九连山碟斗青冈群落结构及小气候特征分析

根据16个样方共1600m2面积调查统计,九连山碟斗青冈(Cyclobalanopsis disciformis)群落共有维管束植物45科64属83种,区系地理成分以热带、泛热带分布的热带性成分为主,占总属数的75.81%。群落最小面积为1600m2。物种多样性Shannon-Wiener指数为4.58,均匀度为84.4%。高位芽植物占总数的82%,以中型叶、革质叶、单叶和全缘叶占优势。该群落与中亚热带常绿阔叶林有显著区别,具有典型的亚热带常绿阔叶林沟谷雨林的特征,属于从中亚热带向南亚热带常绿阔叶林过渡的类型。群落垂直结构层次明显,可分为乔木层、灌木层和草本层,并有非常丰富的层间植物。目前几个优势种群的年龄结构趋于暂时的稳定。茂密而结构复杂的常绿阔叶林,调节夏季最高和平均气温的能力较强,调节冬季最低和平均气温的能力较弱,林内较林外极值呈现夏低冬高的特点。茂密而结构复杂的常绿阔叶林具有较大的促进降水作用,保持空气湿度具有较大作用。     

Biocycle of nitrogen in a Cyclobalanopsis glauca-dominated evergreen broad-leaved forest in East China

The nitrogen (N) cycling was elucidated in a 40-year-old subtropical evergreen broad-leaved forest dominated by Cyclobalanopsis glauca growing on red soil in Zhejiang Province, East China. The concentrations of N in the representative species ranged from 0.49% to 1.64%, the order of which in various layers was liana and herb layers > understory layer > tree and subtree layers; in various organs was leaf > branch > root > trunk; and aboveground parts > underground parts. The sequence of the concentrations of N in C. glauca was understory > tree > subtree layer; young and high-growing > old organs; reproductive > vegetative organs. Seasonal dynamics of the concentrations of N in C. glauca in the tree and subtree layers was comparatively stable. It was lower in autumn (October) in root, branch, and leaf in the tree layer, and low in January in the understory. There was no evident change in regularity of the concentrations of N in varying diameter classes. The concentrations of N in the litterfall, precipitation, throughfall, litter layer, and soil were 0.74%–2.30%, 0.000,038%, 0.000,09%, 1.94%, and 0.59%, respectively. The standing crop of N in the plant community was 1,025.28 kg/hm², accumulation in the litter layer was 224.88 kg/hm², and reserve in the soil was 55,151 kg/hm². Annual retention of N was 119.47 kg/hm², return was about 84.13 kg/hm², among which litterfall was 78.49 kg/hm² and throughfall, 5.64 kg/hm². Annual absorption of N was 203.60 kg/hm². Annual input of N through incident precipitation was 4.88 kg/hm². Compared with other forest types, cycling rate of N in the community was lower than in deciduous broad-leaved forests, rain forests, and mangroves, and was moderate in evergreen broad-leaved forests. N use efficiency of this forest was moderate among the forest types cited. According to the characteristics of the biocycle of phosphorous, it was concluded that N availability in the soil of this forest was not lower, and phosphorous not N was the limiting factor in the growth of plants in this community. __________ Translated from Acta Ecologica Sinica, 2005, 25(4): 740–748 [译自: 生态学报, 2005, 25(4): 740–748]     

滇中岩溶高原滇青冈原生林植物水分利用来源的稳定同位素分析

为阐明滇中岩溶高原滇青冈Cyclobalanopsis glaucoides原生林植物水分利用机理及其对岩溶干旱生境的适应策略,运用氧稳定同位素技术,分析了滇青冈,云南木樨揽Olea yue nnanensis,清香木Pistacia weinmannifolia等3种不同年龄阶段常见优势木琴植物小枝木质部水分及土壤水、表层岩溶带水氧同位素值的相关性,确定植物水分来源,并通过IsoSource模型计算不同潜在水源对滇青冈原生林的贡献。结果表明：滇青冈及其伴生的乔木水分利用层位及利用比例呈现时空差异,并形成明显的水分竞争关系。旱季,滇青冈、成熟云南木樨揽、幼龄清香木主要利用55～115 cm深层土壤水,成熟的滇青冈和清香木对表层岩溶带水利用比例增加。雨季,成熟的滇青冈、云南木樨揽、清香木和幼龄清香木因大气降水对浅表层土壤的补给主要利用20-55cm土壤水,利用比例分别为100％,33．3％,66．0％,37．4％,幼龄植株对表层岩溶带水的利用比例大于成熟植株。图2参23     

灰木莲、巨尾桉和厚荚相思人工林土壤微生物量及酶活性比较

为了解灰木莲、巨尾桉和厚荚相思3种人工林地的土壤肥力变化,为制定相应的营林措施提供参考,对3种8年生人工林0 ～ 20cm土层的微生物数量及土壤酶活性进行比较.结果表明:(1)不同树种的土壤微生物总量为灰木莲＞厚荚相思＞巨尾桉.同一树种在一年四季中的变化是:灰木莲林地夏季＞冬季＞秋季＞春季;巨尾桉林地秋季＞春季＞夏季＞冬季;厚荚相思林地秋季＞春季＞冬季＞夏季.(2)3种林地土壤的三大类群微生物数量特征表现为细菌最多,真菌数量最少,但在不同季节里有变化.灰木莲林地和厚荚相思林地的细菌数量明显大于巨尾桉林地;而巨尾桉林地的真菌和放线菌数量在春夏两季均大于另外两种林地,但秋冬两季则是3种林地中最少的.(3)3种林地的土壤蛋白酶活性在春季基本持平,但在夏季和冬季的差异却达到极显著水平;而3种林地的土壤过氧化氢酶活性均在夏季和冬季出现两次高峰,冬季的酶活性最大,差异达显著水平.分析表明不同树种对林地土壤微生物数量、组成以及土壤酶活性有重要影响.     

突脉青冈天然林优势种直径结构规律探讨

采用样地调查方法,利用5个概率密度函数对突脉青冈天然林中4个优势种(突脉青冈、细柄阿丁枫、白楠、罗浮栲)的直径分布结构特征进行探讨,同时利用L-PRM模型、G-PRM模型拟合4个树种的林分直径分布概率函数。结果表明:除了正态分布,4个树种的林分直径都服从对数正态、威布尔、伽玛分布,而罗浮栲也服从贝塔分布;可用L-PRM模型、G-PRM模型模拟与预测细柄阿丁枫和罗浮栲各个径阶的林木株数。研究结果可为有效地预估林分生长,为更好地优化管理、经营突脉青冈天然林提供参考。     

低温胁迫对淡竹2个抗寒性生理指标的影响

选择13个区域的淡竹叶片为试材,分别在0、-5、-10、-15、-20、-25℃下进行低温胁迫处理,测定其电导率和脯氨酸含量的变化,电导率结合Logistic方程计算出淡竹的半致死温度。通过脯氨酸含量分析和半致死温度的计算,综合分析不同区域淡竹抗寒性的生理生化指标,推测其抗寒性强弱:来源于烟台林科院、烟台昆嵛山、潍坊的淡竹抗寒性较强,来源于日照、沂源、东营、济南、临沂、胶南、泰安的淡竹抗寒性中等,来自浙江、江西、江苏的淡竹抗寒性最弱。     

栎属和青冈属的新组合(英文)

<正> 1. Quercus aliena B1. var. pekingensis Schott. f. alticupuliformis (Liouet S. X. Li)H. W. Jen et L. M. Wang comb. nov.—Q. aliena B1. var. jeholensis Liou et S. X. Li in F1. Lign. N. -E.Chin. 219. 1955. —Q. aliena B1. var. alticupuliformis H. W. Jen et L. M.Wang in Bull. Bot. Res. 4 (4):197. f. 3. 1984.2. Quercus serrata Thunb. var. tomentosa (B. C. Ding et T. B. Chao)Y. C. Hsu et H. W. Jen comb. nov.—Q. glandulifera B1. var. tomentosa B. C. Ding et T. B. Chao F1.Honan 《河南植物志》 1:248. 1981.3. Quercus senescens Hand. -Mazz. var. muliensis (Hu)Y. C. Hsu etH. W. Jen comb. nov.     

灰叶荆群落生长和更新能力的研究

本文对厦门地区灰叶荆群落的生长和更新能力进行了研究。该植物3、4年生群落植株基径年增量为0.71～0.91cm;当年播种植株高和基径年增量分别为299.4和3.38cm;4、5年生群落母桩萌条的高和基径年增量分别为304.4～264.0cm和2.25～1.55cm。光照,温度和雨量是影响该植物生长和萌更的主要生态因子。光照的差异使群落内个体分化为被压木和优势木两类。该植物自然更新能力差,但其种子发芽力强,耐贮;影响种子发芽的主要因素是气温和采种期。     

青冈常绿阔叶林的太阳辐射分布特征

通过野外定位观测，对青冈（Ｃｙｃｌｏｂａｌａｎｏｐｓｉｓｇｌａｕｃａ）常绿阔叶林太阳辐射分布特征进行了研究．结果表明，青冈林反射辐射、透射辐射和吸收辐射的季节动态与太阳总辐射的季节动态相似，各辐射分量均为夏季最大，冬季最小，四季中群落的反射率、透射率和吸收率分别为１６％～２２％、９％～１２％和６７％～７４％．林冠层对光强的衰减率达８０％～９０％，且衰减率随太阳高度角的增大而增大．群落中部以下光强的衰减很小     

Potential of Nicotiana glauca (Grah.) as a source of resistance to black root rot Thielaviopsis basicola (Berk. and Broome) Ferr. in tobacco improvement

Nicotiana glauca, a wild relative of Nicotiana tabacum, is an attractive potential source of black root rot (Thielaviopsis basicola)‐resistant germplasm. Moreover, it shows a resistance or tolerance to PVY, TEV, anthracnose and powdery mildew. In this study its potential as a source of resistance to black root rot caused by Th. basicola was investigated. Nicotiana glauca GG (2n = 2x = 24) was crossed as male with two N. tabacum TT (2n = 4x = 48) flue‐cured cultivars: ‘BY103’ and ‘K 326’, both of which are susceptible to black root rot. Amphihaploid F₁ TG (2n = 3x = 36), amphidiploid TTGG (2n = 6x = 72) and sesquidiploid TTG (2n = 5x = 60) hybrids were obtained. The resultant sesquidiploid hybrids were used as maternal components in backcrossing to N. tabacum and a segregating post‐sesquidiploid TTg (2n = 5x = 52–54) offspring was obtained. Amphihaploids exhibited a level of resistance to black root rot characteristic of N. glauca. The expression of resistance varied in the sesquidiploid generation, possibly reflecting cytological instabilities in that progeny. A wide variation in response to black root rot was found for post‐sesquidiploids a clear reflection of extensive chromosome segregation in that hybrid generation.