The occurrence rules of major diseases and pests in rice were investigated under six cultivation patterns, i.e., mechanical plowing-artificial transplanting, mechanical plowing-mechanical transplanting, mechanical plo...The occurrence rules of major diseases and pests in rice were investigated under six cultivation patterns, i.e., mechanical plowing-artificial transplanting, mechanical plowing-mechanical transplanting, mechanical plowing-scattered transplanting,cattle plowing-artificial transplanting, cattle plowing-mechanical transplanting and cattle plowing-scattered transplanting. The results showed that the six cultivation patterns showed small effects on the occurrence of rice sheath blight, second-generation rice planthopper, rice stem borer and rice false smut, but showed great effects on the occurrence of rice leaf folder, third-and fourth-generation rice planthopper and weeds; there were certain differences in the rice yield among different cultivation patterns, and the rice yield under the pattern of mechanical plowing-mechanical transplanting ranked first, while that under the pattern of cattle plowing-scattered transplanting ranked last.展开更多
[Objective] This study aimed to investigate the combined effects of sowing date, plant density, nitrogenous fertilizer, phosphorus fertilizer and potassium fertilizer on quality parameters of high grade hybrid rapesee...[Objective] This study aimed to investigate the combined effects of sowing date, plant density, nitrogenous fertilizer, phosphorus fertilizer and potassium fertilizer on quality parameters of high grade hybrid rapeseed. [Method] By using Youyan 599 and Sanbei 98 as experimental materials, quadratic orthogonal rotation combination with five factors was designed for this study. [Result] Erucic acid content was nega- tively correlated with sowing date and nitrogen fertilizer, positively correlated with plant density. Glucosinolate content was negatively correlated with sowing date, positively correlated with potash fertilizer amount. Oil content was negatively correlated with sowing date and nitrogen fertilizer amount, positively correlated with plant density and potash fertilizer amount. Protein content was positively correlated with sowing date and nitrogen fertilizer amount, negatively correlated with plant density and potash fer- tilizer amount. Oleic acid content was negatively correlated with phosphate fertilizer amount, positively correlated with nitrogen fertilizer amount. Palmitic acid was nega- tively correlated with potash fertilizer amount, positively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Youyan 599, but negatively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Sanbei 98. Stearic acid content was posi- tively correlated with sowing date, plant density, nitrogen fertilizer amount and phos- phate fertilizer amount. Linoleic acid was positively correlated with density and nitroge- nous fertilizer, but negatively correlated with potash fertilizer amount. Linolenic acid was positively correlated with nitrogen fertilizer amount and potash fertilizer amount. Eicosenoic acid was negatively correlated with sowing date. There were positive cor- relations and negative correlations among cultivation conditions and quality parame- ters, and the positive correlations and negative correlations could counteract each other. Expression of quality parameters for each treatment was the combined effect. Among the 50 pairs of simple correlations of five cultivation factors and ten quality parameters, 26 pairs were consistent between two varieties, 24 pairs of simple corre- lation were not. Sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount showed significant influence on erucic acid of two varieties, but small effect on palmitic acid. [Conclusion] The combined effect of the five cultivation factors could not fundamentally improve the quality traits of high grade hybrid rapeseed.展开更多
Cumulative effects on wetland soils under different cultivation patterns were analyzed in the experimental fields of the Ecological Experimental Station of Mire-wetlands in Sanjiang Plain. The results suggested that t...Cumulative effects on wetland soils under different cultivation patterns were analyzed in the experimental fields of the Ecological Experimental Station of Mire-wetlands in Sanjiang Plain. The results suggested that the paddy field combined with the glebe to act on the soil environment. Under the combination of natural and anthropological factors, the cultivation of the paddy field and the glebe obviously related with different kinds of fertility factors of soil. The remarkable relation among organic matter, total nitrogen and available nitrogen reflected the fertilization of the soil at some extent.展开更多
This paper mainly studies the effects of different propagation materials and cultivation years on the yield of Polygonatum odoratum under the forest.In this study,the cultivation experiment of P.odoratum was carried o...This paper mainly studies the effects of different propagation materials and cultivation years on the yield of Polygonatum odoratum under the forest.In this study,the cultivation experiment of P.odoratum was carried out by using the stem tip,stem body and seeds of P.odoratum as propagation materials.The yield of P.odoratum in different cultivation years with propagation by rhizome was also investigated.That is,the continuous growth of P.odoratum and the yield of P.odoratum each year after cultivation was statistically analyzed.The results showed that the germination rate under stem tip cultivation was fast,and the emergence time was also fast,which was more than 2 weeks earlier than that under stem body cultivation,and the seedling emergence rate reached 100%.The stem body was a new plant formed by sprouting from the buds of internodes,and the emergence rate was more than 95%.P.odoratum propagated by rhizome was harvested in the third or fourth year after cultivation,and the third year was the best harvest time.展开更多
In order to promote the transformation and high-quality development of strawberry industry and speed up the application of functional microbial products in strawberry,the application technology of functional microbial...In order to promote the transformation and high-quality development of strawberry industry and speed up the application of functional microbial products in strawberry,the application technology of functional microbial products in strawberry planting is studied and summarized.It mainly includes:the periods and methods of continuous cropping strawberry soil reduction and disinfection at high temperature,before and after strawberry planting,before plastic film mulching and whole process of plant spraying.Through multi-point test and demonstration,the purpose of advancing the season of strawberries,improving the quality,increasing production and increasing efficiency is achieved,and there is no risk of agricultural residue pollution,which meets the needs of people's consumption upgrading.Therefore,the application of functional microbial products in green ecological planting is very necessary,and it is worth further speeding up the demonstration and promotion.展开更多
Mathematics teaching is the foundation and focus of higher vocational education.However,there are still a series of problems in the mathematics education of higher vocational colleges in China,such as students’enthus...Mathematics teaching is the foundation and focus of higher vocational education.However,there are still a series of problems in the mathematics education of higher vocational colleges in China,such as students’enthusiasm for mathematics learning remain to be improved,and teachers still practice traditional teaching methods[1].In order to effectively improve this situation,it is necessary to reform the teaching of mathematics courses in higher vocational colleges,integrate the content of innovation quality cultivation,and implement scientific and reasonable teaching methods to achieve the effectiveness of mathematics teaching in higher vocational colleges.This paper mainly studies the effectiveness of cultivating innovative quality in the higher vocational mathematics teaching,with the hope to improve the overall quality of mathematics teaching.展开更多
This paper discussed the cost and benefit level of the marketing mix of organic vegetable cultivation. In 2011, the research assessed the effectiveness of policy of"Go Organic 2010" in Semarang municipality. The obj...This paper discussed the cost and benefit level of the marketing mix of organic vegetable cultivation. In 2011, the research assessed the effectiveness of policy of"Go Organic 2010" in Semarang municipality. The objectives of this work are to assess: (1] program implementations; (2) related stakeholders; C3] external and internal constrains; (4] the level of effectiveness; and (5) the efficiency on the use of production factors. Further, it aims to improve the competitiveness of the agricultural commodity through using efficient production factors, lessening the environmental damage as the use of pesticide, and promoting awareness of responsibilty among government, university, and society. Having employed interactive approach and SPSS 13.0 program, the result indicates that behavior of farming in the research area sounds to be less efficient. Further, agriculture extension agent performance in Semarang needs also to be better improved. Therefore, improvement on counselling activities is proposed to be a solution to make the performance of the extension optimum. Meanwhile, the number of extension agents is not sufficient. It is expected that the ideal number for extension--one village one extension--can be applied.展开更多
"Business English translation"is a specialized key course in higher vocational business English majors.The course objectives mainly enable the students to improve the business English translation competences..."Business English translation"is a specialized key course in higher vocational business English majors.The course objectives mainly enable the students to improve the business English translation competences.The thesis systemizes and concludes the effective cultivation of translation competence in higher vocational business English majors under the guidance of the subcompetences researches in the PACTE.展开更多
Hirschmanniella oryzae is one of the most im-portant pathogenic nematodes of rice. Thereare few data on the Integrated Pest Manage-ment (IPM) of H. oryzae except for somestudies on the chemical control of this nema-to...Hirschmanniella oryzae is one of the most im-portant pathogenic nematodes of rice. Thereare few data on the Integrated Pest Manage-ment (IPM) of H. oryzae except for somestudies on the chemical control of this nema-tode. A study on the IPM of H. oryzae wascarried out in Guangzhou from 1991 to 1995.展开更多
In China, the total annual production of cultured Laminaria japonica reached half million tons in dry weight there few years. The routine sporeling culture technique conducted in the greenhouse took at least three and...In China, the total annual production of cultured Laminaria japonica reached half million tons in dry weight there few years. The routine sporeling culture technique conducted in the greenhouse took at least three and half months. In such a case, sometimes the sporelings died within a few days due to destructive diseases. In Order to overcome the mentioned problems, a new sporeling culture technique, the clone technique, is developed. The method includes three stead: (1) Gametophyte clone culture. The spores and the gametophytes are cloned in flasks under favorable environments. (2) Sporeling cul ture. Male and female clones are crushed and spread onto a frame to allow the gametophytes to attach to the substrata. The frames are cultured in tanks, and the sporophytes reach 1 cm in length within one and a half months. (3) Outgrowing of the plant. The frames are put in the open sea when seawater temperature decreased to 20℃. After one month, the sporelings are large enough to be transplanted. It is concluded that the clone technique has the following advantages: (1)Large amount of clones can be produced in a short period of time. (2) Clone seeding method makes it free from the biological rhythm, one can seed the plant anytime all the year round. (3) It takes only one and a half months to complete the process of sporeling cultivation in the greenhouse. At present, this technique is used in the breeding of new strains of Laminaria.展开更多
The change in the quantity of cultivated land influences the structure, function and evolvement of ecosystem. The rational change in the quantity of cultivated land will be propitious to ecological security and sustai...The change in the quantity of cultivated land influences the structure, function and evolvement of ecosystem. The rational change in the quantity of cultivated land will be propitious to ecological security and sustainable development, and irrational change will deteriorate ecological environment. The concept of cultivated land quantity niche regulation was firstly put forward based on niche theory and the action-feedback mechanism between cultivated land quantity niche and cultivated land benefit niche. Then, the regulation measures of cultivated land quantity niche were brought forward in rural-urban area, agro-forest area and consolidation-reclamation-exploitation area. Finally, the ecological environmental effect after regulation was analyzed. The results show that different measures should be taken to regulate cultivated land quantity niche in different areas. The economic and social benefit niche of cultivated land should be promoted to regulate cultivated land quantity niche in rural-urban area and consolidation-reclamation-exploitation area. The social benefit niche of cultivated land should be reduced in agro-forest area. The regulation goal of cultivated land quantity niche will be attained by different measures.展开更多
Inspired by the phenomenon of heavy reduction in the area of cultivated land following the entry of Korea and Japan to the WTO,countries with a large population and inadequate amount of cultivated land similar to Chin...Inspired by the phenomenon of heavy reduction in the area of cultivated land following the entry of Korea and Japan to the WTO,countries with a large population and inadequate amount of cultivated land similar to China,this paper raises the problem of the potential effects on cultivated land in China following its entry to the WTO.The paper attempts analysis,using economic principles,of the effects of Chinese WTO membership on cultivated land from four aspects;tariff concessions,quota increment,comparative advantage,and the substitution principle.And the conclusion is mat China's entry to WTO may lead to a reduction in cultivated land.Finally,some countermeasures are proposed to resolve the problem.展开更多
Based on multi-type,multi-temporal remote sensing data,we have monitored recent changes in cultivated land use and vegetation,in sandy areas and salinized desertification in the Green Corridor zone of the main channel...Based on multi-type,multi-temporal remote sensing data,we have monitored recent changes in cultivated land use and vegetation,in sandy areas and salinized desertification in the Green Corridor zone of the main channel of the Tarim River Basin.The results of our investigation show that the ecological environment in the Green Corridor of the main channel of the Tarim River Basin has conspicuously improved from 2002 to 2004.These improvements show up largely in such aspects as an increase in the rate of vegetation cover,a reduction in desertification land areas and a weakening in the intensity of sandy and the salinized land.On the other hand,the cultivated area in the Tarim River Basin significantly increased from 2002 to 2004.The rate of growth in cultivated areas during this period was significantly higher than that from 1999 to 2002.The increase in the use of irrigation resulting from the substantial increase in cultivated areas has a long-term potential restraining effect on the restoration of ecological functions of the Tarim River.展开更多
A large areas of Larch seedlings, including container and bare-root seedlings (new and transplanted seedlings ) were inoculated pure inocula that were cultivated by using Suillus grevillei. Compared with those of cont...A large areas of Larch seedlings, including container and bare-root seedlings (new and transplanted seedlings ) were inoculated pure inocula that were cultivated by using Suillus grevillei. Compared with those of control area, all growth indices as rate of emergence, growth(in seedling height, collar diameter and number of lateral branch-root), rate of mycorrhiza inoculum, rate of survival and content of nutrient elements were greatly increased. Therefore, Suillus grevillei is a better and suitable mycorrhizal fungus to larch seedling either in the severe cold mountain area or in the plain region. It should be spread and used in larch cultivation and planting.展开更多
This paper focuses on a series of quantitative an al ysis models, such as grey relational analysis model, hierarchical cluster an alysis model, principal component analysis model, linear regression model and elastic c...This paper focuses on a series of quantitative an al ysis models, such as grey relational analysis model, hierarchical cluster an alysis model, principal component analysis model, linear regression model and elastic coefficient model. These models are used to analyze the comprehensive function and effect of driving forces systemically, including analysis on featur es, analysis for differentiating the primary and the secondary, analysis on comp rehensive effects, analysis of elasticity, analysis of prediction. The primary a nd characteristic factors can be extracted by analysis of features and analysis for differentiating the primary and the secondary. Analysis on prediction an d elasticity can predict the area of cultivated land in the future and find out which factors exert great influence on the cultivated land supply.展开更多
[Objective] The aim was to select a cultivation method suitable for sandy lands in Liaoning Province. [Method] The research explored effects of autumn plowing, autumn rotary cultivation, autumn ridging, and rotary cul...[Objective] The aim was to select a cultivation method suitable for sandy lands in Liaoning Province. [Method] The research explored effects of autumn plowing, autumn rotary cultivation, autumn ridging, and rotary cultivation before spring sowing on physical and chemical properties. [Result] By autumn plowing, surface soils were seriously eroded, more water was evaporated, and more nutrients lost; by autumn rotary cultivation, surface soils were seriously eroded also, reducing wa- ter content and nutrients; by autumn ridging, surface soils were slightly eroded, so that evaporation was light and fewer nutrients lost; by rotary cultivation before spring sowing, soil erosion was the lightest, with more water and nutrients maintained. [Conclusion] It is effective for improving anti-wind erosion by no-tillage during fallow period and land reclamation before sowing in semi-dry areas.展开更多
Nitric oxide(NO)emissions from alpine ecosystems conventionally being long-term cultivated with feed crops are not well quantified.The authors attempted to address this knowledge gap by performing a year-round experim...Nitric oxide(NO)emissions from alpine ecosystems conventionally being long-term cultivated with feed crops are not well quantified.The authors attempted to address this knowledge gap by performing a year-round experimental campaign in the northeastern Tibetan Plateau.Fertilized(F)and unfertilized(UF)treatments were established within a flat calcareous-soil site for the long-term cultivation of feed oats.NO fluxes and five soil variables were simultaneously measured.A single plow tillage accounted for approximately 54%–73%of the NO releases during the cropping period(CP);and the non-cropping period(NCP)contributed to 51%–58%of the annual emissions.The direct NO emissions factor(EFd)was 0.021%±0.021%.Significantly lower Q10 values(p<0.01)occurred in the F treatment during the CP(approximately 3.6)compared to those during the other period or in the other treatment(approximately 4.9?5.1),indicating a fertilizer-induced reduction in the temperature sensitivity.The selected soil variables jointly accounted for up to 72%(p<0.01)of the variance for all the fluxes across both treatments.This finding suggests that temporally and/or spatially distributed fluxes from alpine calcareous-soil ecosystems for feed crop production may be easily predicted if data on these soil variables are available.Further studies are needed to test the hypothesis that the EFd is larger in alpine feed-oat fields than those in this study if the soil moisture content is higher during the period following the basal application of ammoniumor urea-based fertilizer.展开更多
基金Supported by Major National Scientific and Technological Projects(2012BAD19B03,2012BAD04B12,201303017)Project of Innovation Center of Hubei Academy of Agricultural Sciences~~
文摘The occurrence rules of major diseases and pests in rice were investigated under six cultivation patterns, i.e., mechanical plowing-artificial transplanting, mechanical plowing-mechanical transplanting, mechanical plowing-scattered transplanting,cattle plowing-artificial transplanting, cattle plowing-mechanical transplanting and cattle plowing-scattered transplanting. The results showed that the six cultivation patterns showed small effects on the occurrence of rice sheath blight, second-generation rice planthopper, rice stem borer and rice false smut, but showed great effects on the occurrence of rice leaf folder, third-and fourth-generation rice planthopper and weeds; there were certain differences in the rice yield among different cultivation patterns, and the rice yield under the pattern of mechanical plowing-mechanical transplanting ranked first, while that under the pattern of cattle plowing-scattered transplanting ranked last.
基金Supported by Earmarked Fund for Modern Rapeseed Research System of China(nycytx-00563)High-oil Hybrid Brassica napus Rapeseed Cultivation Technology Research Program of Guizhou Academy of Agricultural Sciences [ZX (2007)015]+2 种基金New High-yield Rapeseed Cultivar Yoyan 599 Cultivation and Promotion Program of Agriculture department of Guizhou Province [(2009)007]Hybrid Rapeseed Culitivar Youyan 599 Promotion Test Program of Guizhou Academy of Agricultural Sciences[(2009)030]New High-oil Rapeseed Cultivar Sanbei 98 Cultivation and Promotion Program of Agriculture Department of Guizhou Province [(2010)3087]~~
文摘[Objective] This study aimed to investigate the combined effects of sowing date, plant density, nitrogenous fertilizer, phosphorus fertilizer and potassium fertilizer on quality parameters of high grade hybrid rapeseed. [Method] By using Youyan 599 and Sanbei 98 as experimental materials, quadratic orthogonal rotation combination with five factors was designed for this study. [Result] Erucic acid content was nega- tively correlated with sowing date and nitrogen fertilizer, positively correlated with plant density. Glucosinolate content was negatively correlated with sowing date, positively correlated with potash fertilizer amount. Oil content was negatively correlated with sowing date and nitrogen fertilizer amount, positively correlated with plant density and potash fertilizer amount. Protein content was positively correlated with sowing date and nitrogen fertilizer amount, negatively correlated with plant density and potash fer- tilizer amount. Oleic acid content was negatively correlated with phosphate fertilizer amount, positively correlated with nitrogen fertilizer amount. Palmitic acid was nega- tively correlated with potash fertilizer amount, positively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Youyan 599, but negatively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Sanbei 98. Stearic acid content was posi- tively correlated with sowing date, plant density, nitrogen fertilizer amount and phos- phate fertilizer amount. Linoleic acid was positively correlated with density and nitroge- nous fertilizer, but negatively correlated with potash fertilizer amount. Linolenic acid was positively correlated with nitrogen fertilizer amount and potash fertilizer amount. Eicosenoic acid was negatively correlated with sowing date. There were positive cor- relations and negative correlations among cultivation conditions and quality parame- ters, and the positive correlations and negative correlations could counteract each other. Expression of quality parameters for each treatment was the combined effect. Among the 50 pairs of simple correlations of five cultivation factors and ten quality parameters, 26 pairs were consistent between two varieties, 24 pairs of simple corre- lation were not. Sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount showed significant influence on erucic acid of two varieties, but small effect on palmitic acid. [Conclusion] The combined effect of the five cultivation factors could not fundamentally improve the quality traits of high grade hybrid rapeseed.
基金Supported by Chinese Youth Natural Sciences Fund Project(40501030)
文摘Cumulative effects on wetland soils under different cultivation patterns were analyzed in the experimental fields of the Ecological Experimental Station of Mire-wetlands in Sanjiang Plain. The results suggested that the paddy field combined with the glebe to act on the soil environment. Under the combination of natural and anthropological factors, the cultivation of the paddy field and the glebe obviously related with different kinds of fertility factors of soil. The remarkable relation among organic matter, total nitrogen and available nitrogen reflected the fertilization of the soil at some extent.
基金Special Project for Central Guidance in Local Science and Technology Development(ZY19C11)Special Project for the Investigation of Basic Resources of Science and Technology(2017FY101302-5)。
文摘This paper mainly studies the effects of different propagation materials and cultivation years on the yield of Polygonatum odoratum under the forest.In this study,the cultivation experiment of P.odoratum was carried out by using the stem tip,stem body and seeds of P.odoratum as propagation materials.The yield of P.odoratum in different cultivation years with propagation by rhizome was also investigated.That is,the continuous growth of P.odoratum and the yield of P.odoratum each year after cultivation was statistically analyzed.The results showed that the germination rate under stem tip cultivation was fast,and the emergence time was also fast,which was more than 2 weeks earlier than that under stem body cultivation,and the seedling emergence rate reached 100%.The stem body was a new plant formed by sprouting from the buds of internodes,and the emergence rate was more than 95%.P.odoratum propagated by rhizome was harvested in the third or fourth year after cultivation,and the third year was the best harvest time.
基金Supported by Zhenjiang Key R&D Program(NY2020017).
文摘In order to promote the transformation and high-quality development of strawberry industry and speed up the application of functional microbial products in strawberry,the application technology of functional microbial products in strawberry planting is studied and summarized.It mainly includes:the periods and methods of continuous cropping strawberry soil reduction and disinfection at high temperature,before and after strawberry planting,before plastic film mulching and whole process of plant spraying.Through multi-point test and demonstration,the purpose of advancing the season of strawberries,improving the quality,increasing production and increasing efficiency is achieved,and there is no risk of agricultural residue pollution,which meets the needs of people's consumption upgrading.Therefore,the application of functional microbial products in green ecological planting is very necessary,and it is worth further speeding up the demonstration and promotion.
文摘Mathematics teaching is the foundation and focus of higher vocational education.However,there are still a series of problems in the mathematics education of higher vocational colleges in China,such as students’enthusiasm for mathematics learning remain to be improved,and teachers still practice traditional teaching methods[1].In order to effectively improve this situation,it is necessary to reform the teaching of mathematics courses in higher vocational colleges,integrate the content of innovation quality cultivation,and implement scientific and reasonable teaching methods to achieve the effectiveness of mathematics teaching in higher vocational colleges.This paper mainly studies the effectiveness of cultivating innovative quality in the higher vocational mathematics teaching,with the hope to improve the overall quality of mathematics teaching.
文摘This paper discussed the cost and benefit level of the marketing mix of organic vegetable cultivation. In 2011, the research assessed the effectiveness of policy of"Go Organic 2010" in Semarang municipality. The objectives of this work are to assess: (1] program implementations; (2) related stakeholders; C3] external and internal constrains; (4] the level of effectiveness; and (5) the efficiency on the use of production factors. Further, it aims to improve the competitiveness of the agricultural commodity through using efficient production factors, lessening the environmental damage as the use of pesticide, and promoting awareness of responsibilty among government, university, and society. Having employed interactive approach and SPSS 13.0 program, the result indicates that behavior of farming in the research area sounds to be less efficient. Further, agriculture extension agent performance in Semarang needs also to be better improved. Therefore, improvement on counselling activities is proposed to be a solution to make the performance of the extension optimum. Meanwhile, the number of extension agents is not sufficient. It is expected that the ideal number for extension--one village one extension--can be applied.
文摘"Business English translation"is a specialized key course in higher vocational business English majors.The course objectives mainly enable the students to improve the business English translation competences.The thesis systemizes and concludes the effective cultivation of translation competence in higher vocational business English majors under the guidance of the subcompetences researches in the PACTE.
文摘Hirschmanniella oryzae is one of the most im-portant pathogenic nematodes of rice. Thereare few data on the Integrated Pest Manage-ment (IPM) of H. oryzae except for somestudies on the chemical control of this nema-tode. A study on the IPM of H. oryzae wascarried out in Guangzhou from 1991 to 1995.
基金Key Project, the Ninth Five-Year Plan of China! 96-008-01-02-06Project of Bio-Engineering Center of China! SSTC 96-C01-05-01
文摘In China, the total annual production of cultured Laminaria japonica reached half million tons in dry weight there few years. The routine sporeling culture technique conducted in the greenhouse took at least three and half months. In such a case, sometimes the sporelings died within a few days due to destructive diseases. In Order to overcome the mentioned problems, a new sporeling culture technique, the clone technique, is developed. The method includes three stead: (1) Gametophyte clone culture. The spores and the gametophytes are cloned in flasks under favorable environments. (2) Sporeling cul ture. Male and female clones are crushed and spread onto a frame to allow the gametophytes to attach to the substrata. The frames are cultured in tanks, and the sporophytes reach 1 cm in length within one and a half months. (3) Outgrowing of the plant. The frames are put in the open sea when seawater temperature decreased to 20℃. After one month, the sporelings are large enough to be transplanted. It is concluded that the clone technique has the following advantages: (1)Large amount of clones can be produced in a short period of time. (2) Clone seeding method makes it free from the biological rhythm, one can seed the plant anytime all the year round. (3) It takes only one and a half months to complete the process of sporeling cultivation in the greenhouse. At present, this technique is used in the breeding of new strains of Laminaria.
基金Project(2006BAJ05A14-2)supported by the National Science and Technology Supporting Program of ChinaProject(11YJC790139)supported by the Humanities and Social Sciences Program of Ministry of Education of ChinaProject(2011GGJS-053)supported by the Foundation for University Young Key Teacher by Henan Province of China
文摘The change in the quantity of cultivated land influences the structure, function and evolvement of ecosystem. The rational change in the quantity of cultivated land will be propitious to ecological security and sustainable development, and irrational change will deteriorate ecological environment. The concept of cultivated land quantity niche regulation was firstly put forward based on niche theory and the action-feedback mechanism between cultivated land quantity niche and cultivated land benefit niche. Then, the regulation measures of cultivated land quantity niche were brought forward in rural-urban area, agro-forest area and consolidation-reclamation-exploitation area. Finally, the ecological environmental effect after regulation was analyzed. The results show that different measures should be taken to regulate cultivated land quantity niche in different areas. The economic and social benefit niche of cultivated land should be promoted to regulate cultivated land quantity niche in rural-urban area and consolidation-reclamation-exploitation area. The social benefit niche of cultivated land should be reduced in agro-forest area. The regulation goal of cultivated land quantity niche will be attained by different measures.
基金supported by the National Natural Science Foundation of China[grant number 71233004]and[grant number 71003052]
文摘Inspired by the phenomenon of heavy reduction in the area of cultivated land following the entry of Korea and Japan to the WTO,countries with a large population and inadequate amount of cultivated land similar to China,this paper raises the problem of the potential effects on cultivated land in China following its entry to the WTO.The paper attempts analysis,using economic principles,of the effects of Chinese WTO membership on cultivated land from four aspects;tariff concessions,quota increment,comparative advantage,and the substitution principle.And the conclusion is mat China's entry to WTO may lead to a reduction in cultivated land.Finally,some countermeasures are proposed to resolve the problem.
基金Financial support for this work was provided by the National Natural Science Foundation of China (No. 41040011)the Fun-damental Research Funds for the Central Universities (No.CHD2010JC103)
文摘Based on multi-type,multi-temporal remote sensing data,we have monitored recent changes in cultivated land use and vegetation,in sandy areas and salinized desertification in the Green Corridor zone of the main channel of the Tarim River Basin.The results of our investigation show that the ecological environment in the Green Corridor of the main channel of the Tarim River Basin has conspicuously improved from 2002 to 2004.These improvements show up largely in such aspects as an increase in the rate of vegetation cover,a reduction in desertification land areas and a weakening in the intensity of sandy and the salinized land.On the other hand,the cultivated area in the Tarim River Basin significantly increased from 2002 to 2004.The rate of growth in cultivated areas during this period was significantly higher than that from 1999 to 2002.The increase in the use of irrigation resulting from the substantial increase in cultivated areas has a long-term potential restraining effect on the restoration of ecological functions of the Tarim River.
文摘A large areas of Larch seedlings, including container and bare-root seedlings (new and transplanted seedlings ) were inoculated pure inocula that were cultivated by using Suillus grevillei. Compared with those of control area, all growth indices as rate of emergence, growth(in seedling height, collar diameter and number of lateral branch-root), rate of mycorrhiza inoculum, rate of survival and content of nutrient elements were greatly increased. Therefore, Suillus grevillei is a better and suitable mycorrhizal fungus to larch seedling either in the severe cold mountain area or in the plain region. It should be spread and used in larch cultivation and planting.
文摘This paper focuses on a series of quantitative an al ysis models, such as grey relational analysis model, hierarchical cluster an alysis model, principal component analysis model, linear regression model and elastic coefficient model. These models are used to analyze the comprehensive function and effect of driving forces systemically, including analysis on featur es, analysis for differentiating the primary and the secondary, analysis on comp rehensive effects, analysis of elasticity, analysis of prediction. The primary a nd characteristic factors can be extracted by analysis of features and analysis for differentiating the primary and the secondary. Analysis on prediction an d elasticity can predict the area of cultivated land in the future and find out which factors exert great influence on the cultivated land supply.
文摘[Objective] The aim was to select a cultivation method suitable for sandy lands in Liaoning Province. [Method] The research explored effects of autumn plowing, autumn rotary cultivation, autumn ridging, and rotary cultivation before spring sowing on physical and chemical properties. [Result] By autumn plowing, surface soils were seriously eroded, more water was evaporated, and more nutrients lost; by autumn rotary cultivation, surface soils were seriously eroded also, reducing wa- ter content and nutrients; by autumn ridging, surface soils were slightly eroded, so that evaporation was light and fewer nutrients lost; by rotary cultivation before spring sowing, soil erosion was the lightest, with more water and nutrients maintained. [Conclusion] It is effective for improving anti-wind erosion by no-tillage during fallow period and land reclamation before sowing in semi-dry areas.
基金jointly financed by the Ministry of Science and Technology of China(Grant No.2016YFA0602303)the National Natural Science Foundation of China(Grant Nos.41775141,41375152,and 41603075)
文摘Nitric oxide(NO)emissions from alpine ecosystems conventionally being long-term cultivated with feed crops are not well quantified.The authors attempted to address this knowledge gap by performing a year-round experimental campaign in the northeastern Tibetan Plateau.Fertilized(F)and unfertilized(UF)treatments were established within a flat calcareous-soil site for the long-term cultivation of feed oats.NO fluxes and five soil variables were simultaneously measured.A single plow tillage accounted for approximately 54%–73%of the NO releases during the cropping period(CP);and the non-cropping period(NCP)contributed to 51%–58%of the annual emissions.The direct NO emissions factor(EFd)was 0.021%±0.021%.Significantly lower Q10 values(p<0.01)occurred in the F treatment during the CP(approximately 3.6)compared to those during the other period or in the other treatment(approximately 4.9?5.1),indicating a fertilizer-induced reduction in the temperature sensitivity.The selected soil variables jointly accounted for up to 72%(p<0.01)of the variance for all the fluxes across both treatments.This finding suggests that temporally and/or spatially distributed fluxes from alpine calcareous-soil ecosystems for feed crop production may be easily predicted if data on these soil variables are available.Further studies are needed to test the hypothesis that the EFd is larger in alpine feed-oat fields than those in this study if the soil moisture content is higher during the period following the basal application of ammoniumor urea-based fertilizer.