Interior Drainage Research Articles

Multi-Scale Variation in Surface Water Area in the Yellow River Basin (1991–2023) Based on Suspended Particulate Matter Concentration and Water Indexes

Surface water is a crucial part of terrestrial ecosystems and is crucial to maintaining ecosystem health, ensuring social stability, and promoting high-quality regional economic development. The surface water in the Yellow River Basin (YRB) has a high sediment content and spatially heterogeneous sediment distribution, presenting a significant challenge for surface water extraction. In this study, we first analyze the applicability of nine water indexes in the YRB by using the Landsat series images (Landsat 5, 7, 8) and then examine the correlation between the accuracy of the water indexes and suspended particulate matter (SPM) concentrations. On this basis, we propose a surface water extraction method considering the SPM concentrations (SWE-CSPM). Finally, we examine the dynamic variations in the surface water in the YRB at four scales: the global scale, the secondary water resource zoning scale, the provincial scale, and the typical water scale. The results indicate that (1) among the nine water indexes, the MBWI has the highest water extraction accuracy, followed by the AWEInsh and WI2021, while the NDWI has the lowest. (2) Compared with the nine water indexes and the multi-index water extraction rule method (MIWER), the SWE-CSPM can effectively reduce the commission errors of surface water extraction, and the water extraction accuracy is the highest (overall accuracy 95.44%, kappa coefficient 90.62%). (3) At the global scale, the maximum water area of the YRB shows a decreasing trend, but the change amount is small. The permanent water area shows an uptrend, whereas the seasonal water area shows a downtrend year by year. The reason may be that the increase in surface runoff and the construction of reservoir projects have led to the transformation of some seasonal water into permanent water. (4) At the secondary water resource zoning scale, the permanent water area of other secondary water resource zonings shows an increasing trend in different degrees, except for the Interior Drainage Area. (5) At the provincial scale, the permanent water area of all provinces shows an uptrend, while the seasonal water areas show a fluctuating downtrend. The maximum water area of Shandong, Inner Mongolia Autonomous Region, and Qinghai increases slowly, while the other provinces show a decreasing trend. (6) At the typical water scale, there are significant differences in the water area variation process in Zhaling Lake, Eling Lake, Wuliangsuhai, Hongjiannao, and Dongping Lake, but the permanent water area and maximum water area of these waters have increased over the past decade. This study offers significant technical support for the dynamic monitoring of surface water and helps to deeply understand the spatiotemporal variations in surface water in the YRB.

Can the Accuracy of Fine-Resolution Precipitation Products Be Assessed from the Surrounding Water Balance and Drought Chain (WBDC) in the Qinghai–Tibetan Plateau?

The Qinghai–Tibetan Plateau (QTP), which has a unique and severe environment, suffers from the absence of rainfall gauges in western arid land. Using different precipitation products in this region would easily lead to contradictory results. To evaluate nine fine-resolution precipitation products in the QTP, we propose a “down to top” methodology, based on water balance and drought chain, by forecasting two accuracy assessment indices—multi-year precipitation bias and precipitation correlation. We assessed the biases of all products in the Jinsha–Yalong, Yellow, Heihe, Yangtze, Yarlung Zangbo catchments and interior drainage areas. And we assessed gauge-based correlation of precipitation products, based on the correlations between precipitation product-based effective drought index (EDI), Soil Moisture Active Passive (SMAP)-based soil moisture anomaly, and the moderate-resolution imaging spectroradiometer (MODIS)-based normalized difference vegetation index (NDVI) anomaly (R = 0.712, R = 0.36, and R = 0.785, respectively) for cross-sectional rainfall observations on the Tibetan Plateau in 2018. The results showed that ERA5-Land and IMERG merged precipitation dataset (EIMD) can efficiently close the water budget at the catchment scale. Moreover, the EIMD-based EDI exhibited the best performance in correlation with both the SMAP-based soil moisture anomaly and MODIS-based NDVI anomaly for the three main herbaceous species areas—Kobresia pygmaea meadow, Stipa purpurea steppe, and Carex moorcroftii steppe. Overall, we find that EIMD is the most accurate among the nine products. The annual average precipitation (2001–2018) was determined to be 568.16 mm in the QTP. Our assessment methodology has a remote sensing basis with low cost and can be used for other arid lands in the future.

A monthly distributed water and salt balance model in irrigated and non-irrigated lands of arid irrigation district with shallow groundwater table

Water scarcity and soil salinization are two major problems threatening the sustainability of irrigation districts in arid regions with shallow groundwater table. To study water and salt balances in arid irrigation districts, we developed a monthly distributed water and salt balance model for arid irrigation district (DAHMID-S) with shallow groundwater table by integrating models of major hydrological processes and the associated salt transport processes, including irrigation, evapotranspiration, soil water and groundwater and salt balances, drainage of water and salt through ditches, and interior drainage of water and associated dry drainage of salt between irrigated and non-irrigated lands. The model was successfully applied to the Hetao Irrigation District (HID), the largest irrigation district in the arid region of China. Results indicate that evapotranspiration is the dominant water consumption component in the HID and accounts for about 95% of the total irrigation and precipitation, while drainage through ditches accounts for 10.5% of the total irrigation. Only 49.4% of the introduced salt is discharged from the HID through drainage ditches. Consequently, most parts of the HID are in the state of salt accumulation except the northern Wulate sub-irrigation district, and the problem of salt accumulation is more serious in the western and southern HID under more favorable conditions of water use. Dry drainage plays a crucial role in salt balance of both irrigated and non-irrigated lands, which results in desalinization in most irrigated lands while salt accumulation in non-irrigated lands. Appropriate measures should be taken to solve water and salt-related problems to improve the sustainability of the HID. In the western HID, irrigation water diversion should be decreased, and the drainage system should be further improved to decrease the salt accumulation to a lower level. Meanwhile, the irrigation water diversion can be increased in the southeastern HID by planting more corn and wheat. Besides, irrigation management should be improved to reduce the surface water return flow to increase the groundwater drainage capacity, especially in the southwestern HID.

A monthly distributed agro-hydrological model for irrigation district in arid region with shallow groundwater table

Agro-hydrological processes in arid irrigation districts mainly include precipitation, water diversion, irrigation, drainage, evapotranspiration (ET), and soil water and groundwater flow, which interact with each other and are controlled by complex natural and anthropogenic drivers. To better understand the agro-hydrological processes in arid irrigation districts with shallow groundwater table, we developed a novel monthly distributed agro-hydrological model for irrigation districts (DAHMID) based on the concepts of canal command area (CCA) and sub-drainage command area (SDCA). The DAHMID model is driven by meteorology, irrigation, and evapotranspiration (ET) estimated by remote sensing-based ET model, and considers soil water and groundwater balances in both irrigated and non-irrigated lands and interior drainage between them. The model was applied to Hetao Irrigation District (HID), the largest irrigation district in arid region of China with a total irrigated area of 0.68 million ha. The DAHMID model was calibrated with groundwater table depth measurements in 13 CCAs of HID from 2008 to 2010, and validated from 2012 to 2013. Results depicted that the root mean square errors (RMSEs), normalized RMSEs (NRMSEs), Nash-Sutcliffe efficiency coefficients (NSEs), and coefficients of determination (r2) of groundwater table depth in both irrigated and non-irrigated lands for all CCAs were in the ranges of 0.19–0.34 m, 0.10–0.25, 0.30–0.82, and 0.68–0.91, respectively. The simulation results from 2008 to 2014 indicated that interior drainage from irrigated land to non-irrigated land is an important approach of drainage in HID, which is about 14.3% of total irrigation water diversion and 34.9% more than the drainage through ditches. The interior drainage process is basically similar to irrigation and ditch drainage processes, all reaching their peaks in May and October. ET is the major water consumption in HID, which is about 95% of total irrigation water diversion and precipitation in average. The net capillary rise of irrigated land is significantly less than that of non-irrigated land due to the impact of irrigation infiltration. The DAHMID model has less parameters and requires less inputs, and can be better applied to continuous simulation of agro-hydrological processes in irrigation districts in medium and long periods with satisfactory simulation accuracy.

Fast Pliocene integration of the Central Anatolian Plateau drainage: Evidence, processes, and driving forces

Abstract Continental sedimentation was widespread across the Central Anatolian Plateau in Miocene–Pliocene time, during the early stages of plateau uplift. Today, however, most sediment produced on the plateau is dispersed by a well-integrated drainage and released into surrounding marine depocenters. Residual long-term (106–107 yr) sediment storage on the plateau is now restricted to a few closed catchments. Lacustrine sedimentation was widespread in the Miocene–Pliocene depocenters. Today, it is also restricted to the residual closed catchments. The present-day association of closed catchments, long-term sediment storage, and lacustrine sedimentation suggests that the Miocene–Pliocene sedimentation also occurred in closed catchments. The termination of sedimentation across the plateau would therefore mark the opening of these closed catchments, their integration, and the formation of the present-day drainage. By combining newly dated volcanic markers with previously dated sedimentary sequences, we show that this drainage integration occurred remarkably rapidly, within 1.5 m.y., at the turn of the Pliocene. The evolution of stream incision documented by these markers and newly obtained 10Be erosion rates allow us to discriminate the respective contributions of three potential processes to drainage integration, namely, the capture of closed catchments by rivers draining the outer slopes of the plateau, the overflow of closed lakes, and the avulsion of closed catchments. Along the southern plateau margin, rivers draining the southern slope of the Central Anatolian Plateau expanded into the plateau interior; however, only a small amount of drainage integration was achieved by this process. Instead, avulsion and/or overflow between closed catchments achieved most of the integration, and these top-down processes left a distinctive sedimentary signal in the form of terminal lacustrine limestone sequences. In the absence of substantial regional climate wetting during the early Pliocene, we propose that two major tectonic events triggered drainage integration, separately or in tandem: the uplift of the Central Anatolian Plateau and the tectonic completion of the Anatolian microplate. Higher surface uplift of the eastern Central Anatolian Plateau relative to the western Central Anatolian Plateau promoted more positive water balances in the eastern catchments, higher water discharge, and larger sediment fluxes. Overflow/avulsion in some of the eastern catchments triggered a chain of avulsions and/or overflows, sparking sweeping integration across the plateau. Around 5 Ma, the inception of the full escape of the Anatolian microplate led to the disruption of the plateau surface by normal and strike-slip faults. Fault scarps partitioned large catchments fed by widely averaged sediment and water influxes into smaller catchments with more contrasted water balances and sediment fluxes. The evolution of the Central Anatolian Plateau shows that top-down processes of integration can outcompete erosion of outer plateau slopes to reintegrate plateau interior drainages, and this is overlooked in current models, in which drainage evolution is dominated by bottom-up integration. Top-down integration has the advantage that it can be driven by more subtle changes in climatic and tectonic boundary conditions than bottom-up integration.

A high-resolution global runoff estimate based on GIS and an empirical runoff coefficient

Abstract This paper reviews 110 years of global runoff estimation. By employing the method of ordinary least square regression on a sample region's runoff coefficient, an empirical formula of a runoff coefficient is calculated for China. Based on this empirical formula applied with a high-resolution grid of precipitation, runoff is calculated resulting in an equally high-resolution map of global runoff using a geographic information system (GIS). The main results are (1) the global total runoff volume is 47,884 km3, (2) the average runoff depth is 359 mm, (3) the interior drainage region's runoff volume is 1,663 km3, and (4) the average runoff depth is 58.4 mm. The results are compared with the results of the existing literature on global runoff. This study emphasizes the importance of runoff and groundwater recharge in arid and semi-arid regions where the estimation value of runoff depth is significantly increased.

Use of Topographic Map Evidence From Drainage Divides Surrounding Wyoming’s Great Divide Basin to Compare Two Fundamentally Different Regional Geomorphology Paradigms

Divide crossings (or low points or gaps) notched into the North American east-west continental divide segments completely encircling Wyoming’s Great Divide Basin interior drainage region (as observed on detailed topographic maps) are used to compare the commonly accepted regional geomorphology paradigm with a fundamentally different and new regional geomorphology paradigm. Paradigms are sets of rules governing how a scientific discipline conducts its research and are judged on their ability to explain observed evidence. Published literature is used to contrast an accepted paradigm interpretation that east-oriented drainage previously flowed across what is now the Great Divide Basin with the new paradigm basic requirement that mountain range and continental divide uplift occurred while immense south-oriented floods flowed across them. Numerous divide crossings are notched into the continental divide segments now completely encircling the relatively flat-floored Great Divide Basin interior drainage area and divide crossings observed along each of the Great Divide Basin’s north, east, south, and west margins are described and interpreted first from the accepted paradigm perspective (using published literature interpretations to the extent possible) and second from the new paradigm perspective. The published literature does not mention most of the described divide crossings, much less provide explanations for their origins, perhaps because the accepted paradigm cannot satisfactorily explain those origins. In contrast the new paradigm successfully explains most if not all of the described (and observed, but undescribed) divide crossings, although the new paradigm requires a completely different middle and late Cenozoic regional geologic history than what most published regional geology literature describes.

Hurricane Harvey and Greater Houston households: comparing pre-event preparedness with post-event health effects, event exposures, and recovery.

Most disaster studies rely on convenience sampling and 'after-only' designs to assess impacts. This paper, focusing on Hurricane Harvey (2017) and leveraging a pre-/post-event sample of Greater Houston households (n=71) in the United States, establishes baselines for disaster preparedness and home structure flood hazard mitigation, explores household-level ramifications, and examines how preparedness and mitigation relate to health effects, event exposures, and recovery. Between 70 and 80 per cent of participants instituted preparedness measures. Mitigation actions varied: six per cent had interior drainage systems and 83 per cent had elevated indoor heating/cooling components. Sixty per cent reported home damage. One-half highlighted allergies and two-thirds indicated some level of post-traumatic stress (PTS). Three-quarters worried about family members/friends. The results of generalised linear models revealed that greater pre- event mitigation was associated with fewer physical health problems and adverse experiences, lower PTS, and faster recovery. The study design exposed the broad benefits of home structure flood hazard mitigation for households after Harvey.

Assessing the diversity of Western North American Juga (Semisulcospiridae, Gastropoda)

Juga is a genus of freshwater gastropods distributed in Pacific and Interior drainages of the Pacific Northwest from central California to northern Washington. The current classification has relied heavily on features of the shell, which vary within and across drainages, and often intergrade without sharp distinctions between species. The only previous molecular analysis included limited population sampling, which did not allow robust assessment of intra- versus interspecific levels of genetic diversity, and concluded almost every sampled population to be a distinct OTU. We assembled a multilocus mitochondrial (COI, 16S) and nuclear gene (ITS1) dataset for ∼100 populations collected across the range of the genus. We generated primary species hypotheses using ABGD with best-fit model-corrected distances and further explored our data, both individual gene partitions and concatenated datasets, using a diversity of phylogenetic and species delimitation methods (Bayesian inference, maximum likelihood estimation, StarBEAST2, bGMYC, bPTP, BP&P). Our secondary species delimitation hypotheses, based primarily on the criterion of reciprocal monophyly, and informed by a combination of geography and morphology, support the interpretation that Juga comprises a mixture of geographically widespread species and narrow range endemics. As might be expected in taxa with low vagility and poor dispersal capacities, analysis of molecular variance (AMOVA) revealed highly structured populations with up to 80% of the observed genetic variance explained by variation between populations. Analyses with bGMYC, bPTP, and BP&P appeared sensitive to this genetic structure and returned highly dissected species hypotheses that are likely oversplit. The species diversity of Juga is concluded to be lower than presently recognized, and the systematics to require extensive revision. Features of the teleoconch considered significant in species-level and subgeneric classification were found to be variable within some species, sometimes at a single site. Of a number of potentially new species identified in non-peer reviewed reports and field guides, only one was supported as a distinct OTU.

Glacier changes on the Tibetan Plateau derived from Landsat imagery: mid-1970s – 2000–13

ABSTRACTGlacier area changes on the Tibetan Plateau were studied in different drainage basins based on Landsat satellite images from three epochs: 263 in the mid-1970s, 150 in 1999–2002 and 148 in 2013/14. Three mosaics (M1976, M2001 and M2013) with minimal cloud and snow cover were constructed, and the uncertainty due to each epoch having a finite span was accounted for. Glacier outlines (TPG1976, TPG2001 and TPG2013) were digitized manually with guidance from the SRTM DEM v4.1 and Google Earth imagery. To achieve complete multi-temporal coverage in a reasonable time, only debris-free ice was delineated. Area mapping uncertainty was evaluated at three study sites, Mount Qomolangma (Everest), Mount Naimona'Nyi, Mount Geladandong, where the largest differences between present and earlier measurements were within ~±4%. Area differences with previous inventories ranged from −19.6% (TPG1976 minus the first Chinese Glacier Inventory) to −3.6% and −1.1% (TPG2013 and TPG2001, respectively minus the second Chinese Glacier Inventory), while the difference TPG2001 minus the GAMDAM Glacier Inventory was +10.4%. Glacier area on the plateau decreased from 44 366 ± 2827 km2(1.7% of the study area) in the 1970s to 42 210 ± 1621 km2in 2001 and 41 137 ± 1616 km2in 2013. Shrinkage was faster in external drainage basins of the southeast than in the interior basins of the northwest, from a maximum of −0.43% a−1(−1.60% a−1during 1994–2013) in the Mekong catchment down to a minimum of −0.12% a−1in the Tarim interior drainage.

Landform assemblage produced by the Biscoe Trough ice stream, northern Antarctic Peninsula

The continental shelf off the Biscoe Archipelago has one of the largest cross-shelf troughs on the Pacific margin of the North Antarctic Peninsula (NAP), the Biscoe Trough (Fig. 1a, b). Grooved and streamlined bedrock, drumlins, mega-scale glacial lineations (MSGLs) and grounding-zone wedges (GZWs) define a continuum of landforms over 130 km that provide evidence that ice streams sourced in three different interior drainage basins converged and flowed along the trough during the Last Glacial Maximum (LGM). The Biscoe Trough is important in understanding the configuration of the Antarctic Peninsula Ice Sheet during the LGM (Lavoie et al. 2015) and the onset of the modern Antarctic ice sheet in the Late Pliocene (Rebesco et al. 2006). Fig. 1. ( a ) Location of study area (red box; map from IBCSO v. 1.0). ( b ) Multibeam-bathymetric image of Biscoe Trough collected during RV Hesperides COHIMAR/SEDANO cruise in 2002. Background bathymetry (in grey) from GEBCO\_08. Acquisition system Simrad EM12-S. Frequency 12.5 kHz. Grid-cell size 50 m. Land area from Landsat Image Mosaic of Antarctica, US Geological Survey. PD, Palmer Deep; HIT, Hugo Island Trough. ( c ) Enlarged multibeam image of Biscoe Trough. 100 m contours from GEBCO\_08. ( d ) Schematic diagram of the main geomorphic features of Biscoe Trough. The main trunk of the Biscoe Trough follows an ESE–WNW orientation. Two NE–SW- and SSE–NNW-orientated tributary troughs enter Biscoe Trough from the north and south, respectively (Fig. 1c). The elongate bedforms revealed in multibeam data are initially aligned parallel to these orientations, and show overall convergence towards the shelf edge. The north and south tributary troughs are deepest, with water depths >800 m and 1000 m, respectively (Fig. 1c). The trough boundaries are steep and straight, with a relief of 600 m with respect to the <200 m deep steep-sided banks. A third area of overdeepening, with …

Orbital-scale climate variability in Arabia as a potential motor for human dispersals

The Arabian Peninsula is situated at an important crossroads for the movement of Pleistocene human populations out of, and into, Africa. Although the timings, routes and frequencies of such dispersals have not yet been confirmed by genetic, fossil or archaeological evidence, expansion into Arabia would have been facilitated by humid periods driven by incursions of monsoon rainfall, potentially from both Indian Ocean and African monsoon systems. Here we synthesise terrestrial and marine core palaeoclimatic data in order to establish the spatial and temporal variability of humid periods in Arabia between late Marine Isotope Stage (MIS) 7 and 3. Incursions of monsoon rainfall occurred during periods of insolation maxima at ca. 200–190, 170, 155, 130–120, 105–95, 85–75 and 60–55ka, providing multiple ‘windows’ of favourable climatic conditions that could have facilitated demographic expansion through Arabia. Strong summer monsoons are generally associated with mid-high latitude interglacials, however, enhanced monsoon convection also brought rainfall into Arabia during global glacial phases, possibly due to a strengthened winter monsoon and a greater influence of southern hemispheric temperature changes. Key periods for dispersal into northern regions of Arabia correspond with the synchronous intensification of both eastern Mediterranean and monsoon rainfall systems at insolation maxima during MIS 7 and MIS 5, which may have facilitated demographic connectivity between the Levant and the Arabian interior. Environmental conditions throughout southern and southeast regions were also favourable to expansion during these times, although strong monsoons in these regions during MIS 6 and MIS 3 suggest further opportunities for demographic expansion and exchange. Terrestrial and marine evidence show that during early MIS 3 (ca. 60–50ka), a strengthened monsoon led to the activation of interior drainage systems and increased productivity in coastal zones, indicating that favourable environmental conditions existed along both coastal and interior routes at that time.

Great Basin mammalian diversity through time

The Great Basin is a vast area of interior drainage including much of the expanse between the Sierra Nevada and Rocky Mountains. The unique geomorphology of this region has resulted in high local and regional biodiversity. Today, the Great Basin is considered one of the most threatened bioregions in North America. In this Special Feature, we bring together a broad range of perspectives that highlight how Great Basin landscape dynamics from 30 million years ago to today, including modern anthropogenic impacts, have shaped mammalian diversity from individual populations and species to entire biomes.

Advances in research on wetlands of the Tibetan Plateau

About 80% of the global wetlands are being degraded or lost, and wetland ecosystem has become one of the most endangered ecosystems in the world. As a sensitive area to global change and protective barrier for the security of ecosystems in Asia, the Tibetan Plateau has a wetland area of about 13.19×104km2, which is an important part of the wetland ecosystem in China. With increasingly more remote sensing technology applied, Tibetan Plateau wetland research entered a new period of rapid development. This article summarizes remote sensing research literature of the Tibetan Plateau from 1992 to 2013, aiming to provide a reference for Tibetan Plateau wetland research in the future. The following aspects of research are reviewed: monitoring methods, research topics, and existing problems. The analysis shows that:(1) In the past 30 years, the research on Tibetan Plateau wetlands was focused on dynamic change monitoring of wetland area, landscape patterns, and ecological environment based on remote sensing technology. Attention was paid to building models to analyze the trend of change of the wetlands in three dimensions, taking an ecological system perspective.(2) Such research concludes that: 1) From 1990 to 2006, the wetland area generally decrease at an annual rate of 0.13%, and the landscape diversity decline at an annual rate of 0.17%. 2) In contrast, from 2003 to 2009, the depth of the lakes on the Tibetan Plateau had increased at an annual rate of 0.20 m; from 1970 to 2011, water storage of the lakes increased at an annual rate of 2.2 km3; from 1976 to 2009, lake area of the interior drainage area of the plateau increased at an annual rate of 0.83%. 3) From 1965 to 2002, change of the Tibetan Plateau wetlands was controlled by the climate. Wetland degradation and change around areas of human activity are a result of increased human activities. The existing problems of remote sensing research of the Tibetan Plateau wetlands are that: accuracy of digital analysis of remote sensing images and cloud removal need to be improved; a comprehensive perspective is needed for the research of the Tibetan Plateau wetland system. Based on the review, this article identifies the following key areas of future research:(1) Taking full advantage of remote sensing monitoring of wetlands characterized by multidate, multispectral, real- time, dynamic, and repeated coverage. Strengthening comprehensive research and remote sensing research of areas lacking conventional data;(2) Establishing a regional specific wetland remote sensing classification system that is technically operable, and conducting basic research on improving the Tibetan Plateau wetland remote sensing classification system and applications;(3) Focusing more on quantitative study on ecosystem functions of wetlands and decision support system for wetland ecosystem management;(4) Discussing responses and adaptation mechanisms of the Tibetan Plateau wetland ecosystem under the background of global change, especially the differences in responses and adaptation mechanisms under the impacts of different temporal and spatial scales. Coupling the models of hydrology, ecology, meteorology, soil, and environment to predict the trend of wetland degradation and revealing regional differences of response between different areas of the plateau in the face of global change;(5) Advancing remote sensing methods for Tibetan Plateau wetland research, strengthening the integration of RS, GIS, and GPS methods, and promoting the construction of a Tibetan Plateau wetland information platform.

도시홍수 취약성 평가에 대한 연구

내수배제 불량으로 인한 도시침수는 매년 심각한 인적, 물적 피해를 발생시키고 있다. 내수침수 피해 저감을 위한 방재정책을 수립하고, 방재대책의 우선순위를 결정하기 위해서는 대상지역의 취약성을 적절하게 평가하는 것이 중요하다. 본 연구에서는 도시지역의 침수피해 취약지역을 평가할 수 있는 모형을 개발하였다. 평가 모형은 산술적인 도시홍수 취약성 평가 방법과 Promethee를 이용한 도시홍수 취약성 평가 방법을 적용하였다. 평가인자로는 도시홍수에 직적접인 영향을 미치는 저지대 지역, 통수능력 부족관거 그리고 유출곡선 지수를 선정하였다. 평가 결과 과거 침수기록과 비교하였을 때 산술적인 도시홍수 취약성 평가 방법은 약 75%의 일치율을 Promethee를 이용한 도시홍수 취약성 평가방법은 58.3%의 일치율이 분석되었다. 본 연구에서는 도시홍수에 직접적인 영향을 미치는 인자를 활용한 산술적인 도시홍수 취약성 평가방법의 적확성을 확인할 수 있었다. Urban flood inundation by poor interior drainage systems causes annually the significant loss of life and properties in Korea. The inundation vulnerability assessment is important for policy establishment and priority decision of disaster management policy. In this study, an assessment model was developed for urban vulnerable areas. An assessment model was applied to arithmetic Urban flood vulnerability assessment and Urban flood vulnerability assessment using Promehtee(Preference Ranking Organization Method for Enrichment Evaluation). Assessment factors that directly affect urban flood were selected to lowland area, length of poor drainage sewer, and curve number. The results of assessment, inundation records are in concordance with arithmetic urban flood vulnerability assessment method about 75% and urban flood vulnerability assessment using Promehtee about 58.3%. In this study, arithmetic urban flood vulnerability assessment method using assessment factors that directly affect urban flood was confirmed by accuracy.

Geomorphology of the Tsetseg Nuur basin, Mongolian Altai – lake development, fluvial sedimentation and aeolian transport in a semi-arid environment

The landform ensemble of the Tsetseg Nuur Basin in Western Mongolia provides an archive for periods of different geomorphologic processes induced by changing climate conditions during the Holocene and late Pleistocene times. The geomorphologic map of Tsetseg Nuur basin in the Mongolian Altai illustrates the spatial relation and interaction between different types of sedimentation in semi-arid regions of Central Asia. The map is an instrument to visualize the geomorphologic settings, providing valuable information to distinguish periods of geomorphologic processes and to analyze the landscape evolution. This enables the creation of a relative morphostratigraphy of periods with different hydrological environments, mainly marked by the stages of lake level evolution in an interior drainage basin. The relative chronology calculated from the map receives an absolute chronostratigraphy through radiometric dating from selected sections investigated during field-work.

GIS를 이용한 도시유역에서의 침수위험도 평가

The flood damage is increasing at urban area by poor interior drainage systems. It is important to assess the degree of the inundation risk for the establishment of consistent disaster management policy. In this study, regression curves were estimated including four parameters (mean elevation, mean slope, impervious area, drainage system index) to assess degree of the inundation risk at urban areas. The regression equations were applied in Seoul, Korea, and the results revealed that the equations closely reflected inundation area during last 6 years. The results of this study are expected to utilize to flood management to at urban areas.

A New Species of Gymnotus (Gymnotiformes, Gymnotidae) from Uruguay: Description of a Model Species in Neurophysiological Research

Gymnotus omarorum is described from coastal and interior drainages of Uruguay, where it is locally abundant in streams and lagoons, and is not known to occur sympatrically with congeners. This species has been used for more than 30 years as a model organism in neurophysiological research, where it has been referred to as G. carapo or G. cf. carapo. Gymnotus omarorum is a member of the G. carapo species group, with which it shares the presence of two pores in the dorsolateral portion of the preopercle, irregular (wavy) dark pigment bands which usually become broken and/or lose contrast with the ground color through growth, a clear patch at the caudal end of an otherwise darkly pigmented anal fin, and more than four arrowhead-shaped (anteroposteriorly compressed) teeth in the anterior portion of the dentary. Gymnotus omarorum is readily differentiated from other members of the G. carapo species group by the following unique combination of character states: a short distance to first ventral lateral-line ramus (39–45% TL vs. 47–58%), few pored scales to first ventral ramus (27–35 vs. 40–78), many ventral lateral line rami (16–37 vs. 0–14), and ovoid (vs. elongate) scales on the posterior portion of body.

Risk Analysis of a Protected Hurricane-Prone Region. I: Model Development

A risk analysis methodology is presented in this paper for protected hurricane-prone regions. The methodology is intended to assist decision and policy makers, and has the characteristics of being analytic, transparent, quantitative, and probabilistic. The hazard is quantified using a probabilistic framework to obtain hazard profiles as elevation-exceedance rates, and the risk profiles as loss-exceedance rates that are based on a spectrum of hurricanes determined using a joint probability distribution of the parameters that define hurricane intensity. The resulting surges, waves, and precipitations are used to evaluate the performance of a hurricane protection system consisting of a series of basins and subbasins that define the interior drainage characteristics of the system. The protection against flooding is provided by levees, floodwalls, closure gates, and interior drainage system and pumping stations. Stage-storage relationships define the characteristics of subbasins and the population and property at risk. The proposed methodology will enable decision makers to evaluate alternatives for managing risk such as: providing increased hurricane protection, increasing evacuation effectiveness, changing land-use policy, enhancing hurricane protection system operations, and increasing public and governmental preparedness.

Effectiveness of Piscicides for Controlling Round Gobies ( Neogobius melanostomus)

Round gobies (Neogobius melanostomus) were introduced to the Great Lakes presumably as a result of ballast water releases from seagoing freighters returning from European water bodies. These unwelcome fish have become established in the Great Lakes region and are expanding their range to suitable portions of other interior drainage basins including the Mississippi River traversing the central United States and the Trent-Severn waterway spanning south-central Ontario. If the invasion continues, use of chemical toxicants as a control measure may be necessary. Toxicity tests of the currently registered piscicides antimycin, rotenone, 3-trifluoromethyl-4-nitrophenol (TFM), and Bayluscide ® were conducted with three fish species native to the Great Lakes and round gobies collected from the Illinois Waterway. Tests indicated that round gobies are sensitive to all of the piscicides, however, the level of sensitivity is similar to that of the native fish species tested. Therefore, currently registered piscicides have limited potential to selectively remove round gobies. Bottom-release formulations of Bayluscide ® and antimycin were also evaluated as control agents for the normally bottom-dwelling round goby. Avoidance behavior tests demonstrated that the round goby did not react to the presence of either chemical. Therefore, the bottom-release formulations may have some application for the selective removal of round gobies, and may be one of the few tools presently available to fishery managers to help limit the range expansion of this invasive fish.