Comparing waterbird communities of four types of fish ponds before and after drawdown in winter
| Autor: | LI, CHANG-CHENG, 李昶誠 |
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| Rok vydání: | 2017 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 105 Due to nature habitats were destroyed, waterbirds instead use artificial wetlands to be alternative habitats, like rice fields and salt pans. The alternative habitats become more and more important, artificial wetlands have part nature habitats function, can provide wintering waterbirds for foraging and resting. Through the management of wetlands, can provide a variety of foraging habitat, and can attract large and diverse waterbird communities for foraging. Study site is located Chiku, Tainan area, at the experimental fish ponds of National University of Tainan Chiku Campus. There are four types of fish ponds: A) wild fish species without feeding, B) tilapia with feeding, C) milkfish with feeding and D) tilapia without feeding, all of the fish ponds were shallow aquaculture. The results showed that each fish pond had significantly higher waterbirds species and densities when drawdown. Utilization of waterbirds having significantly differences of water depth of preferences. The Cluster results showed that the waterbirds were divided into three groups: mudflat, shallow water and deep water. The majority of the waterbirds were mudflats and shallow water, and the number of the deep water group was the lowest. There were no significant differences in waterbird families using the four types of fish ponds, but the milkfish pond had most utilized by waterbirds in this study, it accounted for 59.8% of the waterbirds. When fish ponds maintain the water level at average of 20 cm, and let it natural dry, waterbirds can sustainable utilize more than 1 month, the max amount of peak will appear less than 2 weeks, then gradually reduced. The average cost of milkfish cultivation of raw materials is about 45,000 NT/ha.This cultivation can provide utilization for waterbirds with an average of 849 individual/ha and for black-faced spoonbills 56 individual/ha. Reducing water levels does provide a rich source of food for waterbirds, and it is recommended that future policies to promote waterbird conservation can encourage aquaculture operators to reduce water levels and provide good foraging habitats. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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