David B. Field results 29
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Conservation benefits of a large marine protected area network that spans multiple ecosystemsNARA Subscribed
Marine protected areas (MPAs) are widely implemented tools for long‐term ocean conservation and resource management. Assessments of MPA performance have largely focused on specific ecosystems individually and have rarely evaluated performance across multiple ecosystems either in an individual MPA or across an MPA network. We evaluated the conservation performance of 59 MPAs in California's large MPA network, which encompasses...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Snapshot isolation and isolation history challenge the analogy between mountains and islands used to understand endemismNARA Subscribed
Aim Mountains and islands are both well known for their high endemism. To explain this similarity, parallels have been drawn between the insularity of “true islands” (land surrounded by water) and the isolation of habitats within mountains (so‐called “mountain islands”). However, parallels rarely go much beyond the observation that mountaintops are isolated from one another, as are true islands. Here, we challenge the analogy...
Topography‐driven isolation, speciation and a global increase of endemism with elevationNARA Subscribed
Aim Higher‐elevation areas on islands and continental mountains tend to be separated by longer distances, predicting higher endemism at higher elevations; our study is the first to test the generality of the predicted pattern. We also compare it empirically with contrasting expectations from hypotheses invoking higher speciation with area, temperature and species richness. Location Thirty‐two insular and 18 continental elevati...
Weighing the Evidence of Common Beliefs in Obesity ResearchNARA Subscribed
Climate extremes in California agricultureNARA Subscribed
Greenhouse gas, upwelling‐favorable winds, and the future of coastal ocean upwelling ecosystemsNARA Subscribed
Coastal ocean upwelling ecosystems generally represent the most productive large marine ecosystems of the world's oceans, in terms of both primary production rates and tonnages of exploitable fish produced. The Peruvian upwelling system, in particular, stands out as a major factor in world fish production. The Pacific trade winds have traditionally been considered to be the primary driving force for the upwelling system off Pe...
Tradeoffs among Ecosystem Benefits: An Analysis Framework in the Evaluation of Forest Management AlternativesNARA Subscribed
This article presents an analysis framework to develop and compare forest management alternatives by quantifying the tradeoffs among several forest ecosystem benefits. First, we present a modeling environment that estimates future outcomes simulated over a period of time given a set of management goals, existing laws and regulations, and the capacity of the forest ecosystem to provide quantified forest ecosystem values. This e...
Relationship of predation potential to mortality of Calanus finmarchicus on Georges Bank, northwest AtlanticNARA Subscribed
Based on 29 cruises on Georges Bank between January and June, conducted as part of the U.S. Global Ocean Ecosystem Dynamics program, we describe seasonal and spatial variability of early life history mortality for the planktonic copepod Calanus finmarchicus and relate mortality to an index of predation potential from a suite of suspension‐feeding predators. Emphasis is placed on the earliest life history phase wherein peak mor...
Estimation of the carbon dioxide (CO 2 ) fertilization effect using growth rate anomalies of CO 2 and crop yields since 1961NARA Subscribed
The effect of elevated carbon dioxide (CO 2 ) on crop yields is one of the most uncertain and influential parameters in models used to assess climate change impacts and adaptations. A primary reason for this uncertainty is the limited availability of experimental data on CO 2 responses for crops grown under typical field conditions. However, because of historical variations in CO 2 , each year farmers throughout the world perf...