Abstract: The Taihang Mountains,Hebei Province was selected as study area for performance of early warning of ecological safety of land resources and quantitative measurement of impacts of various sensitive factors on outcome of the early warning using a fuzzy optimization model and a scenario analysis model.Results show that the warning of the land resources ecological safety in the study zone could be sorted into three levels,Yellow Alert,Blue Alert and Green Alert(of a five level alert system,green,blue,yellow,orange and red).The area was dominated by Blue Alert,which covered over 50% in acreage.On the time scale,the overall situation of the zone is improving slowly.And on the spatial scale,the middle section of the area has somewhat improved,but the north and south tips are getting serious,especially the latter.Ten sensitive factors(weighing factor>0.03) are the most important factors affecting the ecological safety in the study area.Their integrated contribution to safety of the whole ecological system should have aroused sufficient attention.In terms of contribution rate to the general system,the subsystems follow the order of status subsystem>pressure subsystem>response subsystem.So it is essential to regulate selectively the subsystems and the general system.

Key words: land resource, ecological safety, early warning, controlling, Taihang Mountains