养分添加对亚热带常绿阔叶林土壤养分状况的影响

分类号： 单位代码： 10364 密 级： 学 号： S 安徽农业大学学位论文养分添加对亚热带常绿阔叶林土壤养分状况的影响Effects of N and P addition on soil nutrient in a subtropical evergreen broad-leaved forest研究生： 赵 阳 指导教师： 徐 小 牛 教授 申请学位门类级别： 农 学 硕 士 专业名称： 森 林 培 育 研究方向： 生物地球化学循环 所在学院： 林学与园林学院 答辩委员会主席： 2013年6月独 创 性 声 明本人声明所呈交的论文是我个人在导师指导下进行的研究工作及取得的研究成果。尽我所知，除了文中特别加以标注和致谢的地方外，论文中不包含其他人已经发表或撰写过的研究成果，也不包含为获得安徽农业大学或其它教育机构的学位或证书而使用过的材料。与我一同工作的同志对本研究所做的任何贡献均已在论文中作了明确的说明并表示了谢意。研究生签名： 时间： 年 月 日关于论文使用授权的说明本人完全了解安徽农业大学有关保留、使用学位论文的规定，即：学校有权保留送交论文的复印件和磁盘，允许论文被查阅和借阅，可以采用影印、缩印或扫描等复制手段保存、汇编学位论文。同意安徽农业大学可以用不同方式在不同媒体上发表、传播学位论文的全部或部分内容。(保密的学位论文在解密后应遵守此协议)研究生签名： 时间： 年 月 日第一导师签名： 时间： 年 月 日课题来源本研究得到下列科研项目资助：国家“973”计划项目(2010CB)国家自然科学基金项目（）摘 要土壤是植物生存的重要环境因子，也是森林生态系统研究的重要组成部分。一方面，森林土壤可为森林植被的存在和发展提供必要的物质基础；另一方面，森林植被的出现及其演替反过来也将影响其土壤的形成和发育。随着人口增加、经济发展和环境变化对土地资源的压力日益增大，导致土地退化和污染十分严重。目前，土壤质量是制约全球生物圈可持续发展的重要因素之一，亦是生态环境、土壤管理和土地利用的可持续评估、判断准则。土壤是森林生态系统营养元素转化的重要枢纽，其养分状况影响林木生长，使森林生态系统表现出不同的生产力水平。 在氮沉降全球化的背景下，研究和预测氮沉降对我国森林生态系统的影响及其反馈，对于制定合理的经济发展战略、制订森林资源和环境管理计划和提高应对全球变化能力均具有重要理论价值和实践意义。鉴于此，于2011年1月在安徽查湾自然保护区选择亚热带常绿阔叶林建立了永久性的试验样地，通过养分添加试验（氮添加、氮磷添加），探讨氮磷添加对亚热带常绿阔叶林土壤养分状况的影响，为揭示森林土壤养分动态及其对氮沉降增加的响应机理提供基础。研究结果显示，养分添加前表层 0-10 cm土壤pH (H2O)平均值为4.28、pH (KCl)的平均值为3.34，电导率（EC）的均值为200.47 Scm-1，全氮的均值为3.13 gkg-1，全钾的均值为9.52 gkg-1，全钙的均值为83.22 gkg-1，全镁的均值为1.70 gkg-1，全磷的均值为176.03 mgkg-1。不同处理各养分之间差异不显著（p0.05）。 养分添加后，对照（CK）样地表层 0-10 cm土壤中，铵态氮含量最高出现在2012年6月（11.05 mgkg-1），最低在2011年12月（3.60 mgkg-1）；氮添加（N）处理样地分别出现在2011年10月（14.64 mgkg-1）、2011年9月（4.90 mgkg-1）；氮磷添加（N+P）处理，则分别在2011年8月（17.24 mgkg-1、2011年9月（4.90 mgkg-1）。10-20 cm土层中，对照铵态氮含量最高在2011年8月（19.16 mgkg-1），最低在2011年12月（2.50 mgkg-1）；氮添加分别出现在在2011年8月（11.67 mgkg-1）、2011年7月（3.41 mgkg-1）；氮磷添加分别在2011年8月（15.45 mgkg-1）、2011年7月（2.97 mgkg-1）。表层0-10 cm土壤中，对照硝态氮含量最高在2012年2月（1.65 mgkg-1），最低在2011年12月（0.17 mgkg-1）；氮添加分别在2011年10月（22.51 mgkg-1）和2012年4月（0.17 mgkg-1）；氮磷添加分别在2011年10月（7.14 mgkg-1）和2012年4月（0.18 mgkg-1）。10-20 cm土层中，对照硝态氮含量最高在2011年7月（1.43 mgkg-1），最低在2011年10月（0.35 mgkg-1）；氮添加分别在2011年10月（10.08 mgkg-1）和2012年4月（0.18 mgkg-1）；氮磷添加分别在2011年10月（4.11 mgkg-1）和2012年4月（0.20 mgkg-1）。养分添加处理和对照之间差异显著（p0.05）。表层0-10 cm土壤中，对照土壤速效磷含量最高在2012年6月（5.71 mgkg-1），最低在2011年12月（0.46 mgkg-1）；氮添加分别在2011年9月（2.82 mgkg-1）、2011年12月（1.41 mgkg-1）；氮磷添加分别在2011年12月（3.81 mgkg-1）、2011年12月（0.37 mgkg-1）。10-20 cm土层中对照土壤速效磷含量最高在2011年5月份（1.13 mgkg-1），最低在12月（0.58 mgkg-1）；氮添加分别出现在2012年4月（3.96 mgkg-1）和2011年7月（1.08 mgkg-1）；氮磷添加分别在2012年4月（3.34 mgkg-1）和2011年7月（0.92 mgkg-1）。对照和氮添加之间差异不显著（p0.05），氮磷添加和对照及氮添加之间差异显著（p 0.05).After the nutrient additions, the concentrations of NH4+-N in 0-10 cm soil layer were highest in June 2012 (11.05 mgkg-1) and lowest in December 2011 (3.60 mgkg-1) for the control (CK); whili highest in October 2011 (14.64 mgkg-1) and lowest in September 2011 (4.90 mgkg-1) for the nitrogen (N) addition, and highest in August 2011 (17.24 mgkg-1) and lowest in September 2011 (4.90 mgkg-1) for nitrogen and phosphorus (N+P) addition. In the 10-20cm soil layer, the NH4+-N concentrations were highest in August 2011 (19.16 mgkg-1) and lowest in the December 2011 (2.50 mgkg-1) for CK; but highest in August 2011 (11.67 mgkg-1) and lowest in July 2011 (3.41 mgkg-1) for N addition; and highest in August 2011 (15.45 mgkg-1) and lowest in July 2011 (2.97 mgkg-1) for N+P addition.Concentrations of NO3-N in 0-10 cm soil layer were highest in February 2012 (1.65 mgkg-1) and lowest in the December 2011 (0.17 mgkg-1) for CK; while highest in October of 2011 (22.51 mgkg-1) and lowest in April 2012 (0.17 mgkg-1) for N addition; and highest in October of 2011 (7.14 mgkg-1) and lowest in April 2012, 0.18 mgkg-1) for N+P addition. In the 10-20cm soil layer, the NO3-N concentrations were highest in July 2011 (1.43 mgkg-1) and lowest in October of 2011 (0.35 mgkg-1) for CK, highest in October of 2011 (10.08 mgkg-1) and lowest in April 2012 (0.18 mgkg-1) for N addition; while highest in October of 2011 (4.11 mgkg-1) and lowest in April 2012, 0.20 mgkg-1) for N+P addition. Significant differences were appeared between treatments and control (p 0.05).Concentrations of available P (AP) in 0-10 cm soil layer were highest in June 2012 (5.71 mgkg-1) and lowest in the December 2011 (0.46 mgkg-1) for CK; highest in September 2011 (2.82 mgkg-1) and lowest in the December 2011 (1.41 mgkg-1) for N addition; highest in December 2011 (3.81 mgkg-1) and lowest in the December 2011 (0.37 mgkg-1) for N+P addition. In 10-20cm soil layer, AP concentrations were highest in May (1.13 mgkg-1) and lowest in the December 2011 (0.58 mgkg-1) for CK; highest (3.96 mgkg-1) in April 2012 and lowest in July 2011 (1.08 mgkg-1) for N addition; highest levels in April 2012 (3.34 mgkg-1) and lowest in July 2011 (0.92 mgkg-1) for N+P addition. No significant difference appeared between CK and N addition (p 0.05), while significant differences appeared between CK and N+P addition addition (p 0.05).The contents of dissolved organic carbon (DOC) in 0-10 cm soil layer were highest in August 2011 (368.24 mg kg-1), lowest in October of 2011 (118.37 mgkg-1) for CK; and highest in August 2011 (391.16 mgkg-1) and lowest in June 2012 (84.32 mgkg-1) for N addition; while highest in August 2011 (381.43 mgkg-1) and lowest in June 2012 (92.71 mgkg-1) for N+P addition.The results from the in-situ incubation experiment showed that the rate of ammonification (Rna) in 0-10 cm soil layer was highest (556.87 gkg-1d-1) from June to July 2012 and lowest (-230.82 gkg-1d-1) from August to September 2011; for nitrification rate (Rnn) were 671.50 gkg-1d-1 from June to July 2012 and -18.67 gkg-1d-1 from February to April 2012; for mineralization rate (Rnm) were 1228.37 gkg-1d-11 from June to July 2012 and -163.31 gkg-1d-1 from August to September 2011. And in 10-20 cm soil layer, the highest Rna was 244.31 gkg-1d-1 from February to April 2012 and the lowest -467.57 gkg-1d-1 from August to September 2011; the highest Rnn was 201.13 gkg-1d-1 from June to July 2012 and the lowest -8.30 gkg-1d-1 from February to April 2012 ;the highest Rnm was 392.73 gkg-1d-1 from June to July 2012 and the lowest -438.28 from August to September 2011.In the treatment of N addition, the Rna in 0-10 cm soil layer was highest (583.64 gkg-1d-1) from June to July 2012 and lowest (-233.79 gkg-1d-1) from August to September 2011; for Rnn were 687.39 gkg-1d-1 from June to July 2012 ) and -343.87 gkg-1d-1 from October to December 2011; for Rnm were 1271.03 gkg-1d-11 from June to July 2012 and -278.10 gkg-1d-1 from October to December 2011. And in 10-20 cm soil layer, the highest Rna was 285.31 gkg-1d-1 from June to July 2012 and the lowest -264.72 gkg-1d-1 from August to September 2011; the highest Rnn was 177.65 gkg-1d-1 from June to July 2012 and the lowest -89.26 gkg-1d-1 from October to December 2011; the highest Rnm was 462.97 gkg-1d-1 from June to July 2012 and the lowest -190.86 from October to December 2011.In the treatment of N+P addition, the Rna in 0-10 cm soil layer was highest (379.83 gkg-1d-1) from September to October 2011 and lowest (-404.18 gkg-1d-1) from August to September 2011; for Rnn were 676.65 gkg-1d-1 from June to July 2012 and -64.36 gkg-1d-1 from October to December 2011; for Rnm were 877.39 gkg-1d-1 from June to July 2012 and -407.86 gkg-1d-1 from August to September 2011. And in 10-20 cm soil layer, the highest Rna was 162.31 gkg-1d-1 from June to July 2012 and the lowest -417.96 gkg-1d-1 from August to September 2011; the highest Rnn was 285.00 gkg-1d-1 from September to October 2011 and the lowest -417.96 gkg-1d-1 from August to September 2011; the highest Rnm was 351.21 gkg-1d-1 from June to July 2012 and the lowest -425.14 gkg-1d-1 from August to September 2011.The results show that the inorganic nitrogen concentrations in the surface soil layer one month after the treatments were higher than than for the control, with more sensitive to nutrient additions in 0-10 cm soil layer than in 10-20 cm soil layer. This indicates that short-term (1-2 years) N addition can significantly affect soil N mineralization, particularly for the surface soil. The N and N+P additions made a significant increase in concentrations of NH4+-N and NO3-N in the two soil layers, while no significant difference occurred between the two treatments. The AP concentration is higher for the treatments than for the control. The differences became greater as fertilization continued. However, no significant difference occurred for AP between N addition and control.The rates of ammonification, nitrification and mineralization in 0-10 cm and 10-20 cm soil layers showed a similar seasonal pattern despite the different treatments. The annual mean nitrogen transformation rate is highest in summer and lowest in winter. The preliminary results of this study showed that the annual average mineralization rate was dropped by nutrient additions. The N addition resulted in decline of nitrification rate and increase of ammonification rate. However, N+P addition caused to increase nitrification rate and to decrease ammonification rate. The effects of nutrient addition on N dynamics in forest ecosystem need long-term observation. Keywords：forest soil, nitrogen dynamics, nitrogen transformation, nutrient addition, nutrient availability, subtropical forest 目 录摘 要IAbstractIII插图和附表清单X1 文献综述11.1氮沉降的国内外研究动态1 1.1.2 国内外氮沉降的现状1 1.1.3 国内外对大气氮沉降的研究进展11.2土壤氮素矿化的国内外研究动态41.2.1土壤氮素矿化的研究方法41.2.2 影响土壤氮素矿化的因素51.2.3施肥对土壤氮素矿化的影响61.3土壤氮磷化学计量研究进展72研究目的与意义93研究方法103.1实验地概况及试验材料103.1.1实验地概况103.2技术路线113.3研究方法123.3.1样地设计和处理123.3.2样品的采集与处理123.3.3化学分析123.3.4数据处理133.3.5数据分析134结果与分析144.1安徽查湾亚热带常绿阔叶林环境因子144.1.1气温和降雨量季节动态144.1.2土壤含水量季节动态144.2立地土壤化学特性154.3养分添加对安徽查湾亚热带常绿阔叶林土壤有效氮的影响174.3.1养分添加对土壤铵态氮的影响184.3.2养分添加对土壤硝态氮的影响184.3.3养分添加对土壤有效氮的影响194.3.4土壤有效氮影响因子分析224.4 养分添加对安徽查湾亚热带常绿阔叶林土壤有效氮氮素矿化的影响234.4.1养分添加对土壤净铵化速率的影响234.4.2养分添加对土壤净硝化速率的影响244.4.3养分添加对土壤氮素净矿化的影响254.4.4土壤氮素矿化速率影响因子分析264.4.5养分添加对土壤氮素年平均转化速率的影响274.5养分添加对土壤有效磷的影响284.5.1土壤有效磷含量284.5.2土壤有效磷和有效氮的相关性分析314.5.3土壤有效氮和有效磷的比例关系314.6养分添加对土壤可溶性有机碳的影响324.6.1土壤可溶性有机碳含量324.6.2土壤可溶性有机碳和有效氮的相关性分析334.6.3土壤可溶性有机碳和有效氮的比例关系345 结论与讨论365.1养分添加对土壤养分的影响365.1.1 土壤有效氮365.1.2 土壤有效磷365.1.3 土壤可溶性有机碳375.2土壤氮素矿化特征385.2.1土壤N/P比和净矿化速率的关系385.2.2土壤DOC/AN比和净矿化速率的关系405.3小结42参考文献43致谢53作者简介54在读期间发表的论文54插图和附表清单表4-1 安徽查湾自然保护区常绿阔叶林土壤基本理化性质16Table 4-1 Soil physicochemical properties of subtropical evergreen broad-leaved forest in Chawan Natural Reserve, Anhui表4-2 不同处理土壤的化学性状相关分析表17Table 4-2 Correlations of some physicochemical properties of surface soils under the different nutrient additions表4-3 土壤有效氮影响因素方差分析23Table 4-3 Results of the ANOVA for soil available nitrgen表4-4 土壤氮素矿化速率影响因素方差分析27Table 4-4 Results of the ANOVA for soil nitrgen transformation rate表4-5 养分添加对土壤氮素年平均转化速率的影响28Table 4-5 Annual mean rates of soil nitrogen transformation under the different nutrient additions表4-6 土壤有效磷和有效氮的方差分析30Table 4-6 Results of the ANOVA for soil available P and N表4-7 土壤DOC和有效氮的方差分析33Table 4-7 Results of the ANOVA for soil DOC and available N图3-1试验研究技术路线图.11Fig.3-1 Technical route of this study图4-1安徽查湾自然保护区试验地气温及年降雨量14Fig. 4-1 Air temperature and annual rainfall in the experimental forest in Chawan Natural Reserve, Anhui图4-2土壤0-10 cm和10-20 cm土层含水量动态变化15Fig. 4-2 Monthly changes in soil moisture for two soil depths (0-10 cm and 10- 20 cm ) under the different nutrient additions图4-3 土壤0-10 cm和10-20 cm土层铵态氮含量变化18Fig. 4-3 Monthly changes in extractable NH4+-N for two soil depths (0-10 cm and 10- 20 cm ) under different nutrients additions图4-4 土壤0-10 cm和10-20 cm土层硝态氮含量变化19Fig. 4-4 Monthly changes in extractable N03-N for two soil depths (0-10 cm and 10- 20 cm ) under the different nutrient additions图4-5 土壤0-10 cm和10-20 cm土层有效氮含量变化21Fig. 4-5 Monthly changes in available N for two soil depths (0-10 cm and 10- 20 cm ) under the different nutrient additions图4-6 土壤0-10 cm土层和10-20 cm土层铵态氮占总有效氮比例的变化21Fig. 4-6 Monthly changes in the percentage of NH4+-N to total available nitrogen for two soil depths (0-10 cm and 10- 20 cm ) under the different nutrient additions图4-7 不同处理土壤净铵化速率24Fig. 4-7 Temporal patterns of net ammonification rate under the different nutrient additions图4-8 不同处理土壤净硝化速率25Fig. 4-8 Temporal patterns of net nitrification rate under the different nutrient additions图4-9 不同处理土壤净矿化化速率26Fig. 4-9 Temporal patterns of net mineralization rate under the different nutrient additions图4-10 土壤0-10 cm和10-20 cm土层有效磷含量变化29Fig. 4-10 Monthly changes in available P for two soil depths (0-10 cm and 10- 20 cm ) under the different nutrient additions图4-11 土壤0-10 cm和10-20 cm土层有效磷和有效氮的相关性30Fig. 4-11 Relationship between available P and N for two soil depths (0-10 cm and 10- 20 cm ) under the different nutrient additions图4-12 土壤0-10 cm和10-20 cm土层有效氮和有效磷比值变化31Fig. 4-12 Monthly changes in N/P ratios for two soil depths (0-10 cm and 10- 20 cm ) under the different nutrient additions图4-13 土壤0-10 cm和10-20 cm土层DOC含量变化32Fig. 4-13 Monthly changes of DOC for two soil depths (0-10 cm and 10- 20 cm ) under the different nutrient addition