Technology Adoption And Pest Control Strategies Among UK Cereal Farmers: Evidence from Parametric and Nonparametric Count Data Models

This paper examines technology adoption and integrated pest management strategies employed by UK farmers, using both parametric and nonparametric methods. We employ a unique survey data set collected from UK cereal farmers to assess the determinants of technology adoption in relation to pest management. Our preferred model specification is nonparametric which makes use of the recently developed methods of Li and Racine (2007) and Racine and Li (2004). These methods allow us to combine categorical and continuous data and thereby avoid sample splitting and resulting efficiency losses. Our analysis reveals that total area farmed is positively related to the number of technologies adopted, whereas age is negatively related. We also find evidence of significant statistical differences for number of adoptions by region across the UK.technology, adoption, cereal farming, UK, nonparametric

Chitosan reduces water solubility of phosphorus in poultry litter

The addition of chemical amendments to land applied poultry litter is paramount to the maintenance of acceptable phosphorus (P) and nitrogen (N) levels in stormwater runoff from pasture. Chitin is the chief component of shrimp shells, and together with its more processed form chitosan, may show promising P, N, and metal ion chelation characteristics by virtue of its chemical structure and unique charge distribution. The objective of this study was to measure the effects of aluminum sulfate (alum, Al2(SO4)3) on aqueous solubility of P and ammonia (NH3) release against those of chitin and three varieties of chitosan in poultry litter. The experiments revealed that while chitin has little to no effect on water extractable P (WEP), all three varieties of chitosan show decreases in WEP not significantly different from those of alum. While alum significantly decreased NH3 volatilization from litter samples, neither chitin nor chitosan significantly affected released NH3

Integrated Pest Management Portfolios in UK Arable Farming: Results of a Farmer Survey

BACKGROUND. Farmers are faced with a wide range of pest management (PM) options which can be adopted in isolation or alongside complement or substitute strategies. This paper presents the results of a survey of UK cereal producers focusing on the character and diversity of PM strategies currently used by, or available to, farmers. In addition, the survey asked various questions pertaining to agricultural policy participation, attitude toward environmental issues, sources of PM advice and information and the important characteristics of PM technologies. RESULTS. The results indicate that many farmers do make use of a suite of PM techniques and that their choice of integrated PM (IPM) portfolio appears to be jointly dictated by farm characteristics and Government policy. Results also indicate that portfolio choice does affect the number of subsequent insecticide applications per crop. CONCLUSIONS. These results help to identify the type of IPM portfolios considered adoptable by farmers and highlight the importance of substitution in IPM portfolios. As such, these results will help to direct R&D effort toward the realisation of more sustainable PM approaches and aid the identification of potential portfolio adopters. These findings highlight the opportunity a revised agri-environmental policy design could generate in terms of by enhancing coherent IPM portfolio adoption.Pest management; pesticide alternatives; technology and portfolio approaches;

The Mg/Ca–temperature relationship in brachiopod shells: calibrating a potential palaeoseasonality proxy

Brachiopods are long-lived, long-ranging, extant organisms, of which some groups precipitate a relatively diagenetically stable low magnesium calcite shell. Previous work has suggested that the incorporation of Mg into brachiopod calcite may be controlled by temperature (Brand et al., 2013). Here we build upon this work by using laser ablation sampling to define the intra-shell variations in two modern brachiopod species,Terebratulina retusa (Linnaeus, 1758) and Liothyrella neozelanica (Thomson, 1918). We studied three T. retusa shells collected live from the Firth of Lorne, Scotland, which witnessed annual temperature variations on the order of 7 °C, in addition to four L. neozelanica shells, which were dredged from a water depth transect (168–1488 m) off the north coast of New Zealand. The comparison of intra-shell Mg/Ca profiles with shell δ<sup>18</sup>O confirms a temperature control on brachiopod Mg/Ca and supports the use of brachiopod Mg/Ca as a palaeoseasonality indicator. Our preliminary temperature calibrations are Mg/Ca = 1.76 ± 0.27 e<sup>(0.16 ± 0.03)T</sup>, R<sup>2</sup> = 0.75, for T. retusa and Mg/Ca = 0.49 ± 1.27 e<sup>(0.2 ± 0.11)T</sup>, R<sup>2</sup> = 0.32, for L. neozelanica (errors are 95% confidence intervals)

V s and density structure beneath the Colorado Plateau constrained by gravity anomalies and joint inversions of receiver function and phase velocity data

The Colorado Plateau is a physiographic province in the western US with an average elevation of ∼1.9 km where, in contrast to neighboring provinces, there is little evidence of large scale tectonic deformation or magmatism. Recent availability of Earthscope/USArray seismic data allow us to better examine the crust and upper mantle structure beneath the region and test proposed explanations for the plateau's uplift and relative stability. Using phase velocities for fundamental mode Rayleigh waves and P receiver functions, we perform over 800 joint inversions for 1-D shear wave velocity VS profiles sampling the plateau and surrounding regions down to 150 km depth. We image a sharp change in crustal thickness at the western edge of the Colorado Plateau with a more gradual increase eastward moving into the Rocky Mountains. A relatively thick (≳100 km) lithosphere beneath the plateau extends into the Rocky Mountains to the north. We use empirical scaling relations to estimate densities from our VS results, and predict the associated gravity anomalies, which are inconsistent with the observed distribution of the Bouguer gravity anomalies. We somewhat reconcile the prediction and observations by assuming that lateral density variations below 50 km can be ignored and the lithospheric root is therefore neutrally buoyant. While there is some evidence for small scale convection and lithospheric removal at its edges, the shape of the lithospheric mantle anomaly is consistent with a large scale uplift of the plateau by heating since removal of the Farallon slab. We conclude that the lithospheric root is key to the long term stability of the Colorado Plateau, leading to a colder, stronger crust

Co-seismic deformation of deep slabs based on summed CMT data

We assess the co-seismic deformation inferred from earthquake moment tensor solutions for subducting slabs at depths greater than 50 km globally. We rotate each moment tensor into a local slab reference frame, then sum tensors within 50 km depth bins to approximate long term deformation characteristics. This builds upon previous analyses by using the up-to-date global Centroid Moment Tensor catalog, incorporating a more complete slab geometry, and focusing on the 3-D aspects of slab deformation. Results show a general consistency with Isacks and Molnar (1969), who found that most slabs can be divided into intermediate-extensional, intermediate-extensional-deep-compressional, and intermediate to deep-compressional categories. Exceptions to these three categories can be related to slab bending in the top 100 km, plate convergence that is oblique to the trench normal direction, and regions of higher focal mechanism heterogeneity. The regions of higher focal mechanism heterogeneity appear where there are along-strike changes in slab geometry and/or evidence of double-seismic zones. We find that the sense of deformation in the intermediate strain axis direction is opposite to that of the down-dip direction, in agreement with Kuge and Kawakatsu (1993). By quantitative comparison to numerical models of global mantle flow, we show that these observations are consistent with deformation of viscous slabs responding to their own negative buoyancy and an upper to lower mantle viscosity increas

Mapping the e-Learning Assessment Domain: Concept Maps for Orientation and Navigation

Concept or Topic Maps have long been used as a method of categorizing and organizing information about a domain. Building them can help people conceptualize an area and spot trends or gaps, and as a presentation method they quickly provide an overview and general impression of a space. We are currently constructing a Reference Model of the Assessment Domain that takes the form of a highly interlinked dynamic website. This represents the assessment domain via the software, projects, standards and use cases of which it is composed. In this paper we present our efforts to create complimentary concept maps of the assessment domain, not as an overview, but for navigation and orientation within the domain. These concept maps, which model resources and activities independently, have been corroborated with practitioners in the e-learning community

Technology Adoption And Pest Control Strategies Among UK Cereal Farmers: Evidence from Parametric and Nonparametric Count Data Models

This paper examines technology adoption and integrated pest management strategies employed by UK farmers, using both parametric and nonparametric methods. We employ a unique survey data set collected from UK cereal farmers to assess the determinants of technology adoption in relation to pest management. Our preferred model specification is nonparametric which makes use of the recently developed methods of Li and Racine (2007) and Racine and Li (2004). These methods allow us to combine categorical and continuous data and thereby avoid sample splitting and resulting efficiency losses. Our analysis reveals that total area farmed is positively related to the number of technologies adopted, whereas age is negatively related. We also find evidence of significant statistical differences for number of adoptions by region across the UK

AGB Sodium Abundances in the Globular Cluster 47 Tucanae (NGC 104)

A recent analysis comparing the [Na/Fe] distributions of red giant branch (RGB) and asymptotic giant branch (AGB) stars in the Galactic globular cluster NGC 6752 found that the ratio of Na-poor to Na-rich stars changes from 30:70 on the RGB to 100:0 on the AGB. The surprising paucity of Na-rich stars on the AGB in NGC 6752 warrants additional investigations to determine if the failure of a significant fraction of stars to ascend the AGB is an attribute common to all globular clusters. Therefore, we present radial velocities, [Fe/H], and [Na/Fe] abundances for 35 AGB stars in the Galactic globular cluster 47 Tucanae (47 Tuc; NGC 104), and compare the AGB [Na/Fe] distribution with a similar RGB sample published previously. The abundances and velocities were derived from high resolution spectra obtained with the Michigan/Magellan Fiber System (M2FS) and MSpec spectrograph on the Magellan-Clay 6.5m telescope. We find the average heliocentric radial velocity and [Fe/H] values to be =-18.56 km s^-1 (sigma=10.21 km s^-1) and =-0.68 (sigma=0.08), respectively, in agreement with previous literature estimates. The average [Na/Fe] abundance is 0.12 dex lower in the 47 Tuc AGB sample compared to the RGB sample, and the ratio of Na-poor to Na-rich stars is 63:37 on the AGB and 45:55 on the RGB. However, in contrast to NGC 6752, the two 47 Tuc populations have nearly identical [Na/Fe] dispersion and interquartile range values. The data presented here suggest that only a small fraction <20% of Na-rich stars in 47 Tuc may fail to ascend the AGB. Regardless of the cause for the lower average [Na/Fe] abundance in AGB stars, we find that Na-poor stars and at least some Na-rich stars in 47 Tuc evolve through the early AGB phase. [abridged]Comment: Accepted for publication in the Astronomical Journal; 15 pages; 8 figures; 4 table