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Komathi Kolandai-Matchett Maria Armoudian Simon Thrush Jenny Hillman Luitgard Schwendenmann Julia Jakobsson Tim Haggitt Caitlin O'Hara Blain Gavin Lear 《水产资源保护:海洋与淡水生态系统》2021,31(11):3034-3055
- The ocean's remoteness, ecological complexities, lengthy ecosystem processes, and vulnerability to multiple and cumulative anthropogenic threats make marine conservation communication particularly difficult. Both scientists and journalists face unique challenges in explaining the science of these often out-of-sight ecosystems. Given the inadequacies of marine news, improvement appeared necessary. However, the experiences and views of journalists and scientists have hardly been examined within marine news contexts. Thus, this study sought the perspectives of these two professional groups to provide a discussion on ways to improve news coverage of complex ocean issues through enhanced journalist–scientist working relations.
- Both journalists and scientists rated the quantity, breadth and quality of marine news as average and were receptive to alternative ways for reporting ecosystem complexities. Although some frustrations remain, both valued impactful news stories resulting from their working relations and preferred direct contact with each other over indirect methods such as press releases and science news platforms. Both groups generally agreed on what to include in marine news, but scientists favoured a collaborative approach to news content decision-making more strongly than journalists.
- Journalists' and scientists' commonly shared views and goals concerning marine news identified in this study could serve as a common ground for uniting the two professions. Institutional policies that permit one-on-one journalist–scientist interactions could lead to mutual understandings about the contexts of their relationship challenges. More trustful and mutually beneficial relationships, in turn, could be a basis for a more collaborative news generation process. Compiling and making marine visuals readily accessible to journalists; training programmes that enhance journalists' and scientists' understanding of the influence of media message framing on conservation actions; media appreciation of marine ecosystem complexities' newsworthiness; and the notion of media's social responsibility in reporting marine conservation issues could contribute to more impactful coverage.
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Competition for nutrients between plants and microbes is an important determinant for plant growth, biodiversity and carbon cycling. Perturbations such as drought affect the availability of nitrogen (N) and phosphorus (P), and may cause shifts in uptake of N and P between plants and microbes. Competitiveness for these nutrients may depend on how flexible plants and microbes are in taking up N and P. We used a novel dual isotope labelling technique (15N and 32P) to assess short-term uptake of N and P by plants and microbes affected by drought in two different plant–soil systems. Mesocosms were extracted from two grassland sites differing in soil nutrient availability and plant species. Half of the mesocosms were subjected to drought one week prior to injection of 15N (as KNO3) and 32P (as H3PO4) tracers. Uptake rates of and P in plants and microbes were estimated based on average source pool enrichment during the labelling period and on plant and microbial recovery of 15N and 32P measured after 4 days of labelling. Overall competition for N and P was reduced with drought as less and P was taken up in plants and microbes. However, plant uptake of was more sensitive to drought than microbial uptake, while microbial P uptake was more sensitive than plant P uptake. These different sensitivities to drought by plants and microbes may decouple the N and P cycle with increased drought conditions. 相似文献
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Tiago Mota Dutra Maria da Graça Batista João CA Teixeira Silvia Todorova Luísa Oliveira João Tavares Isabel Borges António Onofre Soares 《Pest management science》2023,79(10):3712-3720
BACKGROUND
Tuta absoluta (Meyrick) is a major pest of tomato produced in glasshouses and open field, causing severe damages to crops, reducing the quality of tomato fruits. The current maintenance of the pest populations below the economic threshold is not achieved by natural and classical control, thus requiring the continuous application of biological control agents (BCAs), under an augmentative or inoculative approach. The present study aims to develop an economic and financial model to evaluate the commercial viability of a continuous mass production of Macrolophus pygmaeus (Rambur), a BCA commonly used against the tomato moth, Tuta absoluta, in protected culture. The estimations for our model were based on two approaches: the farm-level impact analysis and the benefit–cost analysis.RESULTS
The results of the farm-level analysis show that the adoption of a more sustainable biological control approach is profitable for farmers and the benefit–cost analysis provides evidence that the investment on a new factory dedicated to the mass rearing of M. pygmaeus to control tomato moth populations generates a positive net present value (NPV) of 7.2 million euros, corresponding to an internal rate of return (IRR) of 28.4% per year.CONCLUSION
Our results are in line with (i) the more recent European Commission proposals for a new Regulation on sustainable use of plant protection products, which includes the reduction of 50% the use and risk of chemical pesticides by 2030 and (ii) most of the existing literature which conclude that new projects on BCA production are worth investments. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献144.
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《Pedobiologia》2014,57(4-6):197-203
Functional relationships between belowground detritivores and/or symbionts and aboveground primary producers and their herbivores are not well studied. In a factorial greenhouse experiment we studied interactions between earthworms (addition/no addition of Lumbricus terrestris; Clitellata: Lumbricidae) and arbuscular-mycorrhizal fungi (AMF; with/without inoculation of Glomus mosseae; Glomerales: Glomeraceae) on the leguminous herb Trifolium repens (Fabales: Fabaceae) and associated plant aphids (Aphis gossypii, A. craccivora; Hemiptera: Aphidoidea). In order to be able to trace organismic interactions, earthworms were dual-labelled with stable isotopes (15N-ammonium nitrate and 13C-glucose). We specifically wanted to investigate whether (i) isotopic signals can be traced from the labelled earthworms via surface castings, plant roots and leaves to plant aphids and (ii) these compartments differ in their incorporation of stable isotopes. Our results show that the tested organismic compartments differed significantly in their 15N isotope enrichments measured seven days after the introduction of earthworms. 15N isotope incorporation was highest in casts followed by earthworm tissue, roots and leaves, with lowest 15N signature in aphids. The 13C signal in roots, leaves and aphids was similar across all treatments and is for this reason not recommendable for tracing short-term interactions over multitrophic levels. AMF symbiosis affected stable isotope incorporation differently in different subsystems: the 15N isotope signature was higher below ground (in roots) but lower above ground (leaves and aphids) in AMF-inoculated mesocosms compared to AMF-free mesocosms (significant subsystem × AMF interaction). Aphid infestation was unaffected by AMF and/or earthworms. Generally, these results demonstrate that plants utilize nutrients excreted by earthworms and incorporate these nutrients into their roots, leaf tissue and phloem sap from where aphids suck. Hence, these results show that earthworms and plant aphids are functionally interlinked. Further, 15N-labelling earthworms may represent a promising tool to investigate nutrient uptake by plants and consequences for belowground-aboveground multitrophic interactions. 相似文献
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Abstract Despite being a major domain of global food supply, rice–wheat (RW) cropping system is questioned for its contribution to biomass burning in Indo-Gangetic Plains (IGP). Enhancing the yield and soil quality properties in this system is therefore necessary to reduce environmental degradation and maintain agricultural productivity. A field experiment evaluated the effects of soil management practices such as rice residue (RS) incorporation, and nitrogen (N) application on crop yield and micronutrients transformations in a RW cropping system of north-western India. The results revealed that N application (120?kg N ha?1) and RS incorporation (7.5 t ha?1) significantly increased micronutrients cations and crop yield compared with no-residue (RS0). Irrespective of N application, crop grain yield under RS incorporation (Rs7.5 t ha?1) was significantly higher than RS0 incorporation. Significant increase in all the micronutrient transformations was recorded in N120/Rs7.5 t ha?1 compared with RS0. Among different fractions, crystalline Fe bound in Zn, Mn, and Cu and amorphous Fe oxide in Fe fractions were the dominant fractions under N application (N120) and RS incorporation (RS7.5) treatment. Our study showed that application of N120 followed by RS7.5 can be more sustainable practice under RW cropping system for improvement in micronutrients availability and crop yield. This practice also provides an opportunity to incorporation of crop residues as an alternative to burning, which causes severe air pollution in the RW cropping system in the IGP. 相似文献