2022年农学英文文献及全文翻译 .pdf

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1、沼液浸种和根外追肥对玉米农艺性状和产量的影响研究- 1 - 英文文献：Household biogas use in rural China: A study of opportunities and constraints Yu Chen a,c, Gaihe Yang b,c,*, Sandra Sweeney a, Yongzhong Feng b,c ABSTRACT：As a renewable energy, biogas is not only an important part of the development of rural new energy, but also a

2、n important aspect of sustainable development in China. The development process and present status of household biogas, specifically the opportunities and constraints of household biogas in rural China, are discussed in this paper. Only about 19% of the biogas potential has been utilized in rural Ch

3、ina.There are several opportunities for household biogas development in rural China, including the problem of rural household energy consumption, the availability of biogas fermentation materials, national financial subsidies, legal and international clean development mechanisms. Also, more research

4、 needs to be done in straw fermentation and cold fermentation technology. Training should be conducted to raise the level of biogas customers in comprehensive biogas utilization. Measures should be taken to improve the follow up services and management of biogas plants. The information presented in

5、this paper will be helpful not only to the sustainable development of household biogas in rural China, but also to the development of biogas in similar countries around the world. 1.Introduction The development and utilization of renewable energy resources has becoming an important component of a su

6、stainable global energy strategy 1. In 2006, about 18% of global final energy consumption came from renewables, with 13% coming from traditional biomass 2. China has a long history of renewable energies use including biomass, solar, geothermal, ocean and wind energy 1. These resources represent mass

7、ive energy potential,which greatly exceeds that of fossil fuel resources 3. Biogas is distinct from the other renewable energies on two fronts: one, it is a comparatively clean high methane fuel, and two, it is important in the collection of organic waste material from which both fertilizer(s) and w

8、ater for agriculture uses can be produced 4. As the strategy applying of building new socialism rural and sustainable agriculture in 21 century, The development of rural household biogas is an important way to promote agricultural structural adjustment, increase rural incomes, enhance the ecology of

9、 rural areas, and improve the quality of both rural life and agricultural products 5. The number of household biogas plants in rural China is the highest in the world 6. By 2007, there were 26.5 million biogas plants, whose output had reached 10.5 billion m3 (equivalent to more than 100 million tons

10、 of standard coal). Household biogas digesters are found throughout the country, mainly in the Yangtze River Basin. Sichuan Province has the largest number of biogas plants, with 2.94 million running 7. The rapid development of biogas is closely tied to the country?s rich experience in developing bi

11、ogas, the availability of large amounts of fermentation materials, and the strong support of state funds. However, limiting factors still exist. In this paper, we present research on the development process and present status of household biogas in rural China, concentrating on current opportunities

12、 and constrains. 2. Household biogas use in China 2.1. Household biogas development process 名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 1 页，共 11 页 - - - - - - - - - 沼液浸种和根外追肥对玉米农艺性状和产量的影响研究- 2 - The research and use of biogas in China has a long history, and the u

13、se of hydraulic digesters has been in use for nearly a 100 years 8. In the 1880s, the first test to ferment biogas was undertaken in Guangdong. Rectangular hydraulic digesters were invented by Luo GuoRui in 1920 in Taiwan, China. A chronology of biogas development events in China is shown in Table 1

14、. Table 1. Chronology of biogas development in China. Year Biogas related activity 1880s The first test to ferment biogas took place in Guangdong Close of 19th century The simple biogas digester appeared 1920 Rectangular hydraulic digesters were invented by Luo GuoRui in Taiwan, China 1929 First Chi

15、nese institutions to promote biogas established 1931 Biogas was popularized throughout the country for the first time 1933 The training of biogas technology was begun 1958 Biogas was popularized throughout the country for the second time; biogas research institutes established 1970s Biogas was popul

16、arized throughout the country for the third time 2000 The Ministry of Agriculture proposed the “ Biologically Enrichment of the Countryside Project” 2003 The Ministry of Agriculture proposed the“ Rural Household Biogas State Debt Project”2007 The Ministry of Agriculture proposed the “ Project of Rur

17、al Biogas Project”The large-scale development of household biogas in China began in the 1970s 9. Fig. 1 shows the number of biogas digesters installed between 1973 and 2005 in China 10. From 1973 to 1983 development fluctuates dramatically; from 1984 to 1994 an adjustment period follows characterize

18、d by slow development;from 1995 to 2000 the pace of development steadily increased annually; and by the 21st century, the construction of household biogas digesters had entered a new, sustained and rapid stage. Fig. 1. Number of biogas plants installed in China modified after 11. 2.2. Household biog

19、as digester design Luo GuoRui type biogas digesters were set up in 1920s 8. This hydraulic biogas digester, constructed of clay, brick, and concrete, was widely used in rural areas in the 1970s 7. By Chinese national standards, this biogas digester was constructed in 6, 8 and 10 m3 volumes, and note

20、d in the world for ,China?s model of biogas digester? 11.In 2000, commercial household biogas digesters made of glass fiber reinforced plastics (GRP) entered the market 12. The GRP digester has a thickness of 6 8mm, a tensile strength of 93.5MPa,and a bending 名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - -

21、 - - - - - - - - 名师精心整理 - - - - - - - 第 2 页，共 11 页 - - - - - - - - - 沼液浸种和根外追肥对玉米农艺性状和产量的影响研究- 3 - strength of 109 MPa. The volume range is from 6 to 10 m3 13. A comparison of the key technical indices between the concrete digester and the GRP digester is shown in Table 2 13. From Table 2 we can see

22、 that GRP digester has a lower coefficient thermal conductivity, a longer operational life, lower maintenance costs, and a shorter construction cycle than the concrete one. Table 2. The compare of the key technical indexes between concrete digester and GRP digester. The style of biogas digester The

23、thick- ness of the wall (cm) Thermal conductivity (kJ/min) Volume (m3) Operation life (a) Construction cycle (d) Price (Yuan) Weight (kg) Materials Maintenance Concrete digester 10 5.44 8 20 10 1800 200 40 clay, brick, concrete 2 3a need a small maintenance 45a need a big maintenance GRP digester 81

24、0 1.42 8 2030 0.5 1700 200 glass fiber reinforced plastics No need to maintenance 2.3. Household biogas eco-agricultural models 2.3.1. ,Three in One? eco -agricultural model The ,Three in One? eco-agricultural model, which combines the biogas digester with a pigpen and toilet, is popular in southern

25、 China 14. The main purpose of this model is simultaneously to solve the rural energy crisis and to improve household hygiene in the rural environment. Biogas can be used as fuel for lighting and cooking, as a fertilizer for growing fruit trees, vegetables and grain, and as a pest control agent 11.

26、Green food can be developed from the pattern. By connecting the toilet to the biogas plant the spread of disease caused by mosquito breeding can be eliminated. To some extent, it also prevents the occurrence of infectious diseases and the contamination of drinking water by human and animal fecal mat

27、ter. The ,Three in One? eco-agricultural model construction requires less capital input and is quickly effective, which has both strenghtened utility and extended value in the poor economic conditions of the area 14. 2.3.2. ,Four in One? eco -agricultural model The ,Four in One? eco-agricultural mod

28、el, which combines the biogas digester, pigpen, solar greenhouse, and toilet, has been proposed for northern China 15. The greenhouse in this model can be used to increase the temperature of the biogas digester increasing the efficiency of cold weather biogas production. Biogas can be used to increa

29、se the temperature of greenhouses. With the temperature of greenhouses increased, vegetables can grow well and pigs are well-fed 16. Used as a spray for vegetables, the slurry inhibits disease and boosts yields 17. Because solar greenhouse construction requires a larger 名师资料总结 - - -精品资料欢迎下载 - - - -

30、- - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 3 页，共 11 页 - - - - - - - - - 沼液浸种和根外追肥对玉米农艺性状和产量的影响研究- 4 - input of capital and the growth of greenhouse vegetables more water this model is suitable for regional development in the North where solar energy is abundant, better economic conditions pr

31、evail, and water resources are available 18. 2.3.3. ,Five in One? eco-agricultural orchard model The ,Five in One? eco-agricultural orchard model, which combines the biogas digester with solar-powered barns, watersaving irrigation system, water cellar, and toilet is proposed for northwest China 19.

32、Biogas fertilizer is used to grow fruit trees to improve the quality of the fruit 20. Water resources collected in a water cellar are used in the biogas fermentation, orchard spraying and irrigation. The introduction of water-saving devices, greatly ease the pressure on water resources especially th

33、ose created by the demands of orchard irrigation making this model is suitable for regional development in the Northwest where severe water shortages exist 21. 3. Opportunities for household biogas use in China In 2007, 60% of Chinas population or 0.9 billion people lived in rural area China. The pe

34、r capita consumption of standard coal is 960 kg, of which 539 kg or 56% is used for daily life, from which straw accounted for 32.8%, fuel wood 21.2%, coal 34.3%, and biogas a mere 1.5% 7. According to Chinas rural biogas planning project (2006 2010), by 2010, 0.139 billion rural households are suit

35、able for biogas construction. However, only about 2.65 million households are presently using biogas meaning that only about 19% of the biogas potential of rural China has been achieved 22. 3.1. The problem of rural household energy consumption Over the long-term, rural household energy consumption

36、in China has mainly depended on traditional biomass energy, such as straw and firewood 23. At present, straw still accounted for 32.8%, fuel wood accounted for 21.2% and coal accounted for 34.3% of the total consumption 7. The three energy sources were mainly used for cooking and house heating, whic

37、h leads to low-energy efficiency and serious environmental degradation. For cooking, the thermal efficiency of straw and firewood is about 20%, and of coal is 30%, but that of straw and firewood is only about 10% if they are burned in traditional stoves 24. Today, mankind faces two major global clim

38、ate problems: global warming which is mainly caused by emissions of CO2, and acid rain, caused by emissions of SOx as well as NOx. The direct buring of straw and firewood leads to large emissions of CO and other toxic gases. Coal combustion is not only an important source of CO2emissions, but also t

39、he main source of increases in SO2emissions 25. Apart from that, coal is also facing the danger of exhaustion. Faced with these problem, we must enhance the efficiency of the conventional energy and increase the proportion of renewable energy sources in the total energy budget. 3.2. Opportunities fo

40、r renewable energy policy 3.2.1. Financial subsidy By the 21st century, the Chinese government had begun to focus on supporting rural biogas projects. In 2003, the Central Treasury decided to implement the rural biogas projects. The programs will have invested 61 billion RMB from 2003 to 2010, of wh

41、ich 15 billion RMB is from the National Investment Fund 26. In 2003, the Ministry of Agriculture Development and Reform Commission started the Project of Rural Household Biogas State Debt and invested 840 million RMB for the construction of household biogas in 22 provinces (autonomous regions and mu

42、nicipalities). In 2004, the movement continued to provide 1 billion RMB of national debt for constructing rural household biogas digesters; in 2005, central investment in the construction of rural biogas funds rose to 2.5 billion Yuan, of which 2 billion was slated for the construction of household

43、biogas digesters and 0.5 billion for the construction of large and 名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 4 页，共 11 页 - - - - - - - - - 沼液浸种和根外追肥对玉米农艺性状和产量的影响研究- 5 - medium-sized biogas digesters 9. As Rural Biogas Construction State Debt Program Management Me

44、thod stipulates, central fin ance subsidizes the “ one pool and three reforms” in accordance with the following standards: 1200 RMB/household in the northwestern and northeastern areas, 1000 RMB/household in the southwestern area and 800 RMB/household in other areas 27. 3.2.2. Law on renewable energ

45、y On 28 February 2005, PRC Law on Renewable Energy, bringing the exploitation and use of renewable energy to the strategic height of “ increasing energy supply, improving energy structure, guaranteeing energy safety, protecting the environmental and realizing the sustainable development of economy a

46、nd society” 28.3.2.3. Clean development mechanism To tackle the problem of global warming, the clean development mechanism (CDM) was put forward in Kyoto Protocol. The clean development mechanism (CDM) is an arrangement under the Kyoto Protocol allowing industrialised countries with a greenhouse gas

47、 reduction commitment (called Annex B countries) to invest in projects that reduce emissions in developing countries as an alternative to more expensive emission reductions in their own countries. As a consequence, the development of CDM biogas technology projects and the sale of verified carbon emi

48、ssion reductions (CER) has opened up new channels of finance for medium-sized biogas project in China, including household biogas digesters in rural areas, leading to an increase projects rate of economic return. 3.3. Biogas fermentation material availability Livestock and poultry manure, most of wh

49、ich is from cattle, pigs and chicken, and agricultural residues are the main resource for biogas fermentation in rural China. The potential quantity of manure can be estimated by the number of livestock and poultry and the annual dry excrement production of one livestock or poultry 29. Calculated ac

50、cording to current livestock and poultry production, the total physical quantity of dry excrement resources in China is 1467 million tons, of which 1023 million tons can be collected, equivalent to 107 million tons of standard coal 30. According to the plan for livestock industry development, livest