Energy Dispersive X-Ray Spectroscopy of the Sohnari Member of Laki Formation from Southern Indus Basin of Pakistan

This study determines the geochemical and depositional environment analysis of the sediments of the Sohnari Member of the Laki Formation, Northern Kirthar Fold Belt of Pakistan. The Energy-Dispersive-X-Ray Spectroscopy (EDS) technique is used for the detection of major elements and the effects of shifting depositional climatic conditions of six representative samples which were acquired from the Sohnari Member of the Laki Formation at Lakhra area, Sindh, Pakistan. The sedimentological studies clarify that the sediments the Sonahri Member are relatively immature and most migrated in clastic mode. The availability of Silica shows that the Member was formed due to biochemical precipitation and detrital mode and was deposited at a fast rate of sediment deposition under the fluvio-deltaic depositional system. This is also deduced that the rapid rate of sediment deposition might be created a reducing atmosphere and allowing for the mineralization of sulphur.

Experimental study on the effects of multiple factors on spring meltwater erosion on an alpine meadow slope

Meadow degradation provides a major indication of increased soil erosion in alpine regions.Serious soil erosion is observed during the spring in particular because soil thawing coincides with the period of snowmelt and the meadow coverage is very low at this time.Studies relating to soil erosion caused by spring meltwater are,however,limited and controversial.Therefore,a field experimental study was conducted in a typical meadow in the Binggou watershed on the northern edge of the Tibetan Plateau to assess the impact of multiple factors on spring meltwater erosion on an alpine meadow slope.The multiple factors included three flow rates(1,2,and 3 L/min),four slope gradients(10°,15°,20°,and 25°),and three underlying surface conditions(meadow,disturbed meadow,and alluvial soil).An equal volume of concentrated meltwater flow was used in all experiments.The results showed that rapid melting at a high flow rate could accelerate soil erosion;as the flow rate increased from 1 to 3 L/min,the total surface runoff increased by a factor of 0.7 and the total sediment yield increased by more than 6-fold.The in-fluence of the slope gradient on the amount of runoff was positively linear and the influence was relatively low;when the slope increased from 10°to 25°,the total runoff only increased by 16%.However,the slope gradient had a strong impact on soil erosion.The total sediment yield doubled when the slope increased from 10°to 20°and then slightly decreased at 25°.The meadow could effectively reduce soil erosion,although when the meadow was disturbed,the total runoff increased by 60%and the sediment yield by a factor of 1.5.The total runoff from the alluvial soil doubled in comparison to the meadow,while the sediment yield increased nearly 7-fold.The findings of this study could be helpful to understand the characteristics and impact of multiple controlling factors of spring meltwater erosion.It also aims to provide a scientific basis for an improved management of alpine meadows as well as water and soil conservation activities in high-altitude cold regions.