New research and development(R&D)institutions are an important part of the national innovation system,playing an important role in promoting the transformation of scientific and technological achievements.In recen...New research and development(R&D)institutions are an important part of the national innovation system,playing an important role in promoting the transformation of scientific and technological achievements.In recent years,new R&D institutions have gradually become the driving force of innovation-driven development in China.Taking new R&D institutions in Zhejiang Province as the research object,this paper studies the internal talent training path and performance evaluation mechanism of new R&D institutions in Zhejiang Province by using the literature research method,comparison method,case verification method,and other methods.The investigation results show that there are problems such as lack of material and spiritual support and neglect of the absorption of local talents in the internal talent training,and there are problems such as unclear standards,insufficient data,and opaque processes in the performance evaluation mechanism,which greatly affect the establishment and improvement of the performance evaluation mechanism.Given the above problems,this paper puts forward a forward-looking,oriented,flexible,and compatible talent training path and performance evaluation mechanism,hoping to optimize the effective internal talent training path of new R&D institutions,improve the evaluation performance,and promote healthy development of new R&D institutions in Zhejiang Province.展开更多
Cultivated land transition and its driving mechanism are the hotspots among studies on land use change. In this study, we constructed a framework to study the driving mechanism of cultivated land transition from the q...Cultivated land transition and its driving mechanism are the hotspots among studies on land use change. In this study, we constructed a framework to study the driving mechanism of cultivated land transition from the quantitative perspective. Based on the vector data of land use in 1990, 2000 and 2009 of Yantai Proper, Shandong Province China, 11 explanatory variables were chosen from two aspects: the elevation, slope, cost distance to major water area and cost distance to minor water area, which presented physical factors; cost distance to district center, cost distance to town center, cost distance to city expansion center, cost distance to major roads, cost distance to city roads, cost distance to county roads and cost distance to rural roads, which presented the socio-economic factors. Combined with spatial analysis tools and Logistic regression analysis model, we construct Logistic regression analyses with four objectives that were urban construction land, rural residential land, orchard and other lands. The results show that, cost distance to district center, cost distance to town center, cost distance to city expansion center and cost distance to city roads are the significant explanatory variables for the transition of cultivated land into urban construction land. The main explained factors on the transition of cultivated land into rural residential land are slope, cost distance to town center, cost distance to county roads and cost distance to rural roads. Slope, cost distance to minor water area, cost distance to town center, cost distance to county roads and cost distance to rural roads are the significant explanatory variables for the transition of cultivated land into orchard land. Elevation, slope, cost distance to major water area and cost distance to minor water area are the main explanatory variables on the transition of cultivated land into other land uses.展开更多
In order to reveal the differences between different peony varieties and facilities,thousands of tissue culture seedlings of 21 Itoh peony varieties imported from abroad were used as test materials,and the peony domes...In order to reveal the differences between different peony varieties and facilities,thousands of tissue culture seedlings of 21 Itoh peony varieties imported from abroad were used as test materials,and the peony domestication cultivation method used in the past was used as a control. The technical measures and mechanisms for the outdoor domestication of seedlings and the survival of field transplantation were studied. The results indicate that the main factors and measures for effectively protecting the outdoor transplanting of tissue culture seedlings include cultivating sound and strong seedlings,transplanting in proper period of spring,and providing good ventilating places and facilities,removing leaves,keeping buds and releasing dormancy before transplantation,planting depth should meet the requirement of exposing to the root neck,changing the pots according to the size of seedlings,the substrate should be loose and permeable,seriously disinfected and sterilized,scientific management,and prevention and control of diseases and insect pests. In addition,the survival mechanism was also analyzed,and the reasons and countermeasures for the successful application of peony tissue culture in China were found. Finally,the differences in survival rates between different varieties and facilities were summarized.展开更多
The new bulk purple yam variety Suyu 2,which had high quality,efficiency and was suitable for production in a highly mechanized cultivation,was bred by special and was suitable for whole-course mechanized cultivation....The new bulk purple yam variety Suyu 2,which had high quality,efficiency and was suitable for production in a highly mechanized cultivation,was bred by special and was suitable for whole-course mechanized cultivation.Integrated with agricultural machinery and agricultural trait,four kinds of machines produced by two factories from Jiangsu and Shandong could complete 10 kinds of main production processes,including rotary tillage,ridging,sowing,intertillage,topdressing,drug delivery,weeding,hilling,vine cutting and harvest.The work efficiency of single machine was 4-5 hm^2/d,and the production pattern got the cost saving and effectiveness increasing in the main yam producing area.The benefit reached over RMB 37500 yuan/hm^2 in special vegetable area.It was simple,feasible and easy to popularize the mechanization cultivation technique.展开更多
Firstly, the background, ways, countermeasures, problems and realistic significance of cultivating new professional farmers in China were studied, and then the mechanism for cultivating new professional farmers was di...Firstly, the background, ways, countermeasures, problems and realistic significance of cultivating new professional farmers in China were studied, and then the mechanism for cultivating new professional farmers was discussed based on Town S. The results show that cultivating new professional farmers can fundamentally relieve "three rural issues" existing for a long time and is of great significance to rural economic development. For instance, it can integrate rural human capital and release modern productivity, increase farmers' income and improve rural economy, increase land utilization and output per unit area, and break through the bottlenecks during agricultural development to realize agricultural modernization. According to the case study of Town S, during the process of cultivating new professional farmers, governments at all levels ought to adopt many effective measures and strengthen support to realize cultivation targets planed early.展开更多
Firstly, based on significance of developing agricultural mechanization and automation and current situations of agricultural mechanization and automation specialities in colleges and universities, we put forward obje...Firstly, based on significance of developing agricultural mechanization and automation and current situations of agricultural mechanization and automation specialities in colleges and universities, we put forward objectives of personnel cultivation for agricultural mechanization and automation specialities. Then, we analyze the exploration and practice of personnel cultivation for agricultural mechanization and automation specialities from four aspects, including course system setting, teaching materials construction, laboratory construction, and construction of practical teaching link. Finally, it is expected to provide references for running schools and cultivating excellent professional personnel.展开更多
In past 30 years, the wheat yield per unit area of China has increased by 79%. The super-high-yield(SH) cultivation played an important role in improving the wheat photosynthesis and yield. In order to find the ecophy...In past 30 years, the wheat yield per unit area of China has increased by 79%. The super-high-yield(SH) cultivation played an important role in improving the wheat photosynthesis and yield. In order to find the ecophysiological mechanism underneath the high photosynthesis of SH cultivation, in situ diurnal changes in the photosynthetic gas exchange and chlorophyll(Chl) a fluorescence of field-grown wheat plants during the grain-filling stage and environmental factors were investigated. During the late grain-filling stage at 24 days after anthesis(DAA), the diurnal changes in net CO_(2) assimilation rate were higher under SH treatment than under high-yield(H) treatment. From 8 to 24 DAA, the actual quantum yield of photosystem II(PSII) electron transport in the light-adapted state(ΦPSII) in the flag leaves at noon under SH treatment were significantly higher than those under H treatment. The leaf temperature, soil temperature and soil moisture were better suited for higher rates of leaf photosynthesis under SH treatment than those under H treatment at noon. Such diurnal changes in environmental factors in wheat fields could be one of the mechanisms for the higher biomass and yield under SH cultivation than those under H cultivation. ΦPSII and CO_(2) exchange rate in wheat flag leaves under SH and H treatments had a linear correlation which could provide new insight to evaluate the wheat photosynthesis performance under different conditions.展开更多
Optimized high-yielding cultivation is of great significance to ensure stable and high yield of rice in China. This paper reviewed several super high-yielding cultivation modes, analyzed the effects of different culti...Optimized high-yielding cultivation is of great significance to ensure stable and high yield of rice in China. This paper reviewed several super high-yielding cultivation modes, analyzed the effects of different cultivation modes on rice agronomic traits and physiological characteristics, and discussed the advances in rice mechanized cultivation and mode. Finally, the future development prospects of rice cultivation were put forward.展开更多
It is well known that quackgrass is both very aggressive and persistent. In agriculture, many attempts have been made to eliminate this weed without success. Within the context of a sustainable agriculture, mechanical...It is well known that quackgrass is both very aggressive and persistent. In agriculture, many attempts have been made to eliminate this weed without success. Within the context of a sustainable agriculture, mechanical control of quackgrass represents an interesting alternative to chemical means. The use of a "C" shaped mounted tine cultivator, a rotary cross-harrow, and an "S" shaped trailed tine cultivator (alone or in combination) to control quackgrass in grassland was investigated. The rate of quackgrass present in each experimental plot was determined before and after the treatments using a one square meter quadrant. Also, the time required for each passage as well as the fuel consumption were computed. Results revealed that the fuel consumption and the time required by the "C" and "S" shaped tine cultivators to transport and expose the rhizomes to the sun on the soil surface highly depend on the quality of tillage during the first stubble passage. Also, subsequent tillage with the "C" shaped tine cultivator after a first passage with a rotary cross-harrow resulted in less fuel consumption and passage time. On the other hand, stubble and subsequent soil tillage with only the "C" shaped tine cultivator is the least successful method.展开更多
This study, carried out in a sugarcane mill located in the center-west region of Sao Paulo state, Brazil, aimed to evaluate the association of sucrose amount (POL%) with sugarcane varieties and cutting stages using ...This study, carried out in a sugarcane mill located in the center-west region of Sao Paulo state, Brazil, aimed to evaluate the association of sucrose amount (POL%) with sugarcane varieties and cutting stages using mechanized harvesting. A two-way analysis of variance (ANOVA), complemented by multiple comparison tests, was used in order to identify the effects of variety types and cutting stages on the sugarcane POL% content. An interaction between the sugarcane variety and the cutting stage was observed; therefore, both two factors cannot be independently evaluated regarding POL%. In addition, it was found that the sucrose amount from the plant production in the evaluated period presented significant differences between the cutting stages only for one variety, namely CTC2, which was different from the others in most of the cutting stages. Considering the observed results, it can be concluded that analyzing sucrose amount statistically in the mill production can allow producers to posteriorly better monitor information on the sugarcane varieties harvested under mechanized processes.展开更多
According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quali...According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quality of cultivated land in Zhengzhou City. The results show that(1) the quality of cultivated land in Zhengzhou City has slightly increased during the study period. Due to the decrease in the amount of cultivated land,the production capacity has declined.(2) The impact of different types of cultivated land change on the quality of regional cultivated land is in the order of gradual change> decrease > increase > land construction project.(3) Zhengzhou City is able to maintain the quality of regional cultivated land through new cultivated land and project construction,but fails to maintain the production capacity. By analyzing the mechanism of regional cultivated land quality change in different types,the relationship between quality changes in various types of areas and overall quality changes could be analyzed,and it could provide policy recommendations for managers to formulate farmland quality and capacity protection,with significant application value.展开更多
With Guiteyou 2 as the test mulberry variety, mulberry herbaceous cultivation field was established at the planting densities of 60 000,90 000 and 120 000 plants/hm2, respectively. Hybrid mulberry herbaceous cultivati...With Guiteyou 2 as the test mulberry variety, mulberry herbaceous cultivation field was established at the planting densities of 60 000,90 000 and 120 000 plants/hm2, respectively. Hybrid mulberry herbaceous cultivation test was conducted, with Tongxiangqing mulberry field of mid-fist-form at conventional planting density of 4 995 plants/hm2 as the control. The results showed that the leaf yield of herbaceous cultivation mulberry was closely related to the planting density. With the increasing planting density, the leaf yield per plant was decreasing, but the leaf yield per unit area of mulberry field was increasing. The annual leaf yield per unit area in the mulberry field with the average planting density of 120 000 plants/hm2 was 37 560 kg/hm2, 2.14 times of that of the control field. The moisture content of mulberry leaf in herbaceous cultivation field was 4.74% higher than the control; the contents of crude protein, crude fat, crude fiber and crude ash were 1.264%, 0.014%, 0.744% and 0.002%lower than the control, respectively. Comparison of leaf rearing with herbaceous cultivation mulberry and control mulberry showed that there was no significant difference in growth status of silkworm. The cocoon weight, cocoon shell weight, cocoon yield per 10 000 larvae, cocoon filament length and non-broken filament length of Chuanshan × Shushui were 12.81%, 14.29%, 13.85%, 5.95% and 7.68% lower than the control, respectively; but the percentage of common cocoons was 0.16% higher than the control; the cleanness and neatness were 0.2 and 1.25 points higher than the control;the filament size was 0.196 dtex lower than the control. The cocoon weight, cocoon shell weight, cocoon yield per 10 000 larvae, cocoon filament length and non-broken filament length of Jingsong × Haoyue were 11.06%, 10.20%, 11.53%, 9.46% and 9.03% lower than the control, respectively;but the percentage of common cocoons was 1.77% higher than the control; the cleanness and neatness were 0.12 and 2.50 points higher the control;and the filament size was 0.196 dtex lower than the control.展开更多
According to the statistics of cultivated land in Yantai area during the Reform and Opening-up over the past 20 years and with the detailed survey and changing data of land use during the recent live years, this paper...According to the statistics of cultivated land in Yantai area during the Reform and Opening-up over the past 20 years and with the detailed survey and changing data of land use during the recent live years, this paper reveals the basic characteristics of the resource utilization, the basic process of the changes, regional differences, and current direction of cultivated land In addition, this paper makes a preliminary research on the major driving factors and the influence mechanism for the changes in the cultivated land area. and reaches the following conclasions: (1) There was a trend of obvious fluctuant decrease in cultivated laud area during the past 20 years. The changes of cultivated land have undergone the process - slow decrease,steep decrease, slow decrease. And there were three peak periods of cultivated land loss around 1985. 1987-1996 and 1991-1993 respectively (2) The decreased cultivated land was mainly converted into land for industry and mining, residential area. and all kinds of traffic and orchards. The increase of cultivated land mainly came from exploitation and land and arrangement and reclamation of industry and mining land (3) The economic development. population growth and policy are the dominant macro-driving factors for the decrease of cultivated land area in Yantai. The obvious sudden changes during the change process of cultivated land acreage are relevant to the national macro.policies background The rapid decrease of cnltivated land area is synchronous with the overheated economic growth resulting from the direct investment in fixed assets. Spatial distribution of the decrease in cultivated land is congruous with the differences in speed and the scale of economic growth between the different regions of Yantai area. Furthermore. the decrease in cultivated land caused by population increase cannot be ignored.展开更多
文摘New research and development(R&D)institutions are an important part of the national innovation system,playing an important role in promoting the transformation of scientific and technological achievements.In recent years,new R&D institutions have gradually become the driving force of innovation-driven development in China.Taking new R&D institutions in Zhejiang Province as the research object,this paper studies the internal talent training path and performance evaluation mechanism of new R&D institutions in Zhejiang Province by using the literature research method,comparison method,case verification method,and other methods.The investigation results show that there are problems such as lack of material and spiritual support and neglect of the absorption of local talents in the internal talent training,and there are problems such as unclear standards,insufficient data,and opaque processes in the performance evaluation mechanism,which greatly affect the establishment and improvement of the performance evaluation mechanism.Given the above problems,this paper puts forward a forward-looking,oriented,flexible,and compatible talent training path and performance evaluation mechanism,hoping to optimize the effective internal talent training path of new R&D institutions,improve the evaluation performance,and promote healthy development of new R&D institutions in Zhejiang Province.
基金Under the auspices of National Natural Science Foundation of China(No.41130748)
文摘Cultivated land transition and its driving mechanism are the hotspots among studies on land use change. In this study, we constructed a framework to study the driving mechanism of cultivated land transition from the quantitative perspective. Based on the vector data of land use in 1990, 2000 and 2009 of Yantai Proper, Shandong Province China, 11 explanatory variables were chosen from two aspects: the elevation, slope, cost distance to major water area and cost distance to minor water area, which presented physical factors; cost distance to district center, cost distance to town center, cost distance to city expansion center, cost distance to major roads, cost distance to city roads, cost distance to county roads and cost distance to rural roads, which presented the socio-economic factors. Combined with spatial analysis tools and Logistic regression analysis model, we construct Logistic regression analyses with four objectives that were urban construction land, rural residential land, orchard and other lands. The results show that, cost distance to district center, cost distance to town center, cost distance to city expansion center and cost distance to city roads are the significant explanatory variables for the transition of cultivated land into urban construction land. The main explained factors on the transition of cultivated land into rural residential land are slope, cost distance to town center, cost distance to county roads and cost distance to rural roads. Slope, cost distance to minor water area, cost distance to town center, cost distance to county roads and cost distance to rural roads are the significant explanatory variables for the transition of cultivated land into orchard land. Elevation, slope, cost distance to major water area and cost distance to minor water area are the main explanatory variables on the transition of cultivated land into other land uses.
文摘In order to reveal the differences between different peony varieties and facilities,thousands of tissue culture seedlings of 21 Itoh peony varieties imported from abroad were used as test materials,and the peony domestication cultivation method used in the past was used as a control. The technical measures and mechanisms for the outdoor domestication of seedlings and the survival of field transplantation were studied. The results indicate that the main factors and measures for effectively protecting the outdoor transplanting of tissue culture seedlings include cultivating sound and strong seedlings,transplanting in proper period of spring,and providing good ventilating places and facilities,removing leaves,keeping buds and releasing dormancy before transplantation,planting depth should meet the requirement of exposing to the root neck,changing the pots according to the size of seedlings,the substrate should be loose and permeable,seriously disinfected and sterilized,scientific management,and prevention and control of diseases and insect pests. In addition,the survival mechanism was also analyzed,and the reasons and countermeasures for the successful application of peony tissue culture in China were found. Finally,the differences in survival rates between different varieties and facilities were summarized.
文摘The new bulk purple yam variety Suyu 2,which had high quality,efficiency and was suitable for production in a highly mechanized cultivation,was bred by special and was suitable for whole-course mechanized cultivation.Integrated with agricultural machinery and agricultural trait,four kinds of machines produced by two factories from Jiangsu and Shandong could complete 10 kinds of main production processes,including rotary tillage,ridging,sowing,intertillage,topdressing,drug delivery,weeding,hilling,vine cutting and harvest.The work efficiency of single machine was 4-5 hm^2/d,and the production pattern got the cost saving and effectiveness increasing in the main yam producing area.The benefit reached over RMB 37500 yuan/hm^2 in special vegetable area.It was simple,feasible and easy to popularize the mechanization cultivation technique.
基金Supported by National Social Science Foundation of China (11CSH010)Humanities and Social Sciences Foundation of Jiangxi Higher Education (ZZ1210)
文摘Firstly, the background, ways, countermeasures, problems and realistic significance of cultivating new professional farmers in China were studied, and then the mechanism for cultivating new professional farmers was discussed based on Town S. The results show that cultivating new professional farmers can fundamentally relieve "three rural issues" existing for a long time and is of great significance to rural economic development. For instance, it can integrate rural human capital and release modern productivity, increase farmers' income and improve rural economy, increase land utilization and output per unit area, and break through the bottlenecks during agricultural development to realize agricultural modernization. According to the case study of Town S, during the process of cultivating new professional farmers, governments at all levels ought to adopt many effective measures and strengthen support to realize cultivation targets planed early.
基金Supported by the Operating Expenses of Basic Research of Jiling University (200810001)
文摘Firstly, based on significance of developing agricultural mechanization and automation and current situations of agricultural mechanization and automation specialities in colleges and universities, we put forward objectives of personnel cultivation for agricultural mechanization and automation specialities. Then, we analyze the exploration and practice of personnel cultivation for agricultural mechanization and automation specialities from four aspects, including course system setting, teaching materials construction, laboratory construction, and construction of practical teaching link. Finally, it is expected to provide references for running schools and cultivating excellent professional personnel.
基金supported by the National Key Research and Development Program of China(2016YFD0300102 and 2016YFD0300105)the Key Research and Development Plan in Shaanxi Province,China(2019NY-054)the“Western Light”Visiting Scholarship Program,China。
文摘In past 30 years, the wheat yield per unit area of China has increased by 79%. The super-high-yield(SH) cultivation played an important role in improving the wheat photosynthesis and yield. In order to find the ecophysiological mechanism underneath the high photosynthesis of SH cultivation, in situ diurnal changes in the photosynthetic gas exchange and chlorophyll(Chl) a fluorescence of field-grown wheat plants during the grain-filling stage and environmental factors were investigated. During the late grain-filling stage at 24 days after anthesis(DAA), the diurnal changes in net CO_(2) assimilation rate were higher under SH treatment than under high-yield(H) treatment. From 8 to 24 DAA, the actual quantum yield of photosystem II(PSII) electron transport in the light-adapted state(ΦPSII) in the flag leaves at noon under SH treatment were significantly higher than those under H treatment. The leaf temperature, soil temperature and soil moisture were better suited for higher rates of leaf photosynthesis under SH treatment than those under H treatment at noon. Such diurnal changes in environmental factors in wheat fields could be one of the mechanisms for the higher biomass and yield under SH cultivation than those under H cultivation. ΦPSII and CO_(2) exchange rate in wheat flag leaves under SH and H treatments had a linear correlation which could provide new insight to evaluate the wheat photosynthesis performance under different conditions.
基金Supported by Key Laboratory of Pesticide Harmless Application of Hunan ProvinceScience and Technology Plan Project of Loudi City(201601)
文摘Optimized high-yielding cultivation is of great significance to ensure stable and high yield of rice in China. This paper reviewed several super high-yielding cultivation modes, analyzed the effects of different cultivation modes on rice agronomic traits and physiological characteristics, and discussed the advances in rice mechanized cultivation and mode. Finally, the future development prospects of rice cultivation were put forward.
文摘It is well known that quackgrass is both very aggressive and persistent. In agriculture, many attempts have been made to eliminate this weed without success. Within the context of a sustainable agriculture, mechanical control of quackgrass represents an interesting alternative to chemical means. The use of a "C" shaped mounted tine cultivator, a rotary cross-harrow, and an "S" shaped trailed tine cultivator (alone or in combination) to control quackgrass in grassland was investigated. The rate of quackgrass present in each experimental plot was determined before and after the treatments using a one square meter quadrant. Also, the time required for each passage as well as the fuel consumption were computed. Results revealed that the fuel consumption and the time required by the "C" and "S" shaped tine cultivators to transport and expose the rhizomes to the sun on the soil surface highly depend on the quality of tillage during the first stubble passage. Also, subsequent tillage with the "C" shaped tine cultivator after a first passage with a rotary cross-harrow resulted in less fuel consumption and passage time. On the other hand, stubble and subsequent soil tillage with only the "C" shaped tine cultivator is the least successful method.
文摘This study, carried out in a sugarcane mill located in the center-west region of Sao Paulo state, Brazil, aimed to evaluate the association of sucrose amount (POL%) with sugarcane varieties and cutting stages using mechanized harvesting. A two-way analysis of variance (ANOVA), complemented by multiple comparison tests, was used in order to identify the effects of variety types and cutting stages on the sugarcane POL% content. An interaction between the sugarcane variety and the cutting stage was observed; therefore, both two factors cannot be independently evaluated regarding POL%. In addition, it was found that the sucrose amount from the plant production in the evaluated period presented significant differences between the cutting stages only for one variety, namely CTC2, which was different from the others in most of the cutting stages. Considering the observed results, it can be concluded that analyzing sucrose amount statistically in the mill production can allow producers to posteriorly better monitor information on the sugarcane varieties harvested under mechanized processes.
基金Supported by Basic Scientific Research Project of Henan Academy of Sciences(200601078)Henan Youth Science(212300410168)Henan Science and Technology Plan Project (212400410263)。
文摘According to the reason of quality change,cultivated land is divided into four change types: decrease,increase,land construction project and gradual change. Farmland grading factor method is used to evaluate the quality of cultivated land in Zhengzhou City. The results show that(1) the quality of cultivated land in Zhengzhou City has slightly increased during the study period. Due to the decrease in the amount of cultivated land,the production capacity has declined.(2) The impact of different types of cultivated land change on the quality of regional cultivated land is in the order of gradual change> decrease > increase > land construction project.(3) Zhengzhou City is able to maintain the quality of regional cultivated land through new cultivated land and project construction,but fails to maintain the production capacity. By analyzing the mechanism of regional cultivated land quality change in different types,the relationship between quality changes in various types of areas and overall quality changes could be analyzed,and it could provide policy recommendations for managers to formulate farmland quality and capacity protection,with significant application value.
基金Supported by Technology Research and Development Program of Nanchong,2015(No.15A0053)
文摘With Guiteyou 2 as the test mulberry variety, mulberry herbaceous cultivation field was established at the planting densities of 60 000,90 000 and 120 000 plants/hm2, respectively. Hybrid mulberry herbaceous cultivation test was conducted, with Tongxiangqing mulberry field of mid-fist-form at conventional planting density of 4 995 plants/hm2 as the control. The results showed that the leaf yield of herbaceous cultivation mulberry was closely related to the planting density. With the increasing planting density, the leaf yield per plant was decreasing, but the leaf yield per unit area of mulberry field was increasing. The annual leaf yield per unit area in the mulberry field with the average planting density of 120 000 plants/hm2 was 37 560 kg/hm2, 2.14 times of that of the control field. The moisture content of mulberry leaf in herbaceous cultivation field was 4.74% higher than the control; the contents of crude protein, crude fat, crude fiber and crude ash were 1.264%, 0.014%, 0.744% and 0.002%lower than the control, respectively. Comparison of leaf rearing with herbaceous cultivation mulberry and control mulberry showed that there was no significant difference in growth status of silkworm. The cocoon weight, cocoon shell weight, cocoon yield per 10 000 larvae, cocoon filament length and non-broken filament length of Chuanshan × Shushui were 12.81%, 14.29%, 13.85%, 5.95% and 7.68% lower than the control, respectively; but the percentage of common cocoons was 0.16% higher than the control; the cleanness and neatness were 0.2 and 1.25 points higher than the control;the filament size was 0.196 dtex lower than the control. The cocoon weight, cocoon shell weight, cocoon yield per 10 000 larvae, cocoon filament length and non-broken filament length of Jingsong × Haoyue were 11.06%, 10.20%, 11.53%, 9.46% and 9.03% lower than the control, respectively;but the percentage of common cocoons was 1.77% higher than the control; the cleanness and neatness were 0.12 and 2.50 points higher the control;and the filament size was 0.196 dtex lower than the control.
基金Supported by National Natural Science Foundation of China (40101005), Natural Science Foundation of Shandong Province (Q2002E03), and Education Department Foundation of ShandongProvince (J02L01).
文摘According to the statistics of cultivated land in Yantai area during the Reform and Opening-up over the past 20 years and with the detailed survey and changing data of land use during the recent live years, this paper reveals the basic characteristics of the resource utilization, the basic process of the changes, regional differences, and current direction of cultivated land In addition, this paper makes a preliminary research on the major driving factors and the influence mechanism for the changes in the cultivated land area. and reaches the following conclasions: (1) There was a trend of obvious fluctuant decrease in cultivated laud area during the past 20 years. The changes of cultivated land have undergone the process - slow decrease,steep decrease, slow decrease. And there were three peak periods of cultivated land loss around 1985. 1987-1996 and 1991-1993 respectively (2) The decreased cultivated land was mainly converted into land for industry and mining, residential area. and all kinds of traffic and orchards. The increase of cultivated land mainly came from exploitation and land and arrangement and reclamation of industry and mining land (3) The economic development. population growth and policy are the dominant macro-driving factors for the decrease of cultivated land area in Yantai. The obvious sudden changes during the change process of cultivated land acreage are relevant to the national macro.policies background The rapid decrease of cnltivated land area is synchronous with the overheated economic growth resulting from the direct investment in fixed assets. Spatial distribution of the decrease in cultivated land is congruous with the differences in speed and the scale of economic growth between the different regions of Yantai area. Furthermore. the decrease in cultivated land caused by population increase cannot be ignored.