As an important traditional labor-intensive industry of both India and China, the cocoon silk industry has long made great contributions to the ecological environment protection, rural economic development and the inc...As an important traditional labor-intensive industry of both India and China, the cocoon silk industry has long made great contributions to the ecological environment protection, rural economic development and the increase in export income of both countries. India is not only a very important cocoon silk trading partner, but an important production competitor of China. In recent years, there has been a large increase in the production and trade of the cocoon silk between China and India; however, China relies heavily on Indian market, which leads to a tendency of further deterioration in the silk trade environment between both countries. The present article makes an empirical study of the cocoon silk resources of the two countries and the scale, product mix and market structure of China-Indian silk trade from 2001 to 2007. Overall silk trading volumes from China to India and market concentration rate are on the increase because of the superiority of Chinese cocoon silk production over that of India. Owing to scattered market share and export that mainly focused on raw materials product, there has been a phenomenon of price reduction and quantity increase. India carries out fierce competition with China in the international market and even imposes antidumping sanction on Chinese silk, which are key factors restricting further increase between China-India trade. Based on the abovementioned facts, the authors aim to put forward suggestions for steadily developing the production and trade of China's silk.展开更多
In order to quantify the virtual water part which is contained in the imported cereals, compared with the hydraulic potentialities which are annually mobilised through the national territory, and on the basis of the a...In order to quantify the virtual water part which is contained in the imported cereals, compared with the hydraulic potentialities which are annually mobilised through the national territory, and on the basis of the agricultural statistics, we have determined the average quantities of the imported cereals per year in order to determine the virtual water volume that these cereals bind. The water needs of the cereals which are produced in Algeria have been calculated by the Cropwat software, in order to define the equivalent quantities of water in their production on the national scale. The obtained results confirm the importance of the annually imported virtual water, through the imported cereals, comparing with the national hydraulic potentialities. Our study shows also that in spite of the strategic importance of the virtual water in the imported cereals, a diminution has to take place, on the average term, by an improvement of the use efficiency of the precipitations （green virtual water） using the best mastery of the technical itinerary in general, and also the efficient use of precipitations in particular.展开更多
Sahlbergella singularis （brown cocoa mirid） is responsible for over 30% yield loss of cocoa, while Phytophthora megakarya （causal organism of black pod disease） causes between 70-100% yield loss of cocoa in Nigeri...Sahlbergella singularis （brown cocoa mirid） is responsible for over 30% yield loss of cocoa, while Phytophthora megakarya （causal organism of black pod disease） causes between 70-100% yield loss of cocoa in Nigeria. In all the Nigerian cocoa agroecological zones, the use of pesticides still remains an important component among the strategies for effective control of major insect pests and diseases of cocoa. The Cocoa Research Institute of Nigeria （CRIN）, has the national mandate to evaluate and recommend novel pesticides from various groups that fall within the European-Union standards for use on cocoa farms in Nigeria. Such pesticides usually undergo rigorous testing spanning over 3 years to determine correct dose necessary to produce toxic reactions to the targeted pests without any adverse effects on the environment, man and non-target organisms. The screening exercise for candidate pesticides starts with confirmatory test of the constituent active ingredient, laboratory bioassay, phytotoxicity test, first, second and third year field evaluation and residue analysis of beans harvested from the treated plots. This paper critically examines these standard procedures, which must be followed judiciously for novel pesticides certification and recommendation for use in Nigeria.展开更多
Global warming, as a result of an increase in the mean temperature of the planet, might lead to catastrophic events for humanity. This temperature increase is mainly the result of an increase in the atmospheric greenh...Global warming, as a result of an increase in the mean temperature of the planet, might lead to catastrophic events for humanity. This temperature increase is mainly the result of an increase in the atmospheric greenhouse gases （GHG） concentration. Water vapor, carbon dioxide （CO2）, methane （CH4） and nitrous oxide （N20） are the most important GHG, and human activities, such as industry, livestock and agriculture, contribute to the production of these gases. Methane, at an atmospheric concentration of 1.7 gmol tool-1 currently, is responsible for 16% of the global warming due to its relatively high global warming potential. Soils play an important role in the CH4 cycle as methanotrophy （oxidation of CH4） and methanogenesis （production of CH4） take place in them. Understanding methanogenesis and methanotrophy is essential to establish new agriculture techniques and industrial processes that contribute to a better balance of GHG. The current knowledge of methanogenesis and methanotrophy in soils, anaerobic CH4 oxidation and methanotrophy in extreme environments is also discussed.展开更多
文摘As an important traditional labor-intensive industry of both India and China, the cocoon silk industry has long made great contributions to the ecological environment protection, rural economic development and the increase in export income of both countries. India is not only a very important cocoon silk trading partner, but an important production competitor of China. In recent years, there has been a large increase in the production and trade of the cocoon silk between China and India; however, China relies heavily on Indian market, which leads to a tendency of further deterioration in the silk trade environment between both countries. The present article makes an empirical study of the cocoon silk resources of the two countries and the scale, product mix and market structure of China-Indian silk trade from 2001 to 2007. Overall silk trading volumes from China to India and market concentration rate are on the increase because of the superiority of Chinese cocoon silk production over that of India. Owing to scattered market share and export that mainly focused on raw materials product, there has been a phenomenon of price reduction and quantity increase. India carries out fierce competition with China in the international market and even imposes antidumping sanction on Chinese silk, which are key factors restricting further increase between China-India trade. Based on the abovementioned facts, the authors aim to put forward suggestions for steadily developing the production and trade of China's silk.
文摘In order to quantify the virtual water part which is contained in the imported cereals, compared with the hydraulic potentialities which are annually mobilised through the national territory, and on the basis of the agricultural statistics, we have determined the average quantities of the imported cereals per year in order to determine the virtual water volume that these cereals bind. The water needs of the cereals which are produced in Algeria have been calculated by the Cropwat software, in order to define the equivalent quantities of water in their production on the national scale. The obtained results confirm the importance of the annually imported virtual water, through the imported cereals, comparing with the national hydraulic potentialities. Our study shows also that in spite of the strategic importance of the virtual water in the imported cereals, a diminution has to take place, on the average term, by an improvement of the use efficiency of the precipitations （green virtual water） using the best mastery of the technical itinerary in general, and also the efficient use of precipitations in particular.
文摘Sahlbergella singularis （brown cocoa mirid） is responsible for over 30% yield loss of cocoa, while Phytophthora megakarya （causal organism of black pod disease） causes between 70-100% yield loss of cocoa in Nigeria. In all the Nigerian cocoa agroecological zones, the use of pesticides still remains an important component among the strategies for effective control of major insect pests and diseases of cocoa. The Cocoa Research Institute of Nigeria （CRIN）, has the national mandate to evaluate and recommend novel pesticides from various groups that fall within the European-Union standards for use on cocoa farms in Nigeria. Such pesticides usually undergo rigorous testing spanning over 3 years to determine correct dose necessary to produce toxic reactions to the targeted pests without any adverse effects on the environment, man and non-target organisms. The screening exercise for candidate pesticides starts with confirmatory test of the constituent active ingredient, laboratory bioassay, phytotoxicity test, first, second and third year field evaluation and residue analysis of beans harvested from the treated plots. This paper critically examines these standard procedures, which must be followed judiciously for novel pesticides certification and recommendation for use in Nigeria.
基金Supported by the Centro de Investigación y de Estudios Avanzados del IPN,Mexico and the Consejo Nacional de Ciencia y Tecnología,Mexico(Nos.153216,232468 and 245119)
文摘Global warming, as a result of an increase in the mean temperature of the planet, might lead to catastrophic events for humanity. This temperature increase is mainly the result of an increase in the atmospheric greenhouse gases （GHG） concentration. Water vapor, carbon dioxide （CO2）, methane （CH4） and nitrous oxide （N20） are the most important GHG, and human activities, such as industry, livestock and agriculture, contribute to the production of these gases. Methane, at an atmospheric concentration of 1.7 gmol tool-1 currently, is responsible for 16% of the global warming due to its relatively high global warming potential. Soils play an important role in the CH4 cycle as methanotrophy （oxidation of CH4） and methanogenesis （production of CH4） take place in them. Understanding methanogenesis and methanotrophy is essential to establish new agriculture techniques and industrial processes that contribute to a better balance of GHG. The current knowledge of methanogenesis and methanotrophy in soils, anaerobic CH4 oxidation and methanotrophy in extreme environments is also discussed.
