Wetland Utilization and Adaptation Practice of a Coastal Megacity: A Case Study of Chongming Island, Shanghai, China

Coastal urban areas are faced with risks induced by global warming and sea level rise, which puts pressure on regional sustainable development. In particular, land use adjustment is closely related to climate change for a coastal megacity. Coastal wetlands on the edge of the megacity represent a vulnerable ecosystem and a key area in terms of the resilient adaptation strategy. However, the interrelationship between the development of these wetlands and the megacity’s adaptation practice has not been sufficiently analyzed. From a historical perspective, based on document synthesis and field investigation, we attempt in this study to reveal long-term land use stages and driving factors in association with urban marginal wetlands, with a special reference to eastern Chongming Island, Shanghai. On such a basis, the future adaptation strategy of the megacity is evaluated. The analytical results show that this island has witnessed three periods of time for wetland utilization: traditional land use for salt production, fishery and agriculture before 1950, industrialization with rapid reclamation during 1950–2001, and the land use pattern orientated toward wetland ecosystem protection after 2002. The driving forces include sediment budget on the coast, wetland morphodynamic processes, sea level rise, population growth, and resource management policy changes. Transformation occurred between the wetland utilization stages in response to the changes of these forces. Furthermore, facing future climate change, there are different options of adaptation, e.g., retreatment and adherence. It may not be suitable for coastal cities with a large population to take the first option. It will be suitable for coastal communities to adhere to the location, if solutions to the problems of flooding risk, coastal erosion, and the maintenance of coastal facilities can be found. For eastern Chongming wetlands, as a key experimental area for ecosystem-oriented development in Shanghai, the transformation from the reclamation-oriented utilization toward the protection of wetland ecosystems represents the first step toward the latter option. We suggest that the next steps would be to maintain the ecological niche of the wetlands, to create new approaches to coastal engineering with contributions from the ecosystem, and to provide better ecosystem services.

Study on the status and effectiveness of coastal wetland utilization in Duy Xuyen district, Quang Nam province

This paper aims to assess the current status and effectiveness of coastal wetland utilization in Duy Xuyen district, Quang Nam province, and to propose solutions to improve land use and conserve the existing wetlands of the locality. Research results show that there are five types of wetlands in Duy Xuyen district: wetlands with tidal forests, streams, freshwater ponds, aquaculture ponds, and irrigated land. The wetland areas in Duy Xuyen district are mainly distributed in 3 communes: Duy Thanh, Duy Nghia and Duy Vinh and there is a noticeable decrease in the period from 2010 to 2016. The calculated results show that the total economic value of wetlands in the study area includes: direct use value is 41,276,949,000 VND/year (accounting for 99.61%), non-use value is 162,855,000 VND/year (accounting for 0.39 %). In which, the social and environmental economic values of wetland use types are totally different. Bài báo này nhằm mục đích đánh giá thực trạng và hiệu quả sử dụng đất ngập nước ven biển trên địa bàn huyện Duy Xuyên, tỉnh Quảng Nam, trên cơ sở đó đề xuất những giải pháp nhằm nâng cao hiệu quả sử dụng và bảo tồn diện tích đất ngập nước hiện có của địa phương. Kết quả nghiên cứu cho thấy, trên địa bàn huyện Duy Xuyên có 5 kiểu đất ngập nước: vùng đất ngập nước có rừng gian triều, sông suối, vùng nước ngọt, ao nuôi trồng thủy sản, đất được tưới tiêu. Diện tích đất ngập nước trên địa bàn huyện Duy Xuyên chủ yếu phân bố ở 3 xã: Duy Thành, Duy Nghĩa và Duy Vinh và có sự biến động giảm rõ rệt từ năm 2010 đến năm 2016. Kết quả điều tra cho thấy tổng giá trị kinh tế của đất ngập nước trên địa bàn nghiên cứu bao gồm: giá trị sử dụng trực tiếp (41,276,949,000 đồng/năm, chiếm 99.61%), giá trị phi sử dụng (chiếm 0.39% đạt 162,855,000 đồng/năm). Trong đó, hiệu quả xã hội và môi trường giữa các kiểu sử dụng đất ngập nước không đồng đều.

Seasonal and year-round use of the Kushiro Wetland, Hokkaido, Japan by sika deer (Cervus nippon yesoensis)

The sika deer (Cervus nippon yesoensis) population in the Ramsar-listed Kushiro Wetland has increased in recent years, and the Ministry of the Environment of Japan has decided to take measures to reduce the impact of deer on the ecosystem. However, seasonal movement patterns of the deer (i.e., when and where the deer inhabit the wetland) remain unclear. We examined the seasonal movement patterns of sika deer in the Kushiro Wetland from 2013 to 2015 by analyzing GPS location data for 28 hinds captured at three sites in the wetland. Seasonal movement patterns were quantitatively classified as seasonal migration, mixed, dispersal, nomadic, resident, or atypical, and the degree of wetland utilization for each individual was estimated. The area of overlap for each individual among intra-capture sites and inter-capture sites was calculated for the entire year and for each season. Our results showed that the movement patterns of these deer were classified not only as resident but also as seasonal migration, dispersal, and atypical. Approximately one-third of the individuals moved into and out of the wetland during the year as either seasonal migrants or individuals with atypical movement. Some of the individuals migrated to farmland areas outside the wetland (the farthest being 69.9 km away). Half of the individuals inhabited the wetland all or most of the year, i.e., 81–100% of their annual home range was within the wetland area. Even among individuals captured at the same site, different seasonal movement patterns were identified. The overlap areas of the home ranges of individuals from the same capture sites were larger than those for individuals from different capture sites (e.g., mean of annual home range overlap with intra-capture sites: 47.7% vs. inter-sites: 1.3%). To achieve more effective ecosystem management including deer management in the wetland, management plans should cover inside and outside of the wetland and separate the population into multiple management units to address the different movement patterns and wetland utilization of the population.

Density and diversity of birds in the wetlands of Yankari Game Reserve Bauchi Nigeria

The biological, chemical, and physical operations and attributes of wetlands are vital in facilitating food resources, water, and shelter, which many terrestrial bird and waterbird species rely on for their daily requirments. Wetlands in Yankari Game Reserve, Nigeria are key stone ecosystem that provides a stopover, breeding and/or foraging platform for migratory and resident birds. This study determined the density and diversity of birds in the wetlands of Yankari Game Reserve. Ten wetlands within the reserve were identified and surveyed. The sizes (kilometer square) and isolation distances (kilometer) of the wetlands were measured (using GPS and Map Source) to determine their effects on bird density and diversity. Point count survey method was used to count birds. One hundred and twenty three species of birds belonging to 51 families were recorded in the wetlands. Significant patterns in the densities of birds were observed across the wetlands (Kruskal-Wallis H, X2=167.116, P=0.001) and also sizes of wetlands (Wilcoxon test: Z= -2.803, P=0.005). There was differences in mean number of birds in survey time (Kruskal-Wallis, X2=15.784, P=0.045). Evenings were probably most preferred in bird-wetland utilization. Key words: Density; Diversity; Yankari ecosystem; Wetland utilization DOI: http://dx.doi.org/10.3126/jowe.v5i0.4778 J Wet Eco 2011 (5): 48-58