Brunisolic soils of Canada: Genesis, distribution, and classification

2011 ◽  
Vol 91 (5) ◽  
pp. 695-717 ◽  
Author(s):  
C. A. S. Smith ◽  
K. T. Webb ◽  
E. Kenney ◽  
A. Anderson ◽  
D. Kroetsch

Smith, C. A. S., Webb, K. T., Kenney, E., Anderson, A. and Kroetsch, D. 2011. Brunisolic soils of Canada: Genesis, distribution, and classification. Can. J. Soil Sci. 91: 695–717. Brunisols are considered as moderately developed soils formed under forest cover. They have a wide range of physical and chemical properties and no single dominant pedogenic process drives the development of these soils. Brunisols are some of the more common soils in Canada, occupying over 1.2 million km2 of land, roughly equivalent to the area of Podzolic soils, and about half the area of the most common soil order in Canada, the Cryosols. Brunisols occur mainly within the boreal forest regions, but extend across the country with the exception of the Arctic and prairie regions. Within the zone of discontinuous permafrost they co-exist on landscapes with Cryosols. In humid regions of both eastern and western Canada they form a continuum of soil development with Podzolic soils. Within subhumid to semi-arid regions they often co-exist with Luvisolic soils, occurring on parent materials too coarse to enable Luvisolic soil formation. Brunisols equate closely to the Cambisol reference group in the World Reference Base taxonomic system and to several suborders of the Inceptisol order in Soil Taxonomy. Both Melanic and Sombric Brunisols are important agricultural soils in British Columbia, Ontario and the Maritime provinces. Eutric and Dystric Brunisols support commercial forest stands throughout the boreal forest and western cordillera of Canada.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jiangwen Li ◽  
Jing Du ◽  
Shouqin Zhong ◽  
En Ci ◽  
Chaofu Wei

AbstractThe study of the pedogenic process in response to natural evolution, gradual anthropogenic shifts and engineering upheavals is of great significance for understanding, utilizing and transforming nature in the future. Although scholars have considered anthropic activities to be an important factor affecting pedogenesis, research on how and how much anthropic activities influence the soil-forming process is scant. This paper was conducted to analyse pedogenic characteristics dominated by anthropic activities. In this study, the parent materials and soils undergoing natural evolution (NE), tillage perturbation (TP) and engineering perturbation (EP) were selected as research objects. The genetic characteristics of soils undergoing NE, TP and EP are investigated mainly from three aspects: soil profile macromorphological characteristics, soil physical and chemical properties and chemical weathering characteristics. The results indicated that the influence of anthropic activities (TP and EP) on the process of pedogenesis is complicated. First, compared with NE, TP decreases the thickness of topsoil from 22.2 to 21.2 cm, while EP increases the thickness of topsoil from 22.2 to 23.2 cm, and EP causes the soil to have a high profile development index. Second, compared with TP, EP can improve bulk density (BD), soil organic carbon (SOC), total nitrogen (TN) and cation exchange capacity (CEC), Finally, the chemical weathering intensity differed among NE, TP and EP and followed the order of TP > NE > EP. Therefore, in the future, the genetic characteristics of soils dominated by anthropic activities should be considered. This will help us systematically understand the genesis and evolutionary characteristics of soil and lay a foundation for further perfecting the diagnostic horizon and diagnostic characteristics of the Soil Taxonomy and World Reference Base.



2017 ◽  
Vol 9 (1) ◽  
pp. 317-348 ◽  
Author(s):  
Sina Muster ◽  
Kurt Roth ◽  
Moritz Langer ◽  
Stephan Lange ◽  
Fabio Cresto Aleina ◽  
...  

Abstract. Ponds and lakes are abundant in Arctic permafrost lowlands. They play an important role in Arctic wetland ecosystems by regulating carbon, water, and energy fluxes and providing freshwater habitats. However, ponds, i.e., waterbodies with surface areas smaller than 1. 0 × 104 m2, have not been inventoried on global and regional scales. The Permafrost Region Pond and Lake (PeRL) database presents the results of a circum-Arctic effort to map ponds and lakes from modern (2002–2013) high-resolution aerial and satellite imagery with a resolution of 5 m or better. The database also includes historical imagery from 1948 to 1965 with a resolution of 6 m or better. PeRL includes 69 maps covering a wide range of environmental conditions from tundra to boreal regions and from continuous to discontinuous permafrost zones. Waterbody maps are linked to regional permafrost landscape maps which provide information on permafrost extent, ground ice volume, geology, and lithology. This paper describes waterbody classification and accuracy, and presents statistics of waterbody distribution for each site. Maps of permafrost landscapes in Alaska, Canada, and Russia are used to extrapolate waterbody statistics from the site level to regional landscape units. PeRL presents pond and lake estimates for a total area of 1. 4 × 106 km2 across the Arctic, about 17 % of the Arctic lowland ( <  300 m a.s.l.) land surface area. PeRL waterbodies with sizes of 1. 0 × 106 m2 down to 1. 0 × 102 m2 contributed up to 21 % to the total water fraction. Waterbody density ranged from 1. 0 × 10 to 9. 4 × 101 km−2. Ponds are the dominant waterbody type by number in all landscapes representing 45–99 % of the total waterbody number. The implementation of PeRL size distributions in land surface models will greatly improve the investigation and projection of surface inundation and carbon fluxes in permafrost lowlands. Waterbody maps, study area boundaries, and maps of regional permafrost landscapes including detailed metadata are available at https://doi.pangaea.de/10.1594/PANGAEA.868349.



Author(s):  
Larry D. Hinzman ◽  
Leslie A. Viereck

There are large climatic differences among the boreal regions of the world. The extreme continental climates of central Siberia, with a mean annual temperature of –11°C or colder and precipitation of only 150 mm, for example, contrasts strikingly with the semicoastal climate of Newfoundland, with a mean annual temperature of +5°C and precipitation of 1400 mm. Yet both are considered boreal. This wide range in mean annual temperatures translates into large variation in the soil thermal conditions. Although much of the northern region of the boreal forest is underlain by continuous and discontinuous permafrost, southern regions are entirely permafrost-free. Boreal Canada has been classified into four major ecoclimatic provinces (Ecoregions Working Group 1989). The Subarctic Ecoclimatic Province extends from treeline in northern Canada south to the border with continuous stands of closed spruce. It ranges from the highly continental areas of northern Yukon Territory to the wetter and somewhat warmer regions of the Labrador Peninsula. The Boreal Ecoclimatic Province includes the main body of the boreal forests of Canada from the Mackenzie River east to Newfoundland. It is a complicated province that has been divided into High, Mid-, and Low Boreal, with a wide range of climate conditions. The Subarctic Cordilleran Ecoclimatic Province occurs only at higher elevations in western Canada. Forested areas in this region are usually restricted to valley bottoms or low, south-facing slopes. The Cordilleran Ecoclimatic Province includes the mountain ranges along the west coast and the continental divide from Montana to Alaska and from the Yukon River south to the boundary with the coastal forests. The boreal portion of this province has climates similar to that of the eastern section of the Interior Highland Ecoregion of Alaska (Fig. 2.3, Gallant et al. 1995). Alaska does not fit well into these Canadian ecoclimatic provinces because of differences in elevation, the effects of the two east-west-oriented mountain ranges (the Alaska and Brooks Ranges), and the coastal influences of the Bering Sea to the west and Cook Inlet to the south (Fig. 1.1; Hopkins 1959, Hare and Ritchie 1972). Hammond and Yarie (1996) separated Alaska into 35 ecoclimatic regions, of which nine include areas of boreal forest.



2016 ◽  
Author(s):  
Sina Muster ◽  
Kurt Roth ◽  
Moritz Langer ◽  
Stephan Lange ◽  
Fabio Cresto Aleina ◽  
...  

Abstract. Ponds and lakes are abundant in Arctic permafrost lowlands. They play an important role in Arctic wetland ecosystems by regulating carbon, water, and energy fluxes and providing freshwater habitats. However, ponds, i.e. waterbodies with surface areas smaller than 1.0E+04 m2, have not been inventoried at global and regional scales. The Permafrost Region Pond and Lake Database (PeRL) presents the results of a circum-arctic effort to map ponds and lakes from modern (2002–2013) high-resolution aerial and satellite imagery with a resolution of 5 m or better that resolve waterbodies with a surface area between 1.0E+02 m2 and 1.0E+06 m2. The database also includes historical imagery from 1948 to 1965 with a resolution of 6 m or better. PeRL includes 69 maps covering a wide range of environmental conditions from tundra to boreal regions and from continuous to discontinuous permafrost zones. Waterbody maps are linked to regional permafrost landscape maps which provide information on permafrost extent, ground ice volume, geology and lithology. This paper describes waterbody classification and accuracy, and presents statistics of waterbody distribution for each site. Maps of permafrost landscapes in Alaska, Canada and Russia are used to extrapolate waterbody statistics from the site level to regional landscape units. PeRL presents pond and lake estimates for a total area of 1.4E+06 km2 across the Arctic, about 17 % of the Arctic lowland (



Author(s):  
Sergei Soldatenko ◽  
Sergei Soldatenko ◽  
Genrikh Alekseev ◽  
Genrikh Alekseev ◽  
Alexander Danilov ◽  
...  

Every aspect of human operations faces a wide range of risks, some of which can cause serious consequences. By the start of 21st century, mankind has recognized a new class of risks posed by climate change. It is obvious, that the global climate is changing, and will continue to change, in ways that affect the planning and day to day operations of businesses, government agencies and other organizations and institutions. The manifestations of climate change include but not limited to rising sea levels, increasing temperature, flooding, melting polar sea ice, adverse weather events (e.g. heatwaves, drought, and storms) and a rise in related problems (e.g. health and environmental). Assessing and managing climate risks represent one of the most challenging issues of today and for the future. The purpose of the risk modeling system discussed in this paper is to provide a framework and methodology to quantify risks caused by climate change, to facilitate estimates of the impact of climate change on various spheres of human activities and to compare eventual adaptation and risk mitigation strategies. The system integrates both physical climate system and economic models together with knowledge-based subsystem, which can help support proactive risk management. System structure and its main components are considered. Special attention is paid to climate risk assessment, management and hedging in the Arctic coastal areas.



2003 ◽  
Vol 79 (1) ◽  
pp. 132-146 ◽  
Author(s):  
Dennis Yemshanov ◽  
Ajith H Perera

We reviewed the published knowledge on forest succession in the North American boreal biome for its applicability in modelling forest cover change over large extents. At broader scales, forest succession can be viewed as forest cover change over time. Quantitative case studies of forest succession in peer-reviewed literature are reliable sources of information about changes in forest canopy composition. We reviewed the following aspects of forest succession in literature: disturbances; pathways of post-disturbance forest cover change; timing of successional steps; probabilities of post-disturbance forest cover change, and effects of geographic location and ecological site conditions on forest cover change. The results from studies in the literature, which were mostly based on sample plot observations, appeared to be sufficient to describe boreal forest cover change as a generalized discrete-state transition process, with the discrete states denoted by tree species dominance. In this paper, we outline an approach for incorporating published knowledge on forest succession into stochastic simulation models of boreal forest cover change in a standardized manner. We found that the lack of details in the literature on long-term forest succession, particularly on the influence of pre-disturbance forest cover composition, may be limiting factors in parameterizing simulation models. We suggest that the simulation models based on published information can provide a good foundation as null models, which can be further calibrated as detailed quantitative information on forest cover change becomes available. Key words: probabilistic model, transition matrix, boreal biome, landscape ecology



2015 ◽  
Vol 23 (4) ◽  
pp. 461-479 ◽  
Author(s):  
Robie W. Macdonald ◽  
Zou Zou A. Kuzyk ◽  
Sophia C. Johannessen

The sediments of the pan-Arctic shelves contribute an important component to the Arctic Ocean ecosystem by providing a habitat for biota (benthos), a repository for organic and inorganic non-conservative substances entering or produced within the ocean, a reactor and source of transformed substances back to the water column, and a mechanism of burial. Sediments interact with ice, ocean, and the surrounding land over a wide range of space and time scales. We discuss the vulnerability of shelf sediment to changes in (i) organic carbon sources, (ii) pathways of sediment and organic carbon supply, and (iii) physical and biogeochemical alteration (diagenesis). Sedimentary environments of the shelves and basins are likely to exhibit a wide variance in their response to global change because of their wide variation in sediment sources, processes, and metabolic conditions. In particular, the Chukchi and Barents shelves are dominated by inflowing waters from oceans to the south, whereas the interior shelves are more closely tied to terrigenous sources due to river inflow and coastal erosion.



2011 ◽  
Vol 41 (3) ◽  
pp. 501-508 ◽  
Author(s):  
Ambroise Lycke ◽  
Louis Imbeau ◽  
Pierre Drapeau

Partial cuts are increasingly proposed to maintain habitats for species negatively affected by clearcutting, even if their benefits on nonpasserine birds and large mammals are still poorly documented. Our main objective was to evaluate effects of commercial thinning (CT) on spruce grouse ( Falcipennis canadensis L.), a game bird of the boreal forest. Because this species is known to be associated with a dense vegetation cover, we hypothesized that habitat use would be lower in treated sites. In spring 2006, we evaluated site occupancy in 94 forest stands (50 CT and 44 uncut stands) in Quebec by visiting each on three occasions during the breeding season (March–May). Additionally, during the molting period (May–July), we used radiotelemetry to monitor habitat use by 19 males. As compared with uncut stands, results show that a lower proportion of CTs were used in spring (39% versus 60%, after accounting for detection). During the molting period, CTs were also used less than expected according to their availability. The significant reduction of lateral and vertical forest cover in CT may explain these results. We conclude that even if CT is perceived beneficial for wildlife, it does not completely fulfill the needs of species associated with dense understory vegetation, such as spruce grouse.



2016 ◽  
Author(s):  
Mike J. Newland ◽  
Patricia Martinerie ◽  
Emmanuel Witrant ◽  
Detlev Helmig ◽  
David R. Worton ◽  
...  

Abstract. The NOX (NO and NO2) and HOX (OH and HO2) budgets of the atmosphere exert a major influence on atmospheric composition, controlling removal of primary pollutants and formation of a wide range of secondary products, including ozone, that can influence human health and climate. However, there remain large uncertainties in the changes to these budgets over recent decades. Due to their short atmospheric lifetimes, NOX and HOX are highly variable in space and time, and so the measurements of these species are of very limited value for examining long term, large scale changes to their budgets. Here, we take an alternative approach by examining long-term atmospheric trends of alkyl nitrates, the formation of which is dependent on the atmospheric NO / HO2 ratio. We derive long term trends in the alkyl nitrates from measurements in firn air from the NEEM site, Greenland. Their mixing ratios increased by a factor of 4–5 between the 1970s and 1990s. This was followed by a steep decline to the sampling date of 2008. Moreover, we examine how the trends in the alkyl nitrates compare to similarly derived trends in their parent alkanes (i.e. the alkanes which, when oxidised in the presence of NOX, lead to the formation of the alkyl nitrates). The ratios of the alkyl nitrates to their parent alkanes increase from around 1970 to the late 1990's consistent with large changes to the [NO] / [HO2] ratio in the northern hemisphere atmosphere during this period. These could represent historic changes to NOX sources and sinks. Alternatively, they could represent changes to concentrations of the hydroxyl radical, OH, or to the transport time of the air masses from source regions to the Arctic.



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