The management of clay soils on hilly land: a model for a Mediterranean environment

1979 ◽  
Vol 10 (1) ◽  
pp. 5-12 ◽  
Author(s):  
G C Chisci

Clay soils of the Italian Apennines are subject to erosion and landslides. Up-and-down-slope deep ploughing in preparation for the winter cereal crop can aggravate such erosion. Alternative techniques are minimum tillage which enhances water infiltration, the use of soil conditioners, and tile drainage transversely to the maximum slope to control run-off. But the provision of a legume forage crop cover probably represents the most generally effective conservation measure.

2013 ◽  
Vol 1 (No. 1) ◽  
pp. 16-22
Author(s):  
Kodešova Radka ◽  
Šimůnek Josef Kozak and Jiři

The single-porosity and dual-permeability models in HYDRUS-1D (Šimůnek et al. 1998, 2003) were used to simulate variably-saturated water movement in clay soils with and without macropores. Numerical simulations of water flow for several scenarios of probable macropore compositions show a considerable impact of preferential flow on water infiltration in such soils. Preferential flow must be considered to predict water recharge in clay soils.


2008 ◽  
Vol 8 (4) ◽  
pp. 231-238 ◽  
Author(s):  
Patricia Göbel ◽  
Julia Zimmermann ◽  
Christoph Klinger ◽  
Holger Stubbe ◽  
Wilhelm G. Coldewey

2014 ◽  
Vol 29 (4) ◽  
pp. 557-571 ◽  
Author(s):  
Ryan D. Stewart ◽  
Majdi R. Abou Najm ◽  
David E. Rupp ◽  
John W. Lane ◽  
Hamil C. Uribe ◽  
...  
Keyword(s):  

2015 ◽  
Vol 27 (4) ◽  
pp. 505-510 ◽  
Author(s):  
Jin-Hee Ryu ◽  
Young-Joo Kim ◽  
Su-Hwan Lee ◽  
Yang-Yeol Oh ◽  
Young-Doo Kim ◽  
...  

2019 ◽  
Vol 2 ◽  
pp. 782
Author(s):  
Hery Haryanto

This essay is a summary of training activity of water conservation and application of biopori holes at two villages in Bengkulu Province, i.e. Pering Baru village surrounded by palm cultivation, Suro Lembak dominated by vegetable farming. Both villages were experienced  with shortage of water during dry season, and plenty of water during rainy season. So people from both villages were eager to be trained on water conservation and implementation of biopori hole. Water conservation in palm plantation and vegetable farming were done by making ditches perpendicular with the slope of lands in order to collect run off water, and lead to infiltration. Moreover,  biopori holes could be constructed  around their homes in order to increase water infiltration, and also to be used as organic waste digester for producing composts. This biopori holes protected  from malaria diseases due to no more stagnant water. 


2010 ◽  
Vol 4 (4) ◽  
pp. 1967-2011 ◽  
Author(s):  
F. Techel ◽  
C. Pielmeier

Abstract. Information on the amount and distribution of liquid water in the snowpack is important for forecasting wet snow avalanches and predicting melt-water run-off. Considerable spatial and temporal variations of snowpack wetness exist. Currently, available information relies mostly on point observations. Often, the snow wetness is estimated manually using a hand test. However, quantitative measures are also applied. We compare the hand test to quantitative measurements and investigate temporal and small-scale spatial aspects of the snowpack wetness. For this, the liquid water content was measured using dielectric methods, with the Snow Fork and Denoth wetness instrument in the Swiss Alps, mostly above tree-line. More than 12 000 water content measurements were observed on 30 days in 85 locations. The qualitative hand test provides an indication of snowpack wetness, although snowpack wetness is often over-estimated and quantitative water content measurements are more reliable. If the measured water content is very low, it is unclear if the snow is dry or contains small quantities of liquid water. In particular during the initial melt-phase, when the snowpack is only partially wet, it is important to consider spatial aspects when interpreting point observations. One measurement taken at a certain measurement depth may significantly deviate in 10–20% of the cases from snowpack wetness in the surrounding snow. Not surprisingly, diurnal changes in snowpack wetness are significant in layers close to the snow surface. At depth, changes were noted within the course of a day. From a single vertical profile, it was often unclear if these changes were due to the heterogeneous nature of water infiltration. Based on our observations, we propose to repeat three measurements at horizontal distances greater than 50 cm. This approach provides representative snow wetness information for horizontal distances up to 5 m. Further, we suggest a simplified classification scheme of snowpack wetness by introducing five wetness types of the snowpack incorporating both vertical and horizontal liquid water content distribution.


2021 ◽  
Vol 337 ◽  
pp. 04003
Author(s):  
Alexandros L. Petalas ◽  
Aikaterini Tsiampousi ◽  
Lidija Zdravkovic ◽  
David M. Potts

In this paper, 2-dimensional, hydro-mechanically coupled finite element analyses are performed to assess the performance of an engineered barrier aimed at reducing flood risk in urban environments. The barrier consists of an unsaturated compacted soil layer and a drainage layer of a coarse granular material, constructed on top of the natural soil, in this case London clay. The barrier is vegetated so that its water storage capacity is renewed after each rainfall event. Sophisticated boundary conditions are used to simulate the effect of precipitation and evapotranspiration. The rainfall water infiltration and the initiation of water run-off during intense precipitation events are simulated. The effect of the hydraulic properties of the unsaturated soil layer on the performance of the system is investigated by means of parametric analyses. The effect of precipitation rate and geometry of the barrier is also discussed. Design recommendations for the properties of the compacted layer and the dimensions of the system are given at the end of the paper.


1999 ◽  
Vol 21 (1) ◽  
pp. 135 ◽  
Author(s):  
JA Ludwig ◽  
RW Eager ◽  
RJ Williams ◽  
LM Lowe

In this study, we quantify the density, cover and obstruction width of vegetation patches, the roughness of landscape surfaces, and the diversities of plants and grasshoppers with distance from cattle watering- points. We used distance from water as a surrogate for a gradient in grazing pressure. Fourteen study sites were located in the Victoria River District of northern Australia, seven from a water point on Kidman Springs Station on calcareous red loam soils and seven from a water point at Mount Sanford Station on craclcing-clay black soils. At each study site transect lines were oriented within the landscape to run downslope (i.e. in the direction of flows of run-off). We measured the intercept length and obstruction width of perennial vegetation patches along these lines. Plant diversity was measured in quadrats positioned along each line and grasshopper diversity was determined by species counts on each site. We also surveyed the roughness of the landscape surface along each line. A rough surface will tend to slow run-off. hence increase time for water infiltration and soil-water storage. Surface roughness declined near water, as did the density, cover and obstruction width of perennial vegetation patches. Grasshopper and plant species richness also declined near water. These declines suggest strong linkages between landscape filmtion. biodiversity and inipacts of cattle grazing and trampling. Cattle will always create 'sacrifice zones' around watering-points. However, the area of this impact on function and diversity can be minimised by managing the timing and intensity of paddock use. Key words: grazing gradients. Kidman Springs, landscape function. Mount Sanford, piosphere, surface roughness, tropical grasslands, tropical savannas


2019 ◽  
pp. 251-265 ◽  
Author(s):  
Pale Siébou ◽  
Coulibaly Zoumité Christ Thierry Stephen ◽  
Yonli Djibril ◽  
Mason C. Stephen ◽  
Prasad P.V. Vara ◽  
...  

The continuous degradation of agroecosystem is a major concern for Sub-Saharan African countries, particularly Burkina Faso. To fight against this agroecosystem degradation, SWC such as stone rows, grass strips, zaï, filtering dikes, half-moons and agroforestry had been introduced in the Yatenga Province in Northern Burkina Faso several decades ago. Decades after introduction of SWC practices, a survey was conducted with 120 farmers equally distributed in four villages in the region to learn the farmers’ perceptions of the effects of these practices on their farms. Results revealed a higher proportion of men in the study sites (63%) compared to women. The largest difference in proportions between surveyed men and women was observed in Bogoya where only 22% of the surveyed persons were women. The average years of the respondents across villages was 53 years with 57% of farmers being members of at least one farmer organization. The proportion of educated farmers was 73% and those who received training in SWC techniques represented 36%. Results indicated that white grain sorghum and pearl millet were the main crops produced by 95% of farmers and stone rows and zaï were the dominant SWC techniques used by 77-80% of farmers. Data from the survey indicated a fairly high proportion of big ruminant breeders and small ruminant breeders as well. In fact, 79% of farmers bred big ruminants and 78% bred small ruminants. The main beneficial and direct effects of SWC techniques perceived by farmers was their capacity to improve soil fertility, recover soil, reduce water run-off, and allow good water infiltration in the field, thus improving soil productivity. Farmers pointed out indirect effects of SWC practices on livestock by the regeneration and increase of grass, tree and small shrub biomass available to improve animal growth and health. However, some farmers commented that the long-term use of zaï could lead to soil degradation. The study showed that farmers did perceive the beneficial effects of SWC practices and that greater extension and adoption will only be achieved if they could still receive training, financial and equipment supports.


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