Coastal Wetland Landscape Pattern Dynamics And Its Vulnerability Assessment Feature In Eastern Of Fujian Province

This paper studied on the landscape pattern, dynamic and driving force of coastalwetlands in Eastern of Fujian Province based on remote sensing and GIS. We usedtheories and methods of landscape ecology to make researches such as landscapeclassification of the coastal wetlands, coastal wetlands pattern, evolution mechanismof coastal wetlands in the past20years, simulation of the evolution trend in the next30years (by the Markov model and the compartment model), the driving force oflandscape change mechanism, vulnerability assessment of coastal wetland ecosystemsand sustainable use of ecological regulation and control strategy. The main resultswere following:(1)The coastal wetland landscape classification system in Eastern of FujianProvince was established. Drawing on previous researches and combining with thewetland features in the field, we considered the hydrology, geomorphology, andmatrix factors in order to establish a three-level classification system, including2firststage classification,4second classification and7third classification which includedthe waters, intertidal bare beach, artificial reservoirs and ponds, farmland, farms, andother non-wetland landscape and building land.(2)We studied the coastal wetland in landscape patterns, dynamics andmechanism of the driving force, in1993,2001and2010. The results showed that, thewater landscape was the matrix landscape of the Mindong coastal wetland,for it wasthe largest area proportion, the most stable shape and the best connectivity throughoutthe landscape. On the number of patches, the artificial wetlands had the largestnumber of patches; intertidal bare beach patch had maximum patch density and a highlevel in the fragmentation index, separation, and patch shape index. This illustratedthat this types of wetlands had been sustained the most intense human disturbancesand a high degree of fragmentation. The overall landscape pattern changes little in thestudy area, still based on water as a matrix landscape, other landscape typesmosaicked it, in the past20years. The area of the natural landscape types declinedand fragmentation index increased; the area proportion of water declined from 57.491%in1993fell to55.182%in2010; the intertidal bare beach constantlyincreased in fragmentation index, only lower to the artificial ponds, in the past20years; the artificial landscape types in the area was a substantial increase, and farmsarea ratio increased largest, from4.338%in1993to6.21%in2010, and its patchdensity increased from0.2146one hundred block/km2to0.3317one hundred block/km2; the main driving force which affected the landscape pattern change most wasman-made factors; demographic factors, industrial restructuring and reclamation ofcoastal reclamation were the main reasons.(3)The results of Markov model analysis show that the waters, othernon-wetland landscape type and intertidal bare beach were a large number convertedto farmland, construction sites and farms; the waters still had the highest retentionrates,intertidal bare beach kept the lowest rate and was reclamation to farmland andfarms in a large number. Compartment model simulation results show thatanthropogenic interference made the coastal landscape diversity increased, but thehigh intensity of human disturbance will have the diversity of coastal wetlands insharp decline.(4)EVI of coastal wetlands in Mindong was0.4706, belonged to the moderatelyfragile. This showed that wetland landscape structure was fairly complete; but thenatural state had a certain changed; vitality deterioration and functional level had acertain degradation; and the resilience of outside interference was weaken. Along withPSR model, the ecologically fragile of the study area was mainly caused bypopulation pressure and economic factors. The degradation characteristics of coastalwetlands was lower degree of resilience, wetland ecosystem degradation, the abilityof resistance to outside interference weakened, water demand reduced and pollutionload index increased and the wetland function is declining(5)Based on the system research of coastal wetland landscape and vulnerabilityassessment, we constructed a kind of wetland landscape spatial structure whichincluded nature reserve, landscape ecological function zone and wetland ecologicalpark. And according to the specific circumstances coastal areas in the eastern Fujian,we proposed two recommendations about the sustainable development. In addition, the study also showed that the most effective means in recovery and reconstructionwas recovered the wetlands vegetation, removed invasive species and returned theland to the nude beach intertidal and sea.