丛枝菌根真菌应用技术研究进展

丛枝菌根(AM)共生体系能够改善植物营养状况,增强植物对各种逆境胁迫的耐受性,其在农业和生态环境方面的应用得到广泛关注.近年来,在AM真菌(AMF)应用技术和田间试验方面取得了许多重要成果.本文在介绍AMF种质资源库、商业化菌剂生产及相关专利申报情况的基础上,结合实例从菌剂生产、接种技术、接种效应影响因素等方面综述了AMF应用技术的理论与实践,包括国内外近年来菌根技术在农业、园艺、生态修复等方面的应用,最后提出尚待系统深入研究的 AMF应用领域中的关键科学和技术问题,旨在为菌根技术的发展和推广应用提供参考.     

再论可持续性科学: 新形势与新机遇

近10年来,可持续性科学蓬勃发展,已成为21世纪全球普遍关注的一个重要的新科学领域.然而,在大力提倡可持续发展和生态文明建设的中国,可持续性科学尚未引起科学家和实践者的足够重视.为促进可持续性科学在中国的发展,2014年邬建国等曾撰文介绍什么是可持续性科学.本文进一步探讨了这一问题,并补充阐述了可持续性科学与可持续发展研究的关系、可持续性科学的科学范式及其8个基本论题.基于对可持续性科学发展动态的分析,作者认为,一方面,可持续性科学已进入系统推进的成熟发展期;另一方面,虽然我国可持续发展研究、实践与教育的热情高涨,但在可持续性科学领域起步较晚,落后于主要发达国家和南非.为此,本文在文献综述的基础上,提出促进中国发展可持续性科学的“三位一体”策略:一是“请进来”以服务中国实践;二是“走出去”以贡献中国智慧;三是“中西医结合”以引领学科发展.     

基于扩展耗模型的可持续发展水平区域空间差异——以中国31个省市为数据源

将区域作为一个以人类生产和消费为中心的社会-经济-自然复合生态系统,构建了一种基于生物物理视角的生态热力学方法,从整体角度对区域的可持续发展水平进行定量评价。该方法囊括了维持复合生态系统运转过程中的自然资源投入、人力资源投入和环境污染损害成本投入等三种要素,完善了可持续发展评价以及绿色GDP核算中人力资源投入和环境成本的价值体现。然后以我国为例,核算了我国31个省市2006—2015年间可持续发展水平的时间动态,并以各省为边界,计算了2015年的区域可持续发展水平差异。计算结果显示:(1)十年间,我国整体上的可持续发展水平在逐步提高,能反映出我国生产率水平的提高和资源利用效率的提高;(2)从要素投入看,自然资源投入仍然占主要,但比例在逐渐降低。环境成本投入比例呈逐步降低趋势,说明环境保护取得了成效。另外,在2010年后,人力资源投入比例增加很快,反映了我国经济发展中劳动力成本上升明显。(3)各省市的计算结果差异较大,在不考虑区域间进出口的情况下,从GDP产出角度,北京的可持续发展水平最高,西藏最低。通过将本文的评价结果与绿色发展指数的评价结果进行比较,发现具有较好的一致性。建立的方法框架是对能值分析方法的扩展和完善,在今后的研究中,还需要继续对该方法框架中没有考虑全面的因素加以考虑,以便于更全面客观地反映区域的可持续发展水平。     

Opportunities and Challenges of Plant Bioactive Compounds for Food and Agricultural-Related Areas

The growing development of biological products highlights the social and environmental responsibility that several industrial companies are facing in recent years. In this context, the advancement of bioprocessing as an alternative for exploring the potential of ecologically based products, especially in biofuels, food, and agro-industrial business, exposes the rational efficiency of the application of renewable sources in different industrial segments. Industries strongly associated with food production concentrate large amounts of wastes rich in bioactive compounds. A range of highly effective technologies has been highly explored to recover large concentrations of prominent compounds present in these materials. The advances in this scenario assurance value addition to these by-products, in addition to highlighting their various technological applications, considering the biorefinery and ecologically based production concepts. Accordingly, this review article described a detailed and systematic approach to the importance of using bioactive compounds and exploring the main sources of these elements. Also, some recent and innovative research that has achieved encouraging results was highlighted. Furthermore, the study included the main extraction technologies that have been investigated as a strategy of prospecting the application of bioactive compounds and optimizing the processes for obtaining natural compounds from plant sources. Finally, future outlooks were presented to contribute to the innovative opportunities and applicability of highly promising technologies and manipulations of bioactive compounds from a range of perspectives.     

Effects of biodiversity in agricultural landscapes on the protective microbiome of insects – a review

Symbiotic bacteria in herbivorous insects can have strong beneficial impacts on their host's survival, including conferring resistance to natural enemies such as parasitoid wasps or pathogens, while also imposing energetic costs on the host, resulting in cost‐benefit trade‐offs. Whether these trade‐offs favour the hosting of symbionts depends on the growth environment of the herbivore. Long‐term experimental grassland studies have shown that increasing plant species richness leads to an increased diversity of associated herbivores and their natural enemies. Such a change in natural enemy diversity, related to changes in plant diversity, could also drive changes in the community of symbionts hosted by the herbivorous insects. Aphids are one model system for studying symbionts in insects, and effects of host‐plant species and diversity on aphid‐symbiont interactions have been documented. Yet, we still understand little of the mechanisms underlying such effects. We review the current state of knowledge of how biodiversity can impact aphid‐symbiont communities and the underlying drivers. Then, we discuss this in the framework of sustainable agriculture, where increased plant biodiversity, in the form of wildflower strips, is used to recruit natural enemies to crop fields for their pest control services. Although aphid symbionts have the potential to reduce biological control effectiveness through conferring protection for the host insect, we discuss how increasing plant and natural enemy biodiversity can mitigate these effects and identify future research opportunities. Understanding how to promote beneficial interactions in ecological systems can help in the development of more sustainable agricultural management strategies.     

Solid Biomass Climate Change Interventions Examined in a Context of Inherent Safety,Media Shifting,and Emerging Risks

ABSTRACT

This article examines recent evidence from Denmark and abroad regarding climate change projects that aim to reduce global carbon dioxide emissions by converting coal-fired thermal power plants to solid biomass fuel. The article argues that projects appear to be pursued narrow-mindedly with insufficient attention paid to safety and points to evidence of media shifting—that the “resolution” of a problem within the environmental domain creates a new problem in the workplace safety domain. From the perspective of inherent safety the article argues that the conversion is a step in the wrong direction as a low risk fuel is substituted for a less safe one. Because of rapid scale-up and handling of unprecedented quantities, solid biomass qualify as an emerging risk for which proper control strategies have yet to be developed. The article finally argues that the tendency to prioritize environmental benefits over safety concerns seems to run deep and not confined to the realm of only solid biomass. Danish environmental ambitions are very high and the costs to society of introducing solid biomass fuels are breathtaking. In this setting, the general failure to address safety risks appears particularly disheartening.     

Decoupling Analysis of the Environmental Mountain—with Case Studies from China

The resource‐development trajectory of developed countries after the Industrial Revolution of the eighteenth and nineteenth centuries can be portrayed as an “environmental mountain” (EM). It is important for developing countries to decouple their resource use from economic growth and tunnel through the EM. In this study, we embedded the decoupling indicators for resource use and waste emissions into EM curves to quantify China's progress in tunneling through the EM over a specific time period. Five case studies regarding the conditions required for decoupling energy consumption, crude steel production, cement production, CO₂ emissions, and SO₂ emissions from economic growth in China were conducted. The results indicated that during 1985–2010 the trajectories of energy consumption, and CO₂ and SO₂ emissions in China met the requirements for tunneling through the EM, but the trajectories of cement and steel production did not. Based on these results, suggestions regarding China's environmental policies are provided to enable the country to tunnel through the EM.     

Nitrogen yield advantage from grass–legume mixtures is robust over a wide range of legume proportions and environmental conditions

Current challenges to global food security require sustainable intensification of agriculture through initiatives that include more efficient use of nitrogen (N), increased protein self‐sufficiency through homegrown crops, and reduced N losses to the environment. Such challenges were addressed in a continental‐scale field experiment conducted over 3 years, in which the amount of total nitrogen yield (N_tot) and the gain of N yield in mixtures as compared to grass monocultures (N_gainmix) was quantified from four‐species grass–legume stands with greatly varying legume proportions. Stands consisted of monocultures and mixtures of two N₂‐fixing legumes and two nonfixing grasses. The amount of N_tot of mixtures was significantly greater (P ≤ 0.05) than that of grass monocultures at the majority of evaluated sites in all 3 years. N_tot and thus N_gainmix increased with increasing legume proportion up to one‐third of legumes. With higher legume percentages, N_tot and N_gainmix did not continue to increase. Thus, across sites and years, mixtures with one‐third proportion of legumes attained ~95% of the maximum N_tot acquired by any stand and had 57% higher N_tot than grass monocultures. Realized legume proportion in stands and the relative N gain in mixture (N_gainmix/N_tot in mixture) were most severely impaired by minimum site temperature (R = 0.70, P = 0.003 for legume proportion; R = 0.64, P = 0.010 for N_gainmix/N_tot in mixture). Nevertheless, the relative N gain in mixture was not correlated to site productivity (P = 0.500), suggesting that, within climatic restrictions, balanced grass–legume mixtures can benefit from comparable relative gains in N yield across largely differing productivity levels. We conclude that the use of grass–legume mixtures can substantially contribute to resource‐efficient agricultural grassland systems over a wide range of productivity levels, implying important savings in N fertilizers and thus greenhouse gas emissions and a considerable potential for climate change mitigation.     

旅游生态系统能值研究进展

能值分析是以能值为基准,通过能值转换率,有效测度与评价生态系统及经济系统中不同类型的物质流、能量流、货币流及其相互关系的方法。旅游生态系统是特殊类型的人地关系地域系统,是以旅游活动为中心的"自然、经济、社会、旅游"复合系统,利用能值方法进行旅游能值研究可以为旅游可持续发展提供科学建议。通过对国内外相关研究重要文献的梳理,从旅游能值研究尺度与类型角度,分析了国内外相关研究进展,并通过与农业、工业系统的能值研究对比分析,目前研究在理论推进、要素选择、指标构建、方法集成等4个方面,旅游生态系统能值研究存在特殊性,并从理论、方法、内容等3个角度,提出了今后旅游能值研究的方向,以期推动旅游系统能值研究的深入。