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Open access

Elisabeta Simona Catană

Abstract

The essay analyses Graham Swift’s Waterland and shows that history and identity are subject to a process of reconstruction within stories which evince their author’s power to build on the past based on his vision and cultural experience. We associate the process of recreating the world of the past through stories with the process of recreating a new world through siltation. The same as silt develops land and a new world on the already existing pieces of land reclaimed from water, stories reconstruct history and the past. Both silt and stories reconstruct the past.

Open access

Claudio O. Delang

Abstract

More than 40% of China’s arable land is degraded. This paper reviews the direct and indirect consequences of soil degradation in China. Soil degradation has observable and measurable impacts, which include soil nutrient loss, salinization, acidification, and desertification. It also has a number of indirect consequences, in particular, a reduction of the agricultural output due to a drop in soil nutrient; an increase in the frequency and magnitude of floods and landslides; a decline in livestock production due to a decrease in grass density available to roaming livestock; an intensification of dust storms and sandstorms which affects health, the productivity of the land, and visibility; and a faster accumulation of silt in dams, which damages their structure, reduces their water storage capacity, and compromises their original functions, in particular their electricity generation capacity.

Open access

Zhongping Lai and Helmut Brückner

multiplegrain aliquots. Radiation Measurements 38(2): 241-252, DOI 10.1016/j.radmeas.2003.10.001. Lai Z-P, Brückner H, Zöller L and Fülling A, 2007b. Existence of a common growth curve for silt-sized quartz OSL of loess from different continents. Radiation Measurements 42(9): 1432-1440, DOI 10.1016/j.radmeas.2007.08.006. Lai Z-P, Brückner H, Zöller L and Fülling A, 2008. The effect of thermal treatment on the growth curve shape for OSL of quartz extracted from Chinese loess. Radiation Measurements , in press, DOI 10

Open access

Marian Mokwa and Beata Malczewska

The silting influence on the capacity of the Krzywaniec reservoir

The Krzywaniec reservoir is a part of Dychów complex hydraulic engineering, and it was created as a damming up water of the Bóbr river in 42+700 km to wave elevation 73.30 NN. The river valley was divided by three span gate weir and tide gate to derivation channel to ESP Dychów. The Krzywaniec reservoir is currently silted up so that the probable water surface Q1% is going to reach reservoir site embankment which means it poses the flood risk on surrounding area. The authors present restoring the initial situation on Krzywaniec reservoir, and estimated the reduction of flood depending on method of declogging the reservoir using computer simulation performed in HEC-RAS.

Open access

Ahmed Ahmed, Yvan Gariepy and Vijaya Raghavan

Abstract

Biochar is proven to enhance soil fertility and increase crop productivity. Given that the influence of biochar on soil compaction remains unclear, selected physico-mechanical properties of soil amended with wood-derived biochar were assessed. For unamended silt loam, the bulk density, maximum bulk density, optimum moisture content, plastic limit, liquid limit, and plasticity index were 1.05 Mg m-3, 1.69 Mg m-3, 16.55, 17.1, 29.3, and 12.2%, respectively. The penetration resistance and shear strength of the unamended silt loam compacted in the standard compaction Proctor mold and at its optimum moisture content were 1800 kPa and 850 kPa, respectively. Results from amending the silt loam with 10% particle size ranges (0.5-212 μm) led to relative decreases of 18.1, 17.75, 66.66, and 97.4% in bulk density, maximum bulk density, penetration resistance, and shear strength, respectively; a 26.8% relative increase in optimum moisture content; along with absolute increases in plastic limit, liquid limit, and plasticity index of 5.3, 13.7, and 8.4%, respectively. While the biochar-amended silt loam soil was more susceptible to compaction, however, soil mechanical impedance enhanced.

Open access

Samuel Idoko Haruna and Nsalambi Vakanda Nkongolo

Abstract

Soil and crop management practices can affect the physical properties and have a direct impact on soil sustainability and crop performance. The objective of this study was to investigate how soil physical properties were affected by three years of tillage, cover crop and crop rotation treatments in a corn and soybean field. The study was conducted on a Waldron siltyloam soil at Lincoln University of Missouri. Soil physical properties studied were soil bulk density, volumetric and gravimetric water contents, volumetric air content, total pore space, air-filled and water-filled pore space, gas diffusion coefficient and pore tortuosity factor. Results showed significant interactions (p<0.05) between cover crop and crop rotation for bulk density, gravimetric and total pore space in 2013. In addition, cover crop also significantly interacted (p<0.05) with tillage for bulk density and total pore space. All soil physical properties studied were significantly affected by the depth of sampling (p<0.0001), except for bulk density, the pore tortuosity factor and total pore space in 2012, and gravimetric and volumetric in 2013. Overall, soil physical properties were significantly affected by the treatments, with the effects changing from one year to another. Addition of a cover crop improved soil physical properties better in rotation than in monoculture.

Open access

Bogdan Noga, Jan Marjanowski, Henryk Biernat, Stanisław Kulik, Bogusław Zieliński and Arkadiusz Nalikowski

Abstract

The paper presents precipitation results from cold thermal water deposits that are the main cause of clogging in absorbent geothermal wells and borehole areas. As a result of physical and chemical analysis, laboratory tests and observation of the operation of a geothermal installation, a new method was developed to prevent the precipitation of sludge from cooled thermal water. The method being a modification of soft acidising was tentatively named as a super soft acidising method

Open access

Minea Ionuţ, Nica Dragoş and Boca Bogdan

References Bucur D., Savu P., 2006 Considerations for the Design of Intercepting Drainage for Collecting Water from Seep Areas, Journal of Irrigation and Drainage Engineering, Reston, SUA, vol. 132, Issue 6, 597-599. Diaconu C., Serban P. 1994 Hydrological Summarises and Regionalisation, Technical Publishing House Drobot R. 1997, Statistical Basis of Hydrology, Didactic and Pedagogical Publishing House, Bucharest Giurma I. 1997, Reservoir Silting, H.G.A. Publishing House, Bucharest Ichim I

Open access

Youcef Mahmoudi, Abdellah Cherif Taiba, Leila Hazout, Wiebke Baille and Mostefa Belkhatir

behaviour and instability friction angle of normally consolidated and overconsolidated Chlef sand–silt mixture samples (OCR = 1 and 2), focusing on the influence of low plastic fines content (F c = 0%, 20% and 40%). Factors such as degree of saturation, sample size and relative density have been kept constant. A detailed laboratory investigation has been presented in the subsequent sections. 2 Experimental program 2.1 Index properties of tested materials Natural sandy soil material was collected along the banks of Chlef (Algeria) River from liquefied soil

Open access

Angelika Schoder

Abstract

The paper investigates experts’ perceptions of hydropower, sediment regime, and their interaction in the 20th century with an environmental historical approach, based on various case studies at both the Danube River and one of its tributaries, and on a review of contemporary literature authored by engineers. Results show that questions of sediment continuity have engaged planners of hydropower plants since the advent of this technology, and decisions were at any time influenced by multiple interests (navigation, electricity demand, nature conservation). In such an intricate fluvial landscape, phenomena like reservoir sedimentation and riverbed incision can be approached as “legacies” of past technical interventions, which limit the options of current and future river management.