S. Dam Roy

Changes in phytochemicals, anti-nutrients and antioxidant activity in leafy vegetables by microwave boiling with normal and 5% NaCl solution

The present study investigated the changes in phytochemicals and antioxidant activities in 25 leafy vegetables with two common boiling practices viz., with 5% NaCl solution (BSW) and normal water (BNW) in a domestic microwave oven. Fresh samples (100g) were rich in polyphenols (58.8-296.9mg), tannin (402.0-519.4mg), flavonoids (148.9-614.4mg), carotenoids (69.0-786.3mg), anthocyanin (11.7-493.7mg) and ascorbic acid (245.0-314.2mg). Microwave boiling significantly (p<0.05) decreased/increased phytochemicals but none of the compounds followed same trend in all vegetables. Boiling process reduced anti-nutrients from fresh samples (FS) as observed for nitrate (4.5-73.6% by BSW and 22.5-98.8% by BNW); phytate (6.2-69.7% by BSW and 10.6-57.3% by BNW) and oxalate (14.7-88.9% by BSW and 14.5-87.3% by BNW) but saponin increased in 18 vegetables by BNW while 8 vegetables by BSW. The study revealed differential pattern of change in phytochemical matrix and anti-nutrients in vegetables by microwave boiling which will help in devising efficient cooking practices and contribute in health and nutritional security.

Enhancing nutrient recovery and compost maturity of coconut husk by vermicomposting technology

Vermicompost was prepared by five different treatments from relatively resistant coconut husk mixed with either pig slurry or poultry manure. The recovery of vermicompost varied from 35% to 43% and it resulted in significant increase in pH, microbial biomass carbon, macro and micro nutrients concentration. Among the treatments highest relative N (1.6) and K (1.3) recovery were observed for 20% feedstock substitution by pig slurry while poultry manure substitution recorded highest P recovery (2.4). Compost maturity parameters significantly differed and well correlated. The characteristics of different treatments established the maturity indices as C/N 15-20; Cw<1.8; Cw/Norg<0.55; Lignin<10-12; CHA/CFA>1.5 and HI>15.0. The manurial value of the coconut husk compost was improved by feedstock substitution with pig slurry (80:20). The results revealed the technical feasibility of converting coconut husk into valuable compost by feedstock substitution with pig slurry.

Species diversity and distribution of mangroves in Andaman and Nicobar Islands, India

Abstract Despite extensive studies on mangrove ecosystems of Andaman and Nicobar Islands since the 1870s, knowledge of exact species composition is far from complete, and there is a lack of comprehensive locality data. The present study was designed to review the existing literature and to provide an updated checklist of the true mangrove species of the Islands. Preliminary surveys were carried out in seven regions (four from the Andaman group and three from the Nicobar group), and the specific survey sites for detailed study (n=51) were selected based on representativeness, importance, and accessibility. During 2009–2013, all the selected sites were visited, and mangrove species occurrence was recorded. At present, 25 true mangrove species distributed among 10 families and 14 genera were identified vis-à-vis 17 to 36 species reported in earlier studies. The discernible changes in species numbers from earlier studies could mainly be attributed to our exclusion of associated littoral vegetation and of species unlikely to be present among the true mangroves of the Islands. Given their limited geographical area, the low similarity index values between the Andaman and Nicobar Island groups (≤0.4) indicate a need for periodical surveys, as mangrove biodiversity is usually homogenous in regions where there are no impassable dispersal barriers. Further, regular updating of information on the extent and status of mangroves in the Islands is imperative not only to improve our understanding of phytogeography but also for better management and conservation.

Analysis of Perspectives of Self-sufficiency in Vegetable Production Under Tropical Conditions

The government of India is promoting local vegetable production in Andaman and Nicobar Islands in a policy of sustainable development on tropical bay islands. There has been an increase in area and productivity of vegetables and reduced import of vegetables from the mainland. Improved technologies have been transferred to vegetable farms. However, the majority of farmers rely on private agencies for inputs and marketing activities that limit profits. Lack of cold transport, storage facilities, modern collection centers, and processing industry are still challenges to vegetable growers on islands. Use of good agricultural practices for vegetables includes limited use of synthetic chemicals in the island ecosystem. The pace of adoption of improved practices in vegetables needs to be enhanced to ensure off-season availability. Many island cultures employ organic methods by default and a small amount of effort can establish them as organic hubs for vegetable production. Rising tourism and increasing import cost of vegetables increased the necessity of structural changes in production to make islands self-sufficient in vegetable production.

Explaining the status and scope of ecotourism development for livelihood security: Andaman and Nicobar Islands, India

In the past few decades, the tourism sector has emerged as a significant economic activity in island nations, particularly in tropical regions. However, most of the tropical islands face similar constraints, viz., threat to natural resources, chances of biopiracy, impact of climate change, population pressure and unsystematic tourist management. Ecotourism, as a concept, envisages promoting tourism with due regard to natural environment and ecological sanctity of the destination. Archipelago of Andaman and Nicobar (A&N) Islands is one of picturesque geographical creation in the Bay of Bengal, India, in tropical region and is an emerging tourist destination. It was observed that around 2.2 lakhs national and international tourists visit the A&N Islands annually. With tourism sector as an integral component, the service sector with share of 56% in gross state domestic product dominates the island economy. An analysis based on primary survey from various stakeholders associated with the sector revealed that factors such as economy in travel and boarding, availability of tourist facilities and comfort, safety, etc. were major factors that determined the choice of the tourists that visited the islands. The weights given by the tourists to the natural sites in A&N Islands revealed that the landscape topped list with 91.6% score by the visitors followed by beaches (91.3%), scenery (86.5%), reserved forests (84.6%), limestone caves (66.3%) and coral sights (65.8%). Coral sites were given weight of 65.8% of tourists, cultural and historical tourism products 85.4% for the natural history. Similarly, historical sites (83.7%), museums (78.6%) and heritage sites (72.8%) were also among top cites attraction. Recent initiatives by the Andaman administration gives due to care to sustainably develop the tourism infrastructure of the islands to harness the potential of eco-friendly tourism in this picturesque tourist haven.

Wetlands of Small Island Nations in South Asia vis-à-vis the Mainland and Island Groups in India: Status and Conservation Strategies

The wetlands of small island nations in South Asia such as Sri Lanka and the Maldives are compared with that of India with respect to their status, biodiversity, threats and conservation measures. Sri Lanka has diverse coastal habitats, which are known to support fishes (1800 species), marine turtles (5 species), marine mammals (38 species), corals (183 species), mangroves (40 species), birds (100 species), reptiles (33 species) and seagrasses (10 species). The Maldives boasts one of the world’s richest marine biodiversity comprising 250 species of corals, over 1200 of reef fishes, 200 species of sponges, over 1000 species of crustaceans and over 100 species of echinoderms. Marine biodiversity of India comprises 12,913 species, of which more than 5800 species are reported from Andaman and Nicobar Islands. Marine biodiversity of Lakshadweep islands is represented by corals (172 species), fishes (396), sponges (95), molluscs (260), echinoderms (84), crustaceans (80), turtles (04), birds (142), marine mammals (6), seagrasses (07) and mangroves (03). The major threats to these wetlands of South Asian countries are climate change, extreme events like tsunami, coastal erosion, population pressure, habitat destruction and over-exploitation. The chapter emphasises the need for adopting frontier tools for biodiversity documentation and innovative strategies for their conservation.

Innovative Technologies to Sustain Saline Island Agriculture in the Scenario of Climate Change: A Case Study from Andaman Islands, India

In the coastal and humid tropical island region, waterlogging and soil salinity are serious threat to the sustainability of rainfed agriculture due to sea water inundation and intensive monsoon rainfall. In addition, there has been a marked change in surface temperature, rainfall, evaporation, and extreme events linked to climate change affecting the tropical islands. Therefore, an innovative management of waterlogged and saline soils of island ecosystem is imperative for sustainable agricultural production. The current technology enables the transfer of desirable genes from wild relatives to cultivated plants and improvement of land races followed by selection of crops and their varieties by the island farming community for waterlogged and saline conditions. The available evidences suggest that crop planning, multi-stress crop combinations, integrated farming system, and suitable agroforestry models have the potential to provide the basic needs of the people even under stressful and climate change situations. Land shaping measures have great potential to address waterlogging and salinity together while it promotes crop and farming system diversification which are more sustainable than monocropping with rice. In island conditions, rain water harvesting, storage, and its efficient use should be an integral part of the strategy for sustainable agricultural production. In addition, the livelihood of the people can be enhanced by suitable aquacultural practices in the coastal saline soils while sea weed cultivation holds greater promise to diversify the agricultural activities in the island saline environment.

Invasive Species in Freshwater Ecosystems – Threats to Ecosystem Services

Abstract Invasive species refers to non-native species that produce negative consequences in the relatively new habitat or producing effects that human don’t like and deem harmful. In the freshwater ecosystem of tropical islands fishes, amphibians and crustaceans have been introduced for aquaculture, sport, improvement of wild stock, the aquarium trade and biological control. Many have been accidental escapes. Unintended impacts have been alterations to the habitat as well as direct competition for food and living space, introduction of pathogens, hybridisation, environmental and socioeconomic effects. In certain cases, some alien fishes helped to increase the aquaculture production in several countries such as carps. Apart from increased production, the effect of introduction might be irreversible as they will establish and occupy the ecosystem permanently due to their voracious feeding and proliferative breeding habits. The study also calls for strict quarantine measures to check the exotic fish introductions, which might be a beneficial step in conservation of native aquatic fauna under changing climatic conditions in islands.

Indigenous underutilized vegetables for food and nutritional security in an island ecosystem

Indigenous plants are an important component of the traditional food and health systems of rural and tribal communities in tropical regions. However, they do not attract much attention from researchers or in commercial markets. The present study investigated 42 indigenous, under-utilized vegetable plants from the Andaman and Nicobar Islands of India for their food and ecological values. Predominantly, the plants belonged in the Cucurbitaceae, Amaranthaceae, Moraceae and Plantaginaceae families. Fifty seven percent of the vegetables were observed in home gardens and 21.4% were collected from wild habitats. Most of the indigenous vegetables were perennials (71.4%), and included trees, vines and shrubs. Commercial farmers grew mostly exotic vegetables, while many indigenous and under-utilized vegetables were preferred by tribal and local communities. Herbs with good flavour, taste and crispness were preferred in culinary preparations; vegetables with a bitter taste and unique flavour were considered best for health purposes. The indigenous and under-utilized vegetables contained a wide range of nutrients, including Ca, Fe, polyphenols, carotenoids, ascorbic acid and chlorophyll, although they also often contained anti-nutrients including nitrate, phytate, oxalate and saponins. Our findings support the greater use of indigenous underutilized vegetables as promising and locally accepted options to address micronutrient deficiencies among households in geographically challenged regions such as the Andaman and Nicobar Islands. The study also underlined the need to devise strategies for the promotion of these nutrient-rich indigenous foods to improve the nutrition and livelihoods of vulnerable communities.

Investigation and confirmation of white spot syndrome virus (WSSV) infection in wild caught penaeid shrimps of Andaman and Nicobar Islands, India

White spot syndrome virus (WSSV) is one of the most prevalent, widespread and devastating pathogen associated with shrimp population. The present study was aimed at screening the wild caught shrimps from Andaman and Nicobar Islands (ANI) for WSSV infection. Shrimp samples of different penaeid species including Penaeus monodon, Penaeus indicus, Penaeus merguiensis and Metapenaeus monoceros collected from nine different landing centers across the coast of ANI were screened for WSSV infection. Presence of white spots, a typical clinical sign of white spot disease was observed on the exoskeleton of WSSV infected shrimp samples. Out of 241 shrimp samples, 39 samples of P. monodon were found positive for WSSV by nested PCR. Histopathological examination revealed eosinophilic to basophilic intranuclear inclusion bodies in gill tissue which are typical characteristics of WSSV infection. Nucleotide sequence of WSSV isolated from ANI showed 100% identity to the sequences of WSSV reported from Thailand, Taiwan, China, Egypt, Mexico, Korea, France and 99% identity to WSSV reported from India. The detection of WSSV in wild P. monodon of ANI further confirms the virus spread and biogeography.