Click for next page ( 106


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 105
4 Complements to Genome Science: Enabling Technologies, Facilities, and Infrastructure Genomic methods (broadly defined) stand to make significant contri- butions to polar biology, but the successful application of these new meth- odologies is likely to depend on a suite of other enabling technologies. Enabling technologies include sophisticated methodologies for integrat- ing biological data with information from geochemical and geophysical analyses, improved means for providing access to field sites during winter conditions, improvements of laboratory and storage facilities, advanced technologies to allow remote sensing of organismal activities, and better methodologies for accessing specimens found in difficult-to-sample habi- tats such as subglacial lakes. ENABLING TECHNOLOGIES Examples of New Approaches to Link Organismal and Process Data New and improved stable isotopic techniques, used alone or in parallel with molecular methods, can help unravel how organisms respond to the uncertainties of global change and how they contribute to the functioning of polar ecosystems. Advances in stable isotope techniques can help scientists understand the links between organisms and geochemistry (e.g., nutrient, carbon, silica, hydrology cycles). Techniques include the following: Multiple element (30Si/28Si, Ge/Si, ION, ]3C, ]80) or coupled analyses (TIC, H2~804. These analyses improve our ability to study organisms as 105

OCR for page 105
106 FRONTIERS IN POLAR BIOLOGY IN THE GENOMIC ERA participants in complex interactions. For example, these analyses can be used to resolve whether plant stomata! or photosynthetic processes are affected by environmental perturbations, or to characterize the BIRO values of precipitation (soil water or snow) or soil and organism BACON under a suite of climate change scenarios, indicating changes in photosynthetic pathways, sources of respired substrates, or other geochemical processes. Compound-specific stable isotope studies. Compound-specific stable isotope measurements improve resolution of bulk carbon characteristics because the multiple sources of carbon (undegraded plant lignin, poly- saccharides, etc.) can be identified (Neff et al., 2002~. When compound- specific stable isotope techniques are combined with traditional bulk stable isotope or radioisotope analyses, the power of biogeochemical research increases substantially due to our enhanced ability to resolve carbon sources, including paleocarbon sources. Increased resolution of mass spectrometers. The high resolution of mass spectrometers now allows minute quantities (<20 fig) of microscopic invertebrate species to be analyzed. The finer resolution increases the potential for integrating the details of food sources, energy, and nutrient transfer in smaller organisms of the microbial food web that were previ- ously neglected or grouped with larger organisms or sediments. Stable isotope techniques and molecular techniques can be used in parallel to discriminate the ecosystem function of a particular group of microorganisms. Techniques include the following: Functional-level analysis. Functional-level analysis combines ~3C tracer studies with specific phospholipid fatty acids (PLFAs). Distinct PLEA profiles are characteristic of such organisms as fungi, Gram-positive bacteria, and actinomycetes. When measurements of PLFAs are com- bined with stable isotopes, a powerful tool is available for following carbon flow through microbial communities. Stable isotope-probing (SIP) techniques. SIP is an advanced culture- independent technique that allows isolation of DNA from microorganisms at a species level. An advantage of the technique is that it allows isolation of entire genomes of, for example, active methylotrophs in ~3C-DNA fractions, which enables a parallel analysis of functional gene sequences within populations. These rapidly developing techniques have enormous potential for understanding diversity and function across spatial and tem- poral scales, as well as for understanding relationships to complex bio- physical properties found in polar regions.

OCR for page 105
COMPLEMENTS TO GENOME SCIENCE Fluorescence-Based Technology 107 Fluorescence-based technology, such as fast-repetition-rate fluorometry (FRF) (Behrehfeld et al., 1996; Kolber et al., 1994), pump during probe (PDP) (Falkowski and Kolber, 1993), and pulse amplitude-modulated (PAM) fluorescence (Renger and Schreiber, 1986; Schreiber et al., 1994), is now commonly used to study photochemical yield of algal photosynthesis. The following are some useful advancements in fluorescence technology that may be of use to polar scientists: Microfluorometer. Measurement of the quantum yield of photo- synthesis for single cells or colonies is now possible by attaching an epi- fluorescence microscope to the PAM fluorometer. Such measurements allow assessment of a single cell or single species' response to different light, nutrient, or temperature regimes and may lead to predictions of taxonomic succession under changing environmental conditions. Submersible PAMfluorometer. A submersible prototype of the PAM fluorometer that has substantially higher sensitivity than the commer- cially available dive PAM is being tested in the Ross Sea (W.O. Smith and I.A. Peloquin, personal communication, October 16, 2002~. The submers- ible prototype can be lowered to approximately 30 m, thereby allowing measurements of the vertical structure of fluorescence characteristics. These instruments can be used to study the effects of such abiotic factors as ultraviolet radiation and temperature on the vertical structure of phyto- plankton. Biosensors, On-board Instrument Packages, Electronic Tagging, and Nanotechnology Obtaining data on free-ranging organisms in the field is challenging in all environments. However, the polar regions pose special challenges, notably those associated with efforts to observe organisms in the field on a year-round basis. Many of the problems created by the harsh environ- ment can be reduced through the development and exploitation of technologies that involve remote sensing, on-board instrument packages, electronic tagging, and newly emerging applications of biosensors and nanotechnology. Instrument packages and tags. Small and versatile instrument packages can be attached, permanently or reversibly, to study animals that are subsequently released back into the field. These instruments allow a variety of measurements to be made, including geoposition, depth, heart rate, and, in some applications,blood chemistry. (See for a review of this technology and a com-

OCR for page 105
108 FRONTIERS IN POLAR BIOLOGY IN THE GENOMIC ERA prehensive bibliography of studies in which this technology has been employed.) Nanotechnology and biosensors. New types of instruments employing sophisticated DNA and protein-based biosensors that exploit the poten- tial of nanotechnology are in development (see Chibber et al., 2002, for an example). Of special promise are instruments able to sense specific types of biochemical signals in the environment. For example, sensors to which specific DNA molecules or antibodies are attached could provide means for characterizing the compositions of aquatic microbial ecosystems or for charting plankton blooms. Subglacial Lake Exploration The discovery of subglacial lakes some 4 km beneath the surface of Antarctic ice sheets offers unparalleled opportunities for research, but also unparalleled challenges. A number of enabling technologies will be required to study the form, distribution, and activity of life in the lakes (SCAR, 2001~. One critical aspect of subglacial lake exploration is testing, verification, and monitoring for potential contamination during all phases of the scientific program. All of the methodologies employed, from ice drilling to sample recovery, must be scrutinized carefully and deliber- ately from both an environmental stewardship and a scientific stand- point. To develop a subglacial lake exploration program and move ahead with ice-based biological research, enhanced field logistics and new tools for sampling and archiving data would be needed. Examples include: Fast-access drilling technology. Subglacial lake exploration will require targeted sampling and observations from multiple boreholes drilled over a wide geographic region. Mobile and rapid drilling is required for such work. One example of fast-access drilling was a hot-water system used until recently to investigate the controls on fast-ice flow in West Antarctica. Unfortunately, this hot-water drill can drill only to a depth of ~1 km, whereas most of the Antarctic ice sheet is considerably thicker (~2-4 km). Clow and Koci (2000) have proposed a system based on coiled tubing technology that illustrates one approach for fast and mobile drilling to all ice sheet depths. Clean drilling and sampling technologies. These technologies form perhaps the largest hurdle in subglacial lake exploration and must con- sider both forward and backward contamination issues. Before sampling can begin, a water lock must be developed that will allow all sampling equipment to be properly decontaminated and to ensure that the lakes remain isolated from the atmosphere. The waterlock system should be

OCR for page 105
COMPLEMENTS TO GENOME SCIENCE 109 integrated with the developing fast access drill technology. Once devel- oped, such technology will open the door for the placement of in situ observatories and sample return missions. In situ observatories. An initial step in subglacial lake exploration should include the deployment of an observatory or series of observatories. These observatories would acquire a time series of such basic measure- ments as dissolved oxygen, conductivity, redox, pressure, temperature, and turbidity using sensor strings located at selected depths throughout the water column. Molecular arrays should be developed to give an initial picture of the microbial types and their metabolic capabilities. High-pressure culture technology. Although it is not known if microbes living in subglacial lakes are adapted to elevated hydrostatic pressures and require these conditions for optimal growth, attempts should be made to determine whether experiments with the subglacial lake biota will be enhanced by high-pressure culture technology, as has been used in studies of deep-sea microbes (Yayanos, 1986~. FACILITIES AND INFRASTRUCTURE Creating a Virtual Sequencing Facility to Coordinate Large-Scale Sequencing Efforts Realizing the full benefits of genomic-based approaches to the study of polar biology will require significant work and sophisticated facilities. A number of facilities capable of supporting sequencing activities for polar biology already exist, along with a large pool of talented scientists, so there is not an immediate need for new facilities. Instead, one of the greatest challenges in the implementation of a genomic research program in polar biology will be to identify the most appropriate mechanisms for accomplishing the work. Different approaches are possible. At one extreme would be a model where individual investigators with interest in a particular organism carry out genome sequencing activities in their own laboratories. At the other extreme would be the model in which large-scale sequencing centers that routinely produce billions of base pairs (bp) of DNA sequence each year would perform the work. There are pros and cons to both models; how- ever, there is an economy of scale in both time and money that comes from having this work carried out in large centers. In the United States alone, the estimated combined DNA sequencing capacity in medium to large centers is approximately 500 million lanes per year more than enough to meet the needs of the polar biology research community in the near future. In addition, the large sequencing centers also have the appropriate bioinformatics tools and pipelines to support genome anno-

OCR for page 105
110 FRONTIERS IN POLAR BIOLOGY IN THE GENOMIC ERA tation and analysis. What the large centers do not have is the expertise to link DNA sequence data to the biology of polar organisms. This means that there is no immediate need to build additional infra- structure to support sequencing activities. Instead, the expertise of scien- tists from diverse backgrounds must somehow be coordinated in some sort of "virtual" sequencing facility. This approach would blend the expertise already within the polar research community with the expertise in genomics and bioinformatics that resides in large-scale sequencing centers. This hybrid model could be implemented in several ways, such as encouraging individual investigators to establish collaborations with scientists from large-scale centers or having funding agencies facilitate these interactions. Given the wide range of organisms that are being considered for genome analysis, it is likely that multiple models of col- laboration will be needed. Design of such a virtual approach to providing sequencing facilities would take careful thought. It would need to ensure that a diverse port- folio of activities, occurring at different locations and involving different teams of researchers, were adequately coordinated. It would need some mechanisms to minimize duplication of effort and identify potential opportunities for cost-sharing among partners. Some lessons could be learned from experiences gained with the University-National Oceano- graphic Laboratory Systems (UNOLS), which has shown how academic institutions and national laboratories can join forces and facilitate coordi- nation among researchers with a common equipment need (e.g., ships). There are also lessons to be learned from the Ocean Drilling Program (ODP) (now the Integrated Ocean Drilling Program or IODP) experience, a long-term international research program that links universities, indus- try, and government. As described in Chapter 3, coordination in the selection of organisms for sequence analysis will be critical. This is particularly important for microorganisms, given that sequencing is being carried out in a variety of ways, in laboratories around the world, and with funding from a number of federal and private agencies. In the United States, an Interagency Working Group on Microbial Genomics has been established by the National Science and Technology Council to provide a forum for discussion among interested parties about priorities and objectives and to build a more efficient coalition in a coordinated manner. Although prioritization of organisms for sequencing is difficult, the criteria outlined in Chapter 3 provide an initial framework and a starting point for further discussion. As costs for DNA sequencing continue to decrease, the number of pos- sible species that can be selected for sequence analysis will continue to grow. The polar research community needs to provide input into the selection discussion through specific workshops to discuss these ques-

OCR for page 105
COMPLEMENTS TO GENOME SCIENCE 111 lions and through individual investigator-initiated proposals. At this point in the development of genomics, any additional genome sequencing projects related to polar organisms will add considerably to the existing body of knowledge. Sample Repositories and Culturing Facilities Establishment of a base-funded and staffed repository for frozen samples of polar organisms would serve functions that are becoming increasingly important as new genomic and postgenomic technologies are being trained on problems of polar biology. Such a facility would: provide long-term maintenance and curation of frozen samples, thereby allowing genetic comparisons with natural populations in the future; offer new investigators in polar biology the opportunity to obtain samples to conduct pilot studies that could ultimately form the basis for a more complete proposal without the need for actual deployment to field sites; and provide access to samples of polar organisms to the broader com- munity of biologists. The most probable site for such a facility would be associated with a university or other research institution. Sample storage would most prob- ably be in a "freezer farm" of ultracold freezers, each equipped with a liquid-nitrogen cryogenic backup system. At least one full-time staff person (initially) would be needed to oversee curation and maintenance. Operation of such a facility would require: developing a system of labeling and inventory control for manage- ment and retrieval of samples and archiving and curation of samples submitted to the repository. Ancillary requirements of infrastructure would include: establishment of a means of ensuring the quality and identity of samples submitted for deposition (e.g., how do we know that it is really from the species purported by the submitter? How can we be sure that the sample has been handled in a satisfactory fashion prior to deposition?; establishment of an oversight committee or manager to evaluate the scientific legitimacy of requests for samples; and development of a set of clear conditions and expectations for use of samples that the requesting investigator would have to accept before samples would be released from the repository.

OCR for page 105
2 FRONTIERS IN POLAR BIOLOGY IN THE GENOMIC ERA After establishing such a facility, individual polar investigators could respond to other scientists' requests that samples be collected for them by directing them to the facility, with explanation that a codified process has been established for such a request. Arctic Biology Laboratories Arctic marine and terrestrial biological research conducted by U.S. scientists is currently limited by the small number of U.S.-supported research facilities and their lack of sophisticated instrumentation (see Plate 7~. This problem is ameliorated to some extent by international agreements that permit access by U.S. scientists to the excellent facilities maintained by Canada, the Fennoscandian countries (Denmark, Finland, Norway, and Sweden), and Greenland. Access to the research facilities of Russia is, at present, problematic. The two major U.S. research facilities are located in the Arctic at Barrow (71.3N, 156.78W) on the Arctic coast of Alaska and Toolik Field Station (68.6N, 149.6W) in the foothills of the Brooks Range on the shore of Toolik Lake. The Barrow facility began as a Navy laboratory and is now owned and operated by the Ukpeagvik Inupiat Corporation (The Barrow Village Corporation). The Barrow Arctic Science Consortium provides logistics support for research projects. The facility provides access to marine, sea-ice, coastal, inland tundra, and freshwater eco- systems. Lodging is limited, and laboratory equipment is spartan (), but year-round science support is avail- able. Toolik Field Station, established in 1975 and managed by the Uni- versity of Alaska's Institute of Arctic Biology, supports research in lake, riparian, taiga, tundra, and wetland environments. The station can sup- port 40 researchers under normal circumstances and up to 80 for short periods. Laboratory equipment on-site is modest, and there is limited support for molecular and genomic research. Currently, only a handful of researchers conduct genomic research in the Arctic, and this may be a reflection of the absence of high-technology facilities. In the near term, the creation of a molecular biology laboratory will facilitate the application of new biological tools in Arctic bioscience. This laboratory should include capabilities such as real-time PCR (TaqMan) and a microarray reader for monitoring the regulation of gene transcription. (Production of gene chips and sequencing are best done elsewhere as described in Chapter 3.) These technologies would be useful to investigators irregardless of the length of their field seasons. For those with long periods on-site, seasonal processes could be monitored and data collected and analyzed in real time. Short-term investigations of particular events would also benefit because P.I.s could verify that the

OCR for page 105
COMPLEMENTS TO GENOME SCIENCE 113 phenomenon of interest is occurring before commencing intensive sam- pling; currently, such sampling must be conducted blindly. Similar argu- ments support the provisioning of Arctic facilities with two-dimensional gel electrophoresis equipment for proteomic work. NSF is to be com- mended for its efforts to upgrade these facilities, including buildings, laboratory equipment, and science support personnel. Polar biologists from the U.S. should be urged to access research sites in the Canadian high Arctic that provide unique habitats (e.g., the peren- nial salt springs on Axel Heiberg Island and other sites that are analogous to the permanently ice-covered lakes, glacial ice, and subglacial soils of the Antarctic). The Canadian Polar Continental Shelf Project (PCSP) coor- dinates support for Canadian government and university scientists and non-Canadian researchers working in isolated areas throughout the Ca- nadian Arctic (~. Non- Canadian researchers are required to have secured funding prior to apply- ing for logistical support by PCSP. PCSP support includes transportation, communication, accommodation, field equipment, and related services. PCSP research facilities do not have any laboratory instrumentation or high-technology equipment, so the conduct of genomic research there may be very limited. U.S. biological research in the eastern Arctic has traditionally been supported through an international agreement with Denmark. Major facilities available to U.S. biologists include the Danish stations Kangerlussuaq (southwest coast of Greenland, 67.0N, 50.7W ~ and Zackenberg (northeast coast; 7430' N. 2030' W) and the U.S. air base at Thule (northwest coast; 76.5N, 68.8W). Ecosystems available at these locations include coastal, marine, riparian, sea ice, tundra, and wetland. Given its extreme northern location and relative ease of access via weekly Air Mobility Command flights, lO9th Air Wing flights, and commercial flights from Copenhagen and Kangerlussuaq, Thule can potentially be developed as another major marine-terrestrial research station. Svalbard (also known as Spitsbergen) offers a unique opportunity for the development of an international polar marine-terrestrial biology station. The island, ~79N, is located near the average permanent extent of northern sea ice and is home to the Ny-Alesund Large-Scale Facility for Arctic Environmental Research. The Atmospheric Climate Research and Biological Research Facilities of the Norwegian Polar Institute support research on physical parameters that affect climate, on ultraviolet (UV) radiation and its biological effects on marine and terrestrial ecosystems and on the marine ecology of Arctic glacial fjords. Ny-Alesund is open primarily to researchers from the European Community. NSF is negotiat- ing an agreement to open the facility to U.S. polar scientists, and this access could have significant payoffs for polar scientists in general and

OCR for page 105
4 FRONTIERS IN POLAR BIOLOGY IN THE GENOMIC ERA biologists in particular. Access to the climate research center will allow complementary studies on the effects of global climate change and UV radiation across the Arctic and in the Antarctic. Furthermore, compara- tive genome analyses of organisms in both poles can elucidate polar organisms' strategies for acclimation to the changing environment. Year-round Access to Polar Facilities Winter at high latitudes poses exposure to one of the most extreme low-temperature, aphotic environments on Earth. Polar ecosystems are end-members of significant global importance. They represent a natural laboratory in which unique adaptations can be elucidated, and their ori- gin and evolution understood, because most polar organisms are not just "surviving the extremes" but are actively feeding, growing, and repro- ducing. Study of polar ecosystems in winter will yield new information that can be used to identify and begin to understand the physiological processes and evolutionary pathways that lead to adaptation to life under extreme conditions. Most scientific activities at high latitudes are currently limited to the sunlit spring, summer, and autumn periods. Access to Arctic and Antarctic terrestrial field sites is severely limited by logistics and safety concerns in the winter. In the marine environment, access by traditional surface vessels to polar waters is limited due to the presence of pack ice, especially in winter, and is hazardous because the waters are often poorly charted and can contain icebergs. Although seasonal constraints on scientific research may not be a significant impediment for some studies, for others the lack of access and physical presence means that datasets are incomplete. All liquid water systems (for example, in and beneath sea ice, lakes and brine ponds, subglacial lakes) in polar regions support life. The life-supporting behavioral and biogeochemical processes occur year-round; these pro- cesses do not cease during winter darkness. Consequently, knowledge and understanding of the seasonal variability of physical and biological processes and interactions in these systems are severely limited by a lack of winter data collection, direct observation, and experimentation. Annual datasets are necessary for the following reasons: Meteorological conditions control biogeochemical rates and fluxes. Without coverage of the annual cycle, physical, chemical, and bio- logical balances cannot be constructed for temporal comparisons with other global systems. Overwintering strategies of all life forms are crucial for under- standing the persistence and evolution of organisms in these climates.

OCR for page 105
COMPLEMENTS TO GENOME SCIENCE 115 Their life history strategies cannot be deduced from studies in other habi- tats and ecosystems or from the summer season only. Processes that occur during winter (at any latitude) are inextrica- bly linked to summer processes and vice versa. NSF's Long-Term Eco- logical Research (LTER) initiative realized the significance of obtaining data on annual scales and stressed the importance of annual material balances for cross-site comparisons and for assessing long-term data trends. Annual datasets allow an assessment of immediate ecosystem response to global change and provide information to understand how biodiversity and biocomplexity are related to global changes. Some ideas and potential solutions that address constraints on winter access to polar regions are as follows: Initiate transition from "daylight-only" to year-round access for field stations such as Toolik Lake and McMurdo. Longer access will also allow greater flexibility for a broad range of scientists to participate directly in field research and will encourage new participants to enter polar research. This new thinking should, in turn, produce new insights on polar ecosystems, enhanced scientific interaction, and synergy of ideas. Request access to a declassified nuclear submarine with no or mini- mal military missions. The Science Ice Expeditions (SCICEX) program organized jointly by the Office of Naval Research and NSF demonstrated that nuclear submarines are effective sampling platforms for frozen oceans and not just for marine geology and geophysics or physical oceanographic measurements (Langseth et al., 1993~. The SCICEX program generated unprecedented data on the biogeography of Arctic microbial populations (Bang and Hollibaugh, 2000, 2002; Ferrari and Hollibaugh, 1999) and also hosted studies of macrobiota such as amphipods. Although this program has ended, such programs could benefit polar genomics-enabled research by enabling survey work unimpeded by ice and access to winter popula- tions of marine organisms. Further, this platform is conducive for the deployment of autonomous samplers. Establish floating observatories such as the one used in the joint U.S.-Canada Surface Heat Budget of the Arctic Ocean (SHEBA) program (Levi, 1998) and the one used in the international program led by Canada known as Canadian Arctic Shelf Exchange Study (CASES) currently planned for 2003-2004. The SHEBA program was modeled after the ice camps that have been used in Arctic exploration for more than a century but featured a floating marine station in the form of a Canadian ice- breaker that was allowed to freeze into the ice. The camp drifted with the ice pack for one year and 800 km, providing opportunities for sampling a

OCR for page 105
116 FRONTIERS IN POLAR BIOLOGY IN THE GENOMIC ERA host of biological and physical variables. The SHEBA program and its predecessors such as the Trans Arctic cruise of 1994 (Wheeler, 1997, and other papers in that volume) also demonstrate the crucial role that inter- national collaborations can play in U.S. polar research. Neither of these programs would have been possible without collaboration with Canadian scientists. Continued development of autonomously and remotely operated vehicles (AOVs and ROVs) and moorings may provide mechanisms for obtaining samples relevant to genomics-enabled research. Possible appli- cations, besides sample collection, may be the in situ detection of specific organisms that would permit time series analysis of population dynamics or studies of vertical or horizontal distributions that are currently con- strained by ice cover. Coastal Research Vessels Polar marine biology is ultimately dependent on the availability of a fleet of vessels with complementary mission capabilities. In the Arctic, the U.S. Coast Guard Cutter Healy (WAGB 20, 420 ft.) and the UNOLS R/V Alpha Helix (133 ft.) provide research platforms of large and intermediate- small size for multiseason research at high northern latitudes. In the near future, the Alpha Helix will be replaced by the larger, as yet unnamed, Arctic Region Research Vessel (226 ft. overall). Other large and interme- diate vessels of the UNOLS fleet frequently work in boreal polar waters (and occasionally in the Southern Ocean). Near-shore research is sup- ported by smaller vessels such as the R/V Montague (58 ft.) of the Alaska Department of Fish and Game and the R/V Tiglax (~120 ft.) of the U.S. Fish and Wildlife Service. Beyond these U.S. resources, the vessels of other nations that border the Arctic are sometimes available on an ad hoc basis. Development of jointly funded projects can enable unique, highly productive expeditions, such as the U.S.-Canada SHEBA program (Levi, 1998) and the International North Water Polyna Study (Deming et al., 2002~. International cooperation with Canada and other nations enhances access to the North American Arctic coastline and the central Arctic basin. The history of the U.S. Antarctic research vessel fleet is one of growth in size and capability, yet of limitation in number. Various U.S. Coast Guard icebreakers (for example, the Wind class, the Glacier, the Polar class) have provided some research support, but their major function has been to open the channel to McMurdo Station in support of the annual logistics resupply. Mission-oriented research vessels have included the R/V Hero (a 130-ft., motor-sailor that primarily served Palmer Station from 1968 to 1985~; the R/V Polar Duke (a 219-ft. ice-strengthened research and supply

OCR for page 105
COMPLEMENTS TO GENOME SCIENCE 117 vessel with substantial oceanographic capability, in service 1985-1997, largely in the Antarctic Peninsula-Palmer Station region); the R/V Nathaniel B. Palmer (a 308-ft. ice-breaking, multidisciplinary research vessel that entered service in 1992~; and the ARSV Laurence M. Gould (230-ft., the Polar Duke's replacement, in service 1997 to the present). The design and construction of the L.M. Gould has provided a further significant advance in the sophistication of shipboard science. Demand for use of the Gould in support of deep water and more distant offshore science has been increasing steadily since her deployment, inevitably lead- ing to heightened competition with demands from near-shore science based at Palmer Station. Furthermore, near-shore work is constrained by the Gould's size and draft. To enhance science opportunities in the Antarctic Peninsula while permitting the Gould to be exploited more effectively as an oceanographic research platform, acquisition or charter of a third, smaller research vessel is under discussion. U.S. National Ice Coring Laboratory The U.S. National Ice Core Laboratory (NICL) is a facility for storing, curating, and studying ice cores recovered from the polar regions of the world. It provides scientists with the capability to conduct examinations and measurements of ice cores, and it preserves the integrity of these ice cores in a long-term repository for current and future investigations (~. With the discovery of numerous subglacial lakes in Antarctica and related discoveries on the biodiversity, evolution, and physiology of the organisms present in deep ice cores, enhancing and expanding the current facility will be necessary to accom- modate additional deep ice core samples for biological analysis. Rationalizing and Improving Specimen Transport Given the great importance and high logistical costs of obtaining sci- entific samples in polar regions, it is imperative that samples are handled and returned to home institutions carefully. Samples are returned from Antarctica to the United States either by vessel shipment to California followed by surface or domestic airfreight to home institutions or via military and commercial air shipment directly from Antarctica either as hand-carried or checked baggage. This system generally works well, but on occasion valuable samples have warmed unacceptably during transit. Figure 4-1 presents data from a temperature logger placed with samples during vessel shipment from McMurdo Station to Point Hueneme, Cali- fornia, showing that samples warmed from near -20C to 0C and cooled

OCR for page 105
118 FRONTIERS IN POLAR BIOLOGY IN THE GENOMIC ERA _ ~ _ _ ~ ~'' ~ ~ ~ . .. , .. _ _ . FIGURE 4-1 Sample temperature recorded during shipment of samples from McMurdo Station to Point Heuneme, California. Note that the samples reached 0C for a 12-day period during shipment; the requested shipping temperature was -20C. SOURCE: l.C. Priscu. back to -20C over a 12-day period. Such warming can compromise many types of samples. Without the temperature record made during shipment, scientists could misinterpret data subsequently obtained from compromised samples. Care must be taken to maintain desired tempera- tures during shipment, and all investigators should be presented with detailed temperature records during the period of shipment.