The role of Tibetan Plateau lakes in surface water cycle under global changes

Meso-scale weather systems have been identified as major precipitation bearing systems in the Tibetan Plateau (TP) region. They can pose a risk for people's life and livelihoods, by causing flooding, extreme winds and heavy rainfall in the populous downstream regions. As local hydroclimatic conditions and large-scale atmospheric circulation patterns change with global warming, it is important to understand the role of such weather systems and the associated precipitation-producing mechanisms for the regional water cycle. Two important systems which are often named in this context are meso-scale convective systems (MCSs) and Tibetan Plateau vortices (TPVs). MCSs are recognized as cloud clusters that produce large areas of heavy rainfall, while TPVs refer to frequently occurring meso-scale cyclonic vortices around 500 hPa that are initiated over the TP. Only few studies have looked at the relationship between the dynamical disturbances like TPVs and observations of MCSs. We present here the key characteristics of MCSs as observed by satellite observations from the past two decades and compare it to the key characteristics of TPVs identified by minima in relative vorticity in reanalysis data. Further, we explore in what way TPVs and MCSs are linked to each other by focusing on the most extreme cases of both systems. Finally, we discuss the role of large-scale circulation for both TPVs and MCSs and suggest that future research about extreme precipitation around the TP region should focus more on the mechanisms that link together both systems.

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Stomatal responses to environmental variation among Duranta erecta L.

Annals of Plant Sciences ◽

10.21746/aps.2018.7.12.4 ◽

2019 ◽

Vol 7 (12) ◽

pp. 3481

Author(s):

Sneha Sahay ◽

Jyoti Kumar

Keyword(s):

Water Cycle ◽

Stomatal Density ◽

Guard Cells ◽

Environmental Variation ◽

Global Changes ◽

Global Water Cycle ◽

Stomatal Responses ◽

Plant Environment ◽

Different Levels

Stomata are pores found in the epidermis of leaf that allow for consequently water loss through transpiration, pores are bound by specialized cells, called guard cells. Abnormalities present in the stomata such as contiguous stomata, twin stomata are of great importance to the global-water cycle and plant’s ability to respond to environmental variation. Elevation of atmospheric carbon di-oxide concentration often results in lower stomatal density. Inspection of the distribution of stomata in leaves growing in environment with different levels of available water gives clues for the role of stomata in plant adaptation. The plant environment is continuously changing, and stomatal apertures are perceived by the guard cells. They adapt to local and global changes on all timescales from minute to millennia.

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Role of the Early Miocene Jinhe-Qinghe Thrust Belt in the building of the Southeastern Tibetan Plateau topography

Tectonophysics ◽

10.1016/j.tecto.2021.228871 ◽

2021 ◽

Vol 811 ◽

pp. 228871

Author(s):

Chengyu Zhu ◽

Guocan Wang ◽

Philippe Hervé Leloup ◽

Kai Cao ◽

Gweltaz Mahéo ◽

...

Keyword(s):

Tibetan Plateau ◽

Early Miocene ◽

Thrust Belt ◽

Southeastern Tibetan Plateau

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Biofouling by ultra-low pressure filtration of surface water: The paramount role of initial available biopolymers

Journal of Membrane Science ◽

10.1016/j.memsci.2021.119740 ◽

2021 ◽

Vol 640 ◽

pp. 119740

Author(s):

Li Zhang ◽

Nigel Graham ◽

Nicolas Derlon ◽

Youneng Tang ◽

Muhammad Saboor Siddique ◽

...

Keyword(s):

Surface Water ◽

Low Pressure ◽

Pressure Filtration

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Effects of Fe addition on sediment P dynamics in a eutrophic lake

10.5194/egusphere-egu21-4941 ◽

2021 ◽

Author(s):

Melanie Münch ◽

Rianne van Kaam ◽

Karel As ◽

Stefan Peiffer ◽

Gerard ter Heerdt ◽

...

Keyword(s):

Water Quality ◽

Organic Matter ◽

Surface Water ◽

Water Column ◽

Sediment Cores ◽

Surface Water Quality ◽

Water Interface ◽

Eutrophic Lakes ◽

Fe Addition

The decline of surface water quality due to excess phosphorus (P) input is a global problem of increasing urgency. Finding sustainable measures to restore the surface water quality of eutrophic lakes with respect to P, other than by decreasing P inputs, remains a challenge. The addition of iron (Fe) salts has been shown to be effective in removing dissolved phosphate from the water column of eutrophic lakes. However, the resulting changes in biogeochemical processes in sediments as well as the long-term effects of Fe additions on P dynamics in both sediments and the water column are not well understood.In this study, we assess the impact of past Fe additions on the sediment P biogeochemistry of Lake Terra Nova, a well-mixed shallow peat lake in the Netherlands. The Fe-treatment in 2010 efficiently reduced P release from the sediments to the surface waters for 6 years. Since then, the internal sediment P source in the lake has been increasing again with a growing trend over the years.In 2020, we sampled sediments at three locations in Terra Nova, of which one received two times more Fe during treatment than the other two. Sediment cores from all sites were sectioned under oxygen-free conditions. Both the porewaters and sediments were analysed for their chemical composition, with sequential extractions providing insight into the sediment forms of P and Fe. Additional sediment cores were incubated under oxic and anoxic conditions and the respective fluxes of P and Fe across the sediment water interface were measured.The results suggest that Fe and P dynamics in the lake sediments are strongly coupled. We also find that the P dynamics are sensitive to the amount of Fe supplied, even though enhanced burial of P in the sediment was not detected. The results of the sequential extraction procedure for P, which distinguishes P associated with humic acids and Fe oxides, as well as reduced flux of Fe(II) across the sediment water interface in the anoxic incubations, suggest a major role of organic matter in the interaction of Fe and P in these sediments.Further research will include investigations of the role of organic matter and sulphur in determining the success of Fe-treatment in sequestering P in lake sediments. Based on these data in combination with reactive transport modelling we aim to constrain conditions for successful lake restoration through Fe addition.

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Role of Lateral Terrestrial Water Flow on the Regional Water Cycle in a Complex Terrain Region: Investigation With a Fully Coupled Model System

Journal of Geophysical Research Atmospheres ◽

10.1029/2018jd029004 ◽

2019 ◽

Vol 124 (2) ◽

pp. 507-529 ◽

Cited By ~ 7

Author(s):

Thomas Rummler ◽

Joel Arnault ◽

David Gochis ◽

Harald Kunstmann

Keyword(s):

Water Flow ◽

Complex Terrain ◽

Water Cycle ◽

Coupled Model ◽

Model System ◽

Terrestrial Water ◽

Fully Coupled ◽

Regional Water

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Using insect natural history collections to study global change impacts: challenges and opportunities

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2017.0405 ◽

2018 ◽

Vol 374 (1763) ◽

pp. 20170405 ◽

Cited By ~ 18

Author(s):

Heather M. Kharouba ◽

Jayme M. M. Lewthwaite ◽

Rob Guralnick ◽

Jeremy T. Kerr ◽

Mark Vellend

Keyword(s):

Natural History ◽

Global Change ◽

Global Changes ◽

Genomic Information ◽

Theme Issue ◽

The Past ◽

Natural History Collections ◽

Global Change Research ◽

Challenges And Opportunities

Over the past two decades, natural history collections (NHCs) have played an increasingly prominent role in global change research, but they have still greater potential, especially for the most diverse group of animals on Earth: insects. Here, we review the role of NHCs in advancing our understanding of the ecological and evolutionary responses of insects to recent global changes. Insect NHCs have helped document changes in insects' geographical distributions, phenology, phenotypic and genotypic traits over time periods up to a century. Recent work demonstrates the enormous potential of NHCs data for examining insect responses at multiple temporal, spatial and phylogenetic scales. Moving forward, insect NHCs offer unique opportunities to examine the morphological, chemical and genomic information in each specimen, thus advancing our understanding of the processes underlying species’ ecological and evolutionary responses to rapid, widespread global changes. This article is part of the theme issue ‘Biological collections for understanding biodiversity in the anthropocene’.

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