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1.
Nutrient pollution of air and water is a persistent problem in Europe. However,the pollution sources are often analyzed separately, preventing the formulation of integrative solutions. This study aimed to quantify the contribution of agriculture to air, river and coastal water pollution by nutrients. A new MARINA-Nutrients model was developed for Europe to calculate inputs of nitrogen(N) and phosphorus(P) to land and rivers, N emissions to air, and nutrient export to seas by river basins. Under ...  相似文献   

2.
Developing and developed countries alike are increasingly facing the dififcult question of how to feed more people amidst a host of emerging demographic, environmental, and health challenges. At the same time, in addition to food quantity, increased attention is being given to food quality attributes, in particular nutrition and safety. This is especially evident in China, where concerns are on the rise regarding the ability of China’s food production systems to deliver nutritious and safe food to a growing, urbanizing and more aflfuent population. These food and nutrition concerns come at a time when China is an increasingly inlfuential actor within the global food security network through activities such as production, consumption and trade. We argue that China has the opportunity to increase food and nutrition security both nationally and globally through a comprehensive policy agenda that focuses on institutional reforms, investments for and in agriculture, productive social safety nets, mutually beneifcial trade, and the exchange of know-how and technologies among developing countries and donors. This agenda will help China adapt its food production systems to the changing face of agriculture and to play a vital role in addressing the emerging challenges facing food and nutrition security within and beyond China in the coming decades.  相似文献   

3.
As contiguous area to Russia, Heilongjiang Province takes advantage of geography and resource superiority to promote the export of farmer labor services to Russia in recent years with trading cooperation between China and Russia. This paper briefly introduced the present situation of the export of farmer labor services from Heilongjiang Province to Russia. Under the background of Russian Far East economic development and development of "large agriculture" in Heilongjiang Province, Heilongjiang Province would continue to increase labor export to Russia. Then, the paper analyzed the problems of the export of farmer labor services and gave some proposals accordingly. At last, the result showed that well-organized and reasonable farmer labor export to Russia could play a role to the agricultural modernization and urbanization development.  相似文献   

4.
The responses of five inter-specific lowland rice cultivars (NERICA-L-19, NERICA-L-20, NERICA-L-41, NERICA-L-42, and NERICA-L-60) and four improved Oryza sativa cultivars (FKR 19, BW 348-1, WITA 4, and SIPI 6923033) to levels of phosphorus and nitrogen fertilization were compared on a Typic Natrustalfat Kadawa in the Nigerian Sudan Savanna in 2006 and 2007 The responses of the NERICA-L eultivars to N and P fertilization were similar to the O. sativa cultivars. In a dry year (2007), the NERICA-L cultivars gave higher yields than O. sativa cultivars. Phosphorus level did not significantly affect crop physiology, yield, and yield components of all the cultivars. Pooled across cultivars, N and P levels, days to panicle initiation, mid-flowering and maturity were, respectively delayed by 17.0, 15.6 and 6.4 days in 2007 compared to 2006. NERICA-L-42 and NERICA-L-41 were the most stable, exhibiting the least difference in duration to maturity between the two years (3.5 and 4.4 days, respectively), and could therefore be more adapted to rain-fed environments prone to frequent droughts. Increasing N levels from 0 to 120 kg hal produced yield increments of 62.9 and 37.2% in 2006 and 2007, respectively. Cultivars FKR 19 and WITA 4 gave higher yields in 2006 (3940 and 3542 kg ha^-1, respectively), while in 2007, NERICA-L-42, NERICA-L^-19 and NERICA-L-20 ranked among the highest in grain yield (3935, 3807 and 3726 kg hal, respectively) and could be recommended to resource-poor farmers. a  相似文献   

5.
Paclobutrazol was sprayed at 0,150,and 300 mg L~(-1) during the closed canopy stage and the early bud stage with two high-yielding cultivars of rapeseed,Yangguang 2009 and Fengyou 520.The impact of paclobutrazol on the accumulation and distribution of biomass and its relationship with yield,resistance to lodging and pod shattering were determined.All the treatments increased the resistance as well as yield.The maximum yield was obtained when paclobutrazol was applied during the closed canopy stage at 150 mg L~(–1).The plant’s resistance to both lodging and pod shattering was the maximum when paclobutrazol was applied during the early bud stage at 300 mg L~(–1).Paclobutrazol also delayed senescence,with the higher concentration or later spraying leading to more obvious effects;improved the net assimilation rate before the early bud stage;and promoted the relative growth rate of the main growth organ at each stage of growth and maximized the rate and quantities of biomass accumulation.However,at the higher concentration and later spraying,the increments were smaller.The spraying also increased the rates of biomass allocation to roots,leaves,and pods,but the rate of allocation to stems decreased as the plants grew shorter.The higher allocation to roots and the lower allocation to stems favoured resistance to both lodging and pod shattering whereas higher allocation to leaves and pods favoured yield.The higher concentration or late spraying led to excessive biomass being allocated to roots,which decreased leaf biomass during the bud stage,leading to greater resistance but lower yields.  相似文献   

6.
The dynamics of red edge parameters at different growth stages of wheat canopy was studied.The red edge position moved to the longer wavelength from erecting stage to heading stage, and returned to the original wavelength direction from grain-filling stage to maturity stage. The leaf total nitrogen content (LTN)is positively related to red edge amplitude (d λ red) and NIR platform amplitude (d λNIRP) and the correlation coefficient improved as growth stage extended. The chlorophyll content (TChl) is negatively related to d λ red from erecting stage to the elongation stage, and positively related to d λ red from heading stage to milky maturity stage. TChl is also positively related to d λNIRP. The leaf area index (LAI) is positively related to d λ red and d λNIRP, and the correlation coefficient improved as growth stage extended. It was concluded that d λ red and d λNIRP can be used as the indicators of winter wheat growth state, and guide the fertilization and irrigation decision making. The λNIRP is suitable for derivation of LTN, the d λ red for TChl, and the d λ red or d λNIRP for LAI.  相似文献   

7.
Chicken manure with similar content of copper and zinc was changes of organic carbon and humus substance complexed chosen to conduct a composting experiment to investigate the copper (HS-Cu) and zinc (HS-Zn), which were extracted by water (H2O), sodium hydroxide (NaOH), and sodium pyrophate-NaOH mixture (Na4P2O7-NaOH), sequentially. Distributions of copper and zinc in fulvic acids (FA) and humic acids (HA) in the three extracts were studied. During manure composting, the concentrations of copper and zinc increased from about 500 mg kg^-1 in the raw material to 1 100 mg kg^-1 in the final products. HS-Cu in H2O, NaOH, and Na4P2O7-NaOH extracts occupied 6.7, 26.7, and 19% averagely of total copper and HS-Zn represented 2.7, 13.7, and 17% averagely of total zinc in compost, respectively. In water extracts, both HA and FA mainly complexed with Cu and the mole ratio of Cu to Zn was 2.8 in HA fractions and was 2.6 in FA fractions, respectively. HA mainly complexed with copper, so that the ratios of HA-Cu to HA-Zn averaged 3.4 in NaOH extracts. FA had a similar potential to complex with copper and zinc, so that the ratio of FA-Cu to FA-Zn was close to 1. In Na4P2O7-NaOH extracts, HA or FA had a similar potential to complex with copper and zinc. The ratio of HS-Cu to HS-Zn was close to 1. With manure composting, Na4P2O7-NaOH extractable HS-Zn increased to a level as high as HS-Cu. This indicated that more and more stable complexes of HS-Zn were formed in the late decomposition period. The competition between copper and zinc to be complexed with humic substance became weaker and weaker with the decomposition process.  相似文献   

8.
Financing Sustainable Agriculture Under Climate Change   总被引:2,自引:1,他引:1       下载免费PDF全文
Agriculture is facing great challenge in meeting global food security and is expected to face even greater challenge under climate change. The overall goal of this paper is to examine how finance can be used to achieve the joint objectives of development, mitigation of and adaptation to climate change in agriculture in developing world based on literature review. The results show that agriculture is much under invested and foreign aid also has not increased appropriately to assist developing countries to maintain sustainable agriculture under climate change. There are a wide range of areas in mitigation of and adaptation to climate change that need substantial investment. Major areas and successful cases mitigation of and adaptation to climate change in agriculture that have worked in developing countries are examined. A list of areas that have worked, could work and be scaled up or transferred is identified and discussed. This study concludes that mainstreaming agricultural mitigation and adaptation into agricultural development programs, enhancing local capacity, and considering different stakeholders' needs are major experiences for successfully financing sustainable agriculture under climate change.  相似文献   

9.
Resistance of five field populations of Mythimna separata(Walker) collected from Shaanxi and Shanxi provinces of China to six different insecticides was evaluated by leaf dip method in the laboratory. The results showed that all populations were relatively sensitive to emamectin benzoate with a resistance ratio(RR) of 0.583–1.583 folds. All populations showed susceptible or low level resistance to chlorantraniliprole and beta-cypermethrin. Compared with a relatively susceptible strain of M. separata, the resistance level of the whole populations ranged from susceptible to moderate to chlorpyrifos and lambda-cyhalothrin, moderate to high to phoxim(RR=19.367–70.100) except for population from Sanyuan County(RR=2.567). Pair-wise correlation analysis among different insecticides indicated that chlorpyrifos has a significantly positive and significant correlation with emamectin benzoate. Chlorantraniliprole didn't have significant correlation with emamectin benzoate, chlorpyrifos and phoxim. Therefore, emamectin benzoate, chlorantraniliprole and beta-cypermethrin are recommended to control oriental armyworm. Meanwhile, to postpone the occurrence and development of insecticide resistance in Shaanxi and Shanxi provinces, alternative and rotational application of insecticides between chlorantraniliprole and emamectin benzoate or chlorpyrifos is necessary.  相似文献   

10.
A case study of 350 farmwomen in Croatia was conducted to contribute the understudied area of farming and entrepreneurship. The study considered the sociodemographical features of farmwoman and its influence on entrepreneurial and organization skills. Field research was conducted through a questionnaire and interviews. Results showed that farmwoman were keen to start innovations, use new technologies and start new income generating farm activities but their gender roles and process of socialization hinders them in such attempts. High statistical correlations were significant for sociodemographic status to entrepreneurial abilities like farm work organization, actual professional status to involvement in decision making and farm economic status to farm economical position (income).  相似文献   

11.
Understanding the changes in agronomic and physiological traits associated with yield genetic gain is important for soybean production and future breeding strategy. The objective of this study was to compare the older and modern cultivars to learn whether the yield improvements depend on preplant fertilizer or the plant productivity improvement, A set of older cultivars, with their modern counterparts derived from breeding programs in Liaoning and Ohio were evaluated for their agronomic and physiological traits under different fertilizer levels from 2004 to 2006. There was no improvement of response to N and P preplant fertilizer for genotypes. After more than 70 yr breeding, soybean breeders made some improvements in agronomic and physiological traits that contribute to yield increase. When compared to older cultivar, modern Liaoning and Ohio cultivars were shorter and more resistance to lodging, had greater leaf density, higher harvest index, more leaf area per plant, and greater photosynthetic rate, transpiration rate and stomatal conductance at the beginning of seed development. Ohio cultivars were more resistant to lodging as if selected for easy harvest by combine, even under high N and P preplant fertilizer level, which resulted in Ohio cultivars with higher and stable yield productivity.  相似文献   

12.
Effect of application of K fertilizer and wheat straw to soil on crop yield and status of soil K in the plough layer under different planting systems was studied. The experiments on long-term application of K fertilizer and wheat straw to soil in Hebei fluvo aquic soil and Shanxi brown soil in northern China were begun in 1992. The results showed that K fertilizer and straw could improve the yields of wheat and maize with the order of NPK + St 〉 NPK 〉 NP + St 〉 NP, and treatment of K fertilizer made a significant difference to NP, and the efficiency of K fertilizer in maize was higher than in wheat under rotation system of Hebei. In contrast with Shanxi, the wastage of soil potassium was a more serious issue in the rotation system in Hebei, only treatment of NPK + St showed a surplus of potassium and the others showed a wane. K fertilizer and straw could improve the content of water-soluble K, nonspecifically adsorbed K, non-exchangeable K, mineral K, and total K in contrast to NP; however, K fertilizer and straw reduce the proportion of mineral K and improve proportion of other forms of potassium in the two locating sites. Compared with the beginning of orientation, temporal variability character of soil K content and proportion showed a difference between the two soil types; furthermore, there was a decrease in the content of mineral K and total K simultaneously in the two locating sites. As a whole, the effect of K fertilizer applied to soil directly excelled to wheat straw to soil. Wheat straw to soil was an effective measure to complement potassium to increase crop yield and retard the decrease of soil K.  相似文献   

13.
A new chemical index-imbalance degree(IBD),was proposed on the basis of cluster analysis in multivariate statistical analysis to estimate the extent of amino acid balance in protein.The range of IBD is between 0 and 1,successively corresponding to complete baance and entire imbalance for the amino acid profile of a sample.The amino acid increment model of IBD belongs to an asymmetrical maximum-type,and there is a high correlation between IBD and coefficient of variation(CV),The nutritional Value of individual feed can be ranked and clustered according to its IBD;and by calculating the IBD of amixed sample with two or more feedstuffs,it is possible theoretically to predict whether a synergetic phenomenon exists and when an optimal mutual complement can happen.If the conceptive frame of IBD extended,it can be used to study the balance of plement can happen.If the conceptive frame of IBD extended,it can be used to study the balance of nutrients besides amino acids,and is helpful to realize the automatic distinction and selection in diet formulating.  相似文献   

14.
The purpose of this work is to perform a detailed study of carbohydrate specificity of the new extracellular bacilli lectins which is considered to determine mechanisms of the lectins action. Sources of lectins were bacterial strains from Ukrainian collection of microorganisms. The optimized protocol of bacilli lectins isolation and purification included precipitation with ammonium sulfate with subsequent gel filtration chromatography on Sepharose CL-6B. Hemagglutinating activity of bacilli lectins and their fine carbohydrate specificity to sialic acids and their derivatives as well as sialic asid-containing and asialic glycoconjugates were studied. The ability of extracellular bacilli lectins to discriminate a- and 13-conformation of carbohydrate molecule and the type of connection between the monomers was determined. Studied lectins showed the most affinity to glycoconjugates containing both types of sialic acids (N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (NeuGc)) and it is supposed to be a basis of their diagnostic and analytical potential.  相似文献   

15.
Plant disease management faces ever-growing challenges due to:(i)increasing demands for total,safe and diverse foods to support the booming global population and its improving living standards;(ii)reducing production potential in agriculture due to competition for land in fertile areas and exhaustion of marginal arable lands;(iii)deteriorating ecology of agro-ecosystems and depletion of natural resources;and(iv)increased risk of disease epidemics resulting from agricultural intensification and monocultures.Future plant disease management should aim to strengthen food security for a stable society while simultaneously safeguarding the health of associated ecosystems and reducing dependency on natural resources.To achieve these multiple functionalities,sustainable plant disease management should place emphases on rational adaptation of resistance,avoidance,elimination and remediation strategies individually and collectively,guided by traits of specific host-pathogen associations using evolutionary ecology principles to create environmental(biotic and abiotic)conditions favorable for host growth and development while adverse to pathogen reproduction and evolution.  相似文献   

16.
ue to deficiency of qi and kidney essence respond well to Qiusi Elixir,and general condition of patients were built up to varied degree after medication.Barr  相似文献   

17.
For centuries, groups of people desiring to supply themselves with goods, to market their products, or to obtain services of various kinds on a co-operative basis, have made increasing use of co-operative associations to achieve these purposes. During the period, legislation designed especially for the incorporation and conduct of such associations has been enacted by different counties. Since a co-operative is established and carried on by and for the use of its members, this essay makes a comparison between Canadian and Chinese co-operative laws in terms of membership in the aspects of qualifications, rights and obligations and withdrawal of membership, so as to probe the function of co-operative legislation and find some enlightment from it.  相似文献   

18.
The study reflects on previous World Bank and FAO reports that made the general recommendation to set both research and extension investment targets in developing countries at 1% of agricultural gross domestic product (AgGDP). In order to define proxies for country-specific extension investment targets, authors developed an extension investment model (EIM) based on socio-economic macro-indicators (poverty, undernourishment, access to information and population density) and a method to define estimates for cost increases related to climate change. These parameters helped estimating the demand for agricultural extension and investments required for it. Results showed that about half of the 94 developing and emerging countries should spend more than 1% of their respective share of GDP derived from agriculture and about a quarter of the countries, mostly in Africa and South East Asia, need to spend more than 2% of their AgGDP. The paper reveals significant differences in average investment requirements in different regions and shows the additional extension costs related to climate change and other areas that currently lack investment.  相似文献   

19.
China has the largest apple planting area and total yield in the world, and the Fuji apple is the major cultivar, accounting for more than 70% of apple planting acreage in China. Apple qualities are affected by meteorological conditions, soil types, nutrient content of soil, and management practices. Meteorological factors, such as light, temperature and moisture are key environmental conditions affecting apple quality that are difficult to regulate and control. This study was performed to determine the effect of meteorological factors on the qualities of Fuji apple and to provide evidence for a reasonable regional layout and planting of Fuji apple in China. Fruit samples of Fuji apple and meteorological data were investigated from 153 commercial Fuji apple orchards located in 51 counties of 11 regions in China from 2010 to 2011. Partial least-squares regression and linear programming were used to analyze the effect model and impact weight of meteorological factors on fruit quality, to determine the major meteorological factors influencing fruit quality attributes, and to establish a regression equation to optimize meteorological factors for high-quality Fuji apples. Results showed relationships between fruit quality attributes and meteorological factors among the various apple producing counties in China. The mean, minimum, and maximum temperatures from April to October had the highest positive effects on fruit qualities in model effect loadings and weights, followed by the mean annual temperature and the sunshine percentage, the temperature difference between day and night, and the total precipitation for the same period. In contrast, annual total precipitation and relative humidity from April to October had negative effects on fruit quality. The meteorological factors exhibited distinct effects on the different fruit quality attributes. Soluble solid content was affected from the high to the low row preface by annual total precipitation, the minimum temperature from April to October, the mean temperature from April to October, the temperature difference between day and night, and the mean annual temperature. The regression equation showed that the optimum meteorological factors on fruit quality were the mean annual temperature of 5.5–18°C and the annual total precipitation of 602–1 121 mm for the whole year, and the mean temperature of 13.3–19.6°C, the minimum temperature of 7.8–18.5°C, the maximum temperature of 19.5°C, the temperature difference of 13.7°C between day and night, the total precipitation of 227 mm, the relative humidity of 57.5–84.0%, and the sunshine percentage of 36.5–70.0% during the growing period(from April to October).  相似文献   

20.
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