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1.
基于树木年轮学方法,在哈巴雪山海拔上、下限采集高山松年轮样本,建立差值年表并分析其与气候因子关系,以揭示影响该区域高山松(Pinus densata)径向生长的主要气候因子。结果表明:海拔上限高山松径向生长主要受上年8月水热状况影响,还与当年3月平均最高温呈显著正相关、与5月平均温和6月降水均呈显著负相关;海拔下限高山松径向生长主要受当年5月水热状况影响,还与上年12月降水呈显著正相关;哈巴雪山高山松径向生长与气候因子关系较为稳定。通过对横断山区树轮研究的补充,可为未来气候变化下森林保护提供理论依据。  相似文献   

2.
以马尾松为研究对象,在南岭地区不同纬度(26°33′N,北部;25°47′N,中部;24°42′N,南部)分别设立样地,用生长锥法在树高1.3 m处钻取木芯,经晾干、打磨后,使用Lin Tab5型年轮测量分析系统进行轮宽测量,利用COFECHA程序对年轮宽度序列进行交叉定年,运用ARSTAN程序建立了树轮宽度年表;利用相关分析统计方法,对年轮宽度与气候因子的相关性进行研究。结果表明:北部地区马尾松径向生长主要受冬季和夏季温度的影响,冬季和夏季温度的升高均促进了马尾松的径向生长;中部地区马尾松的径向生长主要受冬季和夏季温度的影响,冬季温度的升高促进了马尾松的径向生长,但夏季温度的升高在一定程度上抑制了马尾松的径向生长;南部地区马尾松的径向生长主要受夏季温度的影响,夏季温度的升高抑制了马尾松的生长。降水对马尾松径向生长的影响只与南部地区显著相关,中部地区马尾松的径向生长与上年10月的降水相关,但不显著。  相似文献   

3.
三峡库区秭归县不同海拔马尾松径向生长对气候的响应   总被引:7,自引:0,他引:7  
利用采自三峡库区秭归县不同海拔高度的马尾松树轮样芯,分别建立树木年轮宽度年表.包括标准年表和差值年表,并对2种年表进行比较.运用相关函数及单年分析等树木年轮学方法,研究秭归县马尾松在不同海拔高度处的径向生长与气候变化的关系.最后通过多元回归得出不同海拔高度处马尾松年轮指数与气候因子的关系模型.结果表明:在正常的气候条件下,海拔300 m处马尾松生长受上年6和10月份降雨量和湿润指数的影响,与当年气候因子的关系不显著;海拔600 m处马尾松生长与上年6月份温度呈显著相关,还受当年7月份的月平均降雨量和湿润指数的影响;海拔900 m处马尾松生长不仅与当年2月份温度呈显著相关,还受当年12月份月平均降雨量和湿润指数的影响,单年分析进一步印证了这种关系.  相似文献   

4.
马尾松宏观尺度单木生长模型研究   总被引:2,自引:0,他引:2  
《林业资源管理》2017,(2):28-33
林木生长模型是预测森林未来发展、评估生产潜力的定量依据。以我国南方主要针叶树种马尾松(Pinus massoniana)为对象,利用在马尾松分布范围内收集的代表性样本,建立全国尺度的胸径和树高单木生长模型,并分析生长模型是否受地域和起源的影响。结果表明:马尾松胸径的生长过程仅与地域有关而与起源无关,而树高的生长过程则受到地域和起源的双重影响;所建胸径和树高总体平均生长模型,确定系数分别为0.79和0.71,平均预估精度均在96%以上;包含地域和起源因子的胸径和树高生长模型,比总体平均模型有显著改进,其确定系数分别达到0.83和0.74,平均预估精度均进一步提高。所建生长模型为在宏观尺度上预测马尾松林的蓄积量、生物量和碳储量提供了定量参考依据。  相似文献   

5.
马尾松阔叶树混交林生长、生物量及土壤养分特征   总被引:2,自引:0,他引:2  
研究了10年生马尾松+马褂木、马尾松+光皮桦和马尾松+乳源木莲混交林生长、生物量及土壤养分特征.结果表明:马尾松+马褂木、马尾松+光皮桦和马尾松+乳源木莲总蓄积量分别比马尾松纯林增加了103.6%、51.5%和1.5%,总生物量分别比纯林增加了122.0%、39.7%和5.0%.马尾松混交林与纯林生物量空间分布模式类似,均为干>根>枝>叶.马尾松混交林的营建有效改善了土壤肥力状况,其中马尾松+马褂木效果最佳,尤其是显著提高了土壤有机质、土壤全磷和有效磷含量.  相似文献   

6.
采用4种珍贵阔叶树与马尾松进行混交造林试验,结果表明:4种针阔混交林中,不同珍贵阔叶树的平均胸径、平均树高、高径比及林分蓄积量存在极显著差异,林分生长表现为枫香香樟闽楠红楠。不同珍贵阔叶树对马尾松生长有不同影响,马尾松林分蓄积量存在极显著差异,马尾松×闽楠混交林中的马尾松林分蓄积量最大,其余依次为马尾松×红楠、马尾松×香樟、马尾松×枫香。不同混交模式的林分总蓄积量从高到低依次为马尾松×闽楠马尾松×枫香马尾松×红楠马尾松×香樟,但其差异不显著。  相似文献   

7.
马尾松木荷混交林林分结构和土壤肥力研究   总被引:10,自引:0,他引:10  
对马尾松木荷混交林与马尾松纯林林分生长、径阶分布及土壤理化性质研究表明 :马尾松与木荷以 2∶1比例行状混交 ,马尾松生长快 ,林分各径阶呈正态分布 ,林分生产力高、结构稳定。马尾松木荷混交林不仅提高土壤通透性和蓄水性 ,促进土壤良好结构形成 ,而且增加土壤养分含量 ,改善土壤肥力状况  相似文献   

8.
松材线虫病是松树的一种毁灭性病害,不同种源的马尾松的抗病性存在差异.就马尾松对松材线虫病的抗病性差异研究进展进行了综述.目前,马尾松抗病性的研究主要有以下5个方面:①不同树龄与抗病性之间的关系;②不同地理种源马尾松对松材线虫病抗病性的差异;③与种源抗病性有关的主要成分;④马尾松的诱导抗病性;⑤马尾松抗病育种.马尾松的抗病性与多种因素有关系,通常具有抗性的马尾松一般生长状况较好;马尾松的抗病物质很复杂,到目前为止,人们已经发现了马尾松的一些抗病物质的种类,并对这些物质的结构进行了研究,但对这些抗性物质的产生和马尾松抗病机理还有待于进一步的研究.  相似文献   

9.
马尾松混交林生长及生态效应研究   总被引:1,自引:0,他引:1  
通过马尾松杜英混交林、马尾松闽粤栲混交林和马尾松纯林生长状况、林分植被生物多样性和土壤理化性质的研究,结果表明,马尾松与杜英、闽粤栲混交后,树高、胸径生长量增加明显,蓄积量增大;马尾松混交林下植被种类和数量都增多,生物多样性比马尾松纯林丰富;马尾松混交林土壤理化性质得到较大改善。  相似文献   

10.
造林密度对马尾松木材主要性质影响的研究   总被引:1,自引:0,他引:1  
夏玉芳  谌红辉 《林业科学》2002,38(2):113-118
本文对贵州省龙里林场马尾松密度试验林 ,5种造林密度 ,15年生马尾松木材基本密度、生长轮宽度、晚材率和解剖特性进行研究。结果表明 :造林密度对马尾松生长轮宽度、晚材率和管胞列数影响较大 ,方差分析达到显著水平。造林密度大 ,则生长轮变窄 ,管胞列数减少 ,晚材率增加。造林密度对马尾松木材基本密度的影响不显著 ,但具明显的规律性 ,即随着造林密度加大木材基本密度增加 ,造林密度过大反而下降。造林密度对管胞形态的影响表现出因树龄而异 ,不同造林密度马尾松管胞形态总平均值变化不大 ,但管胞长度随树龄的增大而增加的趋势受到造林密度影响。较低的造林密度各生长轮管胞长度差异不显著。组织比量不受造林密度影响。  相似文献   

11.
采用树木年代学的方法,按照珙桐的分布特点分海拔下限(1400 m~1500 m),中部(1 600 m~1 700 m),上限(1 800 m~1 900 m),研究不同海拔梯度下北川珙桐种群的年龄结构,结果表明:海拔上限珙桐年龄结构偏大,缺乏幼苗及30 a~40a的个体;在海拔中部,30 a~40 a的个体占的比例较大,争夺空间和资源的能力更强;海拔下限的实生幼苗较多.在中部海拔分布的珙桐较多,且年龄结构集中在30 a~40 a之间,低海拔的种群特征是以幼苗为优势,而高海拔面有的幼苗却很少,表明海拔对珙桐种群年龄结构有重要的影响.  相似文献   

12.
We analyzed the influence of climate change over the past 50 years on the radial growth of two tree species: Korean pine (Pinus koraiensis) and Yezo spruce (Picea jezoensis), located on Changbai Mountain, Northeast China, using a dendrochronology approach to understand factors that limit the altitude for tree species. Elevated temperatures increased the radial growth of Korean pine and decreased that of Yezo spruce. The positive response of tree growth to hydrothermal conditions was the key reason that the upper limit of elevation of Korean pine followed the temperature fluctuation pattern. Increased temperatures and precipitation and longer growing seasons accelerated Korean pine growth. As the temperature increased, correlations between Korean pine ring-width chronology and precipitation changed from negative to positive. In Yezo spruce, increasing monthly temperatures and inadequate precipitation during the middle and late parts of the growing season led to narrow growth rings, whereas decreasing monthly temperatures and sufficient precipitation during the late growing season promoted growth. Rising temperatures and adequate precipitation increases Korean pine growth, possibly elevating the upper range limit in altitude for this species. In contrast, Yezo spruce growth is negatively affected by warming temperatures and limited precipitation. Under future temperature increases and precipitation fluctuations, the upper limit altitude of Korean pine can reasonably be expected to shift upward and Yezo spruce downward.  相似文献   

13.
《林业研究》2020,31(4)
Assisted migration has been proposed as a strategy for adaptive management of forest species in response to expected effects of climate change,but it is controversial for several reasons.Tropical dry forests are among the most threatened ecosystems in the world.In Mexico,historically,land-use change and deforestation have been decreasing forest cover,and climate change is shifting the potential distribution of different forest types,exacerbating the risk of local extinctions.Assisted altitudinal migration could be a feasible strategy for reducing local extinctions in response to climate change and lack of landscape connectivity.Our objective was to evaluate survival and growth of Albizia plurijuga and Ceiba aesculifolia,two tropical deciduous forests species in Mexico.We transplanted 4-month-old seedlings to experimental raised beds at three altitudes(2100,2400 and 2700 m a.s.l.),exceeding their upper regional limit of distribution(2000 m a.s.l.).We also tested seed germination at each altitude.We monitored the experiment for 10 months.For both species,as altitude increased and cold weather was more prevalent,plant performance declined.Within species,differences in individual growth were significant among altitudes.Overall survival was 18.5% for A.plurijuga and 24.5% for C.aesculifolia.Both species had higher survival and better growth at lower altitude,and no seedling emergence at any altitude.We conclude that assisted migration can be implemented for each species by an upward attitudinal shift within,and not exceeding,400 m beyond their present upper altitudinal limit of distribution.Our results indicate that for many species that show altitudinal gradients at regional scales,unless current climate conditions change,the potential to establish outside their range is minimal.  相似文献   

14.
立地环境因子对小油桐冻害影响的调查研究   总被引:1,自引:0,他引:1  
贵州罗甸县2008年凝冻低温使小油桐受到严重冻害。2009年1~3月平均温度均在12℃以上,为有效了解小油桐的适生环境,对不同坡向、海拔、坡位区域中小油桐的冻害情况进行调查研究。结果表明:不论海拔高低,坡向中阴坡和半阴坡小油桐冻害显著,半阳坡和阳坡冻害程度相对较轻;海拔600 m以上小油桐的冻害严重,最严重冻害发生在海...  相似文献   

15.
在福建霞浦、仙游、永泰、南平延平区、邵武市、永安市和上杭县开展柳窿桉9号引种适应性试验研究,结果表明:柳窿桉9号适应性和速生性较强,在一般立地条件下造林(Ⅲ类地)成活率可达95%以上,中龄林保存率达85%左右。其速生性虽略比尾巨桉DH32-29差,但1年生平均树高可达2.0 m以上,2年生树高、胸径分别可达5.0 m、5.0 cm以上,尤其在低海拔山地不受冻或轻微受冻的情况下,其速生性较为明显;柳窿桉9号树干通直、径粗,抗风、抗旱和抗病虫害能力均较强。但柳窿桉9号对低温极为敏感,耐寒性有限,只可耐-2.0~-2.5℃的低温,在闽西北地区受冻几率大,在闽东南地区海拔300 m以下的山地种植受冻较轻,可以恢复正常生长。该无性系在福建中亚热带极端低温不低于-3℃的区域低海拔山地有种植前景,尤其适合闽东南沿海海拔300 m以下的山地栽培。  相似文献   

16.
选择了高海拔和低海拔2种立地条件,研究了不同立地对马尾松和湿地松生长和产脂量的影响,结果表明:高海拔地区的湿地松胸径和树高均显著低于低海拔,高海拔地区湿地松平均胸径为7.65cm,平均树高为4.23m;低海拔湿地松平均胸径为10.69cm,平均树高为6.93cm。无论是高海拔地区还是低海拔区上,湿地松的单株日产脂量均显著大于马尾松,高海拔地区湿地松的单株日产脂量为1.33g,马尾松为0.41g,低海拔区湿地松的单株日产脂量为3.96g,马尾松为2.36g;在不同海拔高度上,两树种的产脂量均为低海拔区大于高海拔地区。  相似文献   

17.
为了解广东梅县阴那山省级自然保护区蝶类资源和物种多样性情况,2021年7—12月利用样线法进行观测调查。结果表明,阴那山自然保护区共调查到蝶类10科、75属、110种;区系组成主要以东洋界为主,古北界和东洋界共有为辅;随海拔升高,蝶类群落属数、种数、个体数量、优势度指数、丰富度指数和多样性指数均表现为先增长后下降的单峰趋势,并均在401~600 m达到最大值,高海拔地区蝶类群落的均匀度指数大于低海拔地区;相邻海拔地区蝶类群落的相似性较高,且高海拔与低海拔间蝶类种类存在明显差异。以期为阴那山省级自然保护区预测气候变化、保护蝴蝶资源和评价生态环境等提供基础资料和理论依据。  相似文献   

18.
In southern Spain, the Cazorla Mountains (500–2,100 m a.s.l.) have supplied construction timber from black pine (Pinus nigra Arn.) for buildings and ships since at least the Middle Ages. To establish the age and provenance of wooden cultural heritage originating from this area, well-replicated long-span chronologies are needed. Old-living trees occur at high elevations, whereas many historical timbers originated from lower altitudes; hence, crossdating possibilities were questionable. To assess the potential of this species for the development of a multi-millennia tree-ring data set with living trees and historical timbers for the western Mediterranean, we developed four ring-width chronologies along the circa 1,000 m altitudinal range of black pine in these mountains and examined crossdating patterns and climate–growth responses along with altitude and through time. Teleconnections with other Iberian and Mediterranean tree-ring data were also tested. A well-replicated chronology spanning AD 1331–2009 was obtained at the upper site, while lower elevations delivered shorter chronologies. Similarity among chronologies and responses to climate were dependent on elevation. Tree-ring width was negatively related to temperature in previous late summer and positively to February–March, whereas precipitation had an opposite effect; some negative influence of early summer temperature was also observed. However, growth responses were rather unstable throughout the twentieth century. These chronologies showed good tele- and heteroconnections with conifer chronologies from Iberia, northern Morocco and Turkey, evidencing the existence of a common macroclimatic signal, which also varied along with elevation. The relevance of these results for dendrohistorical studies is discussed.  相似文献   

19.
南岳衡山不同海拔的昆虫多样性   总被引:2,自引:0,他引:2  
于2005年3~5月份在衡山不同海拔高度设样地采集昆虫标本并进行相关分析。结果表明:昆虫种类和数量随时间和海拔高度的变化而有较大差别,在本次调查中双翅目、膜翅目、鞘翅目在衡山是比较稳定的优势种群;优势度指数因海拔高度、采集标本时间不同而有差异;不同采集时间不同海拔高度的多样性指数相差不大;中海拔地区的均匀度指数在每个采集时间里都较高、低海拔地区的稍高。  相似文献   

20.

? Introduction

Information on spatial variability in tree radial growth is essential for improving predictions of forest ecosystem responses to climate change. To date, researchers have designed models to simulate the potential distribution area of major forest types under different climate change scenarios in Northeast China, but little is known about the spatial variability of tree growth in response to climate.

? Materials and methods

We used a dendroecological technique to examine the climate–growth relationship of six dominant tree species on seven sites varying in altitude on Changbai Mountain in Northeast China, to explore whether the spatial variability of tree growth is an indicator of regional climatic forces, and whether simulation results generated by models can accurately reflect this in tree radial growth.

? Results

Fifteen site-specific species can be distinguished species at or near their upper limit distribution from those at the lower distributions. Species differences were more important than altitude differences in influencing species’ site-specific radial growth. Precipitation, temperature, and soil moisture together constitute the major factors limiting tree radial growth.

? Conclusion

We found the distribution area of dominant tree species on Changbai Mountain will shift upward; growth of Korean pine will not decline at its lower limit of distribution and will not eventually even disappear from forest communities in those areas.  相似文献   

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