Soil and Leaf Sampling in Apple Orchards

In an investigation to determine the best ways in which to take soil and leaf samples characteristic of an orchard, 40 commercial orchards of Cox’s Orange Pippin, selected at random from the major fruit growing areas of England, were examined over a period of three years. It was found that:

1. 24 cores should be taken at random throughout an orchard in such a way that rows and alleyways contribute equally. The cores should be bulked, thoroughly mixed, and a single sub-sample taken for analysis. In any given season 80 per cent, confidence limits on the resulting determinations will be ±0.24 pH units, ±4·7 p.p.m. of P, ±24·1 p.p.m. of K, and ±13·3 p.p.m. of Mg.

2. For leaves taken from the middle third of current year’s extension growths in late August, a total of 100 leaves should be picked from at least five randomly selected trees. The leaves should be dried, ground, thoroughly mixed, and a single sub-sample taken for analysis. In any given season the 80% confidence limits on the resulting determinations will be ±0·22% N, ±0–01% P, ±0·17% K, ±0·18% Ca, and ±0.03% Mg, all in terms of dry matter.

It was noted that according to soil and leaf analyses the nutrient levels in the majority of the orchards were at least adequate for fruit growing. There was no relationship between any single nutrient concentration in soil or leaf and tree performance.     

The Interpretation of Leaf Analyses

The problem of interpreting the effects of cultural treatments on the chemical composition of leaves is studied by successively applying a number of alternative methods to the same example involving repeated sampling over a number of years. These methods are the analysis of variance applied to each element separately, the use of ratios of pairs of elements, the use of a system of trilinear co-ordinates to express the N-P-K balance and the K-Ca-Mg balance, and the simultaneous study of all elements by means of Principal Component Analysis. The relative merits of the different methods are assessed by their ability to produce consistent results from year to year. As the number of elements to be examined simultaneously is increased, so there appears a progressive increase in consistency until the method of interpretation is one involving all elements. It is concluded that a reasoned application of the Principal Component Analysis approach, which places no restriction on the number of elements that can be examined, can lead to a greater understanding of the effects of treatments on leaf composition as a whole than any examination of individual elements or simple ratios.     

Habitat connectivity for pollinator beetles using surface metrics

Measuring habitat connectivity in complex landscapes is a major focus of landscape ecology and conservation research. Most studies use a binary landscape or patch mosaic model for describing spatial heterogeneity and understanding pattern-process relationships. While the value of landscape gradient approaches proposed by McGarigal and Cushman are recognized, applications of these newly proposed three dimensional surface metrics remain under-used. We created a gradient map of habitat quality from several GIS layers and applied three dimensional surface metrics to measure connectivity between 67 locations in Indiana, USA surveyed for one group of ecosystem service providers, flower longicorn beetles (Cerambycidae: Lepturinae). The three dimensional surface metrics applied to the landscape gradient model showed great potential to explain the differences of lepturine assemblages among the 2,211 studied landscapes (between site pairs). Surface kurtosis and its interaction with geographic distance were among the most important metrics. This approach provided unique information about the landscape through four configuration metrics. There were some uniform trends of the responses of many species to some of surface metrics, however some species responded differently to other metrics. We suggest that three dimensional surface metrics applied to a habitat surface map created with insight into species requirements is a valuable approach to understanding the spatial dynamics of species, guilds, and ecosystem services.     

Conservation priorities for freshwater biodiversity: The Key Biodiversity Area approach refined and tested for continental Africa

Freshwater ecosystems represent one of the most threatened broad habitat types globally. Despite containing around a third of all vertebrates, area-based approaches to conservation planning rarely include freshwater species as an explicit target for conservation. Here we describe and apply a globally applicable methodology comparable to those for other groups (i.e. Important Bird Areas) to identify river and lake catchments that represent, or contain, freshwater Key Biodiversity Areas. We discuss the rationale behind the methodology and propose appropriate definitions and quantitative threshold values for the selection criteria. Thresholds are developed through spatial analysis of species information for four comprehensively assessed freshwater taxonomic groups in continental Africa, comprising 4203 species, as recently assessed for the IUCN Red List of Threatened Species?. To illustrate application of the methodology freshwater Key Biodiversity Areas are identified across continental Africa, and conservation planning software used to prioritise a network of catchments that captures 99% of the total species complement within catchments covering ca. 20% of the total land area. Within these prioritised catchments only 19% of river length falls within existing Protected Areas suggesting that, given the high connectivity within freshwater ecosystems and their dependence upon catchment management for effective conservation, modification or expansion of the protected area network is required to increase effective conservation of freshwater species. By applying this methodology, gaps in the coverage of freshwater species by existing Protected Areas can be identified and used to inform conservation policy and investment to ensure it is inclusive of, and effective for, freshwater biodiversity.     

Is it good or bad to fish with FADs? What are the real impacts of the use of drifting FADs on pelagic marine ecosystems?

The use of fish aggregating devices (FADs) by purse seine fisheries has come under increasing criticism for its potential deleterious impacts on tuna stocks, for high levels of by‐catch and threats to the biodiversity of tropical pelagic ecosystems. Here, we review the current state of scientific knowledge of this fishing technique and current management strategies. Our intent is to encourage objective discussion of the topic and highlight areas worthy of future research. We show that catching juvenile tuna around FADs does not necessarily result in overfishing of stocks, although more selective fishing techniques would likely help obtain higher yield. Levels of non‐tuna by‐catch are comparable to or less than in other commercial tuna fisheries and are primarily comprised of species that are not considered threatened. Accordingly, to minimize impacts on ecosystem balance, there is merit in considering that all species captured in purse seine fisheries (excluding vulnerable species such as turtles and sharks) should be retained, but the consequences of such a measure should be carefully examined before implementation. The take of vulnerable species could be further reduced by introduction of additional mitigation measures, but their potential benefits would be limited without parallel efforts with other gears. Finally, there is no unequivocal empirical evidence that FADs represent an ‘ecological trap’ that inherently disrupts tuna biology although further research should focus on this issue. We encourage RFMOs to expand and improve their FAD management plans. Under appropriate management regimes, FAD fishing could be an ecologically and economically sensible fishing method.     

Detection of feline herpesvirus 1 DNA in skin biopsy specimens from cats with or without dermatitis

OBJECTIVE: To compare detection rates of feline herpesvirus 1 (FHV-1) DNA in skin biopsy specimens from cats with herpetic dermatitis, cats with nonherpetic dermatitis, and cats without dermatitis. DESIGN: Prevalence survey. Animals-5 cats (9 biopsy specimens) with herpetic ulcerative dermatitis, 14 cats (17 biopsy specimens) with nonherpetic ulcerative dermatitis, and 8 cats (21 biopsy specimens) without clinically apparent skin lesions. PROCEDURES: A single-phase PCR assay was used to detect FHV-1 DNA in biopsy specimens. Assay results were compared with results of histologic examination. RESULTS: FHV-1 DNA was detected in all 9 biopsy specimens from the 5 cats with herpetic dermatitis and in 1 of 17 biopsy specimens from the 14 cats with nonherpetic dermatitis, but was not detected in any of the 21 biopsy specimens from the 8 cats without dermatitis. When results of histologic examination were used as the gold standard, sensitivity and specificity of the PCR assay were 100% and 95%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results confirmed that FHV-1 DNA can be detected in the skin of cats with herpetic dermatitis and suggest that the virus may play a causative role in the disease. In addition, the PCR assay may be useful in confirming a diagnosis of herpetic dermatitis.     

An automated sensor-based method of simple behavioural classification of sheep in extensive systems

Automated sensor-based behaviour classification systems are already developed and used for cattle in an agricultural context.To develop a similar tool for sheep we investigated the use of pitch and roll tilt sensors to provide information about sheep behaviour. The aim was to determine if different behaviour types associated with grazing can be accurately identified using tilt sensor data. We collected data from two adjacent enclosures at two contrasting sites, one in the Southern Uplands grazed by Cheviot ewes and one in the Western Highlands of Scotland grazed by Scottish Blackface ewes. In addition to our observations of ewes on hill pasture we also observed collared ewes in flat and gently sloped fields and in a shed to evaluate the tilt data. The data was analysed using three classification methods, a linear discriminant analysis, a classification tree method, and a manually developed decision tree consisting of four “if then” loops.We found that we can distinguish between the two behaviour categories “active” and “inactive”, even if only pitch tilt data is used. All three methods provide very good classification predictions with more than 90% correct results. However, the classification tree method was less robust than the other methods. Using the manually developed decision tree, we produced results of activity that were robust and credible.By using the behaviour classification we are able to collect data on different genotypes, systems or management options in sheep farming, and in combination with GPS we will be able to improve management strategies and gain information about grazing ecology. It can also be seen as a first step to support farmers with a viable system to comply with welfare regulations in the light of European Union Common Agricultural Policy and as an integral part for future developments regarding virtual fencing technology for sheep.     

Proximal fluorescence sensing of potassium responsive crops to develop improved predictions of biomass,yield and grain quality of wheat and barley

Precision Agriculture - Precision nutrient management requires accurate assessment of crop nutrient status. This is common for assessing N status, but much less so for other nutrients. Because...     

Ultrasonographic appearance and abdominal haemorrhage associated with a juvenile granulosa cell tumour in a foal

Granulosa cell tumours are commonly identified in mares, but have rarely been identified in equine neonates. This report describes a septic neonatal foal that presented with haemoabdomen secondary to a ruptured ovarian granulosa cell tumour. The ultrasonographic appearance, successful surgical removal and histopathological appearance of the tumour is described. Juvenile ovarian granulosa cell tumours differ histologically from adult granulosa cell tumours. Ultrasound is a useful way to identify haemoabdomen and abdominal masses in foals. Juvenile granulosa cell tumour should be considered as a differential for this combination in neonatal foals.