首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Olive oil, a traditional food product with thousands of years of history, is continually evolving toward a more competitive global market. Being one of the most studied foods across different disciplines, olive oil still needs intensive research activity to face some vulnerabilities and challenges. This perspective describes some of them and shows a vision of research on olive oil for the near future, bringing together those aspects that are more relevant for better understanding and protection of this edible oil. To accomplish the most urgent challenges, some possible strategies are outlined, taking advantage of the latest analytical advances, considering six areas: (i) olive growing; (ii) processing, byproduct, and environmental issues; (iii) virgin olive oil sensory quality; (iv) purity, authentication, and traceability; (v) health and nutrition; (vi) consumers. The coming research, besides achieving those challenges, would increase the understanding of some aspects that are still the subject of debate and controversy among scientists focused on olive oil.  相似文献   

2.
土壤多样性研究趋势与未来挑战   总被引:8,自引:0,他引:8  
根据2013年美国CRC出版的新著《土壤多样性(Pedodiversity)》的主要章节,结合文献综述了国际间土壤多样性研究的进展与现状,着重分析总结了土壤多样性的研究模式。首先,介绍了土壤多样性概念的提出和多样性的含义;然后,阐述土壤多样性分析的目的和方法论,涉及到多样性与土壤分类制、尺度与抽样强度等基本原则;进而,着重分析了当前土壤多样性研究的主要模式,包括威利斯曲线、土壤多样性与生物多样性、丰富度分布模型、多样性—面积的关系、多样性—时间的关系、多样性嵌套结构、多样性与土壤形成过程、多样性与景观变迁等;最后,指出由于城市的无序扩张和人口密集的工业区基础设施的建设等驱动力影响,使得土壤多样性遭到破坏,人类应该更多关注、加强对土壤圈和土壤多样性的保护。  相似文献   

3.
4.
OBJECTIVES: To describe the US public health nutrition workforce and its future social, biological and fiscal challenges. DESIGN: Literature review primarily for the four workforce surveys conducted since 1985 by the Association of State and Territorial Public Health Nutrition Directors. SETTING: The United States. SUBJECTS: Nutrition personnel working in governmental health agencies. The 1985 and 1987 subjects were personnel in full-time budgeted positions employed in governmental health agencies providing predominantly population-based services. In 1994 and 1999 subjects were both full-time and part-time, employed in or funded by governmental health agencies, and provided both direct-care and population-based services. RESULTS: The workforce primarily focuses on direct-care services for pregnant and breast-feeding women, infants and children. The US Department of Agriculture funds 81.7 % of full-time equivalent positions, primarily through the WIC Program (Special Supplemental Nutrition Program for Women, Infants, and Children). Of those personnel working in WIC, 45 % have at least 10 years of experience compared to over 65 % of the non-WIC workforce. Continuing education needs of the WIC and non-WIC workforces differ. The workforce is increasingly more racially/ethnically diverse and with 18.2 % speaking Spanish as a second language. CONCLUSIONS: The future workforce will need to focus on increasing its diversity and cultural competence, and likely will need to address retirement within leadership positions. Little is known about the workforce's capacity to address the needs of the elderly, emergency preparedness and behavioural interventions. Fiscal challenges will require evidence-based practice demonstrating both costs and impact. Little is known about the broader public health nutrition workforce beyond governmental health agencies.  相似文献   

5.
A high proportion of threatened and near-threatened species in the world now inhabit farmland. Although much data regarding the impact of agriculture on farmland biodiversity have been accumulated in Western countries, such information, particularly on the impact of rice cultivation, is fragmentary in other parts of the world and has rarely been disseminated internationally. Therefore, this paper aims to clarify what information has become available through earlier studies in Japan, where farmland mainly consists of rice paddy areas, and give directions for future studies about the impact of agriculture on farmland birds in Japan. This study made three notable observations. First, a review of earlier studies of farmland bird species in Japan uncovered some evidence of both increases (e.g., wildfowl and cranes) and declines (e.g., waders) in population size. Second, this paper closely examined case studies of two types of typical farmland birds: (1) geese and cranes foraging on crops and/or harvested remains of crops and (2) waders and egrets foraging on small organisms in farmland, not agricultural crops. This portion of the study identified some potential routes through which human activities in farmland affect bird species in Japan, and offered practical implications for conservation and management of these species supported by scientific data. Finally, based on the results of this review, three key tasks for future conservation studies and practices in Japanese farmland were suggested: (1) establishing quantitative indices based on monitoring surveys in farmland to track the population status, (2) collecting further evidence of the impact of agriculture, particularly on population-level responses by birds, and in a food-web context, and (3) applying evidence-based conservation to practice.  相似文献   

6.
7.
Biodiversity conservation issues are often contentious and complex. Polarized debates on the effectiveness of protected areas and role of people inside them, charismatic species as conservation foci, and on specific policy initiatives are common among Indian and global conservationists. We surveyed Indian conservationists about the conservation effectiveness of protected areas and charismatic species, as well as status of conservation and research efforts. We expected differences among people based on professional affiliation, and educational background. We examined participants’ opinions on conservation policies like Project Tiger and Elephant, the Forest Rights Act, and the Tiger Task Force Report. Participants ranked Indian research efforts as average, and identified a bias towards terrestrial species and ecosystems. Ninety-percent of participants considered reserves to be effective, many (61%) participants felt that the situation of people living inside reserves is unsustainable, and many (76%) felt the use of force to protect reserves from illegal human activities is acceptable. Classification and regression tree models for these questions suggested that non-academics were more likely than academics to agree with these positions. On the success of Project Tiger and Elephant, older participants were more likely to think these initiatives were a success. Many (63%) participants felt the Forest Rights Act needed revision, particularly if they had doctoral degrees. Sixty-two percent of participants did not think Tiger Task Force was effective. Overall, participants’ professional affiliation, age, and academic degree were important predictors of participants attitudes towards conservation initiatives.  相似文献   

8.
Genetic Resources and Crop Evolution - Crop breeding for abiotic stress tolerance entails introgression of stress tolerant genes into the cultivated types. With the augmentation in salt tolerance,...  相似文献   

9.
Tillage is defined here in a broad sense, including disturbance of the soil and crop residues, wheel traffic and sowing opportunities. In sub-tropical, semi-arid cropping areas in Australia, tillage systems have evolved from intensively tilled bare fallow systems, with high soil losses, to reduced and no tillage systems. In recent years, the use of controlled traffic has also increased. These conservation tillage systems are successful in reducing water erosion of soil and sediment-bound chemicals. Control of runoff of dissolved nutrients and weakly sorbed chemicals is less certain. Adoption of new practices appears to have been related to practical and economic considerations, and proved to be more profitable after a considerable period of research and development. However there are still challenges. One challenge is to ensure that systems that reduce soil erosion, which may involve greater use of chemicals, do not degrade water quality in streams. Another challenge is to ensure that systems that improve water entry do not increase drainage below the crop root zone, which would increase the risk of salinity. Better understanding of how tillage practices influence soil hydrology, runoff and erosion processes should lead to better tillage systems and enable better management of risks to water quality and soil health. Finally, the need to determine the effectiveness of in-field management practices in achieving stream water quality targets in large, multi-land use catchments will challenge our current knowledge base and the tools available.  相似文献   

10.

Sugarcane (Saccharum spp.) is a special crop plant that underwent anthropogenic evolution from a wild grass species to an important food, fodder, and energy crop. Unlike any other grass species which were selected for their kernels, sugarcane was selected for its high stem sucrose accumulation. Flowering in sugarcane is not favored since flowering diverts the stored sugar resources for the reproductive and developmental energy needs. Cultivars are vegetatively propagated and sugarcane breeding is still essentially focused on conventional methods, since the knowledge of sugarcane genetics has lagged that of other major crops. Cultivar improvement has been extremely challenging due to its polyploidy and aneuploidy nature derived from a few interspecific hybridizations between Saccharum officinarum and Saccharum spontaneum, revealing the coexistence of two distinct genome organization modes in the modern variety. Alongside implementation of modern agricultural techniques, generation of hybrid clones, transgenics and genome edited events will help to meet the ever-growing bioenergy needs. Additionally, there are two common biotechnological approaches to improve plant stress tolerance, which includes marker-assisted selection (MAS) and genetic transformation. During the past two decades, the use of molecular approaches has contributed greatly to a better understanding of the genetic and biochemical basis of plant stress-tolerance and in some cases, it led to the development of plants with enhanced tolerance to abiotic stress. Hence, this review mainly intends on the events that shaped the sugarcane as what it is now and what challenges ahead and measures taken to further improve its yield, production and maximize utilization to beat the growing demands.

  相似文献   

11.
This review focuses on some important and challenging aspects of soil extracellular enzyme research. We report on recent discoveries, identify key research needs and highlight the many opportunities offered by interactions with other microbial enzymologists. The biggest challenges are to understand how the chemical, physical and biological properties of soil affect enzyme production, diffusion, substrate turnover and the proportion of the product that is made available to the producer cells. Thus, the factors that regulate the synthesis and secretion of extracellular enzymes and their distribution after they are externalized are important topics, not only for soil enzymologists, but also in the broader context of microbial ecology. In addition, there are many uncertainties about the ways in which microbes and their extracellular enzymes overcome the generally destructive, inhibitory and competitive properties of the soil matrix, and the various strategies they adopt for effective substrate detection and utilization. The complexity of extracellular enzyme activities in depolymerising macromolecular organics is exemplified by lignocellulose degradation and how the many enzymes involved respond to structural diversity and changing nutrient availabilities. The impacts of climate change on microbes and their extracellular enzymes, although of profound importance, are not well understood but we suggest how they may be predicted, assessed and managed. We describe recent advances that allow for the manipulation of extracellular enzyme activities to facilitate bioremediation, carbon sequestration and plant growth promotion. We also contribute to the ongoing debate as to how to assay enzyme activities in soil and what the measurements tell us, in the context of both traditional methods and the newer techniques that are being developed and adopted. Finally, we offer our collective vision of the future of extracellular enzyme research: one that will depend on imaginative thinking as well as technological advances, and be built upon synergies between diverse disciplines.  相似文献   

12.
土壤优先流研究现状与发展趋势   总被引:8,自引:0,他引:8  
徐宗恒  徐则民  曹军尉  孟庆会 《土壤》2012,44(6):905-916
优先流是近年来针对土壤水运动所提出的术语,是土壤中水运动机制研究由均匀走向非均匀领域的标志,是指在土壤各向异性的情况下,水分和溶质在多重因素的共同作用下,沿着特定的路径向下发生非稳定渗流的现象.优先流是造成降雨型滑坡、泥石流等地质灾害以及地下水质污染、农业土壤中养分流失等现象的主要诱因之一,所以深入开展优先流的研究显得尤为重要.本文从优先流的界定出发,主要介绍回顾了优先流数学模型的发展和研究优先流所采用的技术手段和方法,最后总结并探讨了优先流研究中存在的问题和发展趋势.  相似文献   

13.
根据晋中地区农业环境污染的现状 ,针对性地提出了保护对策。  相似文献   

14.
The principles of modern pesticide residue chemistry were articulated in the 1950s. Early authors pointed out the advantages of systematizing and standardizing analytical methods for pesticides so that they could be widely practiced and the results could be reproduced from one laboratory to the next. The availability of improved methods has led to a much more complete understanding of pesticide behavior and fate in foods and the environment. Using methods based largely upon gas chromatography (GC) and high-performance liquid chromatography (HPLC) coupled increasingly with mass spectrometry (MS) and MS(n) as the detection tool, residues can be measured at parts per billion levels and below in a variety of food and environmental matrices. Development of efficient extraction and cleanup methods, techniques such as ELISA, efficient sample preparation techniques such as QuEChERS, and automated laboratory and field instrumentation has also contributed to the tools available for use in modern pesticide residue analysis. As a result, great strides have been made in improving food and worker safety and in understanding environmental behavior and fate of pesticides. There are many challenges remaining in the field of pesticide residue chemistry that will continue to stimulate analytical chemists. New chemistries are emerging, often patterned on complex natural products. Analyzing for the parent chemicals and potentially multiple breakdown products will require analytical ingenuity. The development of more sensitive bioassays and knowledge of unintended side effects will challenge residue chemistry as well, as in the case of following the fate of environmental endocrine disruptors associated with some pesticides as well as nonpesticide contaminants from packaging materials and other familiar articles. Continued funding and other resources to ensure better training, international cooperation, and accelerated research and development activities will be a constant need in pesticide residue chemistry as it is for all areas of science that aim to mitigate or eliminate contaminants that can affect human and environmental health and safety.  相似文献   

15.
Being part of a highly dynamic system, contaminated sediments are especially in need of an integrated management approach. Due to change in importance from source to diffuse pollution and the variety of chemical substances in the environ-ment, different scientific fields need to cooperate and incorpo-rate their data in a common risk assessment scheme. Public perception of risk that is associated with sediments and with chemical data is low while the acceptance of ecotoxico-logical data with decision makers is often missing. A growing demand of the public to be involved in decision processes and informed about environmental problems demands a change of methods and concepts in the future. Necessity of an integration of risk assessment and management procedures has been suggested in order to increase the efficiency of the process and the early involvement of public concern. As the confidence in experts’ opinions decreases, a strong need for communication with and transparency for all involved parties arises.  相似文献   

16.
Fouling of complex food components onto food-processing materials affects food quality, food safety, and operating efficiency. Developments in nonfouling and fouling-release materials for biomedical and marine applications enable the potential for adaptation to food applications; however, challenges remain. The purpose of this review is to present different strategies to prevent fouling and/or facilitate foulant removal with a critical point of view for an application of such materials on food-processing surfaces. Nonfouling, self-cleaning, and amphiphilic materials are reviewed, including an explanation of the mechanism of action, as well as inherent limitations of each technology. Perspectives on future research directions for the design of food processing surfaces with antifouling and/or fouling release properties are provided.  相似文献   

17.
Effective plant protection practices and use of chemical pesticides are a prerequisite for maintaining yields of sufficient quality and quantity in conventional agriculture today. Despite regulatory efforts to ensure safe use, reports have indicated that residual amounts of pesticides and their metabolites occur in surface and ground water and may have non-target effects on aquatic organisms. The objective of the present study was to identify environmental challenges of pesticide use in the northern climate by evaluating long-term pesticide monitoring data compiled by the Norwegian Agricultural Environmental Monitoring Programme. Pesticide use data and pesticide concentrations measured in stream water from six small agricultural catchments in Norway were analysed. Observed trends in pesticide detection frequencies, measured concentrations and cumulative risk from the six monitoring sites were compared. The results demonstrated the need for continued focus on the herbicides metribuzin and aclonifen, and potential concerns regarding use of the fungicide prothioconazole and the insecticide imidacloprid. The six monitoring sites represented the diversity of intensively cropped areas in Norway and differed with respect to estimated cumulative risk. Vegetable and potato cropping areas showed not only the highest level of total environmental risk, but also a statistically significant decreasing trend over the monitoring period. Cereal cropping areas exhibited no statistically significant time-dependent trends in the studied parameters but did show an increase in fungicide use that requires continued attention. The need for risk assessment of mixture toxicity effects and improved monitoring strategy is also discussed. In conclusion, the present results imply that the current global focus on multiple stressors and mixture toxicity of pesticides in stream water is equally relevant in cold climatic conditions.  相似文献   

18.
19.
20.
The Baltic Sea is one of the most polluted sea areas in the world. Except for different local pollution sources, the overall environmental problem is eutrophication. The eutrophic situation is caused by increased external load of nutrients during decades. Since nitrogen (N) is generally considered the main limiting nutrient for primary production in the Baltic Sea, the countries within the Baltic Sea drainage basin have agreed to reduce the anthropogenic waterborne input of N by 50% between 1987 and 1995. Furthermore, N emissions to the atmosphere are to be frozen at the level that existed at the end of the 1980s. A number of countries have also declared their intention to reduce N emissions to the atmosphere by 30% between 1980 and 1998. Presently, the annual N load to the Baltic Sea totals 1,409,000 tonnes, of which 980,000 tonnes (69%) are waterborne discharges (rivers, point and non-point sources), and 134,000 tonnes (10%) are caused by N2 fixation. The rest, 296,000 tonnes (21%) is atmospheric deposition on the sea surface. Some 60% of the atmospheric deposition is caused by emissions from sources in the drainage area and the rest is emissions from areas outside the drainage area. The highest acceptable future N load to the Baltic Sea is estimated at 600,000 tonnes/year. This means a necessary reduction of 57%, compared to the present load. Therefore, comprehensive load reductions must be conducted from anthropogenic sources, e.g. agriculture, forest and forestry, industry, and municipal sewage treatment plants and rural living. The atmospheric N deposition must be reduced by almost 40%, and the measures must focus on emission reductions in traffic, combustion, and agriculture.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号