Benefits Valuation Of Eucalyptus-Crops Agriforestry

Agroforestry is a ancient farming way. The process that the various economical factors, environmental factors and social factors harmonize continuously in the system is basic process of agroforestry's development. It can ensure the sustainable development of agroforestry that the three greatest benefits of economy, ecosystem and society harmonic development.For establishing the eucalyptus-crops agroforetry of high productivity and good comprehensive benefits, eucalyptus-crops agroforetry have cultivated at Leizhou forestry bureau , Hainan Jinhua forestry and Guangxi shenglin Forestry with broad strip mode. Through eucalyptus-crops agroforetry management, to make use of the environment resources to agriculture production well, and at the same time to ensure the wood production not output reduction. On this foundation, carrying on the benefits valuation to eucalyptus-crops agroforetry, they are expected to be the theories of the eucalyptus-crops agroforetry spreading.5 years to be a management period and sugar cane to be the intercrop, there are 21 modes which broad strip is 8m, 10m, 12m, 14m, 16m, 18m, 20m, tree distance is 0.5m, 0.8m, 1m and narrow strip is 1.3m. In this research, carrying on the analysis and valuations to the economic benefit , soil improvement benefit and social benefit of eucalyptus-crops agroforetry. On the base of available research results, horizontal comparison analytical method was used to the valuation. Conclusions below:1,Research of eucalyptus yield and inter-sugarcane yield show that ecalyptus yield of these modes that eucalyptus plant density more than 1500 per hectare would not lower than traditional mode 1.67×4m, these modes are suited for eucalyptus-crops agroforestry. The modes that broad strip more than 16m and tree distance between 0.8-1m are suited for eucalyptus-sugarcane agroforetry management. In these modes sugarcane yield would not lower than normal level. The modes that strip stance between 8-16m can used to produce these crops that not need more light, such as Stylosanthes gracilis, kinggrass etc..2,Eucalyptus-crops agroforetry can reduce the forestry production cost, it's good for eucalyptus management. One side eucalyptus-crops agroforetry can reduce the forestry nurture cost, including loose soil, weeding under trees and applying fertilizer to eucalyptus. On the other side, some forestry production cost can share with intercrop, such as land plough cost, land rent etc.. To compare the forestry production cost of eucalyptus-crops agroforetry with forestry, the lowest can reduce 339.66yuan/ hm2(mode 8×0.5m), the most is 5577.81yuan/hm2(mode 20×1m).3,During the economic benefits evaluation, indexes including profit rate of cost, net income, profit rate of investment, profit and tax rate of investment, payback period of investment, NVP and IRR were used. The result showed that the modes which broad strip more than 16m and tree distance between 0.8-1m come to better economic benefits, and have greater ability to against indeterminate economic risk, and higher pay taxes ability. Eucalyptus-crops agroforetry can do greater contribution for the society.4,The soil improvement benefit is been evaluated in eucalyptus-crops agroforestry. Fertilizer put into intercrop and agriculture wastes return can increase the soil nutrient in eucalyptus-crops agroforetry. It's good for soil sustainable use. Through estimation, after a sugarcane intercrop farming season, the economic values of add soil nutrient is 17757.67yuan/hm2. The sugarcane leaf is to be the agriculture wastes to return farmland, conservative estimation for the economic values of the soil N, P, K complement between 655.01—4108.35yuan/hm2.5,Eucalyptus-crops agroforetry can increase land utilization rate. In a management period, land utilization rate average increment between 19.36%-67.58% each year, and the system also can increase multi-cropping index of land. More employment opportunities are supplied to society by eucalyptus-crops agroforetry. Through estimation, they can supply employment opportunities between 634-1379 day/hm2 in a management period. In a management period , eucalyptus-crops agroforetry has crops output each year, more than two productions supply to society. Eucalyptus-crops agroforetry can do greater contribution for society.The studies indicated that eucalyptus-crops agroforestry has good economic benefits and social benefits. The system is good for soil sustainable use. Eucalyptus-crops agroforetry has wide applied value and broad development prospects.