scholarly journals Synergic hydraulic and nutritional feedback mechanisms control surface patchiness of biological soil crusts on tertiary sands at a post-mining site

2014 ◽  
Vol 62 (4) ◽  
pp. 293-302 ◽  
Author(s):  
Thomas Fischer ◽  
Stella Gypser ◽  
Maria Subbotina ◽  
Maik Veste
Keyword(s):  
System Development ◽  
Water Soluble ◽  
Water Infiltration ◽  
Control Surface ◽  
Successional Stage ◽  
Feedback Mechanisms ◽  
Feedback Mode ◽  
Complex Interactions ◽  
Run Off ◽  
Pyrite Weathering

Abstract In a recultivation area located in Brandenburg, Germany, five types of biocrusts (initial BSC1, developed BSC2 and BSC3, mosses, lichens) and non-crusted mineral substrate were sampled on tertiary sand deposited in 1985- 1986 to investigate hydrologic interactions between crust patches. Crust biomass was lowest in the non-crusted substrate, increased to the initial BSC1 and peaked in the developed BSC2, BSC3, the lichens and the mosses. Water infiltration was highest on the substrate, and decreased to BSC2, BSC1 and BSC3. Non-metric multidimensional scaling revealed that the lichens and BSC3 were associated with water soluble nutrients and with pyrite weathering products, thus representing a high nutrient low hydraulic feedback mode. The mosses and BSC2 represented a low nutrient high hydraulic feedback mode. These feedback mechanisms were considered as synergic, consisting of run-off generating (low hydraulic) and run-on receiving (high hydraulic) BSC patches. Three scenarios for BSC succession were proposed. (1) Initial BSCs sealed the surface until they reached a successional stage (represented by BSC1) from which the development into either of the feedback modes was triggered, (2) initial heterogeneities of the mineral substrate controlled the development of the feedback mode, and (3) complex interactions between lichens and mosses occurred at later stages of system development.

Recommended urban storm water infiltration devices for different types of run-off under varying hydrogeological conditions

2008 ◽  
Vol 8 (4) ◽  
pp. 231-238 ◽  
Author(s):  
Patricia Göbel ◽  
Julia Zimmermann ◽  
Christoph Klinger ◽  
Holger Stubbe ◽  
Wilhelm G. Coldewey
Keyword(s):  
Water Infiltration ◽  
Storm Water ◽  
Hydrogeological Conditions ◽  
Run Off ◽  
Different Types ◽  
Urban Storm

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
Keyword(s):  
Water Infiltration ◽  
Clay Soils ◽  
Winter Cereal ◽  
Maximum Slope ◽  
Crop Cover ◽  
Forage Crop ◽  
Run Off ◽  
Alternative Techniques ◽  
Italian Apennines ◽  
Effective Conservation

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.

scholarly journals Training on Water Conservation and Application of Biopori Holes to Farmers of Palm plantation and Vegetable Farming in Bengkulu Province

2019 ◽  
Vol 2 ◽  
pp. 782
Author(s):  
Hery Haryanto
Keyword(s):  
Water Conservation ◽  
Rainy Season ◽  
Organic Waste ◽  
Dry Season ◽  
Water Infiltration ◽  
Stagnant Water ◽  
Training Activity ◽  
Run Off ◽  
Vegetable Farming

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. 

scholarly journals Point observations of liquid water content in natural snow – investigating methodical, spatial and temporal aspects

2010 ◽  
Vol 4 (4) ◽  
pp. 1967-2011 ◽  
Author(s):  
F. Techel ◽  
C. Pielmeier
Keyword(s):  
Water Content ◽  
Liquid Water ◽  
Liquid Water Content ◽  
Temporal Variations ◽  
Swiss Alps ◽  
Water Infiltration ◽  
Small Scale ◽  
Diurnal Changes ◽  
Run Off ◽  
Hand Test

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.

scholarly journals Numerical investigation of the performance of engineered barriers in reducing flood risk

2021 ◽  
Vol 337 ◽  
pp. 04003
Author(s):  
Alexandros L. Petalas ◽  
Aikaterini Tsiampousi ◽  
Lidija Zdravkovic ◽  
David M. Potts
Keyword(s):  
Flood Risk ◽  
Soil Layer ◽  
Urban Environments ◽  
Water Infiltration ◽  
Natural Soil ◽  
Water Storage Capacity ◽  
Run Off ◽  
London Clay ◽  
Parametric Analyses ◽  
Precipitation Events

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.

Declines in Vegetation Patches, Plant Diversity, and Grasshopper Diversity Near Cattle Watering-Points in the Victoria River District, Northern Australia.

1999 ◽  
Vol 21 (1) ◽  
pp. 135 ◽  
Author(s):  
JA Ludwig ◽  
RW Eager ◽  
RJ Williams ◽  
LM Lowe
Keyword(s):  
Surface Roughness ◽  
Plant Diversity ◽  
Plant Species Richness ◽  
Water Infiltration ◽  
Soil Water Storage ◽  
Northern Australia ◽  
Run Off ◽  
Water Point ◽  
Perennial Vegetation ◽  
Vegetation Patches

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

scholarly journals Contribution of dust inputs to dissolved organic carbon and water transparency in Mediterranean reservoirs

2012 ◽  
Vol 9 (12) ◽  
pp. 5049-5060 ◽  
Author(s):  
I. de Vicente ◽  
E. Ortega-Retuerta ◽  
R. Morales-Baquero ◽  
I. Reche
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Western Mediterranean ◽  
Water Soluble ◽  
Water Transparency ◽  
Saharan Dust ◽  
Organic Components ◽  
Western Mediterranean Basin ◽  
Run Off ◽  
Atmospheric Inputs

Abstract. The Mediterranean reservoirs receive frequent atmospheric Saharan dust inputs with soil-derived organic components mostly during the stratification periods, when run-off inputs are particularly limited. Here, we quantified and optically characterized the water-soluble organic carbon (WSOC) of the (dry and wet) atmospheric deposition in collectors placed near three reservoirs from the western Mediterranean Basin. In addition, we determined the WSOC contribution to the pool of dissolved organic carbon (DOC) in the reservoirs and the influence of dust-derived chromophoric organic components on the water transparency during their stratification periods. We found synchronous dynamics in the WSOC atmospheric inputs among the three collectors and in the DOC concentrations among the three reservoirs. The DOC concentrations and the WSOC atmospheric inputs were positive and significantly correlated in the most oligotrophic reservoir (Quéntar) and in the reservoir with the highest ratio of surface area to mixing water depth (Cubillas). Despite these correlations, WSOC atmospheric inputs represented less than 10% of the total DOC pool, suggesting that indirect effects of dust inputs on reservoir DOC may also promote these synchronous patterns observed in the reservoirs. Chromophoric components from dust inputs can significantly reduce the water transparency to the ultraviolet radiation (UVR). The depths where UVR at λ = 320 nm was reduced to ten percent of surface intensity (Z10%) decreased 27 cm in Béznar, 49 cm in Cubillas, and 69 cm in Quéntar due to the dust inputs. Therefore, the increasing dust export to the atmosphere may have consequences for the water transparency of aquatic ecosystems located under the influence of the global dust belt.

scholarly journals Containerized Jeffrey Pine Growth and Nutrient Uptake in Response to Mycorrhizal Inoculation and Controlled Release Fertilization

1997 ◽  
Vol 12 (2) ◽  
pp. 33-40 ◽  
Author(s):  
R. F. Walker ◽  
L. M. Kane
Keyword(s):  
Controlled Release ◽  
System Development ◽  
N Uptake ◽  
Dry Weight ◽  
Water Soluble ◽  
Fertilizer Treatment ◽  
Root System Development ◽  
Jeffrey Pine ◽  
Soluble Fertilizer ◽  
Nutrient Amendment

Abstract Ectomycorrhizal inoculation with basidiospores of Pisolithus tinctorius and fertilization with two controlled release nutrient formulations, High N 24-4-7 and Sierra 16-6-10 Plus Minors, were evaluated for their effects on containerized Jeffrey pine (Pinus jeffreyi) seedlings. Noninoculated and nonfertilized seedlings and a water soluble fertilizer treatment using Peters 20-10-20 provided for comparisons of mycorrhizal and nutrient amendment effects on growth and mineral nutrition. At 6 months, inoculated seedlings had greater root dry weight while fertilization increased shoot dimensions and weight, with the response to controlled release nutrients exceeding that to water soluble fertilizer. After 12 months, inoculation increased mycorrhizal formation, and inoculated seedlings had greater shoot volume as well as root volume, dry weight, and total length. Controlled release fertilization also promoted greater shoot growth than water soluble nutrients at the final measurement, while root system development was comparable overall among fertilized seedlings regardless of nutrient formulation. Foliar analysis revealed that concentrations of most macro- and micronutrients were sufficient for adequate seedling nutrition in all treatments. However, inoculated seedlings exhibited greater uptake of P, Ca, Mg, S, Fe, Mn, and Zn. Fertilization generally increased foliar concentrations of all of the above elements except Mg and Fe, but also increased N uptake. Overall, these results suggest that inoculation with P. tinctorius and controlled release fertilization with High N 24-4-7 and Sierra 16-6-10 facilitate production of Jeffrey pine container stock suitable for outplanting on harsh sites. West. J. Appl. For. 12(2):33-40.

What does the lipoprotein oxidation phenomenon mean?

2004 ◽  
Vol 32 (1) ◽  
pp. 160-163 ◽  
Author(s):  
G.A.A. Ferns ◽  
D.J. Lamb
Keyword(s):  
High Risk ◽  
No Value ◽  
Clinical Intervention ◽  
Epidemiological Studies ◽  
Water Soluble ◽  
Protective Effects ◽  
Lipoprotein Oxidation ◽  
Complex Interactions ◽  
Antioxidant Supplements

The evidence that oxidative lipid modification may be involved in the genesis of common diseases, such as atherosclerosis, is persuasive, but it was, until recently, conjecture based on in vitro findings, or investigation using experimental animal models. Recent clinical intervention studies in patients at high risk of cardiovascular events have been, at best, inconclusive. This has led to a general consensus that antioxidant supplements are of no value in the prevention of cardiovascular disease in subjects at high risk. However, epidemiological studies have demonstrated that the protective effects of antioxidant supplements, specifically vitamin E, were particularly evident amongst healthy subjects taking supplements. The picture is further clouded by the uncertain mechanism of lipoprotein modification within the artery wall, the possibility that some antioxidants may, under certain conditions, become pro-oxidants, the complex interactions between lipid- and water-soluble antioxidants, and the fact that free-radical-mediated events may only be important in the early stages of atherogenesis. Recent results also suggest that the biological efficacy of antioxidants, such as α-tocopherol, may be compromised by the conditions extant within the plaque. It is evidently important that the position on the benefits of antioxidants, whether in food or as supplements, in disease prevention is clarified.

scholarly journals Typology of Farms and Farmers’ Perception of the Effects of Soil and Water Conservation Practices in Northern Burkina Faso

2019 ◽  
pp. 251-265 ◽  
Author(s):  
Pale Siébou ◽  
Coulibaly Zoumité Christ Thierry Stephen ◽  
Yonli Djibril ◽  
Mason C. Stephen ◽  
Prasad P.V. Vara ◽  
...  
Keyword(s):  
Burkina Faso ◽  
Water Conservation ◽  
Small Ruminants ◽  
Water Infiltration ◽  
Soil Productivity ◽  
African Countries ◽  
Beneficial Effects ◽  
Run Off ◽  
Sub Saharan ◽  
White Grain

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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