Contrasting Soil Ciliate Species Richness and Abundance between Two Tropical Plant Species: A Test of the Plant Effect

A continuing challenge in orthopteran ecology is to understand what determines grasshopper species diversity at a given site. In this study, the objective was to determine if variation in grasshopper abundance and diversity between 23 sites in western North Dakota (USA) could be explained by variation in plant species richness and diversity. In this system with relatively low plant diversity, grasshopper species richness and abundance were not significantly associated with plant species richness in either year. Although a number of significant associations between plant diversity and grasshopper diversity were found through regression analyses, results differed greatly between years indicating that plant species richness and diversity did not lead to strong effects on grasshopper diversity metrics. Plant species richness appears to be too coarse grained to lead to accurate predictions of grasshopper species richness in this system dominated by generalist grasshopper species.

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Area modulates the effect of elevation but not of land use or canopy on tropical plant species richness

Biodiversity and Conservation ◽

10.1007/s10531-021-02304-6 ◽

2021 ◽

Author(s):

Andreas Hemp ◽

Corina Del Fabbro ◽

Markus Fischer

Keyword(s):

Land Use ◽

Species Richness ◽

Tropical Forests ◽

Plant Species ◽

Habitat Type ◽

Plant Species Richness ◽

Tropical Regions ◽

Tropical Plant ◽

Set Up ◽

Elevational Range

AbstractOne of the few general patterns in ecology is the increase of species richness with area. However, factors driving species-area relationship (SAR) are under debate, and the role of human-induced changes has been overlooked so far. Furthermore, SAR studies in tropical regions, in particular in multilayered rain forests are scarce. On the other side, studies of global change-induced impacts on biodiversity have become increasingly important, particular in the tropics, where these impacts are especially pronounced. Here, we investigated if area modulates the effect of land use, elevation and canopy on plant species richness. For the first time we studied SAR in multilayered tropical forests considering all functional groups. We selected 13 natural and disturbed habitats on Kilimanjaro in Tanzania, distributed over an elevational range of 3700 m. In each habitat type, we set up three to six modified Whittaker plots. We recorded all plant species in 64 plots and 640 subplots and described SAR using the power function. Area consistently modulated effects of elevation on plant species richness, partly effects of land use but not effects of plant canopy. Thus, area needs to be taken into account when studying elevational plant species richness patterns. In contrast to temperate regions open and forest habitats did not differ in SAR, probably due to a distinct vertical vegetation zonation in tropical forests. Therefore, it is important to consider all vegetation layers including epiphytes when studying SAR in highly structured tropical regions.

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Impact of Mikania micrantha H.B.K. Invasion on Diversity and Abundance of Plant Species of Chitwan National Park, Nepal

Journal of Institute of Science and Technology ◽

10.3126/jist.v19i2.13849 ◽

2015 ◽

Vol 19 (2) ◽

pp. 30-36 ◽

Cited By ~ 2

Author(s):

Binoj Kumar Shrestha ◽

Dharma Raj Dangol

Keyword(s):

Species Richness ◽

Plant Species ◽

National Park ◽

Sampling Technique ◽

Plant Species Richness ◽

Alien Plant ◽

Mikania Micrantha ◽

Crown Cover ◽

Chitwan National Park ◽

Species Richness And Abundance

This research investigated the invasion of the alien plant Mikania micrantha H.B.K. and its impact on plant species richness and abundance in Chitwan National Park (CNP) forest. Stratified sampling technique was used to collect the information using the nested quadrats in the Mikania invaded and not invaded sites in July 2011. The study revealed that the invasion highly related with the vegetation structure of the habitat; higher the tree crown cover lower the invasion. On the other hand, the invasion in terms of cover percent of Mikania irrespective of the biomass (fresh weight) decreased plant species richness. Species richness showed unimodal response to the Mikania cover percent with the decrease after 35% of Mikania cover. Journal of Institute of Science and Technology, 2014, 19(2): 30-36

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Influence of field margin type on weed species richness and abundance in conventional crop fields

Renewable Agriculture and Food Systems ◽

10.1017/s1742170510000451 ◽

2010 ◽

Vol 26 (2) ◽

pp. 127-136 ◽

Cited By ~ 4

Author(s):

S.C. Reberg-Horton ◽

J.P. Mueller ◽

S.J. Mellage ◽

N.G. Creamer ◽

C. Brownie ◽

...

Keyword(s):

Species Richness ◽

Plant Species ◽

Field Margins ◽

Weed Species ◽

Field Margin ◽

Crop Fields ◽

Crop Field ◽

Field Edge ◽

Species Richness And Abundance ◽

Weed Species Richness

AbstractNatural vegetation occurring on farms in field margins, fallow fields, ditch systems and neighboring forests, provides increased biodiversity, structural diversity, habitat for wildlife and beneficial insects, and can act as a protective buffer against agrochemical drift. Nevertheless, farmers frequently view these areas as non-productive and as potential sources of weeds, insect pests and diseases. Weed species richness and abundance were examined in crop fields in 2002–2003 at the Center for Environmental Farming Systems near Goldsboro, NC to determine if crop field weed infestation was associated with field margin management (managed versus unmanaged). Weed species abundance and richness were measured over two growing seasons on four occasions in crop fields along permanent transects that extended from the field edge toward the center of the field. The presence/absence of data for all plant species in the field margin was also recorded. For both margin types, managed and unmanaged, more weeds were found near the field edge than in the center of the field. Weed species richness was slightly higher in cropland bordering managed margins than in cropland along unmanaged margins. Several significant interactions led to an examination of nine dominant weed species in each field margin type and their distribution in crop fields. When all sampling dates were pooled, only 42 (40%) of 105 species identified in the field margins were observed in the crop field. Managed margins had lower species richness than unmanaged field margins—less than half the mean number of species (15 versus 6 species, respectively). Contingency table analysis did not reveal any association between plant species occurring in the margin and those found in the crop field. Furthermore, margin type and weed presence in the field margin were not effective predictors of weed occurrence in the crop field as determined by logistic regression.

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Effects of size, shape, and edge on vegetation in remnants of the upland boreal mixed-wood forest in agro-environments of Alberta, Canada

Canadian Journal of Botany ◽

10.1139/b07-018 ◽

2007 ◽

Vol 85 (3) ◽

pp. 273-284 ◽

Cited By ~ 14

Author(s):

L. Dennis Gignac ◽

Mark R.T. Dale

Keyword(s):

Species Richness ◽

Alien Species ◽

Plant Species ◽

Fragment Size ◽

Vascular Plant ◽

Plant Species Richness ◽

Percent Cover ◽

Shrub Species ◽

Alien Plant ◽

Species Richness And Abundance

Forty-one remnants of the aspen-dominated upland forest in three subregions of the dry boreal mixed-wood in Alberta were studied to determine effects of fragment size and shape on native and alien plant species richness and abundance in agro-environments. The percent cover of all vascular plant species was visually estimated in 5 m diameter circular plots along transects that covered the length and the width of each fragment. A subset of 12 of the largest fragments (>900 m2) that had distinct interiors (portions of the fragment >15 m from any edge) was used to measure edge effects on the vegetation. Regression analyses revealed significant positive relationships between species richness and area regardless of the subregion. Species richness stabilized in fragments that were larger than 11 ha. Edges did not affect shrub species richness and only affected herbaceous species richness on west- and south-facing aspects. Shrub abundance decreased and herb abundance increased up to 20 m from the edges regardless of orientation. Edges did not support a different suite of species than interiors, although several species occurred more frequently in the interior than along the edges. Alien species richness and abundance reached their highest values between 5 and 15 m from the edge, and some of those species could be found up to 40 m from the edge. Although larger fragments generally supported more alien species than smaller fragments, the smallest fragments had the greatest number of species per metre squared. Results from this study indicated that it would be preferable to conserve larger woodlots rather then several smaller woodlots on the landscape.

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Plant species richness and abundance in residential yards across a tropical watershed: implications for urban sustainability

Ecology and Society ◽

10.5751/es-06164-190322 ◽

2014 ◽

Vol 19 (3) ◽

Cited By ~ 17

Author(s):

Cristina P. Vila-Ruiz ◽

Elvia Meléndez-Ackerman ◽

Raul Santiago-Bartolomei ◽

Diana Garcia-Montiel ◽

Lourdes Lastra ◽

...

Keyword(s):

Species Richness ◽

Plant Species ◽

Urban Sustainability ◽

Plant Species Richness ◽

Residential Yards ◽

Species Richness And Abundance ◽

Tropical Watershed

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Corrigendum to: Impacts of level of utilisation by grazing on an Astrebla (Mitchell grass) grassland in north-western Queensland between 1984 and 2010. 2. Plant species richness and abundance

The Rangeland Journal ◽

10.1071/rj11069_co ◽

2014 ◽

Vol 36 (3) ◽

pp. 309

Author(s):

D. M. Orr ◽

D. G. Phelps

Keyword(s):

Species Richness ◽

Plant Species ◽

Plant Species Richness ◽

Seasonal Rainfall ◽

Yearly Variation ◽

Rainfall Variation ◽

Species Richness And Abundance ◽

North Western ◽

Sampling Times

The occurrence of interstitial species in Astrebla grasslands in Australia are influenced by grazing and seasonal rainfall but the interactions of these two influences are complex. This paper describes three studies aimed at determining and explaining the changes in plant species richness and abundance of the interstitial species in a long-term sheep utilisation experiment in an Astrebla grassland in northern Queensland. In the first study, increasing utilisation increased the frequency of Dactyloctenium radulans (Button grass) and Brachyachne convergens (Downs couch) and reduced that of Streptoglossa adscendens (Mint bush). In the second study, seasonal rainfall variation between 1984 and 2009 resulted in large annual differences in the size of the seed banks of many species, but increasing utilisation consistently reduced the seed bank of species such as Astrebla spp. and S. adscendens and increased that of species such as B. convergens, D. radulans, Amaranthus mitchellii (Boggabri) and Boerhavia sp. (Tar vine). In the third study, the highest species richness occurred at the lightest utilisation because of the presence of a range of palatable forbs, especially legumes. Species richness was reduced as utilisation increased. Species richness in the grazing exclosure was low and similar to that at the heaviest utilisation where there was a reduction in the presence of palatable forb species. The pattern of highest species richness at the lightest grazing treatment was maintained across three sampling times, even with different amounts of seasonal rainfall, but there was a large yearly variation in both the density and frequency of many species. It was concluded that the maintenance of highest species richness at the lightest utilisation was not aligned with other data from this grazing experiment which indicated that the maximum sustainable wool production occurred at moderate utilisation.

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