蚯蚓野外采样方法评述

蚯蚓作为土壤生态系统的关键组成部分,不但可以改善土壤结构,而且与许多生物化学养分循环直接相关,对土壤质量改善和土壤生产力提高起到至关重要的作用.然而,蚯蚓野外采样方法的系统研究和评估还比较缺乏,在国内尤其少见.本文综述了目前国内外常见蚯蚓野外采样方法的操作过程、优缺点、有效性以及对蚯蚓种群特征研究结果可能产生的影响,认为在允许扰动土壤的区域,利用驱虫剂与手拣法相结合进行蚯蚓采样能够较为准确地反映蚯蚓种群和生物量的真实特征;在不能扰动土壤的区域异硫氰酸烯丙酯(AITC)溶液方法是最佳选择.     

蚯蚓野外采样方法评述

蚯蚓作为土壤生态系统的关键组成部分,不但可以改善土壤结构,而且与许多生物化学养分循环直接相关,对土壤质量改善和土壤生产力提高起到至关重要的作用.然而,蚯蚓野外采样方法的系统研究和评估还比较缺乏,在国内尤其少见.本文综述了目前国内外常见蚯蚓野外采样方法的操作过程、优缺点、有效性以及对蚯蚓种群特征研究结果可能产生的影响,认为在允许扰动土壤的区域,利用驱虫剂与手拣法相结合进行蚯蚓采样能够较为准确地反映蚯蚓种群和生物量的真实特征;在不能扰动土壤的区域异硫氰酸烯丙酯(AITC)溶液方法是最佳选择.     

长白山杨桦林不同蚯蚓类群对电击采样的响应及其影响因素

电击法采集蚯蚓对环境相对友好,但电击效率可能因立地条件和蚯蚓类群而变化,进而限制了电击法的广泛应用。本研究于2017年11月上旬采用电击法配合手拣法对长白山3个不同森林发育阶段的杨桦林的蚯蚓群落进行了调查,分析了森林发育阶段、蚯蚓生态型、蚯蚓种群大小以及发育阶段、土壤温湿度状况等对电击效率的影响。结果表明:不同森林发育阶段蚯蚓的电击效率不同,其中40年生杨桦林电击效率最高,其蚯蚓数量和生物量电击效率分别为68.5%和57.4%;表栖型的诺登爱胜蚓(Eisenia nordenskioldi)活动能力最强,电击效率高达100%;内-深栖型的长白山杜拉蚓(Drawida changbaishanensis)在实验期间处于蜷曲休眠状态,电击效率低至0;而内栖型的安德爱胜蚓(Eisenia andrei)的电击效率为22.2%～58.3%;安德爱胜蚓种群大小与电击效率无明显的相关关系(其中,数量:r=0.139,P=0.381,生物量:r=0.025,P=0.877);安德爱胜蚓成体的电击效率显著高于幼体(P=0.014);土壤温度对电击效率有显著的影响,当土壤温度低于6℃时电击效率为0;当土...     

不同蚯蚓采样方法对比研究

蚯蚓种类组成和丰度变化是反映农业管理措施对土壤质量影响的重要指标。为研究利用芥末悬液等方法进行蚯蚓样品采集的有效性和准确性,寻求合理有效的蚯蚓种群特征调查方法,在我国东北玉米连作黑土上分别运用手拣法、福尔马林溶液驱赶法、芥末+水悬液及芥末+乙酸悬液驱赶法,以及驱虫剂与手拣法相结合的方法进行蚯蚓样品采集,将上述7种方法测得的蚯蚓丰度、生物量及年龄组成信息进行了系统分析。结果表明,福尔马林溶液驱赶法不结合手拣法使用时测得的蚯蚓丰度及生物量远远低于其他方法,尤其幼年蚯蚓比例偏低,并不能反映真实的蚯蚓种群特征。使用芥末悬液做驱虫剂有效性明显提高,尤其芥末+乙酸悬液,测得的蚯蚓丰度比手拣法高22.3%。福尔马林溶液结合手拣法后有效性大大提高,测得的蚯蚓丰度和生物量分别是其单独使用时的19.1和9.3倍,但相对其他驱虫剂方法仍高估了成年蚯蚓的比例;芥末+水悬液和芥末+乙酸悬液方法结合手拣法后收集到蚯蚓的数量分别提高了67.8%和89.1%,平均个体重量分别是原来的1.8和1.3倍,说明芥末悬液不会杀死小个体的幼年蚯蚓,但少部分大个体蚯蚓及洞穴不与地表相接的蚯蚓可能并不能被其驱赶至地表,结合手拣法后可以弥补这个缺陷。芥末+乙酸悬液结合手拣法收集到的成年及幼年蚯蚓数量和生物量均显著高于其他方法(P<0.05),既能有效地驱赶小个体和幼年蚯蚓,又可以收集到洞穴不与地表相接的土栖型蚯蚓,因此可以作为真实有效地反映蚯蚓种群特征的采样方法之一。     

蚯蚓在生态系统中的作用

蚯蚓能够对许多决定土壤肥力的过程产生重要影响, 被称为“生态系统工程师”。它通过取食、消化、排泄和掘穴等活动在其体内外形成众多的反应圈, 从而对生态系统的生物、化学和物理过程产生影响。蚯蚓在生态系统中既是消费者、分解者, 又是调节者, 它在生态系统中的功能具体表现在: (1) 对土壤中有机质分解和养分循环等关键过程的影响; (2) 对土壤理化性质的影响; (3) 与植物、微生物及其他动物的相互作用。蚯蚓活动及其在生态系统中的功能受蚯蚓生态类群、种群大小、植被、母岩、气候、时间尺度以及土地利用历史的综合控制。蚯蚓外来种入侵与生态系统的关系以及蚯蚓对全球变化的响应和影响是两个值得关注的问题。土壤本身的复杂性, 蚯蚓自然历史和生物地理学知识的缺乏, 野外控制蚯蚓群落方法的滞后等都限制了蚯蚓生态学的发展。其他新技术如研究养分循环的碳氮同位素分析和揭示土壤微结构的图像分析等技术的应用是蚯蚓生态功能研究的迫切需要。     

使用陷阱采样在蜘蛛生态学研究中的应用

介绍1种国外常用的研究地面活动蛛知生态学的采样的方法，即陷阱采样。对如何制作和排布陷阱做了比较详细的说明，并对使用陷阱研究的生境以及通过陷阱所获得的类群做了介绍，同时，通过举例对如何使用陷阱及由陷阱得到的数据的数学处理作了说明。     

蚯蚓在环境安全研究中的应用

蚯蚓在环境污染的生态毒理学诊断方面具有重要生态学意义,这是蚯蚓在环境安全研究中应用的基础。本文概述了蚯蚓生态毒理诊断的一些试验方法,包括急性毒性试验法、田间生态毒性试验法、污染环境的生物检测法和微观生物指标检测法。在这基础上,就蚯蚓的环境安全生态指示研究进展进行了剖析与展望。还从蚯蚓处理生活垃圾与农业有机废弃物以及污水的蚯蚓过滤处理等应用方面,论述了蚯蚓在污染环境解毒过程中的重要生态作用及今后的发展方向。     

蚯蚓在我国南方土壤修复中的应用

蚯蚓作为生物量最大的土壤动物, 对土壤生态系统和环境质量影响深远。本研究介绍了华南地区主要应用的皮质远盲蚓(Amynthas corticis)、毛利远盲蚓(A. morrisi)、壮伟远盲蚓(A. robustus)、参状远盲蚓(A. aspergillum)、南美岸蚓(Pontoscolex corethrurus)和赤子爱胜蚓(Eisenia fetida)的生态特征, 阐述了它们与土壤pH值、酶活性、金属富集和有效性改变、孔道和微团聚体形成之间的紧密关系: (1)蚯蚓生存的土壤酸碱性范围较广(pH为3.8-7.9), 其存活率与土壤类型、有机质含量和成分、土壤污染程度和蚯蚓种类相关; (2)肠道内、蚓粪和蚓触圈的酶活性分别表征了蚯蚓取食喜好、土壤养分循环及微生物种群特征; (3)蚯蚓能够富集不同种类的金属并改变其有效性, 这些变化具有蚓种间、金属种类间和土壤类型之间的差异; (4)蚯蚓活动及其生产的蚓粪能改变土体结构、产生孔道、影响土壤团聚体数量、大小和分布。蚯蚓的上述作用使其在解决中国南方红壤酸化、土壤金属污染、茶园土壤养分不平衡、高速公路建设临时用地土壤损毁等方面具有广阔的应用前景。目前, 由于华南远盲蚓的生理特征差异研究较少, 远盲蚓繁育技术的缺乏一定程度上限制了这些蚯蚓在中型和大型尺度下应用技术的研究和推广。有必要进一步挖掘蚯蚓在土壤修复中的潜力, 进行蚯蚓主导的相关技术研发, 深入探讨其影响机制。     

蚯蚓在重金属污染土壤生物修复中的应用潜力

综述了不同生态类型的蚯蚓的特性及其土壤生态功能;总结了其对土壤重金属富集和有效性的作用及影响重金属活化的机理,并指出目前相关的生物化学机理研究的不足及其未来研究方向.同时,文章针对蚯蚓在农业和环境领域的应用现状,提出其应用于重金属污染土壤的植物提取技术的可能性,在未来工作中应加强真实污染土壤室内模拟和田间试验研究,进一步探索筛选和繁育本地蚯蚓品种以及添加有机物等相关技术.     

蚯蚓生物标记物在土壤生态风险评价中的应用

蚯蚓在土壤中行使了很多重要的生态功能,蚯蚓生物标记物常用作土壤污染风险评价研究。这篇综述的目的是探讨当前蚯蚓生物标记物研究是否可以应用到实际的土壤污染风险评价。1)讨论了蚯蚓生物标记物在土壤污染风险评价体系中的重要性,认为它是化学分析方法的有益补充,可以提供更为全面和客观的土壤污染信息;2)综述了相关研究中所使用的蚯蚓类型,土壤类型和生物标记物类型,及其它试验设计要素和最后结果的变异,认为目前蚯蚓生物标记物研究以实验室基础研究为主,筛选出了大量的生物标记物,一定程度上揭示了生物标记物的对各类典型污染物及其组合的应答机制;同时也认为,未来的蚯蚓生物标记物研究应该重点探讨将其应用到实际的土壤污染风险评价中的可行性及如何应用;3)目前不同研究之间从试验设计到结果都具有很大的变异,难以通过综合比较获得完全可靠的具有实践意义的结论和成果,因此,有必要通过建立标准化的蚯蚓生物标记物研究方法,推动生物标记物的研究工作;4)提出了蚯蚓生物标记物研究方法标准化的具体建议,推荐了蚯蚓生物标记物走向实际应用所需要解决的问题。     

Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods

Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure, application of this sampling device provides absolute estimates of the populations of arthropods as numbers per standardized sampling area. The sampling efficiency depends critically on the sampling duration. In a mature rice crop, a two-minute sampling in an enclosure of 0.13 m² yields more than 90% of the arthropod population. The device also allows sampling of arthropods dwelling on the water surface or the soil in rice paddies, but it is not suitable for sampling fast flying insects, such as predatory Odonata or larger hymenopterous parasitoids. The modified blower-vac is simple to construct, and cheaper and easier to handle than traditional suction sampling devices, such as D-vac. The low cost makes the modified blower-vac also accessible to researchers in developing countries.     

An Evaluation of Plotless Sampling Using Vegetation Simulations and Field Data from a Mangrove Forest

In vegetation science and forest management, tree density is often used as a variable. To determine the value of this variable, reliable field methods are necessary. When vegetation is sparse or not easily accessible, the use of sample plots is not feasible in the field. Therefore, plotless methods, like the Point Centred Quarter Method, are often used as an alternative. In this study we investigate the accuracy of different plotless sampling methods. To this end, tree densities of a mangrove forest were determined and compared with estimates provided by several plotless methods. None of these methods proved accurate across all field sites with mean underestimations up to 97% and mean overestimations up to 53% in the field. Applying the methods to different vegetation patterns shows that when random spatial distributions were used the true density was included within the 95% confidence limits of all the plotless methods tested. It was also found that, besides aggregation and regularity, density trends often found in mangroves contribute to the unreliability. This outcome raises questions about the use of plotless sampling in forest monitoring and management, as well as for estimates of density-based carbon sequestration. We give recommendations to minimize errors in vegetation surveys and recommendations for further in-depth research.     

Long Term Measurement of the Trans-Root Electric Potential in a Persimmon Tree in the Field

kaki tree (Diospyros kaki, Japanese persimmon), which showed clear diurnal oscillation throughout two successive years. The level of the TRP on the average for every ten days had two minima (ca. –70 mV) in mid winter and mid summer, and two maxima (ca. –30 mV) in October and May. A regular seasonal change in the amplitude of the oscillation was observed; it was at its maximum (ca. 70 mV) in early spring just before the sprouting of new leaves, and at its minimum (ca. 10 mV) during summer and early autumn when leaves were fully expanded. The relationship between the TRP, water transport and rainfall is discussed. Received 18 February 1998/ Accepted in revised form 8 November 1998     

蚯蚓纤溶酶底物特异性

蚯蚓纤溶酶是具有较强溶栓作用的丝氨酸蛋白酶,为研究蚯蚓纤溶酶在溶栓的同时是否对其他血液蛋白有破坏作用,本实验以一些血液功能蛋白为底物,用蚯蚓纤溶酶在体外对其进行水解,采用SDS—PAGE检测水解前后底物成分的变化。结果显示,蚯蚓纤溶酶短时间内能完全水解纤维蛋白和纤维蛋白原,长时间作用下能部分水解牛血清白蛋白和人免疫球蛋白重链,不水解牛血红蛋白、牛血超氧化物歧化酶和牛凝血酶原。表明蚯蚓纤溶酶对血栓成分具有较强的识别和水解能力,而对其他血液蛋白作用微弱,说明蚯蚓纤溶酶作为药物使用时具有较强的溶栓和预防血栓形成的作用,且副作用较小。     

恒定磁场对苦荞种子的生物学效应

本试验用不同剂量的恒定磁场处理苦荞种子,结果表明：适宜的磁场可有效地提高苦荞种子萌发期的发芽势、发芽率,降低种子浸出液的电导率。     

The Eukaryotic Tree of Life from a Global Phylogenomic Perspective

Molecular phylogenetics has revolutionized our knowledge of the eukaryotic tree of life. With the advent of genomics, a new discipline of phylogenetics has emerged: phylogenomics. This method uses large alignments of tens to hundreds of genes to reconstruct evolutionary histories. This approach has led to the resolution of ancient and contentious relationships, notably between the building blocks of the tree (the supergroups), and allowed to place in the tree enigmatic yet important protist lineages for understanding eukaryote evolution. Here, I discuss the pros and cons of phylogenomics and review the eukaryotic supergroups in light of earlier work that laid the foundation for the current view of the tree, including the position of the root. I conclude by presenting a picture of eukaryote evolution, summarizing the most recent progress in assembling the global tree.It is redundant to say that eukaryotes are diverse. Plants, animals, and fungi are the charismatic representatives of the eukaryotic domain of life, but this narrow view does not do justice to the eukaryotic diversity. Microscopic eukaryotes, often unicellular and known as the protists, represent the bulk of most major groups, whereas multicellular lineages are confined to small corners on the global tree of eukaryotes. If all eukaryotes possess structures enclosed within intracellular membranes (the organelles), an infinite variation of forms and feeding strategies has evolved since their origin. Eukaryotic cells can wander on their own, sometimes forming hordes of free-living pico-sized organisms that flourish in oceans. They can be parasites or symbionts, or come together by the billions in tightly packed, highly regulated multicellular organisms. Eukaryotes have occupied just about every ecological niche on Earth. Some actively gather food from the environment, others use plastids (chloroplasts) to derive energy from the light; many can adapt to variable conditions by switching between autotrophy and the predatory consumption of prey by phagotrophy. Eukaryotes also show a great deal of genomic variation (Lynch and Conery 2003). Some amoebozoan protists, for instance, have the largest known genomes—more than 200 times larger than that of humans (Keeling and Slamovits 2005). Conversely, microbial parasites can have highly compact, bacterial-size genomes (Corradi et al. 2010). Even smaller are the remnant nuclear genomes (nucleomorphs) of what were once free-living microbial algae. At around 500,000 nucleotides and hardly encoding a few hundreds genes, nucleomorphs are the smallest nuclear genome of all (Douglas et al. 2001; Gilson et al. 2006; Lane et al. 2007).Recognizing this great diversity and pushed by a desire to establish order, biologists have long attempted to assemble a global eukaryotic tree of life. A fully resolved phylogenetic tree including all organisms is not only the ultimate goal of systematics, it would also provide the foundation to infer the acquisition and evolution of countless characters through the history of long-dead species. But early attempts to resolve the eukaryotic tree, most of which were based on comparisons of morphology and nutrition modes, faced the impossible challenge of describing in an evolutionary sensitive way a world in which most of the diversity occurs among tiny microbes. For decades, biology textbooks assigned the eukaryotes to evolutionary entities called “kingdoms” in which the lords were the animals, plants, and fungi (Copeland 1938; Whittaker 1969; Margulis 1971). This is not to say that biologist ignored protists, and they have been in fact recognized as a kingdom for more that a century (Haeckel 1866), but protists were considered to be "simple" organisms from which more elaborate, multicellular species emerged. Although these early proposals succeeded in recognizing several major assemblages, such as animals and plants, they were less successful in resolving the relationships between the groups and, with the benefit of hindsight, failed to account for the fundamental paraphyletic and complex nature of the protist lines.     

汉坦病毒空气传播感染的实验室和野外采样研究

本项研究是通过动物实验和现场采样研究汉坦病毒气溶胶传播感染。用感染的黑线姬鼠排泄物自然形成的病毒气溶胶进行实验。黑线姬鼠感染后第5天放入离乳小鼠和乳小鼠,暴露10?d,检测不到抗体,感染后第7天,放入离乳小鼠和乳小鼠,暴露10?d,可以检测出抗体;黑线姬鼠在暴露15?d时,可以检测出抗体。可见黑线姬鼠感染后,第7天可能是它向体外排毒的一个时间标志,且形成的病毒气溶胶具有感染性。对现场采集的空气样品和收集的打谷者佩戴的口罩样品的研究发现,在稻田堆放的稻捆根部和鼠栖息的草窝的空气中每350L空气中和打谷场脱粒机附近每96L空气中,含有至少一个具有生物活性的汉坦病毒粒子。结合流行病学调查结果,可以判定,汉坦病毒经空气传播吸入感染可能是秋冬季节肾综合征出血热发病的主要传播途径。     

汉坦病毒空气传播感染的实验室和野外采样研究

本项研究是通过动物实验和现场采样研究汉坦病毒气溶胶传播感染。用感染的黑线姬鼠排泄物自然形成的病毒气溶胶进行实验。黑红姬鼠感染后第5天放入离乳小鼠和乳小鼠,暴露10d,检测不到抗体,感染后第7天,放 乳小鼠和乳小鼠,暴露10d,可以检测出抗体;黑线姬鼠在暴露15d时,可以检测出抗体,可见黑线姬鼠感染后,第4天可能是它向体外排毒的一个时间标志,且形成的病毒气溶胶具有感染性。对现场采集的空气样品和收集的打谷者佩戴的口罩样品的研究发现,在稻田堆放的稻捆根部和鼠栖息的草窝的空气中每350L空气中和打谷场脱粒机附近每96L空气中,含有至少一个具有生物活性的汉坦病毒粒子,结合流行病学调查结果,可以判定,汉坦病毒经空气传播吸入感染可能是秋冬季节肾综合征出血热发病的主要传播途径。     

Improving the Accuracy of Sampling Field Plots for Plant-Parasitic Nematodes

The validity of nematode data from field experiments depends largely on how well samples represent the nematode population. Data from an intensive sampling of three field plots before and after spring cultivation were used to compare eight simulated sampling schemes. Average deviation from the plot mean ranged from 10% to 34% before cultivation and from 7% to 16% after cultivation. Samples taken from only the plant row erred most before cultivation but were comparable to other schemes after cultivation. Several schemes achieved a 25% deviation or less in 90% of the sample simulations. Sampling a nematode population usually involves subsampling a composite bulk sample, however, and this increases error by an estimable amount. A random sample with 35 cores and four random subsamples estimated mean plot densities within 25% with probabilities ranging from 0.77 to 0.85. The probability of a sample-subsample combination coming within a specified percent error of the true mean can be extended cautiously to any field mean and variance more-or-less independent of species and area using formulae presented herein. The most economical method of increasing sample accuracy was to increase the number of soil cores.     

蚓激酶研究进展

蚓激酶是一种新型的溶栓制剂,具有良好的溶血栓治疗效果。综述了至今为止分离到的蚓激酶成分、生物学活性、药物学作用、抑制剂和空间结构分析等方面的研究进展 。