共查询到19条相似文献,搜索用时 250 毫秒
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《山东林业科技》2015,(5)
采取光合生理特性分析与光谱特性分析相结合的手段,以建立光合参数、叶绿素含量与反射光谱指数间的相互关系,从而为高效、快捷地监测古树生长状况提供依据。本文以泰山有代表性油松古树姊妹松、一亩松、一品大夫、增幅松为研究对象,测定了当年生针叶的光合特性(净光合速率Pn、蒸腾速率Tr、气孔导度Gs、胞间CO2浓度)、叶绿素含量以及反射光谱特征(植被归一化指数NDVI、叶绿素归一化指数chlNDI、红边位置λre、水分指数WI及植物衰老指数PSRI)。结果表明:随着树势衰弱,叶绿素含量、Pn、Tr、Gs均降低,CI升高,并且呈现出显著差异(P0.05),非气孔限制因素致使油松光合能力降低;油松古树的反射光谱指数chlNDI、λre、WI降低,呈现出与叶绿素含量、Pn相同的变化规律,健壮油松PSRI较小,一亩松、一品大夫等衰弱古树PSRI值较大,NDVI值变化不明显。表明采用光谱分析技术能在古树生长状况监测中发挥作用。 相似文献
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为有效控制雪松(Cedrus deodara)、五针松(Pinus parviflora)、白皮松(Pinus bungeana)等古松树的截口与创伤以及白皮松的树干流胶现象,采用两种不同浓度的林木梳理剂涂刷古雪松、古五针松、古白皮松的截口、创伤处以及古白皮松的树干。结果表明:浓度为50%和80%的林木梳理剂均能有效控制雪松、五针松古树的截口与创伤流胶,两种配比浓度无差异;控制古白皮松的伤口、截口或树干流胶,两种配比浓度有差异,配制浓度为80%的效果优于配制浓度为50%的效果。 相似文献
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松柏类树种为菌根树种,为延缓松柏古树的衰老,对松柏古树进行接种彩色豆马勃、美味牛肝菌和丝膜菌试验。结果表明:接种后古树的生长量、叶绿素含量、根系活力和根系侵染率均有增加,尤其是根系活力增加。白皮松接种彩色豆马勃效果优于丝膜菌,桧柏接种丝膜菌效果最优。接种菌根菌后,能降低土壤的p H值,提高土壤有机质,对土壤中的速效氮、有效磷也起到较好的调节作用。 相似文献
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古树名木是中华民族悠久历史与文化的象征,有着重要的科研价值,当前古树名木面临树龄较高、树势衰老、生理机能下降等问题。随着城市园林绿化事业的发展及市民爱绿护绿意识的增强,对于古树名木保护工作的要求也越来越高。济南千佛山风景名胜区内分布着345株古树名木,其中部分树木长势较弱,景区在研究了树木生长衰弱的原因并借鉴了国内先进的古树名木复壮经验后,对景区内的唐槐实施了复壮措施,复壮的主要内容是树体修补、消除虫害及改善树木生长环境。景区寄希望此次复壮工作能为今后的古树名木保护探保护工作索道路。 相似文献
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文章通过使用Li-6400对移植成活一年、二年、三年后的15a生樟子松大树的光合速率、蒸腾速率、气孔导度、胞间CO2浓度、叶片水势以及叶绿素含量的测定,进行了不同移植成活时间对樟子松大树光合特性影响的研究。结果表明:①蒸腾速率、光合速率、气孔导度以及胞间CO2浓度均先减小后增加;②移植成活二年时,水分利用效率最高;③叶片水势不断下降;④叶绿素含量先降低,后升高,基本维持在的7mg.g-1的水平。由于移植成活二年时最易受到干旱胁迫的影响,所以,有必要在樟子松大树移植后的两年内采取有效的措施促进其成活及树势恢复。 相似文献
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古油松衰弱衰老诊断的生理指标 总被引:1,自引:0,他引:1
选取颐和园不同树龄油松及其衰弱株的一年生针叶为试材,测量不同季节的针叶单位质量的长度、叶绿素含量、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性等指标。结果表明:与健康油松比较,衰弱油松树冠不完整,一年生针叶柔弱细长,针叶单位质量的长度值大;衰弱油松叶绿素含量低、光合能力弱,叶绿素a/b值低,光能利用效率低。在一年的生长季节中,油松MDA含量随针叶的发育逐渐升高;与健康油松比较,衰弱油松针叶MDA含量远高于健康油松,而针叶SOD总活性和SOD比活力均低于健康油松,其抗氧化能力弱。这些结果说明:针叶单位质量的长度、叶绿素含量、MDA含量、SOD活性等可以作为古油松衰弱衰老的诊断指标。 相似文献
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Liu HuirongNortheast Forestry University 《林业研究》1993,4(2):11-17
The plantations of korean pine(Pinus koraensis)and scots pine(Pinus sylvesrisvar.mongolica)are mainly pure stands.Fires are gradually causing problems in theseplantations and being paid much more attention recently.Study on the influence of fire ontrees and the adaptation to fire,therefore,is of great important to probe the fire ecologicalproperties and the protection ways of these two species.The results are as follows:Bothof the species are easily damaged by fire,but korean pine is more susceptible.In the samefire,korean pine is damaged more seriously than scots pine although they have the samesize.Young individuals have low fire resistant capacity and can be damaged seriously,andolder ones have strong fire resistance and can be damaged lightly.Up-hill fire makes aserious damage to the trees distributed in up-slopes with the reason of higher fireintensity.Down-hill fire makes a serious damage to the trees distributed in down-slopcswith the reason of higher fire severity.The larger deocambium area in t 相似文献
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长白山林区次生阔叶林冠下红松人工更新与培育技术 总被引:2,自引:0,他引:2
通过对长白山林区林隙环境、林隙对红松生长的影响及肛伐强度对阔叶树生长、红松更新的研究,为科学地确定上红松更佳的最佳上层郁闭度,提高林分生长量,确定红松采伐年龄,促进天然林保护工程的发展提供科学的依据和技术。 相似文献
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本文就中条山油松株内幼龄材与成熟材材性差异的比较研究,讨论对幼龄期划分的依据。根据木材解剖特征、物理力学性质的径向变异规律,确定其幼龄期为14年。随着树干高度的增加,油松木材幼龄期逐渐缩短、株内幼龄材范围及所占断面上的比例变小。株内幼龄材与成熟材材性差异显著。幼龄材管胞长度短、直径小,胞壁薄,微纤丝角度大,生长轮较宽,晚材率低,浸提物含量高,基本密度较大。幼龄材的力学强度远远小于成熟材。 相似文献
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《Journal of Sustainable Forestry》2013,32(3):21-35
Abstract Acute (broken and leaning) and transient (bending) damage to loblolly pine (Pinus taedaL.) were assessed in a case study of experimental agroforestry plantations following a December 2000 ice storm. Stand ages were 7-, 9-, and 17-years-old and tree density ranged from 150 to 3,360 trees ha?1 in rectangular and multi-row configurations. Wider tree spacing or lower stand density of 7-year-old trees increased stem breakage, while closer spacing increased bending. There was substantial straightening of bent 7-year-old trees 8 months after the storm, and this recovery was determined more by degree of initial bend rather than height or diameter. Nine-year-old loblolly pine had 19% more top breakage and 59% more stem breakage than shortleaf pine (P. echinataMill.) (P < 0.001). Agroforestry design influenced ice damage in 7-year-old stands, but no design had catastrophic loss. Thinning from above caused an increased susceptibility of ice damage to a 17-year-old stand compared to a nonthinned stand. The case study supports the cultivation of loblolly pine in areas prone to ice damage. 相似文献
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Roger F. Walker Robert M. Fecko Wesley B. Frederick Watkins W. Miller Dale W. Johnson 《Journal of Sustainable Forestry》2013,32(6):469-492
Variability of postfire injury and stand and individual tree factors that affected survival responses of eastern Sierra Nevada conifers to wildfire were examined. Prefire measurements served as a basis of comparison for postfire conditions in a mixed conifer stand located in the eastern portion of the Lake Tahoe Basin and provided insight into predisposing influences on survival. Species composition consisted primarily of Jeffrey pine (Pinus jeffreyi Grev. & Balf.) and California white fir (Abies concolor var. lowiana [Gord.] Lemm.) along with a minor component of sugar pine (Pinus lambertiana Dougl.). Postfire survival was higher in Jeffrey pine than white fir but was highest overall in sugar pine. Catastrophic crown loss occurred less frequently in Jeffrey pine than in the fir but was least common in sugar pine. Survival generally increased with tree size, but this relationship did not extend to the largest trees in the stand. Among an array of regression models used to evaluate selected variables for their predictive capacity regarding postfire survival, prefire stand density was found to negatively influence that of Jeffrey and sugar pine, and survival of Jeffrey pine and white fir was negatively correlated with bole char. These results provide natural resource managers guidance in the selection of viable trees for retention during the salvage harvesting operations that often follow wildfire events. 相似文献