13 research outputs found
Consequences of flow turbulence : Biomass partitioning and Plastic responses in morphology
Water movement has a major influence on plant growth in aquatic ecosystems. Although the
plants growing in shallow lakes and wetlands are not experiencing mean flow, they also experience water
movement as flow turbulence. The objective of the current study was to observe the variations of
morphology and biomass partitioning in Egeria densa and Chara fibrosa when exposed to three different
turbulence levels. Chara fibrosa has been observed to have shorter internodal lengths, less number of
internodes when exposed to increased turbulence, while reducing the lateral branching. Egeria densa has
been observed to reduce biomass gain and lateral branching while increasing the shoot:root ratio.
Morphological variations of C. fibrosa and E. densa are more or less similar while their responses to flow
turbulence directed towards their survival in respective condition
Study on the efficiency of removing some environmental pollutants in yellow water by using sand and brick powder
Urine and flush water is known as yellow water in general. Releasing of untreated urine to the
environment causes bad odor, aquatic and terrestrial pollution also. The main focus of this research is to
investigate the usage of sand and red brick powder to remove environmental pollutants in yellow water.
Filtration column used for the study was packed by using sand or brick particles in the range of 0.270-
0.355 mm diameter. Continuous flow filtration through column of sand or brick powder was investigated
for removal of total nitrogen, color, conductivity and COD caused by urine. Whilst brick powder
demonstrates good filtration efficiency, sand is found to be inefficient for the intention. Initial efficiencies
demonstrated by brick powder for removal of total nitrogen, color, conductivity and COD were 93%, 92%,
55%, 65% respectively and decreased upon continuous filtration except for total nitrogen. During the
study, total nitrogen removal efficiency remained constant
Preliminary study on the influence of water level on the growth and morphology of
Limnocharis flava, a species native to tropical America, is naturalized as a noxious weed in Sri Lanka, India and some other Southeast Asian countries. It is widespread in flood plains, wetlands and agricultural wetlands resulting in poor drainage. In the current study, the influence of different water conditions on growth, development and morphology of L. flava was investigated. Plants were grown on experimental pots filled with wetland soil, simulating flood, standing water and dry conditions. The highest biomass and relative growth rate was observed in the plants grown at flood conditions, while the lowest total biomass content was observed in the plants grown at dry conditions. L. flava showed morphological adaptations in different water conditions, including significant differences in the relative biomass allocation for root, petioles and leaves. Root biomass significantly increased in flooded conditions. Observed decrease in leaf area and increase in leaf total chlorophyll content may facilitate the survival in dry conditions. Plant mortality and no production of inflorescence may indicate the difficulty in surviving at dry conditions. No significant difference was observed between the plants grown under ‘high flood’ conditions and ‘low flood’ conditions. Overall, L. flava showed difficulties to grow under dry conditions, but performed well under other conditions