Jorma Koponen

• Environmental Impact Assessment Centre of Finland Ltd

Water infrastructure development is considered necessary to drive economic growth in the Mekong region of mainland Southeast Asia. Yet the current understanding of hydrological and flood pattern changes associated with infrastructural development still contains several knowledge gaps, such as the interactions between multiple drivers, which may hav...

Water infrastructure development is crucial for driving economic growth in the developing countries of the Mekong. Yet it may also alter existing hydrological and flood conditions, with serious implications for water management, agricultural production and ecosystem services, especially in the floodplain regions. Our current understanding of the hy...

The river flow regime and water resources are highly important for economic growths, flood security, and ecosystem dynamics in the Mekong basin – an important transboundary river basin in South East Asia. The river flow, although remains relatively unregulated, is expected to be increasingly perturbed by climate change and rapidly accelerating soci...

The Upper Mekong Basin is undergoing extensive hydropower development and its largest dams have recently become operational. Hydropower is built to improve the regional energy supply, but at the same time, it has considerable transboundary impacts on downstream discharge regime and further on aquatic ecosystems, riparian livelihoods and food securi...

Climate change poses critical threats to water-related safety and sustainability in the Mekong River basin. Hydrological impact signals from earlier Coupled Model Intercomparison Project phase 3 (CMIP3)-based assessments, however, are highly uncertain and largely ignore hydrological extremes. This paper provides one of the first hydrological impact...

Climate change poses critical threats to water related safety and sustainability in the Mekong River basin. Hydrological impact signals derived from CMIP3 climate change scenarios, however, are highly uncertain and largely ignore hydrological extremes. This paper provides one of the first hydrological impact assessments using the most recent CMIP5...

The Tonle Sap Lake of Cambodia is the largest freshwater body of Southeast Asia, forming an important part of the Mekong River system. The lake has an extremely productive ecosystem and operates as a natural floodwater reservoir for the lower Mekong Basin, offering flood protection and assuring the dry season flow to the Mekong Delta. In light of t...

The Tonle Sap is the largest lake in Southeast Asia and its fishery supports the livelihood and nutrition of millions of people in Cambodia. However, the hydrological and ecological drivers of this ecosystem are changing as a result of hydropower development on the Mekong River and global climate change. The objective of this study was to quantify...

The USAID Mekong ARCC project is a five-year project (2011-2016) funded by the USAID Regional Development Mission for Asia (RDMA) in Bangkok. The larger project focuses on identifying the environmental, economic, and social effects of climate change in the Lower Mekong Basin (LMB), and on assisting highly exposed and vulnerable rural populations in...

The Tonle Sap Lake in Cambodia is a dynamic flood-pulsed ecosystem that annually increases its surface area from roughly 2,500 km(2) to over 12,500 km(2) driven by seasonal flooding from the Mekong River. This flooding is thought to structure many of the critical ecological processes, including aquatic primary and secondary productivity. The lake a...

Freshwater biodiversity and ecosystem services are critically important to human wellbeing throughout the Lower Mekong River watershed and particularly so around the Tonle Sap Great Lake of Cambodia (hereafter the Tonle Sap Lake). Though seemingly lacustrine, the Tonle Sap Lake is actually an enormous wetland within a. (2012) A watershed moment for...

The Mekong River Basin in Southeast Asia is experiencing extensive hydropower development. Concerns have been raised about the consequences of the development for the ecosystems, livelihoods and food security in the region. The largest planned hydropower dam cascade in the basin, the Lancang-Jiang cascade, is currently under construction and alread...

Hydraulic erosion of bank toe materials is the dominant factor controlling the long-term rate of riverbank retreat. In principle, hydraulic bank erosion can be quantified using an excess shear stress model, but difficulties in estimating input parameters seriously inhibit the predictive accuracy of this approach. Herein a combination of analytical...

Riverbank erosion is a natural process, but often human activities can have a significant impact on the rates of morphological change. This paper aims to assess bank erosion problems in the Vientiane–Nong Khai section of the Mekong River, where the Mekong borders Thailand and Lao PDR. The study provides new and more accurate information about recen...

It has been claimed that Tonle Sap Lake is rapidly filling with sediment as a result of increasing sediment yields from the catchment. Infilling of the lake basin would have serious implications for the magnitude of flooding in central Cambodia and the Mekong Delta region and threaten the lake's unique ecosystem. In this article, we synthesize the...

Tonle Sap Lake is a large and complex data-deficient ecosystem in the Mekong River Basin. Highly valuable in biodiversity and natural livelihoods capital, it is susceptible to degradation when the flood pulse that drives its productivity is altered as a result of hydropower and irrigation development on the Mekong River. To date, there are no tools...

River bank erosion is the product of a suite of specific processes that together contribute significantly to the sediment yielded from river catchments. Many studies have emphasised that hydraulic erosion of bank-toe materials may exert a dominant influence on the long term rate of river bank retreat. Fluvial bank erosion rates are normally quantif...

Are models useful for management and decision making on water resources? Are the efforts put into them justified? In this chapter we argue that mathematical modeling is one of the few options available to look at the questions of future changes and impacts of human activity on water resources. Models and their results, however, are often mistrusted...

The ecosystem of the Tonle Sap Lake is driven by the monsoon floods of the Mekong River. This unique pulsing system together with high annual sediment and nutrient fluxes from Mekong makes the Tonle Sap one of the most productive freshwater ecosystem in the world. However, local and upstream developments have increase the environmental pressure and...

Integrated Water Resources Management has been identified as one of the basic water resources related policy approaches in several recent important commitments and recommendations including the Johannesburg Summit and World Water Forums. Recognizing that IWRM is largely still a theoretical concept with not much sound scientific research, our object...

The ecosystem of the Gulf of Finland is currently dominated by internal phosphorus loading from sediments. The internal load is highly redox sensitive, and its successful modelling on basin-wide scale requires a simplified description of the sediment process. We present here an approach in which redox-sensitive sediment processes are directly linke...

Abu-Qir Bay is a semicircular basin in the eastern part of Alexandria City, Egypt. The Bay has a maximum depth of 15 m, and surface area of 500 km2. The bay is suffering from a serious pollution problem caused by the inflow of brackish water from Lake Edku and the poor-quality water discharged from the Rosetta Nile branch. The variations in wind re...

A hydrodynamic and water quality model were applied to a coastal bay east of Alexandria City in the southeastern sector of the Mediterranean Sea subjected to industrial, agricultural and sewage discharge to determine the transport and dispersion of Total Lead (PbTOT) and Dissolved/Dispersed Petroleum Hydrocarbon (DDPH). The water circulation in the...

Sbornik tezisov : VI Mezdunarodnogo ékologiceskogo foruma "Den baltijskogo morja" [21-23 marta 2005 g. Sankt-Peterburg]. Sankt-Peterburg, Baltic Marine Environment Protection Commission - Helsinki Commission (HELCOM). C. 77, 79. VI Mezdunarodnogo ékologiceskogo foruma "Den baltijskogo morja", 21-23 marta 2005 g. Sankt-Peterburg

Tonle Sap Lake in Cambodia is the largest permanent freshwater body in South-east Asia. The 3D hydrodynamic and water quality model has been set up for the lake and its floodplains to understand the ecosystem and geomorphological processes, and the possible changes caused by the Mekong upstream developments as dams and reser-voirs.

Helsinki is located on the southern coast of Finland by the Baltic Sea. The ecological state of the archipelago in front of Helsinki is affected by several factors. The effects of local point and scattered loads are mixed with the transboundary effects from neighbouring countries and atmospheric deposition. Municipal waste waters of 800 000 inhabit...

Figure 1. Lower Mekong Basin with Tonle Sap Lake. Dry season lake (~1.5 m above the mean sea level (a.m.s.l.)) is presented as dark blue while the flood plain of the year 2000 flood is presented as lighter blue (~10.3 m a.m.s.l.). The 2-year project "Modelling of the Flow Regime and Water Quality of the Tonle Sap" (MRCS/WUP-FIN) has helped the MRC...

The Gulf of Finland is one of the most eutrophied areas of the Baltic Sea. The major part of the nutrient load enters the sea outside Finnish borders from the metropolis of St. Petersburg and the river Neva. Finnish local authorities are facing a difficult task of defining water protection measures, when the effects of local measures have to be wei...

Based on a model of light limited growth, Huisman and Weissing found that in a well mixed water column with constant light supply (energy reaching the water surface), equilibrium growth and competition of phytoplankton for light can be characterised by a critical light intensity at the base of the column (I*out). The present study attempts to give...

Nutrient concentrations have increased in the Archipelago Sea during recent years. This is probably caused by growth in the loads from agriculture, air, fish farming and the Baltic proper. The Archipelago Sea acts like a nutrient filter between the Baltic proper and the Bothnian Sea; part of some of the externally input nutrients are retained withi...

The three-dimensional water quality and flow model was used to simulate phytoplankton biomass and dissolved nutrient concentrations in the Gulf of Finland. In the model, transport of nutrients is based on calculated wind and river flow-induced currents. Water quality data from two points off the Finnish coast were used for the model calibration.Nit...

Environmental Modelling & Software, 1364-8152, vol. 13, nr. 5-6 , 503-509 One of the most visible symptoms of eutrophication in the Gulf of Finland is blooms of unattached filamentous algae. This decomposing algal biomass causes serious nuisance problems for recreational uses of the coastal zone, particularly when cast ashore. The nutrient availabi...

Three-dimensional (3D) numerical models were developed for the circulation, water quality and bottom dynamics of reservoirs. Reservoir models were further completed with calculations of river sections, lake, coastal area and the sea downstream of a planned reservoir, Vuotos, in Finnish Lapland. As the main effects of Vuotos, phosphorus load is expe...

The validity of complex three-dimensional reservoir models has been tested in three lines: 1. by comparing the model results with observations of the existing reservoirs and the downstream water course under the real conditions in 1971-1992; 2. by comparing the model results with detailed laboratory and field measurements specially designed to test...

An automatic monitoring system has been developed for continuous monitoring of water quality along water course. The system consists of automatic gauges for measuring water quality, numerical models of the water course for developing of the water quality and user interface for systems management. The measured results are recorded to the computer of...

During the summers of 1989–1990, the pattern of water flow and the water quality in Lake Pyhselk, Finland, were studied using field observations and a 3-dimensional model. The lake receives its major point-source loading, including pulp mill effluents, via the Pielisjoki River in the northeastern part of the lake, where the water is slightly eutrop...

Boreal environment research, 1239-6095, vol. 1, nr. 1, 27-35 A resuspension model was added to a 3D flow and water quality model. The resuspension model consisted of a wind-wave model, an orbital current model and an erosion model. Erosion was modelled using the critical current velocity. The wave induced orbital current was added to the advection...

A model system has been generated for the buttom and water quality development of reservoirs during the first few decades of impounding. The model is based on 3D (three-dimensional: longitude × latitude × depth) calculation of the water currents, their variation with time and on 3D description of release, transport, degradation, settling and other...

Three-dimensional (3-D) mathematical models of water currents, transport, mixing, reaction kinetic, and interactions with bottom and air have been used in Finland regularly since 1982 and applied to about 40 cases in large lakes, inland seas and their coastal waters. In each case, model validity has been carefully tested with available flow velocit...

Aqua Fennica, ISSN 0356-7133, vol. 23, nr. 2, 117-124 A short history of mathematical flow and water quality modeling in Finland is presented. Results from the Bothnian Bay research project are reviewed. They include international inquiry about model development and use, flow and water quality measurements, model verification, simulation of Bothnia...

Aqua Fennica, ISSN 0356-7133, vol. 23, nr. 2, 259-269 Local studies of coastal areas are of central interest for seas, because most of the activities, loads and observations, and the most obvious effects are typically concentrated on the areas near the coasts. Improved understanding of the importance of the exchange dynamics between the coastal zon...

Systems Analysis Applications to Water Research - A Soviet-Finnish Project. Ed. Timo Huttula. Publ. Water and Environment Research Institute No. 3, 55 - 61

Nord. Hydrological Conf., NHK -88. Rovaniemi, 1. - 3.8.1988

An ecological model, coupled with a hydrodynamic one, is applied to Lake Näsiselkä, the southernmost sub-basin of Lake Näsijärvi, Central Finland. Its surface area is 93 km2, mean depth 15 m, maximum depth 61 m, and through-flow 64 m3/s. The transport velocities to the ecological model are computed with a three-dimensional hydrodynamic sub-model. I...

Aqua Fennica Vol.15 Nr.1, 118 - 124

The Tonle Sap Lake and floodplains in the heart of Cambodia contain the largest continuous areas of natural wetlands habitats remaining in the Mekong system, while being the largest permanent freshwater body in Southeast Asia. Tonle Sap is a crucially important source for food and living in Cambodia. More than one million people live in the immedia...

Natural resources are vital to people along the Mekong as the livelihood of most of the people depend to large extent on natural ecosystems, especially in the poorest countries Cambodia and Lao PDR. One of the most important parts of the Mekong system is the Tonle Sap Lake in Cambodia being the main source of animal protein for Cambodia and working...

The Tonle Sap Lake (known also as the Great Lake), located in central Cambodia, is the largest freshwater lake in Southeast Asia and an important component in the Mekong River system. The area is globally unique and the lake has an extraordinary hydrological system. The importance of the Tonle Sap Lake goes far beyond provincial and even national b...

Biotieteen päivät. Publications of the University of Kuopio. Abstract, 13

4th Int. Conf. on State-of-the-Art in ecological modelling. Tsukuba, Ibaraki, Japan, 20 - 24 Aug. 1984

Publications of the University of Kuopio. Abstract. Biotieteen päivät. Kuopio 1984, BL19

Physical Processes in Lakes. Lammi, 21 - 24 April 1986

Proc. Nord. Semin. Physical Processes in Lakes. Lammi, 21 - 24 April 1986

Symp. Baltic Marine Biology. Kiel, 29 Sept. - 3 Oct. 1987

NHP-Report No. 16. Physical Processes of Lakes (Ed. J. Virta), 71 - 83

OECD Chemicals Group and Management Group Committee, OECD Draft Compendium of Environmental Exposure Assessment Methods for Chemicals, OECD/ OCDE ENV/CHEM/HAP 88.1., 217.1 - 7

Koordinationskommitteen för Hydrologi i Norden, KOHYNO. NHP-Report No. 22, 327 - 340

Vesitalous Vol.30 Nr.5, 19 - 21

OECD Compendium of Environmental Exposure Assessment Methods for Chemicals. Environment Monographs, No. 27, 139 - 146

Est.-Finn.-Sov. Water Res. Symp. Ongu, Hiiumaa, Estonia, 12 - 14 Sept. 1989

Vesitalous, ISSN 0505-3838, vol. 30, nr. 5, 19-21 Metsäteollisuuden vesiensuojelu : Oulun vesistötutkimuspäivät Oulu 1989

Aqua Fennica, ISSN 0356-7133, vol. 23, 251-258 During 1990-1992 operational models were developed for Finnish sea areas to estimate the transport, spreading and fate of oils and chemicals released during accidents. The possibility to calculate the transport of vessels at distress was also added to the models for use under sea rescue operations. The...

Hirvi, Juha-Pekka (ed.) Operatiivinen ajelehtimis- ja kulkeutumismalli merialueille, Vesi- ja ympäristöhallinnon julkaisuja - sarja A ; 134, 15-24 The 3D-model is sc. big model including seven functional units and 40 000 programlines. The model will be used in serious accidents at sea, eg. disapparance of people, spillage of hazardous chemicaals, o...

Hirvi, Juha-Pekka (ed.) Operatiivinen ajelehtimis- ja kulkeutumismalli merialueille, Vesi- ja ympäristöhallinnon julkaisuja - sarja A ; 134, 25-33 3D-model's PC-version (3D-PC) has been developed and implemented to the the coastal sea areas. The 3D-PC is intended for local use by combatting authorities. Transport calculation is based on set of stat...

Hirvi, Juha-Pekka (ed.) Operatiivinen ajelehtimis- ja kulkeutumismalli merialueille, Vesi- ja ympäristöhallinnon julkaisuja - sarja A ; 134, 57-68 The development work started in 1991 by making two different literature studies on modeling and behaviour of organic chemicals in sea water. A prototype of the chemical module was developed and installed...

Hirvi, Juha-Pekka (ed.) Operatiivinen ajelehtimis- ja kulkeutumismalli merialueille, Vesi- ja ympäristöhallinnon julkaisuja - sarja A ; 134, 67-76 Wind data input for the operational §D-model are obtained from the High Resolution Limited Area Model (HIRLAM). This model is at the moment the most consistent source of wind information. The Finnish met...

Hirvi, Juha-Pekka (ed.) Operatiivinen ajelehtimis- ja kulkeutumismalli merialueille, Vesi- ja ympäristöhallinnon julkaisuja - sarja A 134, ISSN 0786-9592, 77-93 The data from drifting tests, current measurements, oil combatting exercises and well documented sea accidents was used for testing, calibration and to compare the models. The results and e...

Hirvi, Juha-Pekka (ed.) Operatiivinen ajelehtimis- ja kulkeutumismalli merialueille, Vesi- ja ympäristöhallinnon julkaisuja - sarja A 134, ISSN 0786-9592, 95-104 The operational use of the models focuses to special situations, for instance: 1. people and life boats floating at sea 2. major oil spills, sinking or drifting chemicals (floating or soli...

Proc. of the Int. Conf. on oil terminals, shipping and off - shore activities in the eastern Baltic, Tallinn, 90-91

Tr.: Sgornik tezisov : VI Mezdunarodnogo ékologiceskogo foruma "Den baltijskogo morja" [21-23 marta 2005 g. Sankt-Peterburg]. Sankt-Peterburg, Baltic Marine Environment Protection Commission - Helsinki Commission (HELCOM). C. 72, 74, 76. VI Mezdunarodnogo ékologiceskogo foruma "Den baltijskogo morja", 21-23 marta 2005 g. Sankt-Peterburg

Tr.: Sgornik tezisov : VI Mezdunarodnogo ékologiceskogo foruma "Den baltijskogo morja" [21-23 marta 2005 g. Sankt-Peterburg]. Sankt-Peterburg, Baltic Marine Environment Protection Commission - Helsinki Commission (HELCOM). C. 73, 75. VI Mezdunarodnogo ékologiceskogo foruma "Den baltijskogo morja", 21-23 marta 2005 g. Sankt-Peterburg

Tr.: Sgornik tezisov : VI Mezdunarodnogo ékologiceskogo foruma "Den baltijskogo morja" [21-23 marta 2005 g. Sankt-Peterburg]. Sankt-Peterburg, Baltic Marine Environment Protection Commission - Helsinki Commission (HELCOM). C. 76, 78. VI Mezdunarodnogo ékologiceskogo foruma "Den baltijskogo morja", 21-23 marta 2005 g. Sankt-Peterburg

In: IMEMS 2005 : The 8th International Marine Environmental Modeling Seminar. Helsinki, Finland, 23-25 August, 2005. Abstract Proceedings. [Helsinki], SINTEF, SYKE. P. 9. IMEMS 2005 : The 8th International Marine Environmental Modeling Seminar. Helsinki, Finland, 23-25 August, 2005

Publications of the Water and Environment Research Institute, 0783-9472 ; 7 Pages: 91 s. The dynamics of the Bothnian Bay was studied mainly by means of numerical models. The model results were supported by flow velocity measurements and by water quality components sampled for more than twenty years in the research area. Prior to the study an exten...