Dynamics Model Of Stubble Height And Stubble Weight And Sustainable Utilization For Biofuel In The Northeast, North, And Northwest Regions Of China

Field crop residue is renewable and sustainable organic resource, which has a huge number of sources and rich quantities. There is about750million tons production of field crop residue per year in China, which accounts for about25%of the world. The development and utilization of crop residue resources can promote the agricultural production, the efficient conversion and energy efficient cycle in the cropping system, and have become the indispensable important resources circulation in agriculture. Returning crop residue resource can effectively increase the content of soil organic matter, improve soil structure, reduce the applying fertilizer content, improve soil fertility, and also reduce farmers1production cost, which would be improve the farmland ecology, the elimination of air pollution caused by burning crop residue. It is of great significance to realize the sustainable development of agricultural. The statistical method and system engineering theory would be used in different varieties of the crop residue and utilization in this study, and the analysis of relational correlation model between available quantity and stubble height-stubble weight are carried on to promote theory basis on efficient utilization of field crop residue. Main research conclusion is as follows:1. The main crop type is different in six regions of China, which has the relation of the climatic conditions in each region, cropping system and crop growth characteristics. The ratio between plant height and aboveground dry matter has no direct correlation to different region, crop varieties. If the same stubble height when harvesting the crops was left, there is no significant difference between varieties with the ratio between the percentages of total crop residue (p<0.01). But there would be slightly different quantity between each variety, which also would not affect stubble weight in different region.2. It involves nine crops of maize, rice, wheat, soybean, sorghum, cotton, sunflower, canola, and oat from crop classification in this study. The results of the ratio between stubble height and stubble weight in the relational modeling are significantly correlated (P<0.01). And for different varieties of the same crop, the results analysis is the significant correlation without difference values (P<0.01).3. The average amount of total residue in NC (16.9Million ha) of83.0Mt (Mt=Mega tonnes) annually comprised of76.6Mt field residues and6.4Mt process residues. The average amount of total biomass residue in NEC (19.8Million ha) of105.7Mt annually comprised of92.8Mt field residues and12.9Mt process residues. In NC, the total standard coal equivalent (SCE) averaged for2010and2011amounted to46.4Mt, which comprised42.4Mt field residues and of3.9Mt process residues.In NEC, the standard coal equivalent (SCE) of57.0Mt comprised49.7Mt field residues and7.4Mt process residues on an air-dried basis. In the period between July-September, the amount of field residue available were40.9Mt (NC) and53.1Mt (NEC), respectively.In NWC, the average amount of total residue of59.8Mt annually comprised of55.0Mt field residues (91.9%) and4.8Mt process residues (8.1%). The standard coal equivalent (SCE) of33.4Mt comprised30.7Mt field residues and2.7Mt process residues on an air-dried basis. In June, September, and October, the amount of field residue (19.2Mt) was harvested.4. The amount of750million tons total filed crop residue was estimated in China between2010and2011. Annual311million tons of crop residue was returned, accounting for41.63%of the total crop residue. The sustainable availability of field crop residue could reach558million tons (74.35%), which could be used for sustainable utilization in China. According to this research, sustainable theory capacity returning to soil was192million tons (25.65%) of field crop residue, which can meet the sustainable utilization of soil.5. Three influence factors in grey correlation degree of available quantity of field crop residue were crop yields, effective irrigation area and the flooded area in thirty-one provinces of six regions of China.