The status of pollinators and biodiversity in Asia: an overview

摘要

Asia has a large variety of climates and ecosystems with a wide range of plant and animal species. However, the pressures on the poor to meet their essential needs (food, fuel wood and fodder) and the elite's desire to accumulate wealth and maintainsocio-economic power are major factors causing the continuing destruction of forests and diminishing forest resources and their biodiversity to the extent of disrupting the ecological balance. Many forests are now fragmented which has resulted in lossesof many plant-pollinator relationships. However, forest fragments may still have adequate pollinator and plant diversity. The value of pollinators has been recognized since the dawn of agriculture, but measures for their conservation and management in wildlands have been considered only recently. The Rio Convention is instrumental for the conservation of pollinator biodiversity. India has identified pollination ecology as a major area for research and recognized the value of pollinators in conserving biodiversity. Detailed studies on pollination ecology and pollinators of agricultural and non-agricultural plants are being conducted to analyze the interactions between native pollinators and their native host plants. In Japan, populations of many species of native pollinators are declining or have become dependent on introduced plants as their native hosts disappeared. In urban areas, the greatest numbers of pollinator insects are in public gardens and parks with less plant diversity. Excellent work isbeing conducted in Israel to discover the roles of pollinators in maintaining plant diversity. Indonesia, Malaysia, China and other countries have pollination projects. Environment warming is influencing the reproductive cycles of pollinators. Pesticides, insecticides, etc. reduce the numbers of pollinator species. Pollinator numbers also decline due to losses of nest sites and native host plants through cultivation, urbanization and the burning of their habitats. The published information on pollination ecology of native species in Asia mostly comprises lists of pollinators of plant species, but does not provide information on the status of pollinator species in a study area or on the entire ecosystem of a region. Investigations on the status of pollinators must take into full consideration the importance of the sustainable availability of nest sites, the influence of climatic factors, etc. This information is required to plan measures for the effective conservation and management of pollinators ofwild plants and thus sustain biodiversity in natural and manmade habitats.