| 英文摘要 |
Dashu Old Railroad Bridge Constructed Wetland is located under the Old Railroad Bridge on the right bank of Gaoping River in Dashu District, Kaohsiung City. With an area covering 100 hectares, this wetland is the largest constructed wetland and natural ecological water park in southern Taiwan. The site was flooded by Typhoon Morakot on 8 August 2009 and lost its original function of water purification. Both the wetland environment and ecology also suffered grievous destruction. Collective reconstruction and restoration efforts by the government and local volunteers of the Old Railroad Bridge wetland ponds and environmental landscapes were completed on March 2011. The park has remained operative since then. The main draining source of System A comes from the second grade effluent processed by Yuen Foong Paper Co., Ltd. paper mill. Effluents first pass through the A1 inlet by gravity flow before entering System A. For System B, drainage from the Zhuliao Creek is separated into two. Part of the drainage flows into B1 pond and then enters the wetland system by gravity flow before its final discharge from the outlet into Gaoping River. The following provides the results of this project as of 31st December 2014:
(1) Investigation and Monitoring of Wetlands Sites and Boundary
Environments
Hydrological measurements for this project were conducted during 2014. Major survey sites include the inlets and outlets of System A and System B within the site in order to understand the hydrological information of System A and System B. As of 31st December 2014, 3 water quality monitoring, 3 hydrological measurements, 2 sediment monitoring, and 2 ecological investigations have been conducted for this project.
1. Average monitoring results of the hydrological measurements in 2014 indicated that for System A and System B, volume of water processed were 9,346m3/d (7,033 - 10,835 m3/d) and 1,632 m3/d (1,418 - 1,937 m3/d) respectively; total water volumes were about 96,436 and 1,128 m3 respectively; outflow volumes were around 4,608 (3,024 - 5,616 m3/d) and 1,318 m3/d (1,212 - 1,371 m3/d) respectively; hydraulic loadings were 0.10 and 0.32 m/d respectively; hydraulic retention time were 10.8 and 0.7 days respectively.
2. Results of water quality monitoring showed that the overall trend for dissolved oxygen (DO) was 3.6 - 6.6 mg/L with an average of 4.2 mg/L, of which the gravel contact oxidation system outflow has the highest DO level. Results of biochemical oxygen demand (BOD) monitoring indicated that the annual average inflow and outflow concentrations were 46.5 and 7.5 mg/L, respectively, for System A, 27.3 and 15.1 mg/L, respectively, for system B, and 32.9 and 20.2 mg/L, respectively, for the gravel contact oxidation system. For total phosphorus (TP), inflow and outflow concentrations were 0.154 and 0.102 mg/L, respectively, for System A, 0.154 and 0.102 mg/L, respectively, for System B, and 1.276 and 1.018 mg/L for the gravel contact oxidation system. The gravel contact oxidation system had the highest inflow TP concentration. For ammonia nitrogen monitoring results, inflow and outflow concentrations were 0.4 and 0.1 mg/L, respectively, for System A, 1.3 and 1.1 mg/L, respectively, for System B, and 3.3 and 0.1 mg/L, respectively, for the gravel contact oxidation system. For chlorophyll-a monitoring results, inflow and outflow concentrations were 57.2 and 17.2 μg/L, respectively, for System A, 50.5 and 36.4 μg/L, respectively, for System B, and 102.7 and 29.0 μg/L, respectively, for the gravel contact oxidation system. Escherichia coli monitoring results indicate that wetland processing has reached a certain degree of bacterial removal. Annual average inflow and outflow concentrations were 7×106 and 8×105 CFU/100mL, respectively, for System A, 4×106 and 5×105 CFU/100mL, respectively, for System B, 1×107 and 4×105 CFU/100mL, respectively, for the gravel contact oxidation system.
The 2014 water quality monitoring results revealed that the average removal effectiveness of total pollutants was 27% - 99% for System A, 17% - 88% for System B, and 20% - 100% for the gravel contact oxidation system. Surface water body was almost rated as grade IV due to the relatively high BOD levels.
3. Results of sediment monitoring revealed an average organic matter content of 0.4 - 5.0%; average TP of 308 - 592 mg/kg; and average total nitrogen (TN) of 615 - 1,245 mg/kg. Of the 8 types of metals monitored, Fe had the highest concentration at 26,861 mg/kg in 2014, which was lower when compared to the 38,493 mg/kg in 2013. Wetland dredging has been carried out in May 2014, which resulted in a decrease in the average content of various metals.
4. Across the three sample areas, a total of 31 families and 61 species of birds, 4 families and 5 land species of terrestrial reptiles, 4 families and 6 species of amphibians, 5 families and 46 species of butterflies, 3 families and 17 species of dragonflies and damselflies, 3 families and 3 species for aquatic reptiles, and 11 families and 16 species of fish have been recorded over the years. Investigations on plant ecology have recorded 54 families and 128 species. Of these 128 species, 58 (45.3 %) were non-native plant species that have been introduced. According to the investigations, current records of birds showed that there were more bird species in the southern area of the Old Railroad Bridge, with the northern area having fewer species but greater variability. For other species, the number of species from the sample area underneath the Old Railroad Bridge was fewer than that of the other two areas. Currently, species compositions in these sample areas were still in a state of disturbance and instability. Moreover, invasive amphibian, reptile, and fish species have been found as well. Introduced species seemed to have gained dominance in the water bodies. We recommend catching invasive fish species by angling and netting before their breeding season.
During the breeding season, the fish larvae may be collected by netting. For the policy of increasing biodiversity in the Old Railroad Bridge Wetland, initial stages may include increasing the species and areas of wetland scrubs in order to provide habitats for birds and butterflies.
(2) Results of Wetland Seed Teacher Training and Public Guides
Currently, the project implementation team has joined forces with various civil groups (such as the Kaohsiung City Old Railroad Bridge Association, Dashu Culture and History Association, and tile kiln associations), communities (Chuliao Community Development Association and Chiutang Community Development Association and others), schools (Chiuchu Elementary School, Dashu Junior High School, Fooyin University, Shu-Te University, National Sun Yat-sen University, National Pingtung University of Science and Technology and others) in the neighboring areas in order to jointly implement various tasks such as wetland maintenance and management, provide tours and guides, and seed teachers training.
1. Wetland Conservation, Management and Maintenance
Collective efforts of community members and local volunteers have helped implement the management and maintenance of the Old Railroad Bridge Wetland Park. A total of 6 maintenance and management operations across at least 24 sites was required. As of 31st December, a total of 32 management and maintenance sessions have been carried out, meeting the project objective of at least 24 sessions (sites). A total of 596 individuals participated in the management and maintenance activities. Community associations and volunteers from civil groups have actively participated in wetland conservation as well as management and maintenance operations, removing weeds, fallen leaves, large tree branches and garbage from the Park areas. The maintenance personnel and volunteers have also actively promoted the trash off the ground principle. Hence, no trash bin has been placed in the park with the hope that the public could develop the habit of taking trash home and keeping the environment of the Wetland Park neat and tidy. The quality of the Park environment has been praised by many tourists, making the Park the perfect place for various activities organized by public agencies, public and civil businesses, and schools.
2. Educational Training Workshops of Wetland Management and Maintenance Unit
The Old Railroad Bridge Wetland Park has a total area of 100 hectares. It has been hoped that education and training of organizations responsible for Park maintenance will help local volunteers and community members understand and learn about wetland maintenance and management strategies in order to enhance the trainees' capabilities and knowledge in supporting future wetland management and maintenance operations. Contractual terms state that 12 sessions of educational training workshops shall be provided for the wetland management and maintenance units. As of 31st December, 12 training sessions have been held with a total of 434 training participants, thereby successfully achieving the required project progress. A number of trainees have participated in actual management and maintenance of the site, and assisted students from colleges, junior high schools and senior high schools in volunteer experience activities.
3. Trainings for Wetland Conservation Seed Teachers and Instructional Guides
Neighboring community development associations and civil groups have been involved to jointly participate in tour guide trainings for the Old Railroad Bridge Wetland Park. These trainings could help develop seed instructors for tour guides to facilitate subsequent educational and promotional programs in schools and other units. According to contractual requirements, a total of 14 training sessions were required. As of 31st December, 14 sessions have been held for a total of 437 participants. The trained seed instructors have gained the capability of acting as a wetland tour guide and have visited neighboring junior and senior high schools to promote wetland conservation courses.
4. Public participation in Wetland Park ecology and environmental education and instructional guides
Seed teachers and volunteers have provided tour guides for the Old Railroad Bridge Wetland Park, led participating members of the public to personally experience the functions of ecological conservation and environmental education for constructed wetlands and explained how the wetlands purify water as well as the roles of the animals and plants in the wetlands. Contractual terms stipulate that at least 2 batches and 12 sessions of public instructional guides must be provided every month. By 31st December, 39 sessions have been held, achieving the 35 sessions required of the schedule, with a total of 1286 enthusiastic participants. Instructional guides described in this section were mainly provided by the trained seed instructors who had given actual instructional guides before in order to apply knowledge learned in class in their actual work.
5. Audio-visual Records of the Course of Wetland Reconstruction
Audio-visual records of wetland environmental education and ecological conservation of the Old Railroad Bridge Wetland Educational Park have been compiled in order to help the public and tourists appreciate the results of the transformations brought about by the constructed wetland, benefits environmental maintenance and management, environmental education, and ecological conservation. By 31 December 2014, post-production processes such as editing and dubbing have been completed to generate a preliminary draft which was then submitted to your agency for reviewing. Once approved, the master copy shall be sent to a specialized factory for encoding and burning. A total of 100 VCDs of the audio-visual records shall be made. For this year, the records were primarily presented in the form of micro movies and aerial photography, providing a comprehensive and faithful recording of this year's results of wetland conservation, management and maintenance, educational workshops and instructional guide training, and environmental education and instructional guiding of the Old Railroad Bridge Wetland Park.
|