长春地区食物链氮素养分流动趋势与特征分析

氮素养分管理问题一直是国内外关注的热点。论文通过整理统计资料和文献数据,利用NUFER（Nutrient Flows in Food Chains, Environment and Resources Use）模型,研究了长春地区1993—2013年食物链的氮素流动趋势特征,旨在为该地区氮素的优化管理和相关政策制定提供参考。研究结果表明：1993年长春地区食物链系统氮素的总输入量为26.4×10⁴ t,至2013年增长至50.8×10⁴ t;食品生产方面,动物性食品的氮素流量由1993年的0.7×10⁴ t增长至2013年的2.3×10⁴ t,而植物性食品氮素流量则由7.1×10⁴ t减少至6.7×10⁴ t;食品消费方面,动、植物性食品氮素流量分别由1993年的0.5×10⁴和3.3×10⁴ t增长至2013年的1.4×10⁴和3.6×10⁴ t。20 a间,长春地区食物链各环节的氮素养分利用率均呈下降趋势,其中畜禽和作物生产系统的氮素利用率分别由14.5%和56.1%降至13.2%和48.0%,整个食物链系统的氮素利用率由16.9%下降为10.6%,而与此同时氮素的损失率则由38.2%提高为48.7%。可见,随着经济发展和社会变革,长春地区食物链系统的氮素流动量大幅增加,而氮素利用效率则大幅下降。现阶段,该地区农牧生产和家庭消费中应注意含氮废弃物的管理与循环利用,减少氮素损失,从而提高利用效率。

The Trend and Characteristics of Nitrogen Nutrition in the Food Chain in Changchun

Nitrogen nutrient management has been a hot topic in the world. Nowadays, the way of evaluating nitrogen nutrient management from the perspective of food chain has attracted much attention. However, most of the researches are mainly confined to the longitudinal flow of the food chain, and the research on the whole nutrient flow of the food chain is more helpful to provide guidance for the rational management and allocation of nitrogen. This study aims to provide a theoretical basis for the optimization of nitrogen management in Changchun area. Based on the NUFER model, the trend characteristics of nitrogen flow in the food chain from 1993 to 2013 in Changchun area was studied by collating literature and statistics data. The results showed that the total input of nitrogen increased from 26.4×10⁴ t in 1993 to 50.8×10⁴ t in 2013 in food chain system in Changchun. In the food production aspect, the nitrogen flow of animal-derived food increased from 0.7×10⁴ t in 1993 to 2.3×10⁴ t in 2013, however, the nitrogen flow of plant-derived food decreased from 7.1×10⁴ t in 1993 to 6.7×10⁴ t in 2013. In the food consumption aspect, the nitrogen flow fluxes of animal-derived food and plant-derived food increased from 0.5×10⁴ t and 3.3×10⁴ t in 1993 to 1.4×10⁴ t and 3.6×10⁴ t in 2013, respectively. Over the past twenty years, the nutrient use efficiency of the food chain showed a downward trend, and the nitrogen utilization rates of the animal production system and crop production system decreased from 14.5% and 56.1% to 13.2% and 48%, respectively. The nitrogen use efficiency of the combined system of agriculture and animal husbandry was reduced from 29% to 17%. The nitrogen utilization rate of the whole food chain system decreased from 16.9% to 10.6%. The nitrogen loss rate of the food chain system increased from 38.2% to 48.7%. It can be seen that with the economic development and social change, the nitrogen flow in the food chain system in Changchun area increased significantly, while the nitrogen use efficiency decreased significantly. Recently, it should be noted nitrogenous waste management and recycling in the food chain system, reduce nitrogen loss and improve efficiency.