We introduce uncertainty about farmer characteristics into the moral hazard problem facing a regulator offering agri-environmental contracts. Our model allows for a continuum of farmer compliance costs. For reasonable parameter values the model predicts high levels of cheating and intensive monitoring, contrary to the evidence. We therefore add variation in farmers’ propensity to cheat, the reg...

While the conditions that favour the maintenance of cooperation have been extensively investigated, the significance of non-social selection pressures on social behaviours has received little attention. In the absence of non-social selection pressures, patches of cooperators are vulnerable to invasion by cheats. However, we show both theoretically, and experimentally with the bacterium Pseudomo...

Understanding how soil respiration (Rs) and its source components respond to climate warming is crucial to improve model prediction of climate-carbon (C) feedback. We conducted a manipulation experiment by warming and clipping in a prairie dominated by invasive winter annual Bromus japonicas in Southern Great Plains, USA. Infrared radiators were used to simulate climate warming by 3 °C and clip...

Prairie grasslands are very species rich but have declined in their extent considerably due to landuse change and exploitation. Many remaining prairie fragments are situated within an agricultural matrix and can be subjected to high levels of atmospheric ammonia deposition from animal units. Three prairie fragments in Minnesota that were located in close proximity to feedlots were selected, and...

Distribution data for the Evanioidea are taken from Crosskey (1951), with additional references given under notes for each taxon. This is a small superfamily of three extant families, but particularly poorly represented in northern Europe. The Evaniidae (sometimes referred to as 'ensign wasps') are, where known, parasitoids/predators of cockroach oothecae (Crosskey 1951; Brown 1973) and are mor...

In multilateral enforcement, a player who cheats on one partner is punished by many partners. But renegotiation might subvert the threat of multilateral punishment. We consider renegotiation proofness in multilateral enforcement games with public monitoring, and also introduce the notion of “bilateral renegotiation proofness” for games with private monitoring. With public monitoring, renegotiat...

Comparisons of vegetation dynamics of riparian plant communities under livestock use and esclusions over a 10 year period were quantified in a Northeastern Oregon riparian zone. We measured species frequency, richness, diversity, evenness, and livestock utilization in 8 plant communities. Livestock grazed the study area from late August until mid September at a rate of 1.3 to 1.8 ha/AUM. Utiliz...

Advances in electron cryo-microscopy have enabled structure determination of macromolecules at near-atomic resolution. However, structure determination, even using de novo methods, remains susceptible to model bias and overfitting. Here we describe a complete workflow for data acquisition, image processing, all-atom modelling and validation of brome mosaic virus, an RNA virus. Data were collect...

Substantial questions remain about the time required for groundwater nitrate to be reduced below 10 mg L(-1) following establishment of vegetated riparian buffers. The objective of this study was to document changes in groundwater nitrate-nitrogen (NO3-N) concentrations that occurred within a few years of planting a riparian buffer. In 2000 and 2001 a buffer was planted adjacent to a first-orde...