The Flexible Global Ocean-Atmosphere-Land System Model-gamil (FGOALS-g) was used to study the spring prediction barrier (SPB) in an ensemble system. This coupled model was developed and maintained at the State Key Lab...The Flexible Global Ocean-Atmosphere-Land System Model-gamil (FGOALS-g) was used to study the spring prediction barrier (SPB) in an ensemble system. This coupled model was developed and maintained at the State Key Laboratory of Atmospheric Sciences and Geophysical Fluid Dynamics (LASG). There are two steps in our hindcast experiments. The first is to integrate the coupled model continuously with sea surface temperature (SST) nudging, from 1971 to 2006. The second is to carry out a series of one-year hindcasts without SST nudging, by adopting initial values from the first step on January 1 st , April 1st , July 1st , and October 1st , from 1982 to 2005. We generate 10 ensemble members for a particular start date (1st ) by choosing different atmospheric and land conditions around the hindcast start date (1st through 10th ). To estimate the predicted SST, two methods are used: (1) Anomaly Correlation Coefficient and its rate of decrease; and (2) Talagrand distribution and its standard deviation. Results show that FGOALS-g offers a reliable ensemble system with realistic initial atmospheric and oceanic conditions, and high anomaly correlation (>0.5) within 6 month lead time. Further, the ensemble approach is effective, in that the anomaly correlation of ensemble mean is much higher than that of most individual ensemble members. The SPB exists in the FGOALS-g ensemble system, as shown by anomaly correlation and equal likelihood. Nevertheless, the role of the ensemble mean in reducing the SPB of ENSO prediction is significant. The rate of decrease of the ensemble mean is smaller than the largest deviations by 0.04-0.14. At the same time, the ensemble system "equal likelihood" declines during spring. An ensemble mean helps give a correct prediction direction, departing from largely-deviated ensemble members.展开更多
South Africa is facing enormous financial, environmental and social challenges posed by abandoned mines. This investigation focused on field verification of 850 abandoned mines and associated rehabilitation challenges...South Africa is facing enormous financial, environmental and social challenges posed by abandoned mines. This investigation focused on field verification of 850 abandoned mines and associated rehabilitation challenges in the Limpopo Province. The investigations included desktop studies, standardised field-based ranking system and sampling. The waste material samples were analysed using XRF （X-ray fluorescence spectrometry） at the Council for Geoscience Laboratory. Approximately 5% of 850 abandoned mines in the Limpopo Province require urgent rehabilitation either due to high concentrations of metals from mine dumps or presence of open shafts. For example, copper concentrations at Messina and Spoedwel were 9,719 ppm and 56,160 ppm, respectively. Birthday Gold Mine in Giyani area is characterised by un-safe open shafts and un-stable grounds which poses safety problems and limits the future land-use. Although these investigations have been conducted, it is not possible to rehabilitate all abandoned mines mainly due to limited financial resources. The abandoned mines close to human settlement are given priority due to their immediate threat to people. This study recommends that rehabilitation of abandoned mines should take cognisance of the sustainable future land use that will favour the creation of jobs and nature conservation.展开更多
Assessing subsurface characteristics and imaging geologic features （e.g., faults, cavities, low-velocity lay- ers, etc.） are typical problems in near-surface geophysics. These questions often have adverse geotechni-...Assessing subsurface characteristics and imaging geologic features （e.g., faults, cavities, low-velocity lay- ers, etc.） are typical problems in near-surface geophysics. These questions often have adverse geotechni-cal engineering implications, and can be especially acute when associated with high-hazard structures such as large earthen flood-control dams. Dam-related issues are becoming more frequent in the United States, because a large part of this major infrastructure was designed and constructed in the early- to mid-twentieth century; these dams are thus passing into the latter stages of their design life, where minute flaws that were overlooked or thought to be insignificant in design/construction are now proving problematic. The high-hydraulic heads associated with these structures can quicken degra-dation of weak areas and compromise long-term integrity. Addressing dam-related problems solely with traditional invasive drilling techniques is often inadequate （i.e., lack of lateral resolution） and]or econom- ically exorbitant at this scale. However, strategic geotechnical drilling integrated with the broad utility of near-surface geophysics, particularly the horizontally polarized shear-wave （SH-mode） seismic-reflection technique for imaging the internal structural detail and geological foundation conditions of earthfill embankment dams can cost-effectively improve the overall subsurface definition needed for remedial engineering. Demonstrative evidence for this supposition is provided in the form of SH-wave seismic-reflection imaging of in situ and engineered as-built components of flood-control embankment dams at two example sites in the central United States.展开更多
Scientific Land Reform is at centre of decades＇ conflict and even during Peace Process in Nepal. In this regards, land reform attempts to address equity and efficiency so as to address historical inequity and injusti...Scientific Land Reform is at centre of decades＇ conflict and even during Peace Process in Nepal. In this regards, land reform attempts to address equity and efficiency so as to address historical inequity and injustices for promoting peace process in Nepal. From equity perspective, landlessness, unequal power structure and social relation, injustices and discrimination for long centuries are key land issues. Along with this, economic efficiency is the fundamental for enhancing agricultural growth leading to economic growth. In particular, this article argues that, in the given prevailing condition, i.e. traditional and subsistence and rampant rural poverty and unequal power structure and injustices, small farms perform better leading to food and livelihood security at household level. Consequently, ＇Scientific Land Reform＇ has been defined by taking into account the essence of equity and efficiency.展开更多
Integrated River Basin Management(IRBM)has been a long discussed way to sustainably manage water and land resources;yet,very few examples of effective IRBM are found because there is a lack of sufficient scientific su...Integrated River Basin Management(IRBM)has been a long discussed way to sustainably manage water and land resources;yet,very few examples of effective IRBM are found because there is a lack of sufficient scientific support,as well as institutional accommodation,to successfully implement it.This paper overviews the major challenges with IRBM,the promising scientific approaches for the implementation of IRBM,and the areas of needed research,with considerable issues and experiences from China.It is expected that novel research will draw together disparate disciplines into an integrated scientific framework,upon which better modeling tools,stakeholder involvement,and decision-making support can be built.Cutting-edge new technologies will bring ideas of IRBM forward to theory and finally to practice.The paper will prompt scientists to undertake research to fill in the gaps in the current IRBM knowledge base and provide practitioners guidance on how to incorporate scientifically based information within the IRBM decision process.展开更多
1 Background Taxonomy is the branch of science dedicated to discovering,characterizing,naming,and classifying objects or organisms so as to understand relationships between them and the factors of their formation.The ...1 Background Taxonomy is the branch of science dedicated to discovering,characterizing,naming,and classifying objects or organisms so as to understand relationships between them and the factors of their formation.The aims of classification are to identify and understand the objects for establishing an orderly system for the grouping objects.展开更多
基金Supported by the National Basic Research Program of China (973 Program)(No. 2007CB411806)the Knowledge Innovation Program of Chinese Academy of Sciences (Nos. KZCX2-YW-Q11-02, XDA05090404)+1 种基金the National Natural Science Foundation of China (No. 40975065)the National High Technology Research and Development Program of China(863 Program) (No. 2010AA012304)
文摘The Flexible Global Ocean-Atmosphere-Land System Model-gamil (FGOALS-g) was used to study the spring prediction barrier (SPB) in an ensemble system. This coupled model was developed and maintained at the State Key Laboratory of Atmospheric Sciences and Geophysical Fluid Dynamics (LASG). There are two steps in our hindcast experiments. The first is to integrate the coupled model continuously with sea surface temperature (SST) nudging, from 1971 to 2006. The second is to carry out a series of one-year hindcasts without SST nudging, by adopting initial values from the first step on January 1 st , April 1st , July 1st , and October 1st , from 1982 to 2005. We generate 10 ensemble members for a particular start date (1st ) by choosing different atmospheric and land conditions around the hindcast start date (1st through 10th ). To estimate the predicted SST, two methods are used: (1) Anomaly Correlation Coefficient and its rate of decrease; and (2) Talagrand distribution and its standard deviation. Results show that FGOALS-g offers a reliable ensemble system with realistic initial atmospheric and oceanic conditions, and high anomaly correlation (>0.5) within 6 month lead time. Further, the ensemble approach is effective, in that the anomaly correlation of ensemble mean is much higher than that of most individual ensemble members. The SPB exists in the FGOALS-g ensemble system, as shown by anomaly correlation and equal likelihood. Nevertheless, the role of the ensemble mean in reducing the SPB of ENSO prediction is significant. The rate of decrease of the ensemble mean is smaller than the largest deviations by 0.04-0.14. At the same time, the ensemble system "equal likelihood" declines during spring. An ensemble mean helps give a correct prediction direction, departing from largely-deviated ensemble members.
文摘South Africa is facing enormous financial, environmental and social challenges posed by abandoned mines. This investigation focused on field verification of 850 abandoned mines and associated rehabilitation challenges in the Limpopo Province. The investigations included desktop studies, standardised field-based ranking system and sampling. The waste material samples were analysed using XRF （X-ray fluorescence spectrometry） at the Council for Geoscience Laboratory. Approximately 5% of 850 abandoned mines in the Limpopo Province require urgent rehabilitation either due to high concentrations of metals from mine dumps or presence of open shafts. For example, copper concentrations at Messina and Spoedwel were 9,719 ppm and 56,160 ppm, respectively. Birthday Gold Mine in Giyani area is characterised by un-safe open shafts and un-stable grounds which poses safety problems and limits the future land-use. Although these investigations have been conducted, it is not possible to rehabilitate all abandoned mines mainly due to limited financial resources. The abandoned mines close to human settlement are given priority due to their immediate threat to people. This study recommends that rehabilitation of abandoned mines should take cognisance of the sustainable future land use that will favour the creation of jobs and nature conservation.
文摘Assessing subsurface characteristics and imaging geologic features （e.g., faults, cavities, low-velocity lay- ers, etc.） are typical problems in near-surface geophysics. These questions often have adverse geotechni-cal engineering implications, and can be especially acute when associated with high-hazard structures such as large earthen flood-control dams. Dam-related issues are becoming more frequent in the United States, because a large part of this major infrastructure was designed and constructed in the early- to mid-twentieth century; these dams are thus passing into the latter stages of their design life, where minute flaws that were overlooked or thought to be insignificant in design/construction are now proving problematic. The high-hydraulic heads associated with these structures can quicken degra-dation of weak areas and compromise long-term integrity. Addressing dam-related problems solely with traditional invasive drilling techniques is often inadequate （i.e., lack of lateral resolution） and]or econom- ically exorbitant at this scale. However, strategic geotechnical drilling integrated with the broad utility of near-surface geophysics, particularly the horizontally polarized shear-wave （SH-mode） seismic-reflection technique for imaging the internal structural detail and geological foundation conditions of earthfill embankment dams can cost-effectively improve the overall subsurface definition needed for remedial engineering. Demonstrative evidence for this supposition is provided in the form of SH-wave seismic-reflection imaging of in situ and engineered as-built components of flood-control embankment dams at two example sites in the central United States.
文摘Scientific Land Reform is at centre of decades＇ conflict and even during Peace Process in Nepal. In this regards, land reform attempts to address equity and efficiency so as to address historical inequity and injustices for promoting peace process in Nepal. From equity perspective, landlessness, unequal power structure and social relation, injustices and discrimination for long centuries are key land issues. Along with this, economic efficiency is the fundamental for enhancing agricultural growth leading to economic growth. In particular, this article argues that, in the given prevailing condition, i.e. traditional and subsistence and rampant rural poverty and unequal power structure and injustices, small farms perform better leading to food and livelihood security at household level. Consequently, ＇Scientific Land Reform＇ has been defined by taking into account the essence of equity and efficiency.
基金supported by U.S.National Science Foundation(Grant No.CBET-0747276)
文摘Integrated River Basin Management(IRBM)has been a long discussed way to sustainably manage water and land resources;yet,very few examples of effective IRBM are found because there is a lack of sufficient scientific support,as well as institutional accommodation,to successfully implement it.This paper overviews the major challenges with IRBM,the promising scientific approaches for the implementation of IRBM,and the areas of needed research,with considerable issues and experiences from China.It is expected that novel research will draw together disparate disciplines into an integrated scientific framework,upon which better modeling tools,stakeholder involvement,and decision-making support can be built.Cutting-edge new technologies will bring ideas of IRBM forward to theory and finally to practice.The paper will prompt scientists to undertake research to fill in the gaps in the current IRBM knowledge base and provide practitioners guidance on how to incorporate scientifically based information within the IRBM decision process.
文摘1 Background Taxonomy is the branch of science dedicated to discovering,characterizing,naming,and classifying objects or organisms so as to understand relationships between them and the factors of their formation.The aims of classification are to identify and understand the objects for establishing an orderly system for the grouping objects.
