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草食作用对泰来草地上地下资源分配的影响
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作者 贾碧莹 刘思雨 +1 位作者 赵杨赫 毛伟 《热带生物学报》 2023年第6期593-601,共9页
为了研究海草床生态系统内中小型草食动物对泰来草地上地下资源分配的影响,以海南优势海草泰来草(Thalassia hemprichii)为研究对象,通过原位搭建隔离笼与放置化学驱逐剂(西维因)模拟排除不同消费者对海草的取食作用。结果表明:泰来草... 为了研究海草床生态系统内中小型草食动物对泰来草地上地下资源分配的影响,以海南优势海草泰来草(Thalassia hemprichii)为研究对象,通过原位搭建隔离笼与放置化学驱逐剂(西维因)模拟排除不同消费者对海草的取食作用。结果表明:泰来草的根冠比随时间表现出升高的趋势,不同处理之间的根冠比差异不显著。消费者的采食会降低泰来草的生物量;排除两类消费者处理(MF)的泰来草地上生物量高于不排除消费者的空白对照处理(CK);草食作用会增加泰来草地上部分的有机碳和全氮含量的分配比以维持其正常生长,但对全磷含量的影响未达到显著水平。总体而言,草食作用增加了泰来草根冠比,调控了地上地下部分的生物量、有机碳、全氮、全磷的分配,用于提高对资源的吸收和同化速率,躲避消费者的采食,维持种群延续。 展开更多
关键词 草食作用 泰来草 功能性状 根冠比
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植物防卫的碳-养分平衡假说 被引量:4
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作者 邓斌 曾德慧 《生态学杂志》 CAS CSCD 北大核心 2006年第4期449-455,共7页
碳-养分平衡假说(carbon-nutrient balance hypothesis,CNBH)认为,植物组织中次生代谢物浓度受环境碳-资源有效性控制;植物体内次生代谢物按照化学计量的要求进行分配;资源分配给防卫物的必要条件是资源供应量满足植物生长需求后仍过剩... 碳-养分平衡假说(carbon-nutrient balance hypothesis,CNBH)认为,植物组织中次生代谢物浓度受环境碳-资源有效性控制;植物体内次生代谢物按照化学计量的要求进行分配;资源分配给防卫物的必要条件是资源供应量满足植物生长需求后仍过剩。CNBH自提出以来,其适用范围不断受到限制,解释与预测研究结果的能力逐渐显现不足。期间,对CNBH进行过优化和修改,设置了多种限制条件,以期能使CNBH得到补救,继续成为指导植物-草食动物间相互作用和植物体内资源分配的相关理论。然而,随着研究的逐渐深入,CNBH被证实缺乏逻辑性和内在一致性;CNBH不能满足假说本身的发展要求,缺乏明确可行的量化指标体系,也没有明确地标识出理论预测范围与可测试范围之间的界限。研究表明,CNBH的基本假设本身是错误的;随着人们对植物-草食动物间相互作用的认知能力加强,更深刻地认识到资源在植物体内的分配模式,意识到CNBH假说的严重缺陷。在现有的植物防卫理论中,生长-分化平衡假说(growth-differentiation balance hypothesis)较为成熟,不但具有CNBH的优点,而且更具有植物生理学和进化基础,可以成为CNBH的替代假说。 展开更多
关键词 碳-养分平衡假说 生长-分化平衡假说 植物-草食动物间相互作用 资源有效性 次生代谢物 植物防卫
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Geographical distribution of red and green Noctiluca scintillans 被引量:13
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作者 P. J. HARRISON K. FURUYA +8 位作者 P. M. GLIBERT J. Xu H. B. LIU K. YIN J. H. W. LEE D. M. ANDERSON R. GOWEN A. R. AL-AZRI A. Y. T. HO 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第4期807-831,共25页
The dinoflagellate Noctiluca scintillans is one of the most important and abundant red tide organisms and it is distributed world-wide. It occurs in two forms. Red Noctiluca is heterotrophic and fills the role of one ... The dinoflagellate Noctiluca scintillans is one of the most important and abundant red tide organisms and it is distributed world-wide. It occurs in two forms. Red Noctiluca is heterotrophic and fills the role of one of the microzooplankton grazers in the foodweb. In contrast, green Noctiluca contains a photosynthetic symbiont Pedinomonas noctilucae (a prasinophyte), but it also feeds on other plankton when the food supply is abundant. In this review, we document the global distribution of these two forms and include the first maps of their global distribution. Red Noctiluca occurs widely in the temperate to sub-tropical coastal regions of the world. It occurs over a wide temperature range of about 10℃ to 25℃ and at higher salinities (generally not in estuaries). It is particularly abundant in high productivity areas such as upwelling or eutrophic areas where diatoms dominate since they are its preferred food source. Green Noctiluca is much more restricted to a temperature range of 25℃-30℃ and mainly occurs in tropical waters of Southeast Asia, Bay of Bengal (east coast of India), in the eastern, western and northern Arabian Sea, the Red Sea, and recently it has become very abundant in the Gulf of Oman. Red and green Noctiluca do overlap in their distribution in the eastern, northern and western Arabian Sea with a seasonal shift from green Noctiluca in the cooler winter convective mixing, higher productivity season, to red Noctiluca in the more oligotrophic warmer summer season. 展开更多
关键词 Noctiluca global distribution distribution map green Noctiluca DINOFLAGELLATE
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Process development for producing a food-grade glucose solution from rice straws
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作者 Chih-Heng Wang Wen-Hua Chen +3 位作者 Hwai-Shen Liu Jinn-Tsyy Lai Cheng-Che Hsu Ben-Zu Wan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第2期386-392,共7页
In this paper, processes for producing a food-grade glucose solution through enzymatic hydrolysis of celluloserich solids obtained from rice straws are presented. The rice straws were pretreated by acid-catalyzed stea... In this paper, processes for producing a food-grade glucose solution through enzymatic hydrolysis of celluloserich solids obtained from rice straws are presented. The rice straws were pretreated by acid-catalyzed steam explosion, and the reaction efficiency, toxicity control, and process economic feasibility were studied. Mass transfer resistance to the hydrolysis reaction was reduced by grinding with glass beads. A higher glucose concentration could be obtained by feeding more cellulose in the hydrolysis reaction; however, this also resulted in the production of undesired byproducts. Thus, a soaking process for the cellulose solids in water was developed to effectively reduce the generation of byproducts in the hydrolysis reaction. The resulting food-grade glucose solution can provide 414 kilocalories per liter, and could be used during a food-shortage crisis in the future.The current production cost is estimated to be 0.82 USD·L^(-1). 展开更多
关键词 Cellulose Enzymatic hydrolysis Food-grade glucose solution Rice straw Biochemical engineering
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海草生态系统与濒危海洋哺乳动物儒艮的相互关系 被引量:2
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作者 邱广龙 周浩郎 +1 位作者 覃秋荣 范航清 《海洋环境科学》 CAS CSCD 北大核心 2013年第6期970-974,共5页
回顾了濒危动物儒艮(Dugong dugon)与其取食地海草生态系统的相互关系。在海草资源丰富的情况下,儒艮一般只主动进食海草,但对不同种类的海草也有不同偏好。尽管儒艮至少取食12种海草,但二药藻(Halodule uninervis)和喜盐草(Halophila o... 回顾了濒危动物儒艮(Dugong dugon)与其取食地海草生态系统的相互关系。在海草资源丰富的情况下,儒艮一般只主动进食海草,但对不同种类的海草也有不同偏好。尽管儒艮至少取食12种海草,但二药藻(Halodule uninervis)和喜盐草(Halophila ovalis)是儒艮最主要的食物来源。一旦海草床衰退,将对儒艮的生活史、繁殖生物学甚至能否存活产生重要影响。儒艮的取食加剧了海草床的空间异质化,改变了海草植物的形态、有性繁殖以及营养组成结构,改变了海草群落的种类组成以及演替序列,降低了海草床内底栖动物群落的生物多样性与密度,提高了海草床水体环境中的悬浮物含量。儒艮与海草床是一个相互影响的整体,应采用基于生态系统的观点、海岸带综合管理和跨边界管理的方法来进行保护和管理。 展开更多
关键词 动物一植物相互关系 草食作用 二药藻 喜盐藻 儒艮 海草床
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Evolution of herbs: key to the conundrum might be tolerance not avoidance
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作者 Adam Klimes Martin Weiser +1 位作者 Tomás Koubek Tomás Herben 《Journal of Plant Ecology》 SCIE CSCD 2021年第5期911-919,共9页
Aims Woody plants represent the ancestral growth form in angiosperms with herbs evolving repeatedly from them.While there are a number of hypotheses about drivers of the evolution of the herbaceous habit,the ability t... Aims Woody plants represent the ancestral growth form in angiosperms with herbs evolving repeatedly from them.While there are a number of hypotheses about drivers of the evolution of the herbaceous habit,the ability to avoid frost damage in winter by discarding their aboveground biomass has often been invoked as the main force in their evolution.We propose instead that any unpredictable disturbance might have been much more important than the seasonal frost,as herbs easily survive repeated disturbance.Methods We tested this hypothesis by comparing herbs and woody plants in their ability to deal with three types of simulated disturbances,more predictable winter freezing,less predictable spring freezing and herbivory.Comparison was made in an experimental common garden setup with 20 species differing in woodiness.We evaluated the effects of these disturbances on mortality and regrowth of plants.Important Findings Herbs did not have an advantage over woody plants in survival when exposed to winter freezing.In less predictable conditions of spring freezing herbs survived the treatment better than woody plants and this advantage was even larger in case of the simulated herbivory treatment.The advantage of herbs over woody plants in less predictable conditions suggests that herbaceous growth form might be an adaptation to unpredictable disturbance,which herbs are able to tolerate thanks to their ability to survive loss of aboveground biomass.Consequently,factors such as mammal herbivory or fire might have been the most likely factors in the transition from woody species to herbs. 展开更多
关键词 common garden experiment HERBIVORY PREDICTABILITY spring freezing winter freezing
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Co-existence thresholds in the dynamics of the plant-herbivore interaction with Allee effect and harvest
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作者 Manalebish Debalike Asfaw Semu Mitiku Kassa Edward M. Lungu2 《International Journal of Biomathematics》 SCIE 2018年第4期229-255,共27页
In the interaction between plants and herbivores that live in the same ecosystem, understanding the conditions in which co-existence equilibrium occurs answers a major question in Ecology. In this interaction, plants ... In the interaction between plants and herbivores that live in the same ecosystem, understanding the conditions in which co-existence equilibrium occurs answers a major question in Ecology. In this interaction, plants serve as food for herbivores on the food chain. Then the livelihood of herbivores highly depends on the availability of food, in this case the availability of plants. Moreover, the abundance of the plant density alone does not guarantee the non-extinction of the herbivore population as they are assumed to reproduce sexually. With this motivation, in this paper a predator-prey mathematical model is reformulated such that the death rate of the herbivore population is dependent on the plant density and their emergence is also governed by the Allee effect. Using the mathematical theory of dynamical system, threshold conditions are obtained for the non-extinction of the herbivore population and a trapping region is obtained to ensure co-existence of the population. Moreover, it has been shown that the dynamics of the population is significantly sensitive to the feeding rate and the harvest rate of the herbivore population. 展开更多
关键词 PREDATOR-PREY Allee effect HARVEST equilibrium points THRESHOLD sensitivityanalysis.
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