scholarly journals Time for non-illuvial Bt horizons?

2021 ◽  
Author(s):  
Dan Pennock ◽  
Kendra Fisher
Keyword(s):  
Particle Size ◽  
Regional Scale ◽  
Regional Analysis ◽  
Soil Classification ◽  
Northern Forest ◽  
Forest Reserves ◽  
Texture Contrast ◽  
Soil Surveys ◽  
Diagnostic Horizon ◽  
Bt Horizon

The Bt horizon is the diagnostic horizon of the Luvisolic Order in Canada. According to the Canadian System of Soil Classification (CSSC), the Bt must be formed from clay illuviation through the processes of lessivage (i.e., physical transport of clay). In a study of a Luvisol catena in the central Saskatchewan, we demonstrate that Ae/Bm horizons overlying IIBt horizons are formed in a sandy mantle overlying till (i.e., a lithological discontinuity) and that the sandy mantle contributed negligible amounts of illuvial clay despite the presence of clay skins on ped surfaces in the IIBt horizon. We extended the results of this study to the regional scale by examining sand fractions in 63 pedons of Luvisol-dominated soil associations from soil surveys in the Northern Forest Reserves (between latitudes 53<sup>o</sup>N and 55<sup>o</sup>N). Of the 63 pedons, 13 had lithological discontinuities identified in their profile description and a further 27 had discontinuities identified through shifts in the sand fractions between horizons. For the profiles with discontinuities, inherited particle size differences are a more likely cause of coarse-over-fine textural contrasts than lessivage. A regional analysis of the distribution of Luvisol-dominated associations showed distinct zonations that account, in part, for the differences in the occurrence of lithological discontinuities. Based on these results, we suggest that the criteria for Bt horizons in the CSSC should be broadened to include non-illuvial coarse-over-fine texture-contrast horizons and that the criteria for the Luvisolic order also be broadened to include these non-illuvial Bt horizons.

Relationships between field texture and particle-size distribution in Australia and their implications

Soil Research ◽  
2007 ◽  
Vol 45 (6) ◽  
pp. 428 ◽  
Author(s):  
Budiman Minasny ◽  
Alex B. McBratney ◽  
Damien J. Field ◽  
Grant Tranter ◽  
Neil J. McKenzie ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Classification System ◽  
Soil Classification ◽  
Particle Size Analysis ◽  
Pedotransfer Functions ◽  
Size Analysis ◽  
Texture Contrast ◽  
Australian Soil

This paper aims to establish the means and ranges of clay, silt, and sand contents from field texture classes, and to investigate the differences in the field texture classes and texture determined from particle-size analysis. The results of this paper have 2 practical applications: (1) to estimate the particle size distribution and its uncertainty from field texture as input to pedotransfer functions, and (2) to examine the criteria of texture contrast soils in the Australian Soil Classification system. Estimates of clay, silt, and sand content for each field texture class are given and this allows the field texture classes to be plotted in the texture triangle. There are considerable differences between field texture classes and particle-size classes. Based on the uncertainties in determining the clay content from field texture, we establish the probability of the occurrence of a texture contrast soil according to the Australian Soil Classification system, given the texture of the B2 horizon and its overlying A horizon. I enjoy doing the soil-texture feel test with my fingers or kneading a clay soil, which is a short step from ceramics or sculpture. Hans Jenny (1984)

scholarly journals A Comparative Analysis of a Detailed and Semi-Detailed Soil Mapping for Sustainable Land Management Using Conventional and Currently Applied Methodologies in Greece

Land ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 154 ◽  
Author(s):  
Orestis Kairis ◽  
Vassiliki Dimitriou ◽  
Chrysoula Aratzioglou ◽  
Dionisios Gasparatos ◽  
Nicholas Yassoglou ◽  
...  
Keyword(s):  
Soil Classification ◽  
Botanical Garden ◽  
Soil Mapping ◽  
Classification Systems ◽  
Soil Survey ◽  
Sustainable Land Use ◽  
Soil Taxonomy ◽  
Reference Base ◽  
World Reference Base ◽  
Soil Surveys

Two soil mapping methodologies at different scales applied in the same area were compared in order to investigate the potential of their combined use to achieve an integrated and more accurate soil description for sustainable land use management. The two methodologies represent the main types of soil mapping systems used and still applied in soil surveys in Greece. Diomedes Botanical Garden (DBG) (Athens, Greece) was used as a study area because past cartographic data of soil survey were available. The older soil survey data were obtained via the conventional methodology extensively used over time since the beginnings of soil mapping in Greece (1977). The second mapping methodology constitutes the current soil mapping system in Greece recently used for compilation of the national soil map. The obtained cartographic and soil data resulting from the application of the two methodologies were analyzed and compared using appropriate geospatial techniques. Even though the two mapping methodologies have been performed at different mapping scales, using partially different mapping symbols and different soil classification systems, the description of the soils based on the cartographic symbols of the two methodologies presented an agreement of 63.7% while the soil classification by the two taxonomic systems namely Soil Taxonomy and World Reference Base for Soil Resources had an average coincidence of 69.5%.

A regional analysis of the impact of dams on water temperature in medium-size rivers in eastern Canada

2016 ◽  
Vol 73 (12) ◽  
pp. 1885-1897 ◽  
Author(s):  
Audrey Maheu ◽  
André St-Hilaire ◽  
Daniel Caissie ◽  
Nassir El-Jabi ◽  
Guillaume Bourque ◽  
...  
Keyword(s):  
Water Temperature ◽  
Thermal Regime ◽  
Regional Scale ◽  
Regional Analysis ◽  
Annual Runoff ◽  
Rate Of Change ◽  
Medium Size ◽  
Regulated Rivers ◽  
Eastern Canada ◽  
The Impact

Various studies have helped gain a better understanding of the thermal impacts of dams on a site-specific basis, but very few studies have compared the thermal impacts of varying types of dams within the same region. In this study, we conducted a regional-scale assessment of the impacts of dams on the thermal regime of 13 medium-size rivers in eastern Canada. The objectives of this study were to identify features of the thermal regime of rivers that are predominantly impacted by dams and to compare the impacts associated with different types of regulation (run-of-river, storage, peaking). The thermal regime of regulated and unregulated rivers was characterized using 15 metrics that described the magnitude, frequency, duration, timing, and rate of change of water temperature. Results indicate that storage and peaking dams impounding at least 10% of the median annual runoff generally (i) reduced the magnitude of water temperature variation at seasonal, daily, and subdaily timescales and (ii) increased the monthly mean water temperature in September. This regional assessment offers important insight regarding a generalized pattern of thermal alteration by dams, and this information could be used to guide biological monitoring efforts in regulated rivers.

Spatio-temporal cluster analyses of landslides in Italy at national and regional scale

2020 ◽  
Author(s):  
Marj Tonini ◽  
Kim Romailler ◽  
Gaetano Pecoraro ◽  
Michele Calvello
Keyword(s):  
Cluster Analysis ◽  
Point Processes ◽  
Statistical Significance ◽  
Regional Scale ◽  
Regional Analysis ◽  
Scan Statistics ◽  
Economic Losses ◽  
Campania Region ◽  
Temporal Cluster ◽  
Spatio Temporal

&lt;p&gt;&lt;strong&gt;Keywords:&lt;/strong&gt; Landslides, FraneItalia, cluster analysis, spatio-temporal point process&lt;/p&gt;&lt;p&gt;In Italy landslides pose a significant and widespread risk, resulting in a large number of casualties and huge economic losses. Landslide inventories are critical to support investigations of where and when landslides have happened and may occur in the future, i.e. to establish reliable correlations between triggering factors and landslide occurrences. To deal with this issue, statistical methods originally developed for spatio-temporal stochastic point processes can be useful for identifying correlations between events in space and time and detecting a significant excess of cases within large landslide datasets.&lt;/p&gt;&lt;p&gt;In the present study, the authors propose an approach to analyze and visualize spatio-temporal clusters of landslides occurred in Italy in the period 2010-2017, considering the weather warning zones as territorial units. Besides, a regional analysis was conducted in Campania region considering the municipalities as territorial units. Data on landslide occurrences derived from the FraneItalia catalog, an inventory retrieved from online Italian news. The database contains 8931 landslides, grouped in 4231 single events and 938 areal events (records referring to multiple landslides triggered by the same cause in the same geographic area). Analyses were performed both annually, considering each year individually, and globally, considering the entire frame period. We applied the spatio-temporal scan statistics permutation model (STPSS, integrated in SaTScan&lt;sup&gt;TM&lt;/sup&gt; software), which allowed detecting clusters&amp;#8217; location and estimating their statistical significance. STPSS is based on cylindrical moving windows which scan the area across the space and in time counting the number of observed and expected occurrences and computing the likelihood ratio. The statistical inference (p-value) is evaluated by Monte Carlo sampling and finally the most likely clusters in the real and randomly generated datasets are compared.&lt;/p&gt;&lt;p&gt;Although more detailed analyses are required for the determination of cause-effect relationships among landslides and other variables, some relations with the local topographic and meteorological conditions can already be argued. At national scale, spatio-temporal clusters of landslides are mainly recurrent in two zones: the area enclosing Liguria Region &amp;#8211; Northern Tuscany at north-west and the area between Abruzzo and Molise regions at centre-east. During the year, landslide clusters are particularly abundant between October and March. as most of the events in the FraneItalia catalog are rainfall-induced, strongly influenced by seasonal rainfall patterns. Concerning the regional analysis, most of the clusters are located in the Lattari mountains, the Pizzo d&amp;#8217;Alvano massif and the Picentini mountains, areas highly susceptible to landslide occurrence due to geomorphological factors.&lt;/p&gt;&lt;p&gt;In conclusion, the application of spatio-temporal cluster analysis at various scale allowed the identification of frame periods with greater landslide activity. The question of whether this increase in activity depends climate conditions or topographic factors is still open and request further investigations.&lt;/p&gt;&lt;p&gt;REFERENCES&lt;/p&gt;&lt;p&gt;Calvello, M., Pecoraro, G. FraneItalia: a catalog of recent Italian landslides. &lt;em&gt;Geoenvironmental Disasters&lt;/em&gt;. 5: 13 (2018)&lt;/p&gt;&lt;p&gt;Tonini, M. &amp; Cama, M. Spatio-temporal pattern distribution of landslides causing damage in Switzerland. &lt;em&gt;Landslides&lt;/em&gt; 16 (2019)&lt;/p&gt;

The World Reference Base for Soils (WRB) and Soil Taxonomy: an appraisal of their application to the soils of the Northern Rivers of New South Wales

Soil Research ◽  
2013 ◽  
Vol 51 (3) ◽  
pp. 167 ◽  
Author(s):  
David T. Morand
Keyword(s):  
New South ◽  
New South Wales ◽  
Soil Classification ◽  
Soil Taxonomy ◽  
Reference Base ◽  
South Wales ◽  
The World ◽  
World Reference Base ◽  
Northern Rivers ◽  
Soil Surveys

Few soil surveys in New South Wales have utilised international soil classifications. Extensive morphological and laboratory data collected during soil surveys in the Northern Rivers region provided a strong basis for correlation with the World Reference Base for Soil Resources (WRB), Soil Taxonomy (ST), and the Australian Soil Classification (ASC). Of the 32 reference soil groups comprising the WRB, 20 were present locally; nine of the 12 ST orders were present. After re-classification of soils, correlation of the ASC with the WRB and ST was undertaken. Soils not requiring extensive laboratory analysis for classification and sharing similar central concepts were the more straightforward to correlate. Several ASC orders have unique central concepts and were therefore difficult to correlate with any one WRB reference soil group or ST order/suborder. Other soils were difficult to correlate due to differences in definitions of similar diagnostic criteria. This is most applicable to soils with strong texture-contrast and those with natric conditions. Such soils are not adequately differentiated to suit the Northern Rivers conditions. Of the two international schemes, the WRB was easier to apply locally due to the relative simplicity of the scheme. Considering certain aspects of Australian soils would improve the applicability of the WRB as a truly international framework for soil classification and correlation. Amendments to both the ASC and WRB are suggested.

An attempt of integrating the systematic of urban soils into the new Russian soil classification system

2013 ◽  
Vol 64 (1) ◽  
pp. 24-28 ◽  
Author(s):  
Tatiana Prokof'eva ◽  
Maria Gerasimova ◽  
Irina Lebedeva ◽  
Irina Martynenko
Keyword(s):  
Classification System ◽  
Urban Soils ◽  
Soil Classification ◽  
Parent Material ◽  
Simultaneous Formation ◽  
Natural Properties ◽  
Russian Soil ◽  
Central Image ◽  
Diagnostic Horizons ◽  
Diagnostic Horizon

Abstract An attempt to incorporate the popular systematic of urban soils proposed by Marina Stroganova with colleagues into the new Russian soil classification system is presented. It was facilitated by the coincidence of approaches in both systems: priority of diagnostic horizons and their combinations as criteria to identify soil types being the main units in all Russian classifications. The central image of urban soils . urbanozem . in Stroganova.s system found its due place in the order of stratozems (urbostratozem type) owing to its diagnostic horizon . urbic, which combines artificial and natural properties, and to its simultaneous formation with the parent material.

scholarly journals Parameterization of oceanic whitecap fraction based on satellite observations

2015 ◽  
Vol 15 (15) ◽  
pp. 21219-21269 ◽  
Author(s):  
M. F. M. A. Albert ◽  
M. D. Anguelova ◽  
A. M. M. Manders ◽  
M. Schaap ◽  
G. de Leeuw
Keyword(s):  
Wind Speed ◽  
Regional Scale ◽  
Regional Analysis ◽  
Global Scale ◽  
Sea Spray ◽  
Emission Rates ◽  
Data Set ◽  
Scale Assessment ◽  
Starting Point ◽  
Speed Dependence

Abstract. In this study the utility of satellite-based whitecap fraction (W) values for the prediction of sea spray aerosol (SSA) emission rates is explored. More specifically, the study is aimed at improving the accuracy of the sea spray source function (SSSF) derived by using the whitecap method through the reduction of the uncertainties in the parameterization of W by better accounting for its natural variability. The starting point is a dataset containing W data, together with matching environmental and statistical data, for 2006. Whitecap fraction W was estimated from observations of the ocean surface brightness temperature TB by satellite-borne radiometers at two frequencies (10 and 37 GHz). A global scale assessment of the data set to evaluate the wind speed dependence of W revealed a quadratic correlation between W and U10, as well as a relatively larger spread in the 37 GHz data set. The latter could be attributed to secondary factors affecting W in addition to U10. To better visualize these secondary factors, a regional scale assessment over different seasons was performed. This assessment indicates that the influence of secondary factors on W is for the largest part imbedded in the exponent of the wind speed dependence. Hence no further improvement can be expected by looking at effects of other factors on the variation in W explicitly. From the regional analysis, a new globally applicable quadratic W(U10) parameterization was derived. An intrinsic correlation between W and U10 that could have been introduced while estimating W from TB was determined, evaluated and presumed to lie within the error margins of the newly derived W(U10) parameterization. The satellite-based parameterization was compared to parameterizations from other studies and was applied in a SSSF to estimate the global SSA emission rate. The thus obtained SSA production for 2006 of 4.1 × 1012 kg is within previously reported estimates. While recent studies that account for parameters other than U10 explicitly could be suitable to improve predictions of SSA emissions, we promote our new W(U10) parameterization as an alternative approach that implicitly accounts for these different parameters and helps to improve SSA emission estimates equally well.

Amalgamation and Harmonization of Soil Survey Reports into a Multi-purpose Database

2020 ◽  
Author(s):  
Shane Robert Furze ◽  
Paul Arp
Keyword(s):  
New Brunswick ◽  
Soil Properties ◽  
Vegetation Type ◽  
Soil Classification ◽  
Parent Material ◽  
Soil Survey ◽  
Soil Horizon ◽  
Soil Conditions ◽  
Soil Parent Material ◽  
Soil Surveys

There is a growing demand for standardized, easily accessible and detailed information pertaining to soil and its variability across the landscape. Typically, this information is only available for select areas in the form of local or regional soil surveys reports which are difficult, and costly, to develop. Additionally, soil surveying protocols have changed with time, resulting in inconsistencies between surveys conducted over different periods. This article describes systematic procedures applied to generate an aspatial, terminologically- and unit-consistent, database for forest soils from county-based soil survey reports for the province of New Brunswick, Canada. The procedures involved (i) amalgamating data from individual soil surveys following a hierarchical framework, (ii) summarizing and grouping soil information by soil associations, (iii) assigning correct soil associates to each association, with each soil associate distinguished by drainage classification, (iv) assigning pedologically-correct horizon sequences, as identified in the original soil surveys, to each soil associate, (v) assigning horizon descriptors and measured soil properties to each horizon, as outlined by the Canadian System of Soil Classification, and (vi) harmonizing units of measurement for individual soil properties. Identification and summarization of all soil associations (and corresponding soil associates) was completed with reference to the principal soil-forming factors, namely soil parent material, topographic surface expressions, soil drainage, and dominant vegetation type(s). This procedure, utilizing 17 soil surveys, resulted in an amalgamated database containing 106 soil associations, 243 soil associates, and 522 soil horizon sequences summarizing the variability of forest soil conditions across New Brunswick.

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