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Carbon storage in hedge biomass—A case study of actively managed hedges in England
Get PDFFarmland hedges could be managed for carbon sequestration, but empirical data on their carbon (C) stock in the UK is lacking. Lowland hedges managed by hedge laying and triennial trimming using a mechanical flail formed a dense woody structure (mean 81,368 stems ha−1). Hedges untrimmed for 3 years (mean height 3.5 m, widths 2.6–4.2 m), contained an above ground biomass (AGB) C stock of 42.0 ± 3.78 t C ha−1 (14.0 ± 1.94 t C km−1); when trimmed to 2.7 m high, and subsequently 1.9 m high, AGB C stocks were reduced to 40.6 ± 4.47 t C ha−1 (11.4 t C km−1) and 32.2 ± 2.76 t C ha−1 (9.9 t C km−1), respectively. A 4.2 m wide hedge contained 9.7 t C km−1 more AGB C stock than a 2.6 m wide hedge (mean height 3.5 m). Below ground biomass (BGB) was 38.2 ± 3.66 t C ha−1 (11.5 t C km−1). Near horizontal stems, arranged by hedge laying, 12–18 years prior to sampling, accounted for 5.2 t C ha−1 (1.6 t C km−1) of AGB C. The empirical data demonstrated how changing management practices to wider/taller hedges sequestered C in AGB. These estimates of hedgerow C stocks fill a knowledge gap on C storage and identified the need for a more comprehensive biomass inventory of hedgerows to strengthen the national carbon accounting of agro-ecosystems in the UK
Reconstructing Prehistoric African Population Structure
No full textWe assembled genome-wide data from 16 prehis- toric Africans. We show that the anciently divergent lineage that comprises the primary ancestry of the southern African San had a wider distribution in the past, contributing approximately two-thirds of the ancestry of Malawi hunter-gatherers 2,500 years ago and approximately one-third of the ancestry of Tanzanian hunter-gatherers 1,400 years ago. We document how the spread of farmers from western Africa involved complete replacement of local hunter-gatherers in some regions, and we track the spread of herders by showing that the population of a 3,100-year-old pastoralist from Tanzania contributed ancestry to people from north- eastern to southern Africa, including a 1,200-year- old southern African pastoralist. The deepest diversi- fications of African lineages were complex, involving either repeated gene flow among geographically disparate groups or a lineage more deeply diverging than that of the San contributing more to some west- ern African populations than to others. We finally leverage ancient genomes to document episodes of natural selection in southern African populations
Developing a 3-Choice Serial Reaction Time Task for Examining Neural and Cognitive Function in an Equine Model
Get PDFBackground: Large animal models of human neurological disorders are advantageous compared to rodent models due to their neuroanatomical complexity, longevity and their ability to be maintained in naturalised environments. Some large animal models spontaneously develop behaviours that closely resemble the symptoms of neural and psychiatric disorders. The horse is an example of this; the domestic form of this species consistently develops spontaneous stereotypic behaviours akin to the compulsive and impulsive behaviours observed in human neurological disorders such as Tourette’s syndrome. The ability to non-invasively probe normal and abnormal equine brain function through cognitive testing may provide an extremely useful methodological tool to assess brain changes associated with certain human neurological and psychiatric conditions. New Method: An automated operant system with the ability to present visual and auditory stimuli as well as dispense salient food reward was developed. To validate the system, ten horses were trained and tested using a standard cognitive task.
Results: All animals achieved total learning criterion and performed six probe sessions. Learning criterion was met within 16.30±0.79 sessions over a three day period. During six probe sessions, level of performance was maintained at
80.67±0.57% (mean±SEM) accuracy.
Comparison with existing method(s): This is the first mobile fully automated system developed to examine cognitive function in the horse.
Conclusions: A fully-automated operant system for mobile cognitive function of a large animal model has been designed and validated. Horses pose an interesting complementary model to rodents for the examination of human neurological
dysfunction
Development of a Multiple Protein Extract Microarray for Profiling Allergen-Specific Immunoglobulin E in Horses with Severe Asthma
No full textPersistence of Dichelobacter nodosus, the causal agent of ovine footrot
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Ovine footrot is the main cause of lameness in sheep in the UK. Information on sites where the causative
agent of footrot Dichelobacter nodosus persists may lead to changes in sheep management and disease control.
Introduction Ovine footrot (FR) is an economically important disease that causes lameness and affects sheep flocks
worldwide. It is characterized by interdigital skin inflammation (interdigital dermatitis [ID]) with, or without, separation of
the hoof horn from the underlying tissue (severe footrot [SFR]). The primary causative agent is the gram-negative
anaerobic bacterium Dichelobacter nodosus, which is thought to exclusively colonize the hoof and is transmitted indirectly via contaminated surfaces. Periods of apparent zero prevalence of FR in a flock are followed by disease occurrence when climatic conditions become favourable for pathogen transmission. This suggests that there are sites were D.nodosus persists. These sites might include the feet, gingival cavity and faeces of sheep and the environment. The aim of this study was to investigate persistence of D. nodosus, by investigating possible sites of survival, using a longitudinal study design.
Materials and methods
Study 1: From a flock of approximately 150 animals, 5 North Country Mules and 5 lambs (Northcountry mule x Texel) were selected for the study. All animals and their pasture were examined and sampled (including
swabs from feet and the gingival cavity, as well as soil, grass and faecal samples) fortnightly from June to August for a period of 8 weeks. Study 2: A flock of 120 Suffolk x Wiltshire-horn ewe lambs was screened for FR and 40 animals
without FR lesions were selected randomly and moved to a study pasture that had been unoccupied for 10 days. The study group and pasture were examined and sampled weekly for five months from January to May. For both studies, sheep were turned and scored for ID and SFR lesions using a 4-point scale (Moore, et al., 2005). Swabs were taken from the
interdigital skin of the foot (study 1: n=40, study 2: n=160) and from the gingival cavity (study 1: n=10, study 2: n=40) at every visit. Faecal samples (n=10) were collected from the pasture (study 1 only). For study 2 faecal samples (n=40) were taken directly from the animal. Soil samples (n=22) were collected weekly and grass samples were taken when present at these sites (n=6). Local climate data (ambient temperature [°C] and rainfall [mm]) was collected. All samples from study 1 were analysed resulting in a total of 342 samples. For study 2, DNA was extracted from 7 sheep (5 sheep with footrot lesions and 2 control sheep with no disease), and all samples collected from the pasture; a total of 898 samples. Real-time PCR used to detect and quantify D.nodosus. Chi square tests using R software were used for the preliminary statistical
analysis.
Results
Flock disease prevalence was higher in study 1 than in study 2. The climate during study 1 was warm and initially
wet, but became progressively drier and the climate during study 2 was cold and dry. D. nodosus was detected in all
sample types in both studies but not on all occasions (Table 1). Detection levels differed significantly between the two
studies in feet, gingival cavity, soil, and grass samples (P<0.01). The proportion of positive foot swabs was greater than
expected by chance (P<0.01) in both studies. The proportion of positive faecal samples (study 1) and grass samples (study
2) was lower than expected by chance (P<0.05).
Conclusions
For the first time we show that D. nodosus can be shed in ovine faeces. The differences in detection between
studies are likely to be attributable to differences in disease status of the study groups and climatic conditions. D. nodosus was detected in all sample types in both studies but was less prevalent in non-foot sites, especially when the weather was dry, suggesting that feet are the more likely place of persistence. A binomial mixed regression model will be used to further
elucidate variables temporally associated with the presence of D. nodosus in feet, in the gingival cavity and on the pasture
Fiat Lux: Functional Analysis of Three Saxo-Norman Pottery Lamps from Berkeley, Gloucestershire
No full textTHIS PAPER COMPRISES analysis of three Saxo-Norman pottery lamps recovered during archaeological excavations in 2012 in the Edward Jenner Museum garden, Berkeley, Gloucestershire. While such vessels have been known to archaeologists since the earliest days of Saxon and medieval pottery studies, their specific function, other than general �lighting�, has never been considered. Similarly, the composition of the fuel in such lamps has not been scientifically verified. In the following paper, both of these areas are addressed through experimental archaeology and organic residue analysis. The conclusion reached is that the lamps were chosen for use in a late-Saxon industrial workshop as they were ideal for the setting, providing a consistent, stable and bright light source in comparison with other available lighting methods of the period
Using scenario-based influence mapping to examine farmers’ biosecurity behaviour
Get PDFUnderstanding of farmers’ influences relating to biosecurity is surprisingly weak, beyond general remarks that farmers tend to trust their private vet. Previous studies have explored influences in relation to single issue events. There is a need for better methodologies to fully appreciate how farmers’ biosecurity practices are shaped. Using bovine Tuberculosis as a case study, this paper uses stakeholder mapping methods applied across different scenarios. The aim is to identify how farmers’ responses to animal disease policy are shaped by their relationships with different actors. Interviews were conducted with 50 farmers in three areas in England. Farmers were presented with four scenarios to control bovine TB: 1) a badger cull, 2) an oral badger vaccine, 3) a cattle vaccine and 4) a range of control measures. The results show that as things get more uncertain, government institutions become more influential. Government institutions and government vets are also important in situations where farmers do not consider themselves ‘experts’ i.e. vaccination as opposed to culling. The influence of other farmers was not universal; it differed between scenarios. These data show the value of scenario-based stakeholder mapping as a methodology that can enable biosecurity researchers to: more accurately and systematically determine stakeholder influence and understand how these influences change and evolve; understand the role of farmer biosecurity practices, the self-concept and ‘good farming’; and identify broader logics of biosecurity that influence and potentially frustrate animal disease policy goals
