Construction Of A Forest Ecological Network Based On The Forest Ecological Suitability Index And The Morphological Spatial Pattern Method

Forest landscape fragmentation and sharp area reduction are among the important reasons for the continuous decline of biodiversity.The construction of a forest ecological network model to identify priority areas for forest biodiversity conservation is an important method for maintaining forest biodiversity and provides technical support and a theoretical basis for sustainable forest management.Using Jindong Forest Farm as the study area,we used the Forest Suitability Index(FESI)and Morphological Spatial Pattern Analysis(MSPA)combined to identify core forest landscape patches,and identified ecological source areas using the patch importance index(dIIC,dPC);extracted ecological corridors using the minimum cumulative resistance model and gravity model;used ecological source areas as points and ecological corridors The forest ecological network model was constructed using ecological source areas as points and ecological corridors as edges;forest landscape network optimization measures were proposed,and the ecological network composite indices:α network closure,β line point rate and γ network connectivity were used to compare and evaluate the forest ecological network structure before and after optimization.The main research findings are as follows.(1)The FESI model was used to evaluate the suitability of the forest landscape;the forest landscape patches with high suitability levels were most prospectively subjected to MSPA analysis to determine the core patches;the landscape connectivity index was used to evaluate the connectivity of the core patches and determine the ecological source areas.The results showed that the minimum suitable habitat area,lower suitable habitat area,medium suitable habitat area,higher suitable habitat area and highest suitable habitat area accounted for 0.03,0.25,0.35,0.33 and 0.04 of the study area respectively.There are 345 cores,with an area of about 7,312.5 hm2,accounting for 38.5%of the suitable area;Edge,Perforation,Bridge,Branch,Islet and Loop account for 31.4%,1.21%,6.57%and 11.5%ofthe suitable area respectively.6.57%,11.5%,8.92%and 1.9%respectively.On this basis,11 ecological source areas were screened from the core areas through the analysis of the importance of connectivity.The results show that most areas of the Jindong Forest Farm are high suitability areas for forest resources,natural forests are mainly distributed within the ecological source areas,and the proportion of planted forests decreases as the importance of patches increases,and the FESI and MSPA methods can better identify ecological source areas than the tree species and area methods.The spatial morphological importance of patches is also taken into consideration along with the suitability of forest landscape patches,improving the subjectivity of the previous forest ecological network construction which only considered large forest patches as source patches.(2)The minimum cumulative resistance model was used to extract the minimum resistance path of the forest ecological network and remove the duplicate edges to obtain the potential ecological corridors;the interaction matrix was constructed based on the gravity model to calculate the interaction strength of each potential ecological corridor and quantitatively evaluate the priority of the potential corridors,and the forest ecological network model was constructed with the ecological source area as the point and the ecological corridor as the edge.The results show that the strongest interaction between patches 263 and 275 is 6186.85,and the smallest interaction strength between patches 284 and 163 is only 2.51.The potential corridors with interaction strength over 100 are taken as the ecological corridors of Jindong Forest Farm,and 54 forest ecological corridors are obtained.The results show that the corridors in the study area are mainly distributed in the central and southern parts,and that the overall spatial distribution of ecological corridors is uneven,and that new pedestal patches and ecological corridors should be planned rationally to enhance the overall connectivity of the forest ecological network in the study area.(3)By exploring the basic characteristics of the forest ecological network,the strategy adopted is mainly to follow the principles of sustainable development and add key ecological stepping stones and ecological corridors to improve network connectivity.By considering the dI values of the core patches and the actual situation of the study area,this paper suggests adding 10 ecological stepping stone patches and 24 ecological corridors,and connecting the supplementary source areas and ecological corridors with the original network to balance the layout of ecological sources and form a new ecological network.The new corridors run north-south in four parallel lines through the forest landscape ecology of the Jindong Forest Farm,making up for the difference in connectivity between north and south.The results show that after optimisation,the forest landscape ecological network structure indices α,β and γ of Jindong Forest Farm have increased from 0.49,1.86 and 0.67 to 0.55,2 and 0.7 respectively,and each index has increased to a certain extent,indicating that the forest landscape network structure has been fully optimised.