A silver-lining in Alternanthera philoxeroides invasion: exploring sustainable alternative use in the tropics.
Tropical freshwater ecosystems;an indispensible means of sustenance, food and livelihood for millions of poor people of the developing world; are prone to massive biodiversity declines due to huge pressures of over-exploitation and invasive species. Without mitigation of the problem of biological invasion of the tropics, half the world's population will be soon facing serious food shortages. In an attempt to bridge the gap between successful management of an invasive plant, and a sustainable source of supplementary food for the marginalized population, this pilot study investigated the potential utilization of the widely prevalent invasive Alternanthera philoxeroides (Alligatorweed) as a leafy vegetable. Questionnaire-based field-surveys revealed a much higher section of rural populace utilized Alligatorweed as food/fodder as compared to the urban/semi-urban populace. ED-XRF analysis of young 'edible' shoots of Alligatorweed revealed it to have good concentration of essential elements like potassium, calcium, iron, zinc and manganese. However, significant positive correlations of manganese (p<0.01) between Alligatorweed and its soil-substratum indicated its metal hyper-accumulative potential. Hence, Alligatorweed should be used for human-consumption only when it is harvested from non-polluted eco-regions. This study explores a positive utility of the invasive Alligatorweed and in turn indicates its possible managerial approach. In a country where a large populace is mal-nourished, consumption of Alligatorweed as supplementary-vegetable can not only help in controlling its invasion into our pristine aquatic/wetland ecosystems, but also help in generation of cheap and sustainable source of supplementary food for the marginalized section of our country.