scholarly journals Positive effects of organic farming on below-ground mutualists: large-scale comparison of mycorrhizal fungal communities in agricultural soils

2010 ◽  
Vol 186 (4) ◽  
pp. 968-979 ◽  
Author(s):  
Erik Verbruggen ◽  
Wilfred F. M. Röling ◽  
Hannes A. Gamper ◽  
George A. Kowalchuk ◽  
Herman A. Verhoef ◽  
...  
2021 ◽  
Vol 11 ◽  
Author(s):  
Francisco Massot ◽  
Panagiotis Gkorezis ◽  
Jonathan Van Hamme ◽  
Damian Marino ◽  
Bojana Spirovic Trifunovic ◽  
...  

The large-scale use of the herbicide glyphosate leads to growing ecotoxicological and human health concerns. Microbe-assisted phytoremediation arises as a good option to remove, contain, or degrade glyphosate from soils and waterbodies, and thus avoid further spreading to non-target areas. To achieve this, availability of plant-colonizing, glyphosate-tolerant and -degrading strains is required and at the same time, it must be linked to plant-microorganism interaction studies focusing on a substantive ability to colonize the roots and degrade or transform the herbicide. In this work, we isolated bacteria from a chronically glyphosate-exposed site in Argentina, evaluated their glyphosate tolerance using the minimum inhibitory concentration assay, their in vitro degradation potential, their plant growth-promotion traits, and performed whole genome sequencing to gain insight into the application of a phytoremediation strategy to remediate glyphosate contaminated agronomic soils. Twenty-four soil and root-associated bacterial strains were isolated. Sixteen could grow using glyphosate as the sole source of phosphorous. As shown in MIC assay, some strains tolerated up to 10000 mg kg–1 of glyphosate. Most of them also demonstrated a diverse spectrum of in vitro plant growth-promotion traits, confirmed in their genome sequences. Two representative isolates were studied for their root colonization. An isolate of Ochrobactrum haematophilum exhibited different colonization patterns in the rhizoplane compared to an isolate of Rhizobium sp. Both strains were able to metabolize almost 50% of the original glyphosate concentration of 50 mg l–1 in 9 days. In a microcosms experiment with Lotus corniculatus L, O. haematophilum performed better than Rhizobium, with 97% of glyphosate transformed after 20 days. The results suggest that L. corniculatus in combination with to O. haematophilum can be adopted for phytoremediation of glyphosate on agricultural soils. An effective strategy is presented of linking the experimental data from the isolation of tolerant bacteria with performing plant-bacteria interaction tests to demonstrate positive effects on the removal of glyphosate from soils.


2014 ◽  
Vol 71 (7) ◽  
pp. 1717-1727 ◽  
Author(s):  
A. Jason Phillips ◽  
Lorenzo Ciannelli ◽  
Richard D. Brodeur ◽  
William G. Pearcy ◽  
John Childers

Abstract This study investigated the spatial distribution of juvenile North Pacific albacore (Thunnus alalunga) in relation to local environmental variability [i.e. sea surface temperature (SST)], and two large-scale indices of climate variability, [the Pacific Decadal Oscillation (PDO) and the Multivariate El Niño/Southern Oscillation Index (MEI)]. Changes in local and climate variables were correlated with 48 years of albacore troll catch per unit effort (CPUE) in 1° latitude/longitude cells, using threshold Generalized Additive Mixed Models (tGAMMs). Model terms were included to account for non-stationary and spatially variable effects of the intervening covariates on albacore CPUE. Results indicate that SST had a positive and spatially variable effect on albacore CPUE, with increasingly positive effects to the North, while PDO had an overall negative effect. Although albacore CPUE increased with SST both before and after a threshold year of 1986, such effect geographically shifted north after 1986. This is the first study to demonstrate the non-stationary spatial dynamics of albacore tuna, linked with a major shift of the North Pacific. Results imply that if ocean temperatures continue to increase, US west coast fisher communities reliant on commercial albacore fisheries are likely to be negatively affected in the southern areas but positively affected in the northern areas, where current albacore landings are highest.


2015 ◽  
Vol 20 (2) ◽  
pp. 128-138 ◽  
Author(s):  
Juan Carlos Pérez Mesa ◽  
Emilio Galdeano-Gómez

Purpose – This purpose of this study is to provide empirical evidence of how cooperation is related to suppliers’ performance, a relationship that is thought to be affected by the type of customer and the extent to which the market is diversified. It analyzes horticultural exporting firms in southeastern Spain, which are the main suppliers of European markets. Together with their primary customers (large-scale retail companies such as Carrefour, Tesco and Aldi), these firms constitute a complex supply network composed of a variety of agents and sales channels. This network will be studied from the perspective of the supplier–supplier relationship that is critical to their survival. Design/methodology/approach – Starting with a detailed description of Europe’s vegetable supply chain, a hierarchical regression is used with an index of cooperation intensity, moderated by retail sales and market concentration. The authors test the hypotheses using panel data on a set of 118 horticultural marketing firms in southeast Spain for the period 2009-2011. Findings – Cooperation strategies are shown to have positive effects on performance (market creation, promotion, quality, training, joint supply purchases and research ventures). Moreover, the retail channel and market diversification are observed to have a positive effect on the relationship between cooperation and the supplier’s performance. They demonstrate that active cooperation strategies have a greater bearing on performance in those firms whose primary customers are retailers. This circumstance provides evidence of the synergies and benefits that may arise when the supplier integrates the retailer in the supply chain, but which do not arise with other types of customers. Research limitations/implications – Although this study refers to a specific sector (fruits and vegetables) and the statistical results are limited, they provide insights that may assist in understanding how other perishable produce-related industries work: such industries share many common features. Practical implications – A more stable relationship between suppliers and retailers in the perishable produce market will render the supply firm more cooperative, competitive and profitable. Increased performance does not arise from the better conditions and improved sales power offered by the customer but instead from the adaptability of the supplier. Likewise, market diversification drives the supply firm toward a cooperative strategy, making it more profitable and competitive. As a practical norm, market diversification alone will not have positive results on performance unless the firm proves capable of enhancing its capacity for cooperation. Social implications – Proper management of the agricultural produce supply chain has repercussions on all of the members of that chain, although special emphasis should be placed on producers and consumers. The availability of food, its quality and its safety depend on management during the production phase. Along these lines, and more specifically for the consumer, this work is relevant because the sector analyzed accounts for 40 per cent of the vegetables consumed in Europe. Originality/value – This article defends the supplier–supplier relationship as the starting point for the analysis of a supply network. In certain sectors, the suppliers’ ability both to solve their clients’ problems and to be profitable is conditioned on maintaining the network and, therefore, the basic focus must center on analyzing their relationships, always including the customer, who has a direct or indirect influence on those relationships. Previous research has not comprehensively addressed this issue, let alone that of a sector with agile and perishable products in which, due to its nature, decision-making about market destinations and sales channels is the order of the day.


2016 ◽  
Vol 20 (12) ◽  
pp. 4747-4756 ◽  
Author(s):  
Wenfei Liu ◽  
Xiaohua Wei ◽  
Qiang Li ◽  
Houbao Fan ◽  
Honglang Duan ◽  
...  

Abstract. Understanding hydrological responses to reforestation is an important subject in watershed management, particularly in large forested watersheds ( >  1000 km2). In this study, we selected two large forested watersheds (Pingjiang and Xiangshui) located in the upper reach of the Poyang Lake watershed, southeastern China (with an area of 3261.4 and 1458 km2, respectively), along with long-term data on climate and hydrology (1954–2006) to assess the effects of large-scale reforestation on streamflow. Both watersheds have similar climate and experienced comparable and dramatic forest changes during the past decades, but with different watershed properties (e.g., the topography is much steeper in Xiangshui than in Pingjiang), which provides us with a unique opportunity to compare the differences in hydrological recovery in two contrasted watersheds. Streamflow at different percentiles (e.g., 5, 10, 50 and 95 %) were compared using a combination of statistical analysis with a year-wise method for each watershed. The results showed that forest recovery had no significant effects on median flows (Q50%) in both watersheds. However, reforestation significantly reduced high flows in Pingjiang, but had limited influence in Xiangshui. Similarly, reforestation had significant and positive effects on low flows (Q95%) in Pingjiang, while it did not significantly change low flows in Xiangshui. Thus, hydrological recovery is limited and slower in the steeper Xiangshui watershed, highlighting that watershed properties are also important for determining hydrological responses to reforestation. This finding has important implications for designing reforestation and watershed management strategies in the context of hydrological recovery.


2018 ◽  
Vol 10 (11) ◽  
pp. 4162 ◽  
Author(s):  
Shengqin Zheng ◽  
Ke Xu ◽  
Qing He ◽  
Shaoze Fang ◽  
Lin Zhang

In China, the demand for public infrastructure projects is high due to the acceleration of urbanization and the rapid growth of the economy in recent years. Infrastructures are mainly large scale, so local governments have difficulty in independently completing financing work. In this context, public sectors often seek cooperation from private sectors, in which public–private partnership (PPP) is increasingly common. Although numerous studies have concentrated on sustainable development, the unsustainability performances of infrastructures are often reported on various media. Furthermore, studies on the sustainability performances of PPP-type infrastructure (PTI) projects are few from the perspective of private sectors’ behaviors. In this study, we adopted the modified theory of planned behavior and the structure equation model and conducted a questionnaire survey with 258 respondents for analyzing the sustainable behaviors of private sectors. Results indicated that behavioral attitude, perceived behavioral control, and subjective norm interact significantly. They have direct positive effects on behavioral intention and then indirectly influence actual behavior through this intention. Actual sustainable behaviors of private sectors have significantly positive effects on the sustainable development of cities. We offer theoretical and managerial implications for public and private sectors on the basis of the findings to ensure and promote the sustainability performances of PTI projects.


2018 ◽  
Vol 18 (4) ◽  
Author(s):  
Hiroyuki Yamada ◽  
Tien Manh Vu

Abstract In literature, there is limited direct evidence regarding the effect of health insurance coverage on firm performance and worker productivity. We study the impacts of health insurance on medium- and large-scale domestic private firms’ performance and productivity in Vietnam, using a large firm level census dataset. We find statistically, but suggestive, positive health insurance effects on both aggregate profit and profit per worker for both complying and non-complying firms when using the full sample. We further restrict the sample to specific industries. The positive health insurance effects could exist for both complying and non-complying firms in the heavy manufacturing and construction sector, while such positive effects could be only significant for complying firms in the wholesale/retail sectors. We could not find any evidence of positive health insurance effects in the light manufacturing sector. These results imply that the impacts of health insurance could be industry specific.


2021 ◽  
Author(s):  
Carl-Fredrik Johannesson ◽  
Klaus Steenberg Larsen ◽  
Brunon Malicki ◽  
Jenni Nordén

<p>Boreal forests are among the most carbon (C) rich forest types in the world and store up to 80% of its total C in the soil. Forest soil C development under climate change has received increased scientific attention yet large uncertainties remain, not least in terms of magnitude and direction of soil C responses. As with climate change, large uncertainties remain in terms of the effects of forest management on soil C sequestration and storage. Nonetheless, it is clear that forest management measures can have far reaching effects on ecosystem functioning and soil conditions. For example, clear cutting is a widely undertaken felling method in Scandinavia which profoundly affects the forest ecosystem and its functioning, including the soil. Nitrogen (N) fertilization is another common practice in Scandinavia which, despite uncertainties regarding effects on soil C dynamics, is being promoted as a climate change mitigation tool. A more novel practice of biochar addition to soils has been shown to have positive effects on soil conditions, including soil C storage, but studies on biochar in the context of forests are few.</p><p>In the face of climate change, the ForBioFunCtioN project is dedicated to investigating the response of boreal forest soil CO<sub>2</sub> and CH<sub>4</sub> fluxes to experimentally increased temperatures and increased precipitation – climatic changes in line with projections over Norway – within a forest management context. The experiment is set in a Norwegian spruce-dominated bilberry chronosequence, including a clear-cut site, a middle-aged thinned stand, a mature stand and an old unmanaged stand. Warming, simulated increased precipitation, N fertilizer and biochar additions will be applied on experimental plots in an additive manner that allows for disentangling the effects of individual parameters from interaction effects. Flux measurements will be undertaken at high temporal resolution using the state-of-the-art LI-7810 Trace Gas Analyzer (©LI-COR Biosciences). The presentation will show the experimental setup and first measurements from the large-scale experiment.</p>


2021 ◽  
pp. 089976402110573
Author(s):  
Zhiming Liu ◽  
Haiwei Jia

In this article, we extend Wilson and Musick’s concept of cultural capital, which was defined as the culture of benevolence, to a multilevel concept and build a multilevel cultural capital theory about individual (nonmandatory) volunteering based on religious beliefs, political values, belief in social justice, and belief in social trust in the context of volunteering in China. Data from the 2012 Chinese General Social Survey, China’s national and comprehensive large-scale social survey project, are used to empirically investigate the influences of individual-level cultural capital (values of benevolence) and contextual-level cultural capital (cultural climate of benevolence) on individual volunteering. In terms of individual-level cultural capital, membership in the Chinese Communist Party (China’s ruling party), belief in social justice, and belief in social trust have significant positive relationships with individual volunteering. In terms of contextual-level cultural capital, the religious climate and justice climate in a province have significant positive effects on individual volunteering.


Sign in / Sign up

Export Citation Format

Share Document