Long-term dynamics of the hemiparasite Rhinanthus angustifolius and its relationship with vegetation structure

Invasive nonnative grasses pose a significant threat to rangelands of the Northern Great Plains. Long-term data from a grazing experiment near Mandan, ND (46°46′11.43″N, 100°54′55.16″W) revealed the invasion of native prairie by Kentucky bluegrass, an exotic grass. We hypothesized that bluegrass invasion altered soil13C and15N levels, tracking the increased abundance of invasive cool-season grass aboveground. In 2014, soil samples were collected to depths of 0 to 7.6 cm and 7.6 to 15.2 cm in pastures grazed similarly since 1916. Samples were analyzed for total carbon (C) and nitrogen (N) and13C and15N isotopes and compared against archived samples from 1991. Vegetation change from native to exotic grasses changed the isotopic composition of soil C. The soil δ13C at the 0- to 7.6-cm depth became more negative between 1991 and 2014. Soil δ13C became less negative with increasing stocking rate at both soil depths. Soil δ15N values at the 0- to 7.6-cm depth decreased between 1991 and 2014. Soil δ15N increased with increasing stocking rate at the 0- to 7.6-cm depth in 2014. Soil C and N concentrations at 0 to 7.6 cm increased by 35% (12 g C kg−1) and 27% (0.9 g N kg−1), respectively, from 1991 to 2014; however, concentrations at the 7.6- to 15.2-cm depth did not change. The shift from native C4to invasive C3grass did not reduce soil C storage in the long-term prairie pastures. The more deleterious effect of invasion, however, may have been the buildup of dead biomass, which alters vegetation structure and may reduce native species’ diversity and abundance.

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The long term effects of thinning treatments on vegetation structure and water yield

Forest Ecology and Management ◽

10.1016/j.foreco.2013.09.046 ◽

2013 ◽

Vol 310 ◽

pp. 983-993 ◽

Cited By ~ 36

Author(s):

Sandra N.D. Hawthorne ◽

Patrick N.J. Lane ◽

Leon J. Bren ◽

Neil C. Sims

Keyword(s):

Vegetation Structure ◽

Water Yield ◽

Long Term Effects

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Long-Term Effects of Periodical Fires on Archaeal Communities from Brazilian Cerrado Soils

Archaea ◽

10.1155/2019/6957210 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

Aline Belmok ◽

Thiago Rodrigues-Oliveira ◽

Fabyano A. C. Lopes ◽

Heloisa S. Miranda ◽

Ricardo H. Krüger ◽

...

Keyword(s):

16S Rrna ◽

Vegetation Structure ◽

Archaeal Community ◽

Fire Frequency ◽

Sensu Stricto ◽

Burned Area ◽

Long Term Effects ◽

Terrestrial Environments ◽

Archaeal Communities

The Cerrado biome corresponds to an extensive area of Brazil and is considered a biodiversity hotspot. Frequent fires are a natural feature in this biome and have influences on vegetation structure and composition. However, continuous anthropogenic actions are promoting changes in fire frequency and seasonality. Despite the high biodiversity of the Cerrado, little is known about its microbiome, with few publications describing some aspects of the bacterial and fungal communities found on this biome and almost no references about archaea. In this study, we describe the archaeal diversity in Cerradosensu strictosoils, comparing the archaeal communities from soils of an area long protected from fires to one exposed to biennial fires, using both 16S rRNA andamoAgenes as molecular markers. Almost all 16S rRNA sequences from both studied areas were affiliated with I.1b and 1.1cThaumarchaeota, groups commonly detected in terrestrial environments. A higher relative abundance of I.1b thaumarchaeal subgroup was detected in the frequently burned area even though no statistically significant differences were observed in archaeal 16S rRNA richness and diversity between the investigated areas. Many ammonia-oxidizing archaea (AOA) are affiliated with this group, which is consistent with the higheramoAdiversity and OTU numbers detected in the area periodically burned. Taken together, our results suggest that, although total archaeal community richness and diversity do not seem to greatly differ between the investigated conditions, alterations in wood cover and vegetation structure caused by frequent fires likely cause long-term effects in AOA diversity in Cerrado soils.

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The short- and long-term effects of changes of vegetation structure on isopod (Oniscidea) diversity and composition in Mátra Mountains

Acta Universitatis Sapientiae Agriculture and Environment ◽

10.1515/ausae-2017-0012 ◽

2017 ◽

Vol 9 (1) ◽

pp. 127-139

Author(s):

Diána Vona-Túri ◽

Tünde Szmatona-Túri

Keyword(s):

Species Richness ◽

Vegetation Structure ◽

Regional Scale ◽

Natura 2000 ◽

Long Term Effects ◽

Short Term ◽

Negative Effect ◽

Protection Area ◽

Short And Long Term

Abstract The aim of the present study was to examine the short- and long-term effects of changes in vegetation structure caused by shrub removal and mowing on isopod diversity and composition in Natura 2000 habitats of Mátra Landscape Protection Area. Species richness and isopod diversity increased in the short term as a result of annual changes in vegetation; however, the values of both indices were reduced in the long term. The changes in vegetation structure on a regional scale led to a reduced isopod diversity in the short and long term. The changes in vegetation structure caused alterations in community structure in the long term. We conclude that changes of vegetation structure have a negative effect on species richness and the diversity of isopod communities in the long term.

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Vegetation Structure in Shahbazgari, District Mardan

International Letters of Natural Sciences ◽

10.18052/www.scipress.com/ilns.39.40 ◽

2015 ◽

Vol 39 ◽

pp. 40-48

Author(s):

Musharaf Khan ◽

Farrukh Hussain ◽

Shahana Musharaf

Keyword(s):

Calcium Carbonate ◽

Plant Species ◽

Soil Ph ◽

Vegetation Cover ◽

Vegetation Structure ◽

Research Area

The present work was made to investigate the vegetation structure of shrubs and herbs in research area. Total 48 plant species consisting of 7 shrubs and 41 herbs constructing Cenchrus-Zizyphus-Saccharum community from 9 sites in which 9 communities i.e. Fumaria-Rumex-Xanthium community, Cynodon-Solanum-Sonchus community, Cynodon-Sorghum-Alhagi community, Ajuga-Malvastrum-Calotropis community, Cynodon –Convolvulus-Cyperus community, Ajuga-Saccharum-Chenopodium community, Alhagi-Rumex-Euphorbia community, Saccharum-Cannabis-Xanthium community and Achyranthus-Ajuga-Euphorbia community were found. The contribution of total important values by shrubs was 43.78 and 256.2 by herbs. The soil of the area had better calcium carbonate in the range of (11.72 – 12.99 %), with soil pH (6.45 – 8.11). The EC was found in the range of (0.13-0.22 dS m-1). The concentrations of P and K content were found in the range of (3.54-3.92 mg Kg-1) and (111.21-127.14 mg Kg-1). These results highlight the constant need for long-term ground-based conservation monitoring in combination with satellite-based monitoring of changes in vegetation cover.

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Changes of Understory Vegetation Structure for 10 Years in Long-Term Ecological Research Site at Mt. Gyebang

Journal of Korean Forestry Society ◽

10.14578/jkfs.2014.103.1.1 ◽

2014 ◽

Vol 103 (1) ◽

pp. 1-11 ◽

Cited By ~ 6

Author(s):

Kwang Il Cheon ◽

Jung Hwa Chun ◽

Hee Mun Yang ◽

Jong Hwan Lim ◽

Joon Hwan Shin

Keyword(s):

Vegetation Structure ◽

Understory Vegetation ◽

Ecological Research ◽

Research Site ◽

Long Term Ecological Research

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Peatland fragments of southern Quebec: recent evolution of their vegetation structure

Canadian Journal of Botany ◽

10.1139/b99-186 ◽

2000 ◽

Vol 78 (2) ◽

pp. 255-265 ◽

Cited By ~ 12

Author(s):

Stéphanie Pellerin ◽

Claude Lavoie

Keyword(s):

Vegetation Structure ◽

Animal Species ◽

Ecological Integrity ◽

Geographical Information ◽

Peat Mining ◽

Long Period ◽

Forest Sites ◽

Environmental Agencies ◽

Natural Reserves

One of the main problems associated with small natural reserves is their progressive loss of ecological integrity owing to the influence of surrounding human activities. In southern Quebec (Bas-Saint-Laurent, Canada), peatlands are extensively mined to extract peat for the production of horticultural compost and are isolated within agricultural lands. Government environmental agencies have proposed that peat industries set aside 5-10% of a bog's area as a natural refuge for peatland plants and animals. Do these fragments constitute reliable refuges? Do they maintain their ecological characteristics over a long period? We studied the recent evolution of plant communities in peatland fragments using paleoecological techniques and a geographical information system. In the study area, some treeless fragments dominated by Sphagnum species have recently (since 1940) converted to forest sites. Macrofossil and dendrochronological analyses suggest that peat-mining activities were not the main factors responsible for the afforestation of peatland fragments. On the other hand, the isolation of the Bas-Saint-Laurent peatlands within an agricultural plain for more than 100 years may explain the afforestation process (drainage activities). Furthermore, fires may have accelerated afforestation by facilitating the spread of seeds of tree species with serotinous cones. Because most peatlands of the Bas-Saint-Laurent region are still affected by drainage and fires, it is probable that several open bog fragments will not maintain their treeless vegetation structure over a long period. Consequently, peatland fragments should not be considered as a solution to long-term conservation needs in southern Quebec, at least not for plant and animal species of open bogs. This study also shows that even ecosystems known to be resistant to invasions by exotic species (such as peatlands) can be strongly affected by fragmentation and by their surrounding environment on a long-term basis.Key words: peatland, peat mining, fire, fragmentation, conservation, Quebec.

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Long-term changes in size and composition of seed bank during succession: from meadow to forest

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1998.039 ◽

2014 ◽

Vol 67 (3-4) ◽

pp. 301-311 ◽

Cited By ~ 10

Author(s):

Krystyna Falińska

Keyword(s):

Seed Bank ◽

Vegetation Structure ◽

Canopy Structure ◽

Spatial Dynamics ◽

Floristic Composition ◽

Perennial Herb ◽

Mirror Reflection ◽

Seed Migration ◽

Initial Stage

Studies of the relation between the size and floristic composition of the seed bank and the vegetation during succession were conducted in the years 1976-1996. The results of the research did not confirm the hypothesis of directional changes in the density of seeds as the observed changes were of fluctuating nature. At the start of succession the seed bank was small (2970 seeds/m2), and in subsequent years the density of seeds increased successively to reach the highest level after 15 years (9170/m2 ), then dropped again. After 20 years the density of seeds reached the value recorded at the initial stage (2468/m2). Successional changes in floristic richness of seed bank were directional with the number of species falling from 52 to 24. All data indicate that the floristic composition of the seed bank is not a mirror reflection of the vegetation structure, but rather a record of a long-term turnover of species and many different events which in various periods of time influenced the inflow of seeds to the soil (spatial dynamics of the necromass, perennial herb and willow canopy structure, seed migration).

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