Energy Analysis Of Village Landscape Ecosystem And Its Sustainability In The Hilly Area Of The Middle Sichuan Basin

The Xinqiao village in Jintang is one of the representative villages in the hilly area of the middle Sichuan basin. The whole village landscape was mapped with the techniques of 3S on the basis of IKONOS' high resolution (1m) remote sensing imagery. The characteristics of energy flow of the landscape were analyzed, related to the agricultural sustainability. The main results are showed as following:1 , Total input-output energy ratio has been arrived about 1.471. The ratio of energy output to input in the subsystem of plant is 1.488, which is lower than the national level (1.963). The average energy input of paddy and dry-land per 666.7m except for winter paddy is 83% higher than the national level and the energy output except for summit is registered a 69% increase. The photo-utilization efficiency of the plant subsystem is 0.788%, which is a high level compared with Chinese ecological agriculture demonstrations (0.5-0.98%).2, Biological supplemental energy is 2.3 times industry supplemental energy. Fertilizer energy input is 91 per cent of total energy input, and occupies the absolute advantage, techniques energy input is very low, and only occupies 4 per cent or so. The input-output energy ratio of farmland ecosystem has remarkably negative relationship with organic fertilize energy input, so energies of ecosystem are wasted.So, the rational region of energy input per 666.7m2 is confirmed to 5.5-12.14GJ in current village landscape ecosystem. The grain single output comes to the higher level when the amount of chemical fertilizer energy input is 1.88GJ, and the amount of organic fertilizer energy input is 5.32GJ.In whole village households about 37% input energy excessively, so energies about 440GJ are meaninglessly put into environment .It equaled to 4.78 tons pure nitrogen or 32.86 tons P205.3, Farm landscape fragmentation is 0.002515, which means to 666.7m2 arable landwas cut apart 1.7. With the increasing of number of arable land, the farm landscape separation degree increased. The disperser the farm lands become, the more the land numbers are. Analysis on the system energy flow characteristic indicated the longer the distance between farmer and his plot is, the smaller the energy input is. Therefore, the yielding economic energies per 666.7m2 are lower. The energy flow efficiency of system is depressed because of the separation and fragmentation of arable land.4, It should be improve land concentrative degree properly in order to arrange land resource rationally and realize agriculture sustainable development. If it keeps up appropriate space centering on household house and within the radius between house and arable land, times shouldn't exceed 20 minutes unit.5, Some feasible approaches of landscape configurable adjustment are put forward according to possibility analysis of village population development and distributing over staffed, evaluation on landscape energy input benefits and landscape suitability. That is, in view of assuring farmer realize comparatively good living standard, all the summit and partial slope bench plateau ecotope (about 325-473 666.7m2) should be changed over forest (grass) landscape or other non-yielding landscape. The landscape configurable adjustment, this new idea was imported agriculture sustainable development.