Vegetation and nutrient status of northern Michigan fens

The vegetation, selected characteristics of shallow groundwater, and depth to water were examined in five fens in northern Lower Michigan. The field layer was the dominant stratum in all five fens and contained a total of 85 vascular species with a mean density of 30 vascular species per stand. Carex lasiocarpa was the most prevalent dominant plant and attained a frequency–presence index (FPI) of 8000 of a possible 10 000 and a mean importance value of 33 of a possible 200. Other common dominants in decreasing order of FPI were Carex aquatilis (6640), Myrica gale (4636), and Andromeda glaucophylla (2000). Common subordinates were Hypericum virginicum (2639), Muhlenbergia glomerata (2466), and Campanula aparinoides (1400). The vegetation was relatively homogeneous as indicated by a homogeneity index of 58%.The shallow groundwaters were minerotrophic with pH values ranging from 5.7 to 7.0 and calcium concentrations of 11.0 to 75.0 mg/ℓ. Four of the fens were on floating mats and had relatively stable water levels while the fifth was on a grounded mat and was subject to substantial water level fluctuation.Three previously described alkaline lake-edge kettle-hole 'bog' communities were found to be similar to the fens in species composition and water chemistry.

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Vegetation, hydrology, and development of a coastal mire in Hokkaido, Japan, affected by flooding and tephra deposition

Canadian Journal of Botany ◽

10.1139/b01-011 ◽

2001 ◽

Vol 79 (3) ◽

pp. 341-361 ◽

Cited By ~ 12

Author(s):

Stefan Hotes ◽

Peter Poschlod ◽

Hiroshige Sakai ◽

Takashi Inoue

Keyword(s):

Sea Water ◽

Ionic Composition ◽

Plant Macrofossils ◽

Vegetation Pattern ◽

Water Levels ◽

Myrica Gale ◽

Mineral Deposition ◽

Volcanic Ejecta ◽

Induced Changes ◽

Flooding Events

Mires in coastal lowlands in Hokkaido, northern Japan, have repeatedly been affected by flooding events and tephra (aerially transported volcanic ejecta) deposition during their development. Vegetation, hydrology, and stratigraphy of Kiritappu Mire in eastern Hokkaido were investigated along two transects and are discussed in relation to disturbance by mineral deposition. The vegetation pattern showed little relation to past geologic events. Five plant communities, two of which (A and C) could be further divided into subgroups, were distinguished (A, Alnus japonica - Spiraea salicifolia community; B, Sasa chartacea community; C, Myrica gale var. tomentosa - Sphagnum fuscum community; D, Carex lyngbyei community; E, Carex subspathacea - Aster tripolium community). Water levels, pH, electric conductivity, and ionic composition of groundwater and surface water were measured in communities A-C. Mean water levels were similar in communities A and C; in community B, it was lower. The pH was higher in community A than in communities B and C. Ion concentrations were influenced by sea water at some sites. Plant macrofossils and ash contents of 31 cores were analysed. Sedge roots were the dominant peat component, often mixed with remains of Phragmites australis, Sphagnum spp., and Polytrichum juniperinum var. strictum. Ash contents were high, and up to nine different mineral layers consisting of tephra, sand, silt, and clay were detected. In some cases, mineral deposition induced changes in the macrofossil composition of the peat. However, in a greater number of cases, no changes in the macrofossil composition were found at the mineral layers, and most shifts were not related to mineral deposition.Key words: mire, vegetation, hydrology, disturbance, flooding, tephra.

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The Effects of Water Levels and Interspecific Competition on Two Carex Species in a Temperate Wetland of Northeast China

Sustainability ◽

10.3390/su122410654 ◽

2020 ◽

Vol 12 (24) ◽

pp. 10654

Author(s):

Wenwen Tan ◽

Li Sun ◽

Xinhou Zhang ◽

Changchun Song

Keyword(s):

Spatial Distribution ◽

Water Level ◽

Interspecific Competition ◽

Distribution Patterns ◽

Wetland Plants ◽

Water Levels ◽

Carex Lasiocarpa ◽

Temperate Wetland ◽

The Relationship ◽

Spatial Distribution Characteristic

Zonation along a water level is the main spatial distribution characteristic of wetland plants. This is mainly because of the influences of hydrological conditions and interspecific competition, which finally narrow the fundamental niche of a species to its realized niche. In the present study, a controlled experiment was conducted in order to analyze the relationship between Carex lasiocarpa/Carex pseudocuraica and Glyceria spiculosa, in conditions of three competitive treatments at four water levels. The results showed that in no competition, C. lasiocarpa preferred low water levels, but this preference receded when competing with G. spiculosa. In contrast, C. pseudocuraica had greater preference for low water level when competing with G. spiculosa. The root/shoot ratios of the two Carex species decreased with increasing water levels, but they were almost unaffected by different competition treatments. With the increase in water level during full competition with G. spiculosa, the competitive ability of C. lasiocarpa showed an increasing trend, whereas a contrary trend was observed in C. pseudocuraica. Our results suggested the effects of water levels and their interactions with interspecific competition varied between the two Carex species and played an important role in determining spatial distribution patterns and potential community succession of wetland plants.

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Structural and functional responses of Carex aquatilis to increasing sodium concentrations

Wetlands Ecology and Management ◽

10.1007/s11273-020-09746-9 ◽

2020 ◽

Vol 28 (5) ◽

pp. 753-763

Author(s):

Dale H. Vitt ◽

Lilyan C. Glaeser ◽

Melissa House ◽

Samantha P. Kitchen

Keyword(s):

Oil Sands ◽

Belowground Biomass ◽

Water Levels ◽

Strongly Correlated ◽

Functional Responses ◽

Carex Aquatilis ◽

Athabasca Oil Sands Region ◽

Threshold Response ◽

Brackish Marshes ◽

High Concentrations

Abstract Carex aquatilis is a widespread boreal species that is abundant in open fens and marshes. The species has broad natural tolerances to differing water levels and ion concentrations including occurrences in brackish marshes but not sodic wetlands. Sandhill Wetland, constructed on Syncrude Canada Ltd. mineral surface lease in the Athabasca Oil Sands Region, is a research site that was engineered to support a self-sustaining wetland. The site is currently in its eighth year post wet-up and is partially dominated by C. aquatilis. Increasing Na+ concentrations in the porewaters at Sandhill Wetland are an on-going concern for the performance of the existing plant communities. Here we examine the responses of C. aquatilis to an increasing regime of sodium carried out in a greenhouse experiment. We posed three questions for this experiment: (1) is there a threshold response for performance of C. aquatilis to increasing sodium, (2) if so, does it occur in the range of sodium that is present at current reclamation programs, and (3) is C. aquatilis resistant to high concentrations of sodium? Carex aquatilis survived all treatment concentrations of sodium including the highest treatment of 2354 mg L− 1. In general, both structural and functional attributes of C. aquatilis did not differ between the 17 and 1079 mg L− 1 treatments; however, performances of all attributes were reduced in the 2354 mg L− 1 treatment. Belowground biomass had greater decreases compared to aboveground components, including both biomass and photosynthesis. The aboveground decreases in performance were associated with exclusion of sodium from the aboveground components by the belowground components. Reduction in photosynthesis was strongly correlated with reduced stomatal conductance and lower transpiration. Although C. aquatilis demonstrated a wide tolerance to sodium concentrations, a clear threshold was present between 1079 and 2354 mg L− 1. These decreases in performance in our greenhouse trials were at levels currently present at Sandhill Wetland, and careful assessment of sodium concentrations in the near future needs to be continued.

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INFLUENCE OF SOIL pH AND HUMIDITY ON SURVIVAL OF CEPHALOSPORIUM GRAMINEUM IN INFESTED WHEAT STRAW

Canadian Journal of Plant Science ◽

10.4141/cjps68-045 ◽

1968 ◽

Vol 48 (3) ◽

pp. 245-252 ◽

Cited By ~ 9

Author(s):

G. W. Bruehl ◽

P. Lai

Keyword(s):

Soil Ph ◽

Higher Plants ◽

Water Levels ◽

Alkaline Soil ◽

Surface Layers ◽

Trichoderma Spp ◽

Ph Values ◽

Ph Range ◽

Cephalosporium Gramineum ◽

Wilting Point

Cephalosporium gramineum survived in and sporulated most profusely on wheat straws in soil at pH 3.9 to 5.5. Strongly acid (pH 3.3) and alkaline soil (pH 7.6 or greater) reduced survival. The sporodochial stage (Hymenula cerealis) formed at pH values between 3.9 and 8.4, but most abundantly at pH 4.8 to 5.1. While acidity favored both saprophytic survival and sporulation, the pH’s of most wheat lands of Washington are within the pH range favorable for the pathogen.Saprophytic colonization of straw by Trichoderma spp. was favored by acidity (greatest at pH 3.3 to 3.9), and colonization by saprophytic Fusarium spp. by alkalinity (greatest at pH 8.2 to 8.8).Air-dried soil was brought to various relative humidities (RH) over glycerine and water solutions. Cephalosporium gramineum survived best in straw in contact with soil at the lowest RH tested (ca. 82%) and least well at an RH near 90%. Survival was reduced in soils with relative humidities between 90 and 86%, water levels below those of soil at the permanent wilting point for higher plants. Such humidities exist in surface layers of summerfallow and crop lands during portions of the summer in Washington.Penicillium brevi-compactum and P. steckii were the main colonists of the straws at RH values of 95% or lower.

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Effects of competition from shrubs on herbaceous wetland plants: a 4-year field experiment

Canadian Journal of Botany ◽

10.1139/b89-094 ◽

1989 ◽

Vol 67 (3) ◽

pp. 708-716 ◽

Cited By ~ 60

Author(s):

Paul A. Keddy

Keyword(s):

Plant Cover ◽

High Water ◽

Water Levels ◽

Low Fertility ◽

Individual Species ◽

Wetland Plant ◽

Evergreen Species ◽

Myrica Gale ◽

Competitive Release ◽

The Individual

While competition is known to occur among some species in some plant communities, we are not yet able to predict in which environments, or among which species, competitive interactions will be most intense. The objective of this study was to test for competition in a wetland plant community and then to determine which environments and which species were influenced by competition. The study site was the transition zone between shrubs and herbaceous plants on a lakeshore. To test for competitive release, shrubs were removed from treatment plots paired with controls in 25 sections of shoreline and cover of herbaceous species was monitored for 4 years. There were highly significant increases in cover, richness, and diversity in the removal plots, but less than one quarter of the individual species responded significantly. In general, these were small, partly evergreen species with high densities of buried seeds (e.g., Drosera intermedia, Hypericum boréale). On shores with frequent disturbance and low fertility there was no evidence for competitive release. The reduction in plant cover during a summer with high water levels suggests that lakeshores shift from abiotic to biotic structuring according to the water level in a particular year or series of years. Superimposed upon this is variation attributable to the type of shoreline and the type of species. Key words: competition, disturbance, exposure, lakeshores, Myrica gale, shrubs, wetlands, zonation.

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Status of agricultural technology innovation in swampy land

E3S Web of Conferences ◽

10.1051/e3sconf/202130603023 ◽

2021 ◽

Vol 306 ◽

pp. 03023

Author(s):

Agus Hasbianto ◽

Sri Hartati ◽

Eni Siti Rohaeni ◽

Muhammad Yasin

Keyword(s):

Technology Innovation ◽

Group Discussion ◽

Nutrient Status ◽

High Water ◽

Water Levels ◽

Agricultural Technology ◽

Survey Method ◽

Technology Innovations ◽

The Status ◽

Mechanical Devices

This research was carried out to know the status of agricultural technology innovation used by farmers in lowland swamps and formulate policy recommendations for relevant stakeholders in land management for sustainable farming. The study was conducted using a survey method with a structured questionnaire and focus group discussion in 5 villages in Banjar Regency, South Kalimantan, with a total of 48 respondents. The results showed that the main commodity cultivated by farmers in lowlands was rice, where the agricultural technology innovation used was still limited to the use of superior varieties, while the use of other technologies was still low which resulted in low farm productivity. The causes of limited use of agricultural technology innovations include poorly organized land conditions and high-water levels in the land that make it difficult for equipment operations, narrow land area per farmer, limited infrastructure for mobility of agricultural machinery, limited capital, and low educational level of the main actors. Some of the proposed recommendations are improving cultivation technology, especially fertilization according to nutrient status and yield targets, land and water management, using mechanical devices as needed, and increasing the role of related institutions.

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Hydrological Characteristics of the Te Hapua Wetland Complex:The Potential Influence of Groundwater Level, Bore Abstraction and Climate Change on Wetland Surface Water Levels

10.26686/wgtn.16973461.v1 ◽

2021 ◽

Author(s):

◽

Craig Wayne Allen

Keyword(s):

Climate Change ◽

Surface Water ◽

Groundwater Level ◽

Hydrological Cycle ◽

Shallow Groundwater ◽

Water Levels ◽

Groundwater Abstraction ◽

Potential Threat ◽

Through Flow ◽

Future Viability

<p>Te Hapua is a complex of small, privately owned wetlands approximately 60 km northwest of Wellington. The wetlands represent a large portion of the region's remaining palustrine swamps, which have been reduced to just 1% of the pre-1900 expanse. Whilst many land owners have opted to protect wetlands on their land with covenants, questions have been raised regarding potential threats stemming from the wider region. Firstly, some regional groundwater level records have shown significant decline in the 10 to 25 years they have been monitored. The reason for this is unclear. Wetlands are commonly associated with groundwater discharge, so a decline in groundwater level could adversely affect wetland water input. Secondly, estimated groundwater resources are currently just 8% allocated, so there is potential for a 92% increase in groundwater abstraction from aquifers that underlie the wetlands. Finally, predictions of future climate change indicate changes in rainfall quantity and intensity. This would likely alter the hydrological cycle, impacting on rainfall dependant ecosystems such as wetlands as well as groundwater recharge. Whilst previous ecological surveys at Te Hapua provide valuable information on biodiversity and ecological threat, there has been no detailed study of the hydrology of the wetlands. An understanding of the relationship between the surface water of the wetlands and the aquifers that underlie the area is important when considering the future viability of the wetlands. This study aims to define the local hydrology and assess the potential threat of 'long term' groundwater level decline, increased groundwater abstraction and predicted climate change. Eleven months of water level data was supplied by Wellington Regional Council for three newly constructed Te Hapua wetland surface water and adjacent shallow groundwater monitoring sites. The data were analysed in terms of their relative water levels and response to rainfall. A basic water balance was calculated using the data from the monitoring sites and a GIS analysis of elevation data mapped the wetlands and their watersheds. A survey of 21 individual wetlands was carried out to gather water quality and water regime data to enable an assessment of wetland class. Historical groundwater level trends and geological records were analysed in the context of potential threat to the wetlands posed by a decline in groundwater level. Climate change predictions for the Kapiti Coast were reviewed and discussed in the context of possible changes to the hydrological cycle and to wetlands. Results from the wetland survey indicated that there are two distinct bands of wetlands at Te Hapua. Fens are found mostly in the eastern band and are more likely to be discharge wetlands, some of which are ephemeral. Swamps are found mostly in the western band and are more likely to be recharge wetlands. Dominant water input to fens is via local rainfall and local through-flow of shallow groundwater, especially from surrounding dunes. The eastern band of wetlands is typified by higher dunes and hence has greater input from shallow groundwater than wetlands in the western band. Dominant water input to swamps is via local rainfall, runoff, and through-flow from the immediate watershed and adjacent wetlands. Overall, the future viability of the Te Hapua wetland complex appears promising. Historical groundwater declines appear to be minimal and show signs of reversing. Abstraction from deep aquifers is not likely to impact on wetland water levels. Climate change is likely to have an impact on the hydrological cycle and may increase pressure on some areas, especially ephemeral wetlands. The effect of climate change on groundwater level is more difficult to forecast, but may lower water level in the long term.</p>

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