scholarly journals Influence of sugarcane growth stages on bird diversity and community structure in an agricultural-savanna environment

Heliyon ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. e06563
Author(s):  
Sifiso M. Lukhele ◽  
Julie Teresa Shapiro ◽  
Themb'alilahlwa A.M. Mahlaba ◽  
Muzi D. Sibiya ◽  
Robert A. McCleery ◽  
...  
Keyword(s):  
Community Structure ◽  
Bird Diversity ◽  
Growth Stages

scholarly journals Vegetation Response to Goats Grazing Intensity in Semiarid Hilly Grassland of the Loess Plateau, Lanzhou, China

2021 ◽  
Vol 13 (6) ◽  
pp. 3569
Author(s):  
Hua Cheng ◽  
Baocheng Jin ◽  
Kai Luo ◽  
Jiuying Pei ◽  
Xueli Zhang ◽  
...  
Keyword(s):  
Growth Rate ◽  
Community Structure ◽  
Plant Growth ◽  
Loess Plateau ◽  
Grazing Intensity ◽  
Gps Tracking ◽  
Growth Stages ◽  
The Loess Plateau ◽  
Vegetation Community ◽  
Natural Grasslands

Quantitatively estimating the grazing intensity (GI) effects on vegetation in semiarid hilly grassland of the Loess Plateau can help to develop safe utilization levels for natural grasslands, which is a necessity of maintaining livestock production and sustainable development of grasslands. Normalized difference vegetation index (NDVI), field vegetation data, and 181 days (one goat per day) of GPS tracking were combined to quantify the spatial pattern of GI, and its effects on the vegetation community structure. The spatial distribution of GI was uneven, with a mean value of 0.50 goats/ha, and 95% of the study area had less than 1.30 goats/ha. The areas with utilization rates of rangeland (July) lower than 45% and 20% made up about 95% and 60% of the study area, respectively. Grazing significantly reduced monthly aboveground biomass, but the grazing effects on plant growth rate were complex across the different plant growth stages. Grazing impaired plant growth in general, but the intermediate GI appeared to facilitate plant growth rate at the end of the growing seasons. Grazing had minimal relationship with vegetation community structure characteristics, though Importance Value of forbs increased with increasing GI. Flexibility in the number of goats and conservatively defining utilization rate, according to the inter-annual variation of utilization biomass, would be beneficial to achieve ecologically healthy and economically sustainable GI.

How to manage the urban green to improve bird diversity and community structure

2011 ◽  
Vol 101 (3) ◽  
pp. 278-285 ◽  
Author(s):  
Simone Fontana ◽  
Thomas Sattler ◽  
Fabio Bontadina ◽  
Marco Moretti
Keyword(s):  
Community Structure ◽  
Bird Diversity ◽  
Urban Green

scholarly journals Dynamics of Bacterial Community Structure in the Rhizosphere and Root Nodule of Soybean: Impacts of Growth Stages and Varieties

2021 ◽  
Author(s):  
Soo-In Sohn ◽  
Jae-Hyung Ahn ◽  
Subramani Pandian ◽  
Young-Ju Oh ◽  
Eun-Kyoung Shin ◽  
...  
Keyword(s):  
Community Structure ◽  
Bacterial Community ◽  
Bacterial Community Structure ◽  
High Throughput Sequencing ◽  
Root Nodules ◽  
Growth Stages ◽  
Sequencing Analysis ◽  
Biolog Ecoplate ◽  
Metabolic Capability ◽  
Increasing Trend

Bacterial communities in rhizosphere and root nodules have significant contributions to the growth and productivity of the soybean (Glycine max L.). In this report, we analyzed the physiological properties and dynamics of bacterial community structure in rhizosphere and root nodules at different growth stages using BioLog EcoPlate and high-throughput sequencing technology, respectively. The BioLog assay found that the metabolic capability of rhizosphere is in increasing trend in the growth of soybeans as compared to the bulk soil. As a result of the Illumina sequencing analysis, the microbial community structure of rhizosphere and root nodules was found to be influenced by the variety and growth stage of the soybean. At the phylum level, Actinobacteria were the most abundant in rhizosphere at all growth stages, followed by Alphaproteobacteria and Acidobacteria and the phylum Bacteroidetes showed the greatest change. But, in the root nodules Alphaproteobacteria were dominant. The results of the OTU analysis exhibited the dominance of Bradyrhizobium during the entire stage of growth, but the ratio of non-rhizobial bacteria showed an increasing trend as the soybean growth progressed. These findings revealed that bacterial community in the rhizosphere and root nodules changed according to both the variety and growth stages of soybean in the field.

scholarly journals Root-associated microbiomes of wheat under the combined effect of plant development and nitrogen fertilization

Microbiome ◽  
2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Shuaimin Chen ◽  
Tatoba R. Waghmode ◽  
Ruibo Sun ◽  
Eiko E. Kuramae ◽  
Chunsheng Hu ◽  
...  
Keyword(s):  
Community Structure ◽  
Plant Growth ◽  
Microbial Communities ◽  
Root Zone ◽  
N Fertilization ◽  
Plant Roots ◽  
Growth Stages ◽  
Ripening Stages ◽  
N Input

Abstract Background Plant roots assemble microbial communities both inside the roots and in the rhizosphere, and these root-associated microbiomes play pivotal roles in plant nutrition and productivity. Although it is known that increased synthetic fertilizer input in Chinese farmlands over the past 50 years has resulted in not only increased yields but also environmental problems, we lack a comprehensive understanding of how crops under elevated nutrient input shape root-associated microbial communities, especially through adjusting the quantities and compositions of root metabolites and exudates. Methods The compositions of bacterial and fungal communities from the roots and rhizosphere of wheat (Triticum aestivum L.) under four levels of long-term inorganic nitrogen (N) fertilization were characterized at the tillering, jointing and ripening stages. The root-released organic carbon (ROC), organic acids in the root exudates and soil organic carbon (SOC) and soil active carbon (SAC) in the rhizosphere were quantified. Results ROC levels varied dramatically across wheat growth stages and correlated more with the bacterial community than with the fungal community. Rhizosphere SOC and SAC levels were elevated by long-term N fertilization but varied only slightly across growth stages. Variation in the microbial community structure across plant growth stages showed a decreasing trend with N fertilization level in the rhizosphere. In addition, more bacterial and fungal genera were significantly correlated in the jointing and ripening stages than in the tillering stage in the root samples. A number of bacterial genera that shifted in response to N fertilization, including Arthrobacter, Bacillus and Devosia, correlated significantly with acetic acid, oxalic acid, succinic acid and tartaric acid levels. Conclusions Our results indicate that both plant growth status and N input drive changes in the microbial community structure in the root zone of wheat. Plant growth stage demostrated a stronger influence on bacterial than on fungal community composition. A number of bacterial genera that have been described as plant growth-promoting rhizobacteria (PGPR) responded positively to N fertilization, and their abundance correlated significantly with the organic acid level, suggesting that the secretion of organic acids may be a strategy developed by plants to recruit beneficial microbes in the root zone to cope with high N input. These results provide novel insight into the associations among increased N input, altered carbon availability, and shifts in microbial communities in the plant roots and rhizosphere of intensive agricultural ecosystems.

Community structure of the microbiota associated with nodal roots of rice plants along with the growth stages: estimation by PCR-RFLP analysis

2002 ◽  
Vol 36 (6) ◽  
pp. 397-404 ◽  
Author(s):  
Makoto Ikenaga ◽  
Yoshitetsu Muraoka ◽  
Koki Toyota ◽  
Makoto Kimura
Keyword(s):  
Community Structure ◽  
Rflp Analysis ◽  
Growth Stages ◽  
Rice Plants ◽  
Nodal Roots ◽  
Pcr Rflp

scholarly journals Dynamics of Free-Living and Attached Bacterial Assemblages in Skeletonema sp. Diatom Cultures at Elevated Temperatures

2021 ◽  
Vol 8 ◽  
Author(s):  
Zichao Deng ◽  
Shouchang Chen ◽  
Ping Zhang ◽  
Xu Zhang ◽  
Jonathan M. Adams ◽  
...  
Keyword(s):  
Community Structure ◽  
Elevated Temperature ◽  
Bacterial Communities ◽  
Elevated Temperatures ◽  
Bacterial Species ◽  
Positive Interactions ◽  
Growth Stages ◽  
Free Living ◽  
Attached Bacteria ◽  
Living Bacteria

In the context of global warming, changes in phytoplankton-associated bacterial communities have the potential to change biogeochemical cycling and food webs in marine ecosystems. Skeletonema is a cosmopolitan diatom genus in coastal waters worldwide. Here, we grew a Skeletonema strain with its native bacterial assemblage at different temperatures and examined cell concentrations of Skeletonema sp. and free-living bacteria, dissolved organic carbon (DOC) concentrations of cultures, and the community structure of both free-living and attached bacteria at different culture stages. The results showed that elevated temperature increased the specific growth rates of both Skeletonema and free-living bacteria. Different growth stages had a more pronounced effect on community structure compared with temperatures and different physical states of bacteria. The effects of temperature on the structure of the free-living bacterial community were more pronounced compared with diatom-attached bacteria. Carbon metabolism genes and those for some specific amino acid pathways were found to be positively correlated with elevated temperature, which may have profound implications on the oceanic carbon cycle and the marine microbial loop. Network analysis revealed evidence of enhanced cooperation with an increase in positive interactions among different bacteria at elevated temperature. This may help the whole community to overcome the stress of elevated temperature. We speculate that different bacterial species may build more integrated networks with a modified functional profile of the whole community to cope with elevated temperature. This study contributes to an improved understanding of the response of diatom-associated bacterial communities to elevated temperature.

scholarly journals Big Bird Plots: Benchmarking Neotropical Bird Communities to Address Questions in Ecology and Conservation in an Era of Rapid Change

2021 ◽  
Vol 9 ◽  
Author(s):  
W. Douglas Robinson ◽  
Dan Errichetti ◽  
Henry S. Pollock ◽  
Ari Martinez ◽  
Philip C Stouffer ◽  
...  
Keyword(s):  
Community Structure ◽  
Community Dynamics ◽  
Rapid Change ◽  
Bird Species ◽  
Bird Communities ◽  
Lessons Learned ◽  
Bird Diversity ◽  
Future Research ◽  
Large Network ◽  
Bird Abundance

Extensive networks of large plots have the potential to transform knowledge of avian community dynamics through time and across geographical space. In the Neotropics, the global hotspot of avian diversity, only six 100-ha plots, all located in lowland forests of Amazonia, the Guianan shield and Panama, have been inventoried sufficiently. We review the most important lessons learned about Neotropical forest bird communities from those big bird plots and explore opportunities for creating a more extensive network of additional plots to address questions in ecology and conservation, following the model of the existing ForestGEO network of tree plots. Scholarly impact of the big bird plot papers has been extensive, with the papers accumulating nearly 1,500 citations, particularly on topics of tropical ecology, avian conservation, and community organization. Comparisons of results from the plot surveys show no single methodological scheme works effectively for surveying abundances of all bird species at all sites; multiple approaches have been utilized and must be employed in the future. On the existing plots, abundance patterns varied substantially between the South American plots and the Central American one, suggesting different community structuring mechanisms are at work and that additional sampling across geographic space is needed. Total bird abundance in Panama, dominated by small insectivores, was double that of Amazonia and the Guianan plateau, which were dominated by large granivores and frugivores. The most common species in Panama were three times more abundant than those in Amazonia, whereas overall richness was 1.5 times greater in Amazonia. Despite these differences in community structure, other basic information, including uncertainty in population density estimates, has yet to be quantified. Results from existing plots may inform drivers of differences in community structure and create baselines for detection of long-term regional changes in bird abundances, but supplementation of the small number of plots is needed to increase generalizability of results and reveal the texture of geographic variation. We propose fruitful avenues of future research based on our current synthesis of the big bird plots. Collaborating with the large network of ForestGEO tree plots could be one approach to improve understanding of linkages between plant and bird diversity. Careful quantification of bird survey effort, recording of exact locations of survey routes or stations, and archiving detailed metadata will greatly enhance the value of benchmark data for future repeat surveys of the existing plots and initial surveys of newly established plots.

scholarly journals Yak rumen microbial diversity at different forage growth stages of an alpine meadow on the Qinghai-Tibet Plateau

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7645 ◽  
Author(s):  
Li Ma ◽  
Shixiao Xu ◽  
Hongjin Liu ◽  
Tianwei Xu ◽  
Linyong Hu ◽  
...  
Keyword(s):  
Community Structure ◽  
Bacterial Community ◽  
Microbial Diversity ◽  
Alpine Meadow ◽  
Nutrient Composition ◽  
Tibet Plateau ◽  
Growth Stages ◽  
Rumen Microbiota ◽  
Three Stages ◽  
Qinghai Tibet Plateau

The rumen microbiota of ruminants plays a vital role in fiber digestion, and environmental factors affect its community structure. The yak (Bos grunniens) is the main livestock species that inhabits the Qinghai-Tibet Plateau (QTP) at regions located at high-altitude of 3,000–5,000 m. This work investigated the rumen bacterial community of yak that grazed on the QTP during the whole year to evaluate the relationship between the rumen bacterial community and the nutrient composition of forage plant at three stages. In this study, the diversity of the rumen prokaryotic community composition was monitored in 10 full-grazing yak in an alpine meadow of the QTP. The nutrient composition of three forage growth stages was determined: re-green stage (REGY), grassy stage (GY), and withered stage (WGY). High-throughput sequencing of bacterial 16S rRNA gene was used. The results showed that the nutritive composition of the alpine meadow changed with the seasons: crude protein (CP) (13.22%) was high in forage during REGY (spring), while neutral detergent fiber (NDF) (59.00%) was high during WGY (winter). Microbial diversity and richness were highest during REGY and the average number of operational taxonomic units from 30 samples was 4,470. The microbial composition was dominated by members of Bacteroidetes (51.82%), followed by Firmicutes (34.08%), and the relative microbial abundance changed in the three forage growth stages. Unweighted UniFrac distance PcoA showed that the bacterial community structure differed between REGY, GY, and WGY. Furthermore, taxonomic groups did not present differences regarding gender in these three stages. The rumen microbiota was enriched with functional potentials that were related to ABC transporters, the two-component system, Aminoacyl-tRNA biosynthesis, and metabolism of Purine, Pyrimidine, Starch and sucrose metabolism. Significant differences were found in the composition, diversity, and function of yak ruminal microorganisms during different forage growth stages. This indicates that microbial changes in the rumen depend on changes in the forage nutritional composition. These findings provide evidence on the rumen microbial diversity of yaks in the QTP.

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