Montane Basin Research Articles

Flood Simulations Using a Sensor Network and Support Vector Machine Model

This study aims to couple the support vector machine (SVM) model with a hydrometeorological wireless sensor network to simulate different types of flood events in a montane basin. The model was tested in the mid-latitude montane basin of Vydra in the Šumava Mountains, Central Europe, featuring complex physiography, high dynamics of hydrometeorological processes, and the occurrence of different types of floods. The basin is equipped with a sensor network operating in headwaters along with the conventional long-term monitoring in the outlet. The model was trained and validated using hydrological observations from 2011 to 2021, and performance was assessed using metrics such as R2, NSE, KGE, and RMSE. The model was run using both hourly and daily timesteps to evaluate the effect of timestep aggregation. Model setup and deployment utilized the KNIME software platform, LibSVM library, and Python packages. Sensitivity analysis was performed to determine the optimal configuration of the SVR model parameters (C, N, and E). Among 125 simulation variants, an optimal parameter configuration was identified that resulted in improved model performance and better fit for peak flows. The sensitivity analysis demonstrated the robustness of the SVR model, as different parameter variations yielded reasonable performances, with NSE values ranging from 0.791 to 0.873 for a complex hydrological year. Simulation results for different flood scenarios showed the reliability of the model in reconstructing different types of floods. The model accurately captured trend fitting, event timing, peaks, and flood volumes without significant errors. Performance was generally higher using a daily timestep, with mean metric values R2 = 0.963 and NSE = 0.880, compared to mean R2 = 0.913 and NSE = 0.820 using an hourly timestep, for all 12 flood scenarios. The very good performance even for complex flood events such as rain-on-snow floods combined with the fast computation makes this a promising approach for applications.

Spatiotemporal patterns of emergence phenology reveal complex species‐specific responses to temperature in aquatic insects

AbstractAimClimate change is broadly affecting phenology, but species‐specific phenological response to temperature is not well understood. In streams, insect emergence has important ecosystem‐level consequences because emergent adults link aquatic and terrestrial food webs. We quantified emergence timing and duration (within‐population synchronicity) of insects among streams along a spatiotemporal gradient of mean water temperature in a montane basin to assess the sensitivity of these phenological traits to heat accumulation from mid‐winter through spring emergence periods.LocationSix headwater streams in the Lookout Creek basin, H.J. Andrews Experimental Forest, Oregon, USA.MethodsWe collected emerging adults of four abundant insect species twice weekly throughout spring for 6 consecutive years. We fit Gaussian models to the empirical temporal distributions to characterize peak emergence timing (mean) and duration (days between 5th and 95th percentiles) for each species/stream/year combination. We then quantified relationships between degree‐day accumulation and phenological response.ResultsOnly one of the four species (a caddisfly) showed a simple response of earlier emergence timing in both warmer streams and years. One stonefly had lengthy emergence periods resulting in substantial phenological overlap between warmer and cooler streams/years. Interestingly, two species (a mayfly and a stonefly) responded strongly to temporal (interannual) temperature differences but minimally to spatial differences, indicating that emergence was nearly synchronous among streams, within years. These two species had among‐stream differences approaching 500 degree‐days from mid‐winter to peak emergence. Conversely, duration of emergence was more strongly associated with spatial than temporal differences, with longer duration in lower‐elevation (warmer) streams.Main conclusionsEmergence phenology has species‐specific responses to temperature likely driven by complex cues for diapause or quiescence periods during preceding life cycle stages. We hypothesize a trade‐off between complex phenological response that synchronizes emergence among heterogeneous sites and other traits such as adult longevity and dispersal capacity.

Which Aspects of Hydrological Regime in Mid-Latitude Montane Basins Are Affected by Climate Change?

This study analyzed the long-term alterations in runoff regime, seasonality and variability in headwater montane basins in Central Europe in response to the manifestations of climate change. We tested the common hypotheses on climate change effects on surface runoff dynamics in the Central Europe region, assuming that (i) recent climate warming will result in shifts in the seasonality of runoff, (ii) the runoff balance will remain without significant changes and (iii) that higher variability in runoff can be expected. The analyses were done on eight montane catchments in four mid-latitude mountain ranges in Central Europe, based on the uninterrupted time series of daily discharge observations from 1952 to 2018. We used 33 indicators of hydrologic alteration (IHA), 34 indicators of environmental flow components, the baseflow index, the calculation of surplus and deficit volumes and the frequency of peak and low flows. Homogeneity testing using Buishand, Pettitt and SNHT tests was applied to test the response of the hydrological alteration indicators to climate warming. We have proved the significant shifts in runoff seasonality, coinciding with the timing of the air temperature rise, marked by earlier snowmelt, followed by a decline in spring flows and a prolonged period of low flows. There was detected a rise in the baseflow index across the mountain ranges. Unlike the common hypotheses, the expected rise of runoff variability and frequency of peak flows was not demonstrated. However, we have identified a significant change of the flood hydrographs, tending to steeper shape with shorter recessing limbs as a sign of rising inner dynamics of flood events in montane catchments.

Eo-Oligocene Oil Shales of the Talawi, Lubuktaruk, and Kiliranjao Areas, West Sumatra: Are they potential source rocks?

DOI:10.17014/ijog.v1i3.198To anticipate the increasing energy demand, additional data and information covering unconventional fossil fuels such as oil shale must be acquired to promote the usage of alternative energy sources to crude oil. The Talawi and Lubuktaruk regions situated within intra-montane Ombilin Basin, and the Kiliranjao assumed to be a small intra montane basin are occupied by Eo-Oligocene sediments of Sangkarewang and Kiliran Formations, respectively. Field activity, geochemical screening techniques, and organic petrographic analysis, supported by SEM mode, are methods used. Most of the oil shale sequence is typically of an organically rich-succession comprising predominantly well-bedded, laminated and fissile, brownish to dark grey organic-rich shale and mudstone rocks. The exinite macerals within oil shale comprise mainly Pediastrum-lamalginite with minor cutinite, resinite, liptodetrinite, sporinite, bituminite, and rare Botryococcus-telalginite. Therefore; the oil shale deposits can be described as “lamosites”. Minor vitrinite maceral is also recognized. TOC analysis on selected shale samples corresponds to a fair up to excellent category of source rock characterization. The hydrogen index (HI) for all samples shows a range of values from 207 - 864, and pyrolysis yield (PY) ranges from 2.67 to 79.72 mg HC/g rock. The kerogen is suggested to be of mixed Type II and Type I autochthonous materials such as alginite, with minor allochthonous substances. Oil samples collected appear to be positioned within more oil prone rather than gas prone. Thermal maturity of the oil shales gained from Tmax value and production index (PI) tends to show immature to marginally/early mature stage. A consistency in the thermal maturity level results by using both Tmax and vitrinite reflectance value is recognized. On the basis of SEM analysis, the oil shale has undergone a late eodiagenetic process. Thereby, overall, vitrinite reflectance agreeing with Tmax rates, are also consistent with the PI (production index) values and SEM result. By evaluating all the results of geochemical and organic petrological analyses conducted on shale lithologies (shale and mudstone), it can be concluded that the oil shales in those areas have a favourable potential for generation of shale oil or gas to be included as alternative energy resources in the future.

Taxonomic notes on the New Zealand flora: a new species of Centrolepis for New Zealand, Centrolepis glabra (F.Muell. ex Sonder) Hieron., and the taxonomic status of Centrolepis minima Kirk (Centrolepidaceae)

A new indigenous species is recorded for the New Zealand flora, Centrolepis glabra, found in lakes and kettlehole tarns of the inner montane basins of the South Island. Centrolepis glabra has previously been known only from Australia. A description of C. glabra based on New Zealand material and notes on habitat and distribution are provided. The name, C. minima, has been consistently misapplied to specimens referable to C. glabra, obscuring its presence in New Zealand. Centrolepis minima Kirk is determined as conspecific with C. pallida (Hook.f.) Cheeseman. The name C. pallida, first published as Gaimardia pallida Hook.f. (1853), has priority over C. minima Kirk (1891).

Subsurface architecture of the Boulder Creek Critical Zone Observatory from electrical resistivity tomography

ABSTRACTThe architecture of the critical zone includes the distribution, thickness, and contacts of various types of slope deposits and weathering products such as saprolite and weathered bedrock resting on solid bedrock. A quantitative analysis of architecture is necessary for many model‐driven approaches used by pedologic, geomorphic, hydrologic or biologic studies. We have used electrical resistivity tomography, a well‐established geophysical technique causing minimum surficial disturbance, to portray the subsurface electrical resistivity differences at three study sites (Green Lakes Valley; Gordon Gulch; Betasso) at the Boulder Creek Critical Zone Observatory (BcCZO). Possible limitations of the technique are discussed. Interpretation of the specific resistivity values using natural outcrops, pits, roadcuts and drilling data as ground truth information allows us to image the critical zone architecture of each site. Green Lakes Valley (3700 MASL), a glacially eroded alpine basin, shows a rather simple, split configuration with coarse blockfields and sediments, partly containing permafrost above bedrock. The critical zone in Gordon Gulch (2650 MASL), a montane basin with rolling hills, and Betasso (1925 MASL), a lower montane basin with v‐shaped valleys, is more variable due to a complex Quaternary geomorphic history. Boundaries between overlying stratified slope deposits and saprolite were identified at mean depths of 3.0 ± 2.2 m and 4.1 ± 3.6 m in the respective sites. The boundary between saprolite and weathered bedrock is deeper in Betasso at 5.8 ± 3.7 m, compared with 4.3 ± 3.0 m in Gordon Gulch. In general, the data are consistent with results from seismic studies, but electrical resistivity tomography documents a 0.5–1.5 m shallower critical zone above the weathered bedrock on average. Additionally, we document high lateral variability, which results from the weathering and sedimentation history and seems to be a consistent aspect of critical zone architecture within the BcCZO. Copyright © 2013 John Wiley & Sons, Ltd.

Preliminary evaluation of the runoff processes in a remote montane cloud forest basin using Mixing Model Analysis and Mean Transit Time

AbstractIn this study, the Mean Transit Time and Mixing Model Analysis methods are combined to unravel the runoff generation process of the San Francisco River basin (73.5 km2) situated on the Amazonian side of the Cordillera Real in the southernmost Andes of Ecuador. The montane basin is covered with cloud forest, sub‐páramo, pasture and ferns. Nested sampling was applied for the collection of streamwater samples and discharge measurements in the main tributaries and outlet of the basin, and for the collection of soil and rock water samples. Weekly to biweekly water grab samples were taken at all stations in the period April 2007–November 2008. Hydrometric data, Mean Transit Time and Mixing Model Analysis allowed preliminary evaluation of the processes controlling the runoff in the San Francisco River basin. Results suggest that flow during dry conditions mainly consists of lateral flow through the C‐horizon and cracks in the top weathered bedrock layer, and that all subcatchments have an important contribution of this deep water to runoff, no matter whether pristine or deforested. During normal to low precipitation intensities, when antecedent soil moisture conditions favour water infiltration, vertical flow paths to deeper soil horizons with subsequent lateral subsurface flow contribute most to streamflow. Under wet conditions in forested catchments, streamflow is controlled by near surface lateral flow through the organic horizon. Exceptionally, saturation excess overland flow occurs. By absence of the litter layer in pasture, streamflow under wet conditions originates from the A horizon, and overland flow. Copyright © 2011 John Wiley & Sons, Ltd.

Are transit times useful process‐based tools for flow prediction and classification in ungauged basins in montane regions?

AbstractTransit times are being increasingly explored as process‐based tools for conceptualizing hydrological function at a range of scales. Despite this, little effort has been made to relate transit times to conventional hydrometric flow statistics. Rather, the identification of the appropriate transit time distribution (TTD) for a hydrological system and the derivation of metrics such as the mean transit time (MTT) have required quantitative assessment of input–output relationships for conservative tracers using lumped parameter models. This has allowed the main landscape controls to be identified and has facilitated the prediction of MTTs in ungauged basins in particular geomorphic provinces, though relationships with streamflow measures have been unexamined. We used estimated MTTs (with uncertainty) for 16 experimental catchments (0·5–690 km2in area) with contrasting geologic, topographic, pedologic and climatic characteristics in Scotland. The MTT was highly variable ranging from 60 days toca> 1500 days, reflecting differences in catchment soil cover, geomorphic properties and precipitation. The MTT was closely correlated with key hydrometric design statistics such as the mean annual flood (MAF) and percentiles of high (Q5) and low (Q95) flows. Analysis of MTT estimates, in conjunction with geographic information system (GIS)‐based assessment of landscape controls, showed that MTT could be predicted to within 30% for ungauged basins from catchment soil cover and drainage density. Furthermore, hydrometric design statistics for ungauged basins could also be forecast from MTT predictions with median relative errors of 14, 11 and 28% for the MAF, Q5and Q95respectively. We suggest that MTTs—predicted from mapped landscape characteristics—can be useful diagnostic metrics for ungauged montane basins, as well as a useful similarity index for process‐based catchment classification. This is important as montane headwaters are often critical, but data‐poor environments influencing the quantity, quality and ecology of downstream flows. Copyright © 2010 John Wiley & Sons, Ltd.

Effects of Urban Development on Ant Communities: Implications for Ecosystem Services and Management

Research that connects the effects of urbanization on biodiversity and ecosystem services is lacking. Ants perform multifarious ecological functions that stabilize ecosystems and contribute to a number of ecosystem services. We studied responses of ant communities to urbanization in the Lake Tahoe basin by sampling sites along a gradient of urban land development. We sampled ant communities, measured vegetation characteristics, quantified human activities, and evaluated ant-community responses by grouping ants into service-providing units (SPUs), defined as a group of organisms and their populations that perform specific ecosystem services, to provide an understanding of urbanization impacts on biodiversity and their delivery of ecosystem services. Species richness and abundance peaked at intermediate levels of urban development, as did the richness of 3 types of ant SPUs (aerators, decomposers, and compilers). With increasing land development aerator and decomposer ants significantly declined in abundance, whereas compiler ants significantly increased in abundance. Competing models demonstrated that precipitation was frequently among the strongest influences on ant community structure; however, urban development and human activities also had a strong, negative influence on ants, appearing in most models with DeltaAIC(c) < 2 for species richness and abundance patterns of SPUs and generalists. Response diversity was observed within SPUs, which suggests that the corresponding ecosystem services were maintained until development reached 30-40%. Our data provide evidence that ecosystem functions, such as water infiltration and soil productivity, may be diminished at sites subject to greater levels of urbanization and that conserving ant communities and the ecosystem services they provide could be an important target in land-use planning and conservation efforts.

Environmental changes in the Zirahuén Basin, Michoacán, Mexico, during the last 1000 years

Lago de Zirahuen (19° 26′ N, 101° 44′ W) lies within a montane basin in highland Michoacan, Mexico at 2075 m a.s.l. The lake basin has high recreational value and is promoted as a tourist attraction. Four short (<1 m), sediment–water interface cores were used to investigate Late Holocene environmental change. The cores span approximately the last 1000 years, based on 210Pb dating, AMS 14C dating and tephrochronology. Cesium-137, Americium-241 and tephra layers from Volcan Paricutin (AD 1943–1952) and Volcan Jorullo (AD 1759–1774) provide independent age markers. Cores were analysed for diatoms, magnetic susceptibility and heavy metals (iron, lead, manganese, copper and zinc). Drier climate around 1000 years BP is tentatively inferred from the diatom assemblage and is concordant with other regional records. Increased soil erosion between ca. AD 1100 and AD 1550 may be associated with Pre-Hispanic settlement in the basin, but there is no archaeological evidence to support this. A period of catchment stability occurred during the early Colonial Period, ca. AD 1550–1750. The dramatic decline in the indigenous population following the Spanish Conquest in 1521 may have promoted vegetation recovery on the basin slopes. After the mid-18th century, a significant change in diatom species composition is observed along with an increase in soil erosion, as inferred from the magnetic susceptibility profile. Concentrations of copper and lead also increased. These changes are associated with the establishment of a copper smelting industry in the basin and increased Colonial agricultural development. Recently, tourist developments and commercial agriculture have impacted on the basin. The diatom flora has changed dramatically in the last 20 years, apparently in response to the onset of cultural eutrophication. The palaeoenvironmental evidence suggests that the lake is responding rapidly to land use intensification in the basin, which may have implications for future developments.

Throughfall, stemflow, and canopy interception loss fluxes in a semi-arid Sierra Madre Oriental matorral community

Gross precipitation, throughfall, and stemflow were measured in a representative matorral subinerme study plot within a small montane basin of the Sierra Madre Oriental throughout three wet season periods. Data analysis suggests that of the 394.8 mm of cumulative gross precipitation generated by 25 sampled events, throughfall, stemflow, and canopy interception loss fluxes were 329.0±7.7 mm (83.3±1.9%), 33.5±7.6 mm (8.5±1.9%), and 32.3±10.8 mm (8.2±2.7%), respectively. Stemflow from four woody plant stems was found to be moderately correlated ( r=0.54) with the product of gross precipitation multiplied by stem basal area, while the season-long Herwitz (Earth Surf. Process. Landforms 11 (1986) 401) funneling ratios for these stems averaged 21.1. The relatively large concentrations of water delivered to the bases of these plants suggest that stemflow generation may be a means of surviving drought conditions. The importance of and possible factors influencing during-event evaporation from the saturated matorral subinerme canopy, as well as recommendations for future canopy water flux studies in this plant community, are discussed.

Molecular Analysis of Genetic Variation among Large- and Small-Bodied Sage Grouse Using Mitochondrial Control-Region Sequences

Sage Grouse (Centrocercus urophasianus) are lek breeders whose numbers are in serious decline in some areas owing to fragmentation and loss of shrubsteppe habitat (Aldrich 1963, Johnsgard 1983, Braun 1993, 1995). Based on plumage differences (Aldrich and Duvall 1955), they have been divided taxonomically into two subspecies: C. u. urophasianus (Eastern Sage Grouse) and C. u. phaios (Western Sage Grouse), although the validity of these subspecies designations has been questioned (Johnsgard 1983). Differences in size, filoplume length, tail banding, strut display, and vocalizations (Barber 1991, Hupp and Braun 1991, Young 1994, Young et al. 1994, Braun and Young 1995) led Braun and Young (1995) to propose that the large-bodied and forms of Sage Grouse constitute two distinct species. The largest population of the small-bodied Sage Grouse is in Gunnison County, Colorado (2,400 to 3,000 individuals; C. E. Braun unpubl. data), in a montane basin surrounded by tall mountains (3,100 to 4,200 m) to the north and east (Hupp and Braun 1989) and the Great Basin desert to the west (Young et al. 1994). Sage Grouse that were extirpated from New Mexico, Oklahoma, Arizona, and at least nine other counties in southwestern Colorado probably belonged to this small-bodied taxon as well (Young et al. 1994). The main goals of this study were to ascertain whether genetic differences exist between the largeand small-bodied forms of Sage Grouse and to estimate a crude time frame involved in the morphological and behavioral differences between the forms. We surveyed the rapidly evolving control region of the mitochondrial DNA (mtDNA) genome because it is likely to be informative for resolving differences

The glacilacustrine sedimentary environment of Bowser Lake in the northern Coast Mountains of British Columbia, Canada

Bowser Lake, a fiord lake in the northern Coast Mountains of British Columbia, contains a thick Holocene fill consisting mainly of silt and clay varves. These sediments were carried into the lake by proglacial Bowser River which drains a high-energy, heavily glacierized basin. Sedimentation in the lake is controlled by seasonal snow and ice melt, by autumn rainstorms, and by rare, but very large jokulhlaups from glacier-dammed lakes in the upper Bowser River basin which complicate environmental inferences from the sedimentary record. Sediment is dispersed through the deep western part of the lake by energetic turbidity currents. The turbidity currents apparently do not overtop a sill that separates the western basin from much shallower areas to the east. Large amounts of silt and clay are deposited from suspension in the eastern part of the lake, but sediment accumulation rates there are much lower than to the west. Several strong acoustic reflectors punctuate the varved fill in the western basin; these may be thick or relatively coarse beds deposited during jokulhlaups or exceptionally large storms. The contemporary sediment yield to Bowser Lake, estimated from sediments in the lake, is about 360 t km-2a-1. This is a relatively high value, but it is less than yields insome other, similar montane basins with extensive snow and ice cover.The most likely explanation for the difference is that large amounts of sediment have been, and continue to be, stored on the Bowser delta andin small proglacial lakes.

Phenotypic divergence of secondary sexual traits among sage grouse, Centrocercus urophasianus, populations

Abstract. Sage grouse, Centrocercus urophasianus, in an isolated montane basin near Gunnison, Colorado differ in several morphological and behavioural traits from conspecifics studied in other areas of the species' range. Both sexes in Gunnison are smaller than sage grouse elsewhere, and males possess differences in feather morphology as well. The mating behaviour of male sage grouse in three populations was examined to determine whether male strut displays of Gunnison sage grouse were behaviourally distinct. Behavioural analyses revealed Gunnison males perform strut displays at a slower rate than males in the two other sage grouse populations sampled. In addition, Gunnison males' strut displays contain unique visual and acoustical aspects. The most distinguishing attributes of Gunnison sage grouse were male secondary sexual characteristics including traits that correlate with mating success in other populations. Thus, phenotypic differences observed in the Gunnison population represent a divergence in expression of traits that are likely to be influenced by sexual selection. Recent models of speciation suggest that species characterized by intense sexual selection, such as those with lek mating systems, have the potential for rapid inter-populational divergence in male traits and female preferences leading to speciation.

CLASSIFICATION OF ALLUVIAL FANS IN JAPAN BY TOPOGRAPHICAL AND GEOLOGICAL DATA OF DRAINAGE BASINS

The ratios of drainage basins with alluvial fans to all basins show two reliable peaks around 100 km2 and 500 km2 in the Japanese Islands (Fig. 1). The conditions of the alluvial fan formation were analyzed by interpretation of the peaks. The bedrock lithology of drainage basins favourable for the formation of fans is plutonic rocks, tuffs, agglomerates, and metamorphic rocks (Table 2) . In such basins debris flows are considered to have frequently occurred in Japan. The drainage basins smaller than 250 km2 in area with alluvial fans are dominantly occupied by these rocks (Fig. 4). Furthermore, it has been pointed out that drainage patterns of basins smaller than 200 km2 in area are simple in Japan (Fig. 6), and that such basins provide the large specific peak discharge (Fig. 5). By taking all these factors into consideration, it can be stated that the detritus deposited by the debris flow on the river bed in the mountain is transported to the valley mouth at a stretch by the flood flow, and that alluvial fans are composed of such detritus. Paticularly, in the drainage basins around 100 km2 in area, the markedly high ratio of drainage basins with fans to all basins is considered to be attributed to the frequent occurrence of the flood. In the drainage basins larger than 200 km2 in area, the specific peak discharge is not high due to the complicated drainage patterns, but the total discharge is high enough to bring about the flood frequently. The wider the drainage basins are, the weaker the influence of the lithology on the formation of the alluvial fan (Table 3), It may be inferred that the bedload in the mountain are transported to the valley mouth by a number of floods and that the formation of an alluvial fan is a result of deposition by a stream which has swinged its channel to and fro over the accumulation material. This idea is supported by the fact that alluvial fans have been extensively formed in actively uplifted areas, i.e. Central Japan (Fig. 7), where sediments yield is very abundant. As the drainage basins become wider, the discharge and occurrece of floods increase. However, the ratios of basins with alluvial fans to those larger than 500 km2 in area decrease with the increase of area. This suggests that the coarser sediments cannot be transported to mountain fronts by the rivers due to gentle gradients and are mostly deposited in montane basins (Table 4). In the drainage basins around 200 km2 in area the debris on the river bed is considered to be rarely reansported to the valley mouth at a stretch by the flood flow. After the transpotation has happened, the next flood flow appears to erode the debris deposited at the mountain front, because of a relatively small quantity of bedload in spite of large discharge. Consequently, it is difficult for the drainage basins around 200 km2 in area to form alluvial fans except the smaller ones (Fig. 2).