Soil Characteristics and Hydromorphological Patterns Control Denitrification at the Floodplain Scale

Nitrate pollution in aquatic ecosystems is still a major problem in Germany. There is a great potential to permanently remove nitrate from aquatic systems through denitrification as a relevant ecosystem function. However, the controlling factors and the dimension of the denitrification potential are still not fully understood due to the high complexity of the process. This study presents the combined assessment of potential soil denitrification rates, physical and chemical soil parameters, and hydrological parameters from six floodplains of four large German rivers, namely the Rhine, the Elbe, the Weser, and the Main. Based on multivariate statistics, results show that the denitrification potential of soil was almost solely controlled by soil pH. The lab assays showed mean soil denitrification potentials of 6.4–11.4 mg N m−2 h−1 (pH < 7) and 23.0–30.5 mg N m−2 h−1 (pH > 7). We contend that when upscaling these estimates to annual rates of potential denitrification, the duration of average inundation should be incorporated, as this accounts for water saturation and nutrient supply − the major controlling variables for denitrification. Results provide evidence that the denitrification potential can only be fully exploited in frequently inundated floodplains. Thus, despite favorable soil conditions for denitrification, floodplains that have suffered from anthropogenic impacts, lose their importance in nitrate removal for the river system. We conclude that pH and lateral hydrological connectivity are likely to be key factors that should be considered when estimating denitrification as an ecosystem function.

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Biochar Improves Maize Growth but Has a Limited Effect on Soil Properties: Evidence from a Three-Year Field Experiment

Sustainability ◽

10.3390/su13073617 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3617

Author(s):

Agnieszka Medyńska-Juraszek ◽

Agnieszka Latawiec ◽

Jolanta Królczyk ◽

Adam Bogacz ◽

Dorota Kawałko ◽

...

Keyword(s):

Low Temperature ◽

Field Experiment ◽

Soil Properties ◽

High Efficiency ◽

Crop Yields ◽

Temperate Climate ◽

Soil Conditions ◽

Maize Growth ◽

Chemical Soil ◽

Physical And Chemical

Biochar application is reported as a method for improving physical and chemical soil properties, with a still questionable impact on the crop yields and quality. Plant productivity can be affected by biochar properties and soil conditions. High efficiency of biochar application was reported many times for plant cultivation in tropical and arid climates; however, the knowledge of how the biochar affects soils in temperate climate zones exhibiting different properties is still limited. Therefore, a three-year-long field experiment was conducted on a loamy Haplic Luvisol, a common arable soil in Central Europe, to extend the laboratory-scale experiments on biochar effectiveness. A low-temperature pinewood biochar was applied at the rate of 50 t h−1, and maize was selected as a tested crop. Biochar application did not significantly impact the chemical soil properties and fertility of tested soil. However, biochar improved soil physical properties and water retention, reducing plant water stress during hot dry summers, and thus resulting in better maize growth and higher yields. Limited influence of the low-temperature biochar on soil properties suggests the crucial importance of biochar-production technology and biochar properties on the effectiveness and validity of its application in agriculture.

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Degraded lateritic soils cape and land uses in Birbhum district, West Bengal, India

Sociedade & Natureza ◽

10.1590/s1982-45132011000300013 ◽

2011 ◽

Vol 23 (3) ◽

pp. 545-558 ◽

Cited By ~ 7

Author(s):

V. C. Jha ◽

S. Kapat

Keyword(s):

Agricultural Land ◽

West Bengal ◽

Lateritic Soil ◽

Landscape Conservation ◽

Land Uses ◽

Key Factors ◽

Birbhum District ◽

Conservation Actions ◽

Physical And Chemical ◽

Radical Conversion

Degradation of lateritic environment as found in the south western and eastern Birbhum district can be considered as irresistible. Inherently poor physical and chemical status of existing lateritic soil profile and radical conversion of land uses as observed at cadastral level are the key factors of land degradation. Lateritic soilscapes are mostly affected by water erosion induced, vegetal and anthropogenic degradation attaining severe and very severe degradation status. Degraded lands in sample mouzas like Ballabhpur, Shyambati, Chawpahari Jungle, Bodakuri and Pachami account for 60.33%, 71.42%, 72.99%, 87.31% and 79.66% respectively out of their total lateritic exposures. In other words about 36.98%, 71.42%, 61.73%, 56.70% and 76.02% out of their total village areas and mostly non agricultural land use are affected by it. Four degraded villages get the higher priority for friendly landscape conservation actions.

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Examination of soil parameters based on the evaluation of the spectroradiometric reflectance characteristics of the topsoil

Acta Agraria Debreceniensis ◽

10.34101/actaagrar/60/2027 ◽

2014 ◽

pp. 75-80

Author(s):

Károly Bakos ◽

Attila Dobos ◽

János Nagy

Keyword(s):

Measurement Techniques ◽

Soil Surface ◽

Soil Parameters ◽

Surface Reflectance ◽

Imaging Spectrometer ◽

Top Soil ◽

Multiple Samples ◽

Physical And Chemical ◽

Landscape Formation

In this article we are presenting the methodology applied to analyse and interpret the topsoil surface reflectance parameters of multiple samples collected in the Mugello valley area in northern Italy in October 2012. The main aim of the whole project was to discover geomorphological behaviour and situation of the area ino order to improve potential for correct dating of certain archaeological artefacts found in the nearby areas. One of the crucial problem researchers are facing in the area is the lack of understanding of the underlying geological and geomorphological processes that were describing and characterizing the area and that played important role not only in the current geography and landscape formation but also in the transportation of various sediments and artefacts. In this particular research the main aim is to examine the possibility of developing a quick way to assess low level properties of the soil using hand held spectrometer and rapid analysis of cross-section using in situ measurement techniques. In this work we collected over 2000 individual samples of topsoil surface reflectance properties that we organized into a spectral library. This library is then to be used to describe physical and chemical processes in the soil. To support the analysis results were compared to analysis results from different kind of assessments in the same area. Our results show a great potential of application of hand held imaging spectrometer in soil property analysis based on the top soil surface reflectance parameters.

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Determination of Physical and Chemical Soil Parameters on Selenium Adsorption, Desorption by Rice Growing Soil

Asian Journal of Plant Sciences ◽

10.3923/ajps.2014.147.155 ◽

2014 ◽

Vol 13 (4-8) ◽

pp. 147-155

Author(s):

N. Alifar ◽

A.R. Zaharah ◽

C.F. Ishak ◽

Y. Awang ◽

B. Khayambash

Keyword(s):

Soil Parameters ◽

Chemical Soil ◽

Adsorption Desorption ◽

Physical And Chemical

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Limnological Features of Cedar Lake, Manitoba

Journal of the Fisheries Research Board of Canada ◽

10.1139/f65-101 ◽

1965 ◽

Vol 22 (5) ◽

pp. 1123-1136

Author(s):

D. W. Webb

Keyword(s):

Thermal Stratification ◽

River System ◽

Dry Weight ◽

Total Dissolved Solids ◽

Mean Value ◽

Total Alkalinity ◽

Bottom Fauna ◽

Chemical Factors ◽

Main Basin ◽

Physical And Chemical

Cedar Lake, largest lake in the Saskatchewan River system, was studied from June 14 until August 31, 1962. Twenty stations, located in the main basin of the lake, were examined during six sampling periods. These stations were located along five transects, at depths of 1.5, 3, 6, and 9 m. No thermal stratification occurred and the oxygen concentration never fell below 78% of air saturation. Total alkalinity and total dissolved solids averaged above 65 and 270 ppm, respectively.The average number of bottom organisms increased with depth, with the bulk of these being made up of spheariid clams, mayflies, chironomids, and gastropods. The number of genera also increased with depth. The standing crops determined for the six sampling periods ranged from 17.7 to 33.2 lb/acre (dry weight), with a mean value of 23.4 lb/acre. Correlations between the physical and chemical factors and the distribution of bottom fauna are examined and it is felt that the bottom type is the major factor affecting the distribution and abundance of bottom organisms in Cedar Lake. On the basis of the physical and chemical criteria, Cedar Lake may be classified as eutrophic.

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Mechanistic representation of soil nitrogen emissions in the Community Multiscale Air Quality (CMAQ) model v 5.1

Geoscientific Model Development ◽

10.5194/gmd-12-849-2019 ◽

2019 ◽

Vol 12 (2) ◽

pp. 849-878 ◽

Cited By ~ 2

Author(s):

Quazi Z. Rasool ◽

Jesse O. Bash ◽

Daniel S. Cohan

Keyword(s):

Air Quality ◽

Spatial Heterogeneity ◽

Model Performance ◽

Soil Conditions ◽

Soil Parameters ◽

N Availability ◽

Biogeochemical Processes ◽

Mineral N ◽

N Transformations ◽

No Emissions

Abstract. Soils are important sources of emissions of nitrogen-containing (N-containing) gases such as nitric oxide (NO), nitrous acid (HONO), nitrous oxide (N2O), and ammonia (NH3). However, most contemporary air quality models lack a mechanistic representation of the biogeochemical processes that form these gases. They typically use heavily parameterized equations to simulate emissions of NO independently from NH3 and do not quantify emissions of HONO or N2O. This study introduces a mechanistic, process-oriented representation of soil emissions of N species (NO, HONO, N2O, and NH3) that we have recently implemented in the Community Multiscale Air Quality (CMAQ) model. The mechanistic scheme accounts for biogeochemical processes for soil N transformations such as mineralization, volatilization, nitrification, and denitrification. The rates of these processes are influenced by soil parameters, meteorology, land use, and mineral N availability. We account for spatial heterogeneity in soil conditions and biome types by using a global dataset for soil carbon (C) and N across terrestrial ecosystems to estimate daily mineral N availability in nonagricultural soils, which was not accounted for in earlier parameterizations for soil NO. Our mechanistic scheme also uses daily year-specific fertilizer use estimates from the Environmental Policy Integrated Climate (EPIC v0509) agricultural model. A soil map with sub-grid biome definitions was used to represent conditions over the continental United States. CMAQ modeling for May and July 2011 shows improvement in model performance in simulated NO2 columns compared to Ozone Monitoring Instrument (OMI) satellite retrievals for regions where soils are the dominant source of NO emissions. We also assess how the new scheme affects model performance for NOx (NO+NO2), fine nitrate (NO3) particulate matter, and ozone observed by various ground-based monitoring networks. Soil NO emissions in the new mechanistic scheme tend to fall between the magnitudes of the previous parametric schemes and display much more spatial heterogeneity. The new mechanistic scheme also accounts for soil HONO, which had been ignored by parametric schemes.

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Heterogeneity and Anthropogenic Impacts on a Small Lowland Stream

Water ◽

10.3390/w11102002 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2002

Author(s):

Somlyai ◽

Berta ◽

Nagy ◽

Dévai ◽

Ács ◽

...

Keyword(s):

Agricultural Land ◽

Human Impacts ◽

Anthropogenic Impacts ◽

Anthropogenic Effects ◽

Nitrogen And Phosphorus ◽

Buffer Zones ◽

Small Surface ◽

Great Heterogeneity ◽

Physical And Chemical Variables ◽

Physical And Chemical

During our work, we investigated the physical and chemical variables of a small surface watercourse to investigate how different anthropogenic effects affect its water quality. Along this small watercourse, there are well-separated areas that are affected by various anthropogenic effects. In addition to its origin and branches, in many places it is surrounded by agricultural land with insufficient buffer zones, which burdens the small watercourse with nitrogen and phosphorus forms. In the lower stages, artificial damming inhibits the natural flow of the Tócó Canal, thereby creating eutrophicated stagnant water areas. This is further strengthened by, in many cases, illegal communal and used water intake that further burdens the small watercourse. Considering the experience of our investigation, it can be stated that the examined small watercourse could barely suffer human impacts, and it could be described with great heterogeneity using physical and chemical variables. We experienced that this heterogeneity caused by anthropogenic effects appeared in all hydrologic states and seasons. Furthermore, our research showed that these small watercourses had such high heterogeneity that their monitoring and examination should be taken just as seriously as when it comes to larger watercourses.

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Influence of maturity stage on fruit longevity of cherry tomatoes stored at ambient and controlled temperature

Semina Ciências Agrárias ◽

10.5433/1679-0359.2016v37n6p4027 ◽

2016 ◽

Vol 37 (6) ◽

pp. 4027

Author(s):

Cristiana Maia de Oliveira ◽

Leandro Martins Ferreira ◽

Margarida Gorete Ferreira do Carmo ◽

Regina Celi Cavestre Coneglian

Keyword(s):

Ambient Temperature ◽

Titratable Acidity ◽

Soluble Solids ◽

Maturity Stage ◽

Key Factors ◽

Maturity Stages ◽

Randomized Design ◽

Fruit Maturity ◽

Physical And Chemical ◽

Cherry Tomatoes

Fruit maturity stage has direct influence on the post-harvest life and consumer quality. Therefore, the understanding of the maturation process and its quality characteristics for storage are key factors for commercialization. In face of the foregoing, this study aimed to determine shelf life and changes in physical and chemical indexes of cherry tomatoes (Perinha Água Branca (PAB) and Mascot), assessing fruit harvested at four maturity stages and stored at ambient and controlled temperatures. For this, it was used fruit at turning, pink, red and ripe maturity stages, submitted to ambient (25 ± 2 °C) and controlled (12 °C and 90% RH) temperature, and assessed over time the indexes of fresh mass loss, titratable acidity, pH, soluble solids and ascorbic acid. The experimental design was completely randomized design in a factorial scheme of 2×4×7 for ambient temperature and 2×4×8 for controlled temperature. At ambient temperature, a longevity of up to 20 days was observed for PAB and Mascot fruit harvested at turning and pink maturity stages. When harvested at red and ripe stages, the longevity was of 15 days for PAB fruit and of 15 and 11 days, respectively, for Mascot fruit. At controlled temperature, PAB fruit showed longevity of 24 days when harvested at turning and pink stages and of 20 and 7 days, respectively, when harvested at red and ripe stages. A longevity of up to 27 days was observed for Mascot fruit harvested at turning stage and of 24 days for the other stages. The fruit harvested at turning and pink maturity stages, associated with storage under controlled conditions, presented higher longevity and maintenance of physical and chemical indexes of quality.

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The influence of termite-induced heterogeneity on savanna vegetation along a climatic gradient in West Africa

Journal of Tropical Ecology ◽

10.1017/s0266467412000703 ◽

2012 ◽

Vol 29 (1) ◽

pp. 11-23 ◽

Cited By ~ 31

Author(s):

Arne Erpenbach ◽

Markus Bernhardt-Römermann ◽

Rüdiger Wittig ◽

Adjima Thiombiano ◽

Karen Hahn

Keyword(s):

West Africa ◽

Plant Species ◽

Large Scale ◽

Regional Scale ◽

Soil Conditions ◽

Soil Parameters ◽

Climatic Gradient ◽

Termite Mound ◽

Savanna Vegetation ◽

Bioclimatic Variables

Abstract:Termites are renowned ecosystem engineers. Their mounds have been described as an important element of savanna vegetation dynamics, but little is known about their large-scale impact on vegetation composition. To investigate the influence of termite-induced heterogeneity in savannas along a climatic gradient in West Africa termite mound vegetation was compared with adjacent savanna vegetation using 256 paired plots (size of the termite mound and a corresponding savanna area) in five protected areas from northern Burkina Faso to northern Benin. On each plot vegetation and soil sampling was performed. Additionally bioclimatic variables from the WORLDCLIM database were used. The vegetation on the mounds and the surrounding savanna differed within all study sites (DCA length of gradient 3.85 SD) and showed complete turnover along the climatic gradient (DCA length of gradient 5.99 SD). Differences between mounds and savanna were significantly related to termite-induced changes in soil parameters, specifically clay enrichment and increased cation concentrations (base saturation). On a local scale, termite-induced differences in soil conditions were found to be the most important factor affecting mound vegetation, while on a regional scale, annual precipitation showed the strongest significant correlations. However, with increasing precipitation, differences between mounds and the surrounding matrix became more pronounced, and the contribution of mounds to local phytodiversity increased. Eleven plant species were identified as characteristic termite mound species. In the more humid parts of the gradient, more characteristic plant species were found that may benefit from favourable soil conditions, good water availability, and a low fire impact in the mound microhabitat.

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Microplastics: Are they really a threat to groundwater systems?

10.5194/egusphere-egu2020-9069 ◽

2020 ◽

Author(s):

Ahmad Ameen ◽

Margaret Stevenson ◽

Alfred Paul Blaschke

Keyword(s):

Land Surface ◽

United Nations Environment Programme ◽

Natural Environments ◽

Key Factors ◽

Ongoing Research ◽

Chemical Mechanisms ◽

Emerging Pollutant ◽

Groundwater Systems ◽

Transport Behaviour ◽

Physical And Chemical

Recently, global annual plastics production has reached a record of 359 million tonnes and in Europe nearly 62 million tonnes, with only a small portion (6-26%) being recycled. Plastic debris released into the environment are categorized, according to size, as macroplastics (> 5mm), microplastics (0.1&#956;m - 5mm) and nanoplastics (< 0.1&#956;m). Microplastics are now recognized as an emerging pollutant due to their abundance in natural environments, and because of growing concerns, the United Nations Environment Programme (UNEP) has included it in the list of top 10 environmental problems.Additionally, microplastics have a tendency to act as a vector for other contaminants such as pathogens, organic pollutants and heavy metals due to strong dispersion and diffusion mechanisms. The majority of ongoing research on microplastics has primarily focussed on marine systems, but land surface contamination may also be important due to observed release rates that are approximately 20 times higher, in comparison to oceans. Nevertheless, only a few studies have addressed the presence of microplastics in soil and groundwater.A research gap exists regarding the physical and chemical mechanisms that govern microplastic transport and retention in groundwater. Therefore, a study is being conducted to investigate the distribution, fate and transport of microplastics through groundwater. The overall aim is to improve the understanding of the transport mechanisms of these emerging pollutants and if they enhance the mobility of microbial communities. This research has two main objectives: firstly, to simulate the transport behaviour of various kinds of microplastics (different types, shapes, sizes, and surface morphology), secondly, to analyse the microplastics as potential vectors for microorganisms.The key factors that are affecting the transport of different sized microplastics will be addressed. Additionally, the co-transport of microorganisms with microplastics during their movement within soil and groundwater will also be considered.

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