Presence of tropical hydrophytes in relation to limnological parameters - a study of two freshwater ponds in Kolkata, India

Abstract

The presence of different species of hydrophytes was investigated in relation to Secchi disk visibility, pH, dissolved oxygen, electrical conductivity, total Kjeldahl nitrogen, total phosphorus and chlorophyll-a concentration in two tropical ponds nearby Kolkata, India, during a three years period (June 1999 to May 2002. The dominant flora in the ponds namely, Alternanthera philoxeroides, Nymphoides hydrophylla, Lemna aequinoctialis, and Vallisneria spiralis were found to subsist over a wide amplitude of nutrient levels thereby showing their adaptability to highly eutrophic ecosystems, a common feature of the tropics. However, the presence of some minor species could be associated with a narrow range of specific limnological variables.

Distribution and habitat characteristics of Vallisneria spiralis L. in Croatia

“…The aquatic vegetation of the spring was surveyed several times, from 2014 to 2016 (Rimac et al 2018) and in 2018 (Vuković et al 2018(Vuković et al , 2019, however, V. spiralis was never confirmed. In all localities surveyed within this study, measured values of pH and alkalinity indicate slightly basic, alka-20/1 • 2021, 7-18 Anja Rimac, Antun Alegro, Vedran Šegota, Nikola Koletić, Igor Stanković, Sandro Bogdanović & Nina Vuković Distribution and habitat characteristics of Vallisneria spiralis L. in Croatia line conditions and along with measured water temperature and electrical conductivity fall within the ranges previously reported for V. spiralis (Hussner & Lösch 2005, Mukhopadhyay & Dewanji 2005, Rai & Tripathi 2009, Ejsmont-Karabin & Hutorowicz 2011, Collas et al 2012. The species was growing on various substrates, muddy, sandy and gravely, in up to 1.5 m deep water, as already observed in other studies (Hussner & Lösch 2005, Zarubina & Sokolova 2011.…”

“…Vallisneria spiralis is a typical component of lowland meso-to eutrophic aquatic habitats, both lotic and lentic (Hussner & Lösch 2005, Mukhopadhyay & Dewanji 2005, Bolpagni et al 2015, Anđelković et al 2016. It was reported from oligotrophic conditions as well, however, displaying lower growth rates (Bolpagni et al 2015).…”

Morphometric and biotic variables as potential predictors ofLudwigia sedoides(Humb. & Bonpl.) Hara in a large Amazonian reservoir

“…Other variables, not considered here, must explain the remaining variation. For example, the influence of nutrients, sediment grain size, water quality and presence of herbivores should be considered in future research (Mukhopadhyay and Dewanji, 2005;Lacoul and Freedman, 2006), as a means of improving prediction and explanation of the distribution of L. sedoides in reservoirs.…”

The impact of duckweed growth on water quality in sub-tropical ponds

“…However, there are some studies on its habitat limnology from India and Bangladesh also (Pandit et al 1978;Nurul Islam and Khondker 1991;Khondker et al 1994). Apart from the influence of both nitrogen and phosphorus on growth of duckweeds (Rejmánková 1975;De Groot et al 1987;Portielje and Roijackers 1995;Mukhopadhyay and Dewanji 2005), duckweed root lengths have been related to be indicative of changes in water quality as well (Lüönd 1980;Elster et al 1995). The use of duckweeds in waste water treatment has also long attracted global attention due to its great capacity in absorbing nutrients (Vermaat and Hanif 1998;Körner et al 2003;Cheng and Stomp 2009), but even then the plants have to be harvested regularly to maintain a healthy duckweed crop (Skillicorn et al 1993).…”