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Growth and Influencing Factors of Three Native Tree Species in Coastal Casuarina equisetifolia Plantation
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作者 姚宝琪 刘强 +1 位作者 蔡梓 王孝杉 《Agricultural Science & Technology》 CAS 2011年第2期228-232,共5页
[Objective] The aim was to study the growth and environment factors of three native tree species(Thespesia lampas,Calophyllum inophyllum and Hernandia sonora)in Hainan in coastal Casuarina equisetifolia plantation.[... [Objective] The aim was to study the growth and environment factors of three native tree species(Thespesia lampas,Calophyllum inophyllum and Hernandia sonora)in Hainan in coastal Casuarina equisetifolia plantation.[Method] The coastal sandy soil was treated by adding wood chips,bagasse and the control without adding anything in the plant pits.The growth of three native tree species planted for one year was analyzed.[Result] ① One year later,the survival rate showed an order of T.lampasH.sonoraC.inophyllum;the net increase of basal diameter showed an order of H.sonoraT.lampasC.inophyllum;while the net increase of plant height showed an order of T.lampasC.inophyllumH.sonora.The difference of survival rate between T.lampas and C.inophyllum was extremely significant,the difference of survival rate between H.sonora and C.inophyllum was significant,but the survival rate between T.lampas and H.sonora showed no significant difference.The difference on net growth of plant height among T.lampas,C.inophyllum and H.sonora was extremely significant,and the different on the net growth of basal diameter between T.lampas and C.inophyllum was significant.② Among different soil treatments,the survival rate of three native tree species in the treatment by adding wood chips,bagasse were higher than the treatment without adding anything,and the difference of survival rate of T.lampas between the treatment by adding wood chips,bagasse and the treatment without adding anything was extremely significant,but the treatment by adding wood chips and bagasse had not significant difference.③ The growth of three native tree species showed some correlation with environment factors(∣r∣0.3).The survival rate of T.lampas showed higher correlation with soil pH value and soil moisture,and the basal diameter and height of T.lampas showed some correlation with soil pH value and soil temperature.The survival rate of C.inophyllum showed higher correlation with soil pH value,soil temperature and light intensity,while the basal diameter and height of C.inophyllum showed some correlation with soil temperature.The survival rate of H.sonora showed higher correlation with soil salinity and soil temperature,while the basal diameter and height of H.sonora showed some correlation with soil temperature.The basal diameter and height of three native tree species had higher correlation(r0.5),which had reached a significant level.[Conclusion] In the one-year growth period in C.equisetifolia forest,the native tree species of T.lampas grew best and it was the most potential forest species mixed with C.equisetifolia. 展开更多
关键词 native tree species GROWTH Environment factors
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Responses of Native Tree Species to Soil Water Stress in a Tropical Forest on Limestone,Vietnam 被引量:2
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作者 Le Van Binh Nguyen Van Thinh +2 位作者 Reinhard Kopp Vo Dai Hai Ralph Mitlohner 《Open Journal of Forestry》 2015年第7期711-722,共12页
Forests over limestone in the tropics have received little attention and limestone forests in Vietnam have been overlooked to an even greater extent in terms of tree physiology. In Ba Be National Park, Vietnam, soil w... Forests over limestone in the tropics have received little attention and limestone forests in Vietnam have been overlooked to an even greater extent in terms of tree physiology. In Ba Be National Park, Vietnam, soil water availability in limestone forests seems to be the most limiting factor in the dry season. Therefore, in order to enhance the preliminary knowledge of choosing native tree species for enrichment planting in the restoration zone, characteristics of the 20 native tree species to soil water stress were investigated in a limestone forest. One-ha plot each consisting of twenty-five 20 m × 20 m plots was established in undisturbed forests. All trees ≥ 10 cm DBH were measured in 20 m × 20 m plots, while twenty-five 5 m × 5 m subplots were established in order to sample the regeneration of tree species with a DBH < 10 cm. The Scholander apparatus and freezing point osmometry were used in order to measure the leaf water potential (Ψw) and leaf osmotic potential (Ψπ) of the 20 native tree species, respectively in this study. 61 species belonging to 34 families of all trees with a DBH ≥ 10 cm were recorded in one ha, while 31 species representing 18 families of trees < 10 cm DBH were identified in 625 m2. The 20 species’ leaf water and osmotic potential values revealed significant differences among species. The maximum leaf water potential was not affected by any anticipated sources of variation, while the minimum water potential, however, showed significant variation to soil water stress. The results in the study area emphasized the importance of water factors in influencing tree species distribution;it could be concluded that native species with wide water potential ranges would be better able to withstand water changes and might be thus good candidates for reforestation (enrichment planting) in limestone areas. 展开更多
关键词 Tropical Limestone Forests Floristic Composition native tree Species Leaf Water Potential Leaf Osmotic Potential
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Propagation of Grevillea banksfi Affects the Dynamic of Mycorrhizal Fungi Communities Associated with Native Tree Species of Madagascar
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作者 Martial Doret Andrianandrasana Rondro Harinisainana Baohanta +4 位作者 Herizo Randriambanona Marson Raherimandimby Damase Khasa Robin Duponnois Heriniaina Ramanankierana 《Journal of Life Sciences》 2014年第6期511-516,共6页
Propagation of exotic plant species is found in many regions of Madagascar Island. This work aims to describe the impacts of the propagation of Grevillea banksii on soil microbial activities and on the regeneration of... Propagation of exotic plant species is found in many regions of Madagascar Island. This work aims to describe the impacts of the propagation of Grevillea banksii on soil microbial activities and on the regeneration of two native tree species (Intsia bij'uga and Dalbergia trichocarpa) in the eastern part of Madagascar. The study was conducted within Ianjomara forest where some types of the vegetation are observed such as an area characterized by grassland (P 1), by homogeneous population of G. banksii (P2) and by a natural forest composed mainly of L bijuga or D. trichocarpa (P3 and P4). Structure of mycorrhizal fungi communities and associated microorganisms were described on soils from each study plot. The development of I. b^juga and 1). trichocarpa, was evaluated 4 months after planting on P1, P2, P3, P4 soils formerly colonized by G. banksii. According to the nutrients availability on each soil type, the development of G. banksii was accompanied or not by a high formation of cluster roots. The authors' results also show that soil occupied by G. banksii decreased the global microbial and phosphatase activities of soil especially on soil within a high density of cluster roots. Moderately mycotrophic, G. banksii disturbs the structure and the dynamics of symbiotic microflora such as endomycorrhizal fungi (MA) and rhizobia associated with the two native tree species. The findings illustrate the negative impact of G. banksii propagation on the regeneration and the conservation of native tree species in Madagascarian forest. 展开更多
关键词 Grevillea banksii invasive plant microbial community native tree species cluster roots.
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一种基于二叉树的Native XML数据库文档编码机制 被引量:3
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作者 张鹏 冯建华 房志峰 《计算机应用》 CSCD 北大核心 2008年第9期2331-2334,共4页
在对于现有编码机制进行综述的前提下,提出一种新的XML文档编码机制,该编码机制基于完全二叉树的结构顺序编码。在该XML文档编码机制下,判断节点之间祖先-后裔关系算法的时间复杂度仅为O(logn),完全支持更新,并且编码长度较短。
关键词 native XML数据库 编码机制 XML查询 完全二叉树
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利用Windows Native API调用序列和基于决策树算法的主机异常检测 被引量:2
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作者 李乃捷 彭勤科 《计算机应用研究》 CSCD 北大核心 2007年第1期258-260,共3页
主要研究W indows平台下的异常检测方法,提出一种利用W indows Native API调用序列和基于决策树算法的主机服务进程模式抽取算法,并通过在模式中引入通配符而大大缩减了模式集的规模。进一步引入了表征模式间关系的转移概率,建立了模式... 主要研究W indows平台下的异常检测方法,提出一种利用W indows Native API调用序列和基于决策树算法的主机服务进程模式抽取算法,并通过在模式中引入通配符而大大缩减了模式集的规模。进一步引入了表征模式间关系的转移概率,建立了模式序列的全局马尔可夫链模型,并给出了相应的异常检测算法。实验结果表明:该算法可以抽取一个规模较小且泛化能力较强的模式集,相应的检测算法可以有效地检测异常。 展开更多
关键词 主机异常检测 WINDOWS native API 决策树 间断模式
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Native XML数据库——dbXML的存储策略的改进
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作者 王汉林 谢荣传 《计算机与现代化》 2008年第7期26-28,32,共4页
Native XML数据库是当前数据库领域的研究热点之一。XML文档在Native XML数据库中的存储和索引策略是首要关心的问题。本文以一个开放源代码的Native XML数据库产品—dbXML为对象,分析了它的页面存储策略;然后,针对其页面存储策略在&qu... Native XML数据库是当前数据库领域的研究热点之一。XML文档在Native XML数据库中的存储和索引策略是首要关心的问题。本文以一个开放源代码的Native XML数据库产品—dbXML为对象,分析了它的页面存储策略;然后,针对其页面存储策略在"空闲"页面管理上存在的不足,提出并实现了新的策略,有效地释放了"空闲"页面占用的磁盘空间,提高了系统对磁盘资源的利用率。 展开更多
关键词 native XML数据库 存储策略 B+树
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干旱胁迫对胡杨、沙枣幼苗的生理影响
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作者 郝瑜 张茜 +2 位作者 马赵群 王海珍 韩路 《东北林业大学学报》 CAS 北大核心 2025年第2期43-51,共9页
筛选高抗逆树种并优化防护林树种配置是解决极端干旱区农田防护林大面积顶梢干枯、衰败的有效途径。以塔里木荒漠乡土树种胡杨、沙枣幼苗为试验材料,采用盆栽控水法研究两树种幼苗抗氧化酶活性、渗透调节物质对干旱胁迫程度、胁迫时间... 筛选高抗逆树种并优化防护林树种配置是解决极端干旱区农田防护林大面积顶梢干枯、衰败的有效途径。以塔里木荒漠乡土树种胡杨、沙枣幼苗为试验材料,采用盆栽控水法研究两树种幼苗抗氧化酶活性、渗透调节物质对干旱胁迫程度、胁迫时间的动态响应及抗旱性差异。结果表明:(1)随干旱胁迫程度加剧与胁迫时间延长,胡杨、沙枣叶游离脯氨酸(Pro)质量分数、可溶性蛋白(SP)质量分数、丙二醛(MDA)质量摩尔浓度、叶饱和亏缺及胡杨叶超氧化物歧化酶(SOD)活性均呈增加趋势;两树种幼苗叶过氧化物歧化酶(POD)活性、叶相对含水量呈降低趋势。(2)随干旱胁迫程度加剧,沙枣叶Pro、SP质量分数显著高于胡杨,胡杨叶SOD活性高于沙枣,POD活性相反。胡杨、沙枣幼苗均以Pro、SP维持叶细胞渗透压,并通过SOD清除活性氧(ROS)来协同适应干旱胁迫。(3)综合分析表明沙枣幼苗的抗旱能力优于胡杨幼苗。建议干旱区绿洲农田防护林建设中优先选择沙枣或以沙枣、胡杨为主要树种营建混交林,以及退化防护林改造修复时配置补植沙枣,恢复农田防护林的生态功能。 展开更多
关键词 抗旱性 渗透调节物质 保护酶 乡土树种
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Optimized XML Storage in NXD Based on Tree-Structure Disassemble
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作者 LIU Yun-sheng WANG Yi ZHONG Hao 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期93-99,共7页
Independent XML storage based on XSD (XML Schema Document) is adopted in NXD(Native XML Data base), XMI. storage structure based on tree-structure disassemble and the algorithm used in dynamically updating XML doc... Independent XML storage based on XSD (XML Schema Document) is adopted in NXD(Native XML Data base), XMI. storage structure based on tree-structure disassemble and the algorithm used in dynamically updating XML document are provided in this paper. The main idea is that in term of data model of XML document, XML document is parsed to Document Structure-Tree with Hierarchical Model and Leaf-Data with Relation Model for storage. Simultaneously Proxy node is imported in order to solve the problem that XML data store in cross-blocks. And with XSD model information, sparse index is constructed to save storage space. It is proved that this storage structure could improve efficiency of XML document operation. 展开更多
关键词 XML storage storage model NXD native XML database) document trees regular expression
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海南热带海岸海防林植被恢复的探索与实践 被引量:1
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作者 刘强 《热带林业》 2024年第1期108-113,103,共7页
文章分析了海南岛热带海岸存在植被生态退化问题,针对主要的退化问题钛锆砂矿废弃地的植被退化和单一树种的人工木麻黄海防林的缺陷,提出了分三步走恢复海岸海防林植被的学术思路,即恢复和巩固木麻黄海防林;建立引入乡土树种的混交林型... 文章分析了海南岛热带海岸存在植被生态退化问题,针对主要的退化问题钛锆砂矿废弃地的植被退化和单一树种的人工木麻黄海防林的缺陷,提出了分三步走恢复海岸海防林植被的学术思路,即恢复和巩固木麻黄海防林;建立引入乡土树种的混交林型海防林;促进混交林演替成具地带性植被特征的天然林型海防林。按照这个思路开展了近20年的海岸植被生态恢复的实证研究和应用实践,验证了其可行性,实现了初步构建乡土林型的海防林植被,达到了研究构想预期的效果。研究成果为海南岛以及华南沿海热带海岸的海防林生态恢复提供了可借鉴的范例。 展开更多
关键词 热带海岸 海防林 生态退化 乡土树种 植被恢复
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基于客户消费习惯的贝叶斯网络的分类算法
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作者 吕金锐 《软件》 2024年第4期104-106,共3页
面对大量用户的通信消费数据,如何对其进行挖掘从而获得有价值的信息,对客户进行分类,并制定不同的服务策略,是当前通信企业面临的一个普遍问题。本文介绍了几种常用的文本分类算法,通过分析用户的消费行为数据,选取了朴素贝叶斯分类预... 面对大量用户的通信消费数据,如何对其进行挖掘从而获得有价值的信息,对客户进行分类,并制定不同的服务策略,是当前通信企业面临的一个普遍问题。本文介绍了几种常用的文本分类算法,通过分析用户的消费行为数据,选取了朴素贝叶斯分类预测算法、贝叶斯网络分类预测算法和决策树分类预测算法对用户进行分类,实验结果表明贝叶斯网络分类预测算法对于用户通信消费数据具有较好的分类效果。 展开更多
关键词 文本分类 朴素贝叶斯 贝叶斯网络 决策树
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我国南亚热带乡土珍贵树种人工幼林不同器官营养元素储量及分配特征
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作者 谭长强 申文辉 +2 位作者 郑威 黄志玲 徐大平 《东北林业大学学报》 CAS CSCD 北大核心 2024年第11期31-39,共9页
为了阐明我国南亚热带主要乡土珍贵阔叶造林树种营养元素储量及分配特征,以广西9年生的主要乡土珍贵树种红锥(Castanopsis hystrix)、火力楠(Michelia macclurei)、格木(Erythrophleum fordii)、荷木(Schima superba)、蚬木(Excentroden... 为了阐明我国南亚热带主要乡土珍贵阔叶造林树种营养元素储量及分配特征,以广西9年生的主要乡土珍贵树种红锥(Castanopsis hystrix)、火力楠(Michelia macclurei)、格木(Erythrophleum fordii)、荷木(Schima superba)、蚬木(Excentrodendron tonkinense)、西南桦(Betula alnoides)、任豆(Zenia insignis)、降香黄檀(Dalbergia odorifera)和柚木(Tectona grandis)为试验对象,分析8种营养元素(N、P、K、Ca、Mg、Fe、Zn、Mn)在各树种的储量及分配特征。结果表明:9个树种单株营养元素总储量存在显著差异(P<0.05),由大到小顺序为:火力楠、红锥、荷木、柚木、降香黄檀、蚬木、西南桦、格木、任豆,不同树种不同器官之间、不同元素储量之间也存在显著差异(P<0.05)。不同营养元素在9个树种中储量占总储量的比例不同,所有树种排位前三的均为N、K、Ca,占总元素储量比例的85.5%~93.1%。9个树种由于自身的生理特性,对元素的需求和积累能力存在差异,其中,荷木及火力楠对Mn元素的吸收固定能力较强;蚬木对N、Mg、Fe、Zn、Mn营养元素的积累能力较低;降香黄檀对P、Zn、Mn的积累能力较低;格木对K、Ca的积累能力较低。9个树种对N、P、K、Ca、Mg、Zn、Mn营养元素的积累总体表现了茎最大,对Fe元素的存储主要集中于茎和根。9个树种每生产1 t干物质所需营养元素为8.08~25.23 kg,树种的营养总利用效率主要受树种生长特性的影响,速生树种营养利用效率相对较高,而慢生树种则相对较低。 展开更多
关键词 乡土树种 阔叶树种 营养元素分配 营养元素储量
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Resilience and response:Unveiling the impacts of extreme droughts on forests through integrated dendrochronological and remote sensing analyses 被引量:1
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作者 Han Shi Xi Peng +6 位作者 Yong-Jiao Zhou Ai-Ying Wang Xue-Kai Sun Na Li Quan-Sheng Bao Gude Buri Guang-You Hao 《Forest Ecosystems》 SCIE CSCD 2024年第4期491-501,共11页
Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate change.However,considerable uncertainty remains regarding the patte... Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate change.However,considerable uncertainty remains regarding the patterns in species-specific responses to extreme droughts.Here,we conducted a study integrating dendrochronology and remote sensing methods to investigate the mosaic-distributed maple-oak(native)natural forests and poplar plantations(introduced)in the Horqin Sandy Land,Northeast China.We assessed the impacts of extreme droughts on tree performances by measuring interannual variations in radial growth and vegetation index.The results showed that precipitation and self-calibrated palmer drought severity index(scPDSI)are the major factors influencing tree-ring width index(RWI)and normalized difference vegetation index(NDVI).The severe droughts between 2000 and 2004 resulted in reduced RWI in the three studied tree species as well as led to NDVI reductions in both the maple-oak natural forests and the poplar plantations.The RWI reached the nadir during the2000-2004 severe droughts and remained at low levels two years after the severe drought,creating a legacy effect.In contrast to the lack of significant correlation between RWI and scPDSI,NDVI exhibited a significant positive correlation with scPDSI indicating the greater sensitivity of canopy performance to droughts than radial growth.Furthermore,interspecific differences in RWI and NDVI responses were observed,with the fast-growing poplar species experiencing a more significant RWI decrease and more negative NDVI anomaly during severe droughts than native species,highlighting the species-specific trade-offs between drought resilience and growth rate.This study emphasizes the importance of combining tree-level radial growth with landscape-scale canopy remote sensing to understand forest resilience and response.Our study improves our understanding of forest responses to extreme drought and highlights species differences in climate responses,offering crucial insights for optimizing species selection in sustainable afforestation and forest management in water-limited regions under the influence of climate change. 展开更多
关键词 Introduced tree species native tree species NDVI Severe drought tree-ring width
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南亚热带乡土树种与桉树人工林土壤真菌群落多样性和功能类群的比较
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作者 席守鸿 明安刚 +2 位作者 谭玲 何江 覃林 《广西植物》 CAS CSCD 北大核心 2024年第7期1232-1244,共13页
营造乡土树种人工林和桉树人工林是我国南亚热带森林经营的常见模式。为探究土壤真菌群落多样性及功能对乡土树种和桉树人工林的响应特征与机制,该研究以南亚热带4个乡土树种人工林[马尾松(Pinus massoniana)、火力楠(Michelia macclur... 营造乡土树种人工林和桉树人工林是我国南亚热带森林经营的常见模式。为探究土壤真菌群落多样性及功能对乡土树种和桉树人工林的响应特征与机制,该研究以南亚热带4个乡土树种人工林[马尾松(Pinus massoniana)、火力楠(Michelia macclurei)、米老排(Mytilaria laosensis)、红锥(Castanopsis hystrix)]和外来树种尾巨桉(Eucalyptus urophylla×E.grandis)人工林为对象,基于各林分土壤(0~20 cm)真菌18S rRNA高通量测序数据,利用FUNGuild数据库,比较分析乡土树种与尾巨桉人工林土壤真菌群落多样性和功能类群的差异特性及影响的主导土壤环境因子。结果表明:(1)5个研究林分的土壤真菌优势门均为子囊菌门和担子菌门,但不同乡土树种林分与尾巨桉林的土壤真菌优势目存在差异。(2)尾巨桉林土壤真菌群落α多样性高于乡土树种人工林,其群落组成结构也与乡土树种人工林存在显著差异(P<0.05)。(3)4个乡土树种人工林土壤的腐生营养型的相对丰度高于尾巨桉林,并且火力楠林和米老排林土壤丛枝菌根真菌的相对丰度明显高于尾巨桉林,尾巨桉林土壤共生营养型以及外生菌根真菌和木材腐生菌的相对丰度明显高于乡土树种人工林。(4)pH是导致尾巨桉林与乡土树种人工林土壤真菌群落多样性和功能类群差异的主要土壤环境因子。综上认为,在南亚热带地区将尾巨桉林改建成火力楠林或米老排林可提高土壤养分水平,提升土壤生态功能。 展开更多
关键词 土壤真菌群落 Illumina MiSeq高通量测序 FUNGuild数据库 乡土树种人工林 桉树人工林
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乡土树种抗旱造林技术及可推广的树种 被引量:2
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作者 周玉峰 《林业科技情报》 2024年第3期112-114,共3页
通过对当前造林地的详细考察和研究,针对恶劣状况与持续干旱气候条件,指出了实施乡土树种抗旱造林技术必要性,并结合风沙源治理工程造林的实践,详细介绍了乡土树种抗旱造林技术及值得推广的乡土树种。
关键词 乡土树种 造林技术 推广树种
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基于乡土树种利用的龙丽温高速公路生态廊道改造 被引量:1
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作者 潘建林 毛朝明 丁敏 《绿色科技》 2024年第11期54-59,95,共7页
为提升高速公路生态廊道森林景观效果,建立了美丽生态廊道森林群落评价指标,调查了龙丽温高速公路廊道植被状况后发现,多年的人工经营改变了森林原有的自然植被特征,各种纯林脆弱与不稳定的缺陷,给森林可持续经营带来风险。根据森林演... 为提升高速公路生态廊道森林景观效果,建立了美丽生态廊道森林群落评价指标,调查了龙丽温高速公路廊道植被状况后发现,多年的人工经营改变了森林原有的自然植被特征,各种纯林脆弱与不稳定的缺陷,给森林可持续经营带来风险。根据森林演替规律,提出充分利用乡土树种,对不同群落使用间伐改造、补植、定向抚育等措施,增加森林群落内具有明显层次、叶色、花色和果色的乡土阔叶树种品种和数量;对容易发生森林火灾区域,种植耐火阔叶树种;清除外来有害生物、保护生物多样性的建设目标。通过改造,构造不同的景观斑块,形成具有空间和时间变化的异质景观,各种景观彼此镶嵌,季相变化明显,形成丰富多彩、美学价值高、生态功能强的美丽生态廊道景观。 展开更多
关键词 乡土树种 生态廊道 森林健康 森林景观 植物群落 生态美学 森林演替
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针阔凋落叶混合分解过程中可溶性有机碳释放的动态特征
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作者 李勋 张艳 +2 位作者 宋思梦 周扬 张健 《广西植物》 CAS CSCD 北大核心 2024年第7期1205-1217,共13页
为了调整低效马尾松(Pinus massoniana,P)人工纯林的林分结构,探明其与乡土阔叶树种凋落叶混合分解过程中的可溶性有机碳(DOC)释放规律,该研究以马尾松、香樟(Cinnamomum camphora,C)和香椿(Toona sinensis,T)的凋落叶为研究对象,将其... 为了调整低效马尾松(Pinus massoniana,P)人工纯林的林分结构,探明其与乡土阔叶树种凋落叶混合分解过程中的可溶性有机碳(DOC)释放规律,该研究以马尾松、香樟(Cinnamomum camphora,C)和香椿(Toona sinensis,T)的凋落叶为研究对象,将其按照不同树种和质量比例组合为15个处理(3个单一树种处理+12个混合处理)后进行野外凋落叶分解实验,并探讨DOC释放最佳的凋落叶树种组合以及混合比例。结果表明:(1)马尾松和大部分混合处理凋落叶(除了PT64)在分解初期(0~6个月)的DOC含量均显著升高,出现富集现象,之后随着分解时间的延长而降低,在分解中后期(12~18个月)或分解末期(18~24个月)再次出现小幅度的碳富集现象。阔叶所占比例越高,其后期DOC含量越低。(2)分解前期(0~6个月)凋落叶DOC释放的拮抗效应较强(58.33%),仅有8.33%(1/12)的混合处理表现出协同效应。之后(6~18个月)其协同效应逐渐增强(91.67%),分解末期(18~24个月)凋落叶的协同效应有所减弱(66.67%)。在所有混合处理中,PT64在整个分解期间均出现协同效应,其次为PT73、PCT622和PCT613在大部分分解时期(3/4)出现协同效应。(3)偏最小二乘法(PLS)回归分析表明,凋落叶初始质量因子中N含量、P含量、木质素含量、缩合单宁含量、C/N、C/P、木质素/N以及木质素/P是影响该研究区域中凋落物DOC释放的重要因素。总体而言,马尾松与阔叶凋落叶混合后的DOC释放受到树种、混合比例及分解时间的共同影响。相对于其他混合处理,阔叶占比大于等于30.00%且含有香椿(T)的凋落叶混合处理(PT64、PT73、PCT622和PCT613)更能促进DOC的释放。 展开更多
关键词 马尾松 乡土阔叶树种 混合凋落叶 可溶性有机碳 协同效应 拮抗效应
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城市建设中节约型园林植物群落存在问题和建议
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作者 周生龙 《工程建设与设计》 2024年第3期112-114,共3页
在杭州选取城市中心区域较为典型的具有节约型园林特征的8个公园,对其植物群落开展调查发现,多数公园森林覆盖率超过了50%,乔木树种的覆盖率占比依旧不高,不透水面积占比同样差异巨大;不同公园之间乔木树种覆盖率、草坪覆盖率差异巨大,... 在杭州选取城市中心区域较为典型的具有节约型园林特征的8个公园,对其植物群落开展调查发现,多数公园森林覆盖率超过了50%,乔木树种的覆盖率占比依旧不高,不透水面积占比同样差异巨大;不同公园之间乔木树种覆盖率、草坪覆盖率差异巨大,乔木树种、植物种类差异不同,乡土树种数量尚可;植物群落树种的丰富度差异并不明显。对于这些现状和问题,提出了提升园林景观的绿量、提高植物群落的丰富度、增加园林群落的郁闭度、增加抗旱树种的引入、提高立体绿化的比例、提高乡土植物的比例等建议。 展开更多
关键词 节约型园林 植物群落 乡土树种
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乡土树种在中原地区城市园林绿化中的应用
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作者 刘晓杰 《园艺与种苗》 CAS 2024年第4期50-52,共3页
我国中原地区夏季高温湿热,冬季寒冷干燥,这种气候环境对园林绿化中树种的适应能力要求较强,在选择园林绿化乡土树种配置时,既要确保其适合中原地区的自然环境,又要兼顾其品种的多样化与和谐性。该文通过对乡土树种在中原地区园林绿化... 我国中原地区夏季高温湿热,冬季寒冷干燥,这种气候环境对园林绿化中树种的适应能力要求较强,在选择园林绿化乡土树种配置时,既要确保其适合中原地区的自然环境,又要兼顾其品种的多样化与和谐性。该文通过对乡土树种在中原地区园林绿化应用中的重要作用进行分析研究,旨在为美丽、和谐城市建设提供参考。 展开更多
关键词 乡土树种 园林绿化 中原地区 最佳选择
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Application of Native Tree Species to Urban Forest 被引量:1
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作者 ZHOUZaohong GUOMeifeng WUGuoxun 《Chinese Forestry Science and Technology》 2004年第3期70-74,共5页
Native trees play important roles in urban forestry, such as a deep cultural background, a strong ecological adaptability, a high performance-cost ratio and a convenient management. But now there are some difficulties... Native trees play important roles in urban forestry, such as a deep cultural background, a strong ecological adaptability, a high performance-cost ratio and a convenient management. But now there are some difficulties in native trees’ utilization and popularization dueto few study on landscape plant. In order to seek an abnormal and artificial landscaping and to produce an effective resultas soon as possible, native and foreign plants can be properly used as an available resource by improving their technological level and emphasizing natural balance. Then Chinese classic culture and green economics can be combined with beautiful forestry by implementing urban sustainable development. 展开更多
关键词 native tree urban forestry CULTURE ECONOMICS China
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广州市从化区乡土树种资源及应用
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作者 詹子权 吴焕忠 林真光 《中南林业调查规划》 2024年第4期7-11,共5页
通过查阅历史资料、实地调查并走访当地群众,对广州市从化区的乡土树种资源及其利用现状进行调查,结果表明:从化区有乡土树种83科208属469种(含裸子植物6科9属14种,被子植物77科199属455种),其中乔木类乡土树种74科166属363种,灌木类乡... 通过查阅历史资料、实地调查并走访当地群众,对广州市从化区的乡土树种资源及其利用现状进行调查,结果表明:从化区有乡土树种83科208属469种(含裸子植物6科9属14种,被子植物77科199属455种),其中乔木类乡土树种74科166属363种,灌木类乡土树种38科63属106种;从化区的乡土树种中,有国家二级重点保护野生植物18种,隶属11科13属;从化区用于城区和四旁绿化的主要常见树种共有48科113属156种,其中乡土树种39科64属88种,占总种数的56.41%;外来树种25科55属68种,占总种数的43.59%。根据调查结果,对从化区当前乡土树种的绿化应用现状进行分析,并提出应用建议。 展开更多
关键词 乡土树种 资源 利用 从化区
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