为了解膜下滴灌土壤硝化、反硝化作用的变化规律,应用气压过程分离(Barometric process separation,BaPS)方法,研究了施氮肥、有机肥与氮肥配施和不施肥3种不同施肥处理的土壤硝化、反硝化速率在覆膜与裸地条件下的动态变化。结果显示,...为了解膜下滴灌土壤硝化、反硝化作用的变化规律,应用气压过程分离(Barometric process separation,BaPS)方法,研究了施氮肥、有机肥与氮肥配施和不施肥3种不同施肥处理的土壤硝化、反硝化速率在覆膜与裸地条件下的动态变化。结果显示,不同处理下土壤硝化、反硝化作用随着玉米生育期的推移有明显的变化。相同栽培措施不同施肥处理间土壤硝化、反硝化速率差异均达极显著水平,且大小顺序为氮+有机肥配施处理>施氮肥处理>不施肥处理(对照);相同施肥处理不同栽培措施间土壤硝化、反硝化速率大小顺序均为覆膜处理>裸地处理。展开更多
A facility of BaPS （Barometric Process Separation） was used to determine soil respiration, gross nitrification and denitrification in a winter wheat field with depths of 0-7, 7--14 and 14-21 cm. N2O production was d...A facility of BaPS （Barometric Process Separation） was used to determine soil respiration, gross nitrification and denitrification in a winter wheat field with depths of 0-7, 7--14 and 14-21 cm. N2O production was determined by a gas chromatograph. Crop root mass and relevant soil parameters were measured. Results showed that soil respiration and gross nitrification decreased with the increase of soil depth, while denitrification did not change significantly. In comparison with no-plowing plot, soil respiration increased significantly in plowing plot, especially in the surface soil of 0-7 cm, while gross nitrification and denitrification rates were not affected by plowing. Cropping practice in previous season was found to affect soil gross nitrification in the following wheat-growing season. Higher gross nitrification rate occurred in the filed plot with preceding crop of rice compared with that of maize for all the three depths of 0-7, 7-14 and 14-21 cm. A further investigation indicated that the nitrification for all the cases accounted for about 76% of the total nitrogen transformation processes of nitrification and denitrification and the N2O production correlated with nitrification significantly, suggesting that nitrification is a key process of soil N2O production in the wheat field. In addition, the variations of soil respiration and gross nitrification were exponentially dependent on root mass （p〈0.00l）.展开更多
采用气压过程分离(Barometric process separation,BaPS)技术对川西亚高山针叶林不同恢复阶段土壤的总硝化和反硝化作用速率进行了测定,结果表明川西亚高山针叶林不同恢复阶段土壤的总硝化和反硝化速率差异不显著(p<0.05),不同恢复...采用气压过程分离(Barometric process separation,BaPS)技术对川西亚高山针叶林不同恢复阶段土壤的总硝化和反硝化作用速率进行了测定,结果表明川西亚高山针叶林不同恢复阶段土壤的总硝化和反硝化速率差异不显著(p<0.05),不同恢复阶段土壤总硝化作用的Q10值差异不显著(p<0.05);总硝化作用速率与土壤含水量呈显著正相关(p<0.05),与土壤pH值、土壤有机质、全氮及C/N相关不显著;不同恢复阶段土壤反硝化速率均维持在一个较低的水平,反硝化速率与土壤中的C/N显著正相关(p<0.05),与土壤含水量、pH值、有机质及全氮相关不显著。与反硝化作用相比,硝化作用对亚高山针叶林土壤氮损失的影响可能更大。展开更多
采用气压过程分离(Barometric process separation,BaPS)技术,研究油松(Pinus tabulaeformis Carr.)天然林土壤含水量、土壤温度和细根生物量对土壤总硝化速率、反硝化速率和呼吸速率的影响及其在0～52cm土层的变化.结果表明:油松天然...采用气压过程分离(Barometric process separation,BaPS)技术,研究油松(Pinus tabulaeformis Carr.)天然林土壤含水量、土壤温度和细根生物量对土壤总硝化速率、反硝化速率和呼吸速率的影响及其在0～52cm土层的变化.结果表明:油松天然林内土壤总硝化速率和呼吸速率随土层深度增加呈递减趋势,反硝化速率在各层间的波动较大;土壤总硝化速率和呼吸速率与土壤含水量、土壤温度及细根生物量均显著正相关(P<0.05);土壤反硝化速率和土壤含水量、土壤温度以及细根生物量相关不显著.展开更多
背景与目的肺癌易发生骨转移,I型胶原羧基端肽β特殊序列(β isomer of C-terminal telopeptide of type I collagen,β-CTX)和骨源性碱性磷酸酶(bone-specific alkaline phosphates,BAP)在骨质代谢中是重要的生化标记物,本研究旨在探...背景与目的肺癌易发生骨转移,I型胶原羧基端肽β特殊序列(β isomer of C-terminal telopeptide of type I collagen,β-CTX)和骨源性碱性磷酸酶(bone-specific alkaline phosphates,BAP)在骨质代谢中是重要的生化标记物,本研究旨在探讨骨代谢生化指标和肺癌骨转移进展程度的相关性,有助于早期判断是否有肺癌骨转移的发生。方法天津市人民医院2009年7月-2012年7月共收治92例肺癌并发生骨转移患者,全部病例其原发灶均经细胞学检查证实,骨转移灶的数目及类型经ECT结合X线片、CT证实,采用ELISA方法检测血β-CTX、BAP的浓度水平。结果收集的92例肺癌伴骨转移的患者中,转移灶<3处为58例,≥3处为34例;溶骨型68例,成骨型9例,混合型15例。血β-CTX、BAP水平在不同的骨转移数目组间差异有统计学意义(P<0.05),β-CTX在肺癌溶骨型骨转移患者中具有较高的敏感性。结论骨代谢生化指标β-CTX、BAP对肺癌骨转移具有辅助诊断意义,是判断转移进展程度的良好指标。展开更多
背景与目的骨代谢标志物是一类源于骨基质或骨细胞的代谢指标,可反映骨代谢情况。本研究旨在探讨血清骨代谢生化指标I型胶原交联羧基端肽(cross-linked telopeptide of type I collage,ICTP)和骨特异性碱性磷酸酶(bone-specific alkalin...背景与目的骨代谢标志物是一类源于骨基质或骨细胞的代谢指标,可反映骨代谢情况。本研究旨在探讨血清骨代谢生化指标I型胶原交联羧基端肽(cross-linked telopeptide of type I collage,ICTP)和骨特异性碱性磷酸酶(bone-specific alkaline phosphatase,BAP)在肺癌骨转移诊断中的意义及其临床应用价值。方法采用前瞻性对照方法,共入组110例,分为3组。初治肺癌患者共90例,临床分期为IV期,分为骨转移组50例和非骨转移组40例,健康对照组20例,采用酶联免疫法和电化学发光免疫测定法检测所有入组者治疗前的血清骨代谢生化指标ICTP和BAP水平,对骨转移的各因素与血清ICTP和BAP的相关性进行统计学分析。结果骨转移组的血清ICTP和BAP水平显著高于非骨转移组和健康对照组(P<0.05)。多发性骨转移组(骨转移数≥3)的血清BAP水平显著高于少发性骨转移组(骨转移数<3)(P<0.05)。混合性骨转移组的血清BAP水平显著高于溶骨性骨转移组(P<0.05)。ICTP和BAP在肺癌骨转移诊断中的敏感性分别为18%和40%,特异性分别为98.3%和95%,准确度分别为61.8%和70%。联合检测血清ICTP和BAP可提高其敏感性和准确度(分别为52%和74.5%)。结论由于检测方便、无创性、成本较低,血清骨代谢生化指标ICTP和BAP在肺癌骨转移的临床诊断中有一定的实用价值。展开更多
文摘为了解膜下滴灌土壤硝化、反硝化作用的变化规律,应用气压过程分离(Barometric process separation,BaPS)方法,研究了施氮肥、有机肥与氮肥配施和不施肥3种不同施肥处理的土壤硝化、反硝化速率在覆膜与裸地条件下的动态变化。结果显示,不同处理下土壤硝化、反硝化作用随着玉米生育期的推移有明显的变化。相同栽培措施不同施肥处理间土壤硝化、反硝化速率差异均达极显著水平,且大小顺序为氮+有机肥配施处理>施氮肥处理>不施肥处理(对照);相同施肥处理不同栽培措施间土壤硝化、反硝化速率大小顺序均为覆膜处理>裸地处理。
基金The Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX1-SW-01-13)
文摘A facility of BaPS （Barometric Process Separation） was used to determine soil respiration, gross nitrification and denitrification in a winter wheat field with depths of 0-7, 7--14 and 14-21 cm. N2O production was determined by a gas chromatograph. Crop root mass and relevant soil parameters were measured. Results showed that soil respiration and gross nitrification decreased with the increase of soil depth, while denitrification did not change significantly. In comparison with no-plowing plot, soil respiration increased significantly in plowing plot, especially in the surface soil of 0-7 cm, while gross nitrification and denitrification rates were not affected by plowing. Cropping practice in previous season was found to affect soil gross nitrification in the following wheat-growing season. Higher gross nitrification rate occurred in the filed plot with preceding crop of rice compared with that of maize for all the three depths of 0-7, 7-14 and 14-21 cm. A further investigation indicated that the nitrification for all the cases accounted for about 76% of the total nitrogen transformation processes of nitrification and denitrification and the N2O production correlated with nitrification significantly, suggesting that nitrification is a key process of soil N2O production in the wheat field. In addition, the variations of soil respiration and gross nitrification were exponentially dependent on root mass （p〈0.00l）.
文摘采用气压过程分离(Barometric process separation,BaPS)技术对川西亚高山针叶林不同恢复阶段土壤的总硝化和反硝化作用速率进行了测定,结果表明川西亚高山针叶林不同恢复阶段土壤的总硝化和反硝化速率差异不显著(p<0.05),不同恢复阶段土壤总硝化作用的Q10值差异不显著(p<0.05);总硝化作用速率与土壤含水量呈显著正相关(p<0.05),与土壤pH值、土壤有机质、全氮及C/N相关不显著;不同恢复阶段土壤反硝化速率均维持在一个较低的水平,反硝化速率与土壤中的C/N显著正相关(p<0.05),与土壤含水量、pH值、有机质及全氮相关不显著。与反硝化作用相比,硝化作用对亚高山针叶林土壤氮损失的影响可能更大。
文摘采用气压过程分离(Barometric process separation,BaPS)技术,研究油松(Pinus tabulaeformis Carr.)天然林土壤含水量、土壤温度和细根生物量对土壤总硝化速率、反硝化速率和呼吸速率的影响及其在0～52cm土层的变化.结果表明:油松天然林内土壤总硝化速率和呼吸速率随土层深度增加呈递减趋势,反硝化速率在各层间的波动较大;土壤总硝化速率和呼吸速率与土壤含水量、土壤温度及细根生物量均显著正相关(P<0.05);土壤反硝化速率和土壤含水量、土壤温度以及细根生物量相关不显著.
文摘背景与目的肺癌易发生骨转移,I型胶原羧基端肽β特殊序列(β isomer of C-terminal telopeptide of type I collagen,β-CTX)和骨源性碱性磷酸酶(bone-specific alkaline phosphates,BAP)在骨质代谢中是重要的生化标记物,本研究旨在探讨骨代谢生化指标和肺癌骨转移进展程度的相关性,有助于早期判断是否有肺癌骨转移的发生。方法天津市人民医院2009年7月-2012年7月共收治92例肺癌并发生骨转移患者,全部病例其原发灶均经细胞学检查证实,骨转移灶的数目及类型经ECT结合X线片、CT证实,采用ELISA方法检测血β-CTX、BAP的浓度水平。结果收集的92例肺癌伴骨转移的患者中,转移灶<3处为58例,≥3处为34例;溶骨型68例,成骨型9例,混合型15例。血β-CTX、BAP水平在不同的骨转移数目组间差异有统计学意义(P<0.05),β-CTX在肺癌溶骨型骨转移患者中具有较高的敏感性。结论骨代谢生化指标β-CTX、BAP对肺癌骨转移具有辅助诊断意义,是判断转移进展程度的良好指标。
文摘背景与目的骨代谢标志物是一类源于骨基质或骨细胞的代谢指标,可反映骨代谢情况。本研究旨在探讨血清骨代谢生化指标I型胶原交联羧基端肽(cross-linked telopeptide of type I collage,ICTP)和骨特异性碱性磷酸酶(bone-specific alkaline phosphatase,BAP)在肺癌骨转移诊断中的意义及其临床应用价值。方法采用前瞻性对照方法,共入组110例,分为3组。初治肺癌患者共90例,临床分期为IV期,分为骨转移组50例和非骨转移组40例,健康对照组20例,采用酶联免疫法和电化学发光免疫测定法检测所有入组者治疗前的血清骨代谢生化指标ICTP和BAP水平,对骨转移的各因素与血清ICTP和BAP的相关性进行统计学分析。结果骨转移组的血清ICTP和BAP水平显著高于非骨转移组和健康对照组(P<0.05)。多发性骨转移组(骨转移数≥3)的血清BAP水平显著高于少发性骨转移组(骨转移数<3)(P<0.05)。混合性骨转移组的血清BAP水平显著高于溶骨性骨转移组(P<0.05)。ICTP和BAP在肺癌骨转移诊断中的敏感性分别为18%和40%,特异性分别为98.3%和95%,准确度分别为61.8%和70%。联合检测血清ICTP和BAP可提高其敏感性和准确度(分别为52%和74.5%)。结论由于检测方便、无创性、成本较低,血清骨代谢生化指标ICTP和BAP在肺癌骨转移的临床诊断中有一定的实用价值。
