scholarly journals Spring Characteristics and Hydrological Models of Catchments

1986 ◽  
Vol 17 (1) ◽  
pp. 1-20 ◽  
Author(s):  
Jens-Olaf Englund
Keyword(s):  
Shallow Groundwater ◽  
Soil Surface ◽  
Potassium Nitrate ◽  
Natural Ecosystem ◽  
Infiltration Capacity ◽  
Quaternary Deposits ◽  
Main River ◽  
Calcium Magnesium ◽  
High Infiltration

The Åstdalen catchment (373 km2) represents largely a natural ecosystem, typical for the higher central and southern parts of the Scandinavian Peninsula. It is underlain by fractured sedimentary rocks with a thin cover of unconsolidated Quaternary deposits. The runoff process in Åstdalen is mainly determined by: Large accumulation of precipitation as snow, large areas covered by peatlands, and a high waterstorage capacity in the bedrocks. Groundwater discharge occurs in river beds, in springs and as flow towards the soil surface, especially toward peatland areas. The discharges of the main river Åsta and of investigated springs rise rapidly following snowmelt and rainstorms during the two water-years of study, 1 October 1980 to 30 September 1982. This shows that the catchment has a high infiltration capacity, and that water moves rapidly downslope in the saturated zone, following macropores in soils, peatlands and bedrock fractures. Groundwater, especially shallow groundwater, plays an important role of streamflow peak generation, even during snowmelt. About 60-70 % of the river discharges during the melting periods in 1981 and 1982 were baseflow. There is a net gain of protons, ammonium, potassium, nitrate and chloride to the catchment from the atmosphere during the year, and a net loss of calcium, magnesium sodium and sulfate. Constituents showing a net loss have an internal geologic and/or organic source in addition to the atmosphere. The concentration of most substances in river Åsta and in the investigated springs are lowered during peak flows. The concentration of protons is on the other hand typically increased during snowmelt. This indicates that fresh rain and/or snowmelt water dominates such flow periods and not older prestorm water. About 56 % of the protons needed to supply the weathering-derived ions to river Åsta come from precipitation.

scholarly journals Water infiltration in the Brazilian tropical savanna: the case of Cerrado típico

2020 ◽  
Vol 8 (3) ◽  
pp. 165-171
Author(s):  
Felipe Pereira de Lima ◽  
Frederico Piontkowski de Souza Almeida ◽  
Sérgio Fernandes Mendonça Filho ◽  
Johnny Rodrigues de Melo Murta ◽  
Gleicon Queiroz de Brito ◽  
...  
Keyword(s):  
Soil Surface ◽  
Water Source ◽  
Water Infiltration ◽  
Vegetation Types ◽  
Infiltration Capacity ◽  
Distrito Federal ◽  
Surface Permeability ◽  
High Infiltration ◽  
Resistance To Penetration ◽  
Hydrological Functioning

The Brazilian savanna, regionally known as Cerrado is an important water source due to its spatial position in the highlands known as Planalto Central of Brazil. Yet, the hydrological functioning of such complex ecosystems and its many variations is poorly understood. In this paper, we characterized the soil surface permeability to water under in one of the most common vegetation types: the Cerrado típico which is a type of savanna. In doing so, we measured infiltration capacity using the Mini-Disk infiltrometer (n = 15) and soil resistance to penetration using the Stolf penetrometer (n = 7) in a Latossolo (oxisol) under Cerrado típico located in Brasília (Planaltina), Distrito Federal, Brazil. Our  results indicated a high infiltration capacity under Cerrado típico which is potentially associated with a low penetration resistance. This fact might highlight the importance of the natural undisturbed ecosystems, in this case Cerrado típico, as a land-cover which favors hydrological processes which, in turn, promotes soil-groundwater recharge that are inportant to maintain water bodies and reservoirs in the region.

Linking slopes to the wetland: The relevance of interflow processes for water and nutrient input to an inland valley wetland in Uganda

2020 ◽  
Author(s):  
Claudia Schepp ◽  
Bernd Diekkrüger ◽  
Mathias Becker
Keyword(s):  
Land Use ◽  
Soil Water ◽  
Sandy Loam ◽  
Shallow Groundwater ◽  
Soil Surface ◽  
Shallow Aquifer ◽  
Nitrate Content ◽  
Small Scale ◽  
Infiltration Capacity ◽  
Inland Valley

<p>Due to their prolonged water availability wetlands are of increasing importance for small scale agriculture in East Africa. In the inundating landscape of central Uganda, inland valley wetlands are a common landscape unit with high potential for crop cultivation year-round. Yet little is known about the hydrological processes which bring out these favourable conditions. This study focusses on the relevance of interflow processes from the slopes into the wetland regarding water and nutrient delivery from different land use types. Hereby special attention is given to water pathways at the transition from upland geology to valley sediments and to nutrient relocation along the slopes.</p><p>Electrical Resistivity Tomography (ERT) was used as a non-invasive method to characterise interflow pathways in the highly variable saprolite geology and for subsurface delineation of the valley sediments. The measurements were complimented by a drilling campaign and infiltration experiments in different depths. Interflow collection pits were installed at the slope toe in order to quantify water and nutrient fluxes towards the wetland during two consecutive years. Additionally, soil moisture and nitrate content in the soil water were quantified at various positions along the slope.</p><p>ERT-imaging supports the hypothesis of a separation between a confined shallow aquifer and the soil water in the wetland sediments. Drilling results and hydrogeochemical analysis of the interflow and this shallow groundwater indicate a connection of the two components via macropores in the upper saprolite at the slope toe. At the same time interflow is transferred to the soil water of the wetland via a sandy loam layer which is found on top of the confining clay-loam layer of the wetland sediments. Both processes are active even during the dry season and therefore water from the interflow is relevant for water storage (shallow aquifer) and agricultural production (soil water) in the wetland.</p><p>Interflow volume and nitrate content both show a fast reaction to rainfall events, while the amount of water and nutrients delivered to the wetland is related to the land-use on the slope. Nitrate content in the soil water on the slopes suggests a relocation of nutrients in the upper soil horizons towards the slope toe. As infiltration capacity of the soil’s A-horizon is higher compared to the B-horizon a second  lateral flow component appears to be present close to the soil surface.</p><p>The results of this study emphasize the relevance of subsurface flow for wetland hydrology and give first explanations of wetland-upland connectivity in a complex saprolite geology.</p>

The Role of Calcium, Magnesium, and Zinc in Carcinogenesis

1986 ◽  
pp. 497-515 ◽  
Author(s):  
Kazimierz S. Kasprzak ◽  
Michael P. Waalkes
Keyword(s):  
Calcium Magnesium

scholarly journals Species Diversity Induces Idiosyncratic Effects on Litter Decomposition in a Degraded Meadow Steppe

2021 ◽  
Vol 9 ◽  
Author(s):  
Iqra Naeem ◽  
Talal Asif ◽  
Xuefeng Wu ◽  
Nazim Hassan ◽  
Liu Yiming ◽  
...  
Keyword(s):  
Species Diversity ◽  
Litter Decomposition ◽  
Incubation Time ◽  
Soil Surface ◽  
Leymus Chinensis ◽  
Natural Ecosystem ◽  
Litter Bags ◽  
Litter Bag ◽  
Decomposition Dynamics ◽  
Litter Mixing

Litter decomposition is a fundamental path for nutrient cycling in a natural ecosystem. However, it remains unclear how species diversity, including richness and evenness, affects the decomposition dynamics in the context of grassland degradation. Using a litter bag technique, we investigated the litter-mixing effects of two coexisting dominant species (Leymus chinensis Lc and Phragmites australis Pa), as monocultures and mixtures with evenness (Lc:Pa) from M1 (30:70%), M2 (50:50%), and M3 (70:30%), on decomposition processes over time (60 and 365 days). The litter bags were placed on the soil surface along a degradation gradient [near pristine (NP), lightly degraded (LD), and highly degraded (HD)]. We found that 1) mass loss in mixture compositions was significantly and positively correlated with initial nitrogen (N) and cellulose contents; 2) litter mixing (richness and evenness) influenced decomposition dynamics individually and in interaction with the incubation days and the degradation gradients; 3) in a general linear model (GLM), nonadditive antagonistic effects were more prominent than additive or neutral effects in final litter and nutrients except for carbon (C); and 4) in nutrients (C, N, lignin) and C/N ratio, additive effects shifted to nonadditive with incubation time. We speculated that the occurrence of nonadditive positive or negative effects varied with litter and nutrients mass remaining in each degraded gradient under the mechanism of initial litter quality of monoculture species, soil properties of experimental sites, and incubation time. Our study has important implications for grassland improvement and protection by considering species biodiversity richness, as well as species evenness.

scholarly journals Study Of Rubber Growth Under Constraint of Pyrite In Tidal Swampy Area

2017 ◽  
Vol 5 (2) ◽  
pp. 1 ◽  
Author(s):  
Charlos Togi Stevanus ◽  
Umi Hidayati ◽  
Thomas Wijaya ◽  
Andi Nur Cahyo
Keyword(s):  
Soil Analysis ◽  
Shallow Groundwater ◽  
Aerobic Condition ◽  
Soil Surface ◽  
Low Ph ◽  
Survey Method ◽  
Water Drainage ◽  
Dry Land ◽  
Nutrient Analysis ◽  
Tidal Swamp

<p><em>Muara Sugihan is one of the tidal swamp areas for rubber plant cultivation in South Sumatera. A preliminary survey of the land suitability in 2012 described that there are two main problems, the shallow groundwater problem and low pH (2,87-3,05) between 40-100 depth that indicates the presence of pyrite layers. In the prior of planting, the water drainage has been done to maintain the water table. However, the water </em><em>drainage was excessive so that water </em><em>table reach 66 cm from soil surface hence </em><em>aerobic condition resulted in oxidation of </em><em>pyrite layer. The method used in this study </em><em>was</em><em> survey method </em><em>consist of</em><em> measur</em><em>ing</em><em> the girth of </em><em>2 years old </em><em>rubber plants and sampling of soil, leaves, and water </em><em>on</em><em> the trench and the river</em><em> which</em><em> indicated </em><em>the presence</em><em> </em><em>o</em><em>f pyrite layers </em><em>o</em><em>n tidal swam</em><em>p area,</em><em> Muara Sugihan. The </em><em>result showed that </em><em>the growth of the rubbe</em><em>r plants was</em><em> </em><em>inhibite</em><em>d</em><em>, where the</em><em> girth </em><em>was</em><em> 10 cm, while on </em><em>optimal </em><em>dry land </em><em>they</em><em> </em><em>normally </em><em>reached 18 cm. Leaf nutrient analysis showed there was deficient of P, K, and Zn, while on soil analysis showed a low P content. </em><em>T</em><em>he </em><em>pyrite was leach from the soil and </em><em>a</em><em>c</em><em>cu</em><em>m</em><em>ulat</em><em>e into water drainage will lead to </em><em>low pH of water. </em><em>This problem can be solved by water management improvement.</em></p><p><em> </em></p>

scholarly journals Morphometric and hydrographie characteristics of torrents of NW Péloponnèse, Greece

2007 ◽  
Vol 40 (4) ◽  
pp. 1578
Author(s):  
M. Pagonas ◽  
N. Kontopoulos
Keyword(s):  
Quantitative Analysis ◽  
Drainage Density ◽  
Main Direction ◽  
Infiltration Capacity ◽  
Drainage Systems ◽  
Total Length ◽  
Fault Systems ◽  
Stream Frequency ◽  
Tectonic Features ◽  
High Infiltration

The study area includes the catchments of Selemnos, Xylokeras and Volinaios torrents, with 456 streams of 277.848 km total length. The pattern is generally dendritic. A quantitative analysis of the drainage systems of the study area was interpreted and then correlated to the fault systems that appear in the area. The main direction of the streams and the tectonic features is WSW-ENE. The drainage density and stream frequency is highly variable as a result of many factors, most important of which is lithology with high infiltration capacity. The number and the length of most streams show divergence of the 1st and 2nd law of Horton since they have dissimilar values from those theoretically expected.

scholarly journals Estimation of Rainfall-Runoff Relationship and Correlation of Runoff with Infiltration Capacity and Temperature Over East Singhbhum District of Jharkhand

2019 ◽  
Vol 9 (2) ◽  
pp. 461-466
Keyword(s):  
Land Surface ◽  
Pearson Correlation ◽  
Meteorological Parameter ◽  
Research Work ◽  
Soil Surface ◽  
Graphical Analysis ◽  
Annual Runoff ◽  
Annual Rainfall ◽  
Rainfall Runoff ◽  
Infiltration Capacity

In meteorology, Precipitation is any product of the condensation of atmospheric water vapor that falls under the gravity, the rainfall being the principal form of precipitation in India. Rainfall is the most important meteorological parameter for hydrology, as it controls the other processes such as infiltration, runoff, detention storage, and evapotranspiration. When precipitation falls over a catchment area, these processes have to be satisfied before precipitation water becomes runoff. Infiltration is the vertically downward flow of rainfall into ground/underground through percolation inside the soil surface and depends on soil-type, porosity, and permeability. Runoff is the flow of rainwater over the land surface that happens when there is an excess of precipitation over an area. Runoff is produced when the rainwater exceeds the infiltration capacity of the soil. The most important relationships for any watershed are the relationship between rainfall and runoff. This relationship depends on some factors such as characteristics of rainfall, runoff, and infiltration. Though the abovementioned factors have a major impact on the volume of runoff, a consistent correlation between rainfall-runoff enables us to increase more confidence in sufficient time for the formulation of appropriate decision making for the local authority. The present research work was undertaken to analyze the correlation between annual rainfall and annual runoff for the years 1901-2018 over Jamshedpur of East Singhbhum district, Jharkhand. Further in this study, the correlation between infiltration and annual runoff was analyzed over the same area and the same data period. Correlation between temperature and annual runoff was also found. Through the graphical analysis, it was found that the value of annual rainfall and runoff are strongly correlated.As the value of the Pearson correlation coefficient (r) is almost equal to +1 which is a nearly perfect positive correlation, signifies that both variables move in the same direction. It also signifies that the two variables being compared have a perfect positive relationship; that means these two are strongly related. Through the study, it was also found that the infiltration and runoff are largely correlated. There was practically no correlation found between the values of temperature and runoff over the years.

On the Origin of the Spices (and Other Foodstuffs)

2019 ◽  
Author(s):  
Alan Kelly
Keyword(s):  
Primary Production ◽  
Food Chain ◽  
Chemical Elements ◽  
Raw Materials ◽  
Biological Effects ◽  
Desirable Outcome ◽  
Starting Point ◽  
Calcium Magnesium ◽  
Good Starting Point

The beginning of the story of food is what is termed food production. This might sound logically like the process of making food, such as a chef or food company might, but this term is rather generally used in food science to refer to the so-called primary production of food, from growth of crops to harvesting of fish and minding and milking of cows. Primary production is, for example, what farmers do, producing the food that is brought to the farm-gate, from where the processors take over. So the food chain runs, according to your preference for a snappy soundbite, from grass to glass (for milk), farm to fork, slurry to curry, or (taking the food chain to its logical conclusion, and including the role of the human gut charmingly but appropriately in the chain) from farm to flush. But where do these raw materials that are yielded by primary production actually come from? It is often said that all things found on earth can be divided into categories of animal, vegetable, and mineral. To these could perhaps be added two more categories, microbial and synthetic (man-made). Within these five groups can essentially be placed everything we know as food, so using this classification to consider where our food comes from seems like a good starting point for this book. Perhaps the simplest group to start with is minerals, which might intuitively seem an unlikely source of foodstuffs (do we eat metal or rock?), until we consider where salt comes from and how much of it we add to our food (in other words, probably too much). Our bodies, however, absolutely need for us to consume certain metals and other chemical elements to survive, beyond the sodium and chloride we get from salt, and so many extracted minerals find their way from deposits in the earth into food products. This is particularly important where their biological effects are a desirable outcome (such as in carefully formulated nutritional products). In addition, products such as milk contain minerals like calcium, magnesium, zinc, and more, because the infant or calf needs them to thrive.

Sign in / Sign up

Export Citation Format

Share Document