As one of the world well-known high-stakes tests, CET-4 (College English Test Band 4) changed from being generally accepted to being widely questioned in the past 25 years. In spite of a series of reforms of CET-4, ...As one of the world well-known high-stakes tests, CET-4 (College English Test Band 4) changed from being generally accepted to being widely questioned in the past 25 years. In spite of a series of reforms of CET-4, the negative impact of CET-4 remains intense. Three main reasons are probed into here. Firstly, the objective of CET-4 is ambiguous. Secondly, the test objective does not accord with teaching objective. Finally, test contents do not match well with the practical language use. To improve the present passive state of CET-4, some suggestions are given.展开更多
Preserving Tibet’s unique history and cultural heritage relies on the sustainability of the Tibetan croplands,which are characterized by highland barley,the only cereal crop cultivated over 4000 m above sea level.Yet...Preserving Tibet’s unique history and cultural heritage relies on the sustainability of the Tibetan croplands,which are characterized by highland barley,the only cereal crop cultivated over 4000 m above sea level.Yet it is unknown how these croplands will respond to climate change.Here,using yield statistics from 1985 to 2015,we found that the impact of temperature anomalies on the Tibetan crop yield shifted from nonsignificant(P>0.10)in the 1980s and 1990s to significantly negative(P<0.05)in recent years.Meanwhile,the apparent sensitivity of the crop yield to temperature anomalies almost doubled,from(–0.13±0.20)to(–0.22±0.14)t·ha^(-1)℃^(–1).The emerging negative impacts of higher temperatures suggest an increasing vulnerability of Tibetan croplands to warmer climate.With global warming scenarios of+1.5 or+2.0℃above the pre-industry level,the temperature sensitivities of crop yield may further increase to(–0.33±0.10)and(–0.51±0.18)t·ha^(-1)℃^(–1),respectively,making the crops 2–3 times more vulnerable to warmer temperatures than they are today.展开更多
Extraction of mineral resources is the backbone of the national economy in many developed and developing countries of the world. However, the exploitation can have many negative impacts on the immediate environment of...Extraction of mineral resources is the backbone of the national economy in many developed and developing countries of the world. However, the exploitation can have many negative impacts on the immediate environment of the exploitation sites. In this study performed on some mining areas of the Moroccan Anti-Atlas, four principal negative effects were detected: effect on the physiognomy, on safety, on health, and on recovery rate. The principal source of this situation is the exploitation of the ore deposits from top to bottom without using any geological preparation and the use of non-adapted exploitation technics. To minimize these impacts, we propose to establish a geological study and advanced mining exploration before starting exploitation, and follow an exploitation technic well adapted to the morphology of the ore deposit like cut-and-fill mining and sublevel stoping methods.展开更多
This article aims to give the reader an overview of the development of nature tourism and its importance for the sustainability of rural and natural areas involving special protection. Once you have seen the end of ma...This article aims to give the reader an overview of the development of nature tourism and its importance for the sustainability of rural and natural areas involving special protection. Once you have seen the end of mass tourism, tourism demand is much more heterogeneous and attends a difference of purposes for which such demand is diversified, representing a particularly important tourism and leisure activities that take place now in natural areas, thus giving rise to different types of leisure and tourism, such as Rural tourism, Ecotourism, Agrotourism, Nature and Adventures tourism, Sports tourism in natural areas, etc. What is important for the sustainability of these areas, that are subject to this type of tourism is getting some positive impacts maintaining sustainability and combating the negative impact, that such activities may have on certain protected areas or special conservation. From this point of view, we believe it is important to develop responsible tourism and committed to environmental conservation and for that the local population must be trained in order to achieve development of the territory without the activities that are the fruit of these typologies tourism and leisure pose a danger. Also, the tourist population must be more aware about what constitutes such practices of leisure and tourism for conservation of the environment and, at the same time, the development of the most depressed areas.展开更多
文摘As one of the world well-known high-stakes tests, CET-4 (College English Test Band 4) changed from being generally accepted to being widely questioned in the past 25 years. In spite of a series of reforms of CET-4, the negative impact of CET-4 remains intense. Three main reasons are probed into here. Firstly, the objective of CET-4 is ambiguous. Secondly, the test objective does not accord with teaching objective. Finally, test contents do not match well with the practical language use. To improve the present passive state of CET-4, some suggestions are given.
基金the Second Tibetan Plateau Scien-tific Expedition and Research Program(2019QZKK0405)the National Natural Science Foundation of China project Basic Science Center for Tibetan Plateau Earth System(41988101).
文摘Preserving Tibet’s unique history and cultural heritage relies on the sustainability of the Tibetan croplands,which are characterized by highland barley,the only cereal crop cultivated over 4000 m above sea level.Yet it is unknown how these croplands will respond to climate change.Here,using yield statistics from 1985 to 2015,we found that the impact of temperature anomalies on the Tibetan crop yield shifted from nonsignificant(P>0.10)in the 1980s and 1990s to significantly negative(P<0.05)in recent years.Meanwhile,the apparent sensitivity of the crop yield to temperature anomalies almost doubled,from(–0.13±0.20)to(–0.22±0.14)t·ha^(-1)℃^(–1).The emerging negative impacts of higher temperatures suggest an increasing vulnerability of Tibetan croplands to warmer climate.With global warming scenarios of+1.5 or+2.0℃above the pre-industry level,the temperature sensitivities of crop yield may further increase to(–0.33±0.10)and(–0.51±0.18)t·ha^(-1)℃^(–1),respectively,making the crops 2–3 times more vulnerable to warmer temperatures than they are today.
文摘Extraction of mineral resources is the backbone of the national economy in many developed and developing countries of the world. However, the exploitation can have many negative impacts on the immediate environment of the exploitation sites. In this study performed on some mining areas of the Moroccan Anti-Atlas, four principal negative effects were detected: effect on the physiognomy, on safety, on health, and on recovery rate. The principal source of this situation is the exploitation of the ore deposits from top to bottom without using any geological preparation and the use of non-adapted exploitation technics. To minimize these impacts, we propose to establish a geological study and advanced mining exploration before starting exploitation, and follow an exploitation technic well adapted to the morphology of the ore deposit like cut-and-fill mining and sublevel stoping methods.
文摘This article aims to give the reader an overview of the development of nature tourism and its importance for the sustainability of rural and natural areas involving special protection. Once you have seen the end of mass tourism, tourism demand is much more heterogeneous and attends a difference of purposes for which such demand is diversified, representing a particularly important tourism and leisure activities that take place now in natural areas, thus giving rise to different types of leisure and tourism, such as Rural tourism, Ecotourism, Agrotourism, Nature and Adventures tourism, Sports tourism in natural areas, etc. What is important for the sustainability of these areas, that are subject to this type of tourism is getting some positive impacts maintaining sustainability and combating the negative impact, that such activities may have on certain protected areas or special conservation. From this point of view, we believe it is important to develop responsible tourism and committed to environmental conservation and for that the local population must be trained in order to achieve development of the territory without the activities that are the fruit of these typologies tourism and leisure pose a danger. Also, the tourist population must be more aware about what constitutes such practices of leisure and tourism for conservation of the environment and, at the same time, the development of the most depressed areas.