这些地区营造刺槐人工林,有助于保持水土,改良土壤,促进造林地植被变化,恢复和改善生态环境,减少病虫危害。 相似文献
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指出了干旱、半干旱山区山地是我国生态建设中较难克服的一部分.以云南省为例 ,主要对云南省干旱、半干旱山区山地的造林情况进行了分析.结果表明:云南省的山区山地以喀斯特地貌(溶岩地貌)为主 ,是我国分布最广的地区.云南省由于其人口压力和经济落后等原因 ,造成了生态环境的破坏 ,因此 ,干旱、半干旱地区的造林成为云南省生态建设的重要的目标. 相似文献
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本文评价了四川茂县大沟地区海拔1800~2000m的区段10个供试树种的成活率、生长量和适应性。结果表明:在设定的具体生境条件下,供试树种的成活率受到自身遗传、生态习性及其自然环境与人类活动干扰的影响,通过对高生长量的测试确定了上述树种的生长量差异序列,并进一步结合对抗逆性的现场调查确定青榨槭、光皮桦、臭椿、天师栗很适应当地的环境,可以作为当地植被恢复的材料使用;腺果杜鹃、山桃、枫香、野核桃适宜当地环境,但尚需作进一步研究观察,以便确定使用方案;而银杏与珙桐不能作为营林材料利用。 相似文献
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山地大果杨梅良种栽培经济效益分析 总被引:1,自引:0,他引:1
采用技术经济分析方法,研究了山地大果杨梅良种栽培的成本构成和各项经济指标。结果表明:在15a一个生产周期中,其内部收益率为29.72%,投资回收期7.40a,每公顷财务净现值253363元,设计产量或价格收益率的盈亏平衡点为57.98%。按标准贴现率5%计算栽培良种和一般品种的动态经济指标,结果表明:在15a—个生产周期中,栽培良种比一般品种每公顷产值增加244574元,税后利润增加160979元,内部收益率高出10.02个百分点,多交税收80595元,投资回收期提早1.19a。在影响杨梅良种栽培经济效果的诸因素中,以销售收入变动影响最大,其次为生产成本,但从近期市场情况来看,投资回收期相对较长,其自然风险、市场风险和政策风险都比较小。从长期来看,盲目大规模发展大果杨梅生产存在一定市场风险,因此,在生产上应注意推行适度规模经营。 相似文献
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为探讨北海道9号苹果在冀北山地推广的可能性,于1995 ̄1997年进行了引种观察,积累了试验数据。结果表明,北海道9号苹果抗寒性较强,丰产性能好,果实着色好,品质优良,可在冀北平泉县中部及其以南的区域进一步进行生产示范,建园方式采用以国光/海棠作基砧,用高接换头方法较好。 相似文献
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Growth performance of some multipurpose trees and shrubs in the semi-arid areas of Southern Ethiopia
Tesfaye Abebe 《Agroforestry Systems》1994,26(3):237-248
Growth performances of some multipurpose trees and shrubs have been studied for five years at two locations in the semi-arid areas of Southern Ethiopia. The best performance in terms of rates of survival and growth rates (height and diameter growth) has been attained byAcacia nilotica, A. Cyanophylla, A. seyal, Cassia siamea andProsopis juliflora. Given the ecological limitations of semi-arid areas, growth rates of these species is promising and this indicates that sustainable production system can be realized using proper agroforestry technologies in the semi-arid areas of Southern Ethiopia and similar area types elsewhere. 相似文献
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1特征特性 苹果 (Malus pumila)属于蔷薇科、苹果属的落叶小乔木,幼枝、叶片和冬芽均长有柔毛,叶为卵形或椭圆形,先端尖,边缘具钝锯齿状。伞房花序,有花 3~ 7朵,花呈淡红色或淡紫红色,边缘色泽较深,大多数品种自花不孕,需种植授粉品种,果实有子房和花托两部分发育而成,子房形成果心,花托形成果肉。因品种而言,果实呈圆、扁圆、长圆、椭圆形等,果皮有青、黄、红色等。果期 8~ 11月份,是集花果并美的优良观赏树种之一。 苹果为温带树种,在我国东北南部、华北、西北等地广泛栽培,耐寒、不耐湿热,寿命较长。 3~ 5… 相似文献
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Pull-down tests were conducted for apple trees grafted in an orchard and for support posts in order to discuss the failure
mode in windthrow damage, the effect of rootstock types on the uprooting strength, and the reinforcing effect of support posts
on young trees. The test samples were ten mature trees (20–23 years old) of three varieties grafted on two types of rootstocks,
three young trees (7 years old) grafted on dwarf rootstocks, and nine support posts of larch logs and steel pipes. The failure
modes were found to be uprooting for mature trees and rootstock breakage for young trees. The uprooting strength of apple
trees was considerably smaller than the uprooting strength of forest trees reported in previous studies. However, the windthrow
resistance of the apple trees with respect to the critical wind velocity was estimated to be sufficient despite their low
uprooting strength because of their small height. Young trees should be supported with wooden posts for a few years after
grafting so that they acquire sufficient windthrow resistance.
Part of this study was published in the report for the Grant-in-Aid for Collaborative Research by NOASTEC (No. H17-kyo-048) 相似文献
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A study was conducted in the semi-arid regions of Haryana, in Northern India, to see the effect of Azadirachta indica, Prosopis cineraria, Dalbergia sissoo and Acacia nilotica on the yield of irrigated wheat crop. Data on crop yield for each tree species at different distances (1, 3, 5 and 7 m) and four directions (east, west, north and south) from the tree bases and control (no trees) were collected. Results indicate that A. indica and P. cineraria did not show any significant difference in the wheat yield while the other two species (D. sissoo and A. nilotica) showed a reduction in wheat yield. A. nilotica had the most significant and prominent effect, and a reduction of nearly 40 to 60% wheat yield was observed. The effect of this tree species was observed even beyond the spread of the crown. D. sissoo reduced yield by 4 to 30% but the reduction was only up to a distance of 3 m. In general, the impact of trees on wheat yield was observed up to 3 m distance and there is little, if any, impact up to 5 m distance and almost no impact at 7 m distance. In all the tree species, the wheat yield was reduced to a maximum on the north side of the trees and had almost no effect in the southern direction. Crop maturity was observed to be delayed by three weeks under A. nilotica, by 9–10 days under D. sissoo, and only by 6–7 days under P. cineraria and A. indica. 相似文献
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为了指导河北省滦平县的苹果栽植,以3a生国光苹果苗木为试材,研究了不同栽植时期苗木的成活率及生长情况,结果表明,4月8日栽植的苗木成活率、下部小主枝上的长梢数分别为92.67%、9.26个,极显著高于4月15日和4月22日栽植的处理;新梢平均长度为39.93cm,显著高于4月15日和4月22日栽植的处理;单株长梢数13.73个,显著高于4月22日栽植的处理。4月15日栽植的苗木成活率、下部小主枝萌芽率、下部小主枝上的长梢数分别为75.67%、39.71%、7.58个,极显著高于4月22日栽植的处理;单株中梢数为14.95个,显著高于4月22日栽植的处理。3个栽植时期的地径、单株短梢数和叶丛枝数无显著差异。表明4月8日栽植苹果苗木的生长情况优于后面的2个时期,在滦平县4月份内栽植苹果苗木应越早越好。 相似文献