我国有机废弃物资源总量及养分利用潜力

  【目的】  我国有机废弃物产量巨大，理清我国有机废弃物总量及其养分资源量，有助于实现有机废弃物中养分资源的充分利用，对保障化肥使用量零增长和国家粮食安全具有重大意义。  【方法】  以我国2009—2019年间典型有机废弃物(秸秆、畜禽粪便、农村人粪尿、污泥和生活有机垃圾)的年产量为研究对象，通过查阅我国统计数据和公开发表的文献资料，对近10年我国有机废弃物总量及其养分资源量进行估算，分析有机废弃物利用潜力。  【结果】  2009—2019年有机废弃物资源量和养分总量相对稳定，平均有机废弃物总量(干重)为12.9亿t，平均养分含量(N、P₂O₅、K₂O)为4537.9万t。2019年废弃物资源量达13.11亿t (干重)，相比2009年增加7.1%；养分总量达到4503.5万t，相比2009年增加3.0%。2019年有机废弃物全量还田可以输入氮(N)约1653.3万t、磷(P₂O₅)约799.6万t、钾(K₂O)约2050.6万t，分别占作物养分需求量的71.8%、75.9%和153.2%。秸秆的氮和钾养分量最大，分别占有机废弃物中单质总养分的46.3% (N)和65.8% (K₂O)，磷养分量以畜禽粪便最高，占单质总养分的54.5% (P₂O₅)。  【结论】  我国近10年有机废弃物年产生量及其养分资源量保持较高水平，具有广阔的利用空间。在我国有机废弃物养分资源结构保持不变且全量还田的情况下，有机废弃物中的氮、磷、钾养分可以满足作物各类养分需求的71.8% (N)、75.9% (P₂O₅)、100% (K₂O)。

Organic waste resources and nutrient utilization potential in China

  【Objectives】  The production of organic waste in China is huge, so sorting out the total amount of organic waste and the amount of nutrient resources in China is pertinent for an optimum utilization of nutrient resources in organic waste, which is of great significance to ensure the zero growth of chemical fertilizer use and national food security.   【Methods】  From 2009 to 2019, estimation of nutrient resources and analysis of utilization potential were determined in typical organic wastes in China—straw, livestock manure, rural human manure, sludge, and domestic organic waste, using the statistics and published literature.  【Results】  The annual amount of organic waste resources and total nutrients was relatively stable from 2009 to 2019. The average total organic waste (dry weight) was 1.29 billion tons, and the average nutrient content (N, P₂O₅, K₂O) was 45.38 million tons. In 2019, waste resources reached 1.31 billion tons (dry weight), an increase of 7.1% compared with 2009. The total amount of nutrients reached 45.04 million tons, an increase of 3.0% compared with 2009. In 2019, the total amount of organic waste returned to the field contained about 16.53 million tons of N, 7.996 million tons of P and 20.51 million tons of K, accounting for 71.8%, 75.9%, and 153.2% of crop nutrient demand, respectively. The N and K contents of straw were the highest, accounting for 46.3% (N) and 65.8% (K₂O) of the total nutrients in organic waste, respectively. The P contents of animal manure were the highest, accounting for 54.5% (P₂O₅) of the total nutrients in organic waste.   【Conclusions】  The annual production and nutrient resources of organic wastes in China in the last ten years remain at a high level with a broad utilization potential. Under the condition that the nutrient resource structure of organic waste in China remains unchanged and the total amount of organic waste is returned to the field, nitrogen, phosphorus and potassium nutrients in organic waste can meet 71.8% (N), 75.9% (P₂O₅) and 100% (K₂O) of crop nutrient requirements.