Assessing the economic and nutritional value of pollination services in Nepal

Abstract

Pollination is a key ecosystem service crucial for supporting agricultural production, economic growth, social inclusion, and environmental protection. Understanding the economic value of pollination and its impact on human health and nutrition is essential for effective pollinator conservation and management. This study evaluates the economic and nutritional value of pollination services in Nepal and quantifies historic changes in pollinator reliance. Using public data on agricultural production and commodity prices, in combination with published nutritional composition values, we employ the dependency-ratio method to quantify economic and nutritional value across different regions of the country and through time. We conservatively estimate the annual economic value of pollination services in Nepal at US $477 million, representing 9% of total agricultural revenue. Pollinator-dependent crops, particularly fruits and vegetables are the source of essential nutrients; 40% of plant-based vitamin A and 14% of vitamin C are directly attributable to insect pollination. The cultivated area of these pollinator-dependent crops has increased by 91% in Nepal over 20 years - 3.7 times faster than equivalent increases in non-pollinator-dependent crops. The decline in wild pollinators during the same time period poses a threat, leading to potential pollination deficits and crop losses. Our study underscores the importance of conserving and managing pollinators to ensure sustainable agriculture, food security, and nutrition. Targeted efforts, including policy interventions and conservation strategies, are needed to safeguard pollinator populations and enhance pollination services.

Fig. 1

Map of Nepal showing the seven provinces.

Fig. 2

Clustered heat map that displays the Total value of Crop (TVC) across provinces in columns and crop category in rows. B Clustered heat map that displays the Economic value of Insect Pollination (EVIP) across provinces in columns and crop category in rows. C Clustered heat map that displays the Total value of Crop (TVC) across provinces in columns and Pollination dependence in rows. The hierarchical cluster analysis utilized the UPGMA method and Euclidean distance measurement following the standardization of the average scores (using the decostand function with the range method in R).

Fig. 3

Percentage of total plant-based nutrient production attributable to animal pollination for each of 14 key dietary nutrients derived from crops grown in Nepal.

Fig. 4

Heatmap showing the proportion of each key nutrient produced in each of the seven provinces. Provinces are ordered from lowest (left) to highest (right) total nutrient production.

Fig. 5

Heatmap showing the vulnerability of each key nutrient to pollinator loss, separated by province. Nutrients are ordered from highest (top) to lowest (bottom) pollinator dependence.

Fig. 6

Historical trends in (a) cultivated area and (b) production of crops in Nepal. Crops are divided into categories depending on their degree of pollinator dependence.