RATES OF CALCIUM CARBONATE REMOVAL FROM SOILS

1988 ◽  
Vol 68 (2) ◽  
pp. 449-454 ◽  
Author(s):  
N. VAN BREEMEN ◽  
R. PROTZ
Keyword(s):  
Calcium Carbonate ◽  
Calcareous Soils ◽  
Water Drainage ◽  
Carbonate Weathering ◽  
Soil Chronosequence ◽  
Drainage Rate ◽  
Wide Range ◽  
Subarctic Climate ◽  
Equilibrium Concentrations ◽  
Study Sites

Mean annual rates of calcium carbonate removal from soils in a subarctic climate estimated from data on two chronosequences of calcareous storm ridges, appeared to be relatively constant through time. Concentrations of dissolved calcium carbonate in the soil solution in the study sites calculated from the rates of weathering of CaCO3 and of water drainage are in the range expected for equilibrium with calcite. The same conclusion could be drawn from published studies elsewhere. Over a wide range of conditions, the dissolution rate of calcite appears to be high enough to maintain equilibrium concentrations in water percolating calcareous soils and rocks. Consequently, the rate of calcium carbonate weathering can be predicted from (1) the solubility of CaCO3 and (2) the water drainage rate. Key words: Calcium carbonate weathering, soil chronosequence, subarctic soils

Geographic Variation in Habitat Structure of the Black-Throated Green Warbler (Dendroica virens)

The Auk ◽  
1983 ◽  
Vol 100 (2) ◽  
pp. 382-389 ◽  
Author(s):  
Scott L. Collins
Keyword(s):  
New York ◽  
Plant Community ◽  
Habitat Structure ◽  
Habitat Management ◽  
Principal Component ◽  
Structural Features ◽  
Wide Range ◽  
White Mountain National Forest ◽  
Study Sites ◽  
Regional Analyses

Abstract Habitat structure of the Black-throated Green Warbler (Dendroica virens) was examined at five study sites: (1) Mount Desert Island, Maine; (2) Mount Blue State Park, Maine; (3) White Mountain National Forest, New Hampshire; (4) southern Adirondacks, New York; and (5) Itasca State Park, Minnesota. Principal component analysis of 13 habitat-structure variables measured at each site produced habitat gradients from tall to shorter canopies, large to smaller trees, and coniferous to deciduous forests. A second ordination indicated that the habitat sampled included five plant-community types: pine forests, spruce-arbor vitae, balsam fir, mixed spruce-fir-deciduous, and beech-maple-birch. Consistent structural features within the total range of habitats sampled were difficult to identify. I suggest that widely occurring species such as the Black-throated Green Warbler have a wide range of habitats with a suitable structure and that regional analyses, even within a single plant-community type, may be of limited value with regard to habitat management when considering the entire range of many species.

scholarly journals Stand Characteristics and Productivity Potential of Indiana Surface Mines Reclaimed Under SMCRA

2006 ◽  
Vol 23 (2) ◽  
pp. 94-99 ◽  
Author(s):  
John W. Groninger ◽  
Stephen D. Fillmore ◽  
Ron A. Rathfon
Keyword(s):  
Forest Cover ◽  
Robinia Pseudoacacia ◽  
Surface Mining ◽  
Forest Productivity ◽  
Site Index ◽  
Green Ash ◽  
Surface Mines ◽  
Wide Range ◽  
Study Sites ◽  
Productivity Potential

Abstract The Surface Mining Control and Reclamation Act of 1977 (SMCRA) addresses a wide range of environmental concerns. However, its impacts on forest stand development and productive potential have only recently been investigated. We surveyed the vegetation and forest productivity on 22 surfacemine sites throughout the coal-bearing region of Indiana that were reclaimed to forest cover under the provisions of SMCRA 7–14 years prior to sampling. Black locust (Robinia pseudoacacia) and green ash (Fraxinus pennsylvanica) were the most widely occurring tree species.Tall fescue and goldenrod were the most widely occurring nonarborescent species. Median site index (base age 50 for black oak) was 30 ft. Although satisfying forest cover stocking requirements for bond release, these reclaimed surface mines almost always displayed a level of productivity farbelow those of native forests typical of this region. Reclamation techniques differing from those used on these study sites are needed to restore forest productivity to surface-mined lands while still complying with SMCRA.

SOLUBILITY OF CALCIUM CARBONATE IN CALCAREOUS SOILS

Soil Science ◽  
1959 ◽  
Vol 88 (3) ◽  
pp. 123-129 ◽  
Author(s):  
STERLING R. OLSEN ◽  
FRANK S. WATANABE
Keyword(s):  
Calcium Carbonate ◽  
Calcareous Soils

scholarly journals Remote sensing of ecosystem light use efficiency with MODIS-based PRI

2011 ◽  
Vol 8 (1) ◽  
pp. 189-202 ◽  
Author(s):  
A. Goerner ◽  
M. Reichstein ◽  
E. Tomelleri ◽  
N. Hanan ◽  
S. Rambal ◽  
...  
Keyword(s):  
Meteorological Data ◽  
Vapour Pressure Deficit ◽  
Ground Truth ◽  
Light Use Efficiency ◽  
Wide Range ◽  
Evaluation Exercise ◽  
Use Efficiency ◽  
Study Sites ◽  
Absorbed Photosynthetically Active Radiation

Abstract. Several studies sustained the possibility that a photochemical reflectance index (PRI) directly obtained from satellite data can be used as a proxy for ecosystem light use efficiency (LUE) in diagnostic models of gross primary productivity. This modelling approach would avoid the complications that are involved in using meteorological data as constraints for a fixed maximum LUE. However, no unifying model predicting LUE across climate zones and time based on MODIS PRI has been published to date. In this study, we evaluate the effectiveness with which MODIS-based PRI can be used to estimate ecosystem light use efficiency at study sites of different plant functional types and vegetation densities. Our objective is to examine if known limitations such as dependence on viewing and illumination geometry can be overcome and a single PRI-based model of LUE (i.e. based on the same reference band) can be applied under a wide range of conditions. Furthermore, we were interested in the effect of using different faPAR (fraction of absorbed photosynthetically active radiation) products on the in-situ LUE used as ground truth and thus on the whole evaluation exercise. We found that estimating LUE at site-level based on PRI reduces uncertainty compared to the approaches relying on a maximum LUE reduced by minimum temperature and vapour pressure deficit. Despite the advantages of using PRI to estimate LUE at site-level, we could not establish an universally applicable light use efficiency model based on MODIS PRI. Models that were optimised for a pool of data from several sites did not perform well.

Relationship between soil composition and retention capacity of terbumeton onto chalky soils

2009 ◽  
Vol 6 (3) ◽  
pp. 245 ◽  
Author(s):  
Achouak El Arfaoui ◽  
Stéphanie Sayen ◽  
Eric Marceau ◽  
Lorenzo Stievano ◽  
Emmanuel Guillon ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Properties ◽  
Environmental Fate ◽  
Organic Matter Content ◽  
Calcareous Soils ◽  
Matter Content ◽  
Soil Composition ◽  
Retention Capacity ◽  
Wide Range ◽  
Soil Components

Environmental context. The wide use of pesticides for pest and weed control contributes to their presence in underground and surface waters, which has led to a continuously growing interest in their environmental fate. Soils play a key role in the transfer of these compounds from the sprayer to the water as a result of their capacity to retain pesticides depending on the soil components. The knowledge of soil composition should enable one to predict pesticide behaviour in the environment. Abstract. Eight calcareous soils of Champagne vineyards (France) were studied to investigate the adsorption of the herbicide terbumeton (TER). A preliminary characterisation of the soil samples using X-ray diffraction (XRD), elemental and textural analyses, revealed a wide range of soil properties for the selected samples. The adsorption isotherms of TER were plotted for all samples. The determination of soil properties, which significantly correlated with the Kd distribution coefficient, allowed identification of organic matter and CaCO3 as the two main soil components that govern the retention of the herbicide. Organic matter was the predominant phase involved in the retention but its role was limited by the presence of calcite. Finally, the ratio of CaCO3 content to organic matter content was proposed as a useful parameter to predict the adsorption of terbumeton in chalky soils. The evolution of Kd as a function of this ratio was successfully described using an empirical model.

scholarly journals Distribution and Habitat Preference of Hispid Hare (Caprolagus Hispidus) In Shuklaphanta National Park, Nepal

2017 ◽  
Vol 31 (1-2) ◽  
pp. 1-16
Author(s):  
Dhirendra Bahadur Chand ◽  
Laxman Khanal ◽  
Mukesh Kumar Chalise
Keyword(s):  
Population Density ◽  
National Park ◽  
Imperata Cylindrica ◽  
Grass Species ◽  
Population Status ◽  
Tall Grass ◽  
The Past ◽  
Wide Range ◽  
Food Species ◽  
Study Sites

 Hispid hare (Caprolagu shispidus) is an endangered lagomorph which had a wide range of distribution in the past, but currently it is known to occur only from few isolated tall grass pockets of India and Nepal. We explored the population status, habitat utilization and existing threats of the Hispid hare at Shuklaphanta National Park (SNP) by the strip transect and quadrate sampling methods from November 2015 to May 2016 covering both winter and summer seasons. Four study sites of total 1.58ha were selected within SNPand strip transects were randomly laid to determine presence and absence of pellets of Hispid hare and their counts were used to estimate the population density. The Population density of Hispid hare was found to be 0.1820/ha in winter and 0.2268/ha in summer with the statistically significant preference to the tall grassland habitat. Twelve grass species were identified in the habitat of Hispid hare with dominancy of Saccharum spontaneum, Imperata cylindrica, Narenga porphyrocoma, and Saccharum munj. Among the grasses, Imperata cylindrica and Narenga porphyrocoma were the food species of higher preference for Hispid hare.

scholarly journals Drainage of high-consistency fiber-laden aqueous foams

Cellulose ◽  
2020 ◽  
Vol 27 (16) ◽  
pp. 9637-9652
Author(s):  
Antti I. Koponen ◽  
Oleg Timofeev ◽  
Ari Jäsberg ◽  
Harri Kiiskinen
Keyword(s):  
Fibrous Materials ◽  
Water Drainage ◽  
Mechanical Pressure ◽  
Moisture Profile ◽  
Systematic Analysis ◽  
Drainage Rate ◽  
High Uniformity ◽  
Thermal Drying ◽  
High Consistency ◽  
Foam Forming

AbstractLightweight lignocellulosic fibrous materials (LLFMs) offer a sustainable and biodegradable alternative in many applications. Enthusiastic interest in these materials has recently grown together with the newly risen interest in foam forming. Foam bubbles restrain fiber flocculation, and foam formed structures have high uniformity. Moreover, the bubbles support the fibrous structure during manufacturing enabling the formation of highly porous structures. Mechanical pressure cannot be applied in the manufacture of LLFMs as the materials would lose their porous structure. Water is therefore typically removed by a combination of drainage and thermal drying. Thermal drying of porous materials has been studied intensively. However, there are only a few studies on the drainage of fiber-laden foams. Thus, in this work, we conducted a systematic analysis of this topic. Our findings show that after drainage a stationary vertical moisture profile similar to that of pure foams is developed. Raising the initial fiber consistency was found to increase the final fiber consistency of the foam until the drainage ceased. Increasing mold height was found to increase the final consistency considerably. Without vacuum and heating, the shrinkage of samples during drainage was only slightly higher than the volume of the drained water. Drainage rate and final consistency increased clearly with increasing vacuum, but simultaneously sample shrinkage increased considerably. The best compromise was obtained with a vacuum of 0.5 kPa, which increased the final consistency by 60% without extra shrinkage. Using warm foam and heating the foam during drainage increased the final consistency considerably, but this also led to significant shrinkage of the sample.

scholarly journals Apex structures enhance water drainage on leaves

2020 ◽  
Vol 117 (4) ◽  
pp. 1890-1894 ◽  
Author(s):  
Ting Wang ◽  
Yifan Si ◽  
Haoyu Dai ◽  
Chuxin Li ◽  
Can Gao ◽  
...  
Keyword(s):  
Leaf Surface ◽  
Control Mechanisms ◽  
Water Drainage ◽  
Tropical Plants ◽  
Leaf Apex ◽  
Drainage Rate ◽  
Retention Volumes ◽  
Rapid Removal ◽  
Shape Changes ◽  
Surface Changes

The rapid removal of rain droplets at the leaf apex is critical for leaves to avoid damage under rainfall conditions, but the general water drainage principle remains unclear. We demonstrate that the apex structure enhances water drainage on the leaf by employing a curvature-controlled mechanism that is based on shaping a balance between reduced capillarity and enhanced gravity components. The leaf apex shape changes from round to triangle to acuminate, and the leaf surface changes from flat to bent, resulting in the increase of the water drainage rate, high-dripping frequencies, and the reduction of retention volumes. For wet tropical plants, such as Alocasia macrorrhiza, Gaussian curvature reconfiguration at the drip tip leads to the capillarity transition from resistance to actuation, further enhancing water drainage to the largest degree possible. The phenomenon is distinct from the widely researched liquid motion control mechanisms, and it offers a specific parametric approach that can be applied to achieve the desired fluidic behavior in a well-controlled way.

scholarly journals Monitoring Cropping Systems: From Data Collection to Cloud Database Storage Using Open Source Software

Proceedings ◽  
2020 ◽  
Vol 30 (1) ◽  
pp. 79
Author(s):  
Ioanna Panagea ◽  
Dangol Anuja ◽  
Marc Olijslagers ◽  
Jan Diels ◽  
Guido Wyseure
Keyword(s):  
Open Source ◽  
Open Source Software ◽  
Web Application ◽  
Cropping Systems ◽  
Cropping System ◽  
Query Languages ◽  
Climatic Conditions ◽  
Raw Data ◽  
Wide Range ◽  
Study Sites

Agricultural cropping systems and experiments include complex interactions of processes and various management practices and/or treatments under a wide range of environmental and climatic conditions. The use of standardized formats to monitor and document these systems and experiments can help researchers and stakeholders to efficiently exchange data, promote interdisciplinary collaborations, and simplify modelling and analysis procedures. In the scope of the SoilCare Horizon 2020 project monitoring and assessment work package, an integrated scheme to collect, validate, store, and access cropping system information and experimental data from 16 study sites, was created. The aim of the scheme is to make the data readily available in a way that the information is useful, easy to access and download, and safe, relying only on open source software. The database design considers data and metadata required to properly and easily monitor, process, and analyse cropping systems and/or agricultural experiments. The scheme allows for the storage of data and metadata regarding the experimental set-up, associated people and institutions, information about field management operations and experimental procedures which are clearly separated for making analysis procedures faster, links between system components, and information about the environmental and climatic conditions. Raw data are entered by the users into a structured spreadsheet. The quality is checked before storing the data into the database. Providing raw data allows processing and analysing as each other user needs. A desktop import application has been created to upload the information from spreadsheet to database, which includes automated error checks of relationship tables, data types, data constraints, etc. The final component of the scheme is the database web application interface, which enables users to access and query the database across the study sites without the knowledge of query languages and to download the required data. For this system design, PostgreSQL is used for storing the data, pgAdmin 4 for database management administration, MongoDB for user management and authentication, Python for the development of the import application, Angular and Node.js/Express for the web application and spreadsheets compatible with LibreOffice Calc. The system is currently tested with data provided by the SoilCare study sites. Preliminary testing indicated that extended quality control of the spreadsheets was required from the system’s administrator to meet the standards and restrictions of the import application. Initial comments from the users indicate that the database scheme, even if it initially seems complicated, includes all the variables and details required for a complete monitoring and modelling of an agricultural cropping system.

scholarly journals Bacillus subtilis Gene Cluster Involved in Calcium Carbonate Biomineralization

2006 ◽  
Vol 189 (1) ◽  
pp. 228-235 ◽  
Author(s):  
Chiara Barabesi ◽  
Alessandro Galizzi ◽  
Giorgio Mastromei ◽  
Mila Rossi ◽  
Elena Tamburini ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Fatty Acid ◽  
Calcium Carbonate ◽  
Fatty Acid Metabolism ◽  
Insertional Mutagenesis ◽  
Molecular Mechanisms ◽  
Acid Metabolism ◽  
Precipitation Process ◽  
Calcium Carbonate Precipitation ◽  
Wide Range

ABSTRACT Calcium carbonate precipitation, a widespread phenomenon among bacteria, has been investigated due to its wide range of scientific and technological implications. Nevertheless, little is known of the molecular mechanisms by which bacteria foster calcium carbonate mineralization. In our laboratory, we are studying calcite formation by Bacillus subtilis, in order to identify genes involved in the biomineralization process. A previous screening of UV mutants and of more than one thousand mutants obtained from the European B. subtilis Functional Analysis project allowed us to isolate strains altered in the precipitation phenotype. Starting from these results, we focused our attention on a cluster of five genes (lcfA, ysiA, ysiB, etfB, and etfA) called the lcfA operon. By insertional mutagenesis, mutant strains carrying each of the five genes were produced. All of them, with the exception of the strain carrying the mutated lcfA operon, were unable to form calcite crystals. By placing transcription under IPTG (isopropyl-β-d-thiogalactopyranoside) control, the last gene, etfA, was identified as essential for the precipitation process. To verify cotranscription in the lcfA operon, reverse transcription-PCR experiments were performed and overlapping retrocotranscripts were found comprising three adjacent genes. The genes have putative functions linked to fatty acid metabolism. A link between calcium precipitation and fatty acid metabolism is suggested.

Sign in / Sign up

Export Citation Format

Share Document