There is growing evidence of the importance of extramatrical mycelium (EMM) of mycorrhizal fungi in carbon (C) cycling in ecosystems. However, our understanding has until recently been mainly based ...on laboratory experiments, and knowledge of such basic parameters as variations in mycelial production, standing biomass and turnover as well as the regulatory mechanisms behind such variations in forest soils is limited. Presently, the production of EMM by ectomycorrhizal (EM) fungi has been estimated at ~140 different forest sites to be up to several hundreds of kg per ha per year, but the published data are biased towards Picea abies in Scandinavia. Little is known about the standing biomass and turnover of EMM in other systems, and its influence on the C stored or lost from soils. Here, focussing on ectomycorrhizas, we discuss the factors that regulate the production and turnover of EMM and its role in soil C dynamics, identifying important gaps in this knowledge. C availability seems to be the key factor determining EMM production and possibly its standing biomass in forests but direct effects of mineral nutrient availability on the EMM can be important. There is great uncertainty about the rate of turnover of EMM. There is increasing evidence that residues of EM fungi play a major role in the formation of stable N and C in SOM, which highlights the need to include mycorrhizal effects in models of global soil C stores.
Global increases in sea temperatures and atmospheric concentrations of CO₂ may affect the health of calcifying shellfish. Little is known, however, about how competitive inter actions within and ...between species may influence how species respond to multiple stressors. We experimentally assessed separate and combined effects of temperature (12 or 16°C) and atmospheric CO₂ concentrations (400 and 1000 ppm) on the health and biological functioning of native (Ostrea edulis) and invasive (Crassostrea gigas) oysters held alone and in intraspecific or interspecific mixtures. We found evidence of reduced phagocytosis under elevated CO₂ and, when combined with increased temperature, a reduction in the number of circulating haemocytes. Generally, C. gigas showed lower respiration rates relative to O. edulis when the species were in intraspecific or interspecific mixtures. In contrast, O. edulis showed a higher respiration rate relative to C. gigas when held in an interspecific mixture and exhibited lower clearance rates when held in intraspecific or interspecific mixtures. Overall, clearance rates of C. gigas were consistently greater than those of O. edulis. Collectively, our findings indicate that a species’ ability to adapt metabolic processes to environmental conditions can be modified by biotic context and may make some species (here, C. gigas) competitively superior and less vulnerable to future climatic scenarios at local scales. If these conclusions are generic, the relative role of species interactions, and other biotic parameters, in altering the outcomes of climate change will require much greater research emphasis.
Translocation is shown of phosphorus, nitrogen, potassium and magnesium to a P-deficient host from ectomycorrhizal fungal hyphae. Mycorrhizal (with Paxillus involutus) and nonmycorrhizal P-deficient ...spruce (P. abies) seedlings were grown in a two-compartment sand-culture system. Hyphal translocation of nutrients from the inner compartment (penetrated only by hyphae) to the host was measured using mass balance (for N, P and K) or stable isotope (15N and25Mg) methods. Addition of P to the hyphal compartment strongly stimulated hyphal growth, and this also increased both seedling P status and growth. Hyphae translocated nonlimiting elements in addition to P, contributing 52, 17, 5 and 3-4%, respectively, to total P, N, K or Mg plant uptake. The potential role of the ectomycorrhizal mycelium in K acquisition was demonstrated. Translocation to mycorrhizal seedings of N, K and Mg was strongly reduced when hyphal P-fluxes ceased; this translocation of nonlimiting nutrients depended on simultaneous translocation of P. The ectomycorrhizal mycelium has an active role in P acquisition from sources not available to roots. Nutrient fluxes within fungal hyphae are interdependent and strong coupling of N, K and Mg fluxes with long-distance P translocation in the mycorrhizal mycelium occurs.
The goal of this study was to assess the relationship between hospitalization rates and asthma prevalence in New York City children and investigate the role that sociodemographic factors play in ...asthma.
A parent-report questionnaire was distributed in 26 randomly selected New York City public elementary schools, stratified according to neighborhood hospitalization rates.
The overall student response rate was 76.9% (5250 students). Prevalence of current asthma was 17.9%, 9.59%, 6.39% (
p < .001) in areas of high, median, and low asthma hospitalization rates, respectively. The overall prevalence of current asthma was 13.0%. Children living in predominantly low socioeconomic status (SES) communities had a 70% greater risk of current asthma, independent of their own ethnicity and income level. Asthma prevalence within different ethnic and income groups was consistently lower in neighborhoods of greater socioeconomic status, except among Puerto Rican children, who had high asthma prevalence, regardless of school attended or income.
Prevalence of current asthma is strongly associated with attending a school in a low-income neighborhood. Although hospitalization rates have been used as an indicator of the burden of asthma in a neighborhood, it alone does not reflect the level of disparities that exist among communities with different socioeconomic backgrounds.
Abstract Climate change is known to affect the distribution and composition of species, but concomitant alterations to functionally important aspects of behaviour and species-environment relations ...are poorly constrained. Here, we examine the ecosystem ramifications of changes in sediment-dwelling invertebrate bioturbation behaviour—a key process mediating nutrient cycling—associated with near-future environmental conditions (+ 1.5 °C, 550 ppm pCO 2 ) for species from polar regions experiencing rapid rates of climate change. We find that responses to warming and acidification vary between species and lead to a reduction in intra-specific variability in behavioural trait expression that adjusts the magnitude and direction of nutrient concentrations. Our analyses also indicate that species behaviour is not predetermined, but can be dependent on local variations in environmental history that set population capacities for phenotypic plasticity. We provide evidence that certain, but subtle, aspects of inter- and intra-specific variation in behavioural trait expression, rather than the presence or proportional representation of species per se, is an important and under-appreciated determinant of benthic biogeochemical responses to climate change. Such changes in species behaviour may act as an early warning for impending ecological transitions associated with progressive climate forcing.
The Ecosystem Approach is increasingly being adopted as a framework for developing environmental policy because it forms a strategy for the management and sustainable use of land, water and living ...resources. Yet it is not clear how this approach translates into policies that will create the integrated management necessary to protect the environment and supply the benefits which society values. Here we explore the disconnect between current policy and legislation aiming to conserve and protect specific components of coastal wetland ecosystems, and the aspirations of the Ecosystem Approach. Using an estuarine case study, we illustrate the benefits that people value from coastal wetlands and evaluate the extent to which current institutional arrangements protect these benefits. We find that cultural services are the most valued, particularly recreational activities and the enhancement of human wellbeing through a sense of belonging. Although many laws exist that relate to different components of coastal wetland areas, a diversity of organisations are responsible for their implementation, and they do not always adequately protect the benefits most valued by people. In order to successfully move towards the implementation of an Ecosystem Approach, we argue that new institutional arrangements are required. These need to encompass formal laws that protect those ecosystem processes and functions that are necessary to support valued benefits, whilst recognising the need for bridging and coordinating networks of organisations for the integrated management of coastal wetlands.
The COVID-19 pandemic has emphasized the importance of accurate detection of known and emerging pathogens. However, robust characterization of pathogenic sequences remains an open challenge. To ...address this need we developed SeqScreen, which accurately characterizes short nucleotide sequences using taxonomic and functional labels and a customized set of curated Functions of Sequences of Concern (FunSoCs) specific to microbial pathogenesis. We show our ensemble machine learning model can label protein-coding sequences with FunSoCs with high recall and precision. SeqScreen is a step towards a novel paradigm of functionally informed synthetic DNA screening and pathogen characterization, available for download at www.gitlab.com/treangenlab/seqscreen .
Laser Therapy in Veterinary Medicine: Photobiomodulation is a complete guide to using therapeutic lasers to treat veterinary patients, focusing on practical information. - Offers a comprehensive ...resource for incorporating therapeutic lasers in veterinary practice - Focuses on practical information tailored for the veterinary clinic - Written by 37 leading experts in veterinary laser therapy - Provides a thorough foundation on this standard-of-care modality - Emphasizes clinical applications with a real-world approach
Bt technologies have played a major role in the control of bollworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), in cotton.Variation in expression levels among varieties and plant parts, along ...with selection pressure on bollworm populations, has led to the development of resistance to some Bt proteins. Trials were conducted to evaluate how cotton varieties expressing different Bt proteins affect bollworm larval behavior and their damage in flowering cotton. Differences in larval recovery were observed among cotton varieties at 3 d with 3-gene Bt cotton having the lowest recovery and non-Bt cotton having the greatest recovery. Loss of bloom tags and abscission of small bolls at the site of infestation affected bollworm larval recovery among varieties. Day after infestation was the main factor that affected bollworm movement across all varieties. Number of total damaged fruiting forms by an individual bollworm larva was different among all varieties. Overall, flower bud (square) and fruit (boll) damage by an individual larva was lower on 3-gene cotton than 2-gene cotton and non-Bt cotton. An individual larva damaged fewer squares on 2-gene cotton than non-Bt cotton, but boll damage from bollworm was similar among 2-gene cotton and non-Bt cotton. The level of square and boll damage in 2-gene cotton has increased compared to previous research further supporting the occurrence of bollworm resistance to Cry proteins. The 3-gene cotton containing the Vip3A gene experienced low levels of damage and survival. These results will be important for improving management recommendations of bollworm in Bt cotton technologies.
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