Differences in root phenology and water depletion by an invasive grass explains persistence in a Mediterranean ecosystem

The paper overviews the analytical studies performed at Politehnica University of Bucharest on the analysis of late phase severe accident phenomena in a Canada Deuterium Uranium (CANDU) plant. The calculations start from a dry debris bed at the bottom of calandria vessel. Both SCDAPSIM/RELAP code and ansys-fluent computational fluid dynamics (CFD) code are used. Parametric studies are performed in order to quantify the effect of several identified sources of uncertainty on calandria vessel failure: metallic fraction of zirconium inside the debris, containment pressure, timing of water depletion inside calandria vessel, steam circulation in calandria vessel above debris bed, debris temperature at moment of water depletion inside calandria vessel, calandria vault nodalization, and the gap heat transfer coefficient.

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Responses of root phenology in ecotypes of Eriophorum vaginatum to transplantation and warming in the Arctic

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.149926 ◽

2021 ◽

pp. 149926

Author(s):

Ting Ma ◽

Thomas Parker ◽

Steven Unger ◽

Jonathan Gewirtzman ◽

Ned Fetcher ◽

...

Keyword(s):

The Arctic ◽

Eriophorum Vaginatum ◽

Root Phenology

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Assessing Soil Loss by Water Erosion in a Typical Mediterranean Ecosystem of Northern Greece under Current and Future Rainfall Erosivity

Water ◽

10.3390/w13152002 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2002

Author(s):

Stefanos Stefanidis ◽

Vasileios Alexandridis ◽

Chrysoula Chatzichristaki ◽

Panagiotis Stefanidis

Keyword(s):

Open Source ◽

Soil Loss ◽

Renewable Resource ◽

Mitigation Strategies ◽

Mitigation Measures ◽

Mediterranean Ecosystem ◽

Rainfall Erosivity ◽

Negative Consequences ◽

Northern Greece ◽

Erosion Risk

Soil is a non-renewable resource essential for life existence. During the last decades it has been threatened by accelerating erosion with negative consequences for the environment and the economy. The aim of the current study was to assess soil loss changes in a typical Mediterranean ecosystem of Northern Greece, under climate change. To this end, freely available geospatial data was collected and processed using open-source software package. The widespread RUSLE empirical erosion model was applied to estimate soil loss. Current and future rainfall erosivity were derived from a national scale study considering average weather conditions and RCMs outputs for the medium Representative Concentration Pathway scenario (RCP4.5). Results showed that average rainfall erosivity (R-Factor) was 508.85 MJ mm ha h−1 y−1 while the K-factor ranged from 0.0008 to 0.05 t ha h ha−1 MJ−1 mm−1 and LS-factor reached 60.51. Respectively, C-factor ranged from 0.01 to 0.91 and P-factor ranged from 0.42 to 1. The estimated potential soil loss rates will remain stable for the near future period (2021–2050), while an increase of approximately 9% is expected by the end of the 21th century (2071–2100). The results suggest that appropriate erosion mitigation strategies should be applied to reduce erosion risk. Subsequently, appropriate mitigation measures per Land Use/Land Cover (LULC) categories are proposed. It is worth noting that the proposed methodology has a high degree of transferability as it is based on open-source data.

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Soil water repellency persistence after recurrent forest fires on Mount Carmel, Israel

International Journal of Wildland Fire ◽

10.1071/wf12063 ◽

2013 ◽

Vol 22 (4) ◽

pp. 515 ◽

Cited By ~ 19

Author(s):

Naama Tessler ◽

Lea Wittenberg ◽

Noam Greenbaum

Keyword(s):

Organic Matter ◽

Soil Water ◽

Forest Fires ◽

Water Drop ◽

Chemical Properties ◽

Water Repellency ◽

Mediterranean Ecosystem ◽

Long Term Effects ◽

Soil Water Repellency ◽

Chemical Properties Of Soils

Variations in forest fires regime affect: (1) the natural patterns of community structure and vegetation; (2) the physico-chemical properties of soils and consequently (3) runoff, erosion and sediment yield. In recent decades the Mediterranean ecosystem of Mount Carmel, north-western Israel, is subjected to an increasing number of forest fires, thus, the objectives of the study were to evaluate the long-term effects of single and recurrent fires on soil water repellency (WR) and organic matter (OM) content. Water repellency was studied by applying water drop penetration time (WDPT) tests at sites burnt by single-fire, two fires, three fires and unburnt control sites. Water repellency in the burnt sites was significantly lower than in the unburnt control sites, and the soil maintained its wettability for more than 2 decades, whereas after recurrent fires, the rehabilitation was more complicated and protracted. The OM content was significantly lower after recurrent than after a single fire, causing a clear proportional decrease in WR. The rehabilitation of WR to natural values is highly dependent on restoration of organic matter and revegetation. Recurrent fires may cause a delay in recovery and reduced productivity of the soil for a long period.

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