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Biodiversity patterns are shaped by the interplay between geodiversity and organismal characteristics. Superimposing genetic structure onto landscape heterogeneity (i.e., landscape genetics) can help to disentangle their interactions and better understand population dynamics. Previous studies on the sub‐Antarctic Prince Edward Islands (located midway between Antarctica and Africa) have highlighted the importance of landscape and climatic barriers in shaping spatial genetic patterns and have drawn attention to the value of these islands as natural laboratories for studying fundamental concepts in biology. Here, we assessed the fine‐scale spatial genetic structure of the springtail, Cryptopygus antarcticus travei, which is endemic to Marion Island, in tandem with high‐resolution geological data. Using a species‐specific suite of microsatellite markers, a fine‐scale sampling design incorporating landscape complexity and generalised linear models (GLMs), we examined genetic patterns overlaid onto high‐resolution digital surface models and surface geology data across two 1‐km sampling transects. The GLMs revealed that genetic patterns across the landscape closely track landscape resistance data in concert with landscape discontinuities and barriers to gene flow identified at a scale of a few metres. These results show that the island's geodiversity plays an important role in shaping biodiversity patterns and intraspecific genetic diversity. This study illustrates that fine‐scale genetic patterns in soil arthropods are markedly more structured than anticipated, given that previous studies have reported high levels of genetic diversity and evidence of genetic structing linked to landscape changes for springtail species and considering the homogeneity of the vegetation complexes characteristic of the island at the scale of tens to hundreds of metres. By incorporating fine‐scale and high‐resolution landscape features into our study, we were able to explain much of the observed spatial genetic patterns. Our study highlights geodiversity as a driver of spatial complexity. More widely, it holds important implications for the conservation and management of the sub‐Antarctic islands. [ABSTRACT FROM AUTHOR]

This research explores intra-gully sediment volume changes of a massive gully network (42 ha) located in the Eastern Cape, RSA, in response to high rainfall events during a three-year study period (2017–2020). Unmanned aerial vehicles (UAVs) and photogrammetric processing were used to generate high resolution digital surface models (DSMs). Volumetric calculations were run to estimate the extent of gully expansion within the system to determine intra-gully changes and sediment erosion over the study period. The gully was categorised into four zones based on predominant structure and processes. These are the Extension Zone, Expansion Zone, Transport/Deposition Zone and the Side Branches. Rainfall data from a rainfall station (10 km away) was used to investigate the correlation between rainfall depth, rainfall intensity, and flow accumulation over two wetter years and one drier year with gully expansion experienced during these periods. The gully network encountered a total gully sediment volume erosion of 104,489 m3 (6.01%) over the study period. Nineteen high to extreme intensity (>20 mm per day) rainfall events produced the runoff necessary for gully expansion during the 2017 and 2018 hydrological years. Notably, lower gully growth was recorded in the Expansion and Transport/Deposition Zones during the subsequent below average hydrological year in 2019–2020. [ABSTRACT FROM AUTHOR]

Biodiversity patterns are shaped by the interplay between geodiversity and organismal characteristics. Superimposing genetic structure onto landscape heterogeneity (i.e., landscape genetics) can help to disentangle their interactions and better understand population dynamics. Previous studies on the sub‐Antarctic Prince Edward Islands (located midway between Antarctica and Africa) have highlighted the importance of landscape and climatic barriers in shaping spatial genetic patterns and have drawn attention to the value of these islands as natural laboratories for studying fundamental concepts in biology. Here, we assessed the fine‐scale spatial genetic structure of the springtail, Cryptopygus antarcticus travei, which is endemic to Marion Island, in tandem with high‐resolution geological data. Using a species‐specific suite of microsatellite markers, a fine‐scale sampling design incorporating landscape complexity and generalised linear models (GLMs), we examined genetic patterns overlaid onto high‐resolution digital surface models and surface geology data across two 1‐km sampling transects. The GLMs revealed that genetic patterns across the landscape closely track landscape resistance data in concert with landscape discontinuities and barriers to gene flow identified at a scale of a few metres. These results show that the island's geodiversity plays an important role in shaping biodiversity patterns and intraspecific genetic diversity. This study illustrates that fine‐scale genetic patterns in soil arthropods are markedly more structured than anticipated, given that previous studies have reported high levels of genetic diversity and evidence of genetic structing linked to landscape changes for springtail species and considering the homogeneity of the vegetation complexes characteristic of the island at the scale of tens to hundreds of metres. By incorporating fine‐scale and high‐resolution landscape features into our study, we were able to explain much of the observed spatial genetic patterns. Our study highlights geodiversity as a driver of spatial complexity. More widely, it holds important implications for the conservation and management of the sub‐Antarctic islands. [ABSTRACT FROM AUTHOR]

Asian dust delivers highly reactive iron (FeHR) to the Pacific Ocean, affecting marine biogeochemical cycles and Earth's climate. Tracing the source of dust deposited in the Pacific is vital for assessing global nutrient cycles but poses challenges. This work applies the (234U/238U) activity ratio to determine the pre‐deposition time and provenance of dust in North Pacific Ocean sediments (Ocean Drilling Program site 1209B). Results indicate a consistent dust pre‐deposition time (134 ± 10 ka) over the past 300,000 years, except during Marine Isotope Stage 7 when volcanic ash input shortened it to 31 ± 19 ka. Comparing the dust pre‐deposition times to those of the potential source deserts, we identify the dust transported to the North Pacific Ocean was primarily from the Taklamakan Desert, which contains higher FeHR content than other deserts. This finding enhances our understanding of soluble Fe supplied to the oceans, especially in dust circulation models. Plain Language Summary: Unraveling the provenance of aeolian dust deposited in the oceans is critical for understanding marine biogeochemical cycles, past climate changes, and dust transport mechanisms. Here we measured the (234U/238U) activity ratio of marine sediments in the North Pacific Ocean to understand the source and pre‐deposition time of dust deposited in the Pacific. The source of dust in the Pacific has remained debated because of the non‐unique geochemical signatures of possible source regions and the complexity introduced by the volcanic ash. The (234U/238U) of the dust fraction in marine sediments informs the source‐to‐sink transport time for dust particles, providing a new source tracer. We compared the (234U/238U)‐derived pre‐deposition time, Nd isotopes, grain size, magnetic susceptibility and aeolian dust flux of the North Pacific marine sediments to those of potential dust source regions, and identify the Taklamakan Desert as a major source delivering dust to the North Pacific. Our work highlights the (234U/238U) and associated particle pre‐deposition time as a promising tool for tracing sources of dust in marine sediments, holding profound implications for our understanding of global dust‐nutrient cycles. Key Points: Uranium isotope‐based pre‐deposition time serves as a novel tool to trace the provenance of Asian dust transported to the North Pacific OceanDust pre‐deposition time at site 1209B remains relativity stable (134 ± 10 ka), but decreases during MIS 7 due to volcanic ash inputTaklimakan Desert is the major source of dust delivered to the North Pacific Ocean, supplying dust with highly reactive iron [ABSTRACT FROM AUTHOR]

The aeolian loess deposits in northeastern China have substantial potential for reconstructing the paleoclimate in the East Asian monsoon boundary zone. Identifying the source of the aeolian dust is crucial to interpret the paleo‐proxies recorded in the loess deposits in northeastern China; however, traditional geochemical tracers such as Nd and Sr isotopes cannot discriminate between the potential source areas, that is, the Otindag Sandy Land, Horqin Sandy Land, and Hulun Buir Sandy Land regions. In this study, the (234U/238U) activity ratio is used to constrain the provenance of the loess deposits in northeastern China. The (234U/238U) of the studied loess‐paleosol sequences (from 0.935 to 0.910) decreases with increasing depositional age (from 10 to ∼1,000 ka), which is consistent with predictions from uranium isotope comminution age model. A derived (234U/238U) of 0.935 ± 0.003 for the newly deposited loess (zero depositional age) is most similar to that of the Otindag Sandy Land positioned at a proximal upwind direction, suggesting that the Otindag Sandy Land is the most likely source of the aeolian dust that formed the loess deposits in northeastern China. A transportation time of 432 ± 65 ka was calculated for these deposits, indicating extensive mixing of the fine dust in the source regions, which could partially explain the relative homogeneity of loess deposits in northeastern China. The transportation time longer than several glacial‐interglacial cycles suggests that reconstructions of regional paleoclimate on orbital timescales should be viewed with caution because the potential influence of climatic changes could largely be buffered. Plain Language Summary: The activity ratio of the uranium isotopes (234U and 238U) in fine‐grained particles can be used to determine the "comminution age", or the amount of time since the production of fine sediment particles (≤50 μm) from the breakdown of bedrock by weathering. The (234U/238U) activity ratio provides a new approach to track the age and origin of dust particles. In this study, we measure the (234U/238U) composition of the loess deposits in northeastern China and surface sand samples in potential source areas to better understand the transport of aeolian dust in the region. We find that the Otindag Sandy Land, which is in the proximal upwind direction, is the main source region for the loess deposits in northeastern China and that the dust materials have been resided in the source region for around 432 ± 65 thousand years before aeolian transport and deposition. Our results shed light on the transport and depositional history of loess in northeastern China and provide valuable information for reconstructing paleoclimate using the loess deposits in this region. Key Points: The (234U/238U) activity ratio of a loess sequence in northeastern China is consistent with a uranium isotope comminution age modelLoess deposits found in northeastern China have a long residence time of 432 ± 65 ka in the source regionsThe Otindag Sandy Land in the proximal upwind direction is the main source region for the studied loess sequence [ABSTRACT FROM AUTHOR]

Gully erosion can reach alarming dimensions, and in several cases contributes significantly to soil loss and sediment yield in catchments. The studied example is one of the largest known gully networks in the world (its surface area is approximately 0.5 million m2 and volume 5 million m3), more than twice as large compared to the largest gullies described in peer-reviewed literature. To improve gully management strategies, it is not only critical to understand the factors that lead to erosion, but also to identify the extent of in-channel erosional and depositional features. Few studies consider in-channel patterns of erosion and deposition within gully systems. This study utilises a fixed-wing Unmanned Aerial Vehicle (UAV) and Structure-from-Motion (SfM) photogrammetry to create a high resolution orthomosaic and Digital Surface Model (DSM) to determine the position and spatial extent of erosional and depositional features within a large gully network in South Africa. Formation of such a large gully in relation to a relatively small drainage area is unusual but can be explained by the presence of dispersive soils and regional landscape incision. Longitudinal and cross-sectional profiles indicate that the gully network consists of three channel types (i.e. V-shaped, U-shaped and trapezoidal), each with a unique combination of erosional and depositional features. This study demonstrates the value of identifying and mapping of intra-gully features to better understand sediment transfer within the gully network to implement appropriate restoration strategies, which in this instance should focus on depositional zones to enhance channel decoupling. [ABSTRACT FROM AUTHOR]

Projecting future changes in effective precipitation under global warming, which requires constraints on both the precipitation and evapotranspiration, is still challenging in the semi‐arid region of East Asia. Here we present proxies, based on Sr/Ca and 87Sr/86Sr of soil carbonate, to reconstruct the evolution of both effective precipitation and temperature from a high‐resolution loess profile in the East Asian monsoon marginal area covering the last interglacial period as a geological analog for future conditions. We find that intervals with a stronger summer monsoon are characterized by lower effective precipitation during Marine Isotope Stage (MIS) 5 due to a larger increase in evapotranspiration than in monsoonal precipitation in response to higher temperature. The greater response of the effective precipitation to temperature than summer monsoon intensity during MIS 5 thus suggests the risk of further aridification in the semi‐arid region of East Asia under climate warming. Plain Language Summary: The potential shortage of water resources in the semi‐arid regions of East Asia under climate warming may pose serious social issues in this highly‐populated area. Projecting changes in water resources in this region requires knowledge of how both monsoonal precipitation and evapotranspiration would respond to a warming climate. Here we present records of effective precipitation and temperature from the East Asian monsoon margins during Marine Isotope Stage (MIS) 5 when a similar degree of warming to future projections has been documented globally. The results show that warm intervals during MIS 5 were characterized by strong summer monsoon conditions but low effective precipitation, indicating greater response of evapotranspiration than monsoonal precipitation to climate warming. Our results thus suggest the possibility of water shortages in the future semi‐arid region of East Asia. Key Points: Microcodium Sr/Ca ratio is a proxy for effective precipitation while microcodium 87Sr/86Sr is sensitive to local temperatureEvolution of both effective precipitation and temperature during Marine Isotope Stage (MIS) 5 has been reconstructedEffective precipitation in the East Asian monsoon margins is controlled by both temperature and monsoonal precipitation amount during MIS 5 [ABSTRACT FROM AUTHOR]

One manifestation of the glaring lack of equality, diversity, and inclusion in higher education relates to the underrepresentation of certain individuals and/or regions in the scholarly publication process. Here, we analyse the affiliations of editorial board members in 126 Geography journals. Specifically, we examine editorial board membership by region and determine the extent to which the regional representation of editorial board members is associated with journal impact factor as a measure of journal reach and quality. Of the 5,202 editorial board members examined, almost 80% are located in mainland Europe, North America, and the British Isles, while roughly five percent are located in Central America, South America, the Middle East, and Africa combined. Moreover, editorial board members located in these four regions from the Global South are most often editorial board members of journals in the lowest quartile (by impact factor). These findings highlight the outdated and exclusionary practices that pervade the scholarly publication process in science in general, and Geography specifically. [ABSTRACT FROM AUTHOR]

Questions: Species distribution models have traditionally relied heavily on temperature and precipitation, often ignoring other potentially important variables. However, recent advances have shown other climatic variables, including snow cover and solar radiation, may strongly improve predictions of species occurrence. Wind has long been known to have mechanical and physiological impacts on plants, but has not yet received adequate attention as a driver of species distributions. Location: Marion Island, sub‐Antarctic. Methods: Using data from 1,440 plots in a chronically windy system, we test if wind stress (a combination of wind exposure and wind speed) improves species distribution models of vascular plant species, examining predictions for both species occurrence and cover. Results: Wind stress was a significant predictor of the occurrence of 12 of the 16 species, even after accounting for seven other ecophysiologically important abiotic variables. Species showed differential responses to wind, but wind stress was among the four most important drivers for the majority of species when modelling occurrence patterns (10 of 16) and variation in cover (12 of 16). Further, wind stress was more important than all temperature and precipitation variables in predicting the occurrence of six species (and three species' cover). Conclusions: Wind conditions were most influential for species that are characteristic of open, wet environments and for pteridophyte species, likely due to high wind speeds and exposure increasing the potential for moisture loss. This research highlights the value of incorporating wind metrics into species distribution models, particularly under changing wind patterns. [ABSTRACT FROM AUTHOR]

Background: Open access (OA) implies free and unrestricted access to and re-use of research articles. Recently, OA publishing has seen a new wave of interest, debate, and practices surrounding that mode of publishing. Objectives: To provide an overview of publication practices and to compare them among six countries across the world to stimulate further debate and to raise awareness about OA to facilitate decision-making on further development of OA practices in earth sciences. Methods: The number of OA articles, their distribution among the six countries, and top ten journals publishing OA articles were identified using two databases, namely Scopus and the Web of Science, based mainly on the data for 2018. Results: In 2018, only 24%-31% of the total number of articles indexed by either of the databases were OA articles. Six of the top ten earth sciences journals that publish OA articles were fully OA journals and four were hybrid journals. Fully OA journals were mostly published by emerging publishers and their article processing charges ranged from $1000 to $2200. Conclusions: The rise in OA publishing has potential implications for researchers and tends to shift article-processing charges from organizations to individuals. Until the earth sciences community decides to move away from journal-based criteria to evaluate researchers, it is likely that such high costs will continue to maintain financial inequities within this research community, especially to the disadvantage of researchers from the least developed countries. However, earth scientists, by opting for legal selfarchiving of their publications, could help to promote equitable and sustainable access to, and wider dissemination of, their work. [ABSTRACT FROM AUTHOR]

Mauritius is a Small Island Developing State (SIDS) with a high population density and increasing agricultural, urban and infrastructural demands, superimposed over limited physical resources. Soil and coastal erosion are recognized as an important environmental challenge facing the island. Here we review the studies on soil erosion over the past two decades and more recent advances in understanding the coastal erosion dynamics. Soil erosion studies have focussed on catchment erosion rates using recognized modelling techniques that have also permitted the mapping of erosion risk for the island. Rainfall assessments using six-minute rainfall data have detailed erosivity conditions for a section of the island but these findings still need to be incorporated into island-scale models. On Round Island, an off-shore Nature Reserve, erosion forms and rates have been measured in support of conservation and restoration programmes. Along the coastline, erosion had been long-recognized as a concern, particularly where development encroaches on the shoreline, and ongoing monitoring is assisting in understanding coastal sediment changes. Further research opportunities are noted and these include a coastal vulnerability assessment and modelling catchment sediment source-sink attributes where there is an impact on lagoon and coral structures. Climate-change scenarios, notably the effects on rainfall erosivity and sea level, are still to be incorporated in studies. [ABSTRACT FROM AUTHOR]

Round Island, a small (219‐ha) volcanic island 22.5 km north of Mauritius, has steep slopes and thin soils. This small tropical island was previously subjected to overgrazing by goats and rabbits, which detrimentally affected ecosystem functioning. Classified as a nature reserve since 1957, Round Island houses the last remnant of palm savannah that has been lost on mainland Mauritius and is a refuge to several endemic and endangered species. Landscape restoration and ecosystem functioning on Round Island are key conservation objectives, but soil erosion remains a significant hindrance to habitat restoration and ecosystem functioning. Here, we investigate soil erosion on Round Island and assess the implications for conservation and management. Sediment movement was monitored monthly (2015–2018) at seven soil erosion plots coupled with rainfall and erosivity measurements. A mean annual sediment movement rate of 0.2136 t ha−1 yr −1 is calculated. Although this rate of sediment movement is low for humid tropical regions, the barren landscape and low contemporary rates of soil erosion suggest that most of the erodible soil has already been eroded. Interrill erosion of the shallow soils and friable parent material is closely correlated with rainfall erosivity and exacerbated by limited vegetation cover. Continued revegetation is recommended to retard soil erosion and restore ecosystem functioning. The paper also emphasises that rainstorms are the greatest single phenomena affecting earth surface processes on and around the island of Mauritius. As such, long‐term monitoring of the interaction between the surface and climate is required to provide insights for conservation management. [ABSTRACT FROM AUTHOR]

Concentrations of major ions in stream water from the Soft Plume River on Subantarctic Marion Island were measured. During the annual relief voyage, samples were collected daily over a 16-day period (21 April–6 May 2015) from three sites along the stream to better understand temporal and spatial variability of stream water chemistry on the island. The chemical composition of the stream is dominated by the sea salts Na+ and Cl−. Mean solute concentrations for Na+ and Cl− are 7 ± 0.58 and 12.5 ± 0.84 mg/L, respectively. The mean molar Na:Cl ratio for all samples is 0.86 ± 0.05, with a range from 0.71 to 0.99 (n = 47), and there is a strong, significant positive correlation between Na+ and Cl− concentrations (r = 0.80; p < 0.001). These values are consistent with previous studies from Marion Island and other Subantarctic islands. Temporal variation in ion concentrations was small. The largest detected change was a decrease in most solute concentrations that coincided with two precipitation events. This decrease was largest at the highest altitude and the shallowest site, suggesting that there was more rainfall at this location. These findings confirm the dominance of the surrounding ocean as the main source of the island’s stream water chemistry and illustrate spatiotemporal patterns that provide an insight into mechanisms affecting their composition on Subantarctic Marion Island. [ABSTRACT FROM AUTHOR]

Weather-related delays in the aviation sector will always occur; however, through effective delay management, the impact and duration of delays can be reduced. Part of delay management is thoroughly assessing adverse weather risks. A weather impact index was specifically designed for O. R. Tambo International Airport, in Kempton Park, South Africa, the busiest airport in Africa, in order to identify the level of risk forecasted adverse weather will have on departure delays. The index is based on a study of all departure delays due to adverse weather over the aerodrome for the period 2010-13. The index is marked for use on 30-h terminal aerodrome forecasts (TAFs) as a planning tool. [ABSTRACT FROM AUTHOR]

South Africa has undergone transformation since the end of apartheid governance in 1994. Legislatively enforced, this transformation has permeated most sectors of society, including higher education. Questions remain, however, about the extent to which transformation has occurred in Higher Education Institutions (HEIs) in general, and across the academic staff body in HEIs in particular. In this study, we examine the transformation of academic staff profiles at HEIs throughout the country. Initially, we graph the racial profile of academics across multiple positions (junior lecturer to professor) from 2005 to 2013. We then use correlational analysis to identify which characteristics of universities in South Africa can be used to explain the racial inequities evident in South African HEIs. Our results indicate that world university ranking; percentage black African staff; percentage black African student body; and whether the university is ‘historically disadvantaged’, all influence the racial profile of the academic staff body to varying degrees. The size of the overall staff and study body does not appear to influence the racial profile of universities’ staff component. We conclude that transformation of the academic staff body of HEIs in South Africa is indeed occurring, albeit slowly. Rather than seeing this as a negative, we argue that the pace of ‘academic’ transformation in the country needs to be interpreted within the framework of academic governance. [ABSTRACT FROM AUTHOR]