The economic value of ecological regulating services provided by agricultural insects in China

Society has recognized the value of ecosystem services. Insects are one of the most diverse groups, playing a significant role in maintaining ecosystem function and ecological balance, and fulfilling human demands. Insect ecological services are the functional roles in ecosystem processes, benefiting humans with goods and services such as pollination, pest control and decomposition. Insect ecological services include provisioning, regulation, cultural and support services. The economic value of insect ecological services can be divided into direct-, indirect-, option- and existence values. The ecological regulating services of insects involve pollination, biological control and dung burial. Insects perform pollination services to crops, vegetables and fruits which are an important ecological service. Pollination is usually the transfer of pollen from the male sex organ to the receptive portion of the female sex organ in flowering plants. Insect pollinators are adapted to many flowering plant species and are provided with primary rewards that attract (i.e., “attract and reward”) and establish pollen vectors returning to flowers. Rewards include nectar, pollen, lipid secretions, food bodies, scents, resins, and material for nest building. Biological control is a particular type of pest control, resulting in predatory/parasitoid insects suppressing pest densities to relatively low levels. This type of ecologically based pest management infers that the “natural enemies” control the pest species. The types of natural enemies used for biological control vary depending on the type of pest. The decomposition of organic matter and the recycling of carbon are provided by beetles that bury dung. Dung beetles process a substantial amount of the animal dung that has accumulated in ecosystem. Dung beetles are medium to large-sized beetles specializing in feeding and breeding on an ephemeral and discrete food resource, consisting mainly of the dung piles produced by herbivorous warm-blooded animals. The dung beetles provide regulating services that reduce forage fouling, nitrogen volatilization, parasites and pest flies. Humans could not persist without these insect provided services. Estimating the value of ecological services provided by insects may help establish a higher priority for their conservation. This paper discusses the concept and categorization of insect ecosystem services, including an economic evaluation of those services. In 2007, insect pollination, pest control and dung burial values were estimated using agricultural production data from China. The results indicated that the insect regulating service value for pollination was 6790.30×108 yuan RMB, accounting for up to 54.05% of the total value of pollinator serviced crops. The value of pest control from natural enemies was 2621.00×108 yuan RMB, which was up to 9.09% of the total value of the crops serviced. The value of dung burial was 90.84×108 yuan RMB. The total insect regulating service was valued at 9502.14×108 yuan RMB, accounting for up to 3.7% of China's GDP (2007). These results show the annual value of insect regulating service in an agroecosystem are similar to the economic values of grassland or forest ecosystem services in China. The accurate valuation of insect ecological services is critical to establishing and preserving the ongoing development of insect-based resources and biodiversity in China. © 2015, Ecological Society of China. All rights reserved.