In order to explore the internal mechanism of C/N ratio regulating the decomposition of Cunninghamia lanceolata litters, C. lanceolata litters with different C/N ratios（40.6, 30.5, 20.3） and untreated（60.9, C/N ratio） regulated by nitrogen addition was placed in the C. lanceolata plantations managed by understory vegetation preservation and undergrowth vegetation removal, and the dynamic changes of decomposition rate and enzyme activity of C. lanceolata litters were studied within 300-d decomposition. C/N ratios of approximately 40.6 and 30.5 could promote the decomposition of C. lanceolata litters; In general, reduction of the initial C/N ratio can promote the activities of cellulase and urease in the decomposition process of C. lanceolata litters, and had an inhibitory effect on the activities of acid phosphatase, peroxidase and polyphenol oxidase. Compared with undergrowth vegetation removal, undergrowth vegetation preservation was more conducive to the decomposition of litters and the increase of enzyme activity of C. lanceolata litters, however, high nitrogen input is more likely to inhibit the decomposition and enzyme activities of leaf litter of C. lanceolata litters. The weight loss rate of C. lanceolata litters was significantly positively and linearly correlated with the activities of various enzymes, and the equation of cellulase activity and weight loss rate has the best fitting effect. Studies have shown that that C/N ratios of approximately 40.6 and 30.5 is conducive to the improvement of enzyme activity of C. lanceolata litters, butits decomposition speed is affected by the stand environment.

Chloroplast genomes of 4 species of yellow Camellia including Camellia xiashiensis were assembled from whole-genome resequencing data for annotation and comparative analysis. The results showed that the 4 species of yellow Camellia had highly similar chloroplast genome sequences with lengths ranging from 156 657-157 046 bp, which were predicted to annotate 134 genes, including 89 protein-coding genes, 8 rRNAs and 37 tRNAs. Comparative analysis revealed that the chloroplast genomes of yellow Camellia were highly conservative in structure and evolution, and they had similar codon preferences without extensive gene inversion and rearrangement. Polymorphism analysis revealed highly variable fragments such as rps16 and ycf1 in the chloroplast genomes of yellow Camellia, which can be applied as molecular markers. The phylogenetic tree constructed based on the chloroplast genome data had a high degree of accuracy, indicating that the publication of the chloroplast genome was important for the phylogenic study of yellow Camellia.

为探究大径材培育目标下间伐和施肥对杉木(Cunninghamia lanceolate)近熟林土壤微生物特征的影响,了解微生物生物量碳氮与微生物群落结构的相互关系,以福建省洋口国有林场 31 年生的杉木近熟林为对象,设置间伐(T)、间伐+施肥(TF)、对照(CK,不间伐不施肥)3 种处理,研究不同处理下杉木近熟林土壤微生物生物量碳(SMBC)和土壤微生物生物量氮(SMBN)含量及其化学计量特征(SMBC/SMBN)、土壤微生物熵碳(qMBC)和土壤微生物熵氮(qMBN)的变化规律,采用高通量测序技术分析不同处理下土壤微生物群落结构差异.结果表明,T和TF处理能提高SMBC含量,增大qMBC和SMBC/SMBN,且TF处理的提高幅度较大;T处理会降低SMBN含量和qMBN.经T和TF处理后土壤真菌群落优势菌门的丰富度和多样性指数升高,而细菌与之相反.相关分析表明,SMBN含量、qMBN和SMBC/SMBN与土壤细菌和真菌群落结构关系密切;SMBN含量和qMBN与土壤真菌丰富度、多样性指数呈显著负相关(P<0.05).综合认为,T和TF处理能够改善林地土壤微生物生存环境,促进真菌生长和繁殖,有利于提高土壤肥力,为杉木大径材培育提供良好的土壤条件.

The growth, biomass, nutrient content and accumulation as well as the vertical distribution of nutrient accumulation in Cunninghamia lanceolata plantation across densities of 1800, 3000, 4500 trees·hm-2 were stu-died in order to provide scientific basis for efficient cultivation of C. lanceolata plantation. The total amounts of nutrients accumulated in C. lanceolata plantation with 1800, 3000, 4500 trees·hm-2 were 1311.57, 2531.55 and 2307.33 kg·hm-2, respectively. There were significant variations among different densities. Under the same density, the order of nutrient content and accumulation in C. lanceolata plantation was total N > total K > total Ca > total Mg > total P. Moreover, the amount of nutrients in trunk and bark decreased with the increases of tree height. The amount of nutrient accumulation in persistent withered branch and leaf were allocated from middle to the upper part of tree, while the opposite was observed for fresh branch and leaf. N accumulation increased with the increases of stand densities, while the other nutrients first increased then decreased. The order of the amount of nutrient accumulation in trunk, bark, root, persistent withered branch, persistent withered leaf and litter among different densities was 4500 > 3000 > 1800 trees·hm-2, and was 3000 > 1800 > 4500 trees·hm-2 in fresh branch and leaf, and 1800 > 3000 > 4500 trees·hm-2 in understory. Under the densities of 1800 and 4500 trees·hm-2, the nutrient distribution ratio in bark was the largest, accounting for 21.6% and 19.4%. In 3000 trees·hm-2, the distribution ratio of fresh leaves reached its maximum, accounting for about 22.9%, and the next was fresh branches, which had a distribution ratio of about 17.8%. 3000 trees·hm-2 was the most appropriate density for nutrient accumulation and distribution in C. lanceolata plantation.

开展采穗母树栽植密度、伏干长度,覆土厚度,初始萌芽条平茬技术对比试验研究,优化栽植密度、伏干长度、埋干覆土厚度、芽基长度和密度等杉木"带冠埋干"采穗圃树形处理关键技术参数.方差分析结果表明:栽植密度对年有效穗条产量影响极显著,伏干长度对年有效穗条产量、穗条鲜质量、穗条长度影响极显著;平伏干覆土厚度、芽基长度、芽基密度,以及芽基长度、芽基密度交互作用,对年有效穗条产量、穗条长度、穗条鲜质量、穗条含水率有极显著影响.通过多重比较和基于MSM-PP技术的组合筛选,确定了采穗母树处理的最佳技术方案:栽植密度80 cm、伏干长度70 cm、覆土厚度6 cm、芽基长度0.5 cm、芽基密度0.5 cm×1.0 cm.研究结果对提高杉木"带冠埋干"采穗圃的穗条产量和质量具有重要意义.

以福建省南平市王台镇100年生人工杉木林为研究对象,分析4种地形(西南坡地、西北坡地、山凹地、山洼地)0～20、20～40、40～60 cm处的土壤理化性质及林下植被多样性的差异,采用方差分析法分析地形因素对两类指标的影响,采用相关性分析方法分析两类指标间的内在联系.结果表明:同一土层下非毛管孔隙度、全磷、速效磷和速效钾受地形影响显著,总孔隙度和有机质多无显著影响,且非毛管孔隙度、有机质、全氮和速效钾总体表现在西南坡地最高,速效磷在山凹地最高,全磷等理化性质均表现在山洼地最高,西北坡地的土壤理化性质相对较低.4种地形下林分土壤除容重、全磷和全钾外,含水率等理化性质多随土层加深呈下降的趋势;相较草本层,灌木层多样性指数变化更为明显,且灌木层及草本层均表现为西北坡地最高,其次是西南坡地和山凹地,山洼地最低;该林分土壤含水率、毛管孔隙度、全磷及速效钾与灌木层及草本层林下植被多样性关系密切,且存在显著或极显著相关.可见,不同地形下土壤理化性质和植被多样性受地形影响较大.

研究不同C/N比对杉木凋落叶分解过程养分元素释放动态的影响,为杉木林科学经营管理提供参考.采用分解袋法对杉木凋落叶进行了为期300天的观测,凋落物设置4种C/N比:C/N比60.86(CK)、C/N比40.57(N1)、C/N比30.45(N2)、C/N比20.25(N3),测定林下植被去除和保留的杉木林内杉木凋落叶分解过程中的养分含量并进行分析.(1)在杉木凋落叶分解期间,其C/N、C/P比值均比初始值低,而N/P比值则大于初始值;(2)N、P、Ca和Mn浓度以CK处理较高,不同处理的P、Ca和Mn浓度差异显著;(3)分解期间,C、K、Ca、Mg均表现为养分释放,N表现为养分富集,P和Mn在分解180 d～300 d时表现为富集现象,但总体上表现为养分释放;(4)分解时间对7种元素(N、C、P、K、Ca、Mg、Mn)及3种元素比(C/N、C/P、N/P)的影响较大,N与林分呈显著负相关,C/N与林分呈显著正相关,不同C/N处理与Mn呈极显著负相关,其余元素与林分和C/N处理无显著相关性.(5)林下植被保留林分有利于C、K、Mg的释放,林下植被去除林分有利于N的富集,Ca的释放、P和Mn的释放和富集.在300 d的分解过程中,杉木凋落叶分解速率对于外源氮的输入具有低促高抑的响应,且随着分解时的延长,促进作用减弱,抑制作用增强.杉木凋落叶分解需要较低的C/N比值,同时对于P具有大量需求.研究成果可为杉木林的经营和管理提供科学依据.

为提高毛红椿(Toona ciliata)人工林生长质量,于2017年,在福建省洋口国有林场对15年生的毛红椿人工纯林进行抚育间伐试验,间伐强度分别为20％、40％(分别记为T20、T40),以不间伐林分为对照,探讨毛红椿人工林对抚育间伐的响应.结果 表明:间伐增加了毛红椿人工林林分高大林木的株数比例,间伐后3.5a的林分胸径/树高在24～32 cm/24～ 30 m的株数比例最大,而对照林分的胸径/树高在12～22 cm/18～24 m的株数比例最大.间伐提高了林木胸径、树高的生长量,与对照相比,伐后3.5a,间伐强度为20％、40％的林分胸径/树高分别提高了4.6倍、6.8倍/1.18倍、1.61倍.间伐明显提高了毛红椿林木单株材积的生长量,与对照相比,伐后3.5a,间伐强度为20％、40％的林分单株材积分别提高了1.80倍、3.60倍.在本试验条件下,间伐强度40％更有利于人工纯林的生长.

为了解不同密度杉木(Cunninghamia lanceolata)林各组分C、N和P含量及其化学计量特征,以3种林分密度(1800、3000和4500株/hm2)杉木林为研究对象,测定杉木林鲜叶、凋落物及土壤的全C、全N和全P含量,计算其化学计量比,并进行相关性分析.结果表明,不同林分密度间,鲜叶全C、全N和全P含量,凋落物全C和全P含量及土壤全C含量差异不显著,凋落物全N含量,土壤全N和全P含量差异显著;随土壤深度的增加,全C、全N和全P含量均降低;3种密度林分的全C、全N和全P含量均表现为鲜叶>凋落物>土壤.鲜叶C:N和C:P随林分密度的增加先下降后升高,3种密度林分鲜叶N:P均>14.凋落物C:N和C:P均随林分密度的增加逐渐降低.C:N、C:P和N:P均表现为凋落物>鲜叶>土壤.3种密度林分土壤全C、全N和全P含量及其化学计量均呈极显著相关性,其余组分相关性较为复杂.不同密度杉木林生长均受到P限制,林分密度越大,受P限制越大.综合条件下,中等密度更有利于杉木生长与养分循环.

2018年10月-2019年3月,在福建省灵石森林公园实验室开展台湾肖楠种子不同贮藏方法、贮藏时间对比试验.结果表明:不同贮藏方法之间、不同贮藏时间之间的种子实验室发芽率均存在极显著差异,贮藏方法与贮藏时间之间交互作用也存在极显著差异;不同贮藏方法的种子含水率变化存在较大差异,种子含水率与种子实验室发芽率之间存在极密切的负向线性相关,相关系数为-0.9215.台湾肖楠阴干种子的最佳贮藏方法为低温贮藏,贮藏150 d种子实验室发芽率可以保持在90％以上.

对台湾肖楠幼苗的移植时间、移植密度等进行对比试验.结果 表明:移植密度对台湾肖楠幼苗移植的保存率影响不显著,而移植时间对保存率有极显著影响,其中4月份移植保存率最高;不同移植时间、移植密度及其两者交互作用下的台湾肖楠幼苗的地径、苗高、全株干生物量、根茎比均存在极显著差异.综合比较台湾肖楠幼苗移植的保存率、地径、苗高、干生物量、根茎比等指标,确定4月份、125株·m-2是台湾肖楠幼苗移植的最佳时问和密度.

[目的]通过探究不同地形下杉木老龄林土壤活性铝形态特征,为杉木人工林生态系统铝毒害的精细化治理提供理论依据.[方法]以福建省南平市百年杉木林为研究对象,测定了该林分西南坡、西北坡、山凹部和山洼地共4类地形土壤的pH值、全铝、交换性铝、单聚体羟基铝、酸溶无机铝和腐殖酸铝含量.[结果]该林分土壤pH值范围为4.72～5.09,活性铝主要形态为腐殖酸铝和酸溶无机铝,其含量占全铝含量的25.52％～60.35％.随着土层深度的增加,土壤铝活化程度逐渐降低,土壤pH值、全铝和腐殖酸铝含量不断增加,交换性铝、单聚体羧基铝和酸溶无机铝含量则不断减少.4类地形土壤pH值总体表现为山洼地>西南坡>山凹部>西北坡,全铝含量表现为山凹部>西北坡>山洼地>西南坡,全铝中活性铝所占比例以及交换性铝和酸溶无机铝含量表现为西北坡>西南坡>山凹部>山洼地,腐殖酸铝含量表现为西北坡>山凹部>西南坡>山洼地,单聚体羧基铝含量表现为山凹部>西南坡>西北坡>山洼地,山洼地土壤各形态活性铝含量普遍显著低于西北坡.地形和土层对于腐殖酸铝的含量具有显著的交互作用.主成分分析表明西南坡和山凹部之间、西北坡和山洼地之间土壤活性铝形态分布较为相似;相关性分析表明土壤pH值与交换性铝、腐殖酸铝和酸溶无机铝含量具有显著负相关关系,交换性铝、酸溶无机铝和腐殖酸铝含量三者间具有显著正相关关系.[结论]该杉木老龄林4类地形中以西北坡土壤活性铝积累现象最为明显,其次为西南坡和山凹部,山洼地最低.

该文对福州市的森林景区进行了调查分析,综合福州各森林景区共有1 835种民族资源植物(95科/473属),可分为25类.建立了福州市民族植物旅游开发优先度评价体系,并以北峰皇帝洞景区为例,对其旅游线路上民族植物评价,排名前3位的为磨芋、石菖蒲、香樟.并且提出了开发途径,为福州民族植物旅游开发提供依据.

Taking the random sampling survey method,the community structure and species composition of community of Bretschneidera sinensis were investigated in Minjiangyuan Nature Reserve,Jianning county,Fujian Province.Results showed that the species composition was complex.There were 39 species belonging to 26 families,34 genera in the community.Shannon-Wienner index was 1.89,Pielou index was 0.33 and Simpson index was 0.52.Bretschneidera sinensis was the dominant species in the community.The concomitant species were abundant,but the relationships among Bretschneidera sinensis and its concomitant species were unstable.

Reinforcement of calcium carbonate on silicone rubber was discussed in detail at particle sizes and surface performance.The reason was analyzed through isotherm of stress-strain and DMAT.It was thought that the mechanism of calcium carbonate composite particles reinforced silicone rubber was not the same as calcium carbonate treated by fatty acid reinforced.The role in silicon membrane and the rubber takes effect mainly between calcium carbonate composite particls and rubber matrix.Calcium carbonate composite particles are suitable for high-modulus structural adhesive because their resistance displacement ability is better than what of others.

<正>气相二氧化硅(俗称气相法白碳黑)是一种白色、无毒、无味、无定形的无机精细化工产品。其原生粒子在7-40纳米,随后原生粒子互相碰撞,熔结成为一体,形成三维和有分支的链状聚集体,聚集体在3- 30微米;其比表面积在70-400m2/g之间。气相二氧