scholarly journals The effect of crop coverage on the daily dynamism of the soil’s CO2 emission

2010 ◽  
pp. 97-102
Author(s):  
Nikolett Szőllősi ◽  
Csaba Juhász ◽  
Györgyi Kovács ◽  
József Zsembeli
Keyword(s):  
Greenhouse Gases ◽  
Co2 Emission ◽  
Soil Surface ◽  
Bare Soil ◽  
Organic Content ◽  
Total Carbon ◽  
Large Area ◽  
Total Carbon Content ◽  
Ecosystem Research ◽  
Global Carbon

Nowadays one of main goals of international ecosystem research the measurement of greenhouse gases (CO2, N2O and CH4) in different places. The fluctuation of these greenhouse gases – quantity and trend in the case of CO2 and CH4 – could be diverse with atmosphere because it depends on several effects of factors like climate, soil type, vegetation. In grassland out of the three greenhouse gases which fill a part in gas emission, in the case of CO2 soil and vegetation are the most important factors (Soussana et al., 2007).In the aspect of global carbon balance grasslands are very important by their large area extension, total carbon content, organic content store (10% of the global carbon storage) (Lemmens et al., 2006). In this summer measurements were carried out to determine CO2 emission of the soil from different soil surfaces like grass covered and bare soil surface during a whole day.

scholarly journals Sight-specific development of the tools for the measurement of CO2-emission of the soil

2008 ◽  
pp. 53-58
Author(s):  
Györgyi Kovács ◽  
Nikolett Szőllősi
Keyword(s):  
Greenhouse Gases ◽  
Co2 Emission ◽  
Soil Surface ◽  
Soil Tillage ◽  
Crop Fields ◽  
New Instrument ◽  
Metal Frame ◽  
Infrared Gas Analyser ◽  
Measurement Area

Soil is the main source and at the same time the potential sink of greenhouse gases (e.g. CO2, CH4). Measurements were carried out in the experimental sites (soil tillage experiments and an extensive pasture) of the Karcag Research Institute of University of Debrecen, Centre for Agricultural Sciences to determine the CO2-emission of the soil. The in situ CO2-emission of soil was measured by means of an ANAGAS 98 infrared gas analyser in plastic (PVC) chambers, but this previously applied method (cylinders) was not suitable for the soil surface covered with grass,hence a new instrument was needed to be invented. In order to measure CO2-emission on a larger area without deep disturbance of the soil, a special metal frame was created with a matching bowl. The most problematic part was the spatial delimitation of the measurement area as the surface of the soil can be very various and proper isolation is a must. We consider the frame+bowl method we developed suitable for measuring CO2-emission of pastures as well as other crop-fields. 

Runoff and micromorphological properties of a grazed haplargid, near Cobar, NSW, Australia

Soil Research ◽  
1998 ◽  
Vol 36 (1) ◽  
pp. 87 ◽  
Author(s):  
R. S. B. Greene ◽  
W. D. Nettleton ◽  
C. J. Chartres ◽  
J. F. Leys ◽  
R. B. Cunningham
Keyword(s):  
High Intensity ◽  
Surface Soil ◽  
Soil Surface ◽  
Perennial Grasses ◽  
Total Carbon ◽  
Total Carbon Content ◽  
Land System ◽  
Goat Grazing ◽  
Intensity Grazing ◽  
Very High

We investigated the effects of 2 different grazing regimes on the surface soil properties of a dunefield land system in the semi-arid woodlands of eastern Australia. Sandy siliceous, thermic Xeric Haplargids (Siliceous Sands, Uc1·23) occur on the sandy, 2–4-m-high longitudinal dunes. Fine-loamy, siliceous, thermic Xeric Haplargids (Massive Red Earths, Uc2·13) occur in the swales between the dunes. We compared very high-intensity grazing (approx. 1 year) by feral goats with low-intensity grazing (approx. 4 years) by sheep. A rainfall simulator, applying water at the rate of 30 mm/h, measured the hydraulic properties of the surface soils formed under the 2 different grazing regimes. We examined undisturbed samples of the upper 5-cm layer of the soil surface using micromorphological techniques. In the swales, there were no differences in the effects of the 2 grazing regimes on soil properties. At low-intensity sheep grazing (0·2–0·3 sheep/ha), the soil surface on the dunes remained in an excellent condition. The surface had a good vegetative cover and consisted of either loosely packed sand grains, or areas where the sand grains were bonded together by clay and organic matter to form an organic crust. The total carbon content of the 0–2 cm depth of soil was 0·86%. Both soil surfaces have a high infiltration rate (i.e. >30 mm/h) and also appear to contain stable microaggregates of parna material distributed among the eolian sand grains. Very high-intensity goat grazing (up to 4·0 goats/ha) rapidly depleted the perennial grasses, killed most of the shrubs, and converted the soil surface on the dunes to one highly susceptible to erosion by wind. The low total carbon content (depth 0–2 cm) of 0·3% and absence of iron-stained clay coatings on the sands further support this view. The surface soil on the dunes in the very high-intensity goat-grazing plots consisted of either loosely packed sand grains or areas where poorly orientated clays coated the sand grains to form a strong, physical crust. We suggest that the physical crust may cause a change in the hydrology of the land system which may enhance the conditions for recruitment of unpalatable shrubs in the dune–swale interface. This increase in unpalatable shrubs and decrease in perennial grasses caused by the very high intensity goat grazing is therefore detrimental to the long-term productivity of these semi-arid lands.

Morphologic and Engineering Characteristics of East Wasit Watersheds Feeding the Al-Shewicha Trough in Iraq

2020 ◽  
Vol 55 (1) ◽  
Author(s):  
Mohammed S. Shamkhi ◽  
Jasim Mohammed Ridha Azee ◽  
Ali A. Abdul-Sahib
Keyword(s):  
Peak Flow ◽  
Flood Hazard ◽  
Bare Soil ◽  
Elongation Ratio ◽  
High Concentration ◽  
Large Area ◽  
Coarse Texture ◽  
Loam Soil ◽  
High Runoff ◽  
Group B

The Al-Shewicha Trough represents a serious flood hazard to Kut City (the capital of Wasit Province, Iraq) and to the other cities along the Tigris River downstream Kut Barrage, especially in heavy monsoon years. In this study, The Geographic Information System software ArcGIS was used in the morphologic analysis of six river basins that represent the main feeding sources for the Al-Shewicha Trough. The results revealed that the high values for the greatest length of Basins 1, 5, and 6 meant that these watersheds had high concentration time (tc) values, which delay peak flow. All basins consisted of very coarse and permeable subsurface strata that were of coarse texture. Circularity ratio form factor and elongation ratio suggested an elongated shape for all basins with lower peak flow and long duration. Analyses of soil data demonstrated that the soil type that covered a large area was loam soil (classified as hydrologic soil group B), which indicates that all basins had low permeability and high runoff. The predominant land use was bare soil, and all basins had a covering of poor vegetation, which highlighted the fact that basins were highly susceptible to erosion, thus resulting in the generation of higher sedimentation.

Transport of soluble organic and inorganic carbon in sandy soils under nitrogen fertilization

1999 ◽  
Vol 79 (2) ◽  
pp. 303-310 ◽  
Author(s):  
F. L. Wang ◽  
A. K. Alva
Keyword(s):  
Nitrogen Fertilization ◽  
Inorganic Carbon ◽  
Average Rate ◽  
Sandy Soils ◽  
Water Soluble ◽  
Total Carbon ◽  
Total Carbon Content ◽  
Water Soluble Organic Carbon ◽  
Isobutylidene Diurea ◽  
Leaching Condition

Leaching of water soluble soil carbon plays an important role in downward transport of soil nutrients and pollutants and may be influenced by soil and management factors. We examined the leaching of water soluble carbon from two sandy soils under nitrogen fertilization by adapting an intermittent leaching-incubation technique using packed soil columns (94 × 10 cm). After 30 d, cumulative amounts of water-soluble organic carbon (SOC) leached from the Candler and Wabasso sand for various treatments in mg C column−1 were: 77 and 302 (NH4NO3), 64 and 265 (control), and 45 and 239 (isobutylidene diurea, IBDU), respectively. The IBDU and NH4NO3 treatments increased the leaching of water-soluble inorganic carbon (SIC), which ranged from 2 to 38 mg C column−1 over 30 d. At the end of eight cycles of leaching/incubation, the total carbon content increased at depth (control and NH4NO3 treatment) in the Candler sand, but decreased in the Wabasso sand. In the first leaching event, the average rate of SOC leaching from the Wabasso sand was 26 mg C column−1 d−1 which dropped rapidly to about 5 mg C column−1 d−1 towards the end of the experiment. The rate of SOC leaching from the Candler sand was much lower (<8 mg C column−1 d−1) than the rate of SOC leaching from the Wabasso sand. Compared with the unamended treatments, application of NH4NO3 increased and IBDU decreased the leaching of SOC in both soils. These effects of N application were considerable during the initial two to three leaching events only. Our results suggest that the initial rainfalls that follow a dry period may be critical for transporting SOC from the upper layer of these sandy soils. Key words: C leaching, sandy soil, intermittent leaching condition, isobutylidene

scholarly journals Characteristics of Liparis loeselii (L.) Rich. populations in selected Natura 2000 areas in eastern Poland

2020 ◽  
Vol 55 (3) ◽  
pp. 151-162
Author(s):  
Danuta Urban ◽  
Joanna Sender ◽  
Ewelina Tokarz ◽  
Andrzej Różycki
Keyword(s):  
Natura 2000 ◽  
Total Carbon ◽  
Habitat Conditions ◽  
Total Carbon Content ◽  
Poor Fen ◽  
Calcareous Fen ◽  
Liparis Loeselii ◽  
The Individual ◽  
Insight Into

AbstractIn view of the sensitivity of Liparis loeselii to changes in habitat conditions, we carried out a study with the aim to monitor population numbers, identify the individual features of the Liparis loeselii population, analyse habitat conditions, identify threats and propose conservation measures to preserve the species. The investigations were conducted in seven unmanaged objects located in three Natura 2000 areas in eastern Poland. The results of this study provide a new insight into Liparis loeselii ecology. The analysed populations inhabited some habitat types: extremely poor fen, transitional mire, rich fen, calcareous fen, spring-fed fen. The content of nutrients was similar in all the habitats. A CCA analysis revealed that the total carbon content, pH, and redox potential of the substrate determine differences between the habitats analysed. Juvenile individuals represented a maximum of 12% of the analysed populations and were the least abundant group of these plants. The flowering was primarily influenced by hydrological conditions. Based on the long-term observations reported in this article, it can be assumed that the species stands a chance of surviving at the localities analysed, provided that the habitat conditions do not change dramatically.

scholarly journals Archaeal ammonia oxidizers respond to soil factors at smaller spatial scales than the overall archaeal community does in a high Arctic polar oasis

2016 ◽  
Vol 62 (6) ◽  
pp. 485-491 ◽  
Author(s):  
Samiran Banerjee ◽  
Nabla Kennedy ◽  
Alan E. Richardson ◽  
Keith N. Egger ◽  
Steven D. Siciliano
Keyword(s):  
Community Structure ◽  
Spatial Scales ◽  
Archaeal Community ◽  
Diversity Indices ◽  
High Arctic ◽  
Total Carbon ◽  
Spatial Dependency ◽  
Edaphic Factors ◽  
Total Carbon Content ◽  
Arctic Soils

Archaea are ubiquitous and highly abundant in Arctic soils. Because of their oligotrophic nature, archaea play an important role in biogeochemical processes in nutrient-limited Arctic soils. With the existing knowledge of high archaeal abundance and functional potential in Arctic soils, this study employed terminal restriction fragment length polymorphism (t-RFLP) profiling and geostatistical analysis to explore spatial dependency and edaphic determinants of the overall archaeal (ARC) and ammonia-oxidizing archaeal (AOA) communities in a high Arctic polar oasis soil. ARC communities were spatially dependent at the 2–5 m scale (P < 0.05), whereas AOA communities were dependent at the ∼1 m scale (P < 0.0001). Soil moisture, pH, and total carbon content were key edaphic factors driving both the ARC and AOA community structure. However, AOA evenness had simultaneous correlations with dissolved organic nitrogen and mineral nitrogen, indicating a possible niche differentiation for AOA in which dry mineral and wet organic soil microsites support different AOA genotypes. Richness, evenness, and diversity indices of both ARC and AOA communities showed high spatial dependency along the landscape and resembled scaling of edaphic factors. The spatial link between archaeal community structure and soil resources found in this study has implications for predictive understanding of archaea-driven processes in polar oases.

EFFECT OF CANOPY AND INCORPORATION ON METRIBUZIN PERSISTENCE IN SOILS

1989 ◽  
Vol 69 (3) ◽  
pp. 711-714 ◽  
Author(s):  
K. I. N. JENSEN ◽  
E. R. KIMBALL ◽  
J. A. IVANY
Keyword(s):  
Key Words ◽  
Half Life ◽  
Field Tests ◽  
Soil Surface ◽  
Bare Soil ◽  
Field Conditions ◽  
Row Width ◽  
Sampling Zone

The half-life of metribuzin applied to a bare soil surface was calculated to be 3–7 d over four field tests. An artificial cover erected after application or a shallow incorporation increased the half-life of metribuzin approximately 2.5- to 3-fold. Leaching out of the 0- to 5-cm-deep sampling zone could not account for loss of metribuzin. It was concluded that metribuzin persistence may be affected by volatility and/or photodecomposition losses under field conditions, especially shortly after application. Key words: Metribuzin half-life, volatility, photodecomposition, row width

Performance of intermittent aeration reactor on NH4-N removal from groundwater resources

2010 ◽  
Vol 61 (12) ◽  
pp. 3061-3069 ◽  
Author(s):  
W. Khanitchaidecha ◽  
T. Nakamura ◽  
T. Sumino ◽  
F. Kazama
Keyword(s):  
Removal Rate ◽  
Groundwater Resources ◽  
Ammonium Nitrogen ◽  
Total Carbon ◽  
Intermittent Aeration ◽  
Reactor Performance ◽  
Total Carbon Content ◽  
Term Operation ◽  
N Removal ◽  
Synthetic Groundwater

To study the effect of intermittent aeration period on ammonium–nitrogen (NH4-N) removal from groundwater resources, synthetic groundwater was prepared and three reactors were operated under different conditions – “reactor A” under continuous aeration, “reactor B” under 6 h intermittent aeration, and “reactor C” under 2 h intermittent aeration. To facilitate denitrification simultaneously with nitrification, “acetate” was added as an external carbon source with step-wise increase from 0.5 to 1.5 C/N ratio, where C stands for total carbon content in the system, and N for NH4-N concentration in the synthetic groundwater. Results show that complete NH4-N removal was obtained in “reactor B” and “reactor C” at 1.3 and 1.5 C/N ratio respectively; and partial NH4-N removal in “reactor A”. These results suggest that intermittent aeration at longer interval could enhance the reactor performance on NH4-N removal in terms of efficiency and low external carbon requirement. Because of consumption of internal carbon by the process, less amount of external carbon is required. Further increase in carbon in a form of acetate (1.5 to 2.5 C/N ratios) increases removal rate (represented by reaction rate coefficient (k) of kinetic equation) as well as occurrence of free cells. It suggests that the operating condition at reactor B with 1.3 C/N ratio is more appropriate for long-term operation at a pilot-scale.

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