| Searching for a sustainable use pattern of mangrove resources is a premise of mangrove conservation in developing countries.Since 2005,uncontrolled domestic duck farming in mangrove forests has caused significant damage to mangrove forests and triggered discussions about the conservation and utilization of mangrove forests in China.To protect mangrove forests,Chinese administrators are considering a total ban of domestic duck farming in mangrove forests.Is domestic duck farming really in conflict with conservation of mangrove forests?At present,there is little scientific information on the various potential adverse effects of domestic duck farming on mangrove forests.This study conducted a comprehensive survey of domestic duck farming in the southern coastal areas of China,trying to find a mangrove-friendly domestic duck farming pattern.We aim to find a kind of domestic duck farming pattern that maximize economic returns from mangrove forests while maintaining the function of mangrove forests and to provide a basis for sustainable management.This work provided a new way to relieve the sharp contradiction between the conservation and utilization of mangrove forests.Duck farming provides opportunity for trade-offs between coastal ecology and economy.From 2011 to 2018,this study visited and investigated the main domestic duck farming villages and towns in Hainan,Guangdong and Guangxi,which accounted for more than 80%of the mangrove area in China.The situation has been repeatedly investigated,and some representative farmers(generally cultivated for many years,mainly through domestic duck farming to improve livelihoods)were visited,and the domestic duck species,breeding scale,breeding time,economic benefits and feed of domestic duck were recorded and comprehensively investigated.On this basis,we have determined four duck farming patterns according to whether the ducks are kept in captivity,the number and density of ducks:traditional farming,intensive farming(taking Dongzhaigang as an example),semi-intensive farming(taking Danzhou Bay as an example)and quasi-ecological farming(taking Qinzhou Bay as an example).The effects of intensive,semi-intensive and quasi-ecological three different domestic duck farming patterns on mangrove ecosystems were studied in order to find a pattern in which mangrove conservation and utilization coexist(where traditional farming has a limited effect on economic income,is limited to the self-sufficiency of the farmer’s family,and traditional farming in the mangrove area of China is not common.We only collect data on relevant economic profits).The main results are as follows:1.Different domestic duck farming patterns have different effects on mangrove forests.Intensive and semi-intensive farming patterns have severely damaged adult mangrove plants and seedlings,reducing the biodiversity of macrobenthos.The quasi-ecological farming pattern has less impact on mangrove forests and the influence on mangrove forests is controllable.2.Domestic duck farming can bring remarkable economic benefits to farmers.The annual income of intensive farming is 100,000 yuan,the annual income of semi-intensive farming is 80,000 yuan,and the annual income of quasi-ecological farming is 50,000 yuan.However,the return on investment of quasi-ecological farming(100%)was higher than intensive farming(40%)and semi-intensive farming(62.5%).3.According to the analysis of stable isotope and gastric contents of domestic ducks,the main food sources of quasi-ecological domestic ducks farming in Qinzhou Bay mainly include four categories:cereals,mollusks,crabs,and gravel.4.The culture capacity of the Dafeng River in Qinzhou Bay was estimated from the food source,and concluded that the culture capacity of the Dafeng River in Qinzhou Bay was 0.02 bird/m2.The culture capacity of quasi-ecological farming in Qinzhou Bay is 0.015 bird/m2,which is smaller than the culture capacity of Dafeng River in Qinzhou Bay.Therefore,the impact of quasi-ecological farming on mangroves is controllable and a sustainable utilization pattern.This study shows that although the intensive farming pattern has significant economic benefits,it has been proved to cause great damage to mangrove forests and should be explicitly prohibited.According to the provisions of Article 20 of the Regulations on Natural Reserves in Hainan Province(2011),it is forbidden in Hainan.Domestic duck farming is carried out in the mangrove nature reserve in Hainan Province.Uncontrollable domestic duck farming has caused enormous damage to mangrove forests and is unsustainable.It needs to be taken seriously by relevant departments,especially in Danzhou Bay and Xinying Bay.The quasi-ecological farming pattern is a sustainable utilization pattern of mangrove forests,which can not only protect mangrove forests well but also increase the economic income of farmers.In areas where ecological tourism cannot be carried out,non-nature reserves can be properly carried out and cannot be easily banned.However,further research is needed on the farming pattern and culture capacity to find a balance between ecological protection and economic development. |
