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Effects of Fresh Cupressus sempervirens Leaves Infusion on Growth Performance, Intestinal Microbiota and Haemato-Biochemical Parameters in Broilers
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作者 Donfack Mikael Noumbissi Marie Noël Bertine +7 位作者 Ciemeni Michelle Aimee Tindo Tsamene Romario Evelyn Ngwa Bih Djamen Tchantchou Chamberlin Nyembo Kondo Camile Tsafong Jeatsa Franklain Necdem Tsafack Boris Kana Jean Raphaël 《Open Journal of Animal Sciences》 2024年第2期70-87,共18页
The accumulation of growth-promoting antibiotic residues in animal products and the resistance developed by bacteria in poultry farms has led to a search for natural compounds derived from plants. This study was desig... The accumulation of growth-promoting antibiotic residues in animal products and the resistance developed by bacteria in poultry farms has led to a search for natural compounds derived from plants. This study was designed to promote the production performance of broiler chickens using fresh Cupressus sempervirens leaves infusion. Fresh Cupressus sempervirens leaves were harvested, washed, chopped and ground to a paste using a blender and fermented for three days in a closed container at a rate of 500 g/L of water. The solution obtained was filtered and added at the rate of 2, 4, 6, 8 and 10 ml/L of drinking water. The chickens fed on the graded level of the solution were compared to a control ration without an additive and positive control group supplemented with 1 g antibiotic/kg feed. At the finisher phase and throughout the study period, water intake increased significantly (P < 0.05) with increasing levels of infusion. Feed intake decreased significantly (P < 0.05) with 2 and 4 ml of infusion/L drinking water. Live weight and weight gain were significantly (P < 0.05) higher with 6 ml/L, while feed conversion significantly (P < 0.05) decreased with the same treatment compared with the control treatment without additives (T0). Carcass characteristics were not significantly (P > 0.05) affected by the inclusion of Cupressus sempervirens infusion. Haematological parameters significantly (P < 0.05) increase independently of the rate of incorporation of the infusion into the drinking water, with the exception of RBCs, MCHT and PCT. Serum content in total protein, globulins, LDL cholesterol and triglycerides were significantly (P < 0.05) high with 8 and 10 ml Cupressus sempervirens infusion/litre drinking water as compared to all other treatments. AST, ALT, urea, creatine, albumin, total cholesterol and HDL-cholesterol were not significantly affected. The lactic acid bacteria load increased significantly (P E. coli and salmonella counts decreased significantly (P < 0.05) with infusion compared to the control without additive. In conclusion, 6 ml of Cupressus sempervirens infusion can be used as an alternative to antibiotic feed additives to promote growth performance in broilers. 展开更多
关键词 BROILERS cupressus sempervirens Growth Performance Haemato-Biochemical Parameters Intestinal Microbiota
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水分胁迫对重庆石灰岩地区不同龄级柏木(Cupressus funebris Endl.)幼苗气体交换的影响 被引量:16
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作者 刘锦春 钟章成 何跃军 《生态学报》 CAS CSCD 北大核心 2007年第9期3601-3608,共8页
通过盆栽水分胁迫试验,采用美国Li-COR公司生产的Li-6400便携式光合测定分析仪,对比研究了水分胁迫对重庆石灰岩地区不同龄级柏木幼苗气体交换的影响。结果表明:水分胁迫降低了两种年龄柏木幼苗的净光合速率、蒸腾速率和气孔导度,1年生... 通过盆栽水分胁迫试验,采用美国Li-COR公司生产的Li-6400便携式光合测定分析仪,对比研究了水分胁迫对重庆石灰岩地区不同龄级柏木幼苗气体交换的影响。结果表明:水分胁迫降低了两种年龄柏木幼苗的净光合速率、蒸腾速率和气孔导度,1年生幼苗的净光合速率下降的幅度大于5年生幼苗。1年生幼苗的胞间CO2浓度随着水分胁迫强度的增加而升高,而气孔限制值下降,5年生幼苗在重度干旱前,胞间CO2浓度随着水分胁迫强度的增加而降低,气孔限制值上升,但重度干旱后,趋势与1年生幼苗相同,由这些指标的变化趋势分析得出,1年生幼苗的净光合速率的下降是由非气孔限制因素引起的,而5年生幼苗在重度干旱前净光合速率的下降是由气孔限制因素引起,而在重度干旱后转为非气孔因素。1年生幼苗的水分利用效率随着水分胁迫的加剧而降低,5年生幼苗水分利用效率呈上升趋势,说明5年生幼苗更能适应干旱胁迫。干旱胁迫降低了一年生柏木幼苗的表观量子产额、羧化效率以及最大净光合速率即光合能力,但光补偿点、CO2补偿点、光呼吸和暗呼吸却随着水分胁迫的加剧而升高。对于5年生幼苗,干旱胁迫对其表观量子效率、光补偿点、光呼吸及光合能力的影响基本与一年生幼苗一致。但羧化效率、CO2补偿点呈先降后升的趋势,而暗呼吸却先升后降,说明适度的干旱(未遭受重度干旱之前)提高了柏木的CO2利用能力,但因呼吸消耗较多的光合产物还是导致了其光合能力的降低,但降低的程度较一年生幼苗小,表现为对干旱环境更好的适应能力。 展开更多
关键词 石灰岩 水分胁迫 不同龄级 柏木 气体交换
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中国柏木属(Cupressus L.)植物的petG-trnP序列分析及其系统学意义 被引量:4
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作者 牟林春 王丽 +2 位作者 姚丽 郝冰清 罗勤 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第5期1033-1037,共5页
对中国柏科(Cupressaceae)柏木属(CupressusL.)5个种及扁柏属4个种的cpDNA非编码区petG-trnP序列进行了分析,其片段的长度范围在417bp^479bp之间.以侧柏(Platy-cladus orientalis)作为功能性外类群,运用PAUP*和MEGA软件分别对其进行聚... 对中国柏科(Cupressaceae)柏木属(CupressusL.)5个种及扁柏属4个种的cpDNA非编码区petG-trnP序列进行了分析,其片段的长度范围在417bp^479bp之间.以侧柏(Platy-cladus orientalis)作为功能性外类群,运用PAUP*和MEGA软件分别对其进行聚类分析,应用最大似然法得到一棵最优系统树,其-Ln=2232.47.结果表明:用petG-trnP序列来分析柏木属和扁柏属的系统发育关系是可行的;中国柏木属植物是一个单系类群;Chamaecyparisnootkatensis与扁柏属其它植物关系较远.因此,柏木(Cupressus funebris)和Ch.nootkatensis均应并入柏木属. 展开更多
关键词 柏木 petG—trnP序列 分子系统发育
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柏木(Cupressus funebris Endl.)木材生长与材质变异关系的研究 被引量:3
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作者 杨冬生 唐君畏 《四川农业大学学报》 CSCD 1990年第1期55-60,共6页
采用树干解析,生长锥取样测试、回归分析方法研究了柏木木材生长和材质变异的关系。结果表明柏木木材速生期持续50年以上,初始形成心材的年龄为13—16年,木材最大密度出现在20—25年间。人工林较同龄级天然林分蓄积高11.7%,速生期提早5... 采用树干解析,生长锥取样测试、回归分析方法研究了柏木木材生长和材质变异的关系。结果表明柏木木材速生期持续50年以上,初始形成心材的年龄为13—16年,木材最大密度出现在20—25年间。人工林较同龄级天然林分蓄积高11.7%,速生期提早5—10年,最大密度提早5年。心材量与年龄间呈显著线性相关(r=0.9464),其色泽多型现象被认为是与木材内含物氧化过程有关,而后者受制于年龄和生命活力。 展开更多
关键词 柏木 木材 边材 心材 密度
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柏木(Cupressus funebris Endl)材质、材性要素的宏观生态变异 被引量:3
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作者 唐君畏 杨冬生 《四川农业大学学报》 CSCD 1993年第1期138-144,共7页
在随机抽取木材样件并进行材质材性测定的基础上,通过典型正交分析,研究了柏木材质的宏观生态变异规律。结果表明林型、立地类型、栽培区和经营类型的改变显著地影响到柏木的材质材性要素。与阔叶树种混交显著增大了气干密度、管胞长度... 在随机抽取木材样件并进行材质材性测定的基础上,通过典型正交分析,研究了柏木材质的宏观生态变异规律。结果表明林型、立地类型、栽培区和经营类型的改变显著地影响到柏木的材质材性要素。与阔叶树种混交显著增大了气干密度、管胞长度和年轮宽度,提高了木材抗压,抗弯强度;随着立地的贫瘠化,木材抗压、抗弯强度增大;栽培区和经营类型的改变主要通过调节木材数量生长影响及材质、材性。研究结果为柏木材质定向培育提供了科学的措施依据。 展开更多
关键词 柏木 木材 立地条件类型
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基于生长与木材性状的柏木优良家系选择
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作者 华克达 孙娇娇 +5 位作者 王建昌 楼君 丰忠平 楼科勋 赵浩博 张振 《浙江林业科技》 2024年第3期33-39,共7页
研究达主伐年龄的柏木Cupressus funebris优树子代生长与材性性状的遗传变异规律,可为选育速生优质家系及其推广应用奠定基础。以浙江省淳安县林业总场有限公司姥山分场45个32年生柏木优树子代家系试验林为试材,以淳安当地普通种(CK1)... 研究达主伐年龄的柏木Cupressus funebris优树子代生长与材性性状的遗传变异规律,可为选育速生优质家系及其推广应用奠定基础。以浙江省淳安县林业总场有限公司姥山分场45个32年生柏木优树子代家系试验林为试材,以淳安当地普通种(CK1)和一代种子园优树混合种(CK2)为对照,测定生长性状(树高、胸径和冠幅)、木材基本密度和树干碳含量,分析变异系数,估算遗传力参数及性状间的相关性。结果表明,柏木树高、胸径、木材基本密度和树干碳含量皆存在显著的家系差异,其中单株材积和树干碳含量变异相对较大,而木材基本密度和碳密度的变异较小,变异系数在5%以下;各性状的家系遗传力在0.21~0.63,说明除冠幅外,其余性状受中等程度以上的遗传控制。相关分析结果显示,选择速生家系可同时改良树干碳含量,但对木材基本密度和碳密度影响不大。基于速生优质和高固碳的育种目标,综合选择出5个优良家系,其单株材积、木材基本密度和树干碳分别高出种子园混系种(CK2)97.93%、2.17%和132.36%。 展开更多
关键词 柏木 家系 生长 木材基本密度 碳含量 选择
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Influence of Dowel Center Spacing on Chamfered-Joint Components Made byCupressus funebris Wood
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作者 Jianhua Lyu Jialei Wang +1 位作者 Ziqiang Chen Ming Chen 《Journal of Renewable Materials》 SCIE EI 2023年第1期309-319,共11页
The traditional tenon and mortise joint has low processing efficiency and a weak theoretical basis,making the structure easy to deform and damage,reducing the safety,and increasing waste of resources.This study aims t... The traditional tenon and mortise joint has low processing efficiency and a weak theoretical basis,making the structure easy to deform and damage,reducing the safety,and increasing waste of resources.This study aims to determine the optimum dowel center spacing parameter for chamfered-joint components and the maximum value of the strength of joints loaded into bending strength and tensile strength.In this study,an integrated opti-mization method combining the single-factor test and one-way ANOVA analysis was proposed to study the influ-ence of the dowel center spacing on the bending strength and the tensile strength of chamfered-joint components made by Cupressus funebris wood.The results revealed that the bending strength of chamfered-joint components decreases linearly with the increase of the dowel center spacing.In addition,the tensile strength of chamfered-joint components increases first and then decreases with the increase of the dowel center spacing,showing para-bola change.The relational expression between dowel center spacing,the bending strength,dowel center spacing and the tensile strength were obtained. 展开更多
关键词 Dowel center spacing chamfered-joint bending strength tensile strength cupressus funebris wood
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碳纤维增强复合材料加固柏木轴压裂纹演化规律的研究
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作者 谢玉强 佘艳华 +2 位作者 黄俊杰 李猛 何佳明 《森林工程》 北大核心 2024年第2期102-116,共15页
为研究2层不同角度碳纤维增强复合材料(Carbon Fiber Reinforced Polymer/Plastic, CFRP)加固柏木的受压裂纹演化规律,对分别粘贴2层30°、60°、90°CFRP的柏木进行单轴压缩试验,利用声发射(Acoustic Emission, AE)技术和... 为研究2层不同角度碳纤维增强复合材料(Carbon Fiber Reinforced Polymer/Plastic, CFRP)加固柏木的受压裂纹演化规律,对分别粘贴2层30°、60°、90°CFRP的柏木进行单轴压缩试验,利用声发射(Acoustic Emission, AE)技术和数字图像相关(Digital Image Correlation, DIC)技术对试件的裂纹演化过程进行监测,最后结合数值模拟对试件的荷载位移曲线进行验证并提供加固木材的方法指导。结果表明,声发射信号可以反映试件裂纹的萌生规律及力学特性,CFRP包裹角度越大,试件裂纹扩展越平缓,延性越高,最大承载力越高;RA-AF分析法和DIC表面云图的结合可以反映试件裂纹类型、萌生的位置及扩展过程,试件的裂纹均以张拉型裂纹为主,且CFRP包裹角度越大,裂纹就越容易在端部产生;AE技术、RA-AF分析法、DIC技术和数值模拟的结合为进一步研究CFRP包裹角度与裂纹演化规律的影响关系提供参考。 展开更多
关键词 柏木 CFRP 声发射 数字图像相关技术 数值模拟 裂纹
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雷登柏(Cupressus leighton Green)在胶东地区引种的生态适应性评价
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作者 陈丽英 王淑惠 +6 位作者 张建梅 孙晓慧 赵莹 姚明志 唐明亮 于忠辉 孙太元 《青岛农业大学学报(自然科学版)》 2023年第3期227-231,236,共6页
以胶东地区引进树种雷登柏为研究对象,运用层次分析法构建以生长适应性、抗逆性、观赏性为主要指标的评价体系,对雷登柏进行生态适应性综合评价,以期为雷登柏在胶东地区的引种栽培和开发利用提供理论依据和技术支撑。结果表明:雷登柏的... 以胶东地区引进树种雷登柏为研究对象,运用层次分析法构建以生长适应性、抗逆性、观赏性为主要指标的评价体系,对雷登柏进行生态适应性综合评价,以期为雷登柏在胶东地区的引种栽培和开发利用提供理论依据和技术支撑。结果表明:雷登柏的苗木保存率、年均树高生长量、年均地径生长量、年均冠幅生长量均显著高于本地同科乡土树种侧柏;苗木保存率、年均树高生长量、年均地径生长量均显著高于本地乡土树种黑松;抗涝性显著优于侧柏,抗病虫害能力显著优于黑松;雷登柏四季常绿,冠形优美,分枝匀称,观赏价值较高;雷登柏生态适应性综合评价指数为0.9632,生态适应性强,适宜在胶东地区荒山造林及园林景观绿化中推广应用。 展开更多
关键词 雷登柏 生态适应性评价 胶东地区 层次分析法 引进树种
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废弃矿区不同比例柏木混交林修复效应研究 被引量:1
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作者 李贵 陈瑞 +5 位作者 刘振华 吴敏 童琪 刘森 谢沛源 童方平 《西部林业科学》 CAS 北大核心 2023年第5期55-63,共9页
为研究废弃矿区不同混交比例对柏木混交林林分生长和土壤修复效应的影响,探索最佳柏木混交修复模式,在湖南冷水江市废弃矿区选择5个不同树种组成的植被修复模式:2柏木5楸树3女贞(B2Q5L3)、6柏木4冬青(B6D4)、7柏木3南酸枣(B7N3)、8柏木... 为研究废弃矿区不同混交比例对柏木混交林林分生长和土壤修复效应的影响,探索最佳柏木混交修复模式,在湖南冷水江市废弃矿区选择5个不同树种组成的植被修复模式:2柏木5楸树3女贞(B2Q5L3)、6柏木4冬青(B6D4)、7柏木3南酸枣(B7N3)、8柏木2梓树(B8Z2)、柏木纯林(B10),以柏木纯林模式作为对照,对各模式林地土壤质量指标及柏木生长指标进行测定和分析。结果显示:(1)5个模式间柏木生长具有显著差异,除B2Q5L3模式外,其它3种混交模式的柏木平均胸径均显著大于B10模式;4个混交模式的柏木平均树高均显著大于B10模式。(2)5个模式的柏木其根、枝、叶的As、Cd、Sb含量均存在显著差异,柏木器官内As、Sb含量分布规律为叶>枝>根;B10、B8Z2模式除外,其它模式Cd含量分布规律为枝>叶>根。各模式的柏木其根、枝、叶Pb含量高低没有明显的规律。(3)柏木纯林的碱解氮、有效磷、速效钾及有机质含量均显著小于其它4个混交模式,4个混交模式的土壤酶活性大于柏木纯林。(4)5个植物修复模式土壤质量综合得分排序为B8Z2>B6D4>B7N3>B2Q5L3>B10。研究结果表明:相对于柏木纯林,柏木与阔叶树混交有利于柏木的生长;柏木与阔叶树混交后,林地土壤质量得到一定程度的改善,尤其是土壤有效养分和土壤酶活性方面得到显著提高,对矿区土壤的改良及修复效应均优于柏木纯林,而土壤重金属含量的变化没有明显规律。研究结果可为矿区柏木生态修复造林实际应用提供理论依据。 展开更多
关键词 废弃矿区 柏木 混交林 林分生长 植物修复
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施氮对干旱河谷岷江柏(Cupressus chengiana)幼苗光合生理特征的影响 被引量:5
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作者 冯秋红 缪国辉 +3 位作者 徐峥静茹 史作民 缪宁 李登峰 《西南农业学报》 CSCD 北大核心 2020年第7期1455-1460,共6页
【目的】氮素是植物生长发育的重要元素之一。氮添加对植物生理特征影响研究一直是生理生态学研究的重要内容,尤其是在干旱地区。【方法】以2年生岷江柏(Cupressus chengiana)幼苗为研究对象,通过盆栽试验法研究不同程度施氮(N0:不施氮... 【目的】氮素是植物生长发育的重要元素之一。氮添加对植物生理特征影响研究一直是生理生态学研究的重要内容,尤其是在干旱地区。【方法】以2年生岷江柏(Cupressus chengiana)幼苗为研究对象,通过盆栽试验法研究不同程度施氮(N0:不施氮肥,N1:含氮0.75 mg·cm^-3,N2:含氮1.50 mg·cm^-3,N3:含氮2.25 mg·cm^-3)对岷江柏幼苗光合生理特征的影响,探讨岷江柏幼苗的养分、光合生理特征随施氮梯度的响应规律。【结果】施氮能显著提高岷江柏幼苗根茎氮含量和叶片氮磷比,降低叶片磷含量;净光合速率(A)和蒸腾速率(T)均随着施氮量的增加呈现先增加后减少的趋势;PSII实际光化学效率(ΦPSII)、电子传递效率(ETR)则随施氮量的增加而逐渐升高。【结论】对干旱地区岷江柏而言,适量施氮(最大不超过0.75 mg·cm^-3)可以促进其生长,随着施氮量的增加,植物抗旱能力升高,并以降低光合生长为代价。 展开更多
关键词 施氮 岷江柏 光合生理特征 干旱河谷
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林分密度对柏木人工林土壤养分及酶活性的影响 被引量:1
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作者 徐华丽 林虎 +4 位作者 刘小宇 汪洋 蔡京勇 周忠诚 杨旭 《湖南生态科学学报》 CAS 2023年第1期68-74,共7页
【目的】探索不同密度柏木(Cupressus funebris)人工林土壤养分含量及酶活性的变化趋势及其特征。【方法】以35~55年生柏木人工林为对象,研究不同林分密度(密度分别为4160、992、452株/公顷)下0~40 cm土层的土壤养分含量及酶活性变化。... 【目的】探索不同密度柏木(Cupressus funebris)人工林土壤养分含量及酶活性的变化趋势及其特征。【方法】以35~55年生柏木人工林为对象,研究不同林分密度(密度分别为4160、992、452株/公顷)下0~40 cm土层的土壤养分含量及酶活性变化。【结果】柏木人工林土壤养分含量及酶活性均随土层深度的增加呈降低趋势,具有明显的表聚现象。随着林分密度的降低,土壤养分含量呈先降低后增加的趋势,土壤全氮、全磷、全钾、碱解氮、速效钾在452株/公顷林分密度下含量最高;磷酸酶和蔗糖酶活性整体呈增加的趋势,且在452株/公顷林分密度下活性最大。相关分析结果显示:蔗糖酶、磷酸酶与土壤养分指标关系密切。【结论】适宜的林分密度有利于柏木人工林土壤养分的积累,能有效提高土壤肥力。 展开更多
关键词 柏木人工林 林分密度 土壤养分 酶活性
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Breaking seed dormancy in Cupressus atlantica Gaussen,an endemicand threatened coniferous tree in Morocco 被引量:3
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作者 Sfairi Youssef Ouahmane Lahcen Abbad Abdelaziz 《Journal of Forestry Research》 CAS CSCD 2012年第3期385-390,共6页
Cupressus atlantica Gaussen (Cupressaceae) is an endemic and endangered coniferous tree geographically restricted to the N'Fis valley in South-Western Morocco. Like many forest species, C. atlantica exhibits dorman... Cupressus atlantica Gaussen (Cupressaceae) is an endemic and endangered coniferous tree geographically restricted to the N'Fis valley in South-Western Morocco. Like many forest species, C. atlantica exhibits dormancy which delays and reduces germination. To improve seed germination, different pre-treatments were conducted on C. atlantica seeds after storage for different periods (one, two and five years) including: scarification with sandy paper; soaking seeds in hot distilled water at 60℃ and 80℃ for 15 min and soaking seeds for 48 h in a gibberellic acid (GA3) at 1,000 and 2,000 mg·L-1. Results showed that scarification with sandy paper increased the germination rate of Atlas cypress by up to 67%, indicating that the species possess essentially an exogenous dormancy (physical dormancy) due to the hard seed coat (hardseededness). Exogenous application of gibberellic acid (GA3) at 1,000 mg.L-1 was also effective in breaking seed dormancy and germination induction. These two treatments induced faster speed germination expressed by low number of days to first germination (8-10 days) and low values of mean germination times (MGT). However, germination rate, under any treatment, is greatly dependent on the year of seed collection. Seeds collected in year 2004 gave the highest value, suggesting that even after five years of storage, the germination capacity of C. atlantica seeds could remain high. This observation is very interesting in the ex-situ conservation of such endemic and endangered species where the production of seeds is irregular over the years. 展开更多
关键词 cupressus atlantica ENDEMIC ENDANGERED breaking seed dormancy germination capacity hand scarification ex-situ conservation
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Status of cypress aphid on Cupressus lusitanica and Juniperus procera in protected and cultivated forests of South Wollo,Ethiopia 被引量:1
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作者 Asmare Dejen Demeke 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第1期333-337,共5页
In Ethiopia,Cupressus lusitanica and Juniperus procera are important tree species.The incidence of the cypress aphid,Cinara cupressi,which has not been reported before on the exotic Cupressus lusitanica is becoming ca... In Ethiopia,Cupressus lusitanica and Juniperus procera are important tree species.The incidence of the cypress aphid,Cinara cupressi,which has not been reported before on the exotic Cupressus lusitanica is becoming catastrophic.The appearance of the insect was reported for the first time in 2003 in Ethiopia.However,information is scarce on the status of this species in northeast Amhara state.The objectives of this study were to assess the extent of damage,abundance and status of the cypress aphid on C.lusitanica and J.procera in the protected and cultivated forests of South Wollo,Ethiopia.Results reveal that tree compositions of the three study areas differed.The dominant tree species were C.lucitanica(15–80%),Olea europaea(5–90%)and J.procera(14–70%).The cypress aphid showed significantly higher levels of infestation on C.lusitanica(35–90%)than on J.procera(1–16%).Moreover,there was higher C.lusitanica mortality(40–93%).In contrast,there was low infestation(1–16%)on J.procera and no mortality.The results reveal that the cypress aphid causes enormous losses of C.lusitanica.Therefore,it is recommended that insect surveillance be strengthened and the introduction bioagents be considered and integrated with other insecticides to minimize the degree of C.lusitanica infestation and loss. 展开更多
关键词 APHIDIDAE cupressus lusitanica Cinara cupressi Juniperus procera
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林分密度对云顶山柏木人工林林下物种多样性和生物量的影响 被引量:1
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作者 陈波兰 吴雨茹 +5 位作者 钟欣艺 许银 陈辉琴 唐岚 白一术 郝建锋 《四川农业大学学报》 CSCD 北大核心 2023年第4期665-672,共8页
【目的】为探究林分密度对林下植被物种多样性和生物量的影响及二者之间的相关性。【方法】采用典型样地法对四川省金堂县云顶山5种不同林分密度(500、650、800、950、1100株/hm^(2))的柏木(Cupressusfunebris)人工林进行植被调查,统计... 【目的】为探究林分密度对林下植被物种多样性和生物量的影响及二者之间的相关性。【方法】采用典型样地法对四川省金堂县云顶山5种不同林分密度(500、650、800、950、1100株/hm^(2))的柏木(Cupressusfunebris)人工林进行植被调查,统计林下物种多样性和生物量。【结果】共记录植物172种,隶属于78科137属。随着林分密度增大,灌木层多样性指数均呈先增后减的单峰变化,基本在密度650株/hm^(2)达到最大,草本层多样性指数则多呈先增后减再增再减的双峰变化,在密度650株/hm^(2)和950株/hm^(2)出现峰值。灌木、草本层生物量均在密度650株/hm^(2)达到最大且均有地上生物量大于地下生物量。灌木层物种重要值与其各层生物量和草本层地上、全株生物量均呈极显著正相关,草本层物种重要值与其地上、全株生物量均呈极显著正相关。【结论】研究认为该地柏木人工林可在650株/hm^(2)的密度下维持较高的林下植被物种多样性和生物量,利于其林下植被的健康发展。 展开更多
关键词 林分密度 柏木人工林 林下植被 物种多样性 生物量
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Evaluation of Soil Fertility Under Different Cupressus chengiana Forests Using Multivariate Approach 被引量:8
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作者 PANG Xue-Yong BAO Wei-Kai ZHANG Yong-Mei 《Pedosphere》 SCIE CAS CSCD 2006年第5期602-615,共14页
The distribution and growing conditions of Cupressus chengiana forests along with the physical and chemical properties of soils in Northwest Sichuan were studied in 2002 to investigate the conditions and characteristi... The distribution and growing conditions of Cupressus chengiana forests along with the physical and chemical properties of soils in Northwest Sichuan were studied in 2002 to investigate the conditions and characteristics of soil fertility of C. chengiana and to compare and investigate differences of soil fertility for six C. chengiana populations and their relationships with vegetation, climate and disturbance. The results of the study at 0-20 cm soil depth showed that 1) significant differences (P < 0.05) existed among populations for soil bulk density, soil total porosity, capillary porosity, maximum water-holding capacity, capillary water-holding capacity and topsoil natural water content; 2) chemical characteristics of soil organic matter, total N, total P, alkali-hydrolyzable N, available P, available K and cation exchange capacity were significantly different among the populations; and 3) based on the significant effect of soil fertility factors on forest growth, soil physical and chemical characteristics could be selected as an integrated fertility index (IFI) for evaluation of different C. chengiana populations. Principal component and cluster analyses showed significant differences probably due to the difference of vegetation conditions, management measurements, human-induced disturbances and environmental factors. In order to protect the soil ecological functions in fragile ecological regions, C. chengiana could be used in programs enclosing the hill for natural afforestation, natural forest protection programs, and programs replacing agriculture with afforestation measures. 展开更多
关键词 土壤肥力 物理性质 化学性质 四川
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柏木无性系和家系含碳量的早期评价与优良品系选择
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作者 杨涛 邱勇斌 +5 位作者 沈汉 郑成忠 张振 王文月 金国庆 周志春 《林业科学》 EI CAS CSCD 北大核心 2023年第9期85-94,共10页
【目的】探究柏木无性系和家系的早期生长和固碳潜力,为速生高固碳柏木优良品系选择及其推广应用奠定理论基础。【方法】以营建在浙江省开化县林场9年生无性系和家系试验测定林为研究对象,分析其生长性状变异规律,解析各器官生物量和含... 【目的】探究柏木无性系和家系的早期生长和固碳潜力,为速生高固碳柏木优良品系选择及其推广应用奠定理论基础。【方法】以营建在浙江省开化县林场9年生无性系和家系试验测定林为研究对象,分析其生长性状变异规律,解析各器官生物量和含碳量的分配差异,构建含碳量异速生长方程,并对其固碳潜力进行分析和估测。【结果】柏木无性系的平均树高、胸径和单株材积分别高出家系水平47.81%、28.39%和120.83%;树高、胸径和单株材积在无性系间和家系间均存在极显著差异(P<0.01),无论家系还是无性系水平,胸径和树高均与生物量、含碳量呈显著正相关,与含碳率无显著线性关系。柏木树干生物量的分配比例最高,含碳量占比最大,而叶的含碳率最高;无性系主要是以牺牲粗根的生物量分配(较家系低3.45%)、增加树枝生物量(较家系高5.55%)和细根生物量(较家系高1.34%)来维持生长优势。以树高、胸径和枝下高为自变量,拟合的含碳量移速生长方程(lnTBS=k_(0)+k_(1)lnD+k_(2)lnH+k_(3)lnUBH)预测效果最好(除无性系树根含碳量外),将枝下高作为自变量包含在模型中可提高估算精度。按照20%入选率,估算无性系试验林含碳量的遗传增益达51.48%,家系试验林为16.14%,结合材积性状筛选出速生、固碳兼优的无性系和家系各6个。【结论】柏木无性系生长优势明显,相比家系具有更高的固碳能力。在生长早期,考虑将枝下高作为重要评价指标构建含碳量异速生长方程,有助于提高植株含碳量估算精度,结合生长性状可筛选出速生、含碳量高的无性系和家系,提高柏木固碳潜力。 展开更多
关键词 柏木 无性系 家系 生长变异 生物量 含碳量 异速生长方程
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Seasonal Changes in Copper and Cobalt Concentrations of PinusnigraL.,Cedrus libani and Cupressus arizonica Leaves to Monitor the Effects of Pollution in Elazig (Turkey)
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作者 Nagihan M Karaaslan Mehmet Yaman 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2013年第5期1331-1337,共7页
The aim of this study is to examine seasonal changes in Cu and Co concentrations of three plant species for monitoring the effects of pollution in Elazig,Turkey.For this purpose,the leaves of the Pinus nigra L.,Cedrus... The aim of this study is to examine seasonal changes in Cu and Co concentrations of three plant species for monitoring the effects of pollution in Elazig,Turkey.For this purpose,the leaves of the Pinus nigra L.,Cedrus libani and Cupressus arizonica together with soil samples were collected from different points depending on traffic intensity,nearness the city center and cement factory as well as control location during different months of the year.Flame atomic absorption spectrophotometer(FAAS) was used for measurement of the metals in clear digests after the dry ashing method.Copper and Co concentrations were in the ranges from 1.3to 2.6mg.kg-1 and<LOD to 0.26mg.kg-1 for Pinus nigra L.,1.2to 4.7mg.kg-1 and<LOD to 0.41mg.kg-1 for Cedrus libani and 1.5to 4.8mg.kg-1 and<LOD to 0.42mg.kg-1 for Cupressus arizonica,respectively.The levels observed for Cu and Co in the soil ranged from 12to 38mg.kg-1 and 6.0to 17mg.kg-1,respectively. 展开更多
关键词 COPPER COBALT BIOMONITOR Pinus nigra L. Cedrus libani cupressus arizonica
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Growth Performance of Cypress (Cupressus funebris) Trees in Progeny Test Plantations
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作者 Angui DENG Yong PENG +6 位作者 Xiaomei TAN Wendong ZENG Yujun LUO Changwan TAN Yanting LIU Zhengyan LIU Chenyang WANG 《Agricultural Biotechnology》 CAS 2019年第2期96-100,共5页
Based on the 6-year-old young forests of 40 cypress(Cupressus funebris) families from four provenances(Fengdu County, Youyang County and Zhong County of Chongqing City, and Qiandao Lake in Zhejiang Province), differen... Based on the 6-year-old young forests of 40 cypress(Cupressus funebris) families from four provenances(Fengdu County, Youyang County and Zhong County of Chongqing City, and Qiandao Lake in Zhejiang Province), differences in growth traits between families and provenances were studied to select excellent families, so as to provide necessary data support for the upgrading of cypress seed gardens and inferior thinning of seed gardens. The results showed that there were significant differences in tree height, diameter at one meter height, crown width and growth potential between families and provenances. The coefficients of variation among families were 10.25%, 7.19%, 5.91% and 0.98%, respectively, and the coefficients of variation in tree height and diameter at one meter height among provenances were 7.25% and 12.58%, respectively, indicating that the tree height and diameter at one meter height of the superior cypress tree families were rich in variation among families and provenances, and there was potential for high-generation breeding. According to the selection rate of 15%, six excellent families for afforestation(Feng 8, Shi 4, Feng 1, Ye 14, Shi 3, and Ye 6) were screened. The average diameter at one meter height, tree height and crown width of the six excellent families were, respectively, 2.97 cm, 3.39 and 0.78 m, which were 18.82%, 12.70% and 15.42% higher than the family average, respectively, and 15.09%, 9.79% and 15.53% higher than the control group, respectively. 展开更多
关键词 cupressus funebris PROGENY test FAMILY Variation EARLY selection
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Protective role of Juniperus phoenicea and Cupressus sempervirens against CCl_4
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作者 Sanaa Ahmed Ali Maha Zaki Rizk +3 位作者 Nabawia Ali Ibrahim Mohga Shafik Abdallah Hayat Mohamed Sharara Magda Mohamed Moustafa 《World Journal of Gastrointestinal Pharmacology and Therapeutics》 CAS 2010年第6期123-131,共9页
AIM: To investigate the role of Cupressus sempervirens (C. sempervirens) and Juniperus phoenicea (J. phoe-nicea) extracts as therapeutic effect against CCl4 with biochemical, histopathological evaluations. METHODS: A ... AIM: To investigate the role of Cupressus sempervirens (C. sempervirens) and Juniperus phoenicea (J. phoe-nicea) extracts as therapeutic effect against CCl4 with biochemical, histopathological evaluations. METHODS: A single intraperitoneal dose of 10% CCl4 in olive oil (1 mL/kg body weight) was administered to a group of female Wister rats, sacrificed after 24 h (as the injury group). The other groups were given CCl4 as de-scribed above and divided as follows: two groups of ten rats each were orally administered either J. phoenicea extract or C. sempervirens extract three times per week for six weeks and a further group administered CCl4 was left for six weeks to allow self-recovery. At the end of experiment, the rats from all groups were sacrificed for sampling and for biochemical and histological analysis. RESULTS: Remarkable disturbances were observed in the levels of all tested parameters. On the other hand,rats injected with the toxic agent and left for one and a half month to self recover showed moderate improve-ments in the studied parameters while, treatment with both medicinal herbal extracts ameliorated the levels of the disturbed biochemical parameters. The group treated with J. phoenicea extract showed a remarkable improvement in comparison to the CCl4 treated group. The C. sempervirens group revealing an even more re-markable effect showing histopathological liver& kidney profiles close to those of the control group.CONCLUSION: C. sempervirens and J. phoenicea leaf extracts show a remarkable effect in enhancing liver and kidney functions and may thus be of therapeutic potential in treatment hepatotoxicity and nephrotoxicity. 展开更多
关键词 cupressus sempervirens JUNIPERUS phoeni-cea Carbon TETRACHLORIDE HEPATOTOXICITY NEPHROTOXICITY
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