Climate Change and Ocean Acidification: Are We Just Treating The Symptoms?

The human caused rise in atmospheric greenhouse gases has been seen as the driver of both climate change and ocean acidification. However recent peer reviewed papers show that, while GHG emissions are part of the problem, the primary driver of both climate change and ocean acidification is human caused ecological degradation. Curbing greenhouse gas emissions, to date, has been an abject failure but addressing ecological degradation within the remaining time frame is safe and achievable.

What Seismic Minimum Reveals about Solar Magnetism below the Surface

The Sun’s magnetic field varies on multiple timescales. Observations show that the minimum between cycles 24 and 25 was the second consecutive minimum that was deeper and wider than several earlier minima. Since the active regions observed at the Sun’s surface are manifestations of the magnetic field generated in the interior, it is crucial to investigate/understand the dynamics below the surface. In this context, we report by probing the solar interior with helioseismic techniques applied to long-term oscillations data from the Global Oscillation Network Group, that the seismic minima in deeper layers have been occurring about a year earlier than that at the surface for the last two consecutive solar cycles. Our findings also demonstrate a decrease in strong magnetic fields at the base of the convection zone, the primary driver of the surface magnetic activity. We conclude that the magnetic fields located in the core and near-surface shear layers, in addition to the tachocline fields, play an important role in modifying the oscillation frequencies. This further strengthens the existence of a relic magnetic field in the Sun’s core.

An evapotranspiration deficit-based drought index to detect variability of terrestrial carbon productivity in the Middle East

The primary driver of the land carbon sink is gross primary productivity (GPP), the gross absorption of carbon dioxide (CO2) by plant photosynthesis, which currently accounts for about one-quarter of anthropogenic CO2 emissions per year. This study aimed to detect the variability of carbon productivity using the Standardized Evapotranspiration Deficit Index (SEDI). Sixteen countries in the Middle East (ME) were selected to investigate drought. To this end, the yearly GPP dataset for the study area, spanning the 35 years (1982–2017) was used. Additionally, the Global Land Evaporation Amsterdam Model (GLEAM, version 3.3a), which estimates the various components of terrestrial evapotranspiration (annual actual and potential evaporation), was used for the same period. The main findings indicated that productivity in croplands and grasslands was more sensitive to the SEDI in Syria, Iraq, and Turkey by 34, 30.5, and 29.6% of cropland area respectively, and 25 31.5 and 30.5% of grass land area. A significant positive correlation against the long-term data of the SEDI was recorded. Notably, the GPP recorded a decline of >60% during the 2008 extreme drought in the north of Iraq and the northeast of Syria, which concentrated within the agrarian ecosystem and reached a total vegetation deficit with 100% negative anomalies. The reductions of the annual GPP and anomalies from 2009 to 2012 might have resulted from the decrease in the annual SEDI at the peak 2008 extreme drought event. Ultimately, this led to a long delay in restoring the ecosystem in terms of its vegetation cover. Thus, the proposed study reported that the SEDI is more capable of capturing the GPP variability and closely linked to drought than commonly used indices. Therefore, understanding the response of ecosystem productivity to drought can facilitate the simulation of ecosystem changes under climate change projections.

Series Arc Fault Breaker in Low Voltage Using Microcontroller Based on Fast Fourier Transform

Series Arc Fault is one of the disturbances of arcing jump is caused by gas ionization between two ends of damaged conductors or broken wire forming a gap in the insulator. Series arc fault is the primary driver of electrical fire. However, lack of knowledge of the disturbance of series arc fault causes the problem of electrical fire not be mitigated. Magnitude current is not capable to detect of series arc fault. Therefore, this paper proposes fast fourier transform (FFT) to detect series AC arc fault in low voltage using microcontroller ARM STM32F7NGH in real time. A cheap and high speed of microcontroller ARM STM32F7NGH can be used for FFT computation to transform signal in time domain to frequency domain. Moreover, in this paper, protection of series AC arc fault is proposed in the real time mode. In this experimental process, some various experiments are tested to evaluate the reliability of FFT and protection with various load starts from 1 A, 2 A, 3 A, 4 A in resistive load. The result of this experiment shows that series AC arc fault protection with STM32F7 microcontroller and FFT algorithm can be utilized to ensure series AC arc fault properly.

The neural bases of vertebrate motor behaviour through the lens of evolution

The primary driver of the evolution of the vertebrate nervous system has been the necessity to move, along with the requirement of controlling the plethora of motor behavioural repertoires seen among the vast and diverse vertebrate species. Understanding the neural basis of motor control through the perspective of evolution, mandates thorough examinations of the nervous systems of species in critical phylogenetic positions. We present here, a broad review of studies on the neural motor infrastructure of the lamprey, a basal and ancient vertebrate, which enjoys a unique phylogenetic position as being an extant representative of the earliest group of vertebrates. From the central pattern generators in the spinal cord to the microcircuits of the pallial cortex, work on the lamprey brain over the years, has provided detailed insights into the basic organization (a bauplan ) of the ancestral vertebrate brain, and narrates a compelling account of common ancestry of fundamental aspects of the neural bases for motion control, maintained through half a billion years of vertebrate evolution. This article is part of the theme issue ‘Systems neuroscience through the lens of evolutionary theory’.

Macrogenetics reveals multifaceted influences of environmental variation on vertebrate population genetic diversity across the Americas

Relative to species diversity gradients, the broad scale distribution of population-specific genetic diversity (PGD) across taxa remains understudied. We used nuclear DNA data collected from 6285 vertebrate populations across the Americas to assess the role environmental variables play in structuring the spatial/latitudinal distribution of PGD, a key component of adaptive potential in the face of environmental change. Our results provide key evidence for taxa-specific responses and that temperature variability in addition to mean temperature may be a primary driver of PGD. Additionally, we found some positive influence of precipitation, productivity, and elevation on PGD; identified trends were dependent on the metric of PGD. In contrast to the classic negative relationship between species diversity and latitude, we report either a positive or taxa-dependent relationship between PGD and latitude, depending on the metric of PGD. The inconsistent latitudinal gradient in different metrics of PGD may be due to opposing processes diminishing patterns across latitudes that operate on different timescales, as well as the flattening of large-scale genetic gradients when assessing across species versus within species. Our study highlights the nuance required to assess broad patterns in genetic diversity, and the need for developing balanced conservation strategies that ensure population, species, and community persistence.

Autotoxin Rg 1 Induces Degradation of Root Cell Walls and Aggravates Root Rot by Modifying the Rhizospheric Microbiome

The accumulation of autotoxins and pathogens in soil has been reported as a primary driver of root rot disease and one of the key factors limiting sustainable development in agricultural production. However, less is known about the correlation of plants, their associated pathogens, and the microbiota mediated by autotoxins, as well as the contributions autotoxins make to the occurrence of root rot disease.

Agriculture is the primary driver of tree cover loss across the Forestière region of the Republic of Guinea, Africa

Biodiversity hotspots are conservation priority areas that feature exceptionally high levels of species endemism and high levels of habitat loss. The Guinean Forests of West Africa hotspot, home to a quarter of all the mammal species of Africa, has experienced high levels of forest loss within its protected areas. Here, we analyzed tree cover loss and its proximate drivers within Guinée Forestière, a high biodiversity region within the Guinean Forests of West Africa hotspot, both inside and outside protected areas. Using Landsat analysis ready data and a regionally calibrated, annual forest change detection model, we mapped tree cover loss occurring across this region from 2000 to 2018. We quantified the area of tree cover loss and identified proximate drivers using a statistical sample of reference data. The total tree cover loss in Guinée Forestière between years 2000 and 2018 was 10,907 km2 (SE 889 km2), which consists of approximately 25% of the region’s total land area. Of this total loss, 364 km2 (SE 91 km2) occurred within protected areas of high biodiversity value. Tree cover loss was not consistent across high biodiversity areas and did not appear to be related to protected area classification. Smallholder agriculture (subsistence and cash crop farming) was the primary driver of tree cover loss across Guinée Forestière. This research provides multitemporal spatial data on tree cover dynamics that is required for effective implementation of sustainable management and biodiversity conservation strategies within the broader socioecological landscape of Guinée Forestière. We also highlight important limitations to consider and address when using remote sensing to automate change detection across landscapes.

System leadership in Australian and Swedish education: What’s social justice got to do with it?

Since the start of the 21st century, education in Australia and Sweden have seen system level reform efforts change and shape both nations’ schools. In an endeavour to improve the educational outcomes of students, both countries have enacted neoliberal policies that aimed to decentralise education and provide increased autonomy for school leaders. The real-world consequences of these policies have restricted school leader autonomy and academic performance has declined while the gap between advantaged and disadvantaged students has continually grown. When excellence trumps equity as the primary driver of education at the system level, it creates a disadvantage cycle which sees the development of societal status hierarchies and unjust participatory parity for particular social groups. In the current time of COVID-19, when these disadvantages are exacerbated, it is timely to evaluate educational leadership at the system level in terms of its ability to positively affect social justice issues. Social justice leadership at a system level holds the potential to unite schools in competition and empower them to help overcome the unjust reality faced by disadvantaged students. So, the focus of this piece is to provide commentary on whether system leadership can enhance education’s potential in realising a more socially just society.