scholarly journals Effects of Water Level Fluctuation on Waterbirds Distribution and Aquatic Vegetation Composition at Natural Wetland Reserve, Peninsular Malaysia

ISRN Ecology ◽  
2011 ◽  
Vol 2011 ◽  
pp. 1-13 ◽  
Author(s):  
Muhammad Nawaz Rajpar ◽  
Mohamed Zakaria

The effects of water level fluctuations on waterbirds distribution and aquatic vegetation composition was determined using distance sampling point count method and direct visual observation at Paya Indah Natural Wetland Reserve, Peninsular Malaysia. A total of 2563 waterbird individual of 28 species and 8 families were detected in three habitats, that is, marsh swamp (68.59%), open water body (18.42%), and lotus swamp (12.99%). Porphyrio porphyrio was the most dominant species in marsh swamp (45.39%), and lotus swamp (23.42%), whereas Dendrocygna javanica (42.16%) was the most abundant in open water body. The highest water level for marsh swamp (2.313 m) and lotus swamp (2.249 m) was recorded in January, 2008 and for open water body (2.572 m) in January and April, 2008. In contrast, the lowest water level for marsh swamp (2.048 m) and lotus swamp (1.834 m) was determined in October, 2008 and for open water body (2.398 m) in January, 2009. Pearson test indicates weak linear correlationship between water level and waterbird abundance in lotus swamp habitat (r2=0.120,P>0.05) and in marsh swamp (r2=0.100,P>0.05) and negative linear correlationship (r2=−0.710,P>0.05) in open water body habitat. Canonical correspondence analysis indicated strong correlationship between waterbird abundance and vegetation (73.0%) in open water body, and weaker association (29.8%) in lotus swamp. The results of this study indicate that water level is a major factor that influences the relative abundance and distribution of ducks, swamphen, crakes, herons, jacanas, and moorhens directly and indirectly. In addition, it also effects on the dynamics of aquatic vegetation composition such as, emergent, submerged, and grasses in this wetland reserve.

2011 ◽  
Vol 2011 ◽  
pp. 1-17 ◽  
Author(s):  
Muhammad Nawaz Rajpar ◽  
Mohamed Zakaria

Birds are the most conspicuous and significant component of freshwater wetland ecosystem. Presence or absence of birds may indicate the ecological conditions of the wetland area. The objectives of this study were to determine bird species abundance and their relationship with microclimate and habitat variables. Distance sampling point count method was applied for determining species abundance and multiple regressions was used for finding relationship between bird species abundance, microclimate and habitat variables. Bird species were monitored during November, 2007 to January, 2009. A total of 8728 individual birds comprising 89 species and 38 families were detected. Marsh Swamp was swarmed by 84 species (69.8%) followed open water body by 55 species (17.7%) and lotus swamp by 57 species (12.6%). Purple swamphenPorphyrio porphyrio(9.1% of all detections) was the most abundant bird species of marsh swamp, lesser whistling duck—Dendrocygna javanica(2.3%) was dominant species of open water body and pink-necked green pigeon—Treron vernans(1.7%) was most common species of lotus swamp. Results revealed that the habitat characteristics such as vegetation composition (i.e. emergent and submerged vegetations, grasses, shrubs, and trees), vegetation structures (tree diameter and height) and microclimate variables (temperature, relative humidity and light intensity) were the key factors that influenced the distribution, diversity and density of the wetland bird species. This study also revealed that the wetland bird species have adapted a fairly unique set of microhabitat and microclimate conditions.


Water ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 2651
Author(s):  
Qiang Liu ◽  
Liqiao Liang ◽  
Xiaomin Yuan ◽  
Sirui Yan ◽  
Miao Li ◽  
...  

Water level fluctuations play a critical role in regulating vegetation distribution, composition, cover and richness, which ultimately affect evapotranspiration. In this study, we first explore water level fluctuations and associated impacts on vegetation, after which we assess evapotranspiration (ET) under different water levels. The normalized difference vegetation index (NDVI) was used to estimate the fractional vegetation cover (Fv), while topography- and vegetation-based surface-energy partitioning algorithms (TVET model) and potential evaporation (Ev) were used to calculate ET and water evaporation (Ep). Results show that: (1) water levels were dramatically affected by the combined effect of ecological water transfer and climate change and exhibited significant decreasing trends with a slope of −0.011 m a−2; and (2) as predicted, there was a correlation between water level fluctuation at an annual scale with Phragmites australis (P. australis) cover and open-water area. Water levels also had a controlling effect on Fv values, an increase in annual water levels first increasing and then decreasing Fv. However, a negative correlation was found between Fv values and water levels during initial plant growth stages. (iii) ET, which varied under different water levels at an annual scale, showed different partition into transpiration from P. australis and evaporation from open-water area and soil with alterations between vegetation and open water. All findings indicated that water level fluctuations controlled biological and ecological processes, and their structural and functional characteristics. This study consequently recommends that specifically-focused ecological water regulations (e.g., duration, timing, frequency) should be enacted to maintain the integrity of wetland ecosystems for wetland restoration.


1984 ◽  
Vol 62 (2) ◽  
pp. 310-316 ◽  
Author(s):  
V. J. Lieffers

Emergent vegetation was sampled in 15 oxbow lakes in a 50-km segment of the Athabasca River in northeastern Alberta. Cover of individual species was visually assessed in plots at the outer, middle, and (or) inner edge of the emergent zone of each lake (n, 37 sample units). Detrended correspondence analysis showed two main axes of variation. The first axis related to salinity. Water conductivity ranged from 170 to 12200 μS cm−1 and community types ranged from freshwater fens to saline wetland communities dominated by Scolochloa festucacea, Scirpus maritimus, and Triglochin maritima. The second axis of variation related to water-level fluctuations. Half of the lakes had an increase in water level in the recent past (ca. 6–30 years). In these lakes, Typha latifolia was dominant in both grounded and floating substrates subjected to increased water levels. Sedge communities dominated by Carex rostrata, C. aquatilis, and Acorus calamus were common in sites with stable water levels. In freshwater lakes, floating substrates were established over open water by the lateral growth of floating stems of Calla palustris and Potentilla palustris. Floating substrates were not in the saline sites probably because these open-water colonizers were not present under saline regimes.


1988 ◽  
Vol 25 (8) ◽  
pp. 1175-1183 ◽  
Author(s):  
J. E. Flint ◽  
R. W. Dalrymple ◽  
J. J. Flint

The sequence of units (from the base up) in the Sixteen Mile Creek lagoon (Lake Ontario) mimics the longitudinal sequence of surficial environments: pink silt—overbank (flood plain – dry marsh); bottom sand—stream channel and beach; orange silt—marsh; gyttja—wet marsh and very shallow (deltaic) lagoon; and brown and grey clay—open-water lagoon. This entire sequence accumulated over the last 4200 years under slowly deepening, transgressive conditions caused by the isostatic rise of the lake outlet. Land clearing by European settlers dramatically increased the supply of clastic sediment and terminated the deposition of the organic-rich silty clays (gyttja) that make up most of the lagoon fill.Because the gyttja and beach sand are interpreted to have accumulated in water depths of less than 0.5 m, the elevation–time plot of 14C dates from these units can be used to reconstruct a very closely constrained lake-level curve. The data indicate that water levels have risen at an average rate of 0.25 cm/a over the last 3300 years as a result of differential, isostatic rebound. Superimposed on this trend are water-level oscillations with amplitudes on the order of 1 m and periods of several hundred years. These oscillations are synchronous and in phase with water-level fluctuations in Lake Michigan, and with a variety of other climatic variations in North America and Europe. We propose, therefore, that the water-level oscillations are a result of long-term, climatically produced variations in precipitation in the Great Lakes drainage basin.


2008 ◽  
Vol 13 (1) ◽  
pp. 133-144
Author(s):  
Andrzej T. Jankowski ◽  
Marek Ruman

Abstract The aim of the paper is to assess the fluctuations of water levels in the Turawa Reservoir (50° 43’ N, 18° 08’ E) in relation to the tourist use of the water body. The reservoir is situated within the macroregion of the Silesian Lowland in the mesoregion of the Opole Plain. In administrative terms, the reservoir is situated in the pole Province within the borough of Turawa. In hydrological terms, in turn, it is situated in the catchment area of the Mała Panew river, which belongs to the basin of the Odra river. The Turawa Reservoir was opened for use in 1938, and in 1948 it was filled with water to its maximum for the first time. At present, the surface area of the reservoir, when it is filled with water to its maximum, is about 20.8 km2, its volume 99.5 mln m3, and its depth exceeds 13 meters. In the period of hydrological years 1976-2000 water levels in this reservoir were characterized by high, unnoticed in natural conditions, amplitudes of changes reaching 6.99 m. Anthropogenically stimulated fluctuations in the water level result in conflicts in terms of tasks and functions that the Turawa Reservoir was designed for. Changes in the level of the water surface in the Turawa Reservoir resulted from the impact of the natural factors (thaw and rainfall related high water levels), as well as anthropogenic ones (the need to improve sailing conditions, water supply for industrial and municipal needs). Decreasing the fluctuations of water levels in the Turawa Reservoir is necessary in order to maintain its tourist-recreational functions and keep the ecological condition of its waters at the appropriate level.


Author(s):  
Marina Vilenica ◽  
Ivana Pozojević ◽  
Natalija Vučković ◽  
Zlatko Mihaljević

Many studies have reported a negative impact of freshwater habitat modification on biota. Nevertheless, some man-made water bodies have proven to be valuable for biodiversity conservation as they can harbour many species. We investigated 36 man-made water bodies to determine their suitability as habitats for Odonata. Larvae were sampled in littoral, during the summer months of 2016 and 2017. At each sampling site, ten samples were collected using a benthos hand net. A total of 21 Odonata species was recorded. Odonata assemblages mainly consisted of common widespread species. Yet, at Vlačine Reservoir, located in the Dinaric Western Balkan ecoregion, we also recorded a rare and endangered Mediterranean species, Lindenia tetraphylla (Vander Linden, 1825). Aquatic and riparian vegetation, water level fluctuations and dissolved oxygen concentration had the highest influence on Odonata, showing that man-made water bodies with a well-developed riparian zone and aquatic vegetation, and with low daily and seasonal water level fluctuations, can provide suitable habitats for diverse Odonata species. Odonata are among the sensitive freshwater insects widely used as ecological indicators and umbrella species, therefore these results about their assemblages in heavily modified and man-made habitats could contribute to future conservation activities of freshwater biota and habitats.


1997 ◽  
Vol 47 (1) ◽  
pp. 90-104 ◽  
Author(s):  
Sheila R. Vardy ◽  
Barry G. Warner ◽  
Ramon Aravena

AbstractSix cores were collected from a small peatland on the Tuktoyaktuk Peninsula, yielding up to 1.8 m of organic material and 1.2 m of ice-rich material. Stratigraphic relationships, radiocarbon dating, and pollen, plant macrofossil, and isotopic analyses are used to reconstruct the developmental history of the peatland. Organic matter began to accumulate in the basin about 7200 yr B.P., during a period when the climate is thought to have been warmer than present. Initially the permafrost table was probably below the bottom of the basin, and an open-water mineral wetland with emergent and submergent aquatic vegetation occupied the site. Enriched δ18O values from ice samples confirm the existence of an open water body with a water balance strongly affected by evaporation. Transformation to a graminoid fen peatland was underway by 6300 yr B.P. Permafrost and ice began to form in the peatland at this time. Low-centered polygons probably began to develop by 4700 yr B.P. and subsequently evolved into the high-centered polygons which characterise the southwestern part of the peatland today. Peat accumulation in the polygons has been extremely slow for the last 4000 years. The eastern, wetter part of the basin has largely remained unchanged since its inception about 7000 yr B.P. Development of the peatland may be linked to permafrost formation that was controlled by regional climate changes during the Holocene.


Geografie ◽  
2004 ◽  
Vol 109 (2) ◽  
pp. 129-144
Author(s):  
Arvo Järvet

Lake Vörtsjärv as a very shallow (mean depth 2.8 m) water-body and considerable water level fluctuations cause changes in both the surface area and volume of the lake. Due to the shallowness of the lake, low level periods are accompanied by several phenomena detrimental to its ecosystem, like cyanophyte blooms, overgrowing with macrophytes, resuspension of phosphorous compounds, restricted spawning places for pike and winter fish kills. In the years of low water level the perspectives to catch in established fishing sites using particular gear as well as access to harbours are hindered. Causal relations between the water regime and ecological state of the lake Vörtsjärv have been discussed in this paper.


Sign in / Sign up

Export Citation Format

Share Document