闽东滨海湿地景观格局演化及其模拟

运用景观格局指数与马尔科夫模型分析了闽东滨海湿地1993、2001、2010年3个时期景观格局特征及动态变化,并引入分室模型模拟了3种人为干扰强度(干扰强度降低,干扰强度不变,干扰强度增强)下未来30 a景观异质性变化趋势。结果表明:20 a间闽东滨海湿地的总体景观格局变化微小,仍是以水域为基质,其他景观类型镶嵌其中的景观格局;受人类活动影响,天然湿地面积不断减少,人工湿地面积不断增加,但1993-2010年湿地总面积减少264.23 hm2,景观类型破碎化程度不断增加。水域、潮间裸滩和其他非湿地等自然景观大量转化为农田、建筑用地和养殖场,其中潮间裸滩面积不断萎缩,斑块数和斑块密度变化明显,斑块形状复杂度、分维数、破碎度和分离度也高于同时期其他景观类型。在3种不同强度的人为干扰下,闽东滨海湿地景观多样性呈现不同变化,高强度人为干扰将导致闽东滨海湿地景观多样性呈下降趋势。

Landscape pattern changes of coastal wetlands and its simulation in eastern Fujian Province

Landscape pattern characteristics and its changes from 1993 to 2010 in the coastal wetland of eastern Fujian Province,China were analyzed by landscape metrics.Changes tendency of landscape pattern during 1993-2001 and 2001-2010 were simulated by a markov model.Responses of landscape heterogeneity under three different scenarios(lower,present,and higher interference intensity of human activity) were analyzed through a compartment model in the next 30 years.The results obtained show that there is a little change on landscape pattern,and wetlands landscape fragmented processes are strengthened in the study area.Water is the matrix landscape,where other types of landscape are mosaic.The area of natural wetlands is declining while that of artificial wetlands is increasing due to impacts of human activity.The total area of coast wetlands decreases by 264.23 hm2 during 1993-2010.Waters,other non-wetland type and intertidal nude beach are strongly transformed into farmland,construction land and aquaculture ponds.Particularly,the area of intertidal nude beach is shrinking,with a significant change in terms of numbers of patch(NP) and patch density(PD).There are larger values of separation index(SI),fractal dimension(FD),fragmentation index(FN) in intertidal nude beach than other landscape types in the same period.Under three intensities of human interference present,landscape diversity in the coastal wetland has a different change obviously that the high intensity of human disturbance will make landscape diversity a sharp decline.