Early seedling establishment of Picea abies in small forest gaps in the Swiss Alps

1998 ◽  
Vol 28 (4) ◽  
pp. 626-639 ◽  
Author(s):  
Peter Brang
Keyword(s):  
Picea Abies ◽  
Swiss Alps ◽  
North Slope ◽  
Organic Layer ◽  
The South ◽  
Direct Sunlight ◽  
The North ◽  
South Slope ◽  
Early Seedling ◽  
Small Forest

Early seedling establishment of Picea abies (L.) Karst. in small forest gaps was studied in drier, subalpine P. abies ecosystems in the Swiss Alps. Study sites were on steep south and north slopes. Average gap size was 15 m x 20 m on the south slope and 15 m x 70 m on the north slope. Sowing trials established on different microsites were observed for 2 or 3 years. Direct sunlight was assessed with hemispherical photography. Emergence was better on the north slope than on the south slope. On the south slope, emergence was higher on the mineral soil than on the organic layer and was negatively associated with direct sunlight, especially during the noon period. On both slopes, drought due to rainfall interception at the gap edge negatively affected emergence. The limiting factor for survival and growth on the south slope was drought (on the organic layer), whereas on the north slope lack of direct radiation and pathogenic fungi developing in the snowpack were limiting. The early regeneration niche on the south slope was narrower than on the north slope.

scholarly journals Snowmelt Hydrology of Two Subarctic Slopes, Southern Yukon, Canada

1998 ◽  
Vol 29 (4-5) ◽  
pp. 331-346 ◽  
Author(s):  
Sean K. Carey ◽  
Ming-ko Woo
Keyword(s):  
Organic Soil ◽  
Organic Layer ◽  
Runoff Generation ◽  
The South ◽  
The North ◽  
Local Topography ◽  
South Slope ◽  
Mineral Soils ◽  
Aspen Forest ◽  
North And South

Large quantities of water are discharged from subarctic basins during snowmelt season. Runoff contributing areas as well as timing and magnitude of meltwater generation from different slopes are highly variable. Two slopes in the lower Wolf Creek basin, southern Yukon, were studied in 1997. The south-facing slope has a dense aspen forest that is leafless in the melt period (April – May) and is underlain by seasonal frost. The north-facing slope has open stands of spruce and an organic layer that rests on mineral soils with permafrost. In 1997, snowmelt is advanced by over 10 days on the south slope, which receives more solar radiation than the north aspect. All meltwater on the south slope infiltrates the frozen silt without generating runoff. By the time significant melt events occur on the north slope the frost and snow are gone from the south. Meltwater is able to infiltrate the frozen organic soil but deep percolation is prevented by the ice-rich substrate. Lateral flow begins after the organic layer is saturated, with much runoff along intermittent rills fed by diffuse and pipe flows. Rills and pipes are interconnected but the drainage network and runoff contributing area change depending on the disposition of the snow as well as water and frost table positions relative to local topography. Contrasts between the north and south slopes have important implications on direct runoff generation during the melt period. Situations similar to the study site can be found elsewhere in subarctic North America and the observed processes have a bearing upon hydrological modelling for the subarctic environment.

scholarly journals Monitoring the Spatiotemporal Difference in Glacier Elevation on Bogda Mountain from 2000 to 2017

2021 ◽  
Vol 18 (12) ◽  
pp. 6374
Author(s):  
Weibing Du ◽  
Ningke Shi ◽  
Linjuan Xu ◽  
Shiqiong Zhang ◽  
Dandan Ma ◽  
...  
Keyword(s):  
Water Supply ◽  
Radar Data ◽  
Surface Elevation ◽  
North Slope ◽  
The South ◽  
Glacier Surface ◽  
Study Region ◽  
The North ◽  
South Slope ◽  
The Difference

The difference in glacier surface elevation is a sensitive indicator of climate change and is also important for disaster warning and water supply. In this paper, 25 glaciers on Bogda Mountain, in the eastern Tianshan Mountains, are selected as the study object as they are typical of glaciers in arid or semi-arid areas with importance for water supply. The Repeat Orbit Interferometry (ROI) method is used to survey the surface elevation of these glaciers using Sentinel-1A Radar data from 2017. Using data from the Shuttle Radar Topography Mission (SRTM) and a Digital Elevation Model (DEM), the difference in the glacier surface elevation between 2000 and 2017 is obtained. A scheme to evaluate the accuracy of estimated variations in glacier surface elevation is proposed in this article. By considering the surfaces of lakes in the study region as ideal horizontal planes, the average standard deviation (SD) value of the lake elevation is taken as the error caused by the radar sensor and observing conditions. The SD of the lake elevation is used as an index to evaluate the error in the estimated variation of the glacier surface elevation, and the obtained SD values indicate that the result obtained using the ROI method is reliable. Additionally, the glacier surface elevation variation pattern and a Logarithmic Fitting Model (LFM) are used to reduce the error in high-altitude glacial accumulation areas to improve the estimation of the difference in the glacier surface elevation obtained using ROI. The average SD of the elevation of the 12 lakes is ±2.87 m, which shows that the obtained glacier surface elevations are reliable. This article concludes that, between 2000 and 2017, the surface elevation of glaciers on Bogda Mountain decreased by an average of 11.6 ± 1.3 m, corresponding to an average decrease rate of 0.68 m/a, and glaciers volume decreased by an average of 0.504 km3. Meanwhile, the surface elevations of the lakes increased by an average of 8.16 m. The decrease of glacier surface elevation leads to the expansion of glacial lakes. From the north slope clockwise to the south slope, the glacier elevation variation showed a decreasing trend, and the elevation variation gradually increased from the south slope to the north slope. With the increase of glacier altitude, the variation of glacier surface elevation gradually changed from negative to positive. The findings of this article suggest that the rate of glacier retreat on Bogda Mountain increased from 2000 to 2017.

scholarly journals Nitrogen isotopic composition of plants and soil in an arid mountainous terrain: south slope versus north slope

2018 ◽  
Vol 15 (1) ◽  
pp. 369-377 ◽  
Author(s):  
Chongjuan Chen ◽  
Yufu Jia ◽  
Yuzhen Chen ◽  
Imran Mehmood ◽  
Yunting Fang ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Environmental Effects ◽  
Influential Factors ◽  
N Cycling ◽  
North Slope ◽  
Soil N ◽  
The South ◽  
The North ◽  
South Slope ◽  
Soil Δ15n

Abstract. Nitrogen cycling is tightly associated with environment. The south slope of a given mountain could significantly differ from north slope in environment. Thus, N cycling should also be different between the two slopes. Since leaf δ15N, soil δ15N and Δδ15Nleaf-soil (Δδ15Nleaf-soil =  leaf δ15N − soil δ15N) could reflect the N cycling characteristics, we put forward a hypothesis that leaf δ15N, soil δ15N and Δδ15Nleaf-soil should differ between the two slopes. However, such a comparative study between two slopes has never been conducted. In addition, environmental effects on leaf and soil δ15N derived from studies at global scale were often found to be different from those on a regional scale. This led to our argument that environmental effects on leaf and soil δ15N could depend on local environment. To confirm our hypothesis and argument, we measured leaf and soil δ15N on the south and north slopes of Tian Shan. Remarkable environmental differences between the two slopes provided an ideal opportunity for our test. The study showed that leaf δ15N, soil δ15N and δ15Nleaf-soil on the south slope were greater than those on the north slope, although the difference in soil δ15N was not significant. The result confirmed our hypothesis and suggested that the south slope has higher soil N transformation rates and soil N availability than the north slope. In addition, in this study it was observed that the significant influential factors of leaf δ15N were temperature, precipitation, leaf N, leaf C ∕ N, soil moisture and silt ∕ clay ratio on the north slope, whereas on the south slope only leaf C ∕ N was related to leaf δ15N. The significant influential factors of soil δ15N were temperature, precipitation, soil moisture and silt ∕ clay ratio on the north slope, whereas on the south slope, mean annual precipitation and soil moisture exerted significant effects. Precipitation exerted contrary effects on soil δ15N between the two slopes. Thus, this study supported our argument that the relationships between leaf and soil δ15N and environmental factors are localized.

Feeding rhythm of Diaphus chrysorhynchus on the north slope of the South China Sea

2018 ◽  
Vol 25 (2) ◽  
pp. 395
Author(s):  
Zhongyi LI ◽  
Yaoyao YANG ◽  
Yiping YING ◽  
Zuozhi CHEN ◽  
Xinliang WANG ◽  
...  
Keyword(s):  
South China Sea ◽  
South China ◽  
The South China Sea ◽  
North Slope ◽  
The South ◽  
China Sea ◽  
The North ◽  
Feeding Rhythm

1. On Grooved and Striated Rocks in the Middle Region of Scotland.

1851 ◽  
Vol 2 ◽  
pp. 233-234
Author(s):  
Charles Maclaren
Keyword(s):  
Swiss Alps ◽  
Middle Region ◽  
The South ◽  
The North

In this paper an account was given of grooved, striated, and abraded rocks in various parts of Scotland, from Glen Spean on the north, to the Pentland and Lammermoor Hills on the south. After indicating the direction in which the groovings pointed, it was shewn,—that the appearance of these grooved and striated rocks is irreconcilable with the hypothesis which ascribes the phenomena to a supposed great Atlantic wave or transient flood, of which one part swept across the low lands of Scotland, while another part was turned back by the mountains,—that in the district between the Clyde and the Spean, where the largest and best marked groovings were observed, there is satisfactory evidence to prove, that they were produced by bodies of vast depth occupying the valleys, moving from the mountain group as a common centre, toward the coast and the Lowlands in all directions, and exerting an immense force of pressure vertically and laterally,—that this quaquaversal motion, as well as the form, position, and size of the groovings, are conclusive against the idea that they were caused by currents of water loaded with stones and gravel, since no collected mass of water exists, or could exist, of the requisite magnitude and elevation, to send out streams in all directions capable of acting powerfully at the height of a thousand feet or more above the bottoms of the valleys,—that the effects mentioned, therefore, can only be accounted for by the agency of glaciers, as exemplified in the Swiss Alps.

scholarly journals Abiotic and biotic determinants of height growth of Picea abies regeneration in small forest gaps in the Swiss Alps

2021 ◽  
Vol 490 ◽  
pp. 119076
Author(s):  
Ueli Schmid ◽  
Christof Bigler ◽  
Monika Frehner ◽  
Harald Bugmann
Keyword(s):  
Picea Abies ◽  
Height Growth ◽  
Swiss Alps ◽  
Forest Gaps ◽  
Small Forest

scholarly journals Infection Levels of the Microsporidium Larssoniella duplicati in Populations of the Invasive Bark Beetle Ips duplicatus: From Native to New Outbreak Areas

Forests ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 131 ◽  
Author(s):  
Soňa Zimová ◽  
Karolina Resnerová ◽  
Hana Vanická ◽  
Jakub Horák ◽  
Jiří Trombik ◽  
...  
Keyword(s):  
Picea Abies ◽  
Bark Beetle ◽  
The South ◽  
Infection Level ◽  
The North ◽  
Ips Duplicatus ◽  
Specific Pathogen ◽  
Outbreak Areas ◽  
Study Sites ◽  
A Site

The microsporidium Larssoniella duplicati (Weiser, Holuša, Žižka, 2006) is a specific pathogen of the bark beetle Ips duplicatus (C.R. Sahlberg, 1836), which is a serious pest of Norway spruce (Picea abies (L.) H. Karst) in Europe. From 2011 to 2016, infection levels of L. duplicati and other pathogens in I. duplicatus populations were assessed along a gradient, ranging from areas in the north, where the beetle is native, to areas in the south, where the beetle has only recently invaded. The 21 study sites ranged in altitude from 229 to 1009 m a.s.l. We found that pathogen infection levels in I. duplicatus populations decreased from the native areas in the north to the new areas of beetle expansion in the south. We also found that pathogen level increased with altitude. The L. duplicati infection levels were not associated with the infection levels of other beetle natural enemies. The infection level decreased with the length of time of beetle establishment in an area. The infection level increased with the number of beetles trapped and dissected at a site.

Long-term Cyclic Variations of Prominences, Green and Red Coronae over Solar Cycles

2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský
Keyword(s):  
Emission Lines ◽  
High Latitudes ◽  
Green Line ◽  
Solar Cycles ◽  
The South ◽  
Coronal Emission ◽  
Local Maxima ◽  
The North ◽  
Cyclic Variations

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.

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