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1.
The possibility of calculations for an agroindustrial complex under conditions of an unknown distribution function is found. Estimations are made for a number of natural and technological processes of an agricultural complex by means of generalizations of Chebyshev’s and Kolmogorov’s inequalities.  相似文献   

2.
The purpose of this paper is to document the likely impacts of climate change on China＇s agriculture and the current adaptation efforts made by government and farmers. The review of literature shows that climate change will have a significant impact on agriculture, primarily through its effect on crop yields. The extent of predicted impacts highly depends on the crop, the CO2 fertilization effect assumption and adaptation abilities. Market response to the production shocks resulting from climate change will lessen the impacts on agricultural production predicted by natural scientists. On adaptation, the government＇s major efforts have been in the developing new technologies, reforming extension system and enhancing institutional capacity. Farmers do adapt to climate change, but their adaptation measures cannot fully offset the negative impacts of climate change. The paper concludes and makes implications for future studies.  相似文献   

3.
Ambitious targets to reduce greenhouse gas (GHG) emissions from agriculture have been set by both national governments and their respective livestock sectors. We hypothesize that farmer self-identity influences their assessment of climate change and their willingness to implement measures which address the issue. Perceptions of climate change were determined from 286 beef/sheep farmers and evaluated using principal component analysis (PCA). The analysis elicits two components which evaluate identity (productivism and environmental responsibility), and two components which evaluate behavioral capacity to adopt mitigation and adaptation measures (awareness and risk perception). Subsequent Cluster Analyses reveal four farmer types based on the PCA scores. ‘The Productivist’ and ‘The Countryside Steward’ portray low levels of awareness of climate change, but differ in their motivation to adopt pro-environmental behavior. Conversely, both ‘The Environmentalist’ and ‘The Dejected’ score higher in their awareness of the issue. In addition, ‘The Dejected’ holds a high sense of perceived risk; however, their awareness is not conflated with an explicit understanding of agricultural GHG sources. With the exception of ‘The Environmentalist’, there is an evident disconnect between perceptions of agricultural emission sources and their contribution towards GHG emissions amongst all types. If such linkages are not conceptualized, it is unlikely that behavioral capacities will be realized. Effective communication channels which encourage action should target farmers based on the groupings depicted. Therefore, understanding farmer types through the constructs used in this study can facilitate effective and tailored policy development and implementation.  相似文献   

4.
According to the analysis of published materials, the design with an attachable chisel has enjoyed the broadest use because it has a monolithic nose part with an additional component (chisel) that provides extra strength to this area. The force impact of the soil environment on the facial surface of the plowshare nose is analyzed. In most cases, the plowshare fails by breakdown and deformation in the zones of the nose and the first fastener hole. According to the theory of elasticity, this hole is the point of support for the cantilever beam with an arm extended from the first fastener hole to the blade perpendicular to the weak section line. The cantilever beam with regard to the plowshare nose is a triangle with a continuously increasing cross section from the blade to the first fastener hole; that is why failures may occur in any point along the arm line, whatever the arm length. It has been established that, when the chisel is mounted on the plowshare with side faces made parallel to the landward edge line, the strength of the tip increases on the plowshoe with all the fastener holes arranged in a single line, but the zone of the first fastener hole becomes weaker because extra force is generated that produces the bending torque and the rotational torque under the soil pressure. It has been shown that the plowshare strength in the zone of the first fastener hole is increased by mounting the attachable chisel so that the line along the side faces of the chisel splits the chisel into two equal parts by form and area and passes through the first fastener hole perpendicularly to the weak section and crosses the holes for fastening the chisel to the plowshare frame. Thus, the forces that cause the bending torque in the cantilever beam fastening point, i.e., in the first fastener hole, will be active only along one line perpendicular to the weak section line. This way the strength in the weak section zone close to the first fastener hole will increase because the impact of other extra soil forces will be minimized.  相似文献   

5.
Data on irrigated saline soils of the Mugan-Sal’yany Massif (Azerbaijan) and factors of its salinization are given. The studies enabled the revealing of diagnostic parameters of irrigated meadow-serozemic and alluvial-meadow soils of the massif. The structure of its profile is AYa'ca z–AYа"ca z–Bca z s m–BCca cs–Cs ca and AUa'z–AYa"z–Bca g–BCg–Cs ca, respectively. It has been revealed that the areas with unsatisfactory status of drainage and irrigation networks are characterized by a rise in groundwater level and mineralization and in salt content in soil as well as by poorer water-physical and chemical soil properties. The operation of the existing drainage system and the regular water drain into a collecting system should be organized in order to improve water-physical soil properties. In the areas where drainage systems cannot be repaired, temporary drains (0.8–1.0 m deep) at a distance of 25–50 m from one another and temporary collecting reservoirs (1.0–1.5 m deep) are recommended. It is necessary to provide discharge of irrigation water into constant drains. Taking into consideration the increase in salt content in the entire area, furrowing, sprinkling, and other irrigation methods are useful.  相似文献   

6.
【Objective】The aim of this study was to identify the typical indices of fruit quality and high quality materials of ‘Yangjiaocui’ melons to provide reference and basis for melon quality evaluation and breeding. 【Method】Eighteen indices, including economic trait and flesh quality of fruits from 6 cultivars and 26 high-generation inbred lines of ‘Yangjiaocui’ melons were determined. Based on factor analysis, stepwise regression, correlation analysis and two-dimension ordination map, the typical indices of fruit quality and high quality materials were identified. 【Result】 Among the 18 indices, single fruit mass, hardness, vitamin C (VC) content, titratable acid content, sugar-acid ratio and solid acid ratio showed greater variability, and the variation coefficients were more than 20%. However, the variability of fruit transverse diameter, flesh thickness rate and pH were relatively lower and the variation coefficients were less than 10%. Three common factors were extracted from economic trait indices with 87.71% cumulative variance contribution rate and the explanatory indices were fruit longitudinal diameter, fruit transverse diameter, fruit shape index, fruit cavity longitudinal diameter, fruit cavity transverse diameter and flesh thickness rate. From quality indices, 4 common factors were extracted with 90.03% cumulative variance contribution rate and the explanatory indices were VC content, hardness, total soluble solids content, total sugar content, titratable acid content, sugar-acid ratio and solid-acid ratio. Based on the comprehensive analysis of these selected 6 economic trait indices and 7 flesh quality indices, 5 common factors were extracted with 87.35% cumulative variance contribution rate. According to the correlation among the indices and the principle of simplicity and ease of use and avoidance of overlapping information, 5 indices, including fruit longitudinal diameter, flesh thickness rate, hardness, total sugar content and titratable acid content, could be used as typical indices to evaluate the fruit quality of ‘Yangjiaocui’ melons. The comprehensive quality score of all materials were ranked depended on scores and variance contribution rate of the above 5 common factor and two-dimension ordination map. Finally, 10 materials were selected as high quality materials. 【Conclusion】 Fruit longitudinal diameter, flesh thickness rate, hardness, total sugar content and titratable acid content could be used as typical indices to evaluate fruit quality of ‘Yangjiaocui’ melons. Inbred lines 25, 24, 22, 21, 8, 1, 17, 18, 20 and 23 were high quality materials.  相似文献   

7.
Climate change is confronting African farmers with growing uncertainties. Advances in seasonal climate predictions offer potential for assisting farmers in dealing with climate risk. Experimental cases of forecast dissemination to African rural communities suggest that participatory approaches can facilitate understanding and use of uncertain climate information. But few of these studies integrate critical reflections on participation that have emerged in the last decade which reveal how participatory approaches can miss social dynamics of power at the community level and in the broader context. Furthermore, neither climate application research nor theoretical critiques of participation fully examine the culturally constructed nature of participation. Drawing on sociolinguistic analysis, in-depth interviews, and ethnographic observation, this paper examines how Ugandan farmers engage in participation in the context of discussions of seasonal climate forecasts. Forecasts were presented to farmers groups whose members were then asked to discuss the forecast among themselves. In doing so, groups sought to develop a common understanding of the forecast and consensual plans for response strategies. Focusing on one particular group meeting as an example, we show how different cultural styles of participation affect the interpretation of the forecast and the formulation of response strategies. Group interaction is shown to be mostly structured around two styles of participation. On the one hand, there is the “Western” style advocated by NGOs and the government, which centers on ensuring that all individuals who are present have opportunities to speak during discussion and to vote on group decisions. On the other hand, a “Kiganda” style of participation emphasizes the importance of affirming ties to a collectivity, respect for social hierarchy, deployment of good manners, and consensus building. The case study illuminates how the performance of different styles of participation is grounded in localized frameworks of language and culture but also draw on political and policy discourses at the national level. Although a cultural high value on consensus may work in favor of prominent members, the availability of multiple styles of participation also enables group members to exercise their agency in positive ways. Attention to the interplay of different styles of participation throws light on the subtle social processes that shape how knowledge is assessed, which sources are trusted, which and whose interpretations prevail, what options are deemed viable, how costs and benefits are calculated, and whose resources are mobilized in the effort to reduce vulnerability to climate risk. These are key questions for an assessment of the role of boundary organizations, such as farmer associations, in the communication and application of climate forecasts in agriculture.  相似文献   

8.
SHANG Yan  XIONG Tao 《农业科学学报》2021,20(12):3323-3338
Farmers’ assessments of risk management strategies and how the assessments influence their willingness to adopt these strategies are poorly understood. This study conducts a structured survey of 469 farmers to investigate how farmers assess both crop insurance and crop price insurance, the impact of the assessments on their adoption willingness, and in particular, the differences in assessments and adoption willingness between crop insurance and crop price insurance. Empirical results show that farmers’ assessments on crop insurance can be significantly improved through communication and experience. The most effective way to improve farmers’ assessments on crop price insurance is providing adequate information about the insurance products. Furthermore, farmers’ adoption willingness would be enhanced by improved assessment of both crop yield and crop price insurance. This study provides the first empirical evidence that farmers have limited information to assess insurance, which significantly influences their willingness to adopt. This finding reflects that the dissemination of insurance policies, the effectiveness of insurance, and the availability of insurance services significantly enable farmers’ ability to assess risk management strategies, which potentially increases farmers’ willingness to adopt insurance.  相似文献   

9.
A mechanism and operation principle of the original structure of the reclamation chisel-fertilizer is presented. The advantage of the design consists in the possibility of the uniform supply of the fertilizers and ameliorants to the plowing and subsurface soil layers, which ensures an increase of the fertile layer, improvement of the nutrition conditions of the plants, and, as consequence, an increase of the yield of the cultivated crops. The pressure supply of the ameliorants to the layer is carried out by a high-pressure fan with a pressure air duct, fertilizer tube, by which the fertilizer-air mixture is supplied under the A-blade. The ameliorants are supplied to the trapezoidal deformation zone of the subsurface soil layer created by the chisel working element below the furrow bottom. The calculation of the structural elements of the mechanism is given. The developed structure also allows for combining the operations on applying the ameliorants, which increase the complex criterion of energy efficiency to 15%. The use of the developed structure in the agricultural production allows keeping and restoring the soil fertility.  相似文献   

10.
Precision Agriculture - Hedgerow orchard is an olive growing system where trees are planted at a super high-density higher than 20-fold (i.e., 1200–2500 trees ha?1) compared to the...  相似文献   

11.
The food regime concept is a key to unlock not only structured moments and transitions in the history of capitalist food relations, but also the history of capitalism itself. It is not about food per se, but about the relations within which food is produced, and through which capitalism is produced and reproduced. It provides, then, a fruitful perspective on the so-called ‘world food crisis’ of 2007–2008. This paper argues that the crisis stems from a long-term cycle of fossil-fuel dependence of industrial capitalism, combined with the inflation-producing effects of current biofuel offsets and financial speculation, and the concentration and centralization of agribusiness capital stemming from the enabling conjunctural policies of the corporate food regime. Rising costs, related to peak oil and fuel crop substitutes, combine with monopoly pricing by agribusiness to inflate food prices, globally transmitted under the liberalized terms of finance and trade associated with neoliberal policies.  相似文献   

12.
The results of the study demonstrated the immunosuppression in albino rats under a complex impact of T-2 toxin and Salmonella, manifested by the significant increase of anti-inflammatory cytokine IL-1β content in the blood and a slight increase of IL-4, stimulating the humoral immunity, the decrease of concentration of other anti-inflammatory mediators (TNF-α, IL-8), immunoregulatory interleukins IL-2, interferon-γ and anti-inflammatory cytokine IL-10, and interferon–γ/IL-4 ratio, indicating an evident T-deficit and a more significant suppression of Th-1 lymphocyte function.  相似文献   

13.
为促进生态化城市建设和保证区域城市的可持续发展,采集西安市浐灞生态区主要地段0～20cm层次土壤,分别测定土壤pH值、有机质、碱解氮、速效磷、速效钾等指标,并采用改进的内梅罗指数对各地段的土壤肥力状况进行综合评价。结果表明：西安市浐灞生态区绿地人为扰动严重,其中：国家湿地公园的土壤肥力属于贫瘠水平;浐河西路、大道（浐灞大道、广运潭大道、欧亚大道）、北辰路、灞河西路、灞柳路、雁鸣湖2号湖湖心岛、雁鸣湖垃圾山、雁鸣湖5号湖预留湿地地段的土壤肥力属于一般水平;雁鸣湖3号湖西岸土壤肥力属于肥沃水平;土壤有机质是浐灞生态区土壤肥力的限制因子。针对上述分析结果,本研究提出了相应的建议和改良措施。  相似文献   

14.
The genetic polymorphism of 12 microsatellite loci was revealed and unique DNA-profiles were obtained for initial lines of sugar beet. Two loci were monomorphic, other loci exhibited polymorphism. The genetic distances between the breeding materials were determined; the dendrogram of cluster analysis reflecting the probable divergence of samples was constructed. The data about the distance of the selection material will be used in the selection of pairs in heterotic breeding.  相似文献   

15.
Many consumers are motivated to attend Farmers’ Markets (FMs) because of the opportunity to purchase fresh and local products. The subsequent interactions at FMs provide an important pathway for the direct exchange of information. While previous research suggests that people value local food and the FM shopping experience and that purchasing directly from producers can lead to transformative learning, little is known about exactly how the shopping experience at FMs can influence consumer purchasing behavior. This study examines the extent of and mechanism for such “influencing.” Using data from surveys, observations, and interviews gathered at six FMs, we analyze the interactions between consumers and vendors, including the motivations and values of both parties. We explore the question, “How do farmers’ markets facilitate change in consumer purchasing behavior?” We propose that the dynamic of change in consumer purchasing behavior at FMs takes root in the exchange of information between consumers and vendors during interactions. Our results suggest that there are three specific characteristics shared by FM consumers and vendors that lead to these meaningful interactions at FMs: symmetry of motivations to attend FMs, shared values, and mutual dependence on interactions. Then, when a consumer learns new information from a FM vendor during an interaction, the consumer is more likely to make a change in their immediate purchase. Information about the products for sale and the modes of production of those items can especially impact consumers’ immediate purchases at FMs. We found that FM interactions can also impact long-term purchasing behavior, such as purchasing more organic or locally produced foods. Our results suggest that FM interactions may have significant implications for consumer health, local economies, and the environment.  相似文献   

16.
《农业科学学报》2023,22(8):2553-2566
Understanding the factors behind apple farmers’ willingness to pass on the management of their farms to their descendants is crucial to the continuity of apple production. Due to the high specificity of the human capital, physical assets, land assets, and geographical location in apple production, this study used a binary logistic regression and a mediating effect model to explore the impact of asset specificity on farmers’ intergenerational succession willingness of apple management (FISWAM) and to examine the mediating effects of loss aversion in the impact of asset specificity on the FISWAM. The results showed that about 18.68% of the respondents expressed willingness to transfer their apple business between generations, and the FISWAM was generally weak. In addition to the negative impact of geographical location specificity (GLS), human capital specificity (HCS), physical assets specificity (PAS), and land assets specificity (LAS) can enhance the FISWAM. Loss aversion plays a partial mediating role in the impact of PAS, LAS, and GLS on the FISWAM.  相似文献   

17.

Aims  

To promote the value of farm manure through investigating its effect on soil health using statistical methods.  相似文献   

18.
Turpan is one of the major high-quality grape production bases in the world for years because its climate is so special (hot, dry, and windy). The grape market needs the varieties with high yield, quality, and environmental adaptability. ‘Xinyu’ is a new variety bred by crossing selection of E42-6 (a self-pollinated inbred of Vitis vinifera cv. ‘Red Globe’) as female and Vitis vinifera cv. ‘Rizamat’ as male parents and registered in the Crop Varieties Registered Commission of Xinjiang Uygur Autonomous Region in 2005. In this study, we determined the impacts of environmental factors on its photosynthesis. The results showed the climate in Turpan was characterized by long-time intensive sunshine, high temperature and relatively low humidity. The peak value of photosynthetic available radiation (PARi) was 1 454 μmol·m-2·s-1, and the minimum and average values were 111 μmol·m-2·s-1and 938.889 6 μmol·m-2·s-1, respectively. Air temperature and sunlight intensity reached the highest values during 1 p.m. to 4 p.m. Net photosynthetic rate (Pn) of Xinyu increased stably before 11 a.m. and there was a midday depression during 11 a.m. to 2 p.m. The minimum value of Pn appeared at noon (2.77 μmol·m-2·s-1). It was concluded that as a new grape cultivar, “Xinyu” could withstand extreme climate conditions in Turpan.  相似文献   

19.
Leaf is one of the most important organs of soybean.The modeling of soybean leaf structure is useful to research of leaf function.The paper discussed it from two aspects that were distilling method of leaf profile and establishing method of leaf simulation model.It put forward basic method of soybean leaf digital process,and successfully established simulation model of soybean leaf structure based on L-system.It also solved a critical problem in the process of establishing soybean growth simulation model.And the research had guiding significance to establishment of soybean plant model.  相似文献   

20.
Consumers are bombarded with labels and claims that are intended to address their concerns about how food products are produced, processed, and regulated. Among those are the natural or all-natural claims and the certified organic label. In this study, two focus groups were conducted to explore consumers’ attitudes toward all-natural and organic pork and to gather their reactions to the USDA organic standards for meat, and the policy for natural claims. Results indicated that participants had positive associations with the terms “organic” and “all-natural” with exceptions regarding the trustworthiness of all-natural claims. Participants perceived the “no” labeling theme (no antibiotics, no hormones, no chemicals, etc.) often coupled with the all-natural label on pork products as identifying potential health and animal welfare risks. In response to the USDA standards and policies for labeling pork products as organic or all-natural, participants expressed confusion and had many unanswered questions.  相似文献   

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