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森林衰退病研究现状及展望 总被引:8,自引:2,他引:8
文章对我国森衰退病的研究现状和发展概况进行了综述,并介绍了国外有关臭氧、酸沉降及森林衰退病与立地相关性等研究的重要进展。对于Manion的森林衰退病概念中的若干问题如非生物和生物因素的顺序、衰退病最终结果是导致树木死亡、森林衰退病的起因等进行了讨论。最后对我国森林衰退病研究提出了几点建议。 相似文献
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本文就“森林衰退病”(Forest decline)理论的概念、意义,森林衰退病病原,“衰退病”(Decline,Dicline disease)模式,以及诱发因素(Predisposing factors)、激化因素(Inciting factors)和促进因素(Contributing factors)之间的相互关系作了综述介绍,并看重强调了运用这一新的植物病理学理论,认识和指导我国林业及热作生产的重要现实意义。 相似文献
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国外森林衰退病病原的若干概念 总被引:3,自引:0,他引:3
森林衰退病发生的原因,国外的学者对此有不同的见解,其致病因素也由单一因素发展到多种因素,因而在衰退病病原方面提出了若干的概念。该文就目前病原的几种概念进行简要叙述。 相似文献
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新疆阿尔泰山两河源自然保护区森林的衰退,人为干扰是原因之一,但有些树种出现顶梢枯死、大片树木死亡等体现森林衰退的现象。本文通过对森林衰退原因的分析,为今后森林衰退研究提供方法。近年来,森林衰退现象在全球日益普遍,尤其是北 相似文献
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扼要评述了国内外对橡胶树死皮病病因的研究;在前人研究和对云南橡胶树死皮病发生发展大量田间资料研究的基础上,结合作物栽培学、营养学和森林衰退病的基本理论,提出橡胶树死皮病是橡胶树群体在一定的割胶生产条件下营养失衡,导致整株或局部树皮组织衰退,局部或全部失去排胶功能的一种生理病害,而过度排胶,养分不能适时足量供给,是死皮病不同程度发生、发展的主要病因。 相似文献
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景观病理学:森林保护学领域的新视角 总被引:5,自引:0,他引:5
景观病理学是以植物病理学和森林病理学理论为基础,结合景观生态学的空间和时间分析原理和方法而形成的新的交叉学科。景观病理学能够帮助明辨立地因素、植被空间格局的变化对树木感病性和病害流行方式的影响;并且有助于明确气候变化可能导致的病原快速进化和变异、树木对这种变化的滞后效应。同时,景观病理学的研究有助于预测病原的扩散速率及其对空间格局的影响,有助于规划土地持续利用方式、制定森林病虫害可持续治理的决策。本文诠释景观病理学的概念和研究方法;对景观病理学研究所取得的最新研究进展进行评述,并提出景观病理学急需解决的几个问题。 相似文献
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Ross Meentemeyer David Rizzo Walter Mark Elizabeth Lotz 《Forest Ecology and Management》2004,200(1-3):195-214
Sudden oak death, caused by the recently described pathogen Phytophthora ramorum, is an emerging forest disease that has reached epidemic levels in coastal forests of central California. We present a rule-based model of P. ramorum establishment and spread risk in California plant communities. The model, which is being used as a management tool to target threatened forests for early-detection monitoring and protection, incorporates the effects of spatial and temporal variability of multiple variables on pathogen persistence. Model predictions are based on current knowledge of host susceptibility, pathogen reproduction, and pathogen transmission with particular regard to host species distribution and climate suitability. Maps of host species distributions and monthly weather conditions were spatially analyzed in a GIS and parameterized to encode the magnitude and direction of each variable's effect on disease establishment and spread. Spread risk predictions were computed for each month of the pathogen's general reproductive season and averaged to generate a cumulative risk map (Fig. 6a and b). The model identifies an alarming number of uninfected forest ecosystems in California at considerable risk of infection by Phytophthora ramorum. This includes, in particular, a broad band of high risk north of Sonoma County to the Oregon border, a narrow band of high risk south of central Monterey County south to central San Luis Obispo County, and scattered areas of moderate and high risk in the Sierra Nevada foothills in Butte and Yuba counties. Model performance was evaluated by comparing spread risk predictions to field observations of disease presence and absence. Model predictions of spread risk were consistent with disease severity observed in the field, with modeled risk significantly higher at currently infested locations than at uninfested locations (P < 0.01, n = 323). Based on what is known about the ecology and epidemiology of sudden oak death, this model provides a simple and effective management tool for identifying emergent infections before they become established. 相似文献
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森林病理学是一门应用植物病理学的基本概念、原理和方法,研究森林植物病害的发生机制与防控技术的自然科学。作为一门独立的学科始建于19世纪80年代前后,随后的100多年来,森林病理学已形成完整的学科体系。受当代生命学科整体飞速发展的推动和人类社会全球一体化战略背景的影响,当代森林病理学被赋予更丰富的内涵。森林病理学的研究目标兼顾国家经济利益和国家生态安全,具体研究对象包括寡元单纯系统、多元单纯系统和多元复杂系统,研究尺度跨越基因、细胞、组织、个体、种群、群落、生态系统到景观的各个尺度并展开在气候变化背景下的全球一体化研究,研究方法则更加侧重多学科的交叉技术体系,防控策略也不断呈现出新的主题和与自然的和谐统一。概括森林病理学经过100多年来的发展,在当今世界各国的研究现状和特征,为促进森林病理学与生命科学领域其他学科更加紧密地结合,推动森林病理学的发展提供借鉴。 相似文献
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Localized within‐ and between‐tree variation in nematode distribution during latent state of pine wilt disease makes the disease status cryptic 下载免费PDF全文
The pinewood nematode (PWN), Bursaphelenchus xylophilus, is the causal agent of pine wilt disease, an epidemic disease that has severely damaged pine forests in East Asia. The disease has spread to northern areas in Asia and parts of Europe. To prevent disease spread as the forefront of damage prevention, a better understanding of infection status is highly important. Not all infected trees show disease symptoms, and such asymptomatic PWN‐carrying trees are likely to be overlooked and can become a pathogen reservoir. To elucidate PWN infection status in asymptomatic trees, we performed PWN inspection of branches and trunks in 21 test trees in two different conditions: trees that had experienced PWN inoculation and those with suspected PWN infection that had experienced transient foliage discoloration. We detected PWNs in eight test trees (38%) and in 13 (1.5%) of a total of 843 samples. The difference in these percentages suggests that nematode inhabitation was highly localized within the trees, possibly owing to the restricted migration of PWNs. Our data demonstrated that trees that were once weakened but recovered their vigour can persist, as the asymptomatic carriers, in the forest. The implications for disease control are also discussed. 相似文献
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Harvest index is defined and its relationship with primary production, biomass partitioning and yield components in forest trees examined. As stand density has been found to have a major effect on harvest index, it is concluded that further development of the harvest index concept in forest trees will need to take account of density-yield relationships. 相似文献
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在对林间白僵菌宿存场所、松毛虫种群密度和针叶含水量等进行野外调查和室内测定的基础上,用逐步回归分析方法,建立了空间状态马尾松毛虫白僵病流行的主因素相关模型,并应用模糊聚类方法,对白僵病的流行程度进行了划分.揭示了白僵病在林间流行所必备的奇主、病原和环境间的相互作用关系.为马尾松毛虫白僵病流行的预测提供了理论依据. 相似文献
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Forest cover change is one of the defining contemporary environmental changes that validate the proposition of the Anthropocene narrative. Forest transition is a well-recognized global phenomenon, which has been studied and explained in well elaborated forest transition theory. Forest transition has been observed in over 30 countries, and it has been a trend in multiple countries in Asia. Forest transition is most relevant for the Anthropocene narrative, as it suggests that forest cover decline may eventually be followed by a forest cover increase at the global scale. The paper reviews evidence of forest transition in eight Asian countries and juxtaposes this with global forest cover trends. In Asia countries like China, India, Japan, Philippines, South Korea, and Japan and Vietnam are among the countries that have experienced an increase in the area under some kind of tree cover. Complex interplays of forest cover, population growth, economic development, demand for forest goods and services and governance effectiveness are the driving forces of forest transition. While it is not possible to extrapolate Asia's forest transition to the global scale, the Asian experience makes it possible to make statements on possible global forest cover scenarios. Ultimately, forest transition theory in general, and the experience of forest transition in Asia also support the concept and related narrative of the Anthropocene. 相似文献
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世界森林经营思想的演变及其对我们的启示 总被引:9,自引:0,他引:9
本文回顾了世界森林经营思想和实践的演变过程,对“森林的永续经营”和“森林的可持续经营”概念进行了诠释,同时指出“森林的可持续经营”概念目前已为世界上众多政治家和林业工作者所接受,从而成为当今世界森林经营的主体思想。作者还根据近年来国际森林问题的发展动态,就我国的林业发展提出了几点思考。作者认为,保持森林的环境保护与生产作用的平衡是至关重要的,在重视生态保护的同时,切莫忽略了森林的传统功能——生产。 相似文献