中文摘要：

以广东省云勇林场火力楠人工林为试验对象,采取CK（对照）、施N、施P和施N＋P 4种处理,研究模拟氮和磷沉降对其土壤特性的影响。研究结果表明：加N显著增加了土壤全N、有效N、有效P和有效K含量,加P显著提高了土壤有机质、全N、全P、有效P和速效K含量,加N＋P提高了土壤有机质、全N、有效N、有效P和有效K含量;施N、施P和施N＋P 3种处理显著增加了土壤细菌、真菌和放线菌数量及脲酶和磷酸酶活性;加P处理还增加了土壤过氧化氢酶活性。

英文摘要：

Continuously increasing atmospheric N deposition and P fertilization profoundly influence forest soils. Changes in soil characteristics after simulating N and P deposition were studied in a Michelia macclurel plantation in Yunyong Forest Farm, Guangdong province to provide basis for soil management ofM. macclurel plantations. N and P addition was designed as ck, N addition, P addition, and N＋ P addition treatments. The results showed that N addition significantly increased soil total N, effective N, effective P and effective K contents; P addition significantly increased soil organic matter, total N, total P, effective P and effective K contents; N＋P addition significantly increased soil organic matter, total N, effective N, effective P and effective K contents. The N, P and N＋P addition treatments significantly increased the numbers of soil bacteria and fungi and actinomycetes, and activities of soil urease and acid phosphatase, and besides, P addition significantly increased catalase activity.