Located in an earthquake-prone region,the geological structures in Yunnan Province are complex. Taking into account that Tonghai county is located in the intersection of Xiaojiang fault and Honghe fault, an ACF-4M ELF...Located in an earthquake-prone region,the geological structures in Yunnan Province are complex. Taking into account that Tonghai county is located in the intersection of Xiaojiang fault and Honghe fault, an ACF-4M ELF electromagnetic instrument was installed at the Tonghai seismic station,which has produced continuous reliable data. The author collected the data and information for the year 2009 and 2010,and performed analysis on the variation characteristics of both geomagnetic fields and electrical resistivity. The result shows that the 1Hz and 39Hz electromagnetic power spectra are 0. 2 to 1. 4 orders of magnitude higher than the normal values immediately before many earthquakes. The anomalies are represented by the abrupt changes of the electric and magnetic field power spectra in earthquake and aftershock sequences,and the amplitude of change is related to the size of earthquake magnitude and epicentral distance. The electrical resistivity also obviously changes. Therefore, further research on the anomalous characteristics of ELF electromagnetic data will be meaningful to the future use of this instrument in earthquake prediction.展开更多
With the continuous emergence of global development problems,the dynamic conservation and sustainable development of Important Agricultural Heritage Systems(IAHS)have been assigned greater importance.However,due to th...With the continuous emergence of global development problems,the dynamic conservation and sustainable development of Important Agricultural Heritage Systems(IAHS)have been assigned greater importance.However,due to the complex structure,multi-component,dynamic,and open characteristics of IAHS,there are neglected problems which need to be solved in conservation practice,such as component element ambiguity,obscurity of the conservation redline,etc.This study defined the concept of key elements(KE)of IAHS,put forward a conceptual framework of KE identification,conducted empirical research by taking Honghe County of Honghe Hani Rice Terraces System(HHRTS)as an example and analyzed the level of recognition motivations for different stakeholder groups.The following conclusions were drawn:1)The KE of HHRTS are grain crops,rice species biodiversity,terrace construction and maintenance technique,Hani traditional festivals,Hani traditional foods,and virgin forest;2)The reasons behind the KE priorities of farmers,businessmen and tourists were at the micro level,the reasons of officers were at the middle level and the reasons of researchers were at the macro level.The empirical study conducted in HHRTS showed that the proposed conceptual framework could identify KE of IAHS effectively,and provided a theoretical perspective for the structuring of and essential need for IAHS research.Moreover,the KE recognition levels of different stakeholder groups reflected their potential action strategies.We should focus on the coherence of policies and measures in both the microscale and macroscale to balance the diversified demands of stakeholders,and to stimulate their enthusiasm for participation in the conservation in order to improve the management level of IAHS sites.展开更多
基金funded by Seismic Monitoring,Prediction and Research Project"The Application of Ultra Low Frequency Electromagnetic Observation in Yunnan and Its Adjacent Region"of China Earthquake Administration in 2010
文摘Located in an earthquake-prone region,the geological structures in Yunnan Province are complex. Taking into account that Tonghai county is located in the intersection of Xiaojiang fault and Honghe fault, an ACF-4M ELF electromagnetic instrument was installed at the Tonghai seismic station,which has produced continuous reliable data. The author collected the data and information for the year 2009 and 2010,and performed analysis on the variation characteristics of both geomagnetic fields and electrical resistivity. The result shows that the 1Hz and 39Hz electromagnetic power spectra are 0. 2 to 1. 4 orders of magnitude higher than the normal values immediately before many earthquakes. The anomalies are represented by the abrupt changes of the electric and magnetic field power spectra in earthquake and aftershock sequences,and the amplitude of change is related to the size of earthquake magnitude and epicentral distance. The electrical resistivity also obviously changes. Therefore, further research on the anomalous characteristics of ELF electromagnetic data will be meaningful to the future use of this instrument in earthquake prediction.
基金Strategic Priority Research Program of the Chinese Academy of Sciences (XDA23100203)。
文摘With the continuous emergence of global development problems,the dynamic conservation and sustainable development of Important Agricultural Heritage Systems(IAHS)have been assigned greater importance.However,due to the complex structure,multi-component,dynamic,and open characteristics of IAHS,there are neglected problems which need to be solved in conservation practice,such as component element ambiguity,obscurity of the conservation redline,etc.This study defined the concept of key elements(KE)of IAHS,put forward a conceptual framework of KE identification,conducted empirical research by taking Honghe County of Honghe Hani Rice Terraces System(HHRTS)as an example and analyzed the level of recognition motivations for different stakeholder groups.The following conclusions were drawn:1)The KE of HHRTS are grain crops,rice species biodiversity,terrace construction and maintenance technique,Hani traditional festivals,Hani traditional foods,and virgin forest;2)The reasons behind the KE priorities of farmers,businessmen and tourists were at the micro level,the reasons of officers were at the middle level and the reasons of researchers were at the macro level.The empirical study conducted in HHRTS showed that the proposed conceptual framework could identify KE of IAHS effectively,and provided a theoretical perspective for the structuring of and essential need for IAHS research.Moreover,the KE recognition levels of different stakeholder groups reflected their potential action strategies.We should focus on the coherence of policies and measures in both the microscale and macroscale to balance the diversified demands of stakeholders,and to stimulate their enthusiasm for participation in the conservation in order to improve the management level of IAHS sites.