Categorisation of land-cover and land-use adjacent to a Sri Lankan mangrove lagoon using object-based classification: state-of-the-art

This research deals mainly with the changes in land cover and their impact on the environment (the soil, the infiltration and drainage of water, evapotranspiration, flora and fauna) in and around Chilaw Lagoon, a Sri Lankan mangrove site. This requires research on the space-time dynamics in soil use and land cover to estimate and predict the human influences on the ecological changes. It examines how the fishing and the shrimp farms can (co-)exist on a sustainable manner in particular. A tool getting more and more crucial in the detection, description, quantification and observance of changes in the landscape and land use, is remote sensing (e.g. Dahdouh-Guebas et al., 2005a). In combination with geographical information systems (GIS) and field work, this is an effective management tool, particularly useful in the detection of ecological degradation (Dahdouh-Guebas et al., 2005b). It is very important to detect cryptic ecological degradation to mitigate loss of ecological functions, such as the protection function of mangroves (Dahdouh-Guebas et al., 2005c; Dahdouh-Guebas and Koedam, 2006). In addition, mangroves function as a source for timber and non-timber forest products for subsistence users, and as a nursery for numerous marine species (Ewel et al., 1998). Our research implements the following activities: (1) Characterisation of the actual land cover by means of remote sensing (Ikonos images) before the field work; (2) Verification on the field of the results of the image classification: land cover, land use, habitats, vegetation assemblages, individual species; (3) Field work on the vegetation structure; (4) Evaluation of the perception of the local population concerning the actual situation of the wood and fishery resources and in particular the cultivation of shrimps; and (5) By analysis of the image processing, the ecological footprint of the shrimp farms and the fishery, a calculation will be attempted of the area of the mangrove forests that are needed for a sustainable management of the shrimp farms and of the mangrove forests. There appears to be a conflict between the shrimp farms and the mangrove forests. One cuts down mangroves to build shrimp farms. But, on the other side shrimp farms cannot survive without mangroves because the gravid females used for stocking the shrimp ponds are dependent on the mangroves. A first expected result is an extensive classification of a very high Ikonos satellite image of Chilaw-Lagoon, with an interpretation key. This will give a good view on land cover and land use in the lagoon which will be used for land management. A second expected result is to give guidelines, based on the ecological footprint of shrimp farms, for reforestation of mangroves. And by this way to give a solution for the conflicts between adjacent land use. The research is ongoing, but this presentation discusses the state-of-the-art in the light of the above objectives and the expected results

Modelling mangrove propagule dispersal: sensitivity analysis and implications for shrimp farm rehabilitation

info:eu-repo/semantics/publishedHexennial International Conference ‘Meeting on Mangrove ecology, functioning and Management – MMM3’, 2-6 juillet, Galle, Sri Lank

Changes in mangrove vegetation area and character in a war and land use change affected region of Vietnam (Mui Ca Mau) over six decades

Aerial photographs and satellite images have been used to determine land cover changes during the period 1953 to 2011 in the Mui Ca Mau, Vietnam, especially in relation to changes in the mangrove area. The mangrove area declined drastically from approximately 71,345 ha in 1953 to 33,083 ha in 1992, then rose to 46,712 ha in 2011. Loss due to herbicide attacks during the Vietnam War, overexploitation, and conversion into agriculture and aquaculture encouraged by land management policies are being partially counteracted by natural regeneration and replanting, especially a gradual increase in plantations as part of integrated mangrove-shrimp farming systems. The nature of the mangrove vegetation has markedly been transformed over this period. The results are valuable for management planning to understand and improve the contribution of mangrove forests to the provision of ecosystem services and resources, local livelihood and global interest

Series expansions for a generalized xy hamiltonian .2. tricritical behavior of takagi model

The high-temperature series expansions for the square of the fluctuation in the order parameter, for the specific heat, the concentration and the concentration susceptibility for the Takagi model on an f.c.c. lattice are analysed in the field variables. We obtain for the critical exponent gamma = 4/3 and the specific heat is possibly logarithmically divergent. If we take the tricritical point to.be determined by gamma-t = 1, the tricritical exponents alpha-t, lambda-t and omega-t, are found to be consistent with 1/2.status: publishe

Impact of global warming on mangroves

info:eu-repo/semantics/nonPublishe