On the basis of an investigation on the mangroves in Fujian from November 1998 to January 1999, the species composition, area, distribution, artificial afforestation of mangroves and the factors restricting the develo...On the basis of an investigation on the mangroves in Fujian from November 1998 to January 1999, the species composition, area, distribution, artificial afforestation of mangroves and the factors restricting the development of mangroves in Fujian are discussed in the paper. Some suggestions on how to develop mangroves in Fujian have been put forward.展开更多
Studies on secondary production lead to a better understanding of the functions of the macrobenthic ecosystem.Basedon the macrobenthic data obtained at 6 sampling stations from April 2006 to January 2007,Brey's(19...Studies on secondary production lead to a better understanding of the functions of the macrobenthic ecosystem.Basedon the macrobenthic data obtained at 6 sampling stations from April 2006 to January 2007,Brey's(1990)empirical formula wasapplied to calculate the secondary production of macrobenthos in the mangrove area of Tong'an Bay.The results showed that themean annual secondary production of macrobenthos was 13.24 gAFDWm-2-a-1.The mean secondary production in the mangrovehabitat was 12.22 gAFDWm-2-a-1,lower than that in the non-mangrove habitat,which was 15.29 gAFDWm-2-a-1.Two possible rea-sons existed for this difference.First,mollusk and crustacean,which contribute more to the secondary production,probably benefitfrom longer inundation period in the non-mangrove habitat.Second,the higher organic matter in the mangrove habitat results in hy-poxia in the bottom sediment,which may decrease the secondary production.The annual mean production-to-biomass(P/B)ratio inTong'an Bay was 1.17,with a ratio of 1.27 in the mangrove habitat and 0.96 in the non-mangrove habitat,which was coincident withthe much higher density of Limnodriloides sp.and Corophium sp.in the mangrove habitat than in the non-mangrove habitat.Themaximum secondary production and P/B ratio of macrobenthos both appeared at sampling station FL2 in April,2006(namelyApril-FL2)with values of 31.38 gAFDWm-2-a-1and 2.20,respectively.The macrobenthic secondary production in Tong'an Bay islower than those in other intertidal studies except that in Haitan Strait,the reason being the different sediment properties.The P/Bratio in Tong'an Bay was the lowest due to the high proportion of crustaceans in the macrobenthic community.展开更多
Watamu Mida creek coastal areas, mainly the shoreline, the mangroves and the general environment have been changing due to the impact of land use change, shoreline erosion, human population pressure and the expansion ...Watamu Mida creek coastal areas, mainly the shoreline, the mangroves and the general environment have been changing due to the impact of land use change, shoreline erosion, human population pressure and the expansion of tourism sector. This research assesses the impact of land use change on mangrove dynamics and shoreline erosion as well as the main driving factors that cause these changes in Watamu Midacreek. This study uses old aerial photographs (1969 and 1989), current high resolution satellite images World view (2010) and ground truthing in combination with information from the local community to analyze the impact of change in land use from 1969-2010. Land use and cover types were visually interpreted, digitized and delineated using aerial photographs of 1969, 1989 and 2010 satellite images in ArcGIS.9.3.1 and ERDAS IMAGINE 2014 software. The results of the land use change between 1969 and 1989 showed a decline of scrub land, miscellaneous coastal vegetation, coastal bush, thicket with trees and mangroves, whereas new types of land use which emerged during this period were town and barren land. The greatest land use change rate observed between 1969 and 1989 was in miscellaneous coastal vegetation at 2.5%, while coastal bush experienced a significant negative change rate of 6.5%. The main land use changes observed between 1989 and 2010 were increasing coastal bush, an expansion of town and urban areas, hotels and private holiday houses. Encroachments into the mangrove forest have been observed both by local people and foreign private holiday house owners. The change in land use had an impact on shoreline changes as well. Areas mainly covered by old trees, and coastal bushes which protected the shoreline from erosion currently have been converted into very big hotels and several private holiday house complexes. The main drivers of land use change were human population growth and policy (through weakness of law enforcement). Policies and regulations which are not currently implemented need to be updated based on the current pressure-state situation, and there should be strong law enforcement and strict regulation to control any unplanned developments along the coast and in the neighboring hinterland.展开更多
文摘On the basis of an investigation on the mangroves in Fujian from November 1998 to January 1999, the species composition, area, distribution, artificial afforestation of mangroves and the factors restricting the development of mangroves in Fujian are discussed in the paper. Some suggestions on how to develop mangroves in Fujian have been put forward.
文摘Studies on secondary production lead to a better understanding of the functions of the macrobenthic ecosystem.Basedon the macrobenthic data obtained at 6 sampling stations from April 2006 to January 2007,Brey's(1990)empirical formula wasapplied to calculate the secondary production of macrobenthos in the mangrove area of Tong'an Bay.The results showed that themean annual secondary production of macrobenthos was 13.24 gAFDWm-2-a-1.The mean secondary production in the mangrovehabitat was 12.22 gAFDWm-2-a-1,lower than that in the non-mangrove habitat,which was 15.29 gAFDWm-2-a-1.Two possible rea-sons existed for this difference.First,mollusk and crustacean,which contribute more to the secondary production,probably benefitfrom longer inundation period in the non-mangrove habitat.Second,the higher organic matter in the mangrove habitat results in hy-poxia in the bottom sediment,which may decrease the secondary production.The annual mean production-to-biomass(P/B)ratio inTong'an Bay was 1.17,with a ratio of 1.27 in the mangrove habitat and 0.96 in the non-mangrove habitat,which was coincident withthe much higher density of Limnodriloides sp.and Corophium sp.in the mangrove habitat than in the non-mangrove habitat.Themaximum secondary production and P/B ratio of macrobenthos both appeared at sampling station FL2 in April,2006(namelyApril-FL2)with values of 31.38 gAFDWm-2-a-1and 2.20,respectively.The macrobenthic secondary production in Tong'an Bay islower than those in other intertidal studies except that in Haitan Strait,the reason being the different sediment properties.The P/Bratio in Tong'an Bay was the lowest due to the high proportion of crustaceans in the macrobenthic community.
文摘Watamu Mida creek coastal areas, mainly the shoreline, the mangroves and the general environment have been changing due to the impact of land use change, shoreline erosion, human population pressure and the expansion of tourism sector. This research assesses the impact of land use change on mangrove dynamics and shoreline erosion as well as the main driving factors that cause these changes in Watamu Midacreek. This study uses old aerial photographs (1969 and 1989), current high resolution satellite images World view (2010) and ground truthing in combination with information from the local community to analyze the impact of change in land use from 1969-2010. Land use and cover types were visually interpreted, digitized and delineated using aerial photographs of 1969, 1989 and 2010 satellite images in ArcGIS.9.3.1 and ERDAS IMAGINE 2014 software. The results of the land use change between 1969 and 1989 showed a decline of scrub land, miscellaneous coastal vegetation, coastal bush, thicket with trees and mangroves, whereas new types of land use which emerged during this period were town and barren land. The greatest land use change rate observed between 1969 and 1989 was in miscellaneous coastal vegetation at 2.5%, while coastal bush experienced a significant negative change rate of 6.5%. The main land use changes observed between 1989 and 2010 were increasing coastal bush, an expansion of town and urban areas, hotels and private holiday houses. Encroachments into the mangrove forest have been observed both by local people and foreign private holiday house owners. The change in land use had an impact on shoreline changes as well. Areas mainly covered by old trees, and coastal bushes which protected the shoreline from erosion currently have been converted into very big hotels and several private holiday house complexes. The main drivers of land use change were human population growth and policy (through weakness of law enforcement). Policies and regulations which are not currently implemented need to be updated based on the current pressure-state situation, and there should be strong law enforcement and strict regulation to control any unplanned developments along the coast and in the neighboring hinterland.
