He Zhongqi, Honeycutt C Wayne, Griffin Timothy S, Cade-Menun Barbara J, Pellechia Perry J, Dou Zhengxia
USDA-ARS, New England Plant, Soil, and Water Lab., Orono, ME 04469.
J Environ Qual. 2009 Jul 23;38(5):1909-18. doi: 10.2134/jeq2008.0445. Print 2009 Sep-Oct.
Organic dairy production has increased rapidly in recent years. Organic dairy cows (Bos taurus) generally eat different diets than their conventional counterparts. Although these differences could impact availability, utilization, and cycling of manure nutrients, little such information is available to aid organic dairy farmers in making nutrient and manure management decisions. In this study, we comparatively characterized P in organic and conventional dairy manure using solution and solid state (31)P NMR spectroscopic techniques. Phosphorus in both types of dairy manure was extracted with water, Na acetate buffer (100 mmol L(-1), pH 5.0) plus 20 mg Na dithionite mL(-1), or 0.025 mol L(-1) NaOH with 50 mmolL(-1) EDTA. Solution NMR analysis revealed that organic dairy manure contained about 10% more inorganic phosphate than conventional dairy manure. Whereas organic dairy manure did contain slightly more phytate P, it contained 30 to 50% less monoester P than conventional dairy manure. Solid state NMR spectroscopy revealed that mono-, di-, and trivalent metal P species with different stabilities were present in the two dairy manures. Conventional dairy manure contained relatively higher contents of soluble inorganic P species and stable metal phytate species. In contrast, organic dairy manure contained more Ca and Mg species of P. These results indicate that P transformation rates and quantities should be expected to differ between organic and conventional dairy manures.
近年来，有机乳制品生产迅速增长。有机奶牛（Bos taurus）的饮食通常与传统奶牛不同。尽管这些差异可能会影响粪便养分的有效性、利用率和循环，但可供有机奶农进行养分和粪便管理决策的此类信息很少。在本研究中，我们使用溶液和固态（31）P NMR光谱技术对有机和传统奶牛粪便中的磷进行了比较表征。两种类型的奶牛粪便中的磷均用水、醋酸钠缓冲液（100 mmol L(-1)，pH 5.0）加20 mg连二亚硫酸钠mL(-1)或含50 mmolL(-1) EDTA的0.025 mol L(-1) NaOH进行提取。溶液NMR分析表明，有机奶牛粪便中的无机磷酸盐比传统奶牛粪便多约10%。虽然有机奶牛粪便中的植酸磷确实略多一些，但其单酯磷比传统奶牛粪便少30%至50%。固态NMR光谱显示，两种奶牛粪便中存在具有不同稳定性的一价、二价和三价金属磷物种。传统奶牛粪便中可溶性无机磷物种和稳定的金属植酸盐物种含量相对较高。相比之下，有机奶牛粪便中含有更多的钙和镁磷物种。这些结果表明，有机和传统奶牛粪便中的磷转化率和数量应该会有所不同。
