Ecosystem services of traditional water bodies

People obtain a variety of benefits, both tangible and intangible, from ecosystems. The complex and dynamic interactions between ecosystems and people have resulted in exponential rise of ecosystem services research in recent decade. The economic value of ecosystem services reflects the relative importance of ecosystem services in monetary terms.

The study area is located in red and lateritic zone of West Bengal. Three tanks in this region were selected for the study - Harda Jhil, Alam Sahar, and Rishi Bundh. Among these three tanks, Harda Jhil is located in Binpur Block, Jhargram district, while Alam Sahar, and Rishi Bundh are located in Raipur block, Bankura district.

Tanks were selected after extensive pilot survey during the month of May and June, 2017. The main criteria used while selecting the sample tanks was that they should be multifunctional. Descriptive statistics and Poisson regression model has been used to analyse the data collected from 150 households residing around three selected tanks.

Valuation of ecosystem service

Prevailing local market price of provisioning ecosystem services is used to estimate the economic value of the tank produce that people derive from the selected tanks. Following the Millennium Ecosystem Assessment approach (MEA, 2005) provisioning services are considered for valuation including (shell, fodder, medicinal plant, vegetable, fuel wood, flower, fish, grass, and fruit).

Determinants of the market value of provisioning ecosystem services

Households collect a variety of tank products such as fish, fodder, shell, vegetables, flower etc. either for their own consumption or for the purpose of selling them in local markets for cash income. Using the data of quantity of tank product collected by each household, the researchers estimated the monetary value of tank product in respect of their local market price.

Results and discussion

Economic value of different provisioning services

Overall market value of provisioning ecosystem services of traditional water bodies

The estimated total market value of agricultural production was higher in Harda Jhil than in Alam Sahar and Rishi Bundh. The market value of the product especially from the tanks were lower in Harda Jhil than in Alam Sahar, because of the practice of commercial fishing activities in these tanks. In Rishi Bundh the market value of tank product is higher because of the absence of commercial fishing.

Overall, it is observed that the market value of agricultural production is more compared to other provisioning ecosystem services across the three tanks.

Determinants of household collection of provisioning ecosystem services

In order to identify and analyse factors that influence the household collection of provisioning ecosystem services, Poisson regression model has been employed-

• The monetary value of the household collection of tank products is negatively and significantly associated with the age of the household head, implying that households with younger heads are likely to collect more tank products than their older counterparts.
• The variable women–men ratio is positively and significantly related to the monetary value of the household collection of tank products in combined data and Alam Sahar, meaning that households with more women members are likely to collect a larger share of tank products than their men counterparts.
• The household asset is negatively and significantly related to the collection of tank products in Harda Jhil, Rishi Bundh and for pooled data, which indicates that the wealthier the household lesser the dependence on the tank resources.
• The monetary value of the household collection of provisioning ecosystem services from the tank is positively and significantly associated with household size in Alam Sahar tank and Harda Jhil, which suggests that large size households tend to collect more tank products.
• The variable years of education of the head of the household are negatively and significantly associated with the monetary value of tank products only in Harda Jhil which indicates the lesser dependency on tank products.
• The variable caste (social background) of the household is negatively and significantly influencing the household collection of tank products in Harda Jhil, Alam Sahar and Rishi Bundh, implying that lower caste households are likely to collect more tank products than the higher caste households.
• Distance to the tank is negatively related to the total market value of the household collection of tank products and is significant for pooled data and the Rishi Bundh tank.
• The variable livestock size is positively and significantly associated with the household collection of tank products for the pooled data, Harda Jhil, Alam Sahar and Rishi Bundh models.

The study finds that the average household income from agricultural activities linked with tanks during 2016–2017 was estimated to be INR 1033 (16 USD), INR 7216 (112 USD) and INR 7044 (109 USD) for Alam Sahar, Harda Jhil and Rishi Bundh tanks, respectively.

Conclusions

The valuation of provisioning ecosystem services from tanks comprises of a household collection of tank products, agricultural produce under the command area of tank, livestock and fisheries products.

The study finds that tank resources have economic values and contribute significantly to the household economy of the people living around the selected tanks. Approximately 60 percent of the sampled households depend on the tank resources both for self-consumptions and cash income.

Households living close to tanks pursue a variety of livelihood activities based on resources available in tanks for their sustenance. Households rely heavily on tanks for high-value livelihood activities such as agriculture in the form of irrigation water, silted soil and livestock rearing. Hence, common-pool resources such as tanks form an important source of livelihood for millions of rural people in India.

In addition, other ecosystem services (regulating, supporting) of the tank ecosystem indirectly but significantly contribute to the promotion of local economy which needs to be assessed.

Our result suggests that provisioning services of the tanks tend to secure the livelihood and food security of the poor people living around tanks, which has important policy implications for poverty alleviation and addressing the problem of malnutrition in rural India.

Although the present study provides new insights and significantly contribute to our understanding of how traditional water bodies contribute towards livelihood improvement of poor and marginalized section of Indian rural society, the generalization of the findings may be difficult as the case is limited to a specific agro-climatic and ecological context. Hence, a follow-up study by including more agro-climatic zones and diverse ecosystems is necessary.

However, this study makes an important contribution to the existing knowledge because there is little information available on the economic valuation of the traditional water bodies especially in the context of India.