不同嫁接方法对黄枝油杉成活率及生长的影响

为丰富黄枝油杉（Keteleeria davidiana var. calcarea）繁育方法，以铁坚油杉（Keteleeria davidiana）做为砧木，以黄枝油杉枝条做为穗条，研究不同嫁接方法与嫁接时间对黄枝油杉成活率及生长的影响。结果表明，不同嫁接方法对穗条成活率影响显著，切接法和插皮接法成活率较高，劈接法最低。不同嫁接方法对穗条生长影响不显著。不同嫁接时间对穗条成活率影响显著，2月1日嫁接成活率最高（72.8%）,4月1日最低。不同嫁接时间对穗条生长影响显著，2月1日嫁接的穗条新梢长度、新梢粗度最大（37.0和0.45 cm）,4月1日最小（28.9和0.38 cm）。适合黄枝油杉嫁接的时间是早春季节，植株尚未萌动前；最适合的嫁接方法是切接法，其次是插皮接法。     

珍稀频危植物扦插繁殖技术研究

１研究材料采用扦插繁殖的种类有长果秤锤树、秤锤树、柔毛油杉、黄枝油杉、香果树、银钟花、水杉、银杏、长柄双花木、连香树、福建柏、长苞铁杉、白豆杉、南方铁杉、秃杉、夏蜡梅、金钱松、珙桐、光叶珙桐、资源冷杉、水松、水青树、观光木、黄杉、穗花杉、领春木、天女...     

广西珍贵树种高效栽培技术（连载）

黄枝油杉 黄枝油杉是中国特有的古老树种，别名油杉，为松科常绿大乔木。高可达28米，胸径可达1．3米。树皮灰褐色或暗褐色，纵裂，片状剥落，叶子为线，长形、绿色，在侧枝上排成2列。花期3～4月，果期10～11月，球果圆柱形，直立，成熟时淡黄色或紫褐色，种鳞斜方状圆形或近圆，先端反曲，鳞片露出部分有密生的短毛，基部两侧耳状。     

黄枝油杉种苗质量分级标准研究

黄枝油杉由于其分布区狭窄,繁殖速度慢,资源少,是国家二级保护植物。为了更好地保护其种质资源,通过实验研究种苗质量分级标准。分别对2年生和4年生的黄枝油杉种苗性状特征描述,以地径和株高作为主要分级标准代表,运用Excel 2003和SPSS 26.0对种苗特征数据进行统计学相关分析、主成分分析、K均值聚类分析,将其种苗分别2年生和4年生分别分成了三级。2年生一级株高＞20 cm,冠幅＞11 cm,地径≥0.10 cm;4年生一级株高＞127 cm,冠幅＞56 cm,地径≥0.80 cm。2年生二级株高14~20 cm,冠幅8~11 cm,地径≥0.10 cm;4年生二级株高96~127 cm,冠幅38~56 cm,地径≥0.80 cm;2年生三级株高＜14 cm,冠幅＜8 cm,地径≥0.10 cm;4年生三级株高＜96 cm,冠幅＜38 cm,地径≥0.80 cm。     

江南油杉种质资源与苗木繁殖研究动态与展望

通过相关资料的查阅与收集,对江南油杉在我国天然种群资源的分布进行分析研究,揭示了江南油杉自然繁衍对生境的需求、过度砍伐利用是导致其濒危的原因,分析自然种群生境、染色体核型研究、育苗技术和引种驯化等方面的研究现状,以实现江南油杉资源保护与合理利用,并进一步研究江南油杉的人工林栽培技术和高效繁殖技术。     

黄枝油杉枯梢病

继在江永县低山丘陵石灰岩地区发现黄枝油杉(Keteleeria calcorea Cheng et L.K.Fu)后,今年5月下旬,我们在江永县考察中发现黄枝油杉枯梢病,经调查,江永县松柏公社和县林科所两处,此病的发病率达85％。主要为中幼龄树感病,中龄树以侧枝感病多,幼龄树主梢侧梢均有发生,轻则针叶枯黄,重则几乎每个春发主梢和侧梢均被病菌侵染,引起大     

油杉属植物研究动态

从系统分类学、植物地理学、繁殖生物学及保护生物学4方面对油杉属植物研究动态进行综述,结果表明,油杉属植物集中分布在中国南方地区,具有小种群的特点;通过对其细胞学、同工酶及植物地理学研究,对该属植物的分类及系统发育具有重要意义。油杉属发达的种翅可以使种子进行远距离传播,有利于种群的扩展,雄球花花粉成熟期较集中、寿命短,导致其结实率低;种子萌发条件的特殊要求,影响其自然更新。并提出了通过人工授粉、促进种子萌发、扦插和嫁接等人工辅助繁殖实现对我国油杉属植物资源的保护与利用,从而为该属植物的进一步研究奠定了理论基础。     

融安发现珍贵树种——黄枝油杉

最近,融安县发现珍贵树种——黄枝油杉,数量达50多棵。其中,最大的一棵胸围直径达136厘米,树高24米,盖地面积约20平方米。     

五峰发现三大珍稀树种原生群落

继湖北五峰后河国家级自然保护区珙桐、红豆杉等珍稀植物群落发现后 ,五峰植物考察又获新发现。近日 ,省林业专家王罗荣高级工程师与五峰土家族自治县林业局林业科技人员在五峰植物考察过程中 ,发现锁金山天然黄杉原生群落近133 3hm2 、木荷原生群落 5 3 3hm2 ,同时 ,发现泗洋河沿岸近 2 0km长的黄枝油杉原生群落分布带 ,面积达 2 6 6 7hm2 。黄杉、黄枝油杉均系国家珍稀濒危树种 ,木荷是珍贵用材树种。初步考察后专家称 ,三大珍贵树种原生群落分布之集中、面积之大、保存之完好在国内实属少见。此次发现对该地区生物多样性保护和植物种质…     

湖南首次发现黄枝油杉

根据对过去有关文献的查阅,珍贵用材树种同时又为古孑遗树种的黄枝油杉Keteleeria Calcorea cheng et T.K.Fu,本省未见有记载。以全国而言,则主要见于中亚热带南部低山丘陵区。为了     

中国西南特有木兰科植物石山木莲的修订

石山木莲Manglietia aromatica var.calcarea （ X.H.Song ） Sima et S.G.Lu为中国西南部特有植物，仅分布于贵州和广西，过去一直被忽视或作为木莲M.fordiana Oliver的变种。通过与木莲和香木莲M.aromatica Dandy的性状比较表明，它是一个好而明确的类群，与香木莲近缘而与木莲远缘。文中将其作为香木莲的变种，并重新组合命名为 M.aromatica var.calcarea （X.H.Song） Sima et S.G.Lu。     

石漠化山地造林初期生态效益评价

以贵州省修文县石漠化造林项目为例,对石漠化山地幼林期生态效益评价方法进行探讨,从项目实施后森林资源总量、植被覆盖度、林木生长量、群落生物量、持水量,评价林分涵养水源效益;以表土侵蚀和泥沙含量变化、土壤有机质、N、P、K含量为评价指标,评价林分固土效益。对石漠化山地造林项目生态效益的评价进行了探讨,旨在为石漠化山地生态恢复提供参考。     

Effects of resource plant size on rooting of <Emphasis Type="Italic">Dryobalanops lanceolata</Emphasis> cuttings

 Cuttings from older trees of the Dipterocarpaceae generally lose their ability to root. However, branches in a canopy of adult dipterocarps are a possible source of cuttings because they show juvenile characteristics in architecture due to “adaptive reiteration”, suggesting physiological rejuvenation. Effects of resource plant size on the rooting of cuttings and the possibility of using cuttings from reiterated branches of adult trees were studied for Dryobalanops lanceolata, an emergent dipterocarp species. A cutting experiment with non-mist propagators was conducted for cuttings collected from resource plants of four different size classes: <2 m, 2–5 m, 8–15 m, and 70 m in height. The smallest size class included two different age classes: <2 and >2 years old. Cuttings from the tallest resource plant were collected from reiterated branches. Rooting percentage was negatively correlated with resource plant size: 77–78% for resource plants <2 m, 63% for 2–5 m, 36% for 8–15 m, and 0% for 70 m. Rooting percentages of cuttings collected from different individuals were not different for the 2–5 m tall class, while they were significantly different for the 8–15 m tall class. Resource plant size was negatively correlated with the number of roots for rooted cuttings. No significant relationship was observed between resource plant size and mean length of each root, total root length or total root dry weight for rooted cuttings. The results suggest the possibility of collecting cuttings from relatively large resource plants up to 15 m tall and >20 years old if we chose good individuals for resource plants. The results, however, show the difficulty in using reiterated branches of adult trees as a source of cuttings for D. lanceolata. Received: October 15, 2001 / Accepted: November 11, 2002 Acknowledgments We express our sincere thanks to Dr. S. Tamura, Dr. K. Ogino, and Mr. A.A. Hamid for their kind support. The tree tower was constructed in a cooperative project between Japan and Sarawak supported by the Ministry of Education, Culture, Sports, Science and Technology, Japan (Grant NP0201). The cutting experiment was partly funded by the Nippon Life Insurance Foundation and the Japan Society for the Promotion of Science (JSPS-RFTF96R16001). Correspondence to:A. Itoh     

Seasonal nutrient dynamics in white pine and white spruce in response to environmental manipulation

Seasonal retranslocation in white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss) was examined in response to silvicultural treatments (scarification, annual fertilization application, and annual control of competing vegetation with herbicide) that changed both environmental conditions and the growth rate of the trees. Four years after plantation establishment and initial treatment, nutrient accumulation in current-year needles of white pine and retranslocation from 1-year-old needles were increased following the vegetation control treatment, which increased resource availability (nutrients, water and light) and, hence, growth rate. Nutrient accumulation also increased in current-year white spruce needles following the same treatment, whereas retranslocation decreased in 1-year-old white spruce needles. Correlations of retranslocation (N, P and K) with growth rate (shoot biomass increment) showed a strong positive relationship for white pine and a negative relationship for white spruce. Retranslocation of K was correlated with foliar and soil K concentrations; the availability of this nutrient was also significantly reduced by vegetation control. A general theory for the control of nutrient retranslocation in conifers, which is not based exclusively on either sink strength or soil nutrient availability, is proposed. We conclude that retranslocation response is species specific and related to the potential phenotypic growth response to changing environmental conditions and to short-term imbalance in the supply versus the demand for nutrients.     

Soil calcium,nitrogen, and water are correlated with aboveground net primary production in northern hardwood forests

Multiple soil resources could limit aboveground net primary production (ANPP) in temperate forests, but most studies have focused on nitrogen (N) availability. We tested a suite of resources including water, multiple measures of N, phosphate (PO₄), and extractable ions (calcium (Ca), potassium (K), magnesium (Mg)) as correlates of ANPP across a glacial landform gradient in northwestern Lower Michigan. Our goals were to identify resource correlates of ANPP that could potentially limit productivity, to characterize productivity partitioning to leaves (ANPP_L) and wood (ANPP_W) across the gradient, and to test soil resource correlates of partitioning. We measured soil resource availability and annual ANPP at 13 sites, and fit models of ANPP_W and ANPP_L as functions of each resource. We used Akaike's Information Criterion to assess empirical support for models with different functional forms. ANPP_W was best correlated with Ca, with a relationship that was asymptotic beyond the four lowest-productivity sites. Both Mg and K covaried with Ca; Mg was also supported as an ANPP_W correlate. Soil water and sum of ammonium (NH₄) and nitrate (NO₃) (ΣN) explained substantial ANPP_W variance, but with weaker support than for Ca. ANPP_L was best correlated with ΣN; NO₃ received support, while Ca received less support but still explained substantial ANPP_L variance. These results suggest a potential role for Ca in regulating ANPP, at least in low-productivity sites, while reaffirming the importance of both N and water availability. Partitioning of annual production to ANPP_W as a fraction of total ANPP was related to Ca and soil water, but only weakly to ΣN. Production was partitioned equally between ANPP_L and ANPP_W at low fertility, but ANPP_W exceeded ANPP_L by 24% at maximum productivity. Given this shift in partitioning, measuring only ANPP_W but assuming that ANPP_L scales proportionately would overestimate ANPP at higher fertility sites. Although correlative, our results suggest that ANPP is constrained by some combination of N, Ca, and water, and provide motivation for experimental manipulations of these resources to better understand forest responses to human influences. If northern temperate forests are strictly N-limited, as suggested by much of the literature, then anthropogenic N deposition should enhance ANPP. In contrast, if ANPP is limited, or co-limited, by Ca or by soil water, then anthropogenic change (altered precipitation, base cation leaching), could counteract production gains from N deposition.     

Quercus species differ in water and nutrient characteristics in a resource-limited fall-line sandhill habitat

We compared co-occurring mature Quercus laevis Walt. (turkey oak), Q. margaretta Ashe (sand post oak) and Q. incana Bartr. (bluejack oak) trees growing in resource-limited sandhill habitats of the southeastern United States for water and nutrient characteristics. The Quercus spp. differed in their distribution along soil water and nutrient gradients, and in their access to and use of water, even though the study year was wetter than average with no mid-season drought. Quercus laevis had the greatest access to soil water (least negative pre-dawn water potential, psi(pd)) and the most conservative water-use strategy based on its relatively low stomatal conductance (g(s)), high instantaneous water-use efficiency (WUE), least negative midday water potential (psy(md)) and high leaf specific hydraulic conductance (K(L)). Quercus margaretta had the least conservative water-use characteristics, exhibiting relatively high g(s), low instantaneous WUE, most negative psi(md), and low K(L). Quercus margaretta also had a low photosynthetic nitrogen-use efficiency (PNUE), but a high leaf phosphorus concentration. Quercus incana had the poorest access to soil water, but intermediate water-use characteristics and leaf nutrient characteristics more similar to those of Q. laevis. There were no species differences for photosynthesis (A), leaf nitrogen on an area basis, or seasonally integrated WUE (delta13C). Both A and g(s) were positively correlated for each species, but A and g(s) were generally not correlated with psi(pd), psi(md) or delta psi(pd-md). Although we found differences in resource use and resource status among these sandhill Quercus spp., the results are consistent with the interpretation that they are generally drought avoiders. Quercus laevis may have an advantage on xeric ridges because of its greater ability to access soil water and use it more conservatively compared with the other Quercus spp.     

世界紫胶资源现状与利用

对南亚和东南亚的几个主要紫胶生产国的紫胶资源现状和利用情况进行了比较, 从资源总体情况评价, 中国更加丰富而具有潜力, 近年其他紫胶生产国紫胶产量下降, 而中国紫胶林地面积和紫胶产量稳步上升.应充分利用资源优势, 使紫胶产业在流域生态环境保护、区域社会经济发展上发挥更大作用.     

森林资源与环境价值分析与补偿问题研究

森林资源经营过程中存在政策失灵、市场失灵与制度失灵,需要采取适当的措施进行调整,这对于促进森林资源可持续经营具有重要意义。解决上述失灵的重要手段是制定反映森林资源经营的全价值,价值是由市场和人们的支付意愿所决定,因此,评价森林资源的价值必须以市场为基础,评价方法分为显示偏好法和表明偏好法两种。森林资源价值评价是制定价格的基础,森林资源价格的确定应当采取边际机会成本的方法,边际外部成本可以采取补偿或者征税等不同方式加以解决。Faustmann模型是评价森林资源的重要方法,百余年来,这方面的研究已经取得重要进展,森林资源的直接使用价值和非使用价值需要均衡,风险等因素也相继引入分析视野,文中对这两个方面的模型结构进行了表述。     

南宫自然保护区旅游资源及开发条件分析

对南宫自然保护区旅游资源中生物景观资源、地理景观资源、水文景观资源、天象景观资源、人文景观资源和旅游开发条件进行了分析评价,总结出保护区旅游开发的优势和制约因素。     

关于对林木资产核算的初探

森林资源资产化管理已成为我国林业理论和实务工作者们普遍关注的问题,森林资源资产化管理的关键就是要将森林资源作为一种有价值的资产加以经营和管理,而森林资源资产的核算是资产化管理的基础;同时,鉴于森林资源资产是一个综合的概念,包括了林木、林地、森林景观等,其中林木资产是主体,因此,如何做好林木资产的会计核算工作就成为森林资源资产化管理的关键。