|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | 人工模拟降水条件下旱作农田土壤“Birch效应”及其响应机制显示文摘降水事件引起干土复湿刺激土壤CO_2,脉冲释放的现象被称为'Birch效应',其作用机制可能是降水刺激土壤'底物供给'增加或引起土壤'微生物胁迫'所致。为深入了解土壤'Birch效应'对降水格局改变的响应过程及内在机制,在冬小麦拔节期和夏闲期分别进行了不同降水量(1-32 mm)人工模拟降水实验,系统观测了降水后0-72 h土壤呼吸及土壤碳组分变化特征,结果表明:土壤呼吸随降水量的增大而增强,1-16 mm降水土壤呼吸峰值出现在降水后4h,而32 mm降水土壤呼吸峰值出现时间滞后了4 h。与较小降水量相比,较大的降水量能增加土壤呼吸但会推迟土壤呼吸峰值出现时间。土壤呼吸速率峰值(SRP)与降水量(P)呈幂相关(拔节期:SR-P=0.97P^(0.09),R^2=0.5,P<0.05;夏闲期:SR-P=1.07P^(0.09),R^2=0.98,P<0.01)。降水后72h累积CO_2释放量(CO_2-P)与降水量呈线性相关(拔节期:CO_2-P=0.03P+5.99,R^2=0.58,P<0.05;夏闲期:CO_2-P=0.11P+6.04,R^2=0.86,P<0.01)。土壤呼吸温度敏感性系数和降水量之间存在二次曲线关系(拔节期:Q_(10)=-0.007P^2+0.2P+0.7,R^2=0.32,R^2<0.05;夏闲期:Q_(10)=-0.01P^2+0.3P+0.2,R^2=0.86,P<0.01)。逐步回归分析表明,冬小麦拔节期所有降水量处理土壤呼吸与土壤微生物量碳相关性均达到显著水平(P<0.05),指示土壤'Birch效应'是由'微生物胁迫'所致。而在夏闲期,当降水量小于8 mm时土壤呼吸与微生物量碳相关性显著,即以微生物胁迫机制占主导;8 mm降水处理下土壤呼吸与氯仿熏蒸-K_2SO_4提取态有机碳相关性达到极显著水平,指示则为两种机制共同起作用,而当降水量大于16 mm时,土壤呼吸主要与可提取态有机碳显著相关,'Birch'效应转为以底物供给机制占主导。与夏闲期相比,冬小麦拔节期作物生长会削弱'Birch效应',并改变其响应机制。 | 陈荣荣 刘全全 王俊 刘文兆 Upendra M. Sainju | 2016 | 生态学报2016，36，2： | 18 |
| 2 | Tillage, crop residue, and nutrient management effects on.soil organic carbon in rice-based cropping systems: A review显示文摘Soil organic carbon(SOC) sequestration is one of the major agricultural strategies to mitigate greenhouse gas(GHG)emissions,enhance food security,and improve agricultural sustainability.This paper synthesizes the much-needed stateof-knowledge on the effects of tillage,crop residue,and nutrient management practices on SOC sequestration and identifies potential research gap,opportunities,and challenges in studying SOC dynamics in rice(Oryza sativa L.)-based cropping systems in South Asia,mainly in Bangladesh,Bhutan,India,Nepal,Pakistan,and Sri Lanka.Improved management practices such as reduced- and no-tillage management,nitrogen(N) fertilizer and farmyard manure(FYM) application,and crop residue addition can improve SOC accumulation.Positive effects of no-tillage,crop residue addition,N addition through manure or compost application,and integration of organic and chemical fertilizers on SOC accumulation in rice-based cropping systems have been documented from South Asia.However,limited data and enormous discrepancies in SOC measurements across the region exist as the greatest challenge in increasing SOC sequestration and improving agricultural sustainability.More research on SOC as influenced by alternative tillage,crop residue,and nutrient management systems,and development of SOC monitoring system for existing long-term experiments will advance our understanding of the SOC dynamics in rice-based cropping systems and improve agricultural system sustainability in South Asia. | Rajan Ghimire Sushil Lamichhane Bharat Sharma Acharya Prakriti Bista Upendra Man Sainju | 2017 | Journal of Integrative Agriculture2017，16，1： | 11 |
| 3 | Soil Carbon and Nitrogen in Response to Perennial Bioenergy Grass, Cover Crop and Nitrogen Fertilization显示文摘Cover crop and nitrogen(N) fertilization may maintain soil organic matter under bioenergy perennial grass where removal of aboveground biomass for feedstock to produce cellulosic ethanol can reduce soil quality. We evaluated the effects of cover crops and N fertilization rates on soil organic carbon(C)(SOC), total N(STN), ammonium N(NH_4-N), and nitrate N(NO_3-N) contents at the0–5, 5–15, and 15–30 cm depths under perennial bioenergy grass from 2010 to 2014 in the southeastern USA. Treatments included unbalanced combinations of perennial bioenergy grass, energy cane(Saccharum spontaneum L.) or elephant grass(Pennisetum purpureum Schumach.), cover crop, crimson clover(Trifolium incarnatum L.), and N fertilization rates(0, 100, and 200 kg N ha^(-1)). Cover crop biomass and C and N contents were greater in the treatment of energy cane with cover crop and 100 kg N ha^(-1) than in the treatment of energy cane and elephant grass. The SOC and STN contents at 0–5 and 5–15 cm were 9%–20% greater in the treatments of elephant grass with cover crop and with or without 100 kg N ha^(-1)than in most of the other treatments. The soil NO_3-N content at 0–5 cm was 31%–45% greater in the treatment of energy cane with cover crop and 100 kg N ha^(-1)than in most of the other treatments.The SOC sequestration increased from 0.1 to 1.0 Mg C ha^(-1)year^(-1)and the STN sequestration from 0.03 to 0.11 Mg N ha^(-1)year^(-1)from 2010 to 2014 for various treatments and depths. In contrast, the soil NH_4-N and NO_3-N contents varied among treatments,depths, and years. Soil C and N storages can be enriched and residual NO_3-N content can be reduced by using elephant grass with cover crop and with or without N fertilization at a moderate rate. | Upendra M. SAINJU Hari P. SINGH Bharat P. SINGH | 2017 | Pedosphere2017，27，2： | 2 |
| 4 | Tillage, cropping systems, and nitrogen fertilizer source effects on soil car- bon sequestration and fractions 显示文摘 | Sainju U M Senwo Z N Nyakatawa E Z | 2008 | Journal of Environment Quality2008，37，： | 1 |
| 5 | Plant biomass and soil carbon and nitrogen fractions on transient land as influenced by tillage and crop rotation显示文摘 | SAINJU U M LENSSEN A CAESAR-THONTHAT T | 2007 | Soil & Tillage Research2007，93，： | 1 |
| 6 | Cover crops and nitrogen fertilization effects on soil carbon and nitrogen and tomato yield 显示文摘 | Sainju U M Singh B P Whitehead W F | 2000 | Canadian Journal of Soil Science2000，180，3： | 1 |
| 7 | microbiology of dacryocystitis among adults population in southern Auatralia 显示文摘 | Sainju R Franzco AA Shrestha MK et a l | 2005 | Nepal Med Coll J2005，7，1： | 1 |
| 8 | Vertical root distribution in relation to soil properties in New Jersy Pineland forests 显示文摘 | Sainju U M Good D E | 1993 | Plant and Soil1993，150，1： | 1 |
| 9 | Microbiology of dacryucystitis among adults population in southern Australia显示文摘 | Sainju R Franzeo A A Shrestha MK | 2005 | Nepal Med Coil J2005，7，： | 1 |
| 10 | Soil aggregation and carbon and nitrogen pools under rhizoma peanut and perennial weeds显示文摘 | Sainju U M Terrill T H Gelaye S | 2003 | Soil Science Society of America Journal2003，67，： | 1 |
| 11 | Long term effects of tillage, cover crops, and nitrogen fertilization on organic carbon and nitrogen concentration in sandy loam soils in Georgia显示文摘 | Sainju UM Singh BP Hitehead W | 2002 | Soil and Tillage Research2002，63，34： | 1 |
| 12 | Dryland crop yields and soil organic matter as influenced by long-term tillage and cropping sequence显示文摘 | SAINJU U M LENSSEN A W CAESAR-TON THAT T | | 0，，02： | 1 |
| 13 | Carbon and nitrogen pools in soil aggregates ~eparated by dry and wet sieving methods显示文摘 | Sainju Upendra M | 2006 | Soil Science2006，171，12： | 1 |
| 14 | Dryland plant biomass and soil carbon and nitrogen fractions on transient land as in- fluenced by tillage and crop rotation显示文摘 | Sainju U M Lenssen A Caesar-Thonthat T | 2007 | Soil & Tillage Research2007，93，2： | 1 |
| 15 | Carbon dioxide flux as affected by tillage and irrigation in soil converted from perennial forages to annual crops显示文摘 | Jabro J D Sainju U Stevens W B | 2008 | Journal of Environmental Management2008，88，： | 1 |
| 16 | A multi-objective geographic information system for route selection of nuclear waste transport显示文摘 | Chen Yuhwen Wang Chihwang Lin Sainju | 2008 | The International Journal of Management Science2008，36，3： | 1 |
| 17 | Soil Carbon Dioxide Emission and Carbon Content as Affected by Irrigation, Tillage, Cropping System, and Nitrogen Fertilization显示文摘 | Sainju Upendra M Jabro Jalal D Stevens William B | 2008 | Journal of Environmental Quality2008，，1： | 1 |
| 18 | Winter cover crop effects on soil organic carbon and carbohydrate in soil显示文摘 | KUO S SAINJU U M JELLUM E J | 1997 | Soil Sci Soc Am J1997，61，： | 1 |
| 19 | Carbon dioxide flux as effected by tillage and irrigation in soil converted from perennial forages to annual crops 显示文摘 | Jabro J D Sainju U Stevens W B | 2008 | Journal of Environmental Management2008，88，4： | 1 |
| 20 | Carbon and nitrogen pools in soil aggregates separated by dry and wet sieving methods显示文摘 | Sainju U M | 2006 | Soil Science2006，171，12： | 1 |
您所在的机构暂未开通此部分的功能，请联系管理员