Quantifying the risk of non‐native conifer establishment across heterogeneous landscapes

1. Pines (genus Pinus) are cultivated extensively for forestry purposes, particularly in regions that are outside the genus' native range. The most common forestry species are also typically those most likely to escape cultivation and spread rapidly, and thus pines constitute a substantial weed problem in many regions. However, there is limited knowledge of the factors underlying the spread of pines from plantations. Assessments across heterogeneous landscapes are required to provide rigorous data to support management tools and policies aiming to protect vulnerable ecosystems from pine invasions. 2. We examined the spread of Pinus radiata from forestry plantations over a ~9,000 km² landscape on Banks Peninsula, New Zealand. We used ground-based surveys from a set of viewpoints to determine tree locations, coupled with geographical information system (GIS) viewsheds to define the area surveyed. We used boosted regression trees to build a habitat model for P. radiata establishment on Banks Peninsula. 3. We surveyed an area approximately 107 km², recording 470 naturally established P. radiata individuals. Our habitat models suggested that proximity to the nearest plantation forest was the most important variable predicting P. radiata establishment, with individuals most likely to establish within 150 m of a plantation. Individuals were also most likely to establish in early successional shrub communities, proximate to roads, and on steeper topography. Highly grazed habitats were least vulnerable to P. radiata establishment. 4. The slope and aspect of the source plantation influenced the distances from the plantation at which P. radiata individuals were recorded, with individuals recorded furthest away likely to have originated from plantations that were south-facing or on steeper slopes, and therefore most exposed to strong winds. 5. Synthesis and applications. Our findings on distances from plantations at which individuals established, vulnerable habitats, and the interactions we detected among our predictor variables, can be extended to aid management of non-native conifer plantings elsewhere in the Southern Hemisphere. These data can be used to contribute to improvements of decision support systems that assess likely spread risk from non-native conifer plantings. Such tools can reduce the likelihood of future pine establishment, potentially preventing biological invasions

Combining laser rangefinder and viewshed technologies to improve ground surveys of invasive tree distributions

1. Quantifying the spatial extent, location and habitat associations of invasive tree species is critical to predict their future spread and prioritise areas for management. Species–environment relationship analyses are useful tools for understanding and predicting the potential geographical distribution of these species; however, such tools require rigorous and extensive data about species presence and, crucially, the area surveyed. 2. Here, we describe a method for performing ground-based visual surveys of invasive trees from a set of viewpoints that utilises laser rangefinder and global navigation satellite system (GNSS) technology to detect tree locations. We then highlight the novel use of geographical information system (GIS) viewsheds as a tool to define the area surveyed. 3. Using the invasive conifer, Pinus radiata, as our target, we undertook a ground-truthing exercise for 50 trees established in the wild to assess the accuracy of the method and determine the suitable spatial resolution for GIS data that would be used in subsequent species–environment relationship analyses. For these trees, location error was positively related to distance from the tree to the viewpoint. The calculated locations for all trees within 600 m of the observer were within 25 m of the location as determined by the GNSS unit, with a median location error of 4 m. These results indicate that data of a resolution suitable for mapping invasive trees can be efficiently collected over large areas. We also outline suggestions and instructions for computing the viewsheds to determine the surveyed area. 4. This approach allows for efficient collection of accurate data on the occurrence of non-native trees and the land area surveyed. These data can underpin species–environment relationship analyses that then form the basis of risk maps for areas prone to future invasion. Given the speed and accuracy with which data can be obtained using this method, and the use of standard and easily accessible field equipment and GIS software, we recommend this approach to other spatial and invasion ecologists

Sleep-wake sensitive mechanisms of adenosine release in the basal forebrain of rodents : an in vitro study

Adenosine acting in the basal forebrain is a key mediator of sleep homeostasis. Extracellular adenosine concentrations increase during wakefulness, especially during prolonged wakefulness and lead to increased sleep pressure and subsequent rebound sleep. The release of endogenous adenosine during the sleep-wake cycle has mainly been studied in vivo with microdialysis techniques. The biochemical changes that accompany sleep-wake status may be preserved in vitro. We have therefore used adenosine-sensitive biosensors in slices of the basal forebrain (BFB) to study both depolarization-evoked adenosine release and the steady state adenosine tone in rats, mice and hamsters. Adenosine release was evoked by high K+, AMPA, NMDA and mGlu receptor agonists, but not by other transmitters associated with wakefulness such as orexin, histamine or neurotensin. Evoked and basal adenosine release in the BFB in vitro exhibited three key features: the magnitude of each varied systematically with the diurnal time at which the animal was sacrificed; sleep deprivation prior to sacrifice greatly increased both evoked adenosine release and the basal tone; and the enhancement of evoked adenosine release and basal tone resulting from sleep deprivation was reversed by the inducible nitric oxide synthase (iNOS) inhibitor, 1400 W. These data indicate that characteristics of adenosine release recorded in the BFB in vitro reflect those that have been linked in vivo to the homeostatic control of sleep. Our results provide methodologically independent support for a key role for induction of iNOS as a trigger for enhanced adenosine release following sleep deprivation and suggest that this induction may constitute a biochemical memory of this state

The Role of Individual Variables, Organizational Variables and Moral Intensity Dimensions in Libyan Management Accountants’ Ethical Decision Making

This study investigates the association of a broad set of variables with the ethical decision making of management accountants in Libya. Adopting a cross-sectional methodology, a questionnaire including four different ethical scenarios was used to gather data from 229 participants. For each scenario, ethical decision making was examined in terms of the recognition, judgment and intention stages of Rest’s model. A significant relationship was found between ethical recognition and ethical judgment and also between ethical judgment and ethical intention, but ethical recognition did not significantly predict ethical intention—thus providing support for Rest’s model. Organizational variables, age and educational level yielded few significant results. The lack of significance for codes of ethics might reflect their relative lack of development in Libya, in which case Libyan companies should pay attention to their content and how they are supported, especially in the light of the under-development of the accounting profession in Libya. Few significant results were also found for gender, but where they were found, males showed more ethical characteristics than females. This unusual result reinforces the dangers of gender stereotyping in business. Personal moral philosophy and moral intensity dimensions were generally found to be significant predictors of the three stages of ethical decision making studied. One implication of this is to give more attention to ethics in accounting education, making the connections between accounting practice and (in Libya) Islam. Overall, this study not only adds to the available empirical evidence on factors affecting ethical decision making, notably examining three stages of Rest’s model, but also offers rare insights into the ethical views of practising management accountants and provides a benchmark for future studies of ethical decision making in Muslim majority countries and other parts of the developing world

The influence of habitat structure on genetic differentiation in red fox populations in north-eastern Poland

The red fox (Vulpes vulpes) has the widest global distribution among terrestrial carnivore species, occupying most of the Northern Hemisphere in its native range. Because it carries diseases that can be transmitted to humans and domestic animals, it is important to gather information about their movements and dispersal in their natural habitat but it is difficult to do so at a broad scale with trapping and telemetry. In this study, we have described the genetic diversity and structure of red fox populations in six areas of north-eastern Poland, based on samples collected from 2002–2003. We tested 22 microsatellite loci isolated from the dog and the red fox genome to select a panel of nine polymorphic loci suitable for this study. Genetic differentiation between the six studied populations was low to moderate and analysis in Structure revealed a panmictic population in the region. Spatial autocorrelation among all individuals showed a pattern of decreasing relatedness with increasing distance and this was not significantly negative until 93 km, indicating a pattern of isolation-by-distance over a large area. However, there was no correlation between genetic distance and either Euclidean distance or least-cost path distance at the population level. There was a significant relationship between genetic distance and the proportion of large forests and water along the Euclidean distances. These types of habitats may influence dispersal paths taken by red foxes, which is useful information in terms of wildlife disease management

Potential adaptive strategies for 29 Sub-Saharan crops under future climate change

Climate change is expected to severely impact cultivated plants and consequently human livelihoods especially in sub-Saharan Africa (SSA). Increasing agricultural plant diversity (agrobiodiversity) could overcome this global challenge given more information on the climatic tolerance of crops and their wild relatives. Using >200,000 worldwide occurrence records for 29 major crops and 778 of their wild relative species, we assess, for each crop, how future climatic conditions are expected to change in SSA and whether populations of the same crop from other continents, wild relatives around the world or other crops from SSA are better adapted to expected future climatic conditions in the region. We show that climate conditions not currently experienced by the 29 crops in SSA are predicted to become widespread, increasing production insecurity, especially for yams. However, crops such as potato, squash and finger millet may be maintained by using wild relatives or non-African crop populations with climatic niches more suited to future conditions. Crop insecurity increases over time and with rising GHG emissions, but the potential for using agrobiodiversity for resilience is less altered. Climate change will therefore affect sub-Saharan agriculture but agrobiodiversity can provide resilient solutions in the short and medium term