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Does scale matter? A systematic review of incorporating biological realism when predicting changes in species distributions
Get PDFBackground
There is ample evidence that biotic factors, such as biotic interactions and dispersal capacity, can affect species distributions and influence species’ responses to climate change. However, little is known about how these factors affect predictions from species distribution models (SDMs) with respect to spatial grain and extent of the models.
Objectives
Understanding how spatial scale influences the effects of biological processes in SDMs is important because SDMs are one of the primary tools used by conservation biologists to assess biodiversity impacts of climate change.
Data sources and study eligibility criteria
We systematically reviewed SDM studies published from 2003–2015 using ISI Web of Science searches to: (1) determine the current state and key knowledge gaps of SDMs that incorporate biotic interactions and dispersal; and (2) understand how choice of spatial scale may alter the influence of biological processes on SDM predictions.
Synthesis methods and limitations
We used linear mixed effects models to examine how predictions from SDMs changed in response to the effects of spatial scale, dispersal, and biotic interactions.
Results
There were important biases in studies including an emphasis on terrestrial ecosystems in northern latitudes and little representation of aquatic ecosystems. Our results suggest that neither spatial extent nor grain influence projected climate-induced changes in species ranges when SDMs include dispersal or biotic interactions.
Conclusions
We identified several knowledge gaps and suggest that SDM studies forecasting the effects of climate change should: 1) address broader ranges of taxa and locations; and 1) report the grain size, extent, and results with and without biological complexity. The spatial scale of analysis in SDMs did not affect estimates of projected range shifts with dispersal and biotic interactions. However, the lack of reporting on results with and without biological complexity precluded many studies from our analysis
Promoting Student Partnership in a Postgraduate Environmental Management Programme Through Thesis Research and Writing Workshops
Get PDFType Variables in Patterns
Get PDFFor many years, GHC has implemented an extension to Haskell that allows type variables to be bound in type signatures and patterns, and to scope over terms. This extension was never properly specified. We rectify that oversight here. With the formal specification in hand, the otherwise-labyrinthine path toward a design for binding type variables in patterns becomes blindingly clear. We thus extend ScopedTypeVariables to bind type variables explicitly, obviating the Proxy workaround to the dustbin of history
Thinking About the \u27Ming China\u27 Anew: The Ethnocultural Space In A Diverse Empire-With Special Reference to the \u27Miao Territory\u27
Get PDFBy examining the cultural identity of China\u27s Ming dynasty, this essay challenges two prevalent perceptions of the Ming in existing literature: to presume a monolithic socio-ethno-cultural Chinese empire and to equate the Ming Empire with China (Zhongguo, the “middle kingdom”). It shows that the Ming constructed China as an ethnocultural space rather than a political entity. In essence, China was defined as a Han domain that the Han people inhabited and where Han values were produced, practiced, and preserved in contrast to those of non-Han “barbarians,” be they domestic or foreign. The “Great Ming”—the dynastic title—cannot be confused with China, the ethnocultural space. For the Ming ruling elite, the “Miao territory” in western Huguang and eastern Guizhou provinces represented a land “beyond the pale of civilization” (huawai), which was outside and different from China. The Ming construction of the ethnocultural China connects the imperial heritage to China\u27s modern identity
Explaining homegrown Western jihadists: The importance of Western foreign policy
Get PDFIn both the United States and Europe, explanations of homegrown radicalization emphasize the power of Salafi-jihadist ideology and Muslim experiences of discrimination and socioeconomic deprivation in Western countries. Polls of U.S. and European Muslims, and case histories of jihadist plots for attacks in the United States, indicate that another source of homegrown radicalization is Western foreign policy, especially Western interventions in predominantly Muslim countries. Poll results support a two-factor model in which seeing the war on terrorism as a war on Islam is predicted by both perceived discrimination and grievance related to Western foreign policy. Consistent with this model, UK practitioners in counter-radicalization programs find it useful to recognize Muslim grievances related to Western foreign policy in order to argue that violence does not reduce Muslim suffering. These observations indicate that Muslim grievances relating to Western foreign policy are important for understanding and countering support for jihadist violence in Western countries
Mobile but Stuck: Multigenerational Neighborhood Decline and Housing Search Strategies for African Americans
Get PDFWhile many scholars have demonstrated that entrenched racial residential segregation perpetuates racial inequality, the causes of persistent racial segregation continue to be debated. This paper investigates how geographically and socioeconomically mobile African Americans approach the home-buying process in the context of a segregated metropolitan region, by using qualitative interviews with working-class to middle-income African American aspiring homebuyers. Homebuyers use three principal search strategies to determine suitable neighborhoods: avoiding decline, searching for improvement, and searching for stability. The findings suggest that despite these strategies African American homebuyers end up in areas that may not retain characteristics they desire in terms of racial demographics and amenities, in large part because such neighborhoods remain rare
The Distorted Images and Realities of Andrei Bitov’s Literary Photographs.
Get PDFAlthough Andrei Bitov’s best-known exploration of photography remains “Pushkin’s Photograph (1799–2099),” in which a young Pushkinist travels into the past to capture the poet’s image on film, this motif in fact appears throughout many of the author’s major works. This study addresses the two conflicting stances regarding photography that Bitov develops across a variety of genres. On the one hand, the manner in which a photo attempts to freeze or distort reality according to a particular worldview deeply disturbs his narrators, both fictional and semi-autobiographical. It becomes a tool for manipulation in texts such as “View of the Trojan Sky” from The Symmetry Teacher, Pushkin House, A Georgian Album, and Armenia Lessons. On the other hand, photography can preserve personal and cultural memory, as seen in works including Pushkin House and A Georgian Album, and offer alternative viewpoints that expand one’s knowledge (Birds, Man in the Landscape). An analysis of the understudied tensions between these two perspectives will better reveal how Bitov deploys his photographic trope in order to probe key themes such as identity, man’s relationship to history and other individuals, epistemological uncertainty, and the fluid connection between reality and simulation
Implications of Pyran Cyclization and Pterin Conformation on Oxidized Forms of the Molybdenum Cofactor
Get PDFThe large family of mononuclear molybdenum and tungsten enzymes all possess the special ligand molybdopterin (MPT), which consists of a metal-binding dithiolene chelate covalently bound to a pyranopterin group. MPT pyran cyclization/scission processes have been proposed to modulate the reactivity of the metal center during catalysis. We have designed several small-molecule models for the Mo-MPT cofactor that allow detailed investigation into how pyran cyclization modulates electronic communication between the dithiolene and pterin moieties and how this cyclization alters the electronic environment of the molybdenum catalytic site. Using a combination of cyclic voltammetry, vibrational spectroscopy (FT-IR and rR), electronic absorption spectroscopy, and X-ray absorption spectroscopy, distinct changes in the Mo≡O stretching frequency, Mo(V/IV) reduction potential, and electronic structure across the pterin-dithiolene ligand are observed as a function of pyran ring closure. The results are significant, for they reveal that a dihydropyranopterin is electronically coupled into the Mo-dithiolene group due to a coplanar conformation of the pterin and dithiolene units, providing a mechanism for the electron-deficient pterin to modulate the Mo environment. A spectroscopic signature identified for the dihydropyranopterin-dithiolene ligand on Mo is a strong dithiolene → pterin charge transfer transition. In the absence of a pyran group bridge between pterin and dithiolene, the pterin rotates out of plane, largely decoupling the system. The results support a hypothesis that pyran cyclization/scission processes in MPT may function as a molecular switch to electronically couple and decouple the pterin and dithiolene to adjust the redox properties in certain pyranopterin molybdenum enzymes
