scholarly journals The rise of grasslands is linked to atmospheric CO2 decline in the late Palaeogene

2021 ◽  
Author(s):  
Luis Palazzesi ◽  
Oriane Hidalgo ◽  
Viviana D Barreda ◽  
Felix Forest ◽  
Sebastian Hoehna
Keyword(s):  
Bayesian Approach ◽  
Strong Evidence ◽  
Environmental Variables ◽  
Statistical Approach ◽  
Environmental Changes ◽  
Temperature Fluctuations ◽  
Simultaneous Increase ◽  
Diversification Rates ◽  
Biodiversity Change ◽  
The Relationship

Grasslands are predicted to experience a major biodiversity change by the year 2100 in part due to recent and projected increases in atmospheric CO2 concentration. A better understanding of how grasslands have responded to past environmental changes will help predict the outcome of current and future environmental changes. Here, we explore the relationship between past atmospheric CO2 and temperature fluctuations and the shifts in diversification rate of grasses (Poaceae) and daisies (Asteraceae), two exceptionally species-rich grassland families (≈ 11,000 and ≈ 23,000 species, respectively). To this end, we developed a novel Bayesian approach that simultaneously estimates diversification-rates through time from time-calibrated phylogenies and correlations between environmental variables and diversification rates. Additionally, we developed a new statistical approach that incorporates the information of the distribution of missing species in the phylogeny. We found strong evidence supporting a simultaneous increase in diversification rates for daisies and grasses after the most significant reduction of atmospheric CO2 in the Cenozoic (≈ 34 Mya). The fluctuations of paleo-temperatures, however, appear not to have had a significant relationship with the diversification of these grassland families. Overall, our results shed new light on our understanding of the origin of grasslands in the context of past environmental changes.

scholarly journals The rise of grasslands is linked to atmospheric CO2 decline in the late Palaeogene

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Luis Palazzesi ◽  
Oriane Hidalgo ◽  
Viviana D. Barreda ◽  
Félix Forest ◽  
Sebastian Höhna
Keyword(s):  
Bayesian Approach ◽  
Strong Evidence ◽  
Environmental Variables ◽  
Statistical Approach ◽  
Environmental Changes ◽  
Temperature Fluctuations ◽  
Simultaneous Increase ◽  
Diversification Rates ◽  
Biodiversity Change ◽  
The Relationship

AbstractGrasslands are predicted to experience a major biodiversity change by the year 2100. A better understanding of how grasslands have responded to past environmental changes will help predict the outcome of current and future environmental changes. Here, we explore the relationship between past atmospheric CO2 and temperature fluctuations and the shifts in diversification rate of Poaceae (grasses) and Asteraceae (daisies), two exceptionally species-rich grassland families (~11,000 and ~23,000 species, respectively). To this end, we develop a Bayesian approach that simultaneously estimates diversification rates through time from time-calibrated phylogenies and correlations between environmental variables and diversification rates. Additionally, we present a statistical approach that incorporates the information of the distribution of missing species in the phylogeny. We find strong evidence supporting a simultaneous increase in diversification rates for grasses and daisies after the most significant reduction of atmospheric CO2 in the Cenozoic (~34 Mya). The fluctuations of paleo-temperatures, however, appear not to have had a significant relationship with the diversification of these grassland families. Overall, our results shed new light on our understanding of the origin of grasslands in the context of past environmental changes.

scholarly journals Monitoring studies should consider temporal variability to reveal relations between cyanobacterial abundance and environmental variables

2015 ◽  
Vol 87 (3) ◽  
pp. 1717-1726 ◽  
Author(s):  
JULIANA WOJCIECHOWSKI ◽  
ANDRÉ A. PADIAL
Keyword(s):  
Temporal Variability ◽  
Environmental Variables ◽  
Environmental Changes ◽  
Environmental Variability ◽  
Time Lag ◽  
Cyanobacteria Blooms ◽  
Environment Variables ◽  
Sampling Points ◽  
The Relationship

One of the main goals of monitoring cyanobacteria blooms in aquatic environments is to reveal the relationship between cyanobacterial abundance and environmental variables. Studies typically correlate data that were simultaneously sampled. However, samplings occur sparsely over time and may not reveal the short-term responses of cyanobacterial abundance to environmental changes. In this study, we tested the hypothesis that stronger cyanobacteria x environment relationships in monitoring are found when the temporal variability of sampling points is incorporated in the statistical analyses. To this end, we investigated relationships between cyanobacteria and seven environmental variables that were sampled twice yearly for three years across 11 reservoirs, and data from an intensive monitoring in one of these reservoirs. Poor correlations were obtained when correlating data simultaneously sampled. In fact, the 'highly recurrent' role of phosphorus in cyanobacteria blooms is not properly observed in all sampling periods. On the other hand, the strongest correlation values for the total phosphorus x cyanobacteria relationship were observed when we used the variation of sampling points. We have also shown that environment variables better explain cyanobacteria when a time lag is considered. We conclude that, in cyanobacteria monitoring, the best approach to reveal determinants of cyanobacteria blooms is to consider environmental variability.

Self-Regulating Crop Selector for Improved Production Using Big Data

2020 ◽  
Vol 17 (8) ◽  
pp. 3657-3659
Author(s):  
K. Mohana Prasad ◽  
M. Surya Prakash
Keyword(s):  
Climate Change ◽  
Cluster Analysis ◽  
Big Data ◽  
Environmental Variables ◽  
Human Population ◽  
Environmental Changes ◽  
Data Normalization ◽  
Agricultural Produce ◽  
Smart Agriculture ◽  
The Relationship

The ever-increasing market for agricultural produce comes and the human population rising. But, when the planet is undergoing climate change, environmental changes also threaten many crops. This research uses Smart Agriculture IoT to track environmental conditions at a farm. The data obtained were analyzed in 3D clusters to provide an environmental overview. The suggested system has the following characteristics: 1. data normalization is accomplished by integrating average and median variance shifts 2. 3D cluster analysis was applied to assess the relationship between environmental variables and then investigate the thumb rules kept by farmers; 3. the method decides whether a chosen crop was put in the correct cluster; and 4. We placed IoT equipment for Intelligent Agriculture in the field for supervising functions and carried out an actual scenario review.

scholarly journals Impact of Foehn Wind and Related Environmental Variables on the Incidence of Cardiac Events

2020 ◽  
Vol 17 (8) ◽  
pp. 2638 ◽  
Author(s):  
Andrzej Maciejczak ◽  
Agnieszka Guzik ◽  
Andżelina Wolan-Nieroda ◽  
Marzena Wójcik ◽  
Teresa Pop
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Environmental Variables ◽  
Environmental Changes ◽  
Regional Hospital ◽  
Study Group ◽  
Cardiac Events ◽  
Weather Phenomenon ◽  
The Impact ◽  
The Relationship

In Poland there is no data related to the impact of halny wind and the related environmental variables on the incidence of cardiac events. We decided to investigate the relationship between this weather phenomenon, as well as the related environmental variables, and the incidence of cardiac events in the population of southern Poland, a region affected by this type of wind. We also decided to determine whether the environmental changes coincide with or predate the event examined. We analysed data related to 465 patients admitted to the cardiology ward in a large regional hospital during twelve months of 2011 due to acute myocardial infarction. All the patients in the study group lived in areas affected by halny wind and at the time of the event were staying in those areas. The frequency of admissions on halny days did not differ significantly from the admissions on the remaining days of the year (p = 0.496). No statistically significant differences were found between the number of admissions on halny days and on the remaining days during halny months (p = 0.084). We have identified a difference in the number of admissions between days with no halny and days immediately preceding onset of halny (p = 0.001). However, no effects of the related environmental variables have been observed in the incidence of cardiac events (p = 0.866, F = 0.37). On the days with halny wind, incidence of cardiac events is similar to that on the remaining days of the year.

Konsep Asbāb Al-Nuzūl Menurut Nashr Hamid Abu Zayd

2018 ◽  
Vol 3 (1) ◽  
pp. 104-118
Author(s):  
Shidqy Munjin
Keyword(s):  
Strong Evidence ◽  
The Relationship

This article aims to examine the concept of asbāb al-nuzul which has been misunderstood by ulama and thus produces misleading conclusions. The results of this study indicate that Abu Zayd's criticism of the established concept of asbāb al-nuzūl in the ‘ulūm Al-Qurān was focused on the problem of the relation between the text and realities. According to him, the study of the first scholars was too focused on the Koran itself and the Prophet's person as the recipient of revelation, but they forgot the community around the Prophet which was the most important element of reality that existed at that time. Whereas for Abu Zayd, the existence of asbāb al-nuzūl is strong evidence to show the relationship and dialectic between text and reality. To elaborate on his conception, Abu Zayd elaborated on four basic problems, namely regarding the reasons for the Al-Qur'an's a gradual descent, the gradual model of decline, the concept of Dalāllah in understanding a verse and its relation to asbāb al-nuzūl and finally on how to determine asbāb al-nuzūl.

scholarly journals Collection of Environmental Variables and Bacterial Community Compositions in Marian Cove, Antarctica, during Summer 2018

Data ◽  
2021 ◽  
Vol 6 (3) ◽  
pp. 27
Author(s):  
Hyo-Ryeon Kim ◽  
Jae-Hyun Lim ◽  
Ju-Hyoung Kim ◽  
Il-Nam Kim
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
Marine Bacteria ◽  
Environmental Variables ◽  
Environmental Changes ◽  
Bacterial Community Composition ◽  
Composition Data ◽  
Decomposition Of Organic Matter ◽  
Class Level ◽  
Earth’S Climate

Marine bacteria, which are known as key drivers for marine biogeochemical cycles and Earth’s climate system, are mainly responsible for the decomposition of organic matter and production of climate-relevant gases (i.e., CO₂, N₂O, and CH₄). However, research is still required to fully understand the correlation between environmental variables and bacteria community composition. Marine bacteria living in the Marian Cove, where the inflow of freshwater has been rapidly increasing due to substantial glacial retreat, must be undergoing significant environmental changes. During the summer of 2018, we conducted a hydrographic survey to collect environmental variables and bacterial community composition data at three different layers (i.e., the seawater surface, middle, and bottom layers) from 15 stations. Of all the bacterial data, 17 different phylum level bacteria and 21 different class level bacteria were found and Proteobacteria occupy 50.3% at phylum level following Bacteroidetes. Gammaproteobacteria and Alphaproteobacteria, which belong to Proteobacteria, are the highest proportion at the class level. Gammaproteobacteria showed the highest relative abundance in all three seawater layers. The collection of environmental variables and bacterial composition data contributes to improving our understanding of the significant relationships between marine Antarctic regions and marine bacteria that lives in the Antarctic.

Past testate amoeba communities in landslide mountain fens (Polish Carpathians): The relationship between shell types and sediment

The Holocene ◽  
2021 ◽  
pp. 095968362199464
Author(s):  
Katarzyna Marcisz ◽  
Krzysztof Buczek ◽  
Mariusz Gałka ◽  
Włodzimierz Margielewski ◽  
Matthieu Mulot ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Testate Amoebae ◽  
Mineral Matter ◽  
Testate Amoeba ◽  
Run Off ◽  
Number Of Factors ◽  
Depth To Water Table ◽  
Polish Carpathians ◽  
The Relationship

Landslide mountain fens formed in landslide depressions are dynamic environments as their development is disturbed by a number of factors, for example, landslides, slopewash, and surface run-off. These processes lead to the accumulation of mineral material and wood in peat. Disturbed peatlands are interesting archives of past environmental changes, but they may be challenging for providing biotic proxy-based quantitative reconstructions. Here we investigate long-term changes in testate amoeba communities from two landslide mountain fens – so far an overlooked habitat for testate amoeba investigations. Our results show that abundances of testate amoebae are extremely low in this type of peatlands, therefore not suitable for providing quantitative depth-to-water table reconstructions. However, frequent shifts of dominant testate amoeba species reflect dynamic lithological situation of the studied fens. We observed that high and stable mineral matter input into the peatlands was associated with high abundances of species producing agglutinated (xenosomic) as well as idiosomic shells which prevailed in the testate amoeba communities in both analyzed profiles. This is the first study that explores testate amoebae of landslide mountain fens in such detail, providing novel information about microbial communities of these ecosystems.

scholarly journals Forecasting Agroforestry Ecosystem Services Provision in Urban Regeneration Projects: Experiences and Perspectives from Milan

2021 ◽  
Vol 13 (5) ◽  
pp. 2434 ◽  
Author(s):  
Ambrogio Zanzi ◽  
Federico Andreotti ◽  
Valentina Vaglia ◽  
Sumer Alali ◽  
Francesca Orlando ◽  
...  
Keyword(s):  
Ecosystem Services ◽  
Food System ◽  
Environmental Changes ◽  
Urban Environments ◽  
Urban Food System ◽  
Notable Increase ◽  
Living Fences ◽  
The Difference ◽  
Pollution Removal ◽  
The Relationship

The expansion of urban agglomerates is causing significant environmental changes, while the demand and need for sustainability keep on growing. In this context, urban and peri-urban agriculture can play a crucial role, mainly if associated with an agroecological approach. Indeed, the extensive use of living fences and tree rows can improve the environmental quality, assuring ecosystem services (ES), developing a sustainable urban food system and increasing local productions and the related socio-economic improvements. This study aims to assess the benefits of an agroecological requalification of a dismissed peri-urban area in the South Milan Agricultural Regional Park (Italy), by evaluating two possible scenarios, both involving planting trees and shrubs in that area. The software I-Tree Eco simulates the ecosystem services provision of planting new hedgerows, evaluating the benefits over 30 years. The study underlines the difference between the two scenarios and how the planted area becomes an essential supplier of regulating ecosystem services for the neighbourhoods, increasing carbon storage and air pollution removal. Results were then analysed with a treemap, to better investigate and understand the relationship between the different ecosystem services, showing a notable increase in carbon sequestration at the end of the simulation (at year 30). The study shows a replicable example of a methodology and techniques that can be used to assess the ES in urban and peri-urban environments.

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