| As the concept of sustainable development being widely accepted by publics, more andmore environment problems have arose deeply rational thinking. Eyes are focused onhealth. Forest is a main ecosystem on the land, its health directly relate to humans' existand living. Being theoretic immature, the concept of ecological health hasn't beenpopularly applied on forest management at macro scale as to landscape. The paper regardsforest landscape health theory as a new management method, a process-orientedmanagement modes on ecology safety. The newly defined theory was practiced on forestlandscape management located on the upper reach of the watershed of Miyun reservoir,which is one of the most important water resources for the capital Beijing. Meanwhile, it isa re-inspection of forest management in past several years. Conclusions are drawn asfollowing:Landscape has health characters like organism. Landscape ecological health is not only astate free from ecological-synthetic-threaten, but also a complete state of structure andfunction. It is a synthetic assessment on structure and pattern, biophysical process and theecological services of landscape. Structure and pattern health prefers to describe theecological integrity of landscape components and their spatial pattern, biophysical processhealth describes the condition of inherent ecological process within or among mosaics andecological service health emphasizes the landscape capability of providing satisfiedecological services in terms of energy recycling, material moving and information transfer.An ecological healthy landscape must have optional structure and pattern, efficientlyprocess and needed ecological services.Landscape ecological health is composed of many factors as to forest, wetland,rangeland, farmland, civil-land and oceans. As forest landscape health is concerned, we arefar behind of our colleagues out-broad whether in achievements or technology. Ecologicalhealth for forest landscape includes two points: the first is for itself about its favorable stateon components integrity, fundamental functions. The second is its satisfaction ability forsocial economy development.Landscape health have ecological scales, therefore, its standard must be multi-scaled,dynamic and relative. However, being short of long-term ecological monitoring materialand process mechanism study, to building a reasonable standard is a hot and intractableproblem. On the ecological point of view, the author did the assessment on the state offorest landscape from three aspects, by selecting 40 index around its organize, vigor,productivity. Then, the dynamic assessment standard have been build on scales oflandscape patch, landscape type and region separately for the health state of "very well","well", "sub-well", "lightly sick" and "sick".Forest landscape in this watershed can be identified on three classes. At the first class,forest accounts for 67.33 percent, forming the dominant landscape type. The second classhas been identified by predominance tree in each patch, conifer-broadleaf mixed forestonly takes 12.22% of the 11 forest landscape types, and commercial forest make the largestportion. By the manage aim and needed functions, the third class has been defined asecological-oriented, ecology economical-oriented and economy ecological-oriented types.The precision for classification results is over 80 percent.The average area of forest landscape patches is 8.9hm2 with a variation of 195.04.Within forest landscape types, the area of Roburs is the biggest, the Pinus is the biggest inneedles. The mean perimeter is 17.3m, mean edge density is 1.94m/hm2, mean patchdensity is 0.11. The diversity index of forest landscape is 2.6391, evenness index is 0.6884,dominance index is 0.6817.The process of natural evolvement has been studied. From the positive slope to thenegative slope, as the soil and moisture getting better, the species distributing modechanges from collective to patches or dispersed, and the number, the diversity, the evennessincrease, the ecological dominance decrease.On energy cycle, the net radiation Pinus and Acacia received is 45-71% and 55-80% ofthe total radiation respectively. The soil thermal flux is 10-20% and 23%, and the storedthermal flux is 1.2% and 0.9%. The maximum energy cost of evaporation for Pinus andAcacia is 69.2% and 58.8%.On water cycle, the canopy interception rate of Pinus and Acacia is 26.59% and 9.97%.As to the maximum water holding, the Bass-broadleaves forest and Birch forest reaches thehighest value of 5.70mm and 5.10mm. The maximum evaporation and transpiration ofPinus and Acacia is 0.146mm/h and 0.334mm/h separately. The eliminate ratio of surfaceflow is 60.4% for Pinus, and 76.9% for Acacia. The soil infiltration ratio of each kind offorest landscape is bigger than barren slope contrasted and the mountain poplar, the Birchforest with more humus and better physical structure has better infiltration than others. Thesaturation water contain of all forest land is averagely 1.73-3.62 times of barren slope.On soil moving, the erosion of each kind of forest land is lower than fell ruins. Withlarger rainfalls, the ratio of soil prevention increases together.On nutrient cycle, the Acacia, Pinus and commercial trees show a coherent ability ofN absorbing and congregating, which means they are all short of N element.The average biomass is 7.6t/hm2 in this area, and the maximum and minimum valuesare occupied by broadleaves and arborvitae. The productivity is not high, especially forarbors, which are far below of the average level of Beijing area. As a whole in thiswatershed, the evaporation and transpiration is 66.48% of inputting precipitation, thecanopy interception owns 14.82%, soil infiltrates 8.6%, surface flows 1.71% and soilcontains 7.22%. Therefore, forest has the typical functions of elimination on surface flow,and the main ways of water loss is evaporation and transpiration.After rainfalls pass through the canopy of Acacia or Pinus, the content of K elementincreased notably, which is almost 37.44 times and 26.61 times of that in the air. And thetotal elements content in the trunk flow is 4.13 times and 5.11 times of that in the air. Whenwater samples pass through soils of Acacia forest land, Pinus forest land and commercialwoodland, the total elements content increased 11.7 times,10.1 times and 5.6 times of each.The monitoring results of lower groundwater and rivers show a typical adjustment functionof forest ecosystem on chemical element moving with water.By the combination methods of Analytical Hierarchy Process and Fuzzy mathematics,the state of forest landscape health is analyzed. The result is the holistic state for forestlandscape is partially sub-healthy, and the structure of most of forest landscape issub-healthy, the process is healthy and the ecological service is sub-health. The reason forthose may caused by large area of barren and wasteland and shrubland located in thisregion, simple canopy structure, poor landscape diversity, low proportion of mixed forestand many fragment patches in artificial forest. The integer function of forest landscape didnot run well.The simulation of Marcov model on the trend of landscape pattern indicate that, infuture 10 or 20 years, forest coverage rate in this watershed shall reach 70% around, thestate of forest landscape shall be improved with optimized structure inside.Hydrological adjustment service is prognosticated based on SWAT model, whichshow that in the same climate, the capacity for water containing goes up with increasingvegetation coverage, and it will get better and better in the future.The strategies for forest landscape state improvement was established finally,including spatial pattern adjustment, inherent structure reformation and serviceoptimization. The author suggests that, researches on landscape ecological health,well-bred selection and combined afforestation techniques, directional restore of naturalvegetation digital forest and monitoring on ecosystem should be emphasized. And also,some foster jobs should be strengthened. The government shall encourage communities toparticipate in the management of forest landscape oriented to water resource protection.
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