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1.
我国著名生态学家、中国工程院院士李文华先生组织国内在生态学及相关领域卓有成就的近二十位院士和近百位生态学一线领军人物,率领400余位作者历时两年时间共同撰写了《当代中国生态学研究》。《中国当代生态学研究》全书包括生物多样性保育、生态系统管理、生态系统恢复、全球变化生态学以及可持续发展生态学5卷。1.生物多样性保育卷,内容涵盖了生物多样性的调查与保护、评估与监测的研究及进展,以及生物多样性可持续利用的技术和物种/群落管理的案例研究,涉及海洋、农业、动物、植物、鸟类、鱼类、药物、微生物和菌物等多个门类。  相似文献   

2.
森林植被恢复重建的理论基础   总被引:21,自引:2,他引:19  
作者认为 :恢复生态学是研究如何修复由于人类活动引起的原生生态系统生物多样性和动态损害的一门学科 ,它是森林植被恢复重建的重要理论基础 .就森林植被而言 ,它主要研究退化森林生态系统的成因、特征、恢复可行性评价、恢复技术、恢复生态系统的生态学过程、恢复过程中的生物安全以及恢复理论 .其具体理论包括 :植被的发生与气候及气候的变迁耦合或生物的发生与环境耦合理论、植物多样性是生态系统稳定性的基础理论、生态演替理论和作为系统的生态系统的结构和功能相适应理论等 .从国内大量的生态恢复重建实践来看 ,森林植被的恢复重建研究需要解决以下一些问题 :注重探讨森林植被退化的进化与历史决定因素、注意研究恢复森林生态系统在恢复中的生态学过程、重视森林植被恢复重建中的生物安全问题以及大尺度的森林植被恢复重建问题  相似文献   

3.
采用田间调查、室内鉴定及生态学分析方法研究了有机稻田和常规稻田浮游动物的组成、丰富度及多样性。结果在有机稻田检测到溞属(Daphnia)、裸腹溞属(Moina)、剑水蚤属(Cyclops)和小剑水蚤属(Microcyclops)浮游动物,而在常规稻田仅检测到3属浮游动物;浮游动物的丰度与多样性指数均表现为有机稻田>田头水沟>常规稻田。表明有机栽培可显著增加稻田生态系统浮游动物的多样性。  相似文献   

4.
生态系统呼吸是草地生态系统碳交换过程的主要环节,也是草地生态系统中有机碳以CO2形式排放到大气中的主要途径。本文通过分析和总结已有研究的相关成果,探讨了国内外生态系统呼吸的不同测定方法以及影响草地生态系统呼吸的主要因素,揭示了现有研究中普遍存在的单一化研究方法以及单因素试验研究手段对生态系统呼吸研究结果产生不确定性。为准确估算生态系统呼吸值,建议以多因素交互试验作为主要研究手段,并采取不同测定方法,长期开展野外观测研究。  相似文献   

5.
秸秆还田配施化肥对砂姜黑土固碳细菌的影响   总被引:1,自引:0,他引:1  
农田生态系统是陆地生态系统中最活跃且固碳潜力最大的碳库之一,其中,细菌在农田生态系统生物固碳过程中发挥着重要作用。采用PCR-克隆测序技术、末端限制性酶切长度多态性分析技术(T-RFLP)及荧光定量PCR技术研究了不施肥(CK),施氮磷钾肥(CK-F),单独秸秆还田(W-NF)和施氮磷钾加秸秆还田(W-F)4种施肥管理对砂姜黑土固碳细菌群落结构、多样性及丰度的影响。结果表明,秸秆还田土壤的固碳细菌主要包括Nitrosomonas,Mesorhizobium和Bradyrhizobium等。在CK和W-NF处理中,土壤固碳细菌以严格自养菌为主,优势种群为亚硝化单胞菌属(Nitrosomonas),相对丰度分别为73.2%和72.4%。在CK-F和W-F处理中,土壤固碳细菌中严格自养菌相对丰度减小,而兼性自养菌相对丰度大幅增加。其中,CK-F的优势种群为亚硝化单胞菌属(Nitrosomonas)和中慢生根瘤菌属(Mesorhizobium),相对丰度分别为33.3%和17.6%。W-F的优势种群为亚硝化单胞菌属(Nitrosomonas)和慢生根瘤菌属(Bradyrhizobium),相对丰度分别为26.4%和24.5%。施用化肥及秸秆还田均显著提高了土壤固碳细菌群落的多样性,其中化肥的影响大于秸秆还田。主成分结果显示施肥对土壤固碳细菌群落结构的影响大于秸秆还田。4个处理土壤固碳功能基因(cbb L)丰度为1.32×107~3.29×107拷贝·g-1(干土),施肥及秸秆还田均能显著提高土壤细菌cbb L基因丰度,其中秸秆还田配施化肥的cbb L基因丰度最大。上述结果表明了施肥及秸秆还田对土壤固碳细菌群落结构,多样性及数量均有显著的影响。  相似文献   

6.
退化生态系统生态恢复评价与生物多样性   总被引:7,自引:2,他引:5  
概述了退化生态系统恢复过程中生物多样性研究概况,退化生态系统生态恢复评价研究现状,以及指示生物在退化生态系统生态恢复评价中的应用.指出应加强对指示生物的生物学特点及生态学意义的研究,揭示其与植被恢复、土壤恢复乃至生态系统功能恢复之间的相关性,明确指示生物在生态恢复评价中.的指示意义.同时,通过考察植被结构、物种多样性及生态系统过程来评价生态恢复的方法值得学习和借鉴.  相似文献   

7.
固碳微生物分子生态学研究   总被引:17,自引:0,他引:17  
 减缓大气“温室效应”是目前最重要且亟待解决的环境问题之一。自养微生物具有极强的环境适应性和不容忽视的固碳潜力,研究微生物固定CO2的分子生态机理对于缓解全球气候变暖具有重要科学意义。目前发现的5条主要生物固碳途径中,卡尔文循环是自养生物固定CO2的主要途径,其中核酮糖-1,5-二磷酸羧化酶/加氧酶(RubisCO)是卡尔文循环中的关键酶,因此RubisCO及其编码基因被许多学者用于不同生态环境中固碳微生物群落结构和多样性的研究。以前的研究主要集中在水生生态系统,揭示了不同水生生态系统中固碳微生物的群落特点及其对不同生境的响应规律。近几年,随着陆地生态系统固碳微生物分子生态学研究的深入,国外学者发现土壤中存在大量的固碳自养微生物,它们在土壤中所起的具体作用和贡献有待进一步研究和验证。至今,国内针对土壤固碳微生物分子生态学的研究还未见报道。论文对固定CO2的微生物种类、固定机理以及近年来关于微生物固定CO2的分子生态学的研究进行了分析和总结,讨论了固碳微生物分子生态学研究存在的主要问题和今后的发展方向,旨在为中国固碳微生物分子生态学研究提供参考。  相似文献   

8.
通过调查同一个森林生态系统不同样地中多个树种根际范围内土壤可溶性有机碳和土壤有机碳的含量,分析和探讨影响森林生态系统土壤可溶性有机碳和土壤有机碳空间异质性的环境因素。本项目在云南哀牢山亚热带中山湿性常绿阔叶原生林生态系统中进行,选择3个山谷样地上游森林生态系统原生土区域中7个主要树种作为研究对象,调查0~10 cm表层土壤可溶性有机碳和土壤有机碳的含量。研究结果表明:硬壳柯、变色锥、木果柯、多花山矾和南洋木荷等5个乔木树种根际范围内土壤可溶性有机碳和土壤有机碳含量显著高于云南连蕊茶和云南越桔2个灌木树种根际范围内土壤可溶性有机碳和土壤有机碳含量;5个乔木树种中硬壳柯和南洋木荷2个树种根际范围内土壤可溶性有机碳和土壤有机碳含量明显大于另外3个乔木树种,说明不同树种对土壤可溶性有机碳和土壤有机碳的空间异质性有明显影响。7个不同树种根际范围内土壤可溶性有机碳含量、土壤有机碳含量和土壤可溶性有机碳含量占土壤有机碳含量的比例在老君山神山谷样地中达到最大值,在三棵树山谷样地中降低为最低值,说明不同山谷样地中的环境条件也可以显著影响土壤可溶性有机碳和有机碳含量及两者之间的比例。本项目研究结果充分证明森林生态系统土壤可溶性有机碳和土壤有机碳空间分布规律的复杂性和环境控制因子的多样性,可为全球各种类型森林生态系统土壤有机碳成分和碳贮量等方面的研究内容提供新的思路和方向。  相似文献   

9.
CENTURY模型在不同生态系统中的研究与应用   总被引:2,自引:0,他引:2  
《山西农业科学》2015,(11):1563-1566
对国际上通行的CENTURY模型在国内外草地、森林、农田3个不同生态系统中的研究与应用现状进行分析,为利用该模型开展不同生态系统的土壤有机碳变化研究提供依据。CENTURY模型最初被应用于模拟草地生态系统,主要用于模拟草地生态系统中的C,N,P,S等元素的长期演变过程,模拟效果比较好,后被国内外众多学者成功应用于不同地区的众多试验站点,模型中的大多数参数具有普适性,适用于不同生态区的草地生态系统,并获得了适应性验证;CENTURY模型升级改进后开始广泛应用于森林生态系统,模拟土壤与植被系统间C,N,P,S的长期动态,组成包括森林子系统、土壤有机质子模型和水分子模型,但该模型对模拟有枯枝落叶层的森林土壤有机碳的变化存在结构性问题;CENTURY模型是当前评价农田生态系统土壤有机碳演变最有效的工具之一,国内外学者已将其广泛应用于农田生态系统土壤有机碳变化研究中。通过对国际上通行的CENTURY模型在草地、森林、农田3个不同生态系统中的研究与应用进行总结,对CENTURY模型在应用中存在的问题进行分析,得出CENTURY模型有着广泛的应用前景。  相似文献   

10.
测定了4 个季节的大型垂直潜流人工湿地中基质有机碳含量,以研究植物组成与多样性,包括植物物 种多样性,功能群多样性与植物组成对有机碳季节动态的影响方差分析结果表明院在大型人工湿地中,春季,冬季 植物物种多样性对基质有机碳含量有显著正效应且植物组成四季都有极显著的影响,而功能群多样性四季中都没 有显著效应,因而,当衡量植物多样性对基质营养季节动态如有机碳”的影响时,一般是植物组成和物种多样性要 比功能群多样性更具有说服力,同时,基质有机碳含量在春季,冬季较高而在夏秋季较低,表明基质营养(如有机 碳)的季节动态变化趋势与植物的生长周期相一致,另外四季中基质有机碳含量与基质容重呈显著正相关,而在 2008 年10 月植物生物量与基质有机碳含量呈显著负相关。  相似文献   

11.
We demonstrated in laboratory experiments that temperature control of marine bacteria action on diatoms strongly influences the coupling of biogenic silica and organic carbon preservation. Low temperature intensified the selective regeneration of organic matter by marine bacteria as the silicon:carbon preservation ratio gradually increased from approximately 1 at 33 degrees C to approximately 6 at -1.8 degrees C. Temperature control of bacteria-mediated selective preservation of silicon versus carbon should help to interpret and model the variable coupling of silicon and carbon sinking fluxes and the spatial patterns of opal accumulation in oceanic systems with different temperature regimes.  相似文献   

12.
Viruses have been hypothesized to control blooms of Aureococcus anophagefferens gen. et sp. nov. (Chrysophyceae), a marine phytoplankton that since 1985 has caused devastating summer blooms called "brown tide." By means of ultrafiltration methods, viruses specific to this alga were isolated from both the Great South Bay and Peconic Bay systems of Long Island, New York, during the summer bloom period of 1992. Cell lysis of healthy algal cultures was demonstrated, as well as continuing reinfection with serial transfers of cultures. Electron microscope surveys yielded images of phage-like virus particles with tails that could attach to A. anophagefferens cells within minutes of exposure. The isolation and cultivation of this virus highlights the need for further study of viral infection of eukaryotic algae and the potential for a better understanding of algal bloom control by viral infection.  相似文献   

13.
Seven carbonaceous chondrites have been analyzed for soluble organic compounds, carbonate, and residual carbon. Carbon-13/carbon-12 isotopic mneasurements on these fractions gave the following values relative to a marine carbonate standard: carbonate, +40 to +70 per mil; residual carbon, -15 to -17 per mil; soluble organic material, -17 to -27 per mil, with one value of -5.5 per mil. These values are interpreted to indicate that carbonate, residual carbon, and part of the extractable organic material are endogenous to these meteorites.  相似文献   

14.
The chemoautotrophic fixation of carbon dioxide by bacteria is responsible for an appreciable component of the organic carbon in a sulfide-rich marine mud. A peak of carbon dioxide fixation (at 40 centimeters subbottom) coincides with peaks in the organic carbon content, the ratio of carbon to nitrogen, and bacterial cell counts. Stimulation of fixation by thiosulfate and inhibition by anaerobic conditions implicate the chemoautotrophic sulfur bacteria as primary producers in this environment.  相似文献   

15.
土壤有机碳库是陆地生态系统中最重要的碳库。土壤侵蚀是导致陆地碳库衰减的主要动力之一,也是陆地碳汇与海洋碳汇相互作用的重要过程。从不同角度阐述了物理和人为因素对侵蚀区域土壤有机碳迁移蓄积过程的影响,尤其关注了侵蚀过程碳的重新再分配,这一点是准确预测土壤有机碳循环对碳源/汇贡献及准确评估碳收支的关键。针对土壤有机碳循环的特点,提出亟待解决的问题。  相似文献   

16.
[目的]调查鸭病毒性肝炎的病原,并分析近年来该病不断发生和难以控制的原因。[方法]从山东临沂、潍坊、滨州等地区鸭场有鸭肝炎典型症状的雏鸭的肝、脾中分离病毒,通过鸡胚和鸭胚接种、RT-PCR检测、血清学试验、攻毒试验等研究其病原特性。[结果]分离到4株鸭病毒性肝炎病毒(DHV),第5代鸭胚分离毒的ELD50为103.41~105.20,与传统的Ⅰ型DHV的血清交叉保护率为20%~80%。分离株对4日龄雏鸭的致死率为50%~100%。攻毒后雏鸭均出现典型的鸭肝炎症状,24~48 h出现死亡高峰。[结论]DHV分离株的毒力存在地区差异。  相似文献   

17.
Degradation of marine organic carbon provides a major source of atmospheric carbon dioxide, whereas preservation in sediments results in accumulation of oxygen. These processes involve the slow decay of chemically recalcitrant compounds and physical protection. To assess the importance of physical protection, we constructed a reaction-diffusion model in which organic matter differs only in its accessibility to microbial degradation but not its intrinsic reactivity. The model predicts that organic matter decays logarithmically with time t and that decay rates decrease approximately as 0.2 x t(-1) until burial. Analyses of sediment-core data are consistent with these predictions.  相似文献   

18.
The study of viruses has traditionally focused on their roles as infectious agents and as tools for understanding cell biology. Viruses are now finding a new expanded role as nanoplatforms with applications in materials science and medicine. Viruses form highly symmetrical monodisperse architectures and are ideal templates for engineering multifunctionality, including multivalent display of surface ligands and encapsulation of inorganic and organic materials. These developments assure that viruses will find applications as versatile nanoscale materials.  相似文献   

19.
Developments in soil biology and in methods to characterize soil organic carbon can potentially deliver novel soil quality indicators that can help identify management practices able to sustain soil productivity and environmental resilience. This work aimed at synthesizing results regarding the suitability of a range of soil biological and biochemical properties as novel soil quality indicators for agricultural management. The soil properties, selected through a published literature review, comprised different labile organic carbon fractions [hydrophilic dissolved organic carbon, dissolved organic carbon, permanganate oxidizable carbon (POXC), hot water extractable carbon and particulate organic matter carbon], soil disease suppressiveness measured using a Pythium-Lepidium bioassay, nematode communities characterized by amplicon sequencing and qPCR, and microbial community level physiological profiling measured with MicroRespTM. Prior studies tested the sensitivity of each of the novel indicators to tillage and organic matter addition in ten European long-term field experiments (LTEs) and assessed their relationships with pre-existing soil quality indicators of soil functioning. Here, the results of these previous studies are brought together and interpreted relative to each other and to the broader body of literature on soil quality assessment. Reduced tillage increased carbon availability, disease suppressiveness, nematode richness and diversity, the stability and maturity of the food web, and microbial activity and functional diversity. Organic matter addition played a weaker role in enhancing soil quality, possibly due to the range of composition of the organic matter inputs used in the LTEs. POXC was the indicator that discriminated best between soil management practices, followed by nematode indices based on functional characteristics. Structural equation modeling shows that POXC has a central role in nutrient retention/supply, carbon sequestration, biodiversity conservation, erosion control and disease regulation/suppression. The novel indicators proposed here have great potential to improve existing soil quality assessment schemes. Their feasibility of application is discussed and needs for future research are outlined.  相似文献   

20.
Kelps are highly productive seaweeds found along most temperate latitude coastlines, but the fate and importance of kelp production to nearshore ecosystems are largely unknown. The trophic role of kelp-derived carbon in a wide range of marine organisms was assessed by a natural experiment. Growth rates of benthic suspension feeders were greatly increased in the presence of organic detritus (particulate and dissolved) originating from large benthic seaweeds (kelps). Stable carbon isotope analysis confirmed that kelp-derived carbon is found throughout the nearshore food web.  相似文献   

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