scholarly journals Seasonal change in light partitioning among coexisting species of different functional groups along elevation gradient in subalpine moorlands

2014 ◽  
Vol 204 (4) ◽  
pp. 913-923 ◽  
Author(s):  
Chiho Kamiyama ◽  
Shimpei Oikawa ◽  
Kouki Hikosaka
2021 ◽  
Vol 1 ◽  
Author(s):  
Minxia Liu ◽  
Bowen Li ◽  
Lu Xu ◽  
Ruixin Yu

Potentilla fruticosa is a typical shrub of alpine meadows with canopy effects that can greatly influence soil fertility and microbiological parameters. Changes in rhizosphere microorganisms can reflect the response of these plants to environmental changes. This study aimed to examine the rhizosphere and non-rhizosphere of P. fruticosa on the amount of selected microorganisms and main environmental factors at different elevation gradients (3,000, 3,250, 3,500, 3,750, and 4,000 m). The results suggested that bacteria were predominant of the microbial soil community in the rhizosphere and non-rhizosphere, while fungi and actinomycetes represented the minority. With the increase of altitude, the total amount of microbial, bacteria, and actinomycetes in the rhizosphere and non-rhizosphere of P. fruticosa showed a downward trend, and microbial functional groups showed that the “hump shape” changed, but the fungi showed the opposite. Variance inflation factor (VIF) screening environmental factors and path analysis were obtained. In the rhizosphere soil, bacteria were affected by Soil organic carbon (SOC), and soil bulk density (SBD) became the main environmental limiting factor with the increase of altitude. The main environmental limiting factor of actinomycetes changed from SBD to Soil total (ST). In the non-rhizosphere soil, the bacteria and actinomycetes changed from ST to SOC and SBD, respectively. The main environmental limiting factor of the fungi was SOC in the rhizosphere and non-rhizosphere. Soil water content (SWC) was the main environmental determinant factor for all microbial groups, microbial functional groups were related to Soil total nitrogen (STN). Our results help to understand the relationship between nutrient cycling and the ecosystem function of alpine meadow plant soil microorganisms and provide theoretical support for alpine meadow ecosystem restoration, biodiversity protection, and the use of microbial resources.


1971 ◽  
Author(s):  
Warren G. Bennis ◽  
Michael Beer ◽  
Gerald R. Pieters ◽  
Alan T. Hundert ◽  
Samuel H. Marcus ◽  
...  

2016 ◽  
Vol 19 (2) ◽  
pp. 93-100
Author(s):  
Lalita El Milla

Scaffolds is three dimensional structure that serves as a framework for bone growth. Natural materials are often used in synthesis of bone tissue engineering scaffolds with respect to compliance with the content of the human body. Among the materials used to make scafffold was hydroxyapatite, alginate and chitosan. Hydroxyapatite powder obtained by mixing phosphoric acid and calcium hydroxide, alginate powders extracted from brown algae and chitosan powder acetylated from crab. The purpose of this study was to examine the functional groups of hydroxyapatite, alginate and chitosan. The method used in this study was laboratory experimental using Fourier Transform Infrared (FTIR) spectroscopy for hydroxyapatite, alginate and chitosan powders. The results indicated the presence of functional groups PO43-, O-H and CO32- in hydroxyapatite. In alginate there were O-H, C=O, COOH and C-O-C functional groups, whereas in chitosan there were O-H, N-H, C=O, C-N, and C-O-C. It was concluded that the third material containing functional groups as found in humans that correspond to the scaffolds material in bone tissue engineering.


2019 ◽  
Author(s):  
Federico Morelli ◽  
Yanina

ContextThe negative association between elevation and species richness is a well-recognized pattern in macro-ecology. ObjectivesThe aim of this study was to investigate changes in functional evenness of breeding bird communities along an elevation gradient in Europe. MethodsUsing the bird data from the EBCC Atlas of European Breeding Birds we estimated an index of functional evenness which can be assumed as a measure of the potential resilience of communities.ResultsOur findings confirm the existence of a negative association between elevation and bird species richness in all European eco regions. However, we also explored a novel aspect of this relationship, important for conservation: Our findings provide evidence at large spatial scale of a negative association between the functional evenness (potential community resilience) and elevation, independent of the eco region. We also found that the Natura2000 protected areas covers the territory most in need of protection, those characterized by bird communities with low potential resilience, in hilly and mountainous areas.ConclusionsThese results draw attention to European areas occupied by bird communities characterized by a potential lower capacity to respond to strong ecological changes, and, therefore, potentially more exposed to risks for conservation.


1996 ◽  
Vol 451 ◽  
Author(s):  
T. Shimizu ◽  
M. Murahara

ABSTRACTA Fluorocarbon resin surface was selectively modified by irradiation with a ArF laser beam through a thin layer of NaAlO2, B(OH)3, or H2O solution to give a hydrophilic property. As a result, with low fluence, the surface was most effectively modified with the NaAlO2 solution among the three solutions. However, the contact angle in this case changed by 10 degrees as the fluence changed only 1mJ/cm2. When modifying a large area of the surface, high resolution displacement could not be achieved because the laser beam was not uniform in displacing functional groups. Thus, the laser fluence was successfully made uniform by homogenizing the laser beam; the functional groups were replaced on the fluorocarbon resin surface with high resolution, which was successfully modified to be hydrophilic by distributing the laser fluence uniformly.


2019 ◽  
Author(s):  
Marharyta V. Laktsevich-Iskryk ◽  
Nastassia A. Varabyeva ◽  
Volha V. Kazlova ◽  
Vladimir N. Zhabinskii ◽  
Vladimir A. Khripach ◽  
...  

In this article, we report a photocatalytic protocol for the isomerization of 1,2-disubstituted cyclopropanols to linear ketones. The reaction proceeds <i>via</i> radical intermediates and tolerates various functional groups.


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