| To clarify the distribution pattern and characteristics of straw and livestock manure in Sichuan province in recent years, and provide scientific basis for the resource utilization of agricultural waste in Sichuan province, this study discusses the potential and ways of recycling straw and livestock manure in each county, and uses spatial analysis to study the distribution and aggregation areas of straw (rice, wheat, maize and rapeseed) and livestock manure (cattle, sheep, pig and poultry) resources in Sichuan province, which based on the county scale production of major crops yield and livestock output in Sichuan province in 2018. The results showed that :(1) The total amount of collectable straw (rice, wheat, maize and rapeseed) in Sichuan province in 2018 was 28085.5 thousand tons, with the distribution showing the pattern of ‘one center, dense in the east and sparse in the west’, and the straw types were mainly maize and rice. In 2018, the total amount of livestock manure in Sichuan province was 81620.2 thousand tons, with the distribution showing the pattern of ‘three centers, dense outside and sparse inside’, pig manure occupies the absolute dominant, accounting for 57.8%. (2) In 2018, the fertilizer application of annual straw production in Sichuan province could theoretically save 7.4% of nitrogen fertilizer and 5.0% of phosphate fertilizer input in this province, and the total potassium could meet the amount of potash fertilizer in this province. Energy utilization of straw can be converted into 14.2271 million tons of standard coal or 6.22×109 m3 biogas. In 2018, the total fertilizer utilization of livestock and poultry manure in Sichuan province could save 42.6% of nitrogen fertilizer input, and the total phosphorus and total potassium in livestock and poultry manure could meet the consumption of phosphorus and potassium fertilizer in Sichuan province. Energy utilization of livestock and poultry manure can be converted into 8.3519 million tons of standard coal or 4.15×109 m3 methane. (3) There were 30, 40 and 48 straw hotspot counties in 99%, 95% and 90% confidence intervals respectively, with the amount of straw in the hotspot counties accounting for 39.4%, 49.5% and 56.3% of the total amount of straw in the province, respectively. There were 23, 31 and 37 livestock manure hot spots counties respectively, and the proportion of livestock manure in hotspot counties to the total amount of livestock and poultry manure in the province was 24.4%, 33.9% and 38.8%, respectively. The Chengdu plain and the hilly areas of eastern Sichuan have been the key areas for straw and livestock manure resources enrichment and recycling in Sichuan province in recent years. The pure straw and livestock manure hot spots counties can have their own emphases when considering the utilization pattern of them, and the 21 straw-livestock manure hot spots counties can consider the combination of planting and raising mode, and implement multi-level and diversified utilization pattern. |
