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The rise of “the rest,” especially China, has triggered an inevitable transformation of the so-called liberal international order. Rising powers have started to both challenge and push for the reform of existing multilateral institutions, such as the International Monetary Fund (IMF), and to create new ones, such as the Asian Infrastructure Investment Bank (AIIB). The United States under the Trump administration, on the other hand, has retreated from the international institutions that the country once led or helped to create, including the Trans-Pacific Partnership (TPP); the Paris Agreement; the Iran nuclear deal; the Intermediate-Range Nuclear Forces (INF) Treaty; the United Nations Educational, Scientific and Cultural Organization (UNESCO); and the United Nations Human Rights Council (UNHRC). The United States has also paralyzed the ability of the World Trade Organization (WTO) to settle trade disputes by blocking the appointment of judges to its appellate body. Moreover, in May 2020, President Trump announced his decision to quit the Open Skies Treaty, an arms control regime designed to promote transparency among its members regarding military activities. During the past decade or so, both Russia and the United States have been dismantling multilateral arms control treaties one by one while engaging in new nuclear buildups at home.
Drawing upon new evidence emerging from Kenya's Cherangani Hills, this research project furthers current understanding of the archaeology of Late Iron Age forest-dwelling communities in East Africa, focusing on a series of intriguing earthworks deep inside forest environments that are reminiscent of the ‘Sirikwa’ tradition.
The English auxiliary system exhibits many lexical exceptions and subregularities, and considerable dialectal variation, all of which are frequently omitted from generative analyses and discussions. This paper presents a detailed, movement-free account of the English Auxiliary System within Sign-Based Construction Grammar (Sag 2010, Michaelis 2011, Boas & Sag 2012) that utilizes techniques of lexicalist and construction-based analysis. The resulting conception of linguistic knowledge involves constraints that license hierarchical structures directly (as in context-free grammar), rather than by appeal to mappings over such structures. This allows English auxiliaries to be modeled as a class of verbs whose behavior is governed by general and class-specific constraints. Central to this account is a novel use of the feature aux, which is set both constructionally and lexically, allowing for a complex interplay between various grammatical constraints that captures a wide range of exceptional patterns, most notably the vexing distribution of unstressed do, and the fact that Ellipsis can interact with other aspects of the analysis to produce the feeding and blocking relations that are needed to generate the complex facts of EAS. The present approach, superior both descriptively and theoretically to existing transformational approaches, also serves to undermine views of the biology of language and acquisition such as Berwick et al. (2011), which are centered on mappings that manipulate hierarchical phrase structures in a structure-dependent fashion.
The unprecedented Ebola Virus Disease (EVD) outbreak in West Africa, with its first cases documented in March 2014, has claimed the lives of thousands of people, and it has devastated the health care infrastructure and workforce in affected countries. Throughout this outbreak, there has been a critical lack of health care workers (HCW), including physicians, nurses, and other essential non-clinical staff, who have been needed, in most of the affected countries, to support the medical response to EVD, to attend to the health care needs of the population overall, and to be trained effectively in infection protection and control. This lack of sufficient and qualified HCW is due in large part to three factors: 1) limited HCW staff prior to the outbreak, 2) disproportionate illness and death among HCWs caused by EVD directly, and 3) valid concerns about personal safety among international HCWs who are considering responding to the affected areas. These guidelines are meant to inform institutions who deploy professional HCWs. (Disaster Med Public Health Preparedness. 2015;9:586–590)
The term “seaweed” traditionally includes only macroscopic, multicellular marine red, green, and brown algae. However, each of these groups has microscopic, if not unicellular, representatives. All seaweeds at some stage in their life cycles are unicellular, as spores or gametes and zygotes, and may be temporarily planktonic (Amsler and Searles 1980; Maximova and Sazhin 2010). Some remain small, forming sparse but productive turfs on coral reefs (Hackney et al. 1989) while others, such as the “kelps” of temperate reefs, can form extensive underwater forests (Graham et al. 2007a). Siphonous algae such as Codium, Caulerpa and Bryopsis that form large thalli are, in fact, acellular. The prokaryotic Cyanobacteria have occasionally been acknowledged in “seaweed” floras (e.g. Setchell and Gardner 1919; Littler and Littler 2011a). They are widespread on temperate rocky and sandy shores (Whitton and Potts 1982) and are particularly important in the tropics, where large macroscopic tufts of Oscillatoriaceae and smaller but abundant nitrogen-fixing Nostocaceae are major components of the reef flora (Littler and Littler 2011a, b; Charpy et al. 2012). Benthic diatoms also form large and sometimes abundant tube-dwelling colonies that resemble seaweeds (Lobban 1989). An ancient lineage of (mostly) deep-water green algae, the Palmophyllales, that includes Verdigellas and Palmophyllum, have a palmelloid organization with complex thalli built from an amorphous matrix with a nearly uniform distribution of spherical cells (Womersley 1971; Zechman et al. 2010). On a smaller scale are the colonial filaments of some simple red algae, such as Stylonema (previously Goniotrichum). A “seaweed” is therefore problematic to precisely define: here “seaweed” refers to algae from the red, green, and brown lineages that, at some stage of their life cycle, form multicellular or siphonous macrothalli. In this book we shall consider macroscopic and microscopic marine benthic environments and how seaweeds respond to those environments.
The waters of the oceans are in constant motion. The causes of that motion are many, beginning with the great ocean currents, tidal currents, waves, and other forces, and ranging down to the small-scale circulation patterns caused by local density changes (Vogel 1994; Thurman and Trujillo 2004). Hydrodynamic force is a direct environmental factor, but water motion also affects other factors, including nutrient availability, light penetration, and temperature and salinity changes. The forces embodied in waves are difficult to comprehend, unless one has been dangerously close to them; because of the density of water, a wave or current exerts much more force than do the winds. “Imagine a human foraging for food and searching for a mate in a hurricane and you will have only an inkling of the physical constraints imposed on wave-swept life” (Patterson 1989b, p. 1374). The energy amassed from a great expanse of air–ocean interactions is expended on the shoreline as waves break (Leigh et al. 1987). Equally difficult to visualize are the microscopic layers of water next to seaweed surfaces where the seaweeds’ cells interact with water. Too much water motion imposes drag forces that can rip seaweeds from the rocks, but this also clears patches of “new” space for recruitment. Too little water motion and nutrient concentration gradients form at the seaweed surface which can restrict nutrient uptake, but the same gradients are used by seaweeds to sense how fast the surrounding seawater is moving and thereby cue gamete or spore release.
Studies of seaweed form and function in wave-exposed and wave-protected sites have provided insights into the trade-offs apparent in some species that allow them to maximize resource acquisition in slow flows and minimize drag forces in fast flows. The following texts and reviews provide the necessary background on fluid mechanics: Denny (1988, 1993, 2006); Vogel (1994); Denny and Wethey (2001). “Marine ecomechanics” is an emerging field that uses a “physical framework” to understand the responses of marine organisms on scales from cells to ecosystems (Denny and Helmuth 2009; Denny and Gaylord 2010). We begin this chapter by describing the hydrodynamic environments in which seaweeds grow, and then discuss the mechanisms by which seaweeds can enhance resource acquisition in slow flows and withstand hydrodynamic forces in wave-exposed sites. We finish with a discussion on the effects of wave action and sediments on seaweed communities.
The environment of an organism includes both biotic and abiotic (physiochemical) factors. Communities of marine organisms encompass not only the seaweed communities but also the animal communities, of which the benthic grazers and their predators are most important to seaweed ecology. Thus, the biotic interactions of seaweeds include not only competition with other seaweeds (both within and between species) and with sessile animals but also predator–prey relations at several trophic levels, and facilitation; the mix of such interactions will change as the individual changes with age and environmental history.
Biotic interactions are complex, and their study often requires large-scale and long-term observations and manipulations in the laboratory, as well as in the field. Interactions can be positive (e.g. facilitation, mutualism, and commensalism), negative (e.g. competitive exclusion, consumption) or neutral, where there is no effect of one species on another. Studies on biotic interactions in the marine environment have traditionally focused on competition but more recently facilitation has been recognized as an important way in which biota interact. The minireviews of Olson and Lubchenco (1990), Carpenter (1990), Paine (1990), and Maggs and Cheney (1990) remain useful frameworks, as are the more recent syntheses found within Marine Community Ecology (Bertness et al. 2001) and Marine Ecology (Connell and Gillanders 2007).
As seaweed consumption has increased in the last several decades, seaweed mariculture has filled the gap between wild stock harvest and the present demand. Ancient records show that people collected seaweeds for food starting in about 2500 BP in China (Tseng 1981), and 1500 in Europe (Critchley and Ohno 1998). Presently, the wild harvest of seaweeds is about 1.8 m tonnes y-1, mainly brown seaweeds used for alginates (FAO 2009). In Japan, China, and other Asian countries, where seaweeds have long composed an important part of the human diet, seaweed farming is a major business and over 90% of the seaweed production is from farming for human consumption. Since 1970, the culture of seaweeds has increased at ~8% per year (FAO 2009). Seaweed production from farming nearly doubled from 8.8 to 15.9 million tonnes from 1999 to 2008, with a value of US$7.4 billion (FAO 2010). Most of the world seaweed supply comes from aquaculture and seaweeds were the first to pass the 50% farmed/wild harvest threshold in 1971, compared to fish aquaculture that will exceed the 50% threshold by 2012 (Chopin 2012). About 99% of the farmed production is in Asia and over 70% of the production (10.9 million tonnes) is in China, followed by Indonesia, the Philippines, South Korea, and Japan. Chile is the most important producer outside of Asia with a production of 90 000 tonnes y-1 of wild harvested seaweeds. Table 10.1 illustrates the production, value, price and the three main producing countries for the six most important seaweed genera that are grown in aquaculture systems. Brown seaweeds compose about 64% of the production (67% of the value), reds about 36% (33% of the value), and greens, with ~99% being produced by Asian countries, 0.2% of the production and value (Chopin and Sawhney 2009). There has been a rapid increase in production in the last decade, especially of reds and browns (Fig. 10.1). The largest production (4.6 million tonnes; Table 10.1) is from Saccharina japonica (previously Laminaria japonica; or kombu in Japan or haidai in China), mainly in China. Korea grows mainly Undaria pinnatifida (wakame) with 1.8 million tonnes annually and Pyropia (previously Porphyra, or nori), while Japan focuses mainly on Pyropia.
Seaweeds exist as individuals, but they also live together in communities with other seaweeds and animals – communities that affect and are affected by the environment. Ecologists and physiologists alike are drawn to coastal marine ecosystems because of the easy access to strong environmental gradients over short spatial scales. Marine organisms grow in often distinctive vertical or horizontal “zones” or “bands” along these gradients, thereby providing “natural laboratories” in which to study environmental (abiotic) and biological processes shaping the communities. Zones of vegetation are also found in terrestrial habitats, but here the spatial scales are typically much greater. On a mountain, for example, vegetation is zoned with altitude, but the vertical distance over which changes occur can be in the order of 1000 m rather than several meters in the intertidal zone (Raffaelli and Hawkins 1996). Vertical gradients in the intertidal are easily observed at low tide, but also extend underwater where the surface irradiance can be reduced to 1% at 15 m depth in many coastal waters (Lüning and Dring 1979; sec. 5.2.2). Horizontal gradients include the salinity gradients of estuaries and salt marshes, and wave exposure (Raffaelli and Hawkins 1996).
In Chapters 1 and 2, we reviewed the morphologies, life histories, and developmental processes of seaweeds as species. In this chapter we consider the patterns and processes in marine benthic communities as a starting point for later factor-by-factor dissection of the environment. We open with an overview of zonation patterns seen in the intertidal and subtidal environments.