GEOMORPHOLOGY R.A. Marston Book Chapter 1989 in Geography

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R.A. Marston

1989 Book Chapter WWRC - 89 - 27

Geography In America

R.A. Marston Department of Geography and Recreation Wyoming Water Research Center University of Wyoming Laramie, Wyoming GEOGRAPHY IN AMERICA

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MERRILL PUBLISHING COMPANY A Bell & Howd Information Company Columbus Toronto London Melbourne 71 environments of the Quaternary are included, reflecting the nand ties of these fields ~mo@olw to gmmorphology. American geographers in geomorphology are defined as those who practice their profession in the United States, a definition that includes approxi- mateiy 5% of the topl AhG membership and 21% of all practicing geomorpho1ogh.s in he United States.’ Separating the contributions of American geographers from the contributions of gamorphologists having backgrounds other than geography, and from geographers who practice geomorphoiogyoutside the U.S., is a task that has not been pursued in he literature. This is a separation that is somewhat artificial in light of the increasing interaction between geography and other disciplines, and the increasing oppomnities for exchange of information between colleagues in countries worldwide. Indeed, Vi- Geomorphology [ek (1988) argued that institutions (professional societies, universities, and inford pups) and the transfer of enthusiasm and ideas by influential practitioners have Richard A Marston become more importanc factors in the advance of the discipline than one’s particular field of training. A significant portion of the research by American geographers in geomorphology is concerned with topics that are not geographical in the sense of integration, synthesis, and predictive spatial modeling. Nevertheless, it is critical to solidifying the posi- eomorphology is the science that studies landforms and soils in a historical and tion of geomorphology within geography to identify a sample of those works that pursue the integration-synthesis-predictionthemes, among other important contribu- G functional context, including morphological elements, physid and chemical processes, and merials of composition. If training in geography provides a special tiOnS. A number of manuscripts have been published recently that address various opportunity for making contributions to geomorphology, it is in studies that examine as- interactions between geomorphic and related biophysical systems, human interfer- pects of the field: the satus of geomorphology (Pircy 1982,1985;Hart 1986; Bashenina ence in geomorphic systems, and predictive spatial (dynamic and statistical) modeling et al. 1987; Cooke 1987; Trim 1987); the function of geomorphology within physical geography (Gregory 1985); and the position geomorphology other subfields) of morphological, cascading, and process-responsesystem in geomorphology.These of (and in Uohnston 1985). Baker (1986) and Ritter (1988) provide the opportunities closely parallel the “integration,” “synthesis,”and “prediction,”respec- geography perspective of American geologists on the nature of geomorphology. Walker md Orme (1986) tively, described by Orme (1985) as the preferred goals of the geographer’s science. offer some clues to the nature of geomorphology at an international level in the chapter describes the impact of American geographers on the discipline of as This 198% based on themes evident in the First International Conference on Geomor- geomorphology. is accomplished through: This phology. These reviews all paint an optimistic future for the discipline of geomor- 0 inventory of research in geomorphology published by American geographers; phology, but the influence of American geographers is not apparent. 0 citation of selected works by American geographers in areas of geomorphology The themes, developments, potentials, and needs of geomorphology in geogra- where a geographer’s perspective has proved useful in the development of phy were stated at he bqnning of the decade by Gnf and his colleagues, although fundamental concepts; and the contributions by American geographers were not singled out. Graf et al. (1980) 0 discussion of the participation by geographers in professional geomorpholog- applauded the new pluralism in geomorphology and pointed out the following major idorganmtions. developments, all of which remain valid late in the decade:

This is not intended as a historical review of geographical geomorphology,but rather . . . an increased dependence on field research (an old tradition revisited), more re3listic a report on the current aims, methods, and central ideas, as well as possible future ~~tionsfrom rmch tools, a resurgence of interest in man-land relationships with a directions that geographers may pursue. Trends in the studies of soils and physical ~ncomimntdependence on the historical approach, an expanded appreciation of the hy- drologic cycle, a reinvestigation of morphogenetic regions. new interest in planetq sur- ~~ ~~ ‘Ofthe 1435 members in the Quatemarv Geology and Geomorphotogy Division of the G.% (October 1987 faces other than the eych‘s, more detailed investigations of event maptude and frequency, h).approximately 8% are foreign-bh and 4% are geographers. according to the current chau of the and an involvement with applied problems. Division. Of the 268 members in the Geomorphology Speclaicy Group of the AAG (Mav 1987 dara), 3.4% are foreign-based, and 4.9% are geologists. Students comprise approximately 20% of the membership of both In another key ra5ew of the discipline, Graf (1984) reponed on the uneven grwps. Another 63 American geographers claim geomorphology as a s@ty in the Cud ro Lkpm’mm of m&Twin fbe United Stars and cm?adq 198748. Therefore, geologw;tr, number 976 (79.4%)and dbuibution of field loulities for major research effom in American geomorphology geographers number 253 (20.6%)of the toml number of 1229 geomorphologists pncticing in the US. When since 1817. He warned of the dangers of applying geomorphic theories developed foreign-based members of each group are included, geologists and geographers comprise 80.6%and 19.4%, frcm research in one region to investigations in another region without recognition respectiwly, of the toral number of geomorphologists belonging 10 either the GSA or AAG. 70 72 73 m0-u of and adjustment for this spatial bias, particularly with respect to mountain regions pher continued to publish a disproportionately low number of geomorphology pa- ~mo~holo~ PROCESSES AND and fluvial systems. RESOURCES Costa and Graf (1984) e-xamined the numbers, professional affiliations, publia- pers, while the Annals published a disproportionately high number when compared to the percentage of MG members who specialize in geomorphology. Geographers tions and locations of geomorphologists and Quaternary geologists in the United (merican and foreign-based) accounted for 51.2% of the geomorphology publica- States, a review that provided the first statement of the relative contribution of geog- sampled, a figure that is magnified when compared to their percentage of the raphers to geomorphology. tions PncTicing geomorphologists. American geographers contribute relatively few articles 10 the international journals, relying more heavily on those published in the U.S. PUBLICATIONS The topical areas of research by American geographers in geomorphology were investigated by e-xxnining Geographical Abstracts (formerlv Geo Abstracts), Part A An update of the work by Costa and Graf (1984) reveals the number of geomorphol- Land/omtS and the QW-, Part B: Cfimologv and hydro log^ (Hydrology sec- ogy papers published in the period 1976-86, in refereed journals, printed in English, tions only), and Part E: Sedimentology. This bibliographic service provides a compi- with international circulation, and containing at least one geomorphology paper per lation of abstram from formal publications having international coverage. Abstracts year (Table 1). The journals are ranked according to the “impact factor’’ calculated by are classified by major subtopics in geomorphology. the Science Citarion Index and SodScience Citation Imkx for 1986. Note that the The names of 262 American geographers in geomorphology were checked for data do not distinguish between American and foreign-based geomorphologists. entries in Pam -4, B, and E of Geographical AbsfracLs for the years 1980-87. Of the The journals most heavily used by geographical geomorphologm are not among 262 names, only 147 were referenced at least once in the eight years. Many of the those with the highest impact factors, which limits the visibility of research. Un- others are recent Ph.D.s in geography, or among those that list geomorphology as a changed from the earlier survey by Costa and Graf (1984), the Pmfkssioml Geogra- specialty but are not members of the twG Geomorphology Specialty Group. A total of 22,139 abstracts were compiled in Geographical Abstracts, Part A over this time Table 1 penod, and Amencan geographers account for 322 entries (1.45%).An additional 347 PuMshed geomorphology papers, 197646 abstracts by American geographers in geomorphology were cited in the hydrology ~____~~ and sedimentology pam. Twenty-two researchers account for 50% of the papers pub- BY BY All lished by American geographers. Journal Fact08 Geographer Geologist Others Sub-total Papas % Geomorphology The classificauon of entries provides an indication of where American geogra- Geology 2.182 17 73 18 108 1499 7.2 phers are making contributions to the field, in the sense of quantity of pubiished GSA Bulletin 2.163 51 150 26 227 1591 14.3 research (Figure 1). Quaternary studies that emphasize physical environments, slope American J. Science 1.859 9 5 5 19 485 3.9 studies, and fluvial studies account for the greatest concenmion of efforri Receiving Journal of Geology 1.827 16 29 9 54 545 9.9 slightly less emphasis have been publications on periglacid form and process: runoff Qu;iternary-ch 1.750 8 28 16 52 457 11.4 and hydraulics; beaches, barrier islands, and other coasts; glacial landforms and sedi- ~UI~SAAG 1.397 29 6 1 36 341 10.6 ments; weathering and related pedogenesis; soils: and regional physiography. Water Resour. Resexch 1.389 32 19 75 126 1826 6.9 Topics most closely associated with sedimentology have received some attention Gas.Annaler (A) 1.OOO 165 19 33 217 236 91.9 by American geographers. The published research in kxshas been dominated by a Arctic & Alpine Resear. 0.987 55 25 33 113 397 28.5 Earth Sur€ Form & few researchers, notably M.J. Day (e.g., 1983, 1985). A reiauveky small effort has been forthcoming in research involving neotectonics and suuctud control, deltas, am- Pro. 0.817 215 53 96 364 387 94.1 Zeit Geomorphologie 0.730 165 66 75 306 341 89.7 aries, tidal flats, glaciology, and geomorphological mapping. The low number of en- Prof. Geographer 0.678 13 0 0 13 399 3.2 Mes for applied geomorphology is an artifact of the classification scheme used by the Prog. in Phys. Geogr.b 0.661 130 7 21 158 275 57.5 editors of Geographical AbstraaS. Journal of Hydrology 0.586 44 6 35 85 1461 5.8 Re~earchby American geographers on volcanic form and process has been rather Env. Geol& Water Sci. 0.432 4 23 26 53 209 25.4 sparse, in spite of the opportunities afforded by the 1980 eruption of Mount St. He- Catena 0.193 79 7 22 108 222 48.6 len~.Rosenfeld (1980) and Rosenfeld and Cooke (1982) outlined the preeruption se- Physical Geographf 0.097 38 12 0 50 120 41.6 quence of events, the events of 18 (directional blast, landslides and debris TOTALS may flows, (Mean = 1.103) 1070 528 491 2089 10,791 19.4 PyrOChtic activitv, formation of the lava dome), and posteruption landscape devel- SOtrner Data for 1976-80 pericd from Gxa and Graf (1984). opment, Yamaguichi (1984) used tree coring to date previous eruptions of Mount St ‘Impact factor = number of cirations from journal in 1984-85 divided by toml number of citable items in Hehs at AD. 1800 and AD. 1480 that produced distinct tephn layers. Mount St. Hel- that journal in 1984-85, firom the Science Citation ?& and sodal science Cirarion Index for 1986. eflS was the site of the 1986 Conference of the American Geomorphological Field bstarted publication in 1977. Group, generating a renewed interest in the recovery of landscapes disturbed by ’snrced publication ca- in 1980. muophism. 7C II

0 10 20304050 A most-welcome addition to the literature on perighcid environments is the re- ~morpholow QUATERNARY cent book edited by Giardino, Shroder, and Vitek (1987), Rock Glaciers. It is the most General & Doting comprehensive work to date on the topic, with chapters by American geographers on Oceans a review of the knowledge base (Vitek and Giardino 1987b), rock glaciers as pm of Tropics & Subtroprcs the alpine sediment cascade (Olyphant 1987), stratigraphy (Morris 1987), site charac- Mid- Latitude 8 Extraglacral Sea Level & River Terraces teristics and rock-glacier morphometry (Parson 1987), techniques of analysis (Shroder SLOPES and Giardino 19871, movement dynamics (Shroder 1987), and geologcal engineering aspects of rock glaciers (Giardino and Vick 1987). The book contains an extensive FLUVIAL also bibliography (Vitek and Giardino 1987a) that adds to its value a guide to future RUNOFF 8 HYDRAULICS as 37 research on what may be the largest landform of unconsolidated debris in alpine BEACHES, BARRIER IS. a OTHER COASTS -36 environment. PERIGLACIAL - GENERAL GLACIAL LANDFORMS 0 SEDIMENTS IMPORTANT CONTRIBUTIONS BY AMERICAN WEATHERING 8 RELATED PEDOGENESIS GEOGRAPHERS IN GEOMORPHOLOGY SOILS Soil Mechanics It is possible to idenufy several areas where American geographers have had a signrf- Soil Erosion icant impact on current thinking in geomorphology. These areas include the refine- Survey 8 Classification ment and verificarion of geomorphic paradigms;the link among measurement, theory, Systematics Techniques and application in geomorphology (borrowing the theme of an IGU commission); Regional separating the natural variation in geomorphic systems from the fluctuations triggered Microrelief by human activities: and landscape ecology. It is also important to give credit to Amer- REGIONAL PHYSIOGRAPHY ican geographers who have made important contributions to the development of tech- SEDIMENTARY MECHANICS niques in geomorphology, regional geomorphology, and advances in Quaternaq stud- CLIMATIC FLUCTUATIONS ies. These areas are addressed below. PRESENT- DAY OCEAN BASINS APPLIED SEDIMENTATION 8 POLLUTION Refinement and Verification of Paradigms in Geomorphology ANCl ENT SI LICO- CLASTIC SEDIMENTS Four paradigms affect the way in which geomorphologists in North America view BULK PROPERTIES OF SEDIMENTS landscapes (after Schumm 1977): KARST 1. LJniformip4e laws of ph>sics and chemistry control the operation of geo- WATER RESOURCES EI LAND USE EFFECTS morphic processes today as they always have in the past. FLUVIAL ENVIRONMENTS 2. Landform Erolution-landforms result from the interplay of the resisting NEOTECTONICS 0 STRUCTURAL CONTROL framework, dnving forces, and time. DELTAS, ESTUARIES, TIDAL FLATS 3. Cornplant)..-the interpretation of present-day landforms is complicated by GLACIOLOGY changes in the resisting framework and driving forces over time, causing sim- APPLIED GEOMORPHOWGY ilar landforms to develop from different initial conditions, and landforms to a in in VOLCANIC LANDFORMS respond to change the resisting framework and/or driving forces op posite ways at different times. GEOMORPHOLOGICAL MAPPING 4. ThreshoMs--abruptchanges may occur during landscape development,as geomorphic thresholds are exceeded; thresholds are dues involving processes OTHER S E D IMEN TAT1 ON 143 and/or forms that, when exceeded, initiate an episode of accelerated landscape OTHER HYDROLOGY change. Figure 1 The paradigm of uniformity was developed in other branches of physical geology. Number of abstmts authored by American geographers from 1980-87 in 6bgr@biazLA&&, Part It was extended to geornorphology by Suahler (1952, 1980), who is widely acknowl- k I!u?~@~I.s and tbe Qtuibvwry, Part B: CIimtorogV and Hydmhgy, and Part E: Sadimenlology edged as the father of modern quantitative geomorphology for his works on the dy-

74 I 76 77 -0-u namic basis of geomorphology and the logical extenslon of systems theory to the field. river Ied to long-standing problems of border demarcation. Toy and Hadley (1987) &.omorphology PROCESSES AM) Dury (1980) underlined the need for camtrophism as part of uniformity. demonstrated the Iinkages among geomorphic principles, environmental impacts RESOURCES With regard to landform wolution, great advances in understanding the sediment mused by human activities, and the effectiveness of reclamation practices. cascade for various geomorphic systems have followed from particularly innovative or General reviews of opportunities in applied physical geographv and applied geo- rigorous research strategies. Notable work has been done by Trimble (1981) and morphology were presented by Marcus (1979b) and Costa and Fleisher (1984), re- Trimble and Lund (1982) in humid-region fluvial systems; by Graf (1987b) in a dry- spectively. land river system; by Caine (1984) in alpine sectors in the Colorado Rocky Mountains; Coastal geomorphologistshave added to the success in linking measurement, the- by Weirich (1985, 1986b) in high-energy glacial lakes; and by Nordstrom, McCluskey, ory, and application. Terich and colleagues (Komar, Lizarrage-Arciniega, and Terich and Rosen (1986), Allen (1988J and Sherman (1988) in sandv beach environments 1976) used measurements of beach accretion and erosion in a computer simulation These studies serve to illustrate several points. First, improved instrumentation must model to demonstrate that jetties can cause considerable shoreline change, even in remain a priority among geomorphologists as part of the greater need to improve areas of zero net littoral transport. Their findings have been used to guide develop- empirical coefficients and to test theories of sediment transport Second, systematic ment along sandy beaches of the Oregon coast. data collection over a longer time period will yield more-meaningfulresults in geomorphic system, where feedbacks and response times play an important role. Third, separating Natural and Human-Triggered repeat photography and historid records of reservoir sedimentation offer attractive Variation Geomorphic Systems tools for drainage basin scale studies of the sediment cascade. in The complex response in geomorphology was e.xpertly illustrated by Cooke -and The most difficult problem facing geomorphologists may be sepanting the natural Reeves (1976), who proposed a model for arroyo development in the American variation in geomorphic syitems from fluctuations triggered by human acuvities. The Southwest. They demonsuated that arroyos in coastal California and southern Arizona techniques that are used to make the distinction must be sufficientlyrefined to detect are similar in form, but were generated by contrasting scenarios of environmental change over multiple spatial and temporal scales. Graf (1979) combined photogram- change. Complexity becomes the paramount consideration in Quaternary studies, ;15 metric measurements from historical photographs with field measurements to judge described below. the impact of gold and silver mining on mounrain stream systems in Colorado. The thresholds concept was developed in the 1970s, and was quickly used to Threshoid values of erosive force were surpassed in response to changes in general support episodic models of hdscape development (e.g., dynamic metastable equilib- basin vegetation cover, valley-floor vegetation, channel slope, width, and roughness, rium). But recent work by American geographers has complicated this link Coates all subject to human impan and Vitek (1980a) presented an excellent summary of the development of the thresh- A study by Marston and Lloyd (1985) utilized the water-budget approach to ex- olds concept, with examples to illustrate the various types, and their social relevance. plain changes in water supply, and to isolate the effects of channel modificationsalong Salisbury (1980) found that thresholds must be used to explain why the merging of the Rio Grande below El Paso,Tcm. two streams does not always produce a predictable change in vallev form. The effect of silvi~~ltunlactivities on c-el equilibrium and sediment storage However, reliance on thresholds to explain episodic landscape change has been in forest streams an be assessed using the methods described by ,Marston (1982). tempered by Howard (1982), Graf (1983), and Rhoads (1988). They pointed out that Stemberg (1987) attempted to separate the influence of deforestation on flooding and significant landscape change can occur without transgressing thresholds, as disequilib- channel changes in the Amazon River from the influence of rainfall variations and rium is translated spatially throughout the fluvial system. Moreover, Costa and Cleaves neotectonics. (1984) showed that equilibrium and episodic landforms an be found in the same The diEerencial effectof military maneuvers on aeolian transport was the subject modem landscape. Of a paper by Marston (1986b). Waker and Mossa (1986) used 10 case studies along the shoreline of Japan to contrast the influence of human modifications with that of teCtOnic processes, tsunamis, and storm surges. The Link Among Measurement, Theory, and Application overall, however, the humanenvironment (synthesis) theme is not as common Fluvial geomorphology continues to be the focus of much effort by American geog- in the published work of American geographers in geomorphology as one might ex- raphers. It is a subfield where American geographers have attained a high degree of pett, given the training of geographers. A survey of consulting activity would probably success in achieving the synthesis, integration, and prediction aspects of the science. the true extent of this type of work For example, the AAG Resource Publication by Gnf (198%) linked measurement and theory regarding biogeochemical processes in the Colorado River Basin with applica- Landscape Ecology and Earth-System Science tion to river-basin management issues. The book by Mueller (1975) explored problems in political geography along the The application of concepts and techniques from geomorphology to ecosystem stud- US.-Mexico border caused by geomorphic instability of the Rio Grande. He demon- ies and terrain and>sis represents a great opportunity for the discipline, given the strated that misunderstanding of the processes of channel change in an arid-region anent need for an interdisciplinary approach to complex environmental problems. 78 ~ONMFJJTALSeveral emples are available of such research, conducted by American geographers Table 2 mmorphic techniques used geopphers PRocEsSEs AM) in geomorphology. by RESOURCES Caine and his coworkers (Swanson et al. 1988) claimed that ecosystem behavior Field Techniques can be predicted by a better understanding of how landforms affect those processes. - They noted that landform-ecosystem interactions may take multiple forms, and that Air reconnaissance Chemical tracers Sand/pebble tracers patterns imposed bv one set of interactions may be overridden by another set. The Augering Isotope tracers Water tracing link between landform srabiiity and ecosystem development remains to be quantified. Automatic weather stations Particulate tracers Mass-balance studies Particlefstone shape Petrology Marston (1989, in press) has traced research on the link bemeen sediment transport Dune sand movement Field mapping Resistivity measurements Rock jointing and nutrient export from agricultural and forested ecosystems. No consistent propor- %iVrock creep measurement Seabed drifters Runoff plots tion of nitrogen or phosphorus is released by either sediment loss or dissolution, Frost heave Suspended sediment sampling Soil moisturdtensiodpressure undermining the usefulness of any nonpoint-source models hat rely on this assump- Leveling/surveying Bedload measurement Throughflow me3surement tion. Dendrochronology Solute sampling; conductivity Infiltration measurement Sumecologists have suddenly realized that fluvial geomorphologists can pro- Lichenomeuy GraveVpebble size Aqualung diving vide insights regarding physical habitat features. Working in an interdisciplinary Discharge measurement Seismic survey Ph0tdaSic-streS.S analysis group, Divon and his coworkers (Brussock, Brown, and Dixon 1985) proposed a re- Macrofossils Sounding (lakefsea) Peat boring gional classiticationof stream habitat. It is based on channel form and regular changes ‘Macrofabric OF tills Stone counts Tielapse photography along the longitudinal profile in physical features that comprise rearing habitat (e.g., Dye tracers Stone orientation pool-fle ratios) and spawning habitat (e.g., gravel bars). Laboratory Techniques The extent to which geomorphologists take advantage of this opportunity will depend on their initiative and skill in working with other physical geographers and Air-photo interpretation Heavy-mineral analysis Soil thin sections researchers in engineering and the other natural sciences. Iandsat interpretation Isotope techniques Microfossils The National Aeronautics and Space Administration (NASA) convened an Earth Radar-imagery analysis Hardware simulation Wave-rank models System Sciences Committee (1986). It has recommended a coordinated sequence of Carbon-14 dating Morphorneuy X-ray powder photography specialized space-research missions for studies of Earth-system processes, and an in- Chemical analysis: sediments Pollen analysis X-ray di&action terdisciplinary program of basic Earth-system research in conjunction with other fed- Chemical analysis: water Particle size: sieve X-ray fluorescence Cold Iaboratory expenments Particle size: siltklay Isotope ofwater eral agencies. According to the report, among the many areas to which geographical analysis Digitizer Coulter counter Spectrophotometry geomorphologists can make a contribution are studies of sedimentary processes and DTA Index propenies (Atterberg) Till microlabric biogeochemical cycles. Other opportunities exist for the pursuit of Earth-system sci- Electron microscopy Direct shear box Quantimet analysis ence through the International Geosphere-Biosphere Program (IGBP) of the Interna- Experimental rock weathering Triaxial tests tional Council of Scientific Unions and the Amual Workshop in Earth System Science Flume studies Solution experiments held at Pennsylvania State University. A volume is being prepared jointly by the Institute of Geography at the USSR Numerical Techniques Academy of Sciences and US. geographers, summarizing what is known about the Experimental design specual analysis Directional sratistio geography of change in global-resource systems and major scientific questions within Analysis of variance stochastic processes Informationcontent statistics the goals of IGBP to which geographers may contribute. Some interest has also been Correiation svumres Trend surface analysis D&erential equations errpressed for the formation of an ‘‘Earth System” Specialty Group within the AAG Simple regression Computer mapping Wenergy-balance equations (Borchert 1987). The potenual exists for major contributions to these effortsby geo- Multiple regression Mathematid modeling Thermodynamic models morphologists, by extending their interest in “mega-scale’’geomorphology. Canonical correlation Digital simulation Mainframe computers Wamranalysis Analogue modeling Microcomputers Serial correlation Geomorphic Techniques spaual analysis Geomorphologists have developed a wide range of techniques for data collmion and analysis, including field, laboratoq and numerical techniques (Table 2). hlany of these have been adopted from cognate fields, but all have been used by American geographers in geomorphology. A sampling follows. Several advances in field instrumentation by American geographers in geomorphology have been notable. Leatherman (1978) has devised a low-cost and effective 79 80 81 ~RO~AL.sand tnp for coastal studies (Nordstrom, McCluskey, and Rosen 1986) and desert climates. Butler, Sorenson, and Don (1983) combined geomorphic, stratigraphic, pa- (&,mo~holo~ PROCESSESAND dune studies (Marston 1986b). Toy (1983) developed an instrument for measuring lynologic, and pedologic evidence to discriminate among various types and ages of REso~~ small-scale changes in elevation, as might be required in studies of aeolian erosion- morainic deposits. deposition or frost heave. Graf (1985b) outlined methods for malung geomorphic Three-dimensional fabric analysis has been applied to a wide range of sedimen- measurements from ground-based photographs, a technique he utilized effectively in tary environments bv American geographers in geomorphology. For e-uample, it has other published research (Graf 1978, 1979). Mandel, Sorenson, and Jackson (1985) been applied to sorted stone stripes (Nelson 1982), solifluction lobes (Nelson 1985), described the use of erosion pins to estimate erosion on drastically disturbed lands. hillslope colluvium (Mills 1983), debris flows from Mount St. Helens (Mills 1984), Day (198-t) compared rates of erosion for various carbonate rocks from a wide range glacial till (Mark 1974), and rock glaciers (Giardino and Vitek 1985). Eigenvector anal- of locations through the use of “erosion weight-loss tablets.” Weirich (1984, 1986a) is of fabric data holds promise as a means of daerentiating various types of cobble- designed a network of optical and thermal sensors to document the internal charac- boulder-size deposits when the origin is uncertain. teristics of turbidity and density currents in lakes. A very thorough study bv Dixon, Thorn, and Darmodv (1984) of chemical weath- Field rechniques need greater utilization in two respects. First, a strong need ering on a nunatak of the Juneau Icefield pointed out the importance of dissolution exists for initiating and maintaining long-term field monitoring of geomorphic svs- and clav-mineral transformation in periglacial environments. A convenient chronose- tern, in the tradition of experimental watershed studies that flourished in the 1960s. quence was provided by collecting soil data on successively lower berm levels, which The data set compiled by Caine (1984) over two decades has been invaluable in this were carved into the nunatak during progressive ctownwasting of the adjacent Taku regard The annual cycle common to many funding programs has been a deterrent to Glacier. Divon and his coworkers utilized a variety of laboratory techniques to analyze long-term research. Reoccupying old studv sites is an alternate strategy in some cases, chemical alteration of nunatak gruss and soils, including atomic-absorption spectro- if a mechanism exists to recover former field stations. The ongoing work by Marston photometry (M), X-ray diffraaometry, and scanning electron microscopy (SLM). (1986b) in desert dunes and by Weirich (1987) with fire-related debris flows are ex- Changes in the molar ratios of mobile-to-resistant oxides were used to detect contrast- amples. ing degrees of wathering. The work also highlighted the possible significance of Second, greater use should be made of controlled field-scale experiments. hbo- aeolian inputs of fines to xcount for terrmral and minenlogical anomalies observed rator). studies traditionally yield results that alone have limited applicability at the in the near-surface soil profile. landscape scale. Field studies, without a control on process rates, often frustrate re- Laity (1983) aiso used SEM interpretations to judge the importance of diagenetic searchers who wait for the “characteristic“ event to occur. Results with rainfall simu- controls on groundwater sapping and valley formation in the Colorado Plateau region. lators (eg, Luk, Abrahams,and Parsons 1986; Abrahams, Parsons and Luk 1988; Dolan Morphometric analyses of drainage basins received considerable attention in the and lMarston 1989) and with portable wind tunnels are particularly encouraging. early 1980s. Factors conuolling the direction, density and pattern of channel nemorks The most-recopzed contribution by American geographers to the advancement have been the subject of benchmark papers by Abrahams (e.g., 1980a, 1980b, 1983, of dating techniques is certainly the body of published literature by Dorn and Ober- 1984b) and Abrahams and Ponczynslu (1984). This coherent body of work was rec- lander; their 1982 paper was cited for the GSA Kirk Bryan Award. They have been ognized by the AAG Geomorphology Specdty Group when they presented the G. K responsible for some remarkable developments in the use of rock varnish as an ab- Gilbert Award to Abrahams in 1985. However, early enthusiasm for the use of drain- solute damg tool and as a record of environmental change (climatic and tectonic). age-basin morphometric variables to estimate water and sediment production has Dom and Oberlander were the first to idenufy rock-varnish bacteria in the laboratory. been tempered by the realization that the present-day hillslope and channel nemork They have developed two new rock-varnish dating techniques, radiourbon daung of morphology may include relict components which do not contribute to modem water organics emacted from rock varnish, and cation-ratio dating. They also have utilized and sediment cascades. stable carbon isotopes, micromorphology of dust layers in rock varnish, and micro- Remote-sensing techniques for geomorphologists have been outlined by Rosen- chemical laminations in rock-varnish layers as indicators of fluctuations in climate. feld (1984) and are common tools employed by geographers. Expectations remain Most recently, Dorn (1988) has used rock varnish on Quaternary alluvial fans in high for new appiications in geomorphology as new sensors with improved technol- Death Valley to reveal three cycles of fan development controlled by climatic change *gY are launched. In particular, the remote-sensing platforms now being designed by and tectonic activity. Dom received the 1988 G. K. Gilbert Award for this latest effort. for the Earth Orbiting Space Station of the 1990s will afford opportunities for Geomorphologists worldwide are loolung to Dom and his colleagues for further de- mdY Of mega-scale geomorphology, including catastrophic geomorphic events and velopments in environmental reconstruction using rock varnish. tectonic geomorphology. However, the traditional reliance on expensive and time- Several other studies can be cited to illustrate the range of appiications in geo- consuming field resexch will not be replaced (Graf et al. 1980). morphology using dating techniques. Dendrogeomorphology has been used as a tool Geographers have been somewhat reluctant to utilize numerical techniques, in the anal@ of flooding, mass movement, and rock glaciers (Butler 1979; Shroder given their strong tradition of field work. But some researchers have recognized the and Giardino 1987). Marcus and Marcus (1980) demonstrated the usefulness of strati- hefits of both. Computer-aidedmapping has been utilized more and more for sim- graphic and radiocarbon data from ;1 drained tarn in the reconstruction of Holocene ubLion work (e.g., Band 1985) and erosion mapping (e.g., Marston 1986a; Doh and 82 83 FJMRO~MMarston 1989). A recent book by Kirkby et al. (1987) reviewed computer simulation Faals have already been used with some success in describing coastlines and river Geomorpho,w PROCESSESruvD in physical geography, including the important contributions by American geogra- courses. Sobare is becoming more readily available for research and teaching pur- RESOURCES phers. Cluster analysis has been applied to pollen counts to establish the spatial extent poses (eg, Kirkby et al. 1987). of distinct pollen assemblages (Ellioa-Fisk et al. 1983). Trend-surface analysis has been applied to a wide range of geomorphic environments. For instance, trend-surface mapping of buried organic horizons shows promise The Spatial Theme in Geographical Geomorphology as a tool for recognizing paleosurfaces and separating drift sheets in areas with limited Baker (1986) has noted that regional studies of geomorphology were a major focus subsurface data (Rhoads, Rieck, and Winters 1984). Meierding (1982) used the tech- of geographers until the middle of this century. Comprehensive works on regonal nique to reconstruct the equilibrium-line altitudes of Pleistocene glaciers, and Jones geomorphology have been sparse in the geomorphic literature in North America dur- and Cameron (1977) anal!zed shifts in particle-size characteristics of barrier-island ing recent years, until the appearance of the GSA Cenrennial Special Volume edited sands. The rexiy availabiliry of microcomputers to researchers with the software dis- by Graf (1987a). Nine of the 13 chapters were authored or coauthored by American cussed ab0L-e will conrribute to greater use of numerical modeling in the future. geographers. This excellent compendium avoided descriptive geomorphology in favor of an emphasis on modem process and form, with some reference to earlier time Development of Theory in Geomorphology frames, including the Quaternary. The volume represents an assessment of geomor- phologic theory and a review of selected geomorphic research problems, organtzed Geomorphology has been described zs a “derivative science, borrowing techniques by physiographic province. It represents a modem approach to regional synthesis in and genetalizations from other sciences” (Graf et al. 1980). The belief exists among geomorphology, departing from the more descriptive “physiographv” of the kthalf some geomorphologists that theoretical work is tangential to the mainstream of geo- of this century. morphology. However, a book by Thorn (1988) should help dispel these notions. This Mountain regions have received considerable attention from American geogra- introductory text makes the convincing argument that field work is made more valu- phers in geomorphology, and this attention is deserved. Mountain regions are the able when guided and based upon an established theoretid foundation. Elsewhere, setting for poiygenetic Iandforms and e.memes in rates of geomorphic processes. Thorn has outlined advances in the development of theory with regard to ergodic Applied geomorphologists are noting that mountain regions are being subjected to reasoning, time and space in geomorphology (see Thorn 1982), and landscape evo- population pressures in many regions of the world: for recrexional development and lution. silviculture in the developed world, and for subsistence farming in the developing Geomorphic models have been described as theories or hypotheses about system world The text by Price (198l), Mountains and .Man, provides a particularlv useful form, andlor process, and/or behavior (Woldenberg 1985). Bv this definition, much of synthesis of environmental perception, geomorphology, soils, biogeography,land use, the effort in geomorphology could be considered iz modeling. However, a relatively and humanenvironment relationships. small effort to date l-ras been put forward by geographers seelung a theoretical basis Barsch and Caine (1984) presented a journal-length synopsis of mountain geo- for form and process in geomorphic qstems. Studies of channel networks by faculty morphology, focusing on the high frequency of catastrophic events and the high po- at SUNY-BUffalo and their colleagues are significant exceptions to this trend. For in- tential for accelerated erosion where mountain terrain is impacted by human activity. stance, optimality in network branching phenomena in nature has been addressed by We(1983) also authored a book that epitomizes the “new” process-geomorphobgy drawing analogies between fluvial systems and biological systems (Roy and Wolden- approach to regional studies, summarizing 20 years of work in the mountains of berg 1982: Woldenberg and Horsfield 1983, 1986). Woldenberg (1969, 1979) has also ~OrcheasternTasmania added to our understanding of spatial hierarchies in geomorphology, again with ties A Special issue of the journal Mountain Research and DeYelopment (Ives and Ives to biological systems. 1987) was devoted to an analysis of the ‘Theor). of Himalayan Environmental Degra- However, it appears that greater explanation of channel-network development at dation” which has caused so much alarm and interregional codia. This excellent the landscape scale is being achieved by presuming the operation of stochastic pro- work eqlored whether Current mountain land-use practices produce the downstream cesses than by seeking the deterministic explanation from exact physical-chemid ktfuction accredited to them, and if so, what mitigation measures can be pursued. laws (see, e.g., Abrahams 1984a; Abnhams and Mark 1986). Deterministic models will The Papers in this volume succeed in exposing the problems that result when wide- continue to work best for small-scale studies, but empiricism without prediction is mghg hypotheses are presented as fact, with little geomorphic field data to support still favored by too many geomorphologistswhen their deterministic-modelingeffom them. meet with fiustration. The application of fractal concepts to geomorphic systems has been reviewed by Quatenmy Studies Goodchild and Mark (1987). Fracml surfaces are comprised of values that are depen- dent on neighboring values at all sales. Frad geometry deserves more attention Reconstructing Quatern? environments has been a major focus of interest by her- from geomorphologists as a tool for analyzing various topics-thresholds of erosion geographers in geomorphology (Figure 1). To construct a reliable hypothesis for by overland flow, scales of roughness in hillslope morphology, and numerous others. Past environmental change, the most successful researchers rely on a wide range of 84 85 ~ONMFJL.ITALcorrelative evidence. Work by Holliday (1985a, 1985b) at the Lubbock Lake site in he AAG (Table 3), approximately 90% of which are by American geographers. The &-,~~qhology PROCESSFSAND Texas has signlficance because the sequence at that site is one of the most tightly specialty group also sponsors six or more special sessions each year. Each year since RESOUR- integrated records of late Quaternary human occupance, sedimentation, and soil for- 1983, the AAG Geomorphology Specialty Group has presented the G. K Gilbert Award mation to be documented in North America. Elsewhere in the southern Great Plains, for E?rcellence in Geomorphic Research to the author(s) of a significant recent contri- Hall and Lintz (1984) used a sequence of radiocarbondated buried trees, buried soils, bution to the published literature in the field of geomorphology (Table 4). a carbonate zone, and molluscan fauna to reconstruct climatic variations. The Geomorphoiogy Specialty Group was formed through the elforts of J. D. Butzer's (1981) work in Spain deserves attention because of the varied evidence Vitek and C. E. Thorn in the late 1970s, when geomorphoiogists perceived that they he utilizes to reconstruct a complex sequence of environmental phases: external-sed- were not being included in AAG activities in proportion to their number within the iment flux in karst cave columns, cave slope and roof rubble, chemical precipitates, association (Costa and Graf 1984). This problem is beginning to be addressed by the cryoturbacions, fine soil derivatives, and cultural components. AAG through an increase in the number of physical geographers nominated for AAG Several studies illustrate the complex nature of the environmental change that offices and awards. For instance, the Warren J. Nystrom Award for a paper based on Quaternary scientists are trying to detect and measure. In a study of toposequences dissertation research in geography by a recent Ph.D. recipient has been awarded by of soils under a subalpine forest, Reider (1983) found that the soils are in a state of the AAG to five American geographers in geomorphology: R S. Hayden in 1980, R A disequilibrium with the current environment because of OscilIating ecotones during Marston in 1981, F. H. Weirich in 1984, K K Hirschboeck in 1987, and D. W. ,May in the Pleistocene and Holocene. Knox, McDowell, and Johnson (1981) reconstructed 1988. the magnitude and causes of floods over the last 10,000 years for the Drifrless Area of Wisconsin, an area where controversy remains regarding the effects of continental The GSA Quaternary Geology and Geomorphology Division glaciation. Working in the same area, McDoweIl (1983) demonstrated the episodic The Quaternary Geology and Geomorphology Division of the GSA provides a forum nature of stream response to changes in climate and during the Holocene. vegetation for 1,435 members (October 1987), ranking third in size among the 10 divisions of Miller (1985) utilized 40 years of data from the Juneau Icefield to reconstruct has the GSA A large number of geomorphology papers are presented at the annual meet- pdeoenvironments in southat Alaska during late Neoglacid times. The stud?' was ings (Table 3, approximately 10% by American geographers. exceptional in the way it used,multidisciplinary data sets to eventually explain glacier response to the complex interactions of astronomical, geophysical, atmospheric. oceanic, and anthropogenic factors. Table 3 ~mlpholoeypapen presented at AAG and GSA meeting Year AAG GSA Year MG GSA Year AAG GSA PROEESSIONAL AFFILIATIONS FOR AMERICAN GEOMORPHOLOGISTS 1976 16 44 1980 61 n 1984 86 81 1977 56 30 1981 71 72 1985 60 95 The principal professional organizations for American geographers in geomorphology 1978 76 49 1982 ?-i 66 1986 72 89 are the Geomorphology Specialty Group of the AAG, the Quaternary Geology and 1979 62 62 1983 70 47 1987 86 124 Geomorphology Division of the GSA, the American Quaternary Association, and the Mean 65.8 69.7 Soil Science Society of heria The American Geomorphological Field Group and Sour~: for the perid from Casts and Gnf (1%). Friends of the Pleistocene hold fieid-oriented meetings. Data 1976-80 Ample opportunities for interaction with foreign colleagues across the subfields Table 4 of geomorphology is provided by the Annual Binghamton Geomorphology Symposia. Reapients of the G. K. Gilbert Award, presented by the MG Geornorphology Speclalrv Group the British Geomorphological Field Group, the Guelph Symposia on Geomorpholog)l, the International Conferences on Gmmorphology, the International Quaternary As- Year Recipient Contribution to Geomorphology sociation, the International Geographical Union, the International Symposium on Ero- 1983 J. Rw Permafrost studies in the MaCkelYZie fier delta are;l sion and Sedimentation in the Pacific Run, and the International Union of Geological 1984 WdGd Fluvial processe in the southwest United states Sciences. In addition, a great number-too numerous to list-f one-time topical 1985 AtholAbtahamS' Channelnetworks symposia that are of interest to geomorphologists are offered each year. 1986 Karl Buaef' Archaeology human e~ology 1987 DerekFord Karst geomorphology and Quaternaty chronolcgies in the The MGGeomorphology Specialty Group castleguard cave area of the Canadian Rockies 1% RonDorna The Geomorphology Specialty Group of the AAG provides a forum for 268 members The use of rock varnlsh to distinguish three! episodes of alluvial fan development in Death Vdey (May 1987 data), ranking ninth in size among the 38 specialty groups in the association. Geomorphologists present a large number of papers at the annual meetings of geographers 86 The division presents several prestigious awards, with an occasional American -0-u 5 PROCESSESW geognpher a recipient. The Distinguished Career Award was first presented in Table xi fie Binghamton Symposia in geomorphology REsou’R~ 1986. The Kirk Bryan Award is presented for an outstanding paper in Quaternary geology and geomorphology; the 1986 award was presented to R I. Dorn and T. M. Contributors: Oberlander for their 1982 paper, “Rock Varnish.” Amer; can The Gladys W. Cole Memorial Research Award is used to support the investigation YCU Geographers/ Topic Editor(s) Total of the geomorphology of semiarid and arid terrains in the U.S. and Mexico. It was qo. Held awarded to W. L Graf in 1984 to support his study of radionudides in dryland rivers, 1 1970 Environmental Geomorphology D. R Coates 2 18 and to A D. Abrahams in 1985 for use in his studies of rock-slope form in the Mojave 2 1971 Quantitative Geomorphology M. Morisawa 2 12 Desert (see Abrahams and Parsons 1987). 3 1972 Coastal Geomorphology D. R Coates 2 16 The Robert K Fahnestock Award is presented to the applicant having the best 4 1973 FluviaI Geomorphology M. Morisawa 1 20 proposal in sediment transport or related aspects of fluvial geomorphology. It was 5 1974 Glad Geomorphology D. R Coates 0 16 awarded to R Andtle in 1987 for his study of pools and riffles in low-sinuosity alluvial 6 1975 Theories of Landform Development W. N. Melhom and 2 16 R C. Fled sum. D. R Coates 0 20 The division also awards two Mackin Grants each year for support of graduate- 7 1976 Geomorphology & Engineering Geomorphology in Arid Regons D. 0. Dcehg 1 19 student research in Quaternary geology and geomorphology, one award to a master’s 8 1977 9 1978 Thresholds in Geomorphology D. R Coam and 2 29 student and one to a doctoral student. Mark Gonzalez (University of Wisconsin-Mad- J. D. Vitelf ison) and Dorothy Sack (University of Urah) are two geography students in American 10 1979 Adjusments of the Fluvial System D. D. Rhoda and 2 25 universities who have been selected for Mackin Grants in recent yem. E. J. Williams 11 1980 Applied Geomorphology R J. Craig and J. L 1 33 The Binghamton Symposia in Geomorphology Craft 12 1981 Space & Tie in Geomorphology C. E. Thoma 4 20 The First Geomorphology Symposia in 1970 was organized and hosted by Donald R 13 1982 Groundwater as a Geomorphic Agent R G. LaFleur 1 19 Coates and Marie Morisawa at SUNY-Binghamton. After a long tenure on that campus, 14 1983 Models in Geomorphology M. J. Woldenberga 1 31 the annual event has been moved to other locales, but the name “Binghamton Svm- 15 1984 Tectonic Geomorphology M Morisawa and 3 22 posh in Geomorphology”has become associated with this distinguished international, J. T. Hack interdisciphry meeting. American geographers have contributed 9.5% of the papers 16 1985 Hillslope Processes h D. Abvlrahams’ 2 28 delivered and later published by the symposia (Table 5). Four of the 18 volumes have 17 1986 Aeolian Geomorphology W. G. Nidding a 2: L Mayer md D. Nash 4 2: utilized American geographers as editors: 7?n-&U in Geomorphology by Coates and 18 1987 catastrophic Flooding Vitek (1980b), S’e and Time in Geomwphology by Thorn (1982), Models in Geo- ‘American geographers morphology by Woldenberg (1985), and Hillslope procesreS by Abrahams (1986). Morphotectonics(1980) International Geomorphology Activities Geomorphologid Survey and Mapping (1968) Man’s Impact on Karst Areas (1984) The International Geographical Union holds a congress every four years. Immediately before the main congress, and in years between the main congresses, IGU commis- At the 1988 IKin Sydney, 12 of the 112 geomorphology Wrdposters presented sions, working groups, and study groups meet at separate venues to examine past and were authored by American geographers. ongoing research in the field and to hold more formal paper sessions. The commis- Much exatement has been generated over the prospect of an international ow- sions, working groups, and study groups operating as of 1988 that are of interest to -tion for geomorphologists.In September 1985, the British Geomorphologid Re- geomorphologists are listed below, with the date they were established (Walker 1987): Search Group hosted the First International Conference on Geomorphology in Man- ckser; England. It was attended by 675 ge6morphologists from 51 countries. Moist in Measurement, Theory,and Application in Geomorphoiogy (1968) amdance agreed that an international organization was desirable (Sugden 1987). A Mountain Geoecology (1976) committee was formed to explore the ramifications of atablishing an organimfion, Coastal Environment (1952) and its findings will be reported z the Second Conference, to be held in West Ger- The Sigdicance of Periglacial Phenomena (1949) in 1989. International Hydrological Programme (1964) Meanwhile, a Newsletter and World Directory of Geomorphologists are being Geomorphology of River and Coastal Plains (1980) developed. The Proceedings of the First Conference have been published by wilq

87 88 ~0~~ and Sons (Gardiner 1987) in two volumes, totaling 2530 pages. Abrahams (1987), EVALUATION AND PROSPECTS PROCESSES AND Psuty and Allen (1987), Sherman (Sherman and Greenwood 1987), and Walker (1987) RESOURCES each published a paper on behalf of American geographers from a total of 78 presen- mericm geographers worhng in geomorphology todav benefit from paradigms that tations by American geomorphologists. provide a broad scientific foundation for the discipline. American geographers in geo- Walker and Orme (1986) have summarized the prominent themes of the meeting morphology have never before had so many opportunities for presentation and pub and arrived at two main conclusions: first, geomorphology remains a field-oriented liation of research. Geographers are publishing at a high rate compared to the over- discipline, although laboratory experiments and theory development are increasing in all number of geomorphologists, and they are making important contributions beyond importance. Second, geomorphoiogy is a global science, in the sense of interest he scope of geographic inquiry. worldwide, and participation by American geographers must be increased. mile gaining new perspectives from greater international collaboration and interaction with geomorphologists from other backgrounds, geographical geomorphol- ogisrs need to leave an imprint on the study of landforms and soils that reflects their GEOMORPHOLOGY IN EDUCATION vaidng as geographers. Geomorphology is undergoing a reorganization that may mask the identity of Americm geographers within geomorphology, but the need will The dedine of both field geology and the number of geomorphologists associated remain for certain contributions that are best supplied by those possessing a back- with acrdemic geology units has been noted by Costa and Graf (1984). k the same ground in geography. The synthesis. integration, and predictive spatial modeling that time, geomorphology has gamed in strength within geography departments at the mark geomorphic research by geographers are imprints that should be emphasized university level in the US. Vitek (1988) ascribes this shift to the dynamic growth in ar a time when pluralism exists in the discipline. Unfortunately, geographers are miss- the petroleum industry, hydrogeology, sedimentology, and engineering geology, ing an opportunity to leave a distinct imprint on the studv of landforms and soils by which has attracted geology students away from potential careers in geomorphology. often pursuing research that duplicates the objectives of geologic inquiv. To explain the lack of support for geomorphology by other geology faculty, Ritter The strongest contributions by American geographers to the discipline will be in (1988) cited a “lack of unity” in the discipline caused by the dichotomy of purpose studies that refine existing paradigms; link measurement, theory, and application; sep- (historical versus process-oriented studies) and vagueness of paradigms. Actually, the menatural and human-triggered txiation in geomorptuc systems; and pursue land- dichotomy of purpose to which Ritter refers is part of the pluralism chmed as a scape ecology and Earrh-s)stem science. Geographers will continue to contribute their strength of the discipiine by others. Moreover, paradigms in geomorphology have fair share toward the development of research techniques in geomorphology and been smted most succinctly by a geologist (Schumm 1977). His arricle is addressed to toward the differentiation of geomorphic systems in time and space (i.e., Quatenmy other geoscientists who may “cling to ideas which lend themselves to easy pedagogy studies and regional geomorphology). but are possibly wrong and certainly do not reflect geomorphic science as it is today More theoreticians are needed among the ranks of American geographers in geo- or what it will be like in the future.” morphology. Long-term field monitoring of geomorphic s).stems is desired to berter Mawhile, several generaions of students in geography have emerged 3s re- understand adjustment of form and process over the scale of decades. And greater search professors in geomorphology, thanks to a tradition of inspiration that began dimce on controlled field-scale experiments is urged, to achieve more meaningful with their mentors during the “quantitative revolution” in geomorphology in the results at a scale that can link labomtory and landscape scales of understanding in 1950s. iMarcus (1979a) noted that “empioyment opportunities have been good [and] geomorphology. basic and applied research has thrived” for physical geographers. In terms of employ- New introductory tern in geomorphology, autfiored by American geographers, ment, 74% of American geographers in geomorphology are employed by universities, are desired to advance the themes of geographical geomorphology in education. 11% are employed in the private sector (including self-employed), and 9% are em- Fdy, American geographers in geomorpholow must seek more interaction with ployed by federal and state governmental agencies. Given & situation, it is somewhat their colleagues on an international level and publish more in the high-impact-factor surprising char, of the 191 U.S. universities that list depment specialties in the 1987- bumah to ensure their efforts receive the widest recognition. 88 Guide to Dqxrrtments of Geography in the United Smes and ~~, only 72 lit geomorphology and 33 list soiis as department specialties. A glaring omission by American geographers has been their failure to author new REFERENCES introductory texts in geomorphoiogy. The most recent effort was by Butzer (1976), distinguished from other texts by weaving dynamic geomorphology into a regional &brahams, A D. Channel link density and . 1983. Geological controls on the topologic frameworkHowever, the themes in geomorphology toward which American geomor- 19W ground slope. .-\nnaLs of the Association of Amerf- properties of some treUis channel networks. Bulle- phologists are making significant contributions are not well represented in the te.m Geographers 70:80-93. tin of &beGeologiculSoc&y 0f.lmeriCa 9480-91. are receiving widest adoption-those authored by geologists. Similarly, American that -. 1980b. Divide angles and their relation to inte- -.1984a Channel networks: h geomorphological geographers contribute few anicles on the teaching of geomorphology to the Journal rior link lengths in natural channel networks. GO perspve. Water Resources Resemrb 20161-88. of Gmgrapky and the Journal of Geological Edmtzon. graphicar AnulisiS 12157-71. 89 . 1984b. Tributary development along winding Channel form and stream ecosystem models. Wu- my,M. J. 1983. Slope form and process in cockpit karst GnE, W. L 1978. Fluvial adjustments to the spread of streams and valleys. rlmericnn Journal of Science ter Resources Bulletin 21:859-66. in Belize. In Nerv directions in karst, eds. K. Pater- tamarisk in the Colorado Plateau Region. 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