Study On The Optimization Between Ecological And Institutional Networks Of Water Systems In A Quanfuzhuang Small Watershed Of Hani Rice Terrace Region

For the sustainable existence of the Honghe Hani Rice Terraces Heritage Site,a world cultural landscape heritage,water is the key resource and the irrigation system of draining and irrigating corridors or facilities is the key pattern.Irrigation system includes two network patterns of natural ecology and social management,and the former provides the foundation and the later plays a key regulatory role.How to characterize the ecology-management network pattern of irrigation system and propose optimization scheme has become a hotspot in socio-ecological landscape researches and related disciplines.This paper takes Quanfuzhuang small drainage system in Hani Terrace area as the research object,and takes the geospatial data and the questionnaire survey as the data sources.It uses the drainage pattern index,the network index and the minimum cost model to obtain the ecological network characteristic,uses the social network analysis method to obtain the governance network characteristics and an optimized model,and uses the common pool resources self-governance pattern analysis method to obtain the irrigation water governance rules and the influence.Finally,it puts forward water system management suggestions for the studied area based on the above three aspects.The research enriches the research methods and cases of ecological and governance network,and provides scientific basis for the sustainable development of Hani terraces and the work of related departments.The main conclusions are as follows:(1)Identification of the ecological network of the drainage system: The drainage pattern and structural connectivity of small-drainage rivers and ditches are superior to those of rivers or ditches;its number of important nodes and corridors for functional connectivity is large,mainly distributed in the eastern region;its potential ecological corridors are composed of arbor forests,grassland/shrubs and terraces(main landscapes)as well as traffic land and rural residential land(key landscapes);the degrees of action among water patches are greatly varied,and primary and secondary key corridors,key nodes and breaking points play a key role in water resources distribution.(2)Identification and optimization of the drainage governance network: The governance nodes and contact lines of small-drainage rivers and ditches are dense in the northeast and loose in the southwest.They show the spatial structural characteristics of center-transit-divergent radiation;the strength of connection,direction,density,central potential and centrality are greatly varied;the core area are mainly distributed in the eastern,northern and northwestern radiation areas,the marginal areas are mainly distributed in the middle-western,southwestern and southern radiation areas,and there is an obvious boundary retarding effect between them;cohesive subgroups are formed in eastern,northern,western and southern areas,respectively in source,center,developing or unformed stage;its optimization is cored by “seven centers,thirteen cores,five horizontals and seven verticals”.(3)Rules and management of irrigation system in Quanfuzhuang small watershed.Based on Ostrom public pond resource theory,this study defined the water resource boundary,users' boundary and management boundary.The ownership of users,division of management and collective sharing rules and action arrangements of water resources in different regions are analyzed.Analyzed the mechanisms of supervision and sanction and the solution to conflicts in irrigation,and the irrigation management rights among farmers,ditch leaders,water conservancy commissioners,village team leaders,villagers' assemblies,village committees and other governance organizations.From the perspective of the Ostrom's eight principles and the COX12 principle,this study analyzed the interrelationships and action mechanisms between irrigation water management rules,and further explored the interaction between villages and townships and other higher-level governance organizations and the impact on water patterns.Based on the Partition morphology and distribution characteristics of the key nodes and corridors of the ecological network of irrigation system,the joint nodes of social management,the key nodes and corridors of water resources management,the corresponding management principles and recommendations are proposed.