Effects of vegetation type on the biogeochemistry of small catchments (Mont Lozere, France)

Building a high-precision, stable, and universal automatic extraction model of the rocky desertification information is the premise for exploring the spatiotemporal evolution of rocky desertification. Taking Guizhou province as the research area and based on MODIS and continuous forest inventory data in China, we used a machine learning algorithm to build a rocky desertification model with bedrock exposure rate, temperature difference, humidity, and other characteristic factors and considered improving the model accuracy from the spatial and temporal dimensions. The results showed the following: (1) The supervised classification method was used to build a rocky desertification model, and the logical model, RF model, and SVM model were constructed separately. The accuracies of the models were 73.8%, 78.2%, and 80.6%, respectively, and the kappa coefficients were 0.61, 0.672, and 0.707, respectively. SVM performed the best. (2) Vegetation types and vegetation seasonal phases are closely related to rocky desertification. After combining them, the model accuracy and kappa coefficient improved to 91.1% and 0.861. (3) The spatial distribution characteristics of rocky desertification in Guizhou are obvious, showing a pattern of being heavy in the west, light in the east, heavy in the south, and light in the north. Rocky desertification has continuously increased from 2001 to 2019. In conclusion, combining the vertical spatial structure of vegetation and the differences in seasonal phase is an effective method to improve the modeling accuracy of rocky desertification, and the SVM model has the highest rocky desertification classification accuracy. The research results provide data support for exploring the spatiotemporal evolution pattern of rocky desertification in Guizhou.

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Satellite monitoring of different vegetation types by differential optical absorption spectroscopy (DOAS) in the red spectral range

Atmospheric Chemistry and Physics ◽

10.5194/acp-7-69-2007 ◽

2007 ◽

Vol 7 (1) ◽

pp. 69-79 ◽

Cited By ~ 20

Author(s):

T. Wagner ◽

S. Beirle ◽

T. Deutschmann ◽

M. Grzegorski ◽

U. Platt

Keyword(s):

Optical Absorption ◽

Absorption Spectroscopy ◽

Spectral Range ◽

Near Infrared ◽

Vegetation Type ◽

Differential Optical Absorption Spectroscopy ◽

Trace Gas ◽

Satellite Monitoring ◽

Optical Absorption Spectroscopy ◽

Vegetation Types

Abstract. A new method for the satellite remote sensing of different types of vegetation and ocean colour is presented. In contrast to existing algorithms relying on the strong change of the reflectivity in the red and near infrared spectral region, our method analyses weak narrow-band (few nm) reflectance structures (i.e. "fingerprint" structures) of vegetation in the red spectral range. It is based on differential optical absorption spectroscopy (DOAS), which is usually applied for the analysis of atmospheric trace gas absorptions. Since the spectra of atmospheric absorption and vegetation reflectance are simultaneously included in the analysis, the effects of atmospheric absorptions are automatically corrected (in contrast to other algorithms). The inclusion of the vegetation spectra also significantly improves the results of the trace gas retrieval. The global maps of the results illustrate the seasonal cycles of different vegetation types. In addition to the vegetation distribution on land, they also show patterns of biological activity in the oceans. Our results indicate that improved sets of vegetation spectra might lead to more accurate and more specific identification of vegetation type in the future.

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Comparison of carbon and nitrogen storage in mineral soils of graminoid and shrub tundra sites, western Greenland

Arctic Science ◽

10.1139/as-2015-0023 ◽

2016 ◽

Vol 2 (4) ◽

pp. 165-182 ◽

Cited By ~ 5

Author(s):

Chelsea L. Petrenko ◽

Julia Bradley-Cook ◽

Emily M. Lacroix ◽

Andrew J. Friedland ◽

Ross A. Virginia

Keyword(s):

Vegetation Type ◽

Mineral Soil ◽

Biotic Interactions ◽

The Arctic ◽

Soil C ◽

N Storage ◽

C Storage ◽

Arctic Soils ◽

C Pools ◽

C And N

Shrub species are expanding across the Arctic in response to climate change and biotic interactions. Changes in belowground carbon (C) and nitrogen (N) storage are of global importance because Arctic soils store approximately half of global soil C. We collected 10 (60 cm) soil cores each from graminoid- and shrub-dominated soils in western Greenland and determined soil texture, pH, C and N pools, and C:N ratios by depth for the mineral soil. To investigate the relative chemical stability of soil C between vegetation types, we employed a novel sequential extraction method for measuring organo-mineral C pools of increasing bond strength. We found that (i) mineral soil C and N storage was significantly greater under graminoids than shrubs (29.0 ± 1.8 versus 22.5 ± 3.0 kg·C·m−2 and 1.9 ± .12 versus 1.4 ± 1.9 kg·N·m−2), (ii) chemical mechanisms of C storage in the organo-mineral soil fraction did not differ between graminoid and shrub soils, and (iii) weak adsorption to mineral surfaces accounted for 40%–60% of C storage in organo-mineral fractions — a pool that is relatively sensitive to environmental disturbance. Differences in these C pools suggest that rates of C accumulation and retention differ by vegetation type, which could have implications for predicting future soil C pool storage.

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Body size and mean individual biomass variation of ground-beetles community (Coleoptera: Carabidae) as a response to increasing altitude and associated vegetation types in mountainous ecosystem

Biologia ◽

10.1515/biolog-2017-0114 ◽

2017 ◽

Vol 72 (9) ◽

Cited By ~ 1

Author(s):

Aleksandra Cvetkovska-Gjorgjievska ◽

Slavčo Hristovski ◽

Dana Prelić ◽

Lucija Šerić Jelaska ◽

Valentina Slavevska-Stamenković ◽

...

Keyword(s):

Body Size ◽

Altitudinal Gradient ◽

Vegetation Type ◽

Ground Beetle ◽

Vegetation Types ◽

Forest Stands ◽

Geologic History ◽

White Oak ◽

Mountain Ecosystems ◽

Individual Biomass

AbstractCarabid fauna is not sufficiently explored in Central and Western Balkan areas, especially in mountain ecosystems with unique biodiversity which is a result of specific environmental factors and geologic history. Furthermore, distribution of species and adaptation to varying environmental parameters change along the altitudinal gradients. All this highlights the need for biodiversity and ecological studies in order to assess the state of the mountain ecosystems and conservation significance. Carabids as good bioindicator group can be used as a tool for monitoring those changes. The aim of this study was to analyse the differences of body size distribution and mean individual biomass (MIB) of ground beetle assemblages as a response of changing conditions and vegetation types along an altitudinal gradient on Belasitsa Mountain in south Macedonia. Both parameters significantly decreased with increasing altitude and were consequently associated with the vegetation type. Larger bodied individuals and higher values of MIB were recorded in the white oak and oriental hornbeam forest stands with the values decreasing in sessile oak forests towards submontane and montane beech forest stands. This research yielded first list of carabid species inhabiting Belasitsa Mountain with insight of carabid body length and biomass distribution along altitudinal gradient.

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Alpine and Subalpine Wetland Vegetation on the Bogong High Plains, South-eastern Australia

Australian Journal of Botany ◽

10.1071/bt97106 ◽

1999 ◽

Vol 47 (2) ◽

pp. 165 ◽

Cited By ~ 31

Author(s):

C.-H. Wahren ◽

R. J. Williams ◽

W. A. Papst

Keyword(s):

Soil Depth ◽

Vegetation Type ◽

Soil Surface ◽

Wetland Vegetation ◽

High Plains ◽

Composition And Structure ◽

Eastern Australia ◽

Drainage Channels ◽

Floristic Variation ◽

Steep Slopes

The botanical composition and structure of wetland vegetation from seven sites in the alpine and subalpine tracts of the Bogong High Plains was sampled in 1995 and 1996. Sites were in the vicinity of Mts Nelse, Cope and Fainter. Sampling was based on contiguous 1-m2 quadrats along transects 20−70 m long across each wetland. Samples were ordinated using non-metric multidimensional scaling (NMDS). Floristic variation was assessed both within selected individual wetlands, and between wetlands from different regions. The relationship between the ordinations and environmental variables such as soil surface texture, soil depth and the amount of bare ground was tested by fitting vectors. Three dominant vegetation assemblages were identified. Closed heath, of hygrophyllous, scleromorphic shrubs such as Richea continentis and Baeckea gunniana, the rush Empodisma minus and the moss Sphagnum cristatum occurred on the deeper peats. Low open heath of Epacris glacialis and Danthonia nivicola occurred on shallow peats. Herbfields of Caltha introloba and Oreobolus pumilio occurred on stony pavements in two different physiographic situations&horbar;on relatively steep slopes (10−20°) at the head of wetlands, and on flat ground (slope < 2°), below the head of wetlands. The pavements on the steeper sites appeared to be associated with periglacial features such as solifluction lobes and terraces. Those on the flatter ground appeared to have been derived more recently. Wetlands in the Mt Cope region consisted of closed heath, low open heath and pavement herbfield in various proportions. Wetlands on Mt Fainter, which are subject to heavy trampling by cattle, were in a degraded condition, with a low cover of major hygrophyllous mosses and shrubs, and a high cover of introduced species. Long-ungrazed wetlands in a 50-year exclosure at Rocky Valley had high cover of closed heath, no pavements, numerous ponds and virtually no entrenched drainage channels or exposed peat. The Caltha herbfields are significant features nationally, both floristically and geomorphologically. Alpine and subalpine wetlands have been listed under the Victorian Flora and Fauna Guarantee Act 1988, and continued grazing by cattle is not compatible with the conservation objectives for this alpine vegetation type.

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Model-based coefficient method for calculation of N leaching from agricultural fields applied to small catchments and the effects of leaching reducing measures

Journal of Hydrology ◽

10.1016/j.jhydrol.2004.07.038 ◽

2005 ◽

Vol 304 (1-4) ◽

pp. 343-354 ◽

Cited By ~ 19

Author(s):

K. Kyllmar ◽

K. Mårtensson ◽

H. Johnsson

Keyword(s):

Agricultural Fields ◽

N Leaching ◽

Model Based ◽

Coefficient Method ◽

Small Catchments

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Spatial-Temporal Patterns and Controls of Evapotranspiration across the Tibetan Plateau (2000–2012)

Advances in Meteorology ◽

10.1155/2017/7082606 ◽

2017 ◽

Vol 2017 ◽

pp. 1-12 ◽

Cited By ~ 12

Author(s):

Hao Zhang ◽

Jian Sun ◽

Junnan Xiong

Keyword(s):

Tibetan Plateau ◽

Environmental Factors ◽

Vegetation Type ◽

Middle Part ◽

Rate Of Change ◽

Ecological Indicator ◽

The Tibetan Plateau ◽

Grassland Ecosystems ◽

Key Factor ◽

Positive Correlations

Evapotranspiration (ET) is a key factor to further our understanding of climate change processes, especially on the Tibetan Plateau, which is sensitive to global change. Herein, the spatial patterns of ET are examined, and the effects of environmental factors on ET at different scales are explored from the years 2000 to 2012. The results indicated that a steady trend in ET was detected over the past decade. Meanwhile, the spatial distribution shows an increase of ET from the northwest to the southeast, and the rate of change in ET is lower in the middle part of the Tibetan Plateau. Besides, the positive effect of radiation on ET existed mainly in the southwest. Based on the environment gradient transects, the ET had positive correlations with temperature (R>0.85, p<0.0001), precipitation (R > 0.89, p < 0.0001), and NDVI (R > 0.75, p < 0.0001), but a negative correlation between ET and radiation (R = 0.76, p < 0.0001) was observed. We also found that the relationships between environmental factors and ET differed in the different grassland ecosystems, which indicated that vegetation type is one factor that can affect ET. Generally, the results indicate that ET can serve as a valuable ecological indicator.

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California's Historic Legacy For Landscape Change, the Wieslander Vegetation Type Maps

Madroño ◽

10.3120/0024-9637-63.4.293 ◽

2016 ◽

Vol 63 (4) ◽

pp. 293-328 ◽

Cited By ~ 2

Author(s):

James H. Thorne ◽

Thuy N'goc Le

Keyword(s):

Landscape Change ◽

Vegetation Type

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