Upstream River Research Articles

Mapping the Social, Economic, and Ecological Impact of Floods in Brisbane

Flooding has become one of the most dangerous and expensive disasters due to urbanization and climate change. Tools for assessing flood impact are required to support the shift of flood mitigation management from post-disaster recovery and reconstruction to community-driven pre-disaster warning and preparation. This study aims to develop an integrated approach to spatially assess the economic and social losses and ecological gain and identify the geographical factors of locations with high impacts of floods in Brisbane using the datasets collected from both the 2011 and 2022 flood events. Water depth, inundated area, land cover, ecosystem service value, mortality, and morbidity were considered to assess flood impacts. It is found that downstream (above 23,500 m from the upper stream) riverside communities (within 800 m of the river) with low altitudes (below 15 m) are more likely to experience significant flood damage. Flood impacts have bell-shaped developments with elevation and direct distance to the upstream river source and an exponential decline with distances to the river. These findings have implications for formulating future urban land use and community-tailored mitigation strategies, particularly for flood warning and preparation.

Study of Drainage Channel Capacity on Jalan Masangan Kulon Sukodono Sidoarjo

A problem often faced by people in urban areas is flooding in residential areas during the rainy season. The causes of flood inundation include land conversion, which was originally an open area turned into a built-up area for settlements, industry or trade and offices. Land use that is not orderly causes the issue of drainage channel capacity in urban areas to be very complex. This study aims to assess the capacity of drainage channels located on Jalan Masangan Kulon so as not to hamper traffic flow and harm the activities of the surrounding community and the handling carried out to overcome flooding in the existing. The method of calculating the flood plan for this drainage case study uses the Rational Method with a 2-year return period. Data collection is done by observation, taking measurements and channel normalization. Evaluation of channel capacity is carried out to assess the ability of drainage channels to plan discharge. The results obtained in this study Flood discharge in the upstream river with a return period of 2 years amounted to 1.54 m³/second. Areas that experience flooding occur in Segments 10-17 and 18-19. In segment 10-17 the block discharge is 3.98 m³/second and the existing discharge is 3.389 m³/second. After normalizing the existing discharge is 4.34 m³ / second. In segments 18-19 the block discharge is 5.228 m³/second and the existing discharge is 4.647 m³/second. After normalizing the existing discharge is 5.760m³/second.

Anthropogenic Geomorphology of the Magoye Riverine Landscape, Zambia

Aims: This study sought to investigate the role of humans in modification and creation of landforms in river channels with specific focus on the Magoye River. The objectives of this study were to: document geomorphic characteristics of Magoye River, assess anthropogenic activities and landuse/cover change in the buffer zone and, examine key anthropogenic river landforms. Study Design: This study was inspired by analytic eclecticism research philosophy and adopted mixed methods, particularly concurrent research design. Methodology: The landcover images were analysed using image processing tools in ArcGIS 10.4 for the periods 1990, 2005 and 2020. Descriptive statistics were used to quantitatively visualize the changes in land cover/use. The data was collected using field observation, photography, GPS and a Likert scale tool and, analysed using descriptive statistics, specifically frequency graphs showing mean and standard deviation. Results: The results showed that sand mining and brick moulding accounted for almost 68% of human activities in the 11.48 km2 delineated buffer zone by 2020, compared to 35% in 1990. These punctuated creation of sand conical heaps, stone bunds, pot holes and pools, shallow wells on the river bed, gullies induced by water accessed points, which weakened river banks. Generally, sand mining and brick moulding were the most severe in the buffer zone and they created wide range of deformations riverbanks and beds. The findings further revealed that Magoye River had geomorphologically evolved into Reservoir River covering 80% on the upstream (139.4km) and Sand Bank River accounting 20% on downstream (27.6 km). Conclusion: The study concludes that, the catchment and buffer zone have undergone degradation propelled by anthropogenic activities, which have punctuated channel morphological degradation. Although the Magoye River channel was highly damaged, it was not beyond regeneration if restoration measures, were collaboratively identified and implemented with the local communities.

Geospatial dataset for hydrologic analyses in India (GHI): a quality-controlled dataset on river gauges, catchment boundaries and hydrometeorological time series

Abstract. Streamflow gauging stations not only track the pulse of rivers but also act as common reference points for hydrologic and other environmental analyses. As such, streamflow data and metadata on gauging stations – Geographic Information System (GIS) data on station locations, their upstream catchment boundaries and river flow networks – are critical for analyses. However, for India's river basins, the availability of such data is limited; when available, data are not in an analysis-ready format and can have substantial errors. Studies often use available information from India's water agencies as is, without checking its validity. This study addresses the above limitations by building a new dataset using existing metadata (from the Central Water Commission, CWC, and the Water Resources Information System, WRIS) and checking it against publicly available information from global data sources (e.g., World Wildlife Fund, Multi-Error-Removed Improved-Terrain Hydro and Copernicus) and online maps (e.g., Google Maps). The quality control process categorizes existing metadata based on their consistency with these sources; also, existing metadata are supplemented with additional information where needed. The new dataset developed here is called the “Geospatial dataset for Hydrologic analyses in India” (GHI) and uses Hydrological data and maps based on Shuttle Elevation Derivatives at multiple Scales (HydroSHEDS) data as the underlying template. GHI has both geospatial and time series information. In this initial version of GHI, the spatial domain includes only the river basins of Peninsular India where daily streamflow data are publicly available. Following the quality control process, the CWC's 645 stations in Peninsular India were categorized into three groups: Group 1 (reliable metadata and adequate daily streamflow data; 213 stations), Group 2 (reliable metadata and inadequate or no daily streamflow data; 259 stations) and Group 3 (missing or unreliable metadata; 173 stations). For each of the 472 stations falling into groups 1 and 2, catchment-specific annual and monthly time series spanning 71 water years (1950–2020) of the following were compiled: observed precipitation from the Indian Meteorological Department (IMD); observed streamflow from WRIS; estimated precipitation, evapotranspiration (ET) and streamflow from ERA5-Land; and ET from the Global Land Evaporation Amsterdam Model (GLEAM). A preliminary analysis of catchment-scale time series of data indicates that, while the compiled data appear reasonable over most of the study domain, spurious runoff–precipitation ratios were observed in the hilly coastal regions of Western India. This adds to yet another data-related obstacle faced by the hydrologic community. In order to quantify historical changes and reconcile them with anticipated future changes, the community needs robust and reliable hydrographic and hydrometeorological datasets as well as unrestricted access to such datasets. The goal of this study is to highlight the limitations of existing datasets and pave the way for a community-led effort towards building the needed datasets. GHI serves as a placeholder until such datasets become available. Potential improvements to GHI are discussed. GHI is publicly available at https://doi.org/10.5281/zenodo.7563599 (Goteti, 2023).

Hydrologic and Organic Carbon Quality Controls on Nitrous Oxide Dynamics Across a Variably Confined Karst Aquifer

AbstractAtmospheric concentrations of the potent greenhouse gas nitrous oxide (N2O) have increased approximately 20% since the pre‐industrial era. Riverine systems represent an important atmospheric source of N2O however, the influence of varying hydrogeological conditions and dissolved organic carbon (DOC) quantity and quality on N2O dynamics remains poorly understood. We investigate effects of these processes on N2O dynamics in the Santa Fe River watershed in north‐central Florida, USA where a gradient in DOC quantity and quality is caused by varying surface water‐groundwater exchange. The watershed is underlain by the karstic Floridan aquifer, which is confined in the headwaters and contains terrigenous recalcitrant DOC, while the unconfined lower reaches contain protein‐like labile DOC substrates. Where extensive surface water‐groundwater exchange occurs at the boundary between the confined and unconfined aquifer, incomplete denitrification raises N2O concentration to 6.1 μg N‐N2O L−1, approximately 20 times greater than the concentration expected from equilibration with atmospheric N2O. These elevated concentrations create average local fluxes reaching ∼950 μg N‐N2O m−2 hr−1 within the mixing zone. Summation of spatially explicit emission estimates for upstream, mixing zone, and downstream river sections yield a total average emission rate of ∼3,758 kg N‐N2O yr−1. Despite having the smallest surface area across the river transect (∼8%), emissions from the mixing zone account for 26% of the total river emission rate. These findings highlight the potential contributions from karst landscapes to N2O cycling caused by varying redox conditions during surface water‐groundwater exchange, which creates hotspots of N2O production and emissions.

Identifying bridges prone to instream wood accumulation: insights from bridges across the UK

Accumulation of instream large wood (i.e., fallen trees, trunks, branches, and roots) at bridges during floods may exacerbate flooding, scour and cause structural failure. Yet, explaining and predicting the likelihood of a bridge trapping wood remains challenging. Quantitative data regarding wood accumulation at bridges are scarce, and most equations proposed to estimate the accumulation probability were derived from laboratory experiments, and include variables such as flow velocity, Froude number, and approaching wood volume or size which are difficult to obtain. Other evaluations based on technical reports and information regarding wood removal have been proposed but are mostly qualitative. Until now, a data-driven approach combining multiple quantitative accessible variables at the river reach and catchment scales remains lacking. As a result, the controlling parameters explaining whether a bridge is prone to trap wood are still unclear. This work aims to fill this gap by analysing a database of 49 bridges across the United Kingdom (UK) classified as prone and not prone to wood accumulation. The database contained information regarding the geometry of the bridge (i.e., number of piers and pier shape) and we added parameters describing the upstream river channel morphology, the riparian landcover, and high-flow characteristics. We applied multivariate statistics and a machine learning approach to identify the variables that explained and predicted the predisposition of bridges to wood accumulation. Results showed that the number of bridge piers, the unit stream power, the pier shape, and the riparian forested area explained 87% of the total variability for the training dataset (0.87 training accuracy), and the selected model had a testing accuracy of 0.60 (60%). Although limited by the sample size, this study sheds light on the identification of bridges prone to wood accumulation and can inform bridge design and management to mitigate wood-related hazards.

Characterization of organic phosphorus in soils and sediments of a typical temperate forest reservoir basin: Implications for source and degradation

Reservoirs can intercept upstream inputs and greatly alter their migration and transformation processes at a basin scale. Taking a typical reservoir basin in the Xiaoxing'an Mountains of Northeast China as an example, the organic phosphorus (Po) and organic matter (OM) compositions in the upstream soil, river and reservoir sediments were characterized by 31P NMR, stable carbon (δ13C) and nitrogen isotopes (δ15N), and the migration and transformation processes of Po from soil to reservoir sediments were explored. The compositional data indicated that both the OM and Po in the reservoir were mainly imported by C3 plants from the upper reaches. Higher monoester phosphorus (P) components in the upstream soils than in the reservoir sediments, which indicated the migration and degradation process of Po from the upstream soils to the river and then to the reservoir sediments. The degradation rate of monoester P was higher, approximately 30.6% and the phosphonate fraction had the lowest degradation rate, about 0.4%. Specifically, the degradation of monoester P including inositol P was higher than that of organic carbon. Thus, at the basin scale, more forest-derived organic carbon was likely intercepted by reservoirs and precipitated to sediments, while Po might degrade to a greater extent. Aggregative results showed that reservoirs may play an important role in the differentiated migration and transformation process of forest-derived OM and Po. And then, the highly degradable Po including inositol P poses a greater risk of eutrophication in the typical temperate forest reservoirs and their downstream, even the ocean, and is accompanied by possible algal blooms in the future. Information derived from this study provides a more scientific basis for the assessment of the ecological and environmental effects of reservoir and dam construction projects.

Field monitoring of river ice processes in the vicinity of ice control structures in the province of Quebec, Canada

Over the past decades, a variety of ice control structures (ICSs) have been designed and built, but to date, there has been no systematic evaluation of the effectiveness of these structures. To achieve this objective, first an understanding of the interaction between different ice processes and the ICSs must be established. For this purpose, a total of four ICSs located in the province of Québec were monitored during the 2021–2022 winter. The results showed that the ice jam holding time could vary from 1.5 to 68.5 h. The release of the jam was mechanically driven when the ratio of release to initiation Froude number was higher than one and was thermally driven when this ratio was lower than one, and the water temperature increased between initiation and release. Also, as the ratio of the total pier spacing to upstream river width increased, the holding time decreased.

Discrete Streamflow Measurements and Waterborne Self-Potential Logging of a 43-Kilometer-Long Reach of the Elm Fork Trinity River Upstream from Dallas, Texas

Continuous and discrete streamflow data were combined with waterborne self-potential (WaSP), surface-water temperature and surface-water conductivity surveys obtained along an approximately 43-kilometer (26.7 miles) surveyed reach of the Elm Fork Trinity River (hereinafter referred to as “Elm Fork”) upstream from Dallas, Texas, to investigate areas of gaining and losing streamflow under various streamflow and seasonal climatic conditions. Discrete streamflow measurements were made at 17 locations on October 12, 2021, and January 25, 2022, at 19 locations on May 17, 2022, and at 18 locations on August 9, 2022. WaSP data were measured from a kayak in January 2022 during a period of base flow along three individually surveyed reaches between the Lake Lewisville Dam and Frasier Dam on the Elm Fork. Together, these data indicated different parts of the Elm Fork functioned as either a gaining or losing stream depending on streamflow and seasonal climatic conditions. Overall, there were estimated net gains in streamflow during the first two discrete-measurement events of about 107 cubic feet per second (ft3/s) and 2 ft3/s in October 2021 and January 2022, respectively, and estimated net losses in streamflow in May 2022 and August 2022 of about 24 ft3/s and 18 ft3/s, respectively.

Global change scenarios in coastal river deltas and their sustainable development implications

Deltas play a critical role in the ambition to achieve global sustainable development given their relatively large shares in population and productive croplands, as well as their precarious low-lying position between upstream river basin development and rising seas. The large pressures on these systems risk undermining the persistence of delta societies, economies, and ecosystems. We analyse possible future development in 49 deltas around the globe under the Shared Socio-economic and Representative Concentration Pathways until 2100. Population density, urban fraction, and total and irrigated cropland fraction are three to twelve times greater in these deltas, on average, than in the rest of the world. Maximum river water discharges are projected to increase by 11–33 % and river sediment discharges are projected to decrease 26–37 % on average, depending on the scenario. Regional sea-level rise reaches almost 1.0 m by 2100 for certain deltas in the worst-case scenario, increasing to almost 2.0 m of relative rise considering land subsidence. Extreme sea levels could be much higher still—reaching over 4.0 m by 2100 for six of the 49 deltas analysed. Socio-economic conditions to support adaptation are the weakest among deltas with the greatest pressures, compounding the challenge of sustainable development. Asian and African deltas stand out as having heightened socio-economic challenges—huge population and land use pressures in most Asian deltas and the Nile delta; low capacity for adaptation in most African deltas and the Irrawaddy delta. Although, deltas in other parts of the world are not immune from these and other pressures, either. Because of unique pressures and processes operating in deltas, as in other “hotspots” such as small islands, mountains, and semi-arid areas, we recommend greater consideration and conceptualisation of environmental processes in global sustainable development agendas and in the Integrated Assessment Models used to guide global policy.

Elements and omega-3 fatty acids in fishes along a large, dammed river

Damming of a river can trap and elevate levels of sediment-bound elements and alter food web dynamics in created reservoirs. It follows that dams may alter how elements and other nutrients, like the beneficial omega-3 fatty acids (n-3 FAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are accumulated in fish and thus the chemical composition of species above and below this barrier to migration. This study examined the spatial and species differences in contaminants and nutrients in fish from the Wolastoq | Saint John River (New Brunswick, Canada) in association with a large hydroelectric dam (Mactaquac Generating Station; MQGS), a river which supports both recreational fisheries and subsistence fishing by Indigenous communities. In 2020 and 2021, Smallmouth Bass, Yellow Perch, American Eel, and Striped Bass were collected from locations upstream (reservoir and river) and downstream of the MQGS and analyzed for mercury (Hg) and 30 other trace elements, n-3 FAs, δ15N, and δ13C. Fish from the reservoir were highest in the beneficial elements P, S, and K, while fish from upstream of the reservoir had lower levels of toxic elements, including Hg. The dam appeared to alter food web dynamics, as fish from the reservoir and immediately downstream of the dam had higher δ15N and reservoir fish were depleted in δ13C. DHA and Hg were positively corelated with δ15N, and EPA in Smallmouth Bass was higher in sites where fish had higher δ13C. Overall, this study suggests that the dam altered food web dynamics and the uptake of contaminants and nutrients by fish, and that location and species are important factors when examining the risks and benefits of consuming wild fish from a system impacted by a large dam.

Stable isotopes reveal the surface water-groundwater interaction and variation in young water fraction in an urbanized river zone

Based on 30 sampling campaigns on precipitation, river water and groundwater in Qingbaijiang urban catchment, southwest China, this study reports the spatio-temporal evolution of water isotopes under the impacts of human activities. The seasonal variation of groundwater-surface water interaction is quantitatively evaluated by isotope-aid hydrograph separation, and the young water fraction (Fyw) in river water at different spatial locations is estimated based on the seasonal periodicity of isotopes. The results show that the stable isotopes in river water and groundwater in Qingbaijiang urban catchment grow enriched from upstream to downstream, reflecting the transformation of the dominant water source from plateau river water to local precipitation and the influence of evaporation. The operation of water conservancy projects and construction of impervious surface in urban areas increase the evaporation intensity of river water. The results of the end-member mixing analysis (EMMA) demonstrates that the average annual contributions of river water to near-bank groundwater are 60.17%, 23.55% and 24.90% in the upper, middle and lower parts, respectively. The periodic storage and release of water led by the water conservancy projects enhances the groundwater recharge in the upstream river, while the water exchanges between river water and groundwater in the middle and lower parts of the catchment are reduced. The Fyw at 8 river sections of Qingbaijiang River estimated by the isotopic amplitude ratio method ranges from 0.067 to 0.194, with an overall increasing trend from upstream to downstream. The young water fraction is negatively correlated with mean elevation, mean slope and vegetation coverage, while positively correlated with the proportion of anthropogenic land use and the proportion of low-permeable soil. The construction of impervious surfaces and drainage systems in urban and rural areas is an important driver for the elevated young water fraction.

Community-Driven Insights into Fish Assemblage, Microhabitats, and Management Strategies in the Meghna River Basin of Bangladesh

The present study aimed to delve into the local ecological knowledge of fisheries in the Meghna River Basin (MRB) of Bangladesh by exploring the insights and perspectives of local communities. A survey was administered among six fishing communities from five districts along the MRB between August 2015 and January 2016 to accumulate data for this study. The study sites were selected meticulously based on three crucial criteria: upstream river, coastal area, and fish sanctuaries, which covered three major rivers, namely the Meghna, Andharmanik, and Payra. The study employed participatory rural appraisal (PRA) tools, including 120 individual interviews using purposive sampling, 25 focus group discussions, and 36 key informant interviews. The study identified the ten most frequently caught fish species along with their temporal and spatial variation as reported by the respondents. Nine of these species fell into the least concern category, which indicate their stable population status. Meanwhile, six out of ten species cited as highly caught in the previous one to two decades belong to the threatened or near-threatened category. Findings also reveal that fishers are able to recognize important microhabitats of the study area and their significance for fish species. In addition, fishers identified the negative drivers of ecosystem degradation as well as suggested several management measures to address these challenges. The results of this study underscore the critical role of engaging with local communities and integrating their ecological knowledge into initiatives for the sustainable exploitation and conservation of aquatic resources in the MRB.

A Physically‐Based Reverse‐Stage Routing Model Considering Lateral Flow for Establishing Normal Rating Curves at Ungauged Upstream River Sections

AbstractMany of the world‐rivers are often ungauged or poorly gauged due to inadequate streamflow monitoring networks. Even with the limited available monitoring stations, only a few of them monitor both stage and discharge data. But when there is a need for estimation of discharges at a gauging station, where only stage data is monitored, one may employ a reverse routing technique using the stage data monitored at a nearby downstream gauging station. This study develops a novel single‐parameter reverse‐stage routing (RSR) model based on the second‐order approximate water surface gradient governing equation to estimate stage and discharge at any scantily‐gauged upstream river section using the known stage information available at the downstream section. A novel criterion is also developed for checking the applicability of the RSR model. Reverse routing experiments, carried out by the RSR model using different hypothetical downstream stage hydrographs in a number of hypothetical trapezoidal and rectangular channel reaches to reproduce the benchmark upstream stage and discharge hydrographs, demonstrate the good performance of the RSR model with the Nash–Sutcliffe Efficiency >98%, absolute volume conservation error <1.5%, and an absolute error in peak ≤1%. Subsequently, the RSR model was tested for three real‐river case studies in India and Italy with good reproduction performances, and along with the development of the corresponding normal rating curves at the upstream river sections. The study results reveal that the parsimonious RSR model has good potential for solving reverse routing problems with stable numerical solutions for rivers under ungauged and scantily‐gauged scenarios.

Evaluation of Disturbance Zonation of Bagmati River System using Benthic Macroinvertebrates in the Kathmandu Valley, Nepal

The existence of Nepal's holy river, Bagmati, which flows through the core of Kathmandu Valley has been menaced by many anthropogenic threats. It is necessary to identify how vulnerable it has been. This research focuses on the evaluation of disturbance zonation to analyze the Bagmati River System’s spatial biological health. Benthic macroinvertebrates (BMIs) were used as biological indicators and were sampled from upstream to downstream using a multi-habitat sampling approach during the post-monsoon period in 2021. The Ganga River System Biotic Score/Average Score per Taxa (GRSBIOS/ASPT) was used to assess river water quality. From the sampling of 21 sites, a total of 5839 individual BMIs from 51 Families and 11 Orders were recorded. Upstream accounted for more than 30% of all the families, making upstream rich in taxonomic preferences, which steadily decreased from midstream to downstream. Facultative taxa were widely distributed in both upstream and midstream, but sensitive taxa were limited to upstream only. There are no signs that facultative and sensitive taxa existed downstream and were fully dominated by pollution-tolerant species. According to classification, the upstream river within Shivapuri Nagarjun National Park of the Bagmati River System was clean and was categorized as Class I, whereas rivers from the boundaries of the protected area to downstream were categorized as Class IV-V with few sites as Class II and Class III, indicating that this stretch of the river was extremely polluted. Water resource managers should utilize the study's findings to assess and restore the water's quality using biological indicators.

Microplastics in green mussels (Perna viridis) from Jakarta Bay, Indonesia, and the associated hazards to human health posed by their consumption.

The Jakarta Bay is the estuary for thirteen rivers that flow through densely populated and industrialized upstream regions. This condition has the potential to pollute the Jakarta Bay with microplastics that are transported from the upstream river. Meanwhile, people, particularly fishermen, continue to use Jakarta Bay for fishing and aquaculture. This study examined microplastics (MP) abundance in the whole tissues of green mussels (Perna viridis) grown in Jakarta Bay, Indonesia, and their health risks. MP was identified in all 120 green mussels, with fiber > film > fragment being the most common kinds. The abundance of fiber was 19 items/g of tissue, whereas the abundances of fragments and film were 14.5 items/g and 15 item/g, respectively. Fourier transform infrared spectroscopy tests on MP from the tissues of green mussels showed that there were 12 different types of MP polymers. The estimated amount of MP that humans consume each year varied from 29,120 MP items/year to 218,400 MP items/year for different age groups. Based on the total mean number of MP found in the tissues of green mussels and the amount of shellfish consumed per person in Indonesia, it was estimated that people ate 775,180 MP through shellfish each year.

Exploring fish functional trait assemblages in Eastern Mediterranean rivers: a study across multiple scales using network analysis

Functional traits of river fish assemblages have rarely been studied in the Eastern Mediterranean region. A dataset of 254 Greek electrofished near-natural sites (427 samples) was analyzed to explore native fish functional structure across three spatial scales: (a) among six ecoregions, (b) within a single ecoregion, and (c) in a river basin. Overall, 76 native fish species were assigned eight functional categories, involving 24 different traits. Bipartite networks were used to interpret spatial patterns of species trait data. Two major trait assemblage types were detected in all three spatial scales: the upland type, dominated by insectivorous, benthic, rheophilic, intolerant species, and the lowland type, incorporating omnivorous, limnophilic, phytophilic, and tolerant species. In order to provide further insights between traits and key environmental variables, redundancy analysis (RDA) was employed. The RDA depicted a strong upstream–downstream environmental gradient. Upland and lowland assemblage types form two distinct functional zones along the upstream and downstream river stretches, respectively. Yet, no consistent boundary criteria seem to exist between them. Notably, within a region of high fish assemblage heterogeneity such as the Eastern Mediterranean, functional patterns follow well-established phenomena along the upstream–downstream longitudinal profile of temperate lotic waters.

Intensified intrusion and retention of saltwater in the Sumjin River Estuary, South Korea

The Sumjin River Estuary (SRE) is located in South Korea and is a natural riverine system without an estuarine barrage. Civil complaints have been expressed by residents surrounding the SRE, particularly with regards to the extended upstream saltwater intrusion and the diminished production of the Corbicula japonica clam. To establish a scientific background of the complaints, more than 75 surveys across the SRE were performed, including gathering of long-term CTD monitoring data in the middle reaches of the SRE during 2015–2017. Although salinity at the mooring station normally fluctuates between zero and 20 psμ with tidal variation, the salty (>15 psμ) bottom water is consistently retained in the bathymetric depression of the middle reaches of the SRE, the main habitat for the benthic C. japonica clam, particularly during the neap tide and periods of moderate freshwater discharge. The maximum saltwater intrusion distance upstream of the estuary increased from 22.6 km to 24 km during the decade between 2005 and 2015. In addition, saltwater intrusions greater than 20 km have become more frequent over the decade. The increased utilization of freshwater in the upstream river reaches has been considered a primary constraint of the intensified saltwater intrusion in the SRE. This is enhanced by freshwater abstractions from an intake located near the SRE, particularly during low precipitation periods. The saltwater retention on the river bottom and the intensified saltwater intrusion upstream imply that estuarine ecosystem management policies are needed to incorporate salinity monitoring near the river bottom, where benthic organisms occur. The abstractions at the upstream freshwater intake are also recommended to be carefully controlled, particularly during the dry season.

Conservation and characterization of karst water using morpho-hydrogeological methods in Pindul Cave system, Gunungsewu Karst, Java, Indonesia

Pindul Cave system is one of the essential water resources in Wonosari Basin. Pindul Cave has a perennial flow and is used to cave tubing. Administratively, this research was conducted in Pindul Cave and its surrounding areas located in Karangmojo District, Gunungkidul Regency. The aim of this research are: (1) to analyze the underground flow system in Pindul Cave (2) to estimate the catchment area of Pindul Cave using morphology approach (3) to propose management action of the catchment area. The method used in this study using a survey method that is divided into several stages include the preparation stage, the fieldwork stage, and the post-field stage. The preparation stage includes site selection study, discharge measurement site selection, site selection, and injection of dye tracer. The fieldwork stage is ground check survey, discharge measurements, and tracer tests. The post-field stage is analyze breakthrough curve, and making the management action of catchment area. The results of this research are: (1) based on tracer test result show that, Pindul cave stream is supplied from 2 sources, namely those originating from the cave system and those originating from surface runoff; (2) the estimated catchment area of the Pindul Cave system using a morphological approach is 15,44 km2; (3) Propose management action for the catchment area of the Pindul Cave system are not mining in the upstream area, not throwing garbage in the upstream underground river, continuing to apply the rules with restrictions on visitors to Pindul Cave in accordance with the carrying capacity.

Berobat Kampung: Religion and Traditional Knowledge of Seeking Recovery in Borneo

This article explores the variants of tradition in seeking recovery within a group of religious community in the upstream Kapuas in Borneo island. It is presented using indigenous psychology, narrative analysis and psycho-anthropology. The data were collected using the techniques of in-depth interviews, psycho-anthropological observations, narrative interpretation and documentation. This work finds that the use of Quranic verses and dhikr as well as religious symbols are are very prominent. The people of the upstream Kapuas river interpret and leave a legacy for traditional healing, beginning with an "agreement", reciting a prayer, enhancing, testing to form and hardening. Passing occurs in a closed, difficult and secret process. The preservation of traditional healing is due to very important facts; that it is low cost, being located far from modern health facilities and short time between risk of death and health resources. In addition, the traditional healers are always ready, providing fast treatment, guaranteed recovery from certain types of diseases. This article suggests that the Sufistic-style traditional healing is profound within the tradition.