微生物生物技术在现代农业体系中的生态意义

在农业生态系统中,微生物有利于生态系统中养分循环,增加植物抗性,提高农作物对营养吸收,并改善土壤结构。保护微生物资源,维持微生物多样性,需要对微生物多样性进行评价。目前微生物多样性评价方法主要包括传统的微生物培养法、生物标记法、BIOLOG微平板分析方法和分子生物技术。在现代农业的进程中,利用微生物生物技术研制的微生物农药、微生物化肥、微生物饲料、微生物食品和微生物能源在农业上已开始应用。在未来,微生物生物技术在新品种培育、解决能源短缺和减少环境污染方面将会发挥越来越重要的作用。     

INTERCROPPING: FEED MORE PEOPLE AND BUILD MORE SUSTAINABLE AGROECOSYSTEMS

• Intercropping is a useful practice when agricultural sustainability is emphasized.• We integrate biodiversity-ecosystem functioning and intercropping.• Intercropping optimizes ecosystem services such as stabilizing yield and reducing use of chemicals.• Intercropping benefits are attributed partly to complementarity and selection effects.• Application of ecological principles is key to sustainable agricultural development.Intercropping is a traditional farming system that increases crop diversity to strengthen agroecosystem functions while decreasing chemical inputs and minimizing negative environmental effects of crop production. Intercropping is currently considerable interest because of its importance in sustainable agriculture. Here, we synthesize the factors that make intercropping a sustainable means of food production by integrating biodiversity of natural ecosystems and crop diversity. In addition to well-known yield increases, intercropping can also increase yield stability over the long term and increase systemic resistance to plant diseases, pests and other unfavorable factors (e.g. nutrient deficiencies). The efficient use of resources can save mineral fertilizer inputs, reduce environmental pollution risks and greenhouse gas emissions caused by agriculture, thus mitigating global climate change. Intercropping potentially increases above- and below-ground biodiversity of various taxa at field scale, consequently it enhances ecosystem services. Complementarity and selection effects allow a better understanding the mechanisms behind enhanced ecosystem functioning. The development of mechanization is essential for large-scale application of intercropping. Agroecosystem multifunctionality and soil health should be priority topics in future research on intercropping.     

农业生态系统健康评估方法研究概况

各种胁迫因子对农业生态系统可能造成极大危害，有时甚至会带来不可逆转的崩溃，因此保护农业生态系统的健康十分重要。本文从农业生态系统健康学说的形成与发展、危及农业生态系统健康的胁迫因子、农业生态系统健康的评价方法和指标等几个方面综述了农业生态系统健康学的研究概况，事实上，农业生态系统健康与可持续农业 是相一致的，目前对农业生态系统健康的评估还没有一套可靠而统一的标准，常用的方法主要有生态系统失调综合症的诊断、系统缓冲力和持续性的评估以及生态网络评估等，最后讨论了尚待进一步研究的内容，并指出当前我国在发展可持续农业上需要注意的几个方面。     

SUSTAINABLE NITROGEN MANAGEMENT IN AUSTRALIAN AGROECOSYSTEMS: CHALLENGES AND OPPORTUNITIES

● There is huge potential for improvement of nitrogen management in Australia. ● N management should incorporate environmental, social and economic sustainability. ● Agronomic, ecological and socioeconomic approaches and efforts are needed. Nitrogen is an essential nutrient that supports life, but excess N in the human-environment system causes multiple adverse effects from the local to the global scale. Sustainable N management in agroecosystems, therefore, has become more and more critical to address the increasing concern over food security, environmental quality and climate change. Australia is facing a serious challenge for sustainable N management due to its emission-intensive lifestyle (high level of animal-source foods and fossil fuels consumption) and its diversity of agricultural production systems, from extensive rainfed grain systems with mining of soil N to intensive crop and animal production systems with excessive use of N. This paper reviews the major challenges and future opportunities for making Australian agrifood systems more sustainable, less polluting and more profitable.     

Information services for European pork chains - Closing gaps in information infrastructures

Several global developments (e.g. diminishing production resources, growing demand for bio-energy) and numerous sector-wide crises (e.g. BSE, swine fever, dioxin) have led to a changing attitude of society towards the consequences of the food systems activities for social, economic and environmental issues, captured in the term of sustainability. Consumers in their role as final customers, and as a consequence also enterprises within agri-food supply chains, show increasing interest in the characteristics of food, and in turn, on the availability of related information and guarantees. Enterprises in agri-food supply chains are facing new expectations and are seeking to communicate social, economic and environmental performance of their business to customers within their supply chain and to consumers. New solutions for determination and communication of sustainability are needed for the agri-food sector, covering single aspects of sustainability as well as sustainability in a broader sense, including social, economic and environmental issues. Integrated, computer-based information services, since they are mainly building on existing systems, provide flexible solutions for enterprises to measure and evaluate sustainability of products throughout agri-food supply chains. Gained information on product characteristics might be used for decision support within enterprises as well as for communication of sustainable practices to customers and consumers, resulting in increased competitiveness of enterprises, supply chains and the sector by satisfying customers’ and consumers’ demands for information on the sustainability of a product. The present paper introduces a framework for developing information services for European pork chains using the three selected information domains food safety (representing social sustainability), quality (representing economic sustainability) and global warming potential (representing environmental sustainability). Resulting information models give an aggregated overview on information availability and exchange in European pork chains, additional information demands of possible service users and deficiencies in the existing information infrastructures. The paper supports different stakeholders involved in agri-food production, such as service developers, enterprise decision makers and management consultants, in developing enterprise- and chain-specific solutions which meet customers’ and consumers’ demands by providing appropriate sustainability information and guarantees.     

The future of seawater desalination: energy, technology, and the environment

In recent years, numerous large-scale seawater desalination plants have been built in water-stressed countries to augment available water resources, and construction of new desalination plants is expected to increase in the near future. Despite major advancements in desalination technologies, seawater desalination is still more energy intensive compared to conventional technologies for the treatment of fresh water. There are also concerns about the potential environmental impacts of large-scale seawater desalination plants. Here, we review the possible reductions in energy demand by state-of-the-art seawater desalination technologies, the potential role of advanced materials and innovative technologies in improving performance, and the sustainability of desalination as a technological solution to global water shortages.     

黄淮海地区农业生态经济系统能值分析

为了更好地评价黄淮海地区农业生态经济系统的运行特征和可持续发展状况,本文利用能值分析理论通过构建评估指标体系.对黄淮海地区农业生态系统的能值投入产出状况、环境承载情况和生态系统运行效果进行了定量分析.结果表明黄淮海地区农业生态系统能值产出率相对较高,整体运行状况较好,具有较强市场竞争力,环境承受能力较强和可持续发展能力较强,但仍处于石油农业发展阶段,其化肥、农药和地膜等工业辅助能值大幅度增加,其发展可持续性有一定下降趋势,造成对生态环境的较大压力应引起关注.为促进黄淮海地区农业的可持续发展,应调整其能值投入和产出结构,加大农业科技的研究和推广力度,适"-3降低以化肥为代表的工业辅助能投入,改变化工农业生产模式,走农业可持续发展的道路.     

Global change and the ecology of cities

Urban areas are hot spots that drive environmental change at multiple scales. Material demands of production and human consumption alter land use and cover, biodiversity, and hydrosystems locally to regionally, and urban waste discharge affects local to global biogeochemical cycles and climate. For urbanites, however, global environmental changes are swamped by dramatic changes in the local environment. Urban ecology integrates natural and social sciences to study these radically altered local environments and their regional and global effects. Cities themselves present both the problems and solutions to sustainability challenges of an increasingly urbanized world.     

现代农业生产力计量的一种新思路

农业生产力的计量方法直接决定着人类对农业生态系统的价值评估,进而决定生产者对生产方式的选择。过去的一个世纪内,农业的功能与属性都已经发生了根本性的变化,尤其是其对自然资本的消耗和生态环境的影响已成为全球可持续发展的重要支配力量。然而当前沿用的农业生产力计量方法却反映不出这些变化了的特征和需要．以致于严重削弱了现时农业生产力也使损害了农业可持续发展能力的不当生产方式被肯定、支持和鼓励。本文梳理了农业生产属性演变和生产力计量方法发展的脉络,提出用农业生态系统生产力概念和方法体系来计量农业生产力的设想。     

耕作措施对双季稻田土壤碳及有机碳储量的影响

针对不同耕作措施对双季稻田的固碳效应和固碳潜力问题,选择湖南省宁乡县的双季稻区试验点进行了有机碳、活性有机碳以及耕层有机碳储量的研究,以期为制定适合于稻田条件下的合理耕作方式提供理论依据。结果表明,耕作措施和秸秆还田对有机碳(SOC)和活性有机碳(AOC)含量均产生不同程度的影响。免耕处理下,有机碳和活性有机碳含量皆随土壤深度的增加而减少,土壤0～5cm的SOC和AOC的含量最高,且与其他层次达到显著性差异水平(P<0.05),具有明显的表层富集现象。与免耕相比,旋耕和翻耕则更利于5～10cm和10～20cm土层的有机碳和活性有机碳的积累。比较秸秆还田对SOC和AOC的影响表明,秸秆还田有效地提高了0～10cm有机碳含量,但对10～20cm并未产生显著影响,秸秆的输入并未增加土壤活性有机碳的含量。采用等质量方法计算了耕层土壤有机碳储量,结果显示旋耕秸秆还田使有机碳储量明显增加,而免耕只增加了土壤0～5cm和5～10cm土层有机碳储量,10～20cm有机碳储量有所降低,但耕作措施对有机碳储量的长效作用还有待于进一步研究。     

Environmental justice and care: critical emancipatory contributions to sustainability discourse

Sustainability has become a powerful discourse, guiding the efforts of various stakeholders to find strategies for dealing with current and future social-ecological crises. To overcome the latter, we argue that sustainability discourse needs to be based on a critical-emancipatory conceptualization. Therefore, we engage two such approaches—environmental justice approaches informed by a plural understanding of justice and feminist political economy ones focusing on care—and their analytical potential for productive critique of normative assumptions in the dominant sustainability discourse. Both of these approaches highlight aspects of sustainability that are particularly relevant today. First, although sustainable development was conceptualized from the outset based upon a twofold notion of justice (intra- and intergenerational), the integration of justice in the dominant sustainability discourse and praxis often manifests merely as a normative aspiration. Meanwhile, the environmental justice and care approaches offer conceptualizations of justice that can act as a powerful lever and as transformation-strategy. Second, the dominant sustainability discourse largely remains within a neoliberal economic framework that continues to promote economic growth as the means to reach prosperity while neglecting the bases of every economy: care work and nature. Its focus lies solely on paid work and the market economy. By integrating (a) social and ecological ‘reproductivity’ (unpaid care and subsistence work as well as nature) and (b) democratic processes for just distribution of environmental burdens and benefits, as well as participatory equity in relevant decision making, feminist political economy and environmental justice approaches offer substantial strategies towards building humane, just and caring societies.     

基于能值的农业生态经济系统动态分析——以河北省武安市为例

采用能值分析的方法,对农业生态经济系统的投入产出进行分析,并选取了净能值产出率、能值投资率、环境负载率、可持续发展指数、系统生产优势度5个指标进行评价。结果表明:武安市能值投入与产出均处于上升态势,能值投资率不断上升,但净能值产出率降低,农产品的价格竞争优势逐步丧失;同时随着不可更新工业辅助能的加大,环境压力也在日益增加。在未来的农业发展中,要更加注重农业发展与生态环境的协调,实现农业可持续发展。     

Normalised,human-centric discourses of meat and animals in climate change,sustainability and food security literature

The large-scale, intensive production of meat and other animal products, also known as the animal-industrial complex, is our largest food system in terms of global land use and contribution to environmental degradation. Despite the environmental impact of the meat industry, in much of the policy literature on climate and environmental change, sustainability and food security, meat continues to be included as part of a sustainable food future. In this paper, I present outcomes of a discourse analysis undertaken on a selection of key major international and Australian reports. After highlighting common themes in the ways that meat and animals are discussed, I draw on the animal studies literature to critically analyse the assumptions underpinning such policy documents. My analysis illustrates that animals are effectively de-animated and rendered invisible in these bodies of literature by being either aggregated—as livestock, units of production and resources, or materialised—as meat and protein. These discursive frames reflect implicit understandings of meat as necessary to human survival and animals as a natural human resource. A critical examination of these understandings illustrates their dual capacity to normalise and encourage the continuation of activities known to be seriously harming the environment, climate and human health, while at the same time obstructing and even denigrating alternative, less harmful approaches to food. In response, I offer some conceptual and analytical modifications that can be easily adopted by researchers on climate change, sustainability and food security with the aim of challenging dominant discourses on meat and animals.     

The geological record of ocean acidification

Ocean acidification may have severe consequences for marine ecosystems; however, assessing its future impact is difficult because laboratory experiments and field observations are limited by their reduced ecologic complexity and sample period, respectively. In contrast, the geological record contains long-term evidence for a variety of global environmental perturbations, including ocean acidification plus their associated biotic responses. We review events exhibiting evidence for elevated atmospheric CO(2), global warming, and ocean acidification over the past ~300 million years of Earth's history, some with contemporaneous extinction or evolutionary turnover among marine calcifiers. Although similarities exist, no past event perfectly parallels future projections in terms of disrupting the balance of ocean carbonate chemistry-a consequence of the unprecedented rapidity of CO(2) release currently taking place.     

Improved crop protection and biodiversity of the agroecosystem by reduced tillage in rice paddy fields in southern China

Agricultural sustainability has benefited from the broad adoption of conservation agriculture (CA) practices for decades, in which the reduction of mechanical disturbances to soil (also known as reduced tillage, RT) is one of the most essential principles for CA implementation. Many studies have recommended the advantages of CA practices in the promotion of biodiversity, but the integrated impacts on crop productivity and biodiversity remain unclear. Since CA has been applied in rice production in the subtropical area of southern China for several years, the effects of CA, particularly the RT methods, need to be evaluated for the local and long-term adoption. In this study, we established an integrated network to illustrate how the reduction of tillage intensity influenced organisms including invertebrates (such as rice pests and their predators), pathogens and weeds, and then led to an impact on rice yield. The two-year study demonstrated that major rice pests, such as rice planthoppers, stem borers and apple snails, were effectively controlled by RT practice. Similarly, the occurrence of common diseases declined with less tillage. Compared to the conventional tillage (CT) treatment, the density of weeds in paddy fields deceased significantly in the RT treatment. In addition, the diversity and richness of pest predators increased remarkably in paddy fields where either reduced or no tillage was applied, which highlighted the significance of a CA strategy for the promotion of biodiversity in the agroecosystem. More importantly, the rice yield gradually increased after the two-year reduction of tillage. Taken together, our results suggest that the reduction of tillage intensity is beneficial for the protection of rice crops from various pests, and facilitates the sustainability of the agroecosystem and rice yield, which provides a solid basis and novel insights for the establishment of sustainable agroecosystems by CA-related practices in rice production in southern China.     

Utilizing a social ethic toward the environment in assessing genetically engineered insect-resistance in trees

Social policies are used to regulate how members of a society interact and share resources. If we expand our sense of community to include the ecosystem of which we are a part, we begin to develop an ethical obligation to this broader community. This ethic recognizes that the environment has intrinsic value, and each of us, as members of society, are ethically bound to preserve its sustainability. In assessing the environmental risks of new agricultural methods and technologies, society should not freely trade economic gains for ecological damage, but rather seek practices that are compatible with ecosystem health. This approach is used to evaluate the environmental risks associated with genetically engineered insect-resistant trees. The use of insect-resistant trees is a biologically based pest control strategy that has several advantages over pesticide use. However, the use of genetically engineered trees presents particular ecological concerns because the trees are long lived and often are not highly domesticated. The main environmental concerns reviewed include: (1) adaptation of pests to the trees, leading to a non-sustainable agricultural practice, (2) transgenic trees producing environmental toxins, (3) insect resistance enhancing the invasiveness of the tree, causing it to become weedy or invade wild habitats, and (4) transfer of the transgene to wild or feral relatives of the tree, possibly increasing the invasiveness of weeds or wild plants. Some methods are available to offset these risks; however, the environmental risks associated with this technology have been poorly researched and need to be more clearly identified so that when we evaluate the risks, it is based on the best information obtainable. To fulfil an ethical obligation to the environment, public policies and government regulations are needed to preserve the sustainability of both the environment and the future of our production systems. A better understanding of both the ecological issues and of genetic engineering in general are needed on the part of citizens and policy makers alike to ensure that sound environmental decisions are made. Otherwise, the environmental benefits of this technology, mainly decreasing the use of more toxic pesticides in tree crops and forests, will either be lost or traded for other environmental hazards.     

Cultivating values: environmental values and sense of place as correlates of sustainable agricultural practices

To assess whether and how environmental values and sense of place relate to sustainable farming practices, we conducted a study in South Kona, Hawaii, addressing environmental values, sense of place, and farm sustainability in five categories: environmental health, community engagement and food security, culture and history, education and research, and economics. We found that the sense of place and environmental values indexes showed significant correlation to each category of sustainability in both independent linear regressions and multivariate regression. In total, sense of place explained a larger share of the overall farm performance. However, each indicator showed relative strengths; environmental values showed significantly higher correlation to environmental and educational practices. Furthermore the scales were complimentary, and the use of both scales greatly improved prediction of good farming practices from a multiple-impact perspective. With implications for community and environmental impacts, results suggest that a more comprehensive view of farmers’ environmental values and place connections may help illuminate individual farmers’ decisions and sustainability-related practices.     

CONSTRUCTION OF AN INDEX SYSTEM FOR SUSTAINABILITY ASSESSMENT IN SMALLHOLDER FARMING SYSTEMS

● A five-step process for quantifying smallholder farming system sustainability is proposed. ● Definition of system boundary, functional unit, and indicators depends on research issues. ● Weighting, conversion, and aggregation methods tightly relates to the validity of assessment results. Smallholder farming systems are important for global food security, but these faces multiple environmental challenges hindering sustainable development. Although sustainable smallholder agriculture issues have been widely discussed and addressed by scientists globally, harmonized approaches in evaluating sustainability are still lacking. This paper proposes a five-step process for constructing a sustainability assessment method for smallholder farming systems, namely definition of system boundary, indicator selection, indicator weighting, indicator conversion, and indicator aggregation. The paper summarizes the state-of-art progresses in agricultural sustainability assessment at different stages, and systematically discussed the benefits and limitations of weighting and aggregation methods. Overall, this evaluation process should be useful by providing rational and comprehensive results for quantifying the sustainability of smallholder farming systems, and will contribute to practice by providing decision-makers with directions for improving sustainable strategies.     

退耕还林项目对陕北地区自然与社会的影响

 【方法】应用试验监测与社会调查相结合的方法，研究和报告中国退耕还林项目对区域生态景观系统快速变化的影响。【目的】为生态修复政策对自然和社会的影响提供可借鉴的研究案例。【结果】中国陕北地区实施退耕还林政策以来，地表植被覆盖度由1998年的34.6%增至2005年的49.2%；但是干旱半干旱生态脆弱区大规模的人工造林可诱发严重的水资源短缺、导致人工林地植被覆盖度减小、以及对植物种类多样性的负面影响，相对而言，封山禁牧对生态脆弱区的植被修复效果最好；生态政策与项目的有效实施离不开公众的大力支持，不幸的是88.8%的居民希望获得政府对农业生产项目的支持而不是开展植树种草。【结论】调查结果表明，退耕还林项目恢复的植被在项目结束后有可能被重新开垦为农田，该项目获得的环境成果面临再次毁灭的风险。因此，把发展经济、改善教育与环境修复有机地结合起来，是环境修复项目成功的重要保证。     

Not just what, but how: Creating agricultural sustainability and food security by changing Canada's agricultural policy making process

Agriculture has been enormously productive in recent decades. The main problem is that fragmentation of issues, knowledge, and responsibilities has hidden the costs associated with this success. These are mainly environmental, social, and health costs, which have been assigned to other ministries, with their own histories unconnected to agriculture. Now that agricultural policy has achieved its success, its costs are becoming apparent. The current system is preoccupied with traditional views of competitiveness and efficiency. Policies, programs, and regulations are organized to support specific commodities, not farming and food systems. Responsibilities are extremely fragmented and frequently uncoordinated. In this environment, the focus on nourishment, food security, and environmental sustainability is subordinated to economic issues.The future lies in reorienting agricultural policy away from maximum production and towards sustainability. We propose a major transformation of the policy making apparatus in order to shift the focus of the system towards nourishment, food security, and sustainability. A new policy making system must be built on the themes of: integrated responsibilities and activities; emphasis on macro-policy; transdisciplinary policy development; proximity of policy makers to the diverse groups affected by problems needing resolution; food systems policy.The design principles for such a new system are taken from the theory of food security and ecology. Using these principles, we design a new provincial department of food and food security, and test this design with two case studies.