Consequences of dams on the Mekong river

Consequences of dams on the Mekong river

For fisheries along the Tonlé Sap river and Lake floodplain

ABSTRACT - This research focuses on the Tonlé Sap river in Cambodia. The Tonlé Sap river is one of the most productive freshwater fisheries, but due to hydropower developments on the nearby Mekong river, these ecosystems are under threat. This paper examined the increasing dams on the Mekong river and its impacts on the local fisheries along the Tonlé Sap river. It gives an elaborate theoretical framework based on a literature study on the interrelationships between dams, sedimentation, fish migratory and reproduction patterns and access to fishery. Also the relation with management and industry is explained. It was found that dams negatively influence sediment load/nutrient load and negatively affect migratory patterns of fish species in the area as well. Finally, this relationship negatively affects the fish stock and access towards the fish stock.

Course: Interdisciplinary Project

Students: Sanne Valentijn (11856866), Amber Cok (11629258), Rebecca van Oostveen (11862858), Eva van Doore (11811110), Rick van Beek (11885300)

Supervisor: Andres Verzijl Tutor: Vikki de Jong Date: 4-12-2019 Words:

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Content

5. Selected method and data 9

6. Results 11

7. Conclusion and discussion 16

8. Recommendations 16

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1. Introduction

The Tonlé Sap lake is located in Cambodia, within the floodplain of the Mekong river. The Mekong river is subject to a periodic pattern of floods, that connects and disconnects the river with the Tonlé Sap lake (Lamberts, 2008). The water levels of the Mekong river vary up to approximately 8 meters throughout the year. After numerous fluctuations, the water levels rise above a certain threshold level and the water flows into the Tonlé Sap river and lake. This usually happens around late May, and lasts

for about 5 months (Lamberts, 2008).

Thanks to these periodic floods, the Tonlé Sap lake and river is considered to be one of the most productive freshwater ecosystems in the world. The fluctuations causing the flood pulse dynamic are responsible for the high productivity, with the annual fish catch from the lake estimated to be around 18.000-250.000 tonnes (Koponen, Kummu, & Sarkkula, 2005). The majority of the surrounding population of the Tonlé Sap lake and river ecosystem depends on food supplies gained from fishery and agriculture (Hartmann, 2018; Teh et al., 2019; Dina & Sato, 2014). To ensure these food supplies, the local population depends on the water body of the Tonlé Sap river. This river is therefore a crucial component for the fish capture and accordingly also important for the well-being of the local population. In 2008, about 40% of the population lived below the poverty line (Nikula, 2008). In the period thereafter, the country experienced accelerated economic growth and in 2014, the poverty rate decreased to 14% (Hartmann, 2018). Due to new upcoming technologies and this decreasing population that lives behind the poverty line, Cambodia needs new energy sources to sustain this economic growth. Currently, the Mekong river basin is undergoing massive hydropower development, with plans to build multiple large dams. With its dependence on these sources and the interest for green energy growing, dam-developments have been increasing rapidly during the last decade (Lu et al., 2006). King et al., (2007) identified 92 dams on the Mekong river to be either planned or already under construction. Furthermore, plans have arisen the last couple of years for even bigger and larger dams (Dugan et al., 2010).

An increase in hydropower dams on the lower Mekong river is therefore likely to happen. These constructions that influence the currents of the Mekong river will subsequently influence the Tonlé Sap river as well. However, concerns for the consequences these dams might have, are frequently overlooked. From a hydrological point of view, the water flow regime, sedimentation accumulation and transport of this Mekong river will drastically change with the implementation of (a) large dam(s) on the lower Mekong river in Cambodia (Ziegler et al., 2013). Furthermore, fish reproduction will alter due to changes in migration patterns, having an effect on the fish population and thus the fishing industry as well (Lamberts, 2008). The surrounding population of the Tonlé Sap region highly depends on fish for food security and economic well-being (Hartmann, 2018). A reduction in the fish population will cause drastic changes in the livelihood of these people.

Since the implementation of these dams could have a significant impact on the area, this research will focus on the question “How does an increase in dams on the Mekong river impact the ecosystem and local fisheries along the Tonlé Sap river?”. This question will be answered using four different disciplines, namely biology, governance, business administration and earth sciences. Knowledge from these disciplines will be integrated and linked to each other, which will create an interdisciplinary insight into this problem. Moreover, integrating will provide insights on the eco-hydrogeomorphological part of the concerns and the societal problems that arise. This is helpful in assessing the problem and to gain a cohesive understanding of the problem.

In addition, the results of this research will play a vital role in understanding the consequences a dam has on the area of the Tonlé Sap lake, which is especially relevant for the local community. A primary concern for the local community living around the Tonlé Sap river is how they will sustain

4 their current lifestyle when changes (i.e. hydropower development projects) are carried out. This research will provide a clear view on how ecological changes combined with social governance influences the habitat of species and citizens living near the Tonlé Sap lake and river. To provide an answer to the research question, first a theoretical framework is provided. In this theoretical framework, a clear overview of the problem area is given. In addition, the differentiation of the concepts related to dam implementation are distinguished to clarify the impacts. Then a problem definition is given to state the research problem. After this, the interdisciplinary integration follows, explaining which integration technique is used and how. This is followed by selected method and data section. This section will explain how the literature about the impacts of the dam on the environment will be used as a support for the access- and market analysis, which consists of a Porter's five forces analysis and an additional SWOT analysis. Then the results section will explain how the environment is affected by the implementation of the possible dams. Furthermore, it will combine the before mentioned analyses and will search for new insights into how the local fisheries is affected by the negative environmental impacts caused by the dam. Lastly a conclusion, a discussion and recommendations will be given.

2. Theoretical framework

This chapter consists of a framework with disciplinary insights. In this section concepts and theories will be discussed and explained according to figure 1. This figure shows the most important concepts in this case study. The aim is to provide background information on these concepts and how they are related. In addition, figure 1 shows that all concepts lead to fish production which are, as discussed in the introduction, a crucial component for the local population. To get a better understanding of how dams will influence the fish production and therefore the local population, it is crucial that these concepts are well understood.

Figure 1. Most important concepts and theories relating to the fish stock within the Mekong river and Tonlé Sap river including positive (+) and negative (-) correlations.

2.1 The concepts influencing fish stock

Several factors are essential for the high productivity of the Tonlé Sap lake, three of these are discussed in figure 1. This figure is structured as follows: sedimentation, migration and reproduction are the three most important components leading to the growth of fish. The fish growth increases the

5 fish stock, which leads to more fish available for fishing. Consequently, this ensures the local population of food security in the form of fish. The access to fish will play a vital part in the well-being of the local fishing companies. Especially for the small family sized fisheries, who are the biggest and most important group in terms of catch and total revenue (Teh et al., 2019; FAO 2011). Approximately 30-40% of the fish caught by family sized fisheries is used for home consumption, the rest of the catch is directly sold on local markets (Teh et al., 2019; Drammeh, 2000). Because these local markets are of great importance for the economic well-being of the local population and constitute the highest part of the fishing industry, the focus of this research will be on family-scale fisheries and will only be referred to.

The Tonlé Sap ecosystem in Cambodia is a large segment of the Mekong basin. This basin consists of the Tonlé Sap river and lake and their surrounding floodplains. The connection between the Tonlé Sap lake and the Mekong river consists of a 100 km long tributary of the Tonlé Sap river. This river is the part of the basin that receives the floodwater from the Mekong river, subsequently increasing the volume of the Tonlé Sap lake from about 1.3 km3 to 50-80 km3 depending on the flood intensity (Lamberts, 2008). These water fluctuations, and the flood-pulse interactions that come with it, play a significant role in the exchange of sediments, nutrients and organisms from the separate water bodies (Cochrane et al., 2016; Olson & Morton, 2018). According to Lamberts (2008), flood pulse is defined as the term for an ecological paradigm that integrates the processes of productivity in river-floodplain ecosystems.

This flooding of the Mekong river into the Tonlé Sap lake leads to several processes. Firstly, the high velocities of water will lead to large amounts of sediment in the Tonlé Sap river: A river can be seen as a stream of water consisting of flowing sediments. Sediment will naturally flow within a river and is to be transported by the stream in the water. In the Tonlé Sap river, the diversity in fish species is generally higher in transitional zones between the Tonlé Sap lake and the Mekong river. This diversity is especially high during a period of migration. Research done by Lim et al. (1999) provides an explanation for this phenomenon. The answer lies within the ecotone. An ecotone describes an area that acts as a transitional site between two ecosystems (Lim et al., 1999). This specific ecotone between the two water bodies provides food and cover for specific fauna, but more importantly acts as a habitat for many rare or endemic species that were specifically adapted to the flood-pulse system (Lim et al., 1999). When the flooding season starts and large terrestrial habitats are flooded, large amounts of inorganic and organic matter that were deposited are mobilised by the overlaying water. This process causes large amounts of nutrients within sediments and energy to be transferred into the water. Fish actively seek out these highly active areas during the flooding season, causing mass migrations (Lamberts, 2009).

Secondly, the velocities induced by the flood-pulses also attribute directly to these fish migrations. Many fish species in the Mekong river are migratory, in total they contribute 48% of the total fisheries in the area. These migratory fish move between the different water bodies depending on their reproductive stage. Different fish species have different migration strategies, with some species migrating only within the Upper Mekong and others migrating great distances along the entire Mekong basin (Kang et al., 2009).

Most fish species migrate upstream during the rainy season to arrive at their spawning grounds (Lim et al., 1999). A study done by Baran, Starr & Kura (2007) shows that the Tonlé Sap lake is home to almost 300 species, making it the third-richest lake in the world in terms of fish diversity. The Tonlé Sap lake is an important area consisting of spawning grounds for these species (Bond, 2015). Spawning grounds are essential for the fish reproduction and are thus one of the reproductive requirements. The described flood-pulses are an important factor leading to the formation of spawning grounds because these high flow velocities induce the recruitment of spawning gravel at the areas where it is necessary (Ligon, Dietrich, & Trush, 1995).

6 Fish migration plays a crucial role in the life cycle of many fish species, and it depends on the flow directions and the quality of water (Lamberts, 2008). In summary, the flooding contributes to fish reproduction and migration and therefore to the growth of the fish stock, as shown in figure 1. The flood-pulse dynamic is thus important, since it supports the freshwater fish community and maintains the diversity in fish species (Pool et al., 2017).

In addition to the migration and spawning grounds, more reproductive requirements are necessary for optimal fish breeding. Flow, and especially the temperature are variables which are important determinants of spawning for many fish species. They ensure the timing and strength of fish spawning (King et al., 2016). As stated earlier, the water flow caused by flood pulses enhances the fish spawning and recruitment. Flow is also an important factor influencing the key aspects of the fish life cycle, such as the cue for movement and reproduction, egg survival and the improvement of the survival of larval and juvenile (King et al., 2016).

Moreover, an optimal temperature is required for fish reproduction. King et al., (2016) states that fish species utilize an optimum temperature for maximum spawning. Temperature can act as a cue for the migration by which higher surface temperatures lead to earlier migration of some species to their spawning grounds. Temperature-dependent species migrate, and thus, spawn earlier in warmer years. However, not all fish species experience a change in migration due to altered temperatures (Sims et al., 2004).

2.2 The difficulty of water regulation and the concept of access

A growth in the fish stock is important for the surrounding local populations and their fishing companies (Hartmann, 2018). Figure 1 shows this positive relation between the fish stock and fishing. However, before fishing can take place, it is required that the local fisheries have access to the fish stock fisheries. This paragraph will explain water regulation and therefore access to fish.

About 64% of the rural households earn their living by fishing (Teh et al., 2019). With a total revenue of over $2 billion USD, the fishing industry is the most important economic driver of this region (FAO 2001; Hartmann, 2018). Tonlé Saps fishing industry accounts for two-thirds of the total fish catch in Cambodia (Baran, Starr & Kura, 2007). As mentioned before, approximately 30-40% of the caught fish is used for home consumption and the rest of the catch is directly sold on local markets (Teh et al., 2019; Drammeh, 2000). Especially the family-scale and rice field fishing segment of the industry is considerably more important than the middle and large scale fishing companies (FAO, 2011; Teh et al., 2019). Therefore, the amount of available fish is crucial for the surrounding families and industries of the Tonlé Sap region.

Since Cambodia's economy is rapidly developing, it could be predicted that the demand for animal products will increase as it generally does as countries are becoming wealthier (FAO, 2006). And due to the law of demand and supply it is likely that the pressure on fish populations will increase because of more extensive fishing.

Water rights are more difficult to regulate than land rights (Gupta, 2013). One of the major reasons is that water is movable. In most cases, it flows through multiple countries and has to be shared by them. The sharing countries will have to negotiate in order to get a fair distribution of water. Cambodia is an example of a downstream country, and will therefore experience more problems due to changes (e.g. dams or polluting industries) made by upstream countries (Gupta, 2013). Economic prosperity and local environmental circumstances are others factors that lead to different regulations of water. Some countries surrounding the same river are economically wealthier than others, which gives them more options for water regulations. Due to differences in economic prosperity, political infrastrures and different local environments, water has to be regulated on multiple scales (Gupta, 2013). This is a component that makes water government complicated and, above all, it requires the involvement of multiple actors who influence the access to water.

7 This complication can even lead to various legal systems and legislative frameworks that exist simultaneously: legal pluralism, a lack of clarity in the rules due to multiple regulations on different scales (Franco et al., 2013; Suhardiman & Giordano, 2014). This lack of clarity can make it difficult to determine who or which group has legitimate access to the source (Gupta, 2013). Although in this case study the concept of legal pluralism is important to be highlighted, because the local situations in Cambodia differ in terms of regulations (Werthmann, 2010), it will not be discussed in further detail. What is important to realize is that legal pluralism influences the structure of water governance because it is hard to know the difference between which actors are participating and which actors should be participating in the decision-process (Franco et al., 2013). This can cause an asymmetric power distribution in which some groups will conceive more access rights than others. Larger fishery companies, for example, have more tools to catch fish than small scale family fisheries because they have a smaller capital. Larger companies can afford expensive and better fishing nets, which will give them the power to catch more fish when the source gets scarce than poorer fisheries who have fewer tools at their disposal. This inequality makes water governance unstable because some actors have more tools to gain access through possession.

2.3 Dam related concepts

After the implementation of dams, most of the described concepts will alter. There are several concepts involved in this implementation, which will be discussed in this paragraph to clarify the later discussed results.

Petts (1980) distinguishes two ways in which river alterations by dam-developments (or: reservoir implementation) influences the river dynamics. The first one is that the flow regime of a river is altered after such a construction. The second reason why the building of the dam would be problematic is the interception of sediments by reservoirs, or in this case dams (Petts, 1980) The interception of sediments by reservoirs or dams is called the process of sediment accumulation. Sediment will naturally flow within a river and is to be transported by the stream in the water. Once a dam is constructed, a large portion of this water is captured and therefore the sediments. In this dam reservoir boulders, pebbles, sand and silt accumulate within it. The term Sediment Trap Efficiency (TE) describes the inflow of sedimentation of the river that is permanently captured by a dam (McCully, 1996). When sediments are intercepted by a dam, this not only means that they accumulate within the dam, but those sediments will therefore not be transported further on in the river. If sediment transport of a river is interrupted, it is possible that a river continues to consist of hungry water (Kondolf, 1997).

Hungry water refers to water that is deprived of its sediments and becomes sediment-starved water. If

a river consists of hungry water this can have major implications for a systems ecosystem. Not only due to the alteration of water quality, but also for the habitats that are dependent on the ecosystem functioning (Lu, Kummu & Oeurng, 2014). Sediment hungry rivers influence several factors. Wang et al. (2011) mentions the aquatic environment and fisheries to be largely influenced by flow alterations. Baran et al. (2015) explains in their research that when rivers lack of sediments in their fluvial regimes the fish population is directly affected by this, due to the storage of nutrients within sediments. Nutrients, such as Phosphorus and Nitrogen, are needed for fish growth and existence (Baran, Guarin & Naielski, 2015). So when aquatic systems become sediment deprived, fish populations and local fisheries are directly affected by such an occurrence. This will put more economic pressure on small scale fisheries.

It is expected that the implementation of the dam will have some negative impacts on the fish population. To identify how this degradation of the fish population influences the local fishing industry, a market analysis can be conducted in the form of a Porter’s five forces analysis and an additional SWOT analysis. The Porter's 5 forces analysis can be used to expose industry strengths, threats and weaknesses (Volberda et. al., 2011). The strengths and weaknesses could be used to come to a fitting

8 policy. Porter's 5 forces analysis consist of 5 forces: (I) threat of new entrants, (II) bargaining power of suppliers, (III) bargaining power of consumers, (IV) substitute products and (V) rivalry among competition. These could be used for an industry broad analysis, in terms of competition and attractiveness of the industry. The information that is gathered in the five force analysis together with additional literature could be used to make a Strengths, Weaknesses, Opportunities, and Threats SWOT analysis. A SWOT analysis is a tool that has been invented by Albert Humphrey (2005) to analyse and expose an industry's strengths, weaknesses, opportunities and threats. A SWOT analysis is performed by identifying the I) organisational strengths II) organisational weaknesses III) environmental opportunities and IV) environmental threats (Gürel, 2017).

Furthermore, this caused degradation of the fish population will make access to fish more difficult for the local population. The influenced access and the impacts on the fish population will be further explained in detail in the results. With the water governance perspective, this issue of access will be discussed in more detail with an access analysis, described by Ribot (2003). This analysis is a process to identify and map access mechanisms. A further explanation will follow in the method section. To do a clear access analysis, it is important to define the content of how access is defined first. According to Ribot (2003), there is a significant difference between access and property rights. Ribot (2003) defines access as the ability to profit from a resource (e.g. an institution, person or object).

Property rights are similar to access rights, but it lacks the part which gives a person or group the actual

ability to profit from the resource. This implies that it is possible to have property rights, without having actual access to the resource (Ribot, 2003). For example, the property right could be the right to fish in the Tonlé Sap river, but when these fish disappear, access to this source will be harder to reach or will be lost. With this insight, the building of the new dams are not a potential threat to property rights, but to access. An in-depth understanding of these concepts applied to water is required to develop an equitable and legitimate governance system (Gupta, 2013), wherein the local, Cambodian fisheries are able to use the source of fish.

3. Problem Definition

During the literature research about the problem area, several problems were encountered as well as numerous theories and insights. This section discusses these theories and insights, which lead to our problem definition.

Literature indicates that the existing dam constructions already have had negative impacts on fish populations. Further negative predictions have been made for upcoming dams in the Lower Mekong river concerning the Tonlé Sap river. Once a dam is installed, it can have an impact on sedimentation and flow direction. It is important to define if that is the case in the Lower Mekong river, because these changes in sedimentation and flow direction may influence fish species in the river. In addition, the introduction of dams could have damaging effects on the ecosystems by altering the flood pulses and

thus the migration of fish and the fish spawning.

When it comes to fish it is important to realise how the fish industry is governed along the Tonlé Sap river and what the impact of water governance is in the local villages. Moreover, how will business and fishing industry be affected by a dam and how can local citizens prepare and mitigate? Information on this subject integrated with ecology is now lacking. These questions combined make our research question: “How does an increase in dams on the Mekong river impact the ecosystem and local fisheries along the Tonlé Sap river?”. This will be researched by interdisciplinary research. In this research insights from the different disciplines will together answer this question, because implementation of new Dams on the Mekong river will have both have impacts on an ecological and a sociological level. This is also why this is problem is such a complex one. Political decisions and social structures influence

9 the functioning of the ecosystem, while the ecosystem is crucial for the well-being of the local population.

4. Interdisciplinary integration

According to Newell (2006), there is a variety of integrative techniques that can be categorized into three broader classes of integration methods for interdisciplinary research. In this research, a combination of these three techniques was used. In the following section of this paper these techniques will be explained and the implementation of them will be illustrated.

The first technique entails that one or more elements from another discipline can be added to a certain disciplinary theory. Many concepts and theories used in this paper had a meaning that could be extended by the means of another discipline. An example of this is the term flood-pulse. This concept is defined in existing literature as the term for an ecological paradigm that integrates the processes of productivity in river-floodplain ecosystems. In this research, however, the term was used in the dynamics of nutrient flow, migration, and the effect on reproduction. A biological term that was used to express productivity is now included in multiple processes within the river-floodplain dynamics. The second technique involves the adjustment of disciplinary theories using insights from different disciplines. This technique was used while creating the theoretical framework as well.

The final technique involves connecting several disciplines around a central idea. This technique is used most frequently in this research, as it is the backbone of the entire theoretical framework. In figure 1, the central idea of this theoretical framework is visualised. The image can be seen as an assembly of individual components that are interlinked in a larger process, in this case the dynamics of the fish population in the Tonlé Sap lake. Components from the four disciplines (earth sciences, biology, business administration and water governance) are implemented in the figure. Then, when writing the theoretical framework, this figure was used as the backbone of the structure. Because of this causal connection between different variables, using parameters from different disciplines, was created.

The visualization of the integration in this case is therefore the integrated theoretical framework, with figure 1 serving as an overall visualisation of this process.

5. Selected method and data

For this research was both ecological and hydrological knowledge of the problem available. However, this is not yet available for this specific area. Most of this information focuses mostly on either other parts of the Mekong river, or it is too briefly or even too broadly discussed. Additionally, this information is not interlinked with the consequences for local communities and fishing businesses in the area. The water governance of this area is also not discussed combined with this disciplines in previous research. Therefore, this method will try to link the missing components to each other in order to conduct research in a more interdisciplinary integrated way.

This research was based on primary data. A large literature study has been done from different disciplines. In addition to using the various integration methods in the theoretical framework and the analysis, methods have been chosen for finding the final results based on the theories and concepts from the theoretical framework. In the literature study, the focus was mainly on the most likely negative environmental effects caused by the implementation of the possible dams. These adverse environmental effects were discussed in detail with regard to the possible impacts of the economic well-being of the local fisheries. This literature study on the negative environmental effects is further expanded in the

10 results. These results will form a basis to the overall societal-economical analysis, which deepens the economic well-being of the local fisheries. This analysis consists of an access analysis, five forces analysis and a SWOT analysis.

The access analysis, described by Ribot (2003), must be seen as a process to identify and map access mechanisms. Those mechanisms are used by certain institutions, groups or people to gain, maintain and control access. A deeper insight into these access mechanisms provides a better understanding of why institutions or people benefit from resources, even when they have no rights to those resources (Ribot, 2003). Identifying those access mechanisms that control the resource of fish in the Tonlé Sap region contributes to this research because it is important to notice how access is now divided in this region and how that access will change after the building of the possible dams. Researching this issue with this view on the concept of access will show how complicated, but also, how important fish catchment is for family-scale fisheries. This view integrated with earth sciences, knowledge about the fish populations and the five forces- and SWOT-analysis, it will give a better insight into the impact on the family-scale fisheries and its environment.

Performing an access analysis involves three steps (Ribot, 2003). First, the flow of benefits and interests has to be identified and mapped. Secondly, mechanisms of the actors to acquire gain, control, and maintain the resource and its distribution has to be identified. Thirdly, a power analysis has to be done. The third step is out of reach due to the time and resource limit of this paper. With this analysis, this research will delve deeper into the underlying processes and mechanisms of access applied to the issues in the Tonlé Sap region. There will be a focus on family-scale fisheries. In order to make a proper access analysis, the concepts of access and property rights will first be explained and applied in the next section. Furthermore, the research will be done at the various actors who influence the access for minority groups and how this has formed throughout history (Ribot, 2003). The recognized mechanisms will be distinguished in the analysis.

The business analysis that can be linked to the access analysis is the five forces analysis. Porter's 5 forces analysis can be used to expose industry strengths, threats and weaknesses (Volberda et. al., 2011) the strengths and weaknesses could be used to decide a fitting policy. As stated in the introduction a Porter's 5 forces analysis consist of 5 forces: (threat of new entrants, bargaining power of suppliers, bargaining power of consumers, substitute products and rivalry among competition.) which could be used for an industry broad analysis, in terms of competition and attractiveness of the industry. While a five forces analysis may be a useful tool to analyse the state of the current industry, it has its downsides: the first criticism is that the model is not dynamic enough. It only analyses the current situation and does not take time into account (Thurlby , 1998). Further is this model based on the industrial organization field of economics and does the model not asses the core capabilities and resources from inside the companies (in this case the local fishermen) (Rivard, Raymond & Verreault, 2006). A five force analysis could provide insights of the current industry. And thereby offering potential topics that require attention of policymakers. The information that is gathered in the five force analysis has been used to make a SWOT analysis. A SWOT analysis could be useful because it provides direct information on which area’s and factors it is required to base the policy(s) around to keep a sustainable environment. The disadvantages of a SWOT analysis are that it is originally meant to be used by a single company however it could be used for an entire industry. Another disadvantage is that in some cases the rules and boundaries of a SWOT analysis can be vague especially in the external factors (Gürel, 2017). Further does a SWOT analysis not guarantee to bring any improvements (Gürel, 2017), it could however expose the origin of the problems, which allows Policy makers to come up with solutions for these problems.

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6. Results

This chapter consists of the results to provide a clear and complete answer to the research question. These results are based on the integrative technique that is used. To provide a clear overview of the impacts of dams, alterations to figure 1 has been made and the implementation of dams has been added. This resulted in figure 2. The following paragraphs will provide the results according to this figure.

Figure 2. Most important concepts and theories relating to the fish stock within the Mekong river and Tonlé Sap river including positive (+) and negative (-) correlations and how dam implementations influence these topics.

On the lower Mekong river in Cambodia, three large dams are expected to have major ecological consequences once they are developed. The Lower Sesan 2, Stung Treng, and Sambor, each successively increasing in size, will be developed by 2030 (Baran, et al, 2015). These dams will change the flow regime of the river. Generally, the main impact of dams is the reduction of peak flows (Ligon et al., 1995). These modified water flows and flood patterns are the biggest negative effect of dams for the ecosystem. The reduced peak flow leads to the reduction of the large variations in water levels. As a result, the water level rise decreases and therefore also the water velocities (Zhong & Power, 1996). Baran et al. (2007) states that the flow into the Tonlé Sap lake will decrease by between 4,5 and 11 cubic kilometres. Moreover, the flooding in the Tonlé Sap lake will delay and the duration will reduce due to upstream developments on the Mekong river. The delay could be as much as one month, while the duration can vary between one and two weeks. Due to the delayed flooding, the arrival of oxygen-rich waters will also delay. In the dry season, the Tonlé Sap lake will have declined oxygen levels that depend on the flooding from the Mekong river to be refilled. Eggs and larvae are dependent on the floods for supply of oxygen, since they are not able to relocate (Baran et al., 2007). In addition, the height and the surface area of floods will decrease (Baran et al., 2007). Once the water flows and floods are lost, the costs of rehabilitating their ecological functions are very high (Baran et al., 2007).

The reduced water velocities will decrease the spawning grounds, since the velocities over the spawning grounds will not be fast enough (Zhong & Power, 1996). This has several negative consequences. First of all, the reduced water velocities cause spawning gravels to be lost. The majority of them will most likely not reach the Tonlé Sap lake for the formation of spawning grounds (Ligon et al., 1995). Secondly, the development of small channels is prevented due to the reduction in peak flows. Peak flows are needed for the transport of sediment, when these flows are reduced it leads to more

12 deposition of sediments. Small channels are filled in and the river will get less threaded. Due to the disappearance of braided reaches, the grounds where deposition of spawning gravels can take place, will be lost. Thus, the grounds where spawning can take place will reduce (Ligon et al., 1995). This will lead to a reduction of the fish reproduction (shown in figure 2).

A previous study by Wild and Loucks (2014) on dams in Cambodia shows that after dams were implemented about 40-80% of the sediments were trapped within the dams. A study conducted by Kummu and Varis (2007) shows findings on the trapping efficiency of different dams on the upper Mekong Delta. A trapping efficiency of 100% means that all sediments will be trapped in the reservoir. The Manwam dam, which has 1.6 times the capacity of the Stung Treng, but half the capacity compared to the Sambor dam, has a trapping efficiency of 75%. Therefore, a high TE can be expected for the Lower Sesan 2, Stung Treng, and Sambor as well. Due to the sedimentation accumulation within the reservoir on the Mekong river, sediment deprivation may occur. The rivers, where the Lower Sesan 2, Stung Treng, and Sambor are currently planned for construction, are among the most influential sources for sedimentation for the Mekong river stream (Baran et al, 2015). After implementation of these dams on the Mekong river a 47-84% reduction in nutrient loads is expected (Kummu et al., 2008).

Furthermore, the upcoming dams will also directly affect the migration, as illustrated in figure 2. The dams will act as a physical barrier to fish migration by blocking the upstream migration (Zhong & Power, 1996). As a result of the barrier fish eggs and larval stages will be compromised due to the trapped juvenile life stages in the impoundments. Especially the dams in the lower and middle reaches of the lower Mekong basin will affect the fish migration to the Tonlé Sap lake (Dugan et al., 2010). If the migration is halted due to the decreased water levels, the fish will not be triggered to migrate upstream and will stay put. The fish will therefore not reach their spawning grounds. The impacts on the fish migration of dams will matter significantly for the migratory species. As stated in the previous part of this paper, 48% of fish species are migratory (Kang et al., 2009), thus a change in migration routes has a large impact on the ecosystem of the Mekong basin. These species are highly dependent on these migrations for their spawning, feeding and habitats (Barlow et al., 2008).

Research done by Baran, Starr & Kura (2007) shows that sixteen of the migratory species are sensitive to hydrological migration triggers that will be implemented by dam construction. The building of these dams thus has serious environmental consequences, also illustrated in research conducted by Kang et al (2009). According to this paper, the closing of the dams will cause not only habitat fragmentation, but also alternations in the depth, dissolved oxygen, light availability and temperature of the Mekong river. Since migratory fish are reliant on these factors for their movement upstream to be able to spawn, changing these factors will alter their chances of survival. It is known that the implementation of a dam causes the water temperatures of the water below it to decrease. Particularly decreased water temperatures cause a change in the environmental conditions downstream that negatively affect the fish reproduction (Weber et al., 2013). The decrease in temperature could be as much as 6.5 Celsius degrees and it can cause delayed fish spawning and embryo development (Zhong & Power, 1996; Weber et al., 2013). Late hatching can have serious consequences for some fish species and, in combination with the lower temperatures of water, can reduce the fish growth. Warm water fishes in particular are affected by the lower temperatures and will most likely disappear (Zhong & Power, 1996). Likewise, the water temperature that will be released from dams will function as suppression to the factors that trigger the fish to migrate. Because of all these factors, the fish will develop new migration cycles. The research done by Kang et al (2009) states that while some fish species with a high breeding ability and a short reproduction cycle will be able to adapt to these changes, other fish species that do not have such qualities could possibly become extinct in the area (Kang et al., 2009). The paper published by Pool et al. (2017) supports these claims, stating that the interaction between the fish species and their habitat is highly specific, and changes in their niche cannot be implemented without the loss of certain species

13

and the decline of others (Pool et al., 2017).

In addition, the research done by Baran, Starr & Kura (2007) showed no positive long-term effects of dams on the fish populations in the Mekong basin. So combined the changed flow regime, nutrient deprivation, and as a result the decreased flooding and changing temperature will drastically influence fish stock in a negative way.

The fish stock is a factor that influences many other components. The fishing industry will change, given that the fish population will decline. The analysis made (Porter’s 5 forces) is explained in the points below. In table 1 the results are given.

1. For the threat of new entrants, the force is high, because the boundaries to enter this industry are low, with the low capital requirements to enter the industry (Fao, 2011), and low product differentiation (Drameh, 2000). The boundaries of entry are unlikely to change due to the fish scarcity.

2. The power of suppliers, in this case the supplier would be the sellers of the equipment for fishing. This force is low, since it the equipment is mainly made out of wood and rope (Fao, 2011), which are cheap in acisition, reusable and relatively easy to be crafted. This will most likely not change if fish will become scarcer.

3. The Bargaining power of consumers is on the one hand, people need nutrition and Cambodia’s main source of protein consumption comes from the fishing industry (Fao, 2001) this makes consumers more less powerful. On the other hand are the switching costs to find another source of nutrition is low, which strengthen the power of consumers since consumers could find another supplier, because of the scarcity the prices are likely to rise and the power of consumers will decrease.

4. The threat of substitute products are low, because customers in Cambodia do not yet have another sufficient source of protein since currently these industries are not big enough to provide Cambodia’s protein demand, the current industry for livestock is way smaller than the fishing industry (Fao 2011).

5. The rivalry among competitors is very high because the market is very fragmented (Teh, Et al., 2019) first are there are a lot of small companies battling over the same resources. And secondly those companies are battling to sell those resources on the market. the implementation of the dam and the subsequent loss of fish stocks will make the rivalry even bigger because the total amount of resources declines.

Overall from this five forces analysis above can be concluded that the fishing industry is already a competitive industry since there are a lot of companies competing over a finite resource and it will will likely become more competitive because of the scarcity.

Table 1: five forces analysis.

Market force This force _is…. This will change because

of the Dam

Threat of entrants High no

Bargaining power of suppliers Low no

Bargaining power of consumers Moderate yes, this will decrease.

14 Rivalry between competition High yes, this will increase.

With the information derived from the 5 forces analysis and additional literature, A SWOT analysis has been conducted which gave for the main strengths of the small-family-sized fisheries is that they are for the for a part self-sufficient ( Fao, 2011)Approximately 30-40% of the fish caught by family sized fisheries is used for home consumption (Teh, et al., 2019). This implies that there are not many other necessities for these fishermen to practise their profession i.e. they can live on with half of their current catch, this would also means that the fishermen are less vulnerable to tax raises because they do not sell all of their produced products. A weakness for these fishermen is that they are dependent on fish, if they catch no fish for a longer period, the fishermen do not have a source of income and food. Another weakness could be that one small-scale fisherman is only a fraction of the total system this means that if one stops to fish, the system would virtually stay the same. An opportunity for the small-scale fishermen is that Cambodia’s economy is developing (Hartmann, 2018), this typically increases the demand for animal products (FAO, 2006). A threat for the fishermen in the Tonlé Sap region could be the intense rivalry among competitors, especially regarding the predicted higher demand and lower fish population. Could this be a threat to the income of the small-scale fishermen, since there are dependent of that particular resource.

Table 2: SWOT analysis

Strengths self-sufficiency

Weakness dependency on fish

too small to change the current situation Opportunities

Growing demand for animal products

Threads

Rivalry among companies

From the five forces analysis combined with the SWOT analysis can it be concluded that the small-scale fisherman have a threatened industry environment and therefore is adequate policy required. It is important to take the self-sufficiency and growing demand for animal products into account within the policy-making. as well as the rights and access to the shrinking fish stocks. The access analysis specifically investigates the mechanisms of the family-scale fisheries. The access mechanisms that will be discussed are legal access, illegal access, access to technology, access to capital, access to knowledge, access to labor and access to authority, as described in (Ribot, 2003). In order to properly identify these mechanisms, it is important to first consider their history as well, because access mechanisms must be seen as a process that changes over time (Ribot, 2003). A better understanding of the evolution of those mechanisms will achieve a better comprehension of why certain mechanism are as they are. Cambodia has seen a lot of changes when it comes to water regulations (Dina & Sato, 2014; Teh, et al., 2019). A brief explanation of the history will therefore provide more insight into the current mechanisms.

15 From 1880 until 1970, the local fisheries had little or no control over the access to the fish stock and little attention was paid to negative impacts of the environment (Dina & Sato, 2014). This caused mechanisms for illegal fishing (Dina & Sato, 2014). A turning point was caused in 1970 by the civil war. Cambodia became a communist country and all privatization disappeared, even for small-family fisheries. In 1987, the old system of privatization returned, which privileged richer companies. Small-family fisheries had more difficulty accessing the resource of fish and this led them back to acts such as illegal fishing. In 2000, the government decided to partially abolish fishing lots and even in 2011 they were completely abolished. This resulted in gaining total access of the fish population by the local population. Yet, there is an increase in illegal fishing (Dina & Sato, 2014; Teh, et al., 2019). Interestingly, the government has in recent years undertaken regulations that have worked out favorably for the family-scale fisheries (Dina, T. & Sato, J., 2014; Teh, et al., 2019). This promotion has led to a broadening in legal access and access to labor for family-scale fisheries. Legal access increased because family-scale fisheries could easier obtain law-based property rights. The abolishment of fishing lots caused more job opportunities for the local populations. Further access mechanisms that can be recognized are access to technology, access to knowledge and access to authority. Access mechanisms for these three types of access are fairly limited for family scale fisheries. According to Teh et al. (2019), these restrictions and other regulations implemented by the government, to guarantee the safety of access for local families on the fish population, are nowadays still insufficient. The building of the possible new dams can make this worse. Currently, there is immense competition between large and small-scale fisheries due to scarcity. The scarcity is partly caused by seasonal floods, since there are dry and wet seasons, causing fluctuations in the amount of catchable fish (Teh et al., 2019). Besides this, illegal fishing is happening in this region as well, which makes the competition between the fisheries even stronger. Because all these fisheries set priority to their self-interest and not to the public interest, it can result in eliminating their common resource of fish (Hardin, 1968), resulting in the phenomenon of the tragedy of the commons (Teh et al., 2019).

When the planned dams are built, changes will be forced in these access mechanisms. In particular, a number of mechanisms that were legal will reduce for the family-scale fisheries. As a result, more illegal mechanisms will probably emerge. The main problem for the local population is that the fish populations will reduce. The family-scale fisheries may have a property right to be allowed to fish, but this does not mean they will have actual access (Ribot, 2003). This could lead to fisheries tending to fish in places that are protected by the government for environmental reasons, meaning that illegal access mechanisms might increase. Due to the increased scarcity and the high dependence on the fish population, every company will be inclined to seek only for their interest. What is meant by self-interest, is that companies are likely to fish more to catch as much as possible. When this process is continued, the shared resource can eventually be exhausted. This phenomenon is called tragedy of the

commons (Hardin, 1968).

Also, with a reduced fish population, there will probably also be a change in the mechanisms related to access to labor. Because there are fewer fish, fewer people can do the fisherman job. It is likely that more people will commit to rice farming (Hartmann, 2018). Especially because in this region, there are a limited number of people who are full-time fishermen (Béné & Friend, 2011). People who are unsuccessful in adjusting their mechanisms to provide themselves with money and food will lose capital. This will ensure a reduction in access to capital. With a smaller capital it will become more difficult to maintain control over the fish population, as maintenance will become difficult to pay.

16

7. Conclusion and discussion

From this research we can conclude that once a dam is implemented on the Mekong river this will influence the fish population, especially influencing fish migrations and reproduction. The building of the dams has serious environmental consequences. Firstly, dams can have large impacts on land-sedimentation fluxes. Sediment accumulation occurs within the dams and nutrient deprivation occurs in the Tonlé Sap. The closing of the dams will cause not only alterations of flow, sedimentation, less nutrient availability and habitat fragmentation, but will also cause alterations in dissolved oxygen, light availability and temperature of the Mekong river. Migratory fish depend on these factors. Changing these factors will alter their movement upstream for spawning, and with that change their chances of survival. The fish will likely develop new migration cycles. The fish species that will not be capable of this, will go extinct. Decreased flooding will also have a negative impact on the fish reproduction by reducing the fish migration to the spawning grounds. Thus, spawning grounds below the dams will be abandoned.Lastly, the altered temperatures lead to delayed hatching and negatively affect reproduction. These factors negatively affect fish growth, declining the fish stock. Due to the decline in fish stock, the fish become more scarce. Tragedy of the commons occurs. Furthermore, the government may also decide to protect several previous fishing areas. This as a result may cause even less access and further scarcity. These two combined may lead to less access to labor, less legal access due to the protection areas, and more illegal access because this is likely to increase when scarcity increases. These changes in access will directly affect the fishing industry. The pressure on the small family sized fisheries will increase. From the Porter’s 5 forces analysis it was concluded that the bargaining power of consumers will decrease, substitute products will increase and the rivalry between competition will increase. This means that the industry becomes more competitive. The SWOT analyses also stated that the highly fragmented market is battling in a smaller pool of resources while highly depended on fish stock. As a result, companies will be inclined to seek only for their self-interest, leading to tragedy of the commons.

To answer our research question: “How does an increase in dams on the Mekong river impact the ecosystem and local fisheries along the Tonlé Sap river?”, we can state that because of the above mentioned relationships between the several factors, an increase in dams on the Mekong river will negative effects for the Tonlé Sap river and floodplain and will have negative effects for as well fish

stock as fishing industry in the area.

While this research provided new insights into the situation, there are a couple of points that leave room for improvement. First of all, this research was conducted by researchers who have never been to Cambodia, and the research therefore only consists of a literature analysis. Furthermore, the research does not include all relevant disciplines, and lacks insights from philosophy, ethics or civil electrical engineering, to name a few. In order for the research to be complete, it should include the whole system in order to see the causal connections and relationships. Finally, the social economical part of the research focuses on the negative effects of the dam, and does not include the possible positive consequences of dams, such as new jobs that are created by building and maintaining the dams.

8. Recommendations

Specific data needs to be collected once the dams are implemented. This mostly includes data on the trapment efficiency of the specific dams since that will determine how efficient the dam is in terms of sedimentation interventions. This will lead to data on the amount of sediments that are accumulated before. Data needs to be collected for how much sediments are in the river now (Suspended Sediment Concentration) and how much nutrients they consists of and then that has to be collected as

17 well once the dam is implemented. This will show us how deprived the riverstream will be and to what extent the fish will be deprived of the nutrients. Also in depth research on the new migratory routes once the dams are constructed will give us insight on the causal relationship between dams and migratory routes (see figure 2). When these studies are conducted the causal relationships can be confirmed and expanded to which extent each problem occurs.

Furthermore, from the five forces- and SWOT analysis was concluded that an adequate policy is required when the news dams are implemented. In addition, the access analysis concludes that access towards the fish stock would be blocked causing access mechanisms to change towards more illegal mechanisms. Also because of this fish scarcity, tragedy of the commons could become a major part of this problem. One of the conclusions of the five forces- and SWOT analysis was that an adequate policy will be required because the fishing industry will be threatened. A good policy can improve this distribution of access (Gupta, 2013), even after the building of dams to reduce the scarcity problem. Therefore, we recommend possible solutions for the tragedy of the commons. A solution might be a non-governmental solution in which fishers mutually agree on the measures that could be taken. In theory this is a good solution because it rebuilds the sense that the fish are community goods, the problem is that this mostly works on smaller scales and that there is an opportunity for individuals who decide not to pay the prize and will utilize the benefits (free riders) (Ostrom et al.,1999). Another commonly used solution to the tragedy of the commons is regulation of the fish population, this means that the government would set a limit on how many fish an individual is allowed to catch, this works in other parts of the world (E.g. The European union currently has and it is quite successful (European commission for food farming and fishing, 2016). A disadvantage is that it is hard to regulate in developing regions since the market is so close to the fishermen themselves (Drammeh, 2000). Another possible solution would be the internalizing of externalities. Externalities are the cost to the communities of the fish that the fishing company nor the consumer pays for in the transaction, externalities is a form of market failure. This could be solved by taxation on the transaction of fish. Also could Privatisation be a solution, this would mean that fishermen get their part of the river to fish, an advantage is that it completely vanish the concept of common goods. This is however not a realistic solution since fish migrate, fish hatcheries are however worth considering (Hardin, 1968).

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