Threatened dry grasslands in the continental boreal forests of Wood Buffalo National Park

1997 ◽  
Vol 75 (8) ◽  
pp. 1363-1370 ◽  
Author(s):  
A. G. Schwarz ◽  
Ross W. Wein

Dry grasslands in Wood Buffalo National Park are unique biological features at 60°N latitude, since they contain plant species normally found in more southern grasslands at 50–55°N latitude. The objectives of this study were to inventory dry grasslands, classify them according to similarity of species cover, and establish relationships with understory species in Populus tremuloides and shrub communities. Dry grasslands were studied at nine sites; most were clustered in the Salt River and Peace Point areas. The largest unit of grassland was about 3.0 ha, and most units were less than 0.5 ha. This contrasts with the hundreds of hectares recorded earlier in the century. Of the 128 vascular plant species identified, 29 are considered as southern, and of these, 15 are regionally rare. Sixty-four plots were classified into nine community types, using two-way indicator species analysis. A group of six communities were dominated by grass and shrub species with a component of southern grassland species. Three communities, strongly dominated by Populus and shrubs, represent community types that invade dry grasslands. Ordination of plots using detrended correspondence analysis showed relationships among the community types and a clear separation of southern grassland species from those found in forest communities. Vascular plant diversity, as represented by mean species richness, ranged from about 15 to 28, and Shannon diversity indices ranged from 1.883 to 2.615. The cover of southern grassland species was negatively correlated (correlation coefficient of −0.524) with cover of tall shrubs and trees, suggesting that the dry grasslands of Wood Buffalo National Park are threatened by tree and shrub invasion, which is due, in part, to a lack of recent fires at these sites. Key words: northern grasslands, biodiversity, endangered species, endangered spaces.

1999 ◽  
Vol 77 (7) ◽  
pp. 918-921
Author(s):  
A G Schwarz ◽  
Ross W Wein

In examining dry grassland areas of Wood Buffalo National Park (WBNP), we used vascular plant indicators commonly found in the grassland landscapes in the southern and central parts of the Prairie Provinces. With distance northward the landscapes become increasingly tree-dominated and the dry grasslands have fewer dry grassland indicator species (about 40 in the area of WBNP) and become smaller in size (about 1 ha in WBNP). Key species are Stipa comata Trin & Rupr., Stipa curtiseta (A.S. Hitchc.) Barkworth, and Stipa columbiana Macoun on the drier sites. Paleontological records and historical documents suggest that these remnant dry grasslands must expand during decades of drought and must contract during decades of higher summer rainfall. We hypothesize that fires might enhance dry grassland expansion by stressing and killing trees and shrubs. Southern dry grassland vascular plant species represent over 7% of the total in WBNP. It is reasonable to hypothesize that these represent special ecotypes that deserve special protection through prescribed burning.Key words: remnant grasslands, Stipa spp., climate change.


1989 ◽  
Vol 67 (4) ◽  
pp. 1126-1136 ◽  
Author(s):  
M. Muc ◽  
B. Freedman ◽  
J. Svoboda

A cluster analysis was used to apportion 136 stands in a High Arctic lowland among six vascular plant community types. These communities are described on the basis of the average prominence values of vascular species and the total cover of macroalgae, bryophytes, lichens, and vascular plants within the designated clusters of stands. The relationships among the community types was explored by a detrended correspondence analysis. The ordination of stands showed considerable floristic overlap among the most widespread plant communities on the lowland. This largely reflects the microtopographic heterogeneity of the sites, the relatively depauperate flora of the High Arctic, and the considerable ecological amplitude of the most prominent vascular plant species.


1992 ◽  
Vol 70 (3) ◽  
pp. 614-628 ◽  
Author(s):  
George H. La Roi

Sixty-five undisturbed stands, spanning a wide range of physical habitats in the southern boreal subzone, were sampled in central Alberta using relevés, then classified with two-way indicator species analysis (TWINSPAN) and ordinated with detrended correspondence analysis (DECORANA), based on the estimated midsummer percent cover of 100 vascular plant species. Six floristically and ecologically distinct community types were recognized along soil-moisture and texture–nutrient gradients: oligotrophic PINUS BANKSIANA/ASTER LAEVIS on warm, xeromesic, nutrient-poor sand deposits; oligo-mesotrophic PINUS BANKSIANA/CORNUS CANADENSIS on cooler, xeromesic to submesic, low-nutrient sands; mesotrophic PICEA GLAUCA – POPULUS TREMULOIDES/ELYMUS INNOVATUS on mesic, medium-nutrient tills; eu-mesotrophic PICEA GLAUCA – POPULUS TREMULOIDES/RIBES TRISTE on mesic to hygromesic, nutrient-rich alluvium and till; oligotrophic PICEA MARIANA/RUBUS CHAMAEMORUS on cool, hygromesic to hygric, nutrient-poor peatlands; oligotrophic PICEA MARIANA/CAREX AQUATILIS on hygric to hydric, low-nutrient peatlands. The six community types and 19 species groups elucidated by TWINSPAN occupy distinct sectors on the two-dimensional DECORANA ordination that are associated with differences in moisture and nutrient availability. The community types are ecologically vicarious with boreal forest assemblages previously described for Alaska, central and eastern Canada, and northwestern Europe. Key words: cover, ecological series, gradient, moisture, nutrients, plant community, soil, vascular plant species, vegetation.


2016 ◽  
Vol 5 (1) ◽  
pp. 29-45 ◽  
Author(s):  
Md Anwarul Islam ◽  
Mohammad Mahfuzur Rahman ◽  
Gazi Mosharof Hossain

The present study dealt with the exploration and documentation of the floristic composition and phyto-diversity of Sitakunda Eco-park, Chittagong, Bangladesh. A total of 412 vascular plant species under 315 genera belonging to 94 plant families have been recorded from the study area during February, 2013 to April, 2015. Out of these recorded taxa, 330 were dicotyledons, 62 were monocotyledons, 5 were gymnosperms and 15 were pteridophytes. Among those, the maximum 144 species belonged to herbs followed by 138, 75 and 55 species as trees, shrubs and climbers, respectively. The species composition among the plant families varied in plant groups. In dicotyledonous group, Euphorbiaceae appeared to be the largest family with 35 species, whereas Poaceae showed the largest family containing 30 species among monocotyledonous group. The highest values of both Shannon-Weiner and Simpson diversity indices have been observed as 3.82 and 0.98, respectively to site D during monsoon season, whereas the lowest values 3.19 and 0.95, respectively of these indices were recorded in site A during summer season.Jahangirnagar University J. Biol. Sci. 5(1): 29-45, 2016 (June)


2002 ◽  
Vol 32 (7) ◽  
pp. 1180-1191 ◽  
Author(s):  
F Wayne Bell ◽  
Steven G Newmaster

The practice of clear-cutting, followed by site preparing with mechanical equipment, planting a single tree species, and applying herbicides, has recently been cited as a procedure that creates monocultures in northern forests. Research on a trembling aspen (Populus tremuloides Michx.) dominated mixedwood provided an opportunity to examine the potential of silvicultural activities to (i) create monocultures, (ii) create opportunities for the establishment of exotic plant species, and (iii) result in the loss of indigenous plant species. Detailed botanical surveys were conducted for up to 5 years post-treatment in four clearcuts that were mechanically site prepared, planted with a single conifer species, and released with either motor-manual, mechanical, or herbicide treatment. Species richness, abundance (foliar cover), diversity indices, and rank abundance diagrams indicate that the treatments had immediate effects, but none created a monoculture during the period of study. We conclude that the use of clear-cutting, mechanical site preparation, planting a single conifer species, followed by release with motor-manual cutting, mechanical cutting, or herbicide spraying, will not create monocultures in the conditions tested. While 37 exotic species were observed, none of them were tree or shrub species. In addition, no net loss of indigenous seed producing plants was detected. Missed strips and patches, which accounted for up to 25% of the sampled area, buffered treatment effects.


2015 ◽  
Vol 39 (1) ◽  
pp. 79-90
Author(s):  
Izabella Kirpluk ◽  
Anna Bomanowska

Abstract Studies aimed at the identification of the range and method of spread of alien plant species in settlement areas in Kampinos National Park (KNP) and its immediate vicinity were carried out in years 2012-2014. Special emphasis was put on surveying the sites of invasive alien species (IAS), and diagnosing potential threats posed to the natural and semi-natural vegetation of the national park by the IAS present in rural areas. We found 53 alien vascular plant species, including 40 invasive taxa which may potentially pose a threat to the ecosystems of KNP. Species encroaching from settlement areas to semi-natural and natural communities included: Bidens frondosa, Echinocystis lobata, Impatiens glandulifera, I. parviflora, Juncus tenuis, Lupinus polyphyllus, Reunoutria japonica and Solidago gigantea. Most of them were species from the highest invasiveness (IV and III) classes in Poland. Similarity analysis carried out for all investigated localities with regard to all alien species, and only for invasive ones showed a clear division into separate groups: villages within the boundaries of the national park and villages outside the park.


1999 ◽  
Vol 77 (7) ◽  
pp. 918-921
Author(s):  
A.G. Schwarz ◽  
Ross W. Wein

2016 ◽  
Vol 27 (3-4) ◽  
pp. 16-26
Author(s):  
B. A. Baranovski

Results of non-native flora surveys on Samara Dniprovska River valley within the designed National Park «Samarsky Bir» were analyzed in the paper. Scientific justification on first stage creation of the national-level National Park «Samarsky Bir» was prepared in 2012. Its area included the main park area with floodplain, arena and gully landscapes of the rivers Samara and Oril interstream. List of vascular plant species on floodplain, arena and gully habitats of Prisamar'ya counted 887 species. They are classified as 5 divisions, 6 classes, 108 families, 429 genera. This article presents a list of non-native flora fraction with bioecological characteristic of the plant species. The surveys were conducted by conventional methods on vascular flora studying. Analysis of the main plant ecomorphs was carried out by A. L. Belgard ecomorph system (1950). Invasion of plant species in the steppe zone of Ukraine has a long history complicated by significant anthropogenic transformation of the territory. We investigated the status of non-native plants, their ecomorphs, and tendency to invasiveness on the territory of National Park «Samarsky Bir» designed. Presence of 195 adventitious vascular plant species belonging to 48 families was determined. Of them, 7 families with the greatest abundance of non-native species contained 113 taxa (58 % of the total); 20 families were represented with 2–7 advents, and 20 families contained only 1 non-native species. Thus, today the share of non-native species in the vascular flora of the region accounted for nearly 22 %. Most of adventitious species are mesoxerophytes and xeromesophytes. In a cenomorphic relationship, vegetation being ruderal on the territory of Ukraine is dominated in composition of non-native flora. Within the total number of adventitious species, archaeophytes amount up 44 %, whereas neophytes come up to 56 %. The greatest abundance of adventitious species has been found in Brassicaceae, Asterasea and Poaceae families (15 %, 12 %, and 11 % of the total, respectively). 119 non-native vascular plant species were found in the steppe cenoses, 79 species in the gully and watershed forests, 90 species in floodplain forests, and 52 species on the territory of the sandy terrace. Among all the non-native species, 28 species have been identified as invasive, and there was a trend to increased invasiveness of some species in recent years. Among heterogenous species 12 of them were identified as invasive, and there was a tendency to increase theinvasiveness of some species in recent years. The analysis provided on non-native flora in the National Park evidences significant anthropogenic transformation of the territory; that requires establishment of appropriate regime on protection of this important ecological object.


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