Fire and drought experiments in northern wetlands: a climate change analogue

1991 ◽  
Vol 69 (9) ◽  
pp. 1991-1997 ◽  
Author(s):  
John C. Hogenbirk ◽  
Ross W. Wein
Keyword(s):  
Climate Change ◽  
Native Species ◽  
Plant Cover ◽  
Stem Density ◽  
Percent Cover ◽  
Drought Treatment ◽  
Vegetation Zone ◽  
Vegetation Zones ◽  
Seasonally Flooded ◽  
Eurasian Species

Drought and fire, which may increase in frequency and severity because of global warming, were simulated in mid-boreal wetlands by transplanting soil blocks upslope to a lower water table and by prescribed burns. In the 2 years after treatments were applied to seasonally flooded vegetation zones in the Peace–Athabasca Delta, Alberta, the drought treatment did not significantly change stem density and height of the dominant hygrophytes Calamagrostis canadensis and Carex atherodes. Dicotyledonous species' density and richness increased 3- to 36-fold on soil blocks moved upslope to the driest vegetation zone relative to unmoved soil blocks. The percent cover of native dicotyledonous species was unaffected but that of xerophytic Eurasian species, Sonchus arvensis and Cirsium arvense, increased 5- to 13-fold after drought treatment. Fire, particularly the deepest burn, reduced graminoid density and height up to 90%. Dicotyledon density, but not richness, was generally higher after fire. Plant cover was unaffected by fire but Eurasian species' cover was still 3- to 15-fold greater than that of native species. Seasonally flooded vegetation zones will likely be shifted from flood-driven dynamics with cool and moist environmental conditions towards drought- and fire-driven dynamics with warmer and drier conditions. It is hypothesized that, under these climate change conditions, Eurasian species might dominate early successional communities in mid-boreal wetlands. Key words: drought, fire, greenhouse effect, Peace–Athabasca Delta, wetland vegetation, Wood Buffalo National Park.

Recreational Changes in the Forest Ecosystem Components: Case Study of the Cultural Heritage Site “White Sea Petroglyphs” (Republic of Karelia)

2020 ◽  
pp. 90-105
Author(s):  
A.V. Tuyunen ◽  
◽  
V.V. Timofeeva ◽  
A.Yu. Karpechko ◽  
Y.N. Tkachenko ◽  
...  
Keyword(s):  
Native Species ◽  
White Sea ◽  
Plant Cover ◽  
Ground Cover ◽  
Tree Seedlings ◽  
Percent Cover ◽  
Tree Stand ◽  
Rock Outcrops ◽  
Heritage Site ◽  
Recreation Impact

Recreation digression of forest ecosystems in the heritage site “White Sea Petroglyphs” was studied for the first time. This site is a compact system of rock outcrops partially cleared of forest vegetation, which bear Neolithic rock carvings (petroglyphs), and are linked together by walking trails. Patterns have been identified in the transformation of soils, plant cover components (tree stand, tree seedlings, understory and living ground cover), as well as fine roots (within 3 mm in diameter) of woody species under the recreation impact. Trampling was found to deform and destroy the top soil horizons, entailing a significant loss of the forest floor thickness and organic matter stores. Overall, the flora of the area is quite well preserved; 95–100 % of which is represented by native species. The living ground cover is noticeably damaged in the most actively used sites (fragments of trails and vista points). They feature a poor species composition, shrinking of the herb-dwarf shrub and moss-lichen cover, and a low percent cover of grassland and ruderal species. Easily accessible and actively visited sites have no or reducing amounts of tree seedlings, the tree stand is damaged and forest regeneration is hampered – the number of viable seedlings is minimal (100 pcs/ha). The mass of roots below 3 mm in diameter in heavily trampled trails showed a reduction of up to 74 %, while the root saturation in less affected trails slightly increased. Recreation transformations of the plant communities have not resulted in a loss of their resilience so far. The recreational digression in the studied sites was classified into stages I–III (weakly disturbed – strongly disturbed). Function zoning of the area should be modified using recreation-tolerant communities more intensively in order to reduce recreation impact. The most damaged areas, which are losing their stability, should be excluded from active use by modification of walking trails and building additional boardwalks.

Salt marsh width positively affects the occurrence of Least and Pectoral Sandpipers in the St. Lawrence River Estuary during fall migration

2021 ◽  
Vol 135 (2) ◽  
pp. 192-202
Author(s):  
Yves Turcotte ◽  
Jean-François Lamarre ◽  
Éliane Duchesne ◽  
Joël Bêty
Keyword(s):  
Climate Change ◽  
Salt Marsh ◽  
Salt Marshes ◽  
Generalized Estimating Equations ◽  
River Estuary ◽  
Effective Management ◽  
Vegetation Zone ◽  
Vegetation Zones ◽  
Coastal Squeeze ◽  
St Lawrence River

Salt marshes are vulnerable to climate change-associated sea-level rise and storm-induced surges. Their degradation will likely affect shorebirds relying on this ecosystem. Least Sandpiper (Calidris minutilla) and Pectoral Sandpiper (Calidris melanotos) migrating along coastline habitats typically use salt marshes to rest and replenish their body reserves. Our objective was to test if width of the different vegetation zones within salt marshes affects the occurrence of Least and Pectoral Sandpipers stopping along the St. Lawrence River Estuary, Quebec, Canada, during fall migration. We established 26 survey sites, each 600 m in length, along the shoreline. Shorebird surveys were conducted in 2011 and 2012. We characterized salt marshes by measuring the width of each vegetation zone (lower marsh and upper marsh). We analyzed shorebird presence/not detected data with generalized estimating equations to test the predictions that occurrence of Least Sandpipers and Pectoral Sandpipers increases with width of both the lower and upper marsh. Upper marsh width was positively associated with probability of occurrence in each species. Our results highlight the importance of protecting the integrity of salt marshes for these two species. In the St. Lawrence River Estuary, where landward migration of salt marshes is no longer possible (coastal squeeze), effective management of shorelines is much needed. Otherwise, salt marshes and these two species could be locally jeopardized.

Regional biogeographical model of vegetation zones in doctoral programme Regional Biography in Olomouc (Case study for Norway spruce)

2020 ◽  
Author(s):  
Ivo Machar ◽  
Marián Halás ◽  
Zdeněk Opršal
Keyword(s):  
Climate Change ◽  
Regional Climate ◽  
Climate Change Impacts ◽  
Climate Data ◽  
Ecological Data ◽  
The Czech Republic ◽  
Climate Conditions ◽  
Vegetation Zones ◽  
Landscape Research

Regional climate changes impacts induce vegetation zones shift to higher altitudes in temperate landscape. This paper deals with applying of regional biogeography model of climate conditions for vegetation zones in Czechia to doctoral programme Regional Geography in Palacky University Olomouc. The model is based on general knowledge of landscape vegetation zonation. Climate data for model come from predicted validated climate database under RCP8.5 scenario since 2100. Ecological data are included in the Biogeography Register database (geobiocoenological data related to landscape for cadastral areas of the Czech Republic). Mathematical principles of modelling are based on set of software solutions with GIS. Students use the model in the frame of the course “Special Approaches to Landscape Research” not only for regional scenarios climate change impacts in landscape scale, but also for assessment of climate conditions for growing capability of agricultural crops or forest trees under climate change on regional level.

scholarly journals RESTORATION OF FORMER GRASSLAND IN SOUTH-CENTRAL TEXAS

2019 ◽  
Vol 71 (1) ◽  
Author(s):  
Wendy J. Leonard ◽  
O. W. Van Auken
Keyword(s):  
San Antonio ◽  
Plant Cover ◽  
Woody Species ◽  
Bare Soil ◽  
Grass Species ◽  
Herbaceous Plant ◽  
Percent Cover ◽  
Juniperus Ashei ◽  
South Central ◽  
Central Texas

Abstract In the past, grasslands and savannas were common in many areas of south-central Texas, including the San Antonio area. With the advent of European settlers and their livestock, much of this area was converted to agriculture and rangeland. Today, most of San Antonio is developed, but some preservation has occurred. Restored grassland, mechanically cleared of Juniperus ashei (juniper, Ashe juniper) and other woody species in 2013, was examined and compared to adjacent non-cleared woodland. The woodland examined was dominated by Diospyros texana (Texas persimmon) and Juniperus ashei. Richness in the woodland canopy was 15 species. The understory below the canopy had 25 woody species. In the restored grassland area, herbaceous plant cover was 41.8%, woody plant cover 5.8%, bare soil 2.9%, and litter cover 49.5%. Species richness was 71, with 60 herbaceous and 11 woody species (percent cover of each from <0.1–7.1%). The most common species in the restored grassland in descending order were Nassella leucotricha (Texas winter grass), Calyptocarpus vialis (straggler daisy), Carex planostachys (cedar sedge), Sporobolus crypandrus (sand dropseed), D. texana, and Verbesina virginica (frost weed). Several C4 grass species were present with low cover but may increase in abundance over time. Four of the six most common restored grassland species were present below the woodland canopy and 12 woody species were present in the restored grassland as juveniles. Cost of restoration was approximately $38,500 ($7,500 supplies, $31,000 labor).

scholarly journals Predicting Current Potential Distribution and the Range Dynamics of Pomacea canaliculata in China under Global Climate Change

Biology ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 110
Author(s):  
Yingxuan Yin ◽  
Qing He ◽  
Xiaowen Pan ◽  
Qiyong Liu ◽  
Yinjuan Wu ◽  
...  
Keyword(s):  
Climate Change ◽  
Native Species ◽  
Potential Distribution ◽  
Global Climate ◽  
Social Economy ◽  
Maximum Temperature ◽  
Pomacea Canaliculata ◽  
Climate Conditions ◽  
Jackknife Test ◽  
Recent Climate

Pomacea canaliculata is one of the 100 worst invasive alien species in the world, which has significant effects and harm to native species, ecological environment, human health, and social economy. Climate change is one of the major causes of species range shifts. With recent climate change, the distribution of P. canaliculata has shifted northward. Understanding the potential distribution under current and future climate conditions will aid in the management of the risk of its invasion and spread. Here, we used species distribution modeling (SDM) methods to predict the potential distribution of P. canaliculata in China, and the jackknife test was used to assess the importance of environmental variables for modeling. Our study found that precipitation of the warmest quarter and maximum temperature in the coldest months played important roles in the distribution of P. canaliculata. With global warming, there will be a trend of expansion and northward movement in the future. This study could provide recommendations for the management and prevention of snail invasion and expansion.

scholarly journals Riparian Vegetation Density Mapping of an Extremely Densely Vegetated Confined Floodplain

Hydrology ◽  
2021 ◽  
Vol 8 (4) ◽  
pp. 176
Author(s):  
István Fehérváry ◽  
Tímea Kiss
Keyword(s):  
Riparian Vegetation ◽  
Woody Species ◽  
Submerged Vegetation ◽  
Vegetation Types ◽  
Vegetation Density ◽  
Vegetation Zone ◽  
Density Mapping ◽  
Vegetation Zones ◽  
Branch Density ◽  
Vegetation Patches

The most crucial function of lowland-confined floodplains with low slopes is to support flood conveyance and fasten floods; however, obstacles can hinder it. The management of riparian vegetation is often neglected, though woody species increase the vegetation roughness of floodplains and increase flood levels. The aims are (1) to determine the branch density of various riparian vegetation types in the flood conveyance zone up to the level of artificial levees (up to 5 m), and (2) to assess the spatial distribution of densely vegetated patches. Applying a decision tree and machine learning, six vegetation types were identified with an accuracy of 83%. The vegetation density was determined within each type by applying the normalized relative point density (NRD) method. Besides, vegetation density was calculated in each submerged vegetation zone (1–2 m, 2–3 m, etc.). Thus, the obstacles for floods with various frequencies were mapped. In the study area, young poplar plantations offer the most favorable flood conveyance conditions, whereas invasive Amorpha thickets and the dense stands of native willow forests provide the worst conditions for flood conveyance. Dense and very dense vegetation patches are common in all submerged vegetation zones; thus, vegetation could heavily influence floods.

Change in Leafy Spurge (Euphorbia esula) Density and Soil Seedbank Composition 10 Years following Release of Aphthona spp. Biological Control Agents

2013 ◽  
Vol 6 (1) ◽  
pp. 147-160 ◽  
Author(s):  
Cassandra M. Setter ◽  
Rodney G. Lym
Keyword(s):  
Native Species ◽  
Kentucky Bluegrass ◽  
Leafy Spurge ◽  
Euphorbia Esula ◽  
Stem Density ◽  
Ecological Sites ◽  
Western North Dakota ◽  
Soil Seedbank ◽  
Weedy Species ◽  
Native Species Richness

AbstractFlea beetles (Aphthona spp.) were released in the Little Missouri National Grasslands (LMNG) in western North Dakota in 1999 to control leafy spurge. The changes in leafy spurge density and soil seedbank composition were evaluated on two ecological sites 10 yr (2009) after Aphthona spp. release to monitor the effectiveness of the insects on weed control and the associated changes in plant communities. In 2009, leafy spurge stem density averaged 2 and 9 stems m−2 (0.19 to 0.84 ft−2) in the loamy overflow and loamy sites, respectively, compared with 110 and 78 stems m−2, respectively, in 1999. Leafy spurge constituted nearly 67% of the loamy overflow seedbank in 1999, compared with 2% in 2009. In the loamy seedbank, the weed represented nearly 70% in 1999, compared with approximately 15% in 2009. As leafy spurge abundance was reduced, native species richness and seed count increased 10 yr after Aphthona spp. release. Late seral species represented 17% of the loamy overflow seedbank in 2009, an increase from 5% in 1999. However, Kentucky bluegrass, a nontarget weedy species, increased more than 250% in the loamy overflow seedbank. Late seral species were 38% of the loamy seedbank in 2009, compared with 13% in 1999. The number of native species increased from 31 in 1999 to 39 in 2009 in the loamy overflow seedbank, but only changed from 32 to 34 species in the loamy site during the same period. The reestablishment of native species has been slow, but seedbank analysis indicates the number and type of species found before the leafy spurge infestation have increased. Planting native species in selected areas may have reduced the lag time in these species return to the seedbank and reduced invasion from other nondesirable species, such as Kentucky bluegrass.

Bulbostylis litoreamazonicola, a new species of Cyperaceae from the Brazilian Amazonian coast

Phytotaxa ◽  
2022 ◽  
Vol 530 (2) ◽  
pp. 189-197
Author(s):  
JULIENE DE FÁTIMA MACIEL-SILVA ◽  
ANA PAULA DO NASCIMENTO PRATA ◽  
MARIA GABRIELA LÓPEZ ◽  
ANDRÉ DOS SANTOS BRAGANÇA GIL
Keyword(s):  
New Species ◽  
Native Species ◽  
The State ◽  
Mature Fruit ◽  
Annual Habit ◽  
Northern Brazil ◽  
Seasonally Flooded ◽  
A New Species

A new species of Bulbostylis (Cyperaceae), only known from the Brazilian Amazonian coast, is here described and illustrated. Bulbostylis litoreamazonicola was found growing over dunes, in seasonally flooded restinga vegetation, and in humid fields near the mangroves from the State of Pará, Northern Brazil. This is the fifth Brazilian-native species of Bulbostylis lacking a persistent stylopodium on the mature fruit. The new species is mainly characterized by its annual habit, simple anthelate inflorescences, densely hispid to hispidulous longitudinally ribbed scapes, pubescent glumes, and cordiform nutlets.

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