Climate change and more extreme weather patterns are already being experienced as it is evident in in the form of severe negative impacts on food production, food security and natural resources all over the globe (IPCC, 2013). Sub-Saharan Africa has been portrayed as the most vulnerable region towards the impacts of global climate change because of its reliance on agriculture which is highly sensitive to weather and climate variables such as temperature, precipitation and extreme events. Africa also has low capacity for adaptation (Hertel et al., 2010).Tanzania is already affected by climatic variability and extreme weather events. Studies already show dim figures indicating continuing failure in agricultural productivity in Tanzania resulting from climate change and variability (URT, 2002). These projections raise serious concerns about agricultural development in Tanzania which has been a key driver of economic development ensuring food security and generating rural incomes as well as foreign exchange earnings. Noticeable effects of climate change have been observed Panganiriver basin that is located in the Northeastern part of Tanzania. Incidences of crop failures in the basin occur quite frequently due to erratic rainfall leading to low agricultural productivity (Mtalo et al., 2010).
Climate change present new development challenges particularly in Sub-Saharan countries where the majority of the population depend on climate-sensitive activities such as rain-fed agriculture. This necessitates for a need to focus on impacts of climate change and compatibility of adaptation as a way of providing sustainable solutions to reduce the vulnerability of the majority of poor Sub-Saharan communities. This study employed Ricardian approach to assess the impacts of temperature and rainfall variability on the net revenue from two main food crops (maize and beans) from PanganiRiver Basin produced primarily under rain fed agriculture. The study also employed the gross margin to assess the compatibility of irrigation adaptation strategy. The results indicate that increase in temperature and decrease in rainfall has decreased the net revenue from maize and beans production and raised rent for irrigated farms particularly in the middle and low altitudes of the basin. Increase in temperature has increased the net revenue from maize and beans production in the upper altitudes of basin.
Received: 11 November 2017 – Revised: 12 March 2018 – Accepted: 19 April 2018 – Published: 29 May 2018 Abstract. This study was designed to investigate the dynamics of current and future surface water availability for different water users in the upper PanganiRiver Basin under changing climate. A multi-tier modeling tech- nique was used in the study, by coupling the Soil and Water Assessment Tool (SWAT) and Water Evaluation And Planning (WEAP) models, to simulate streamflows under climate change and assess scenarios of future water availability to different socio-economic activities by year 2060. Six common Global Circulation Mod- els (GCMs) from WCRP-CMIP3 with emissions Scenario A2 were selected. These are HadCM3, HadGEM1, ECHAM5, MIROC3.2MED, GFDLCM2.1 and CSIROMK3. They were downscaled by using LARS-WG to sta- tion scale. The SWAT model was calibrated with observed data and utilized the LARS-WG outputs to generate future streamflows before being used as input to WEAP model to assess future water availability to different socio-economic activities. GCMs results show future rainfall increase in upper PanganiRiver Basin between 16–18 % in 2050s relative to 1980–1999 periods. Temperature is projected to increase by an average of 2 ◦ C in 2050s, relative to baseline period. Long-term mean streamflows is expected to increase by approximately 10 %. However, future peak flows are estimated to be lower than the prevailing average peak flows. Nevertheless, the overall annual water demand in Pangani basin will increase from 1879.73 Mm 3 at present (2011) to 3249.69 Mm 3 in the future (2060s), resulting to unmet demand of 1673.8 Mm 3 (51.5 %). The impact of future shortage will be more severe in irrigation where 71.12 % of its future demand will be unmet. Future water demands of Hy- dropower and Livestock will be unmet by 27.47 and 1.41 % respectively. However, future domestic water use will have no shortage. This calls for planning of current and future surface water use in the upper PanganiRiver Basin.
The phylogenetic relationships of Barbus species from different localities in Malagarasi and Panganiriver ba- sins were inferred with cytochrome b nucleotide sequenc- es. Malagarasi and Pangani rivers are believed to belong to the same catchment prior to the uplifting of the Tanza- nian central plateau [12,13], and that fish species in the two river systems have had similar intraspecific genetic composition due to interbreeding and natural mixing of their populations . The results obtained in the present study however, showed that the current populations of Barbus species from the two rivers are of two different genetic lineages (Figure 2) due to the consequences of geographical separation of the central plateau in the Mi- ocene era .
Wireless sensor networks (WSN), when applied to the field of water quality monitoring and management, has the potential to bring numerous benefits as compared to traditional methods since it is accurate, reliable in remote areas and in the tough condition such as during rainy seasons, and less costly. With the ever-growing application of Internet of Things (IoT) and technology in general, sensor devices have become less expensive and widely used in many applications that require remote monitoring. In this work, we present an innovative and secure water monitoring and management system using remote sensor prototype, which has been developed to monitor physiochemical parameters including pH, Turbidity, Temperature, and Dissolved Oxygen. Qualitative research methods were used for gathering system requirements through questionnaires and interviews conducted in Pangani water basin authority, in the United Republic of Tanzania. Documents were also reviewed to provide secondary knowledge. Furthermore, the system was developed using Dynamic System Development Methodology (DSDM). Firstly, the proposed system prototype is able to provide real-time measurements accurately. Secondly, the proposed system uses Advanced Encryption Standards to provide a secure transmission and storage of data transmitted from remote sensor nodes to a central database system. Thirdly, the web application was developed for data visualization using tabular and graphical formats. Lastly, the system prototype provides decisions support on quality of water present in Panganiriver basin by evaluating sensor measurements and sends SMS alerts once the measured value is above the recommended standard values.
Tanzania has one of the highest undernutrition burdens in East and Southern Africa, threatening not only individual lives but also the next generation’s economic advancement, and loss of income and opportunities. Nationwide, 34% of children under-five are stunted or short for their age, which is a sign of chronic malnutrition. Five per cent of children under-five are wasted or too short for their height, a sign of acute malnutrition. Fourteen per cent of children are underweight or too thin for their age as reported in the TDHS-MIS, 2015-2016 (Ministry of Health Community Development Gender Elderly and Children (MOHCDGEC), 2016). The regional prevalence indicates that Rukwa (56%), Njombe (49%) and Ruvuma (44%) regions have the highest prevalence of stunting. Even though Tanga is among the regions with moderate prevalence of stunting (39%) but it has the highest stunting level along the coast of the Indian Ocean as compared to Dar es Salaam (14.6%), Lindi (35.2%) and Mtwara (37.7%); (MOHCDGEC, 2016). The study was conducted in Pangani District, which is part of PanganiRiver that empties its water into the Indian Ocean.
For centuries, man has modified running waters [ 51 ]. In alpine rivers, production of hydropower results in a wide range of environmental disturbances of river systems [ 66 ]. To date, two different types of power plants are commonly in use: (1) run-of-river power plants that continuously pro- cess the incidental discharge and the impoundment upstream of such dams provides only marginal storage capacity; and (2) huge reservoirs that were built in the alpine headwaters of many streams, storing a significant water volume during times of snowmelt and rainfall. These seasonal storage plants produce energy only when there is a demand and are brought online almost exclusively during periods of peak consumption. Hydropower is an extremely important energy source in all alpine countries. With an annual production of 38 TWh, Switzerland’s hydroelectric power plants provide 58% of the domestic energy production. Approximately 60% of this production is generated in the Alps [ 67 , 76 ]. The two main Swiss hydropower production stations of the Grande Dixence hydropower scheme in the catchment of the River Rhone, for example, turbinated 611 millions m 3 of water in 2003, resulting in a total annual energy production of 2,877 GWh [ 24 ]. Peak production from storage reservoirs plays a key role in stabilizing the European power grid. M. Fette and C. Weber contributed equally to this work.
Abstract. The Saigon River system is one of the largest resources contributing water supply for domestic and industrial fields in the Ho Chi Minh City and Binh Duong Province where the drought issue is occurring at downstream area in recent years . To manage the water resources in Saigon Basin effectively, the groundwater and river interaction parameter needs to be assessed systematically. However, in the past researches, the parameters seem to be less described with full understandings. In this study, a groundwater modeling of the main stream of Saigon River was applied to analyze groundwater and river interaction parameter along the river. The interaction layer was defined as a combined layer by materials of riverbed and materials of aquitard or aquifer. The values of conductance, through groundwater model calibration by piezometric heads during 2000 to 2007 at three cross-sections in Saigon River, were used to estimate the interaction parameter (K i M -1 ) at correlative cross-section. A function of interaction
Following the cosmological principles, the main village thorough fares are aligned on the kaja/kelod and kangin/kauh axi forming an auspicious crossroad, the pampatan agung. It is at this intersection where the village square, bacingah, exists, where village life is most active and where the village draws its "power" from. The bacingah exudes a layer of geomancy similar to dwelling plans. The residence of the ruling family or family of closest descendant to the village founders, considered a palace (puri), occupies the kaja- kangin corner of the square. The village market (pasar), a meeting pavilion (wantilan), signal tower (bale kul-kul), and often an empty field (alun-alun) are located along the kelod and kauh edges. 3 In many instances a large banyan tree (beringin), auspicious to the Balinese, preferably occupies space in the kaja direction adjacent to the dwelling of a Brahmana priest (griya) (Howe 2005, 11). Today, the picturesque ideal of the village square and original crossroad is often hard to discern in urban locales due to modern development. Most desa also are located close to a water source, such as a river or stream, where villagers traditional went to collect drinking and cooking water as well as
Wang et al. (1995) was one of the first studies to investigate a 1D model for morphodynamics that included a way to model bifurcations. They developed a nodal point relationship. This relationship was dependent on an exponent k, which could not be derived mathematically but had to be determined empirically. The model of Wang et al. (1995) was not very suitable for predictions of the evolution of a real bifurcation according to Pittaluga et al. (2003). The use of the k parameter, which has no relationship to any local conditions and therefore cannot be computed, proved to be the main problem. To overcome this, the nodal point conditions are reformulated by Pittaluga et al. (2003). A quasi two-dimensional scheme was introduced. This scheme is shown in Figure 2.2. Miori et al. (2006) has extended this model further by taking the eroding of banks into account. All three papers conclude their study with findings about the stability of a river bifurcation. The stability is not of interest for the present study.
The study site is located at the Lansheng Bridge on the Nan- shih River. Figure 2 shows the locations of the catchment area and gauge stations. Situated southeast of Taipei, Taiwan, the Nanshih River, an upstream branch of the Tanshui River, is a major fresh water source for the Taipei metropolitan area. To safeguard water quality and quantity, access to this area is restricted. Most of the area is thus untouched and forested. The area covers 331.6 km 2 and has an annual precipitation of 3082–4308 mm (average, 3600 mm). Days with precipitation are mostly concentrated in winter. The retreating monsoon produces fine rain in winter, whereas typhoons in summer bring heavy rains. The average monthly precipitation in the area from June to October exceeded 300 mm from 1992. Al- though a discharge measuring system that is composed of a radar sensor for measuring water stage and current meter for measuring velocity has been in place on the Lansheng Bridge since 2005, flood discharge was not measured until 2007. The average discharge of the Nanshih River at the Lansheng Bridge is 26.9 m 3 s −1 ; the minimum is 0.9 m 3 s −1 , and the maximum is 2295 m 3 s −1 . The Nanshih River is about 35 km long from its source to the Lansheng Bridge and 45 km to the confluence of the Nanshih River and the Beishih River; its highest altitude is 2101 m on Mount Babobkoozoo, and the altitude of the river bed at the Lansheng Bridge is 106.8 m. Thus the stream gradient, which is the grade measured by the ratio of drop in elevation of a stream per unit horizontal dis- tance, of the upstream of the Nanshih River exceeds 10 %, and the average stream gradient to the Lensheng Bridge is 5.7 %. The stream gradient at the study site is about 1.5 %, which is still relatively steep.
The treatment of the nonlinear friction term is key to find- ing an analytical solution for tidal hydrodynamics. The non- linearity of the friction term has two sources: the quadratic stream velocity in the numerator and the variable hydraulic radius in the denominator (Parker, 1991). The classical lin- earization of the friction term was first obtained by Lorentz (1926) who, disregarding the variable depth, equated the dis- sipation by the linear friction over the tidal cycle to that of the quadratic friction. An extension to include river dis- charge was provided by Dronkers (1964). In this seminal work, he derived a higher-order formulation using Cheby- shev polynomials, both with and without river discharge, re- sulting in a close correspondence with the quadratic velocity. Godin (1991, 1999) showed that quadratic velocity can be well approximated by using only the first- and third-order terms of the non-dimensional velocity. However, none of the above linearizations took into account the effect of the peri- odic variation of the hydraulic radius (to the power 4/3 in the Manning–Strickler formulation) in the denominator of the friction term. On the other hand, Savenije (1998), using the envelope method (see Appendix A), obtained a damping equation that takes account of both the quadratic velocity and the time-variable hydraulic radius in the denominator.
brings great added value in terms of automating water ecosystem management processes for national hydrology. To achieve this information system, the bibliographical knowledge of data management issues at hydrological stations allowed us to describe the process of acquiring river flows and to conduct systemic modelling of MERISE type leading to a national database on hydrometric stations, the rivers on which they are installed, daily measurements performed and the scale applied to each river. The tool put in place allows to track not only the flow of the Djiri River but also those of all the rivers of the Republic of Congo. The Djiri River data were used to simulate the tool and the analysis of this data reveals a decrease in flow over the entire period of 2017 and any season. This decrease in flow, characterized by a divergence index of 0.82344, highlights a hydrological situation for which national hydrology actors will absolutely have to implement remediation mechanisms to protect this against the possible disappearance.
The analysis of the variability of mean daily flow series ob- served along the Po River and some tributaries highlights the presence of local fluctuations of water scarcity and abun- dance that last for several years. They seem to be originated by perturbations whose memory is maintained in the long term. Likewise, statistical analyses confirm that the river flow series seem to be affected by long-term persistence, whose intensity increases for increasing catchment size. The above results show that the long-term behaviours of the Po River flows are not easily decipherable. Traditional methods for trend detection could be inadequate for interpreting patterns that seem to be far more complex than monotonic tendencies. In fact, the picture emerges of a hydrological system that is affected by local patterns that are likely to be related to natu- ral climate variability, even if one cannot exclude more com- plex interpretations that could refer to the intrinsic dynam- ics of the rainfall-runoff transformation. Similar phenomena were detected in other major rivers all over the world (Mon- tanari et al., 1997; Montanari, 2003; Grimaldi, 2004). The literature has not proposed a convincing physical explana- tion for such behaviours so far (Mudelsee, 2007). Yet, their implications in water resources management are potentially very relevant; inasmuch, they imply the above occurrence of long periods of water abundance and scarcity. These phe- nomena have been called “Noah Effect” and “Joseph Effect” by Mandelbrot and Wallis (1968).
pollutants, pollution level, and the source of the pollutants. These methods are considered conventional methods and have low resolution both in time and space. To overcome these limitations, a smart river monitoring system is proposed which combines the use of internet of things (IoT) and UAV. The use of IoT and data analytic have been recognized as an efficient way to monitor the WQ (Perumal et al, 2015; Pranata et al, 2017; Ranjbar & Abdalla et al, 2017) as compared to traditional methods where water samples are collected periodically for analysis purposes. However, due to the large span of area that needs to be monitored using UAV and IoT, the existing communication technology such as WiFi, Bluetooth, Zigbee and 3G are inadequate due to high power consumption and short range of communication. In addition, the use of fixed location sensors in river for collection of WQ parameters are affected by corrosion and marine substances. This reduces the accuracy of the measured data. Hence, we propose the smart river monitoring system (SRMS) that takes advantage of LPWA and UAV for remote monitoring. The proposed concept is discussed in detail in Section 3.
The extent of the benefits of improved river health remain uncertain. Quantifying these benefits is useful in prioritising policy investments. This study uses the Choice Modelling technique to estimate the value that households attach to attributes of improved river health. Data from a choice modelling survey supported by DSE Victoria are employed to elicit household preferences in a case study of the Goulburn River. Results from conditional and nested logit model specifications indicate that respondents hold positive values for higher levels of fish and bird populations and for increasing riverside vegetation. The standard Hausman test for Independence-from-Irrelevant- Alternatives (IIA) assumption violations is found to give inconsistent results. The value estimates of the conditional and nested logit models are shown to be statistically similar indicating that testing for IIA violation may be more complicated than currently assumed thus raising questions about the efficacy of the more complex nested logit model.
Land use in the Anacostia watershed today follows the general pattern of other metropolitan areas, with the most dense development concentrated near the urban center. The average imperviousness of the entire watershed is 22.5%. Nonpoint sources are the dominant form of pollution in the watershed, typically constituting 75 to 90% of the total pollutant loads to the river and its tributaries (Warner et al. 1996; Table 18.1). Between 80 and 90% of the annual nutrient loads (nitrogen and phosphorus) in the watershed are from nonpoint sources, with combined sewer overflows contributing a majority of the remainder. Eighty-five percent of the lead received by the river each year is believed to result from combined sewer overflow. Conversely, 85% of the annual zinc loadings is attributed to nonpoint sources. Additionally, the Anacostia receives approxi- mately 48,000 tons per year of total suspended solids, which on average equates to 0.44 tons per acre per year. Ninety-five percent of the total suspended solids loads originate from nonpoint sources such as construction activities, solids washed off of paved areas, and instream erosion of receiving channels in the form of bank erosion and substrate scour (Warner et al. 1996).
Over the past decades, the development of sediment transport mathematical models has been receiving more and more recognition, because they can be applied to assess the process of river bed evolution , . On the basis of the theories of overseas and domestic experts, the theoretical and applied researches of one-dimensional (1D) models are very mature, and the reliability and accuracy are good , , . The 1D model can analyze the general changes of flow and riverbed from a macroscopic view, but cannot simulate the local sediment movement in detail. Then the two-dimensional (2D) models are developed to simulate the refine local riverbed deformation and sediment deposition process in vertical and horizontal -. These models represent an improvement in the description of the sediment erosion and deposition in river system. However, as more and more water projects have been built, the abrupt changes of river flow-sediment conditions that influenced by the hydro-junctions are growing , . Then there is a need for a comprehensive modeling system that can realistically describe significant sediment erosion and deposition process. In the present study, the flow velocity, sediments discharge and bed-load gradation composition form the focus of the study, with which the transport of sediment and the thickness of erosion-sedimentation can be simulated by the developed 2D numerical model in river system. The model contains the hydrodynamic sub model, and the sedimentological sub model together with the bed deformation sub model. After calibration and validation, the model is applied to simulate the erosion and deposition process of sediment in the Three Gorges region. The results should provide a scientific basis for the improvement of the sediment management, which is the primary objective of the study.
1.2 Research Objectives
The objectives of this research are to: (1) develop a novel methodology to ap- proximate river cross section geometry for river networks where there is scarcity of river channel data, (2) link a Land Surface Hydrology model with a flow routing scheme, considering the lagging of the catchment runoff into the streams, to describe the flood wave of every reach within a particular river basin, (3) create the netlist, a syntax for river network topology using a set of defined blocks, for our study area, and (4) run the Simulation Program for River Networks (SPRNT) for the Guadalupe and San Antonio rivers basins and compare its results with measurements in selected stations from the United States Geological Survey (USGS). The initial difference be- tween the SPRNT simulations and the USGS streamflow stations measured data is used to calibrate the hydraulic routing model (Manning’s n).
Conclusion and recommendations results of data analysis of sulfate and heavy metals content in the leachate samples showed a relationship between sulfate content in the leachate sample and stream water sample. The pH of the leachate and stream water sample shows that the river was acidic. There was sulfate content in the stream water sample due to the complete weathering process of pyrite that leached sulfuric acid to water bodies