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西北农林科技大学学报(自然科学版) 1985年第3期 1-10页

作者：杨天章 S. S. Maan 西北农学院农学系美国北达科他州立大学农学系教授博士

利用恢复系 R113同10种不同细胞质的异质小麦雄性不育系 Selkirk（或 chris）进行了杂交,以鉴定 R113对这些雄性不育系的恢复力。其中有7种细胞质的雄性不育性在不同程度上为 R113所恢复,证明了 R113恢复性的广泛性。特别值得注意的是 R... 详细信息

利用恢复系 R113同10种不同细胞质的异质小麦雄性不育系 Selkirk（或 chris）进行了杂交,以鉴定 R113对这些雄性不育系的恢复力。其中有7种细胞质的雄性不育性在不同程度上为 R113所恢复,证明了 R113恢复性的广泛性。特别值得注意的是 R113对***细胞质不育的恢复度极高（118.6%—根据穗粒数除以两侧小花数计算）。其恢复性可能由两对恢复基因控制。根据杂交种与其亲本之间以及同质 Selkirk 与异质 Sel-kirk 品种之间的比较,大多数所测性状（如株高、抗倒伏、每穗小穗数,每穗粒数每穗粒重等）在 *** 细胞质背景下都有明显的优势。试验证明,在小麦中确实存在着两种杂种优势:即核间杂种优势和核质间杂种优势。*** 细胞质的缺点是较晚熟,然而,延长春化时间可以提早抽穗;同时在其同早熟亲本杂交的后代中,可以选出早熟植株。本试验的意义在于:①证实了核质杂种优势的存在;②*** 细胞质具有明显的核质杂种优势;③发现了恢复系 R113可以完全恢复 *** 细胞质的雄性不育性,④*** 细胞质的晚熟性可以改良。因此,在小麦常规育种中或在杂种优势利用上,可以应用 *** 细胞质研究把上述两种杂种优势结合起来,选育优良小麦核质杂种品种或杂种小麦的可能性。特别是在冬麦区,自然春化就可部分克服 *** 细胞质的晚熟缺点。

关键词：细胞质杂种优势胞浆杂交优势麦类作物小麦 Ae.ovata 育性核质杂种每穗粒数春化处理优势研究

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Land use induced changes of organic carbon storage in soils of China

Land use induced changes of organic carbon storage in soils ...

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中国科学院地质与地球物理研究所2003学术年会

作者： HAIBIN WU~*,ZHENGTANG GUO~(1+*) and CHANGHUI PENG~(++) *Institute of Earth Environment,1State Key Laboratory of Loess and Quaternary Geology,Chinese Academy of Sciences,Xi’an 710075,China,+Institute of Geology and Geophysics,Chinese Academy of Sciences,PO Box 9825,Beijing 100029,China,++Institute of Atmospheric Sciences,South dakota School of Mines and Technology 501 E.St Joseph,Rapid City,SD 57701-3995,USA

Using the data compiled from China’s second national soil survey and an improved method of soil carbon bulk density,we have estimated the changes of soil organic carbon due to land use,and compared the spatial distribution and storage of soil organic carbon (SOC) in cultivated soils and noncultivated soils in *** results reveal that～57% of the cultivated soil subgroups(～31%of the total soil surface) have experienced a significant carbon loss,ranging from 40%to 10%relative to their noncultivated counterparts. The most significant carbon loss is observed for the non-irrigated soils(dry farmland) within a semiarid/semihumid belt from northeastern to southwestern China, with the maximum loss occurring in northeast *** the contrary,SOC has increased in the paddy and irrigated soils in northwest *** significant change is observed for forest soils in southern China,grassland and desert soils in northwest China,as well as irrigated soils in eastern *** SOC storage and density under noncultivated conditions in China are estimated to～77.4Pg(10g) and～8.8 kg Cm,respectively, compared to a SOC storage of～70.3 Pg and an average SOC density of～8.0 kg Cm under the present-day *** suggests a loss of～7.1 Pg SOC and a decrease of -0.8 kg Cm SOC density due to increasing human activities,in which the loss in organic horizons has contributed to～77%.This total loss of SOC in China induced by land use represents～9.5%of the world’s SOC *** amount is equivalent to～3.5 ppmv of the atmospheric CO ***～78%of the currently cultivated soils in China have been degraded to a low/medium productivities and are responsible for most of the SOC loss,an improved land management,such as the development of irrigated and paddy land uses,would have a considerable potential in restoring the SOC *** a restoration of～50%of the lost SOC during the next 20-50 years,the soils in China would absorb～3.5 Pg of carbon from the atmosphere.

关键词： carbon density carbon pool human activities soil organic carbon loss

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Estimating the spatial distribution of organic carbon density for the soils of Ohio, USA

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Journal of Geographical Sciences 2013年第2期23卷 280-296页

作者： Sandeep KUMAR Rattan LAL Desheng LIU Rashid RAFIQ DepartmentofPlantScience.Room248CNPB BOX2140C1110RotundaLaneNorthSouthDakotaStateUniversityBrookingsSD57007USA CarbonManagementandSequestrationCenter SchoolofEnvironmentandNaturalResourcesTheOhioStateUniversity2021CoffeyRoad414AKo~manHallColumbusOH43210-1085USA DepartmentofGeographyandDepartmentofStatistics TheOhioStateUniversityColumbusOH43210USA DepartmentofMicrobiology&PlantBiology.UniversityofOklahoma NormanOK73019USA

Historical database of National Soil Survey Center containing 1424 geo-referenced soil profiles was used in this study for estimating the organic carbon （SOC） for the soils of Ohio, USA. Specific objective of the study was to estimate the spatial distribution of SOC density （C stock per unit area） to 1.0-m depth for soils of Ohio using geographically weighted regression （GWR）, and compare the results with that obtained from multiple linear regression （MLR）. About 80% of the analytical data were used for calibration and 20% for validation. A total of 20 variables including terrain attributes, climate data, bedrock geology, and land use data were used for mapping the SOC density. Results showed that the GWR provided better estimations with the lowest （3.81 kg m-2） root mean square error （RMSE） than MLR approach Total estimated SOC pool for soils in Ohio ranged from 727 to 742 Tg. This study demon strates that, the local spatial statistical technique, the GWR can perform better in capturing the spatial distribution of SOC across the study region as compared to other global spatial statistical techniques such as MLR. Thus, GWR enhances the accuracy for mapping SOC density.

关键词： geographically weighted regression multiple linear regression major land resource areas root meansquare error soil organic carbon

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