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音量 9, 問題 1 (2021)


Functional and phylogenetic temporal turnover in two temperate forests in Northeast China

Zhanqing Hao

Whether deterministic or stochastic processes dominate temporal turnover of community composition and which factor has significant influence on that turnover, has been a central challenge in community ecology. Functional and phylogenetic temporal beta diversity can capture important insights of the underlying processes. In this study, we focus on functional temporal turnover based on 14 functional traits and phylogenetic temporal turnover using fully mapped data in two large temperate forest plots at different successional stage. We found that 1) Deterministic processes are the main process for both forests and size classes. The functional and phylogenetic compositions are relatively constrained at late successional stage and changed dynamically at early successional stage.

In young-growth forest, useful and phylogenetic temporal changes were basically higher than expected for all trees, small trees, and large trees. Conversely, in the old-growth forest, useful and phylogenetic material changes were lower than expected for all trees, but opposite marking were found for two size classes; i.e., change was elevated than expected for large trees and lower than expected for small trees. BRT models showed that the most influential factors underlying the temporal change of all trees shifted from abiotic (e.g., topography) to biotic (e.g., basal area) factors with increasing succession phase. Regardless of successional phase, the suitable factors changed from abiotic factors for small trees to biotic factors for large trees.

The purpose of this study are to detect (1) the relative consequence of deterministic vs. stochastic process in driving the functional and phylogenetic material changes at different successional stages and tree size classes in temperate forests and (2) the relative effective of abiotic vs. biotic factors on temporal change.

Moreover, the functional and phylogenetic turnover of two size class trees have contrary tendency at different succession stage, which may be due to the similarities among death, recruitment and survival individuals. 2) Principal components and null model analysis showed that functional traits that are more related to “nutrient economy” and structure investment can significantly influence the temporal turnover; 3) Biotic factors (e.g.. basal area of neighborhood) play an important role in influencing functional and phylogenetic temporal turnover for both forest plot. In conclusion, our analysis clearly emphasizes the functional and phylogenetic temporal turnover are deterministic at local scale. In addition, identification of key functional traits are important for functional diversity analysis, which can contribute to a better understanding of local community assembly mechanisms.

Temporary change in community composition outcome from a combination of immigration and local demographic dynamics . The dynamics depend on stochastic processes and on how survival and reproduction are over blown by environmental factors and biotic interactions over time Characterizing the temporal swap of community composition can thus give insights into fundamental assembly processes. Many studies in community ecology focus at inferring assembly processes from the spatial structure of communities at a given time , but they miss how configuration at a given time can influence subsequent dynamics, especially when biotic inter linkage are at play. Although space-for-time replacement considers different temporal stages of community dynamics allocated in space, it does not acknowledge how assembly depends on previous community states.

Deterministic procedures govern tree functional and phylogenetic material changes, and the underlying deterministic processes change from habitat filtering to biotic interaction over succession and with growing tree size.


Cumulative impact assessment as a key conservation planning tool: An application on Posidonia oceanica meadows in Greek waters of the Aegean Sea

Vassiliki Vassilopoulou

Cumulative consequences assessment is a computational tool for calculating and visualizing the consequences of a combination of pressures effect by human activities on ecosystem components. It is a fundamental process in Conservation Planning and Marine Spatial organizing efforts based on an Ecosystem-Based Approach. For assessing the sum of impacts on ecosystem components, a well-developed approach that takes into consideration the presence/absence grid data of human activities and ecosystem components has been used. This approach requires a thorough knowledge of human activities (intensity, location) and ecosystem components (i.e. vulnerability, resilience) to assess their collective impacts. In this study, a key ecosystem component for the Mediterranean, the Posidonia oceanica meadows, has been selected aiming to identify areas where the status of this priority habitat is threatened and hence deserve the attention of the management authorities. As a first step, geospatial data of human activities and existing management measures were collected and processed.

Effective ecosystem-based management requisite understanding ecosystem retaliation to multiple human threats, rather than focusing on single threats. To recognize ecosystem reaction to anthropogenic threats holistically, it is compulsory to know how threats affect various components within ecosystems and ultimately alter ecosystem functioning. We used a case study of a Mediterranean seagrass (Posidonia oceanica) food web and specialist knowledge elicitation in an application of the beginning steps of a framework for assessment of aggregate human impacts on food webs. We produced a conceptual seagrass food web model, set on the primary trophic relationships, identified the main threats to the food web components, and assessed the elements' vulnerability to those threats.

An impact score representing the per-pixel (1 km*1 km cell) average of Posidonia oceanica meadows vulnerability-weighted stressor intensities was calculated and mapped. According to the impact score, the total pressure on this ecosystem component was very low (79.8%) in the vast majority of the area where Posidonia oceanica extends (Figure 1). However, certain locations where the exerted pressures on sea grasses seemed to be rather high were identified in the sea regions of Chalkidiki, Attica, Southern Aegean Sea and Crete. These pressures appeared to be mainly connected to drivers such as small scale fishing, urbanization, ports and agricultural run-off. The latter suggest that aside from truly marine activities (e.g. small scale fishing), the importance of land sea interactions is also crucial for determining the status of coastal ecosystems.


Vassiliki Vassilopoulou (PhD) is a Research Director at Hellenic Centre for Marine Research, Greece. She is involved in research works in the field of ecosystem formed fisheries management. Since 2009, she has been occupied in Maritime Spatial Planning research issues through her implication in several EU projects. In the last years, she is also working on issues related to the development of a more structured interface between policy needs and scientific advice through interaction with key stakeholders. She has proceed as chairperson or moderator, and/or was an invited speaker, in sessions dedicated to topics of her proficiency in international conferences and workshops, and has been giving pertinent postgraduate presentation in the Universities of Athens and Thessaloniki. She is member of International Scientific Committees and has recently joined the Commission on Ecosystem Management (CEM) of the IUCN. She has more than 150 publications and presentations in international scientific journals and conferences.



Sandeep Kumar Srivastava

There is a frantic race to escalate the storage density of hard disk drive (HDD) due to its vast applications. The recording media utilized for making conventional HDD is made up of varied layers thin film or magnetic alloys, which naturally forms nanometer-scale grains and every recorded bit is kept across hundreds of these magnetic grains. Although, the conventional perpendicular media is being used in present recording technology, but it is expected to drop its fuel in next few years due to a circumstances called super-paramagnetism (thermal stability of recorded bit). Newly, one alternative potential way has been proposed, so known as bit patterned media (BPM). Bit Patterned Media (BPM) for magnetic recording supply a way to densities $>1 Tb/in^2$ and circumvents numbers of the challenges connected with conventional granular media technology. Instead of recording a bit on an ensemble of random grains, BPM uses an arrangement of lithographically defined isolated magnetic islands, each of which kept one bit. Manufacture of BPM is viewed as the significant and big challenge for its commercialization. In this article we explained a BPM manufacture method which combines e-beam lithography, directed self-assembly of block copolymers, self-aligned double patterning, nanoimprint lithography, and ion milling to give rise to BPM based on CoCrPt alloys.

In such bit patterned media, every artificially fabricated magnetic nanostructure can kept an individual bit rather than utilizing hundreds of naturally formed small grains to store single bit. Ordered arrays of isolated magnetic nanostructures are of appreciable interest to escalate the storage density of hard disks beyond the present perpendicular media. In such bit patterned media (BPM), every artificially fabricated magnetic nanostructure can store a particular bit.

We advanced a novel non-lithographic technique to fabricate perpendicularly magnetized BPM system and we observed Co/Pt bit pattern media.

In present talk, the author will check out few results on Co/Pt

bit pattern media, as well as results on CoTb alloysbased bit patterned media. This amalgamation of fabrication technologies attains feature sizes of $<10 nm$, significantly smaller than what conventional semiconductor nanofabrication technique can achieve.  

The advantages of rectangular bits are analyzed from a theoretical and modeling point of view, and system integration requirements such as servo patterns, implementation of write synchronization, and providing for a stable head-disk interface are addressed in the context of experimental results. Optimization of magnetic alloy materials for thermal stability, writeability, and switching field distribution is discussed, and a new method for growing BPM islands on a patterned template is presented.

These materials were manufactured using the barrier layer of auto-assembled anodic alumina template (a non-lithographic method) and by depositing either CoPt multilayers or CoTb alloy to shape an ordered array of ferromagnetic nanodots, so-called nanobumps. We used remarkable hall resistance quantification to probe magnetization reversal mechanism and switching field distribution. The role of interdot exchange coupling and dipolar coupling, magnetization reversal procedure will be discussed.


The urban forest: Created biodiversity

Charles A Wade

The urban forest is much more various than any surrounding natural forest in numerous parts of the United States. This “Created Biodiversity” is the result of the continuous introduction of new tree species to the urban forest. The three main driving forces behind this urban biodiversity are: alternatives of people (based primarily on socioeconomic factors and the preference to plant “something different” in their yards), the heterogeneity of urban habitats where we have set up many new and various habitats that are not necessarily natural environments for indigenous tree species, and the introduction of non-indigenous species which are sometimes potentially invasive and conduct to a change in the natural tree structure of the city. This created biodiversity is not a natural assemblage of tree species, but a makeshift company based on human desires and choices. A survey of the urban forest was managed in 1980 in ten selected Midwest, USA cities. The survey was then reproduced in six of these cities. The urban forest company was then compared to natural forests in the locality of the original cities surveyed. It was found that the species richness was much significant in the cities, with 47 to 82 species, than the natural forests in the vicinity area of those surveyed cities which only had 18 to 23 species.

Efforts at diminishing global biodiversity loss have often focused on preserving huge, intact natural habitats. However, preserving biodiversity should also be an important target in the urban environment, peculiarly in highly urbanized areas where little natural habitat remains. Escalating, research at the city/county scale as well as at the landscape scale disclose that urban areas can contain relatively high levels of biodiversity. Important percentages of species found in the vicinity natural habitat, including endangered species, have been found in the urban forest.This contribution laconic highlights some examples of urban biodiversity research from different areas of the world.

Key issues involved in understanding the motif and processes that affect urban biodiversity, such as the urban–rural gradient and biotic homogenization, are labeled. The potential for urban areas to harbor considerable sum of biodiversity needs to be recognized by city planners and urban foresters so that regulation practices that preserve and encourage that diversity can be pursued. Management alternative should focus on increasing biodiversity in all feature of the urban forest, from street trees to urban parks and woodlots.

In an urban ecosystem, the anthropogenic methods of vegetation dynamics was started from top landuse change to nursery trade and urban design, whereas the bottom-up anthropogenic forces were consider at a household scale of landscaping aesthetics and socioeconomics. In the past two decades, a number of factors have been inspected to influence urban forest diversity, such as neighborhood age and group affluence, the portion of immigrants , local stakeholders, different management regimes, residents' income  and exotic trees contribution. However, due to the problem of biodiversity itself and its interactions with human activities, the driving factors is not always the similar everywhere or every time.


Functionalized carbon nanotubes by direct liquid injection chemical vapor deposition method as CO2 sensor

B C Yadav

In the current work we have described the synthesis and characterization of Multiwall Carbon Nanotube (MWCNT) formed thin film and its implementation as a CO2 gas sensor. The MWCNT was assembled by Direct Liquid Injection Chemical Vapor Deposition method (DLICVD) make use of ethanol as a precursor in the existence of argon gas atmosphere and furnace temperature at 750 oC. The experimental set-up is shown in Figure-1. The apparatus consists of a (5×100 cm) cylindrical quartz tube provided one end with a bond for a vacuum system and for the injection of gas carrier  (Ar/N2 ) gasses and ethanol vapor at other end. In this procedure, the catalyst particle was developed by chemical reduction of cobalt chloride particle by the sol-gel process. The synthesized cobalt nanoparticle used as a catalyst particle for the growth of CNTs and a thin film such nanoparticles on quartz glass were made by using spin coating technique with revolution rate 1500 rpm for 30 s and then film which is prepared was placed in a hot air oven for 15 minutes at 100 â??.

The thin film of MWCNT was prepared by using spin coating technique and distinguished using scanning electron microscope (SEM), UV-visible spectrometer,X-ray Diffractometer (XRD) and particle size analyzer. The vibrational and rotational spectra were noticed through Fourier Transform Infra-Red Spectroscopy (FTIR) and Raman spectroscopy. The SEM image of the thin film revealed the nanotubelar design grown throughout the surface.

From XRD the minimum crystalline dimension was found to be 14 nm. The optical energy band space of the nanotube-formed thin film was found as 3.6 eV. 

The synthesized CNT-formed thin film was employed for the CO2 sensing. The sensor response of the sensor at room temperature was found as 2.1 and the results were found 98% reproducible. The response and regaining times were create to be 30.2 and 49.6 s, respectively

It is well known that the morphologies, sizes and phases of nanomaterials have great effect on their properties and potential applications. Therefore, the synthesis of nanostructured materials with wanted properties has recently received ample attention. Carbon can be found in several different hybridization states, each having individual properties as shown in Figure 1. In fact, the electrical, thermal, mechanical and chemical effects of the different allotrope forms are directly correlated to their hybridization state and structure, opening up the chance to use the alike material for a vast range of applications .

Several techniques have been reported in the written for the synthesis of 0D, 1D, 2D, and 3D carbon nanomaterials. The most usual techniques are laser ablation, arc-discharge [25,26] and chemical vapor deposition (CVD) . CVD is the most usual employed thin-film toppling technique used to synthesize nanomaterials. Therefore, this review paper will be mainly attentive on the synthesis of novel materials via the CVD technique.

This review paper summarizes the combination of carbon nanomaterials such as fullerenes, carbon nanotubes (CNTs), carbon nanofibers (CNFs), graphene, carbide-derived carbon (CDC), carbon nano-onion (CNO) and MXene via the CVD technique.



Endemic Freshwater Fish Diversity and Habitat Ecology of India

Baliarsingh, Nandi

In the present study, the fish diversity was examined in relation to habitat parameters of water bodies in Jagatsinghpur district, Odisha, INDIA. The samples of water and fish species were collected in summer, rainy and winter seasons from six collection sites from April 2016 to March 2017. A total of 66 species of fishes under 43 genera, 25 families and 9 orders has been recorded. Highest species diversity was observed in the Cyprinidae (28.7%) followed by Bagridae (12.1%). The fish fauna includes 52 Least concern (LC), 3 Near threatened (NT), 2 Data Deficient (DD) and 9 Not Assessed (NA) as per IUCN. The study shows that water bodies of Jagatsinghpur district including numerous economic importance food fishes as well as ornamental fishes belongs to freshwater, marine and brackish water habitat. In the study 46 species coming under capture fishery, 48 species have ornamental value, 19 species for culture and 7 species under sports fishery. The study shows that river and water bodies support considerable diversity of fishes and water quality will be recommended for aquaculture and wildlife propagation. The study will be useful for conservation planning and management and for future assessment after interlinking.


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