bioprotection explored the story of a little known earth surface process abstract bioprotection is identified as an earth surface process however it has been little studied little acknowledged and yet may have major implications for the operation and management of geomorphic systems key early observations are traced back to darwin s voyage of the beagle geikie in the natural environment and watson for the built environment recent field observations and experimental work examining bioprotection are reviewed with a specific focus on lichens and the landscape as are its complex interactions with other processes a conceptual model of bioprotection is presented for the case of an epilithic lichen on a limestone surface

biogeomorphology revisited looking towards the future although biogeomorphological research is well established with many studies on a range of two way interrelations between organisms and geomorphology in different environments there is little consensus over what constitutes biogeomorphology why it might be useful and where it is heading starting with definitions of core biogeomorphic processes we consider the need for future biogeomorphological studies to evaluate the crucial links between bioprocesses biological community dynamics and inorganic earth surface processes five key applications of biogeomorphological research are identified the roles of organisms in environmental reconstruction trace fossil analysis extraterrestrial geomorphology environmental engineering and the built environment some key research directions and methodological challenges for future biogeomorphological research include expanding the spatial and temporal coverage of datasets investigating the role of bioprocesses in landform development tackling scale issues investigating the relevance of nonlinear dynamical ideas to biogeomorphology and developing better sampling and monitoring techniques for bioprocesses

continual erosion of bare rocks after the wenchuan earthquake and control strategies abstract the newly bared rocks created by the wenchuan earthquake are undergoing continual intensive erosion in the form of detachment and movement of individual grains grain erosion is defined as the phenomenon of breaking down bare rocks under the action of insolation and temperature change detachment of grains from the rockwalls by wind flow down of grains on the slope under the action of gravity and accumulation of grains at the toe of the mountain forming a deposit fan the wenchuan earthquake which occurred in sichuan on may 12 2008 caused thousands of avalanches and landslides and left scars on slopes and a huge area of bare rocks grain erosion causes flying stones injured humans and resulted in numerous slope debris flows the process of grain erosion and strategies to limit the erosion were studied by field investigations and field experiments according to these field investigations and field studies the most serious grain erosion occurs in spring and early summer when it is very dry rocks are broken down to grains under the action of insolation and temperature change then wind blows the grains from the bare rock down slope experimental results showed that the amount of grains blown down by wind per area of rock surface per unit time is proportional to the fourth power of the wind speed however the size of the grains blown down by wind increases linearly with the wind speed an experiment proved that grain erosion can be controlled with two moss species moss spores were mixed with clay suspension and splashed on bare rocks the moss species germinated on the rock surface in one month and greened the bare rocks in two months the moss layer protected the rocks from insolation and mitigated the effects of temperature change thus effectively mitigated grain erosion

simulation and projection of circulations associated with atmospheric rivers along the north american northeast coast abstracttorrential rainfall occurring along the north american northeast coast nanc in summer and autumn is accompanied by strong atmospheric rivers ars which efficiently transport abundant mo

river discharge influences on particulate organic carbon age structure in the mississippi atchafalaya river system 1 applying ramped pyrolysis radiocarbon analysis to suspended river sediments we generate radiocarbon 14c age spectra for particulate organic carbon poc from the lower mississippi atchafalaya river system mars to better understand a major river system s role in carbon transport ramped pyrolysis 14c analysis generates age distributions of bulk carbon based on thermochemical stability of different organic components our results indicate higher proportions of older material in the poc during higher discharge ages increase throughout the high discharge age spectra indicating that no single component of the poc is responsible for the overall age increases observed instead older material is contributed across the poc age spectrum and unrelated to increased bedload suspension in this comparison of 2 spring discharges less than half of the poc transported during higher discharge is less than 1000 14c years in age constraining of the role of the mars as a flux of atmospheric co2 toward longer term sedimentary sinks in the mississippi delta and the gulf of mexico the results suggest that delta building processes benefit disproportionately from high discharge events carrying larger amounts of sediment because these events involve both a higher proportion of millennially aged carbon from floodplain exchange of poc and a potentially higher proportion of petrogenic carbon 30 530 increase overall an internally consistent picture of po14c age distributions from a major river system emerges as differences in space and time are small compared to the range of ages of poc sources in such a large basin

bioprotection and disturbance seaweed microclimatic stability and conditions for mechanical weathering in the intertidal zone as well as their destructive roles plants animals and microorganisms contribute to geomorphology and ecology via direct and indirect bioprotection which can reduce weathering and erosion for example indirect bioprotection can operate via biotic influences on microclimate whereby physical decay processes associated with fluctuations in temperature and moisture salt crystallization thermal fatigue and wetting drying are limited in the intertidal zone the spatial and temporal distribution of macroalgae seaweeds is patchy related to physical and ecological conditions for colonization and growth and the nature and frequency of natural and anthropogenic disturbance we examined the influence of seaweed canopies fucus spp on near surface microclimate and by implication on conditions for mechanical rock decay and under canopy ecology monitoring on hard artificial coastal structures in south west england uk built from limestone and concrete showed that both the range and maxima of daily summertime temperatures were significantly lower by an average of 56 and 25 respectively in areas colonized by seaweed compared to experimentally cleared areas short term microclimatic variability minutes hours was also significantly reduced by an average of 78 for temperature and 71 for humidity under algal canopies during low tide events using seaweed as an example we develop a conceptual model of the relationship between biological cover and microclimate in the intertidal zone disturbance events that remove or drastically reduce seaweed cover mediate shifts between relatively stable and unstable states with respect to mechanical decay and ecological stress associated with heat and desiccation in urban coastal environments where disturbance may be frequent facilitating the establishment and recovery of canopy forming species on rocks and engineered structures could enhance the durability of construction materials as well as support conservation planning and policy targets for biodiversity enhancement

geomorphological implications of engineering bed sediments by lotic animals abstract recent developments in zoogeomorphology in combination with the increasing interest of ecologists in ecosystem engineering by organisms initiated considerable research on the impact of running water i e lotic animals and other organisms on fluvial bed sediments and the transport of solids this research provided multiple evidence from field and laboratory observations and experiments that many species among mammals amphibians fish insects crustaceans mollusks and worms engineer bed sediments of running waters with diverse mechanistic tools thereby perturbing or consolidating the sediments in many types of running waters across continents seasons habitat types particle sizes and discharge levels baseflow vs flood furthermore many animals modify the bed sediment engineering by plants algae larger macrophytes riparian vegetation modeling effects of bioturbating lotic animals across species and relatively simple environmental conditions in mesocosms provided highly significant results p range

wind as a cooling agent substrate temperatures are responsible for variable lithobiont induced weathering patterns on west and east facing limestone bedrock of the negev spatial variability in lithobiont induced weathering patterns on desert rocks is aspect dependent while differences between the northern and southern aspects have been extensively studied little is known concerning the differences between east facing ef and west facing wf aspects in deserts including the negev desert whereas cobbles on both slopes are inhabited by endolithic lichens epilithic lichens which render the bedrock a smooth appearance and free living cyanobacteria which give the bedrock a rugged microrelief predominate on wf and ef bedrock respectively following previous research that regarded dew as the principal factor that determines lithobiont distribution measurements of radiation temperature wind and dew were carried out during 2008 2009 in the negev desert the data indicated that albeit slightly higher midday surface temperatures that characterize wf surfaces cobbles and bedrock nocturnal temperatures on these surfaces were significantly lower therefore facilitating higher dew condensation high amounts of dew result from the relatively rapid drop in temperatures 14 00 20 00 due to the afternoon northwesterly sea breeze wind with a cooling rate of the wf bedrock being 52 9 higher than on ef bedrock 2 6 c h 1 in comparison to only 1 7 c h 1 and facilitate the growth of high chlorophyll dew fed and rain fed epilithic lichens which may act as bio protectors on wf bedrock lack of condensation on ef bedrock results in turn in the growth of rain fed free living cyanobacteria responsible for high rock dissolution and subsequently for a rugged microrelief by affecting the nocturnal bedrock temperatures wind acts as a cooling agent impacting in turn the amount of dew and subsequently lithobiont composition and weathering patterns in the negev desert copyright 2016 john wiley sons ltd copyright 2016 john wiley sons ltd

microscale biopitting by the endolithic lichen verrucaria baldensis and its proposed role in mesoscale solution basin development on limestone data are reported demonstrating the potential role of microscale morphologies induced by endolithic lichen communities specifically verrucaria baldensis in the initiation and development of mesoscale solution basin formation on limestone in the burren county clare a biophysical model is proposed outlining the different microscale stages leading to solution basin initiation with a progression from initial lichen colonization and growth associated perithecial biopitting followed by biopit coalescence to form biotroughs their subsequent enlargement and eventual incipient solution basin formation this model provides one explanation for solution basin development as this end state may also be achieved through simple solutional means without biological input the complexity of interactions at the lichen rock interface are identified with emphasis on the spatial and temporal variability of these underlining the point that as with macrotopographies at the landscape scale rock surface microtopographies also reflect historical weathering legacies copyright 2011 john wiley sons ltd

mid holocene grounding line retreat and readvance at whillans ice stream west antarctica author s venturelli ra siegfried mr roush ka li w burnett j zook r fricker ha priscu jc leventer a rosenheim be

surface hardness as a proxy for weathering behaviour of limestone heritage a case study on dated headstones on the isle of portland uk this study estimates stone weathering rates using in situ surface hardness testing surface hardness changes are precursors to erosion and may be utilized to describe stone weathering behaviour the method proposed here complements previous approaches to determining stone weathering rates by surface loss change a time series covering 1 248 years of exposure is investigated using a sample of 12 headstones in two nearby cemeteries using an equotip d surface hardness tester rates of change in surface hardness for top and bottom sections of the headstones were determined and the data evaluated using robust nonparametric statistical methods when considering all headstones as one time series nonlinear behaviour is observed with rates of decline in surface hardness slowing over time however breakpoint analysis shows a breakpoint at c 100 years with higher rates of surface hardness decline as measured by qc 50 the regression coefficient for 0 50 quantile regression up to that point and lower rates thereafter up to c 100 years surface hardness declines more rapidly in the top versus bottom sections possible explanations for the differing rates in surface hardness changes are a inherent natural stone variability and or different weathering stress history b the use of two different portland limestone varieties c synergistic effects of microclimates and lichen cover in order to gain a deeper insight into stone weathering behaviour future studies could combine surface hardness measurements with surface change methods such as micro erosion meter and lead plug index over short and long term time series on architectural heritage under real world conditions

evidence for permafrost thaw and transport from an alaskan north slope watershed burial of organic carbon oc in marine sediments is one of the most important linkages between the short term biologic carbon cycle and the long term geologic carbon cycle yet much is still unknown about the fate of terrigenous oc in marine coastal margins here the delivery of particulate oc poc to the colville river deltaic region in the alaskan beaufort sea by particulates of varying densities is studied through the use of ramped temperature pyrolysis and radiocarbon analyses the colville river is the largest river in north america whose watershed is underlain completely by high arctic permafrost tundra a variety of sources of poc are considered including terrestrial soils pleistocene aged yedoma like sediments coastal peat erosion and marine poc we provide the first evidence that riverine poc from the colville river contains old pleistocene sourced oc suggesting ongoing thaw and mobilization of yedoma like permafrost oc from this northern alaskan watershed additionally much of this oc appears to be fairly labile and therefore could be readily oxidized and returned to the atmosphere

crayfish and fish as bioturbators of streambed sediments assessing joint effects of species with different mechanistic abilities abstract many studies illustrate that bioturbating animal species individually affect aquatic sediments through diverse mechanistic abilities whereas assessments of joint effects of such species on sediments are relatively rare such joint effects have implications for real systems in which different bioturbators coexist but are difficult to predict for two reasons first they can be additive being the sum of the individual effects of each species or they can be positive or negative interactive being greater or smaller than the sum of the individual effects second if interactive they can depend on biotic interactions that affect the bioturbating activities of the species and or they can depend on physical interactions among bioturbator induced sediment modifications using experimental streams we assessed such joint effects on gravel sand sediments for flow and sediment conditions preferred by barbel barbus barbus but also used by gudgeon gobio gobio and in a second experiment for flow and sediment conditions preferred by both male crayfish orconectes limosus and gudgeon these species have different mechanistic abilities to affect gravel and or sand in stream beds in each experiment we measured i the transport of gravel and sand at baseflow during 12 experimental days ii four sediment surface characteristics after 12 d and iii the critical shear stress c causing incipient gravel and sand motion during experimental floods after 12 d gudgeon contributed differently to the joint effects in the two experiments which related to its individual weight prevailing baseflow shear stress sediment particle weight and sediment mixture availability of surface sand overall the species pairs had predominantly negative interactive joint effects on the sediment variables assessed by us both a literature survey and observations during the experiments provided no evidence for direct biotic interactions between barbel and gudgeon or crayfish and gudgeon so one would reasonably associate their negative interactive effects on the sediments with physical interactions among bioturbator induced sediment surface modifications individually each species reduced the percentage of sand in the surface layer and the surface algal cover to relatively low values so that the species pairs could not accomplish much greater joint effects on these variables explaining their negative interactive effects on them as algal cover particularly affected the c for gravel and sand the negative interactive effects of the animals on this surface variable chained toward the c for the sediments on which the species pairs also had negative interactive effects such chained negative interactive effects on sediment variables are seemingly a general pattern of joint bioturbator effects on aquatic sediments i e the many so far described single species effects should be smaller than their sum if the species coexists in nature

interaction of geomorphic and ecologic features across altitudinal zones in a subarctic landscape abstract vegetation is often considered to stabilize geomorphic processes an increasing abundance of vegetation may cause negative feedbacks within a periglacial system in this study we explored the importance of vegetation on the occurrence of active cryoturbation dominated feature fields in subarctic finland on a landscape scale the vegetation cryoturbation interaction was studied across three altitudinal zones by applying hierarchical partitioning hp and variation partitioning vp methods that overcome collinearity problems in multivariate analysis firstly our results showed that vegetation factors especially the canopy cover of the field layer vegetation and the total above ground biomass were among the most important environmental variables affecting the occurrence of active cryoturbation features moreover vegetation factors were for the most part positively associated with cryoturbation under the predicted global warming the greening of arctic and subarctic regions may therefore decrease and also increase the activity of the periglacial processes in sparsely vegetated terrain secondly our analyses gave contrasting results of the environmental factors of the periglacial processes across altitudinal zones although the relative importance of the vegetation group was rather constant throughout the zones thus we stress the importance of the spatial study setting in geomorphic studies in topographically varying relief we recommend either taking the altitudinal zonation of the landscape into consideration or studying the features within a predetermined zone to decrease misinterpretations in environment process relationships methodologically our results encourage wider applications of partitioning methods in multivariate settings in geomorphology

sediment deposition at the modern grounding zone of whillans ice stream west antarctica 1 much of the threshold behavior of marine ice sheets is thought to result from processes occurring at the grounding zone where the ice sheet transitions into the ice shelf at short timescales decades to centuries grounding zone behavior is likely to be influenced by ongoing sediment deposition which can stabilize the grounding zone position we present a ground based geophysical study across the modern grounding zone of whillans ice stream within an embayment setting where subglacial meltwater drains we image sedimentary deposits however we do not observe the classic asymmetric grounding zone wedge deposits which are found in the paleorecord and are thought to stabilize the grounding zone position at an adjacent peninsula we image the grounding zone and an ice shelf pinning point and again observe no wedge deposits

incipient weathering by stereocaulon vulcani at reunion volcanic island abstract the impact of early land plants and fungi in increasing global weathering is still debated particularly before the advent of vascular plants during the devonian here we present a study of the incipient weathering of basalt by stereocaulon vulcani a native colonizing lichen on reunion island indian ocean we analyzed the chemistry and mineralogy of a 24 year old flow located at low altitude that was mostly covered by s vulcani with aboveground biomass of 6249 kg ha 1 the chemical composition of s vulcani showed that besides c and n si and fe were the dominant elements the si stored in the aboveground pioneer vegetation gives 27 kg ha 1 comparable to the si stored in the old growth at the marelongue reserve meunier et al 2010 on thin sections the inner part of s vulcani was mostly composed of si while fe coatings observed at the base of the thallus may be the result of wind blow dust interception as suggested by cochran and berner 1992 using bse images on sem we showed evidence of dissolution of the glass matrix at the basalt thallus contact the quantification of porosity by digital imagery showed a variation between 7 in the unweathered zone to near to 40 at the surface a maximum denudation rate of 6 7 m year 1 is estimated to fall within the range of the values reported in the literature using our data for analog to the past we suggest that early land plants would have been capable to mobilize si in a similar proportion as vascular plants and should have significantly affected the weathering of land before the advent of vascular plants

the effects of lichen cover upon the rate of solutional weathering of limestone abstract the contribution of lichens to the biomodification of limestone surfaces is an area of conflict within bioweathering studies with some researchers suggesting a protective effect induced by lichen coverage and others a deteriorative effect induced by the same organisms data are reported demonstrating the potential role of endolithic lichen in particular of bagliettoa baldensis in the active protection of carboniferous limestone surfaces from rainfall induced solutional weathering during a 12 month microcatchment exposure period in the west of northern ireland average dissolutional losses of calcium are greater from a lichen free limestone surface compared with a predominantly endolithic lichen covered surface by just under 1 25 times during colder winter months the lichen free surface experiences calcium loss almost 1 5 times greater than the lichen covered surface using extrapolation to upscale from the micro catchment sample scale for the year of sample exposure the rate of calcium loss is 1 001 g m 2 a 1 from lichen covered limestone surfaces and 1 228 g m 2 a 1 from lichen free bare limestone surfaces this research has implications for our understanding of karst environments the contribution of lichens to karren development and the conservation of lichen colonised dimension stone within a cultural setting

antarctic sediment chronology by programmed temperature pyrolysis methodology and data treatment 1 we report a detailed programmed temperature pyrolysis combustion methodology for radiocarbon 14c dating of antarctic sub ice shelf sediments the method targets the autochthonous organic component in sediments that contain a distribution of acid insoluble organic components from several sources of different ages the approach has improved sediment chronology in organic rich sediments proximal to antarctic ice shelves by yielding maximum age constraints significantly younger than bulk radiocarbon dates from the same sediment horizons the method proves adequate in determining isotope ratios of the pre aged carbon end member however the isotopic compositions of the low temperature measurements indicate that no samples completely avoided mixing with some proportion of pre aged organic material dating the unresolved but desired young end member must rely on indirect methods but a simple mixing model cannot be developed without knowledge of the sedimentation rate or comparable constraints a mathematical approach allowing for multiple mixing components yields a maximum likelihood age a first order approximation of the relative proportion of the autochthonous component and the temperature at which allochthonous carbon begins to volatilize and mix with the autochthonous component it is likely that our estimation of the cutoff temperature will be improved with knowledge of the pyrolysis kinetics of the major components chronology is improved relative to bulk acid insoluble organic material ages from nine temperature interval dates down to two but incorporation of inherently more pre aged carbon in the first division becomes more apparent with fewer and larger temperature intervals

rock protecting seaweed experimental evidence of bioprotection in the intertidal zone biogeomorphological processes are an important component of dynamic intertidal systems on rocky shores the direct contribution of microorganisms plants and animals to weathering and erosion is well known there is also increasing evidence that organisms can alter rock breakdown indirectly by moderating temperature and moisture regimes at the rock air interface these influences have been purported to represent mechanisms of bioprotection by buffering microclimatic fluctuations associated with weathering processes such as wetting and drying and salt crystallization however virtually nothing has been done to test whether microclimatic buffering translates to differences in actual rock breakdown rates here we report a preliminary laboratory experiment to assess how an artificial canopy chosen to represent seaweed affects mechanical rock breakdown using a simplified and accelerated thermal regime based on field data from a rocky shore platform in southern england uk we find that breakdown mineral debris release of mudstone covered with a canopy is reduced by as much as 79 relative to bare rock after around 100 thermal cycles reduction in rock surface hardness measured using an equotip device was also greater for bare rock 17 compared to covered rock 10 over this period measurements of salt crystal formation indicate that the mechanism driving these differences was a reduction in the frequency of crystallization events via moisture retention and shading of the rock surface copyright 2015 john wiley sons ltd

contrasting weathering and climate regimes in forested and cleared sandstone temples of the angkor region comparative assessment of stone weathering intensities and bioclimatic conditions was conducted at four temples located in cleared and forested sites of the angkor park based on similar protocols four thousand sculpted lotus petals carved in the same grey sandstone were categorized by using two customized scales of weathering intensity and climate monitoring was conducted from december 2008 to november 2009 whereas 70 of the sandstone lotus petals are almost completely destroyed by mechanical weathering in cleared areas 74 of petals located in forested environments appear to be totally free of mechanical weathering and are only affected by superficial biochemical weathering ambient conditions are also contrasting with the magnitude of the diurnal surface temperature and relative humidity ranges being three times higher at cleared sites than in wooded areas as wetting drying cycles are the driving force of sandstone decay at angkor causal links are suggested between weathering and climate regimes in wooded areas the microclimate is buffered by the forest and the associated lithobionts which maintain constant humidity levels reduce thermal stresses at the stone surface and induce a slow biochemical weathering regime in cleared areas direct exposure to sunshine and monsoon rains induces pronounced wetting drying cycles conducive to swelling shrinking movements and other potential processes provoking the rapid mechanical decay of the sandstone even if local damage can be caused by tree roots the forest cover and the associated lithobionts obviously play an overall protective role additionally microtopographical factors related to architectural designs and post building events probably explain intra site and between site minor differences in the amount of sandstone decay by influencing key factors such as the water residence time at the stone surface last the contrasting weathering regimes in forested and cleared sites are but a trend for besides overwhelming mechanical weathering chemical weathering is also operative at cleared sites as indicated by salt efflorescences and ferric oxidation copyright 2012 john wiley sons ltd

morphological features and processes in the central algarve rocky coast south portugal morphological features along the algarve rocky coast south portugal are identified and described with an emphasis on shore platforms and notches the contributions of processes such as wave attack chemical weathering and bioerosion to sculpting the shore platforms are discussed the preferential localization of shore platforms on sites exposed to waves and the lack of significant chemical weathering point to wave erosion as the first order factor in platform formation whilst bioerosion bioprotection lithology and geological structure determine platform morphological variations in addition platforms above the present intertidal zone appear to have a polygenetic evolution being inherited from former sea level highstands and currently undergoing chemical weathering the occurrence of notch features is independent of the degree of exposure to waves but they mostly occur where the substratum is sand hydrostatic pressure appears to be an important factor in the formation of marine caves in the more sheltered sites

schmidt hammer studies in the maritime antarctic application to dating holocene deglaciation and estimating the effects of macrolichens on rock weathering in order to contribute to the reconstruction of the deglaciation history of the marguerite bay area 68 s maritime antarctic and to estimate the rock weathering rate in this antarctic sector 28 sites 7 on rothera point and 21 on anchorage island were characterised using schmidt hammer values the weathering effect of two of the most widespread species of macrolichens in this area usnea sphacelata and umbilicaria decussata was tested at 5 different sites on rothera point schmidt hammer data in conjunction with recent 14c age suggest a deglaciation age for the marguerite bay area of around 12 ka and an average uplift rate of 5 4 mm year 1 on anchorage island for the period between 3 3 and 5 2 ka the weathering rates are extremely slow e g three times slower than reported in norway our data confirm that lichens exert a strong impact on weathering decreasing the schmidt hammer r values on lichenised surfaces by a factor of 3 4 compared to bare rock surfaces the effect of lichens on weathering is mainly due to edaphic conditions and the type of the lichen involved rather the period of exposure

lichenic growth as a factor in the physical deterioration or protection of cappadocian monuments cappadocian monuments that are within tuff have serious deterioration problems understanding the effects of lichens on the tuffs is of utmost importance in this paper interactions between lichen coated surfaces of cappadocian monuments and the rock substratum have been studied thin sections and freshly cut sections were investigated by light and scanning electron microscopy the presence of clay minerals and zeolites as weathering by products produced by alteration and hydrolysis of glass and feldspars was assessed by xrd patterns furthermore some physical properties of the tuff coated by and free of lichens were measured and compared analysis of mineralogical data has shown that the main weathering mechanism can be identified as hydrolysis of some of the rock forming minerals the lichenic coat reduces the presence of water inside the rock thus protecting the rock material from physical decay and disintegration

advances in permafrost and periglacial research in antarctica a review recently the research on permafrost periglacial morphology and processes had a great stimulus especially from the international polar year permafrost areas of continental antarctica with its extreme dry and cold environment can be considered an analog of extraterrestrial landscapes like those on mars but also preserve much paleoclimatic information of this crucial part of the global climatic system on the other hand maritime antarctica is one of the areas of the world currently affected by the greatest air warming and provides a unique opportunity to understand the impacts of climate change on permafrost and its related ecosystems despite the significant recent progress some gaps on permafrost distribution still remain as the network for permafrost and active layer monitoring needs further enlargement and better standardization ground ice its age and stability over time need further investigation as well as the role of living organisms on the weathering processes within the cryotic rocks the landscape evolution of continental antartica could be improved providing potential implications also for a better understanding and modeling of life and landscape evolution of other planets

biogeomorphology past present and future abstract since the 1970s there has been a considerable expansion in biogeomorphological research which considers the complex two way relationships between biological ecological and geomorphological systems over a wide range of spatial and temporal scales advances have been made in theoretical methodological thematic and applied aspects of biogeomorphology a review of key publications and symposia over the period illustrates growth in biogeomorphology with particular advances in quantitative understandings of biogeomorphic interactions in interdisciplinary participation and in theoretical framings theoretical advances have been influenced by the desire to answer four fundamental questions how do ecological and geomorphological systems interact is there a geomorphological signature of life how important is biodiversity to landscape evolution and vice versa how have life and landscape co evolved a review of methodological advances in biogeomorphology confirms the continuing importance of field monitoring and the increasingly tight collaboration between experimental and modelling based research thematically particularly strong progress has been made in disentangling the complex bidirectional biogeomorphic interactions in coastal sedimentary environments and fluvial and riparian systems it is increasingly obvious that variation in ecological traits leads to large differences in biogeomorphic impacts of different species in different circumstances this poses challenges for applications of biogeomorphology to environmental management and conservation seven key topics emerge from this review and provide the basis for a biogeomorphological research agenda to usher in the next 50 yr of progress

ice sheet grounding zone stabilization due to till compaction 1 based on modeling motivated by new gps and radio echo sounding surveys a few kilometers long zone of whillans ice stream west antarctica just inland of the grounding line has higher basal shear stress than the ice farther upstream or the freely slipping ice shelf downstream data from this zone show a few meter high upwarp of the surface overlying a large fold extending through all internal radar layers observed flowband modeling shows that the fold can be generated by decreased basal lubrication beneath the upwarp basal topography alone cannot create this fold physical modeling and available data suggest that low amplitude tidal flexure of the ice shelf extends a few kilometers inland downward flexing of this grounded ice from the rising tide would compact subglacial till resulting in higher basal shear stress this result suggests that important processes influencing grounding line stability are not included in modern whole ice sheet models

methods for measuring rock surface weathering and erosion a critical review studies of rates processes and modes of rock surface and near surface deterioration and also hardening are central to rock weathering and building stone research conservation and management there is a need to measure and monitor weathering at the rock atmosphere interface to facilitate understanding of climatic environmental and lithological controls on the evolution and development of surface weathering features this paper reviews long established and recently developed field and laboratory methods used by geomorphologists to monitor and measure the impact of weathering and erosion on physical and mechanical properties of exposed rock surfaces and their immediate subsurface key advances are highlighted their application to multi scalar understanding and modelling of rock surface weathering in different contexts is discussed and potential future advances to provide new insights into rock weathering durability and materials conservation are identified in highlighting key advantages and disadvantages of a wide range of methods to the broader earth science community the paper aims to contribute to further innovative thinking across disciplines to develop new methods for measuring and monitoring rock weathering