Toth John D, Dou Zhengxia, Ferguson James D, Galligan David T, Ramberg Charles F
Section for Animal Production Systems, School of Veterinary Medicine, Univ. of Pennsylvania, 382 West Street Rd., Kennett Square, PA 19348, USA.
J Environ Qual. 2006 Oct 27;35(6):2302-12. doi: 10.2134/jeq2005.0479. Print 2006 Nov-Dec.
Management of animal manures to provide nutrients for crop growth has generally been based on crop N needs. However, because manures have a lower N/P ratio than most harvested crops, N-based manure management often oversupplies the crop-soil system with P, which can be lost into the environment and contribute to eutrophication of water bodies. We examined the effects of N- vs. P-based manure applications on N and P uptake by alfalfa (Medicago sativa L.), corn (Zea mays L.) for silage, and orchardgrass (Dactylis glomerata L.), leaching below the root zone, and accumulation of P in soil. Treatments included N- and P-based manure rates, with no nutrient input controls and inorganically fertilized plots for comparison. Nitrate concentrations in leachate from inorganic fertilizer or manure treatments averaged 14 mg NO(3)-N L(-1), and did not differ by nutrient treatment. Average annual total P losses in leachate did not exceed 1 kg ha(-1). In the top 5 cm of soil in plots receiving the N-based manure treatment, soil test P increased by 47%, from 85 to 125 mg kg(-1). Nitrogen- and P-based manure applications did not differ in ability to supply nutrients for crop growth, or in losses of nitrate and total P in leachate. However, the N-based manure led to significantly greater accumulation of soil test P in the surface 5 cm of soil. Surface soil P accumulation has implications for increased risk of off-field P movement.
为作物生长提供养分的动物粪便管理通常基于作物对氮的需求。然而，由于粪便的氮磷比低于大多数收获作物，基于氮的粪便管理往往会使作物-土壤系统中的磷供应过量，这些磷可能会流失到环境中，导致水体富营养化。我们研究了基于氮和基于磷的粪便施用对苜蓿（紫花苜蓿）、青贮玉米（玉米）和果园草（鸭茅）氮磷吸收、根区以下淋溶以及土壤中磷积累的影响。处理包括基于氮和基于磷的粪便施用量，设有无养分输入对照和无机施肥地块用于比较。无机肥料或粪便处理渗滤液中的硝酸盐浓度平均为14毫克硝酸根氮/升，不同养分处理之间没有差异。渗滤液中年平均总磷损失不超过1千克/公顷。在接受基于氮的粪便处理的地块土壤表层5厘米处，土壤有效磷增加了47%，从85毫克/千克增至125毫克/千克。基于氮和基于磷的粪便施用在为作物生长提供养分的能力以及渗滤液中硝酸盐和总磷损失方面没有差异。然而，基于氮的粪便导致土壤表层5厘米处土壤有效磷积累显著增加。表层土壤磷积累意味着场外磷迁移风险增加。
