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1.
正China, one of the world's largest agricultural countries, inevitably generates a massive amount of agricultural solid waste(ASW) every year. As it is estimated, China annually produced 3.8 billion, 900 million and 200 million tons of livestock and poultry manure, crop straw, and agricultural product processing waste,  相似文献   

2.
With the development of China’s market economy, the international grain supply situation is increasingly tense, and the grain has been regarded as an important international strategic resource in the international market. Due to the reduction of international grain output and expected inflation, the gap between maize supply shortage and increasing demand is apparent in China, so that China is described as a worrying importer country. By using SWOT analysis belonging to the field of enterprise strategic management, this paper analyzed the current maize industry development in Heilongjiang Province as an entry point, the strength, weakness and opportunity and threat were put forward. Thereby, the developing principles and strategies were proposed to stimulate the maize industry development in Heilongjiang Province, which would lay a good foundation of 50 billion kilograms grain production capacity by 2015 in China, as well as the economic development and local farmers’ income increase.  相似文献   

3.
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正Biofumigation is an increasingly viable method for the control of plant-parasitic nematodes(PPNs)and offers an alternative to synthetic nematicides, including methyl bromide. PPNs damage crop yield and quality worldwide, with the financial toll of the pest estimated to be more than US$100 billion annually. The process of biofumigation acts through the growth and incorporation of  相似文献   

4.
<正> An intergeneric hybrid between Aegilops tauschti Cosson. an annual diploid grass. and Psathyrostachys huashanica Keng, a perenmal diploid grass. The F_1 hybrid plant had chromosome number of 2n=2x=14. and was annual and morphologically intermediate between two parents. Meiotic analysis showed that this F_1 hybrid had an average of 12.20 univalants, 0.12 rod bivalents ad 0.004 quadrivalents at MI of the pollen-mother-cells. Multipolar division, irregular ctyokinesis. conjungation opening and coenocyte were observed in this hybrid. These results suggested that the D genome in the Ae. tauschii was distantly related to the N genome in the P huashanica.  相似文献   

5.
Hunan Province lies in the south of the middle reaches of Changjiang River (Yangtze River) and the south of Dongting Lake, in 108°47′-114°15′(E) and 24?9′ -30°08′(N). It borders on Jiangxi Province in the east, provinces of Sichuan and Guizhou and Chongqing Municipality in the west, provinces of Guangdong and Guangxi the south and Hubei Province the north.With the territory ranking the l lth place in the country, Hunan covers 0.2118 million km2 of land area, including about 0.3267 million ha farmland,17.067 million ha mountainous and hilly areas and 1.334 million ha water areas. The province governs 14 administrative prefectures or cities, 136counties or districts, and has a population of 64.65 million, with 53.5 million of them, that is,83.8% of the province's total, engaging in agricultural production.  相似文献   

6.
Methiopyrisulfuron is a novel sulfonylurea herbicide with good activity for annual broadleaf and gramineal weeds control. Present study was to investigate the effects of organic amendments (including peat (PE), sewage sludge (SS), and humic acid (HA)) on adsorption, desorption and leaching of methiopyrisulfuron in soils. The batch equilibration technique was applied for adsorption-desorption experiments and the leaching was tested through soil column simulated experiments under laboratory conditions. The Freundlich model may well describe adsorption-desorption of methiopyrisulfuron on organic amendments, the natural soil, and amended soils. Organic amendments could not only greatly increase the adsorption capacity of methiopyrisulfuron, but also significantly enhance the hysteresis of desorption of methiopyrisulfuron. The correlations between Kf-ads and organic matter content of amended soils were significant, and the correlations between H and soil organic matter in amended soils with PE, SS, and HA were significant too. The results of soil column experiments indicated that organic amendments greatly decreased leaching of methiopyrisulfuron. This study suggested that PE, SS, and HA could greatly influence environmental behavior of methiopyrisulfuron in soils. Use of organic amendments might be an effective management practice for controlling potential pollution of methiopyrisulfuron to environment.  相似文献   

7.
Spatial and structural characteristics of plant communities in the steppe ecosystems of the Baikal region, Russian Federation have been researched in connection with climate change and grazing. The present study, based on a total of 15 typical steppe sampling plots, investigated above-ground biomass (AGB), below-ground biomass (BGB), total biomass (TB) and root:shoot ratios (R:S) and their relationships with climatic factors and grazing. All biomass components varied widely depending on the climatic parameters and the degree of grazing affected transformation. A strong negative correlation between mean annual temperature (MAT) and total plant biomass was revealed for all study area. Mean annual precipitation (MAP) signiifcantly affected communities productivity increasing only in the south of the region. Due to the large and mountainous territory, the inlfuence of latitude and elevation (mountain) factors on the components of the biomass were studied. Although all studied plant steppe communities were transformed by uncontrolled grazing, their productivity is signiifcantly reduced only at plots with maximum digression. Vegetation shift is an indicator of climate change, as well as providing a diagnostic tool to build predictive models. Based on the complex index of effective precipitation, it was revealed that at the end of last century in the steppes of the Baikal region the structural and production processes will be affected by an arid climate trend.  相似文献   

8.
The present research developed a bioeconomic model for control of Californian thistle (Cirsium arvense L. Scop.) in intensive, lowland sheep pastures in New Zealand. Production costs included two control methods: herbicides and defoliation, with defoliation encompassing both physical means and biocontrol measures. The model was used to examine the economic value of a research programme into biological control of the weed, given several different future scenarios. These scenarios were high herbicide prices, a price premium for lamb raised without chemical herbicides, and development of herbicide resistance. The model results were used to estimate national impacts. If the only change in the agricultural sector was the cost of the biocontrol to the nation's farmers, the research programme to find an effective biocontrol agent had little economic impact. If other factors changed, such as the price of petroleum or levels of herbicide resistance in the weed. the model's results suggested that intensive sheep farming could grow or shrink by as much as NZ$219 million dollars over five years. In the latter case, having an alternative control method reduced potential losses and increased potential gains, resulting in a net benefit of between NZ$81 million and NZ$153 million. This work extended prior research in several ways. First. Californian thistle reproduces via root buds, which affected the modelling of weed behaviour. Secondly, the model allowed optimistation over continuous levels of weed control for two different methods. Thirdly, the model accounted for both weed control and damage to nitrogen-fixing clover from herbicide use. Finally, the research investigated optimal weed control in several different alternative future states.  相似文献   

9.
The objective of this study was to analyze the water budget of a small basin in the northern of Loess Plateau. A small basin, Liudaogou in the northern Loess Plateau was chosen as the study area. The numerical calculation of surface runoff was applied to results of the field survey, and components of monthly water budget were estimated. The unit area of 1 km2 was selected as the index area for the estimation. A component of habitant water consumption was added to the water budget to consider the contribution of human activity. Results indicated that the water storage was negative in May, June and July while the annual amount was approximately 0.0. Evaportanspiration attained maximum in August and its annual total accounted for 74.2% of annual precipitation. Results of this study are significant for the sustainable water conservation and utilization in the northern of Loess Plateau where annual water resources are relatively deficient.  相似文献   

10.
《今日农村》2013,(2):54
You’ve been to both Beijing and Shanghai for tournaments.You even came to these two cities for MBA program.What’s your impression of China and the people? Do you think tennis is getting much more popular in the past 10 years? A:I am very interested in the Chinese culture and history.China has gone through an enormous economic development the last 30 years and according to an unofficial website,10 million people play tennis in China.That equals the entire population of Sweden.I think tennis will become more and more popular in China in the future. Firstly,the economy in China is growing extremely fast and the average Chinese are becoming more and more affluent.More  相似文献   

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