Characteristics of phosphorus in sediments of the Sancha Lake in Sichuan province and their relationship with human activity

Author(s):  
Binyang Jia ◽  
Ya Tang ◽  
Yan Zhan ◽  
Hongbing Luo
2019 ◽  
Vol 11 (19) ◽  
pp. 5308 ◽  
Author(s):  
Chuangjuan Zhang ◽  
Hongming He ◽  
Ali Mokhtar

Agricultural lands are very sensitive to climate and human activity changes, which result in variations in regional agricultural resources and decreased production of total grain output and increased difficulty in producing grain yields. Multiple cropping is one of the simplest ways to increase grain production. The research aims is to analyze the spatial and temporal variations in the multiple cropping index and study the factors that influence the multiple cropping index. Based on the maximum multiple cropping index (MCI) and a “heat-precipitation” quantitative relation model, we analyzed the theoretical potential multiple cropping index (PMCI) and the spatiotemporal changes in the potential increase in the multiple cropping index (PIMCI). Our results are as follows: The MCI was significantly higher in the eastern region than in the western region and higher in the central region than in the northern and southern regions; in Yunnan Province, it showed a fluctuating downwards trend; further, it exhibited sudden declines from 2004 to 2006 and from 2012 to 2014 in Guizhou, while it exhibited an increasing trend in Sichuan Province. The PMCIs were the highest in the eastern and southern regions, especially in eastern Sichuan Province, and the PIMCI was significantly higher in Yunnan Province than in Guizhou and Sichuan. Climate change, human activities, and terrain had significant influences on the MCI changes in southwest China, especially the temperature change, which was the key factor affecting the MCI changes. The dominant land use types in southwest China were forest (46%), grass (28%), and farmland (23%) during 1980–2015. Therefore, the adjustment of the planting structure in different terrain areas according to the temperature changes has become the main strategy to promote the sustainable development of cultivated land resources in the region, further, the results would help implement the plan to increase grain production capacity in southwest China.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Yi Bao ◽  
Xuemei Yun ◽  
Chaohong Zhao ◽  
Fang Wang ◽  
Yuesheng Li

Abstract Jade, which is one of the most characteristic materials constituting Chinese artifacts, signifies cultural differences between ancient Chinese and western civilizations. One of the most important typical characteristics of ancient jade artifacts recovered through archeological excavations is color alterations due to human activity and natural weathering, which has led to an area of intensive research in archeology. “Alteration” refers to chemical component and structural changes in jade artifacts caused by human activity and natural weathering, which is different from the term in geology. In this study, Raman spectroscopy was used to analyze six color alterations on ancient jade artifacts unearthed from the Jinsha Site in Sichuan Province, a region famous for artifacts with colorful alterations. The colorful alterations were observed to originate from corrosion products of bronzeware. The green, black, yellow, blue, purple, and white alterations were due to malachite, tenorite, pyromorphite, azurite, diaboleite, and cassiterite, respectively. Meanwhile, organic matter and hypertoxic arsenolite were first found on ancient jade artifacts.


2007 ◽  
Author(s):  
Luci Fuscaldi Teixeira-Salmela ◽  
Sandra J. Olney ◽  
Revathy Devaraj

2019 ◽  
Author(s):  
Grant Duffy ◽  
Jasmine R Lee

Warming across ice-covered regions will result in changes to both the physical and climatic environment, revealing new ice-free habitat and new climatically suitable habitats for non-native species establishment. Recent studies have independently quantified each of these aspects in Antarctica, where ice-free areas form crucial habitat for the majority of terrestrial biodiversity. Here we synthesise projections of Antarctic ice-free area expansion, recent spatial predictions of non-native species risk, and the frequency of human activities to quantify how these facets of anthropogenic change may interact now and in the future. Under a high-emissions future climate scenario, over a quarter of ice-free area and over 80 % of the ~14 thousand km2 of newly uncovered ice-free area could be vulnerable to invasion by one or more of the modelled non-native species by the end of the century. Ice-free areas identified as vulnerable to non-native species establishment were significantly closer to human activity than unsuitable areas were. Furthermore, almost half of the new vulnerable ice-free area is within 20 km of a site of current human activity. The Antarctic Peninsula, where human activity is heavily concentrated, will be at particular risk. The implications of this for conservation values of Antarctica and the management efforts required to mitigate against it are in need of urgent consideration.


Author(s):  
Pierre Aubenque

Pierre Aubenque’s “Science Regained” (1962; translated by Clayton Shoppa) was originally published as the concluding chapter of Le Problème de l’Être chez Aristote, one of the most important and original books on Aristotle’s Metaphysics. In this essay, Aubenque contends that the impasses which beset the project of first philosophy paradoxically become its greatest accomplishments. Although science stabilizes motion and thereby introduces necessity into human cognition, human thought always occurs amidst an inescapable movement of change and contingency. Aristotle’s ontology, as a discourse that strives to achieve being in its unity, succeeds by means of the failure of the structure of its own approach: the search of philosophy – dialectic – becomes the philosophy of the search. Aubenque traces this same structure of scission, mediation, and recovery across Aristotelian discussions of theology, motion, time, imitation, and human activity.


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