数字合作时代的到来,对学习者的数字素养要求也提高了。联合国教科文组织发布的《全球数字素养框架》(Digital Literacy Global Framework,简称DLGF)及其评估建议报告可用于指导开展数字素养的培育和评估工作。报告介绍了由框架映射、...数字合作时代的到来,对学习者的数字素养要求也提高了。联合国教科文组织发布的《全球数字素养框架》(Digital Literacy Global Framework,简称DLGF)及其评估建议报告可用于指导开展数字素养的培育和评估工作。报告介绍了由框架映射、应用映射、深度咨询和在线咨询四个研究环节组成的框架制定过程,描述了学习者必备的设备与软件操作、信息与数据素养、沟通与协作、数字内容创建、数字安全、问题解决和职业相关能力七个数字能力域,提出了使用自我报告作为主要评估形式,使用在线知识测试作为辅助评估形式,实施预评估并建立指导小组三条评估建议。全球数字素养框架及其评估研究的方法和经验值得我国借鉴。展开更多
Four wetland maps for all China have been produced,based on Landsat and CBERS-02B remote sensing data between 1978 and 2008 (1978,1990,2000 and 2008).These maps were mainly developed by manual interpretation and valid...Four wetland maps for all China have been produced,based on Landsat and CBERS-02B remote sensing data between 1978 and 2008 (1978,1990,2000 and 2008).These maps were mainly developed by manual interpretation and validated by substantial field investigation in 2009.Based on these maps,we analyzed the 2008 wetland distribution in China and discussed wetland changes and their drivers over the past 30 years.(i) There were about 324097 km 2 of wetlands in 2008,for which inland marshes or swamps were the most common wetland type (35%),with lakes (26%) second.Most of the wetlands were in Heilongjiang,Inner Mongolia,Qinghai and Tibet,occupying about 55% of the national wetland area.(ii) From 1978 to 2008,China's wetland area continually and significantly decreased,by about 33% based on changes in the wetland map.This was in sharp contrast to the increase in artificial wetlands,which increased by about 122%.Inland marshes accounted for the main loss of total wetlands from 1978 to 2000.From 2000 through 2008,riverine and lacustrine wetlands constituted the main wetland loss.Fortunately however,the rate of wetland loss decreased from 5523 to 831 km 2 /a.(iii) The change ratio of lost natural wetlands (including inland and coastal wetlands) to non-wetlands has decreased slightly over the past 30 years.From 1978 to 1990,nearly all natural wetlands (98%) lost were transformed into non-wetlands.However,the ratio declined to 86% from 1990 to 2000,and to 77% from 2000 to 2008.(iv) All Chinese provinces were divided into three groups according to patterns of wetland changes,which could relate to the driving forces of such changes.Tibet was completely different from other provinces,as it was one representative example in which there was a net wetland increase,because of global warming and decreased human activity since 1990.Increased economic development caused considerable wetland loss in most eastern provinces,and artificial wetlands increased.展开更多
文摘数字合作时代的到来,对学习者的数字素养要求也提高了。联合国教科文组织发布的《全球数字素养框架》(Digital Literacy Global Framework,简称DLGF)及其评估建议报告可用于指导开展数字素养的培育和评估工作。报告介绍了由框架映射、应用映射、深度咨询和在线咨询四个研究环节组成的框架制定过程,描述了学习者必备的设备与软件操作、信息与数据素养、沟通与协作、数字内容创建、数字安全、问题解决和职业相关能力七个数字能力域,提出了使用自我报告作为主要评估形式,使用在线知识测试作为辅助评估形式,实施预评估并建立指导小组三条评估建议。全球数字素养框架及其评估研究的方法和经验值得我国借鉴。
基金supported by the National High-tech R&D Program of China(2009AA122003)
文摘Four wetland maps for all China have been produced,based on Landsat and CBERS-02B remote sensing data between 1978 and 2008 (1978,1990,2000 and 2008).These maps were mainly developed by manual interpretation and validated by substantial field investigation in 2009.Based on these maps,we analyzed the 2008 wetland distribution in China and discussed wetland changes and their drivers over the past 30 years.(i) There were about 324097 km 2 of wetlands in 2008,for which inland marshes or swamps were the most common wetland type (35%),with lakes (26%) second.Most of the wetlands were in Heilongjiang,Inner Mongolia,Qinghai and Tibet,occupying about 55% of the national wetland area.(ii) From 1978 to 2008,China's wetland area continually and significantly decreased,by about 33% based on changes in the wetland map.This was in sharp contrast to the increase in artificial wetlands,which increased by about 122%.Inland marshes accounted for the main loss of total wetlands from 1978 to 2000.From 2000 through 2008,riverine and lacustrine wetlands constituted the main wetland loss.Fortunately however,the rate of wetland loss decreased from 5523 to 831 km 2 /a.(iii) The change ratio of lost natural wetlands (including inland and coastal wetlands) to non-wetlands has decreased slightly over the past 30 years.From 1978 to 1990,nearly all natural wetlands (98%) lost were transformed into non-wetlands.However,the ratio declined to 86% from 1990 to 2000,and to 77% from 2000 to 2008.(iv) All Chinese provinces were divided into three groups according to patterns of wetland changes,which could relate to the driving forces of such changes.Tibet was completely different from other provinces,as it was one representative example in which there was a net wetland increase,because of global warming and decreased human activity since 1990.Increased economic development caused considerable wetland loss in most eastern provinces,and artificial wetlands increased.
