Experts at a discussion yesterday urged the government to restrict introduction of alien species of trees and animals into the biological diversity of the country as they harm biodiversity and agriculture. Mass awareness should be created along with the long-term plan to protect the biodiversity of the country, they added. The discussion was organised by Water Resources Planning Organisation (Warpo) to mark the International Day for Biological Diversity in the city with its Director General (DG) M Enamul Haque in the chair. This year's theme for the day was 'Biodiversity and Agriculture'. Two papers were presented on 'Biological Diversity' and 'Agriculture' at the discussion. Dr Nilufa Islam while presenting her paper on 'Biological Diversity' said biodiversity was endangered by introducing some alien species into the ecosystem of the country. She said, "Some species of both plants and animals that grow rapidly were brought in the country, but researches proved that those are harmful for the ecosystem in the long run. The alien species should be tested properly before their introduction into the ecosystem.' "Rapidly growing plants like Eucalyptus, Epil Epil and Akashia are harming the local species of trees, while introduction of Piranha and African Cat fish are killing the local species of fishes and genetically modified and hybrid paddy is harming the yields of local varieties of paddy,' she added. Environmentalist Mohammad Iftekhar Hossain while presenting his paper on 'Agriculture' said farming of crops, fishes and livestock should be conducted by local management to save the biodiversity. "By creating awareness among people, we can save our endangered species,' said Iftekhar. Speaking as the chief guest, Bangladesh Nature Conservation Centre President MRA Taha said protecting biodiversity of the country has no alternative to maintain its healthy environment and climate. Warpo DG said, "Renewable natural resources in a certain geographical area change with the change of seasons, but those can do a lot of damages to the environment and human life if alien species are introduced into that certain ecosystem.' The International Day for Biological Diversity is observed in 187 countries across the world according to a UN convention adopted in 1992. Bangladesh signed the convention on the same year and ratified that in 1994.