COLLECTION OF SAMPLES

This chapter emphasizes only those techniques that are pertinent to unconsolidated sediments, and essentially applicable to both foraminifera and thecamoebians. The collection and processing of hard-rock samples is rarely necessary for contemporary environmental impact evaluations. For further information on hard-rock processing, readers are referred to papers by Wightman et al. (1994), Thomas and Murney (1981), or any of the many papers dealing with microfossils in shale or sandstone.

Methods of sampling testate rhizopods are greatly facilitated by the small size and abundance of these shelled protozoans. However, because of the need to ensure that the upper several centimeters of sediment remain undisturbed during the collection process, a variety of sampling methods have been developed over the years.

Surface Samples

Most conventional spatial surveys rely on one of several types of grab samplers. Selecting a particular model is influenced by project goals and logistical and sample quality considerations. For nearshore environments that are being accessed using small craft, the 15 × 15 cm Ekman dredge sampler provides a good-quality small-surface (10 × 10 cm) sample. The closing mechanism of this device is triggered by a weight that is released at the surface after the sampler has “landed” on the seafloor. The weight slides down the hauling rope and strikes a plate that releases the spring-loaded sampler jaws (Fig. 2.1).

This chapter is intended to facilitate an understanding of how foraminifera and thecamoebians can help in evaluating marine-related environmental questions. Many of the diagrams presented have been simplified from the original for demonstrative purposes.

SEA-LEVEL CHANGES

Definitive Assemblages

Many workers have used foraminifera as sea-level indicators (see Haynes, 1981, for a review) but, prior to 1976, their resolution was limited to plus or minus several meters, especially if offshore assemblages were used. The assemblages described here should provide an accuracy of plus or minus a few centimeters at best, and 50 cm at worst. In 1976, the absolute accuracy of salt marsh foraminiferal vertical zonations was verified in southern California (Scott, 1976a) and later compared on a worldwide scale (Scott and Medioli, 1978, 1980b). Since that time, much more work has been done to verify that the relationship exists everywhere (e.g., Petrucci et al., 1983; Patterson, 1990; D. K. Scott and Leckie, 1990; Jennings and Nelson, 1992; Gehrels, 1994; deRijk, 1995; Horton et al., 1999a,b). It appears that the same eight to ten species of marsh foraminifera are ubiquitous throughout the world's salt marshes, especially in the upper half of the marsh. The reason salt marshes in general, and marsh foraminiferal zones in particular, have been used widely for sea-level studies is that the entire marsh environment is confined to the upper half of the tidal range (Chapman, 1960). For most tidal ranges this means that the whole vertical range of the salt marsh deposit is 1 meter or less.

Methods to detect and monitor environmental change using indigenous species are in demand more and more each day as they become recognized as important tools in resource management and in situ monitoring (e.g., Goldberg, 1998). The benthic foraminifera continue to emerge as an important and unique type of indicator organism. As was illustrated in Chapter 3, they are abundant, provide statistically significant populations in small samples, have rapid reproductive cycles, are preserved as fossils, and have many types of applications to monitoring programs. This chapter provides a taste of some recent developments aimed at improving the utility of this group of shelled marine protozoans.

PALEOPRODUCTIVITY

Unlike the organic matter (OM) record, which essentially registers the amount of refractory organic carbon (C-org) that has bypassed the sediment/water interface, the Benthic Foraminifera Accumulation Rate (BFAR), which is defined as the number of specimens/unit area/unit time, fluctuates in relation to the downward (i.e., exported) flux of labile OM which is consumed in the benthic ecosystem. Where bottom water oxygen concentrations remain above 0.5 ml/l, the BFAR may be useful as an estimator of “export productivity” (Jorissen, 1998). Relatively productive intervals are marked by opportunistic faunae that are able to produce high numbers of offspring per gram of labile OM arriving at the seafloor. For example, phytodetritus flux (= labile OM) has been shown to trigger the rapid opportunistic reproduction of some shallow infaunal taxa (Textularia kattegantensis, Fursenkoina sp.) in Sagami Bay, Japan (Kitazato et al., 1998).

The previous parts of this book use the general and informal term “testate rhizopods” to indicate both foraminifera and thecamoebians. Up to this point, however, the discussion has focused almost exclusively on foraminifera. This is because of the enormous body of information available on these organisms, which have been a key tool of micropaleontologists for either commercial or environmental applications for more than a century. Thecamoebians, on the other hand, have been the exclusive domain of geneticists, biologists, and taxonomists; no attempt has been made to use them as geological proxies until very recently. These organisms are not a familiar subject for most environmental managers. The literature concerning them is mainly in nongeological journals and is not always readily available. Although they inhabit mainly freshwater bodies, thecamoebian tests, either transported or indigenous, are also found in marginal marine environments. For these reasons, it was deemed appropriate for this book to summarize some of the relevant general information on these organisms in somewhat greater detail than was done for foraminifera.

THECAMOEBIANS

General Considerations

“Thecamoebians,” although morphologically similar and taxonomically close to foraminifera, are mainly freshwater organisms; very few forms tolerate mildly brackish conditions. The term “thecamoebians” (= amoebae with a test) is an informal one used to characterize a very diverse “group” of organisms belonging to two different classes within the subphylum Sarcodina (Fig. 1.1).

This book represents a summary of the experience and knowledge amassed by the authors in total of over ninety years of research on foraminifera and thecamoebians. Naturally, it was not possible to include everything that has been written on the subject, and we have drawn heavily on our own work for case studies. It is appropriate here to acknowledge some of the earliest pioneer workers on this subject, particularly Orville Bandy and his former students at the University of Southern California, who were among the first to show how foraminifera could be used as marine pollution indicators. Fred Phleger and his students at the Scripps Institute of Oceanography did pioneering work on modern distributions of coastal foraminifera. One of those students, Jack Bradshaw, introduced David Scott to this field in the early 1970s. At the time when the likes of Bandy and Phleger performed their early work, microfossils were restricted mainly to biostratigraphic applications, and their utility as environmental indicators was almost completely overlooked. We owe them a debt of gratitude for persisting and making this book possible.

This work could never have been completed without the help of countless students, technicians, and colleagues at both Dalhousie University and the Bedford Institute of Oceanography. Anyone who might have participated on surveys or published findings in refereed journals over the past twenty-five years is here collectively thanked.

From the end of World War II through the 1960s solar enthusiasts sought to shape public understanding of solar technology and to influence government policy toward it. During this period solar advocacy began to mature, with the establishment of research programs, professional and advocacy associations, technical journals, popular writings, and conferences. Within this growing group of advocates, consisting mostly of scientists and engineers, a core of experts emerged on whom the government could and did call for advice about solar issues. However, debates within this core about the potential for solar energy made it difficult for advocates to depict it as a technology that government policy makers should take seriously, especially given the framing of the broader energy debate.

SOLAR TECHNOLOGY: STATE OF THE ART AFTER THE WAR

Even before World War II some solar technologies enjoyed experimental or even commercial use. For example, by October 1939, Palmer Putnam, a consulting engineer and a central figure in solar energy circles, persuaded a Vermont electric utility and a turbine manufacturer to test his design for a large wind turbine that would feed electricity directly into the utility's grid. By October 19, 1941, they had finished a large, 1.25-megawatt wind turbine with 175-foot-diameter blades, sited on the top of Grandpa's Knob, a treeless mountain near Rutland, Vermont, and began generating electricity. The machine ran well for two years, until a bearing wore out that took two years to replace due to war-time shortages of such parts.

On June 20, 1979, President Jimmy Carter dedicated the solar hot water heating system newly installed in the West Wing of the White House. A “Who's Who” of solar energy advocates joined him at that ceremony. Although they provided part of the White House's hot water needs, the solar collectors served more importantly as a symbol of Carter's commitment to promoting solar energy to meet the nation's energy needs. This ceremony marked the symbolic height for solar energy within the executive branch. Not only did the president announce new policy initiatives, he did so while publicly associating himself with the activists and government officials who had been pushing for them, and all of this against the backdrop of solar collectors on the White House roof. No activist could ask for a better scene and set of props. The event was not only a symbolic peak but a policy peak as well, for solar had never before been treated by the federal government with such generosity or seriousness.

Yet, as in any theater, scenes and symbols can mislead as well as inform. The White House ceremony conveyed the impression of solar advocates' great success as President Carter announced policies for which they had been fighting for years. Since many of these very same people had pushed successfully for new environmental laws and institutions, one could conclude that a new movement and its leaders had acquired the resources and skills to influence government policy decisively. Yet such a conclusion would be mistaken.

A key question for any government institution is whether and how citizens can influence its policies. The pluralist model of American government suggests that its institutions are highly permeable, that most organized groups, assuming they can mobilize the necessary political resources, can press their views and affect policy. A more complex view analyzes how institutional rules, practices, and structures deeply influence who can have access to the institution and what kinds of access they can have. In executive branch agencies the White House staff could limit solar advocates' access to top decision makers by appointing officials not friendly to those advocates. On the other hand, the discussion in Chapter 5 of the conflict between the White House and both the Energy Research and Development Administration (ERDA) and the Council on Environmental Quality (CEQ) in the Ford administration suggests that the staffs in those agencies, particularly below the political appointee level, often thought about energy problems quite differently than did the White House and may have been a channel of influence for advocates who could not get access to the White House.

In addition to the agencies, the administrations sometimes operated ad hoc policy studies and processes. These activities often got much press and advocates' attention. I analyze one of them at length, the Solar Domestic Policy Review (DPR) of the Carter administration, examining how it provided outsider access to the policy process, to whom it did so, and the effect of such access.