Study On The Agriforest Models Of Tree-Poultry-Grass Ecosystem In Northern Anhui

Based on the economical principle of ecological circle and the strategy of forest and agriculture sustainable development,this paper used the research methods such as agroforestry,density controlling and circular cultivation to solve the problems existing in northern Anhui province,which mainly include large population and less land,structural monotony of forestry and agriculture,heavy pollution caused by the livestock manure and lack of theoretical basis for the compound management.This paper analysed the mutual influence among all the elements in the ecological compound,breeding pattern of forestry-poultry-grass according to the structure and function of forest and tree,the coverage of herbal plants below the tree,the quality of poultry products,breeding density,proper cultivation circle.The goal of this paper is to find out the optimal ecological compound breeding pattern and management measures of combination of forestry and poultry in northern Anhui region.The main conclusions are as follows:（1）The mixed forest of different deciduous and evergreen tree species has significant positive effects on the temperature and humidity of forest land,the wind speed,the light intensity,the amount of negative oxygen ions（P<0.05）,the index of forest environmental comfort is at its best（<4.55）.All of this is favorable for the growth of poultry and vegetation in the forest,which guarantees the environmental demand on the balanced development of the elements in compound pattern,thus creating a favorable condition for the management of the“forestry-poultry-grass”compound pattern.（2）The mixed-forest of deciduous trees has an outstanding improved effects on the physical and chemical properties of the land（0-20cm）when the breeding density is 40 per mu（0.164 acre）（P<0.05）.Specifically,moisture content increased by 4.27%while soil bulk density decreased by 0.28g.cm^-3,which is equal to the18.8%of the previous one.Porosity increases by 5.3%and the increased on the amount of total nitrogen,total phosphorus and total potassium in the soil was 43.8%,27.3%and 21.8%respectively,while increase on the amount of organic material,available nitrogen,available phosphorus,available potassium was 14.9%,1.7%,10.8%and1.4%respectively.Meanwhile,it also has an significant effect on the increase of the height of the tree and the spotted area of the herbal vegetation below the tree.（P<0.05）.（3）The mixed wood of evergreen trees has an outstand improved effects on the physical and chemical properties of the land（0-20cm）when the breeding density is30-40 per mu.Specifically speaking,moisture content increases by 4.25%,3.17%while soil bulk density decreases by 0.11g.cm^-3,0.18g.cm^-3,which is equal to the7.1%,11.7%of the previous one respectively.Porosity increases by 10.7%,5.2%respectively.However,when the breeding density is set to 40-per mu,the results is not favorable as the one in the condition of 30 per mu,mainly shown on the growth of vegetation below the tree and the chemical effects on the soil.When the breeding density is set to 30 per mu,the increase on the amount of total nitrogen,total phosphorus,total potassium in the soil is 28.6%,5.6%,27.9%respectively,while increase on the amount of organic material,available nitrogen,available phosphorus,available potassium is 14.6%,1.6%,7.5%,2.7%.In the meanwhile,there has been a huge improved effect on the increase of the height of the tree and the spotted area of the herbal vegetation below the tree.Therefore,the appropriate breeding density for the evergreen hybrid forest is 30 per mu.（4）In the deciduous trees containing hybrid forest,when the breeding circle is set to 30 days and 60 days,fresh grassby the chicken was 3.5 and 3.1times respectively larger as compared to the 90-day breeding circle,under which the decrease of the standing crop and coverage rate of the grassland is the greatest,that was 57.9%and 68.1%respectively.The manual labor was more in the 30-day breeding circle as compare to the 60-day breeding circle.However,in the deciduous trees containing hybrid forest,when the breeding circle is set to 30 days and 60 days,the consumption of the fresh grass by the chicken was 3.2 and 1.8 times larger compared to the 90-day breeding circle,under which the decrease of the standing crop and coverage rate of the grassland is the greatest,77.8%and 82.8%respectively.While under the condition of 30-day breeding circle,the decrease of above two index is the lowest and the consumption of the fresh grass by the chicken was the largest,all of which made it distinct from the 60-day and 90-day breeding circles.In conclusion,the appropriate breeding circle for the hybrid forest of deciduous trees and hybrid forest of evergreen trees was 60 days and 30 days respectively.（5）Although the influence on the nutritional value of the chicken meat of wild chicken of the forest was not distinct,the texture and taste of the chicken meat was far better than the chicken breeding in the poultry farms.The quality of the egg yolk of the former was higher than the latter,so was the color and other nutrition.This showed that poultry breeding in the forest has a huge impact on the quality of the egg.All in all,the price of the chicken products breeding in the forest is higher,thus resulting in better economic benefits.