Sustainable Mekong:

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Sustainable Mekong

• Tonle Sap Monograph Summary
• Mak Sithirith/Matthew Chadwick

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Overview of The Tonle Sap Lake

• a unique place
• the centre of Cambodia.
• the heart of the country,
• the centre of its ancient culture,
• the pre-eminent economic resource,
• a source of sustenance for the poor, and
• a most complex and fascinating ecosystem.

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Overview of Chapter

• Fish trade
• Fishing lot versus community fisheries
• Hydrological change and the fisheries impacts
• Sedimentation in the Tonle Sap Lake
• Agriculture Around the Lake
• Migration within the Tonle Sap Lake

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1. Fish Trade in the Tonle Sap

• Explores the issues around fish production and
  the fishing trade.
• Inland fisheries production 290,000-400,000 tons,
  with a 50-60 coming from Tonle Sap (ADB, 2004).
• A minimum of 50,000 tons and up to 100,000 tons
  are exported each year to ThailandThis is
  unreliable estimate due to under-reporting
  especially of the small traders.
• The Ministry of Economy and Finance (MEF)
  collects a 10 export tax on all fish exports.
• Fish for export must be sold to or through
  KAMFIMEX, a state owned enterprise managed by
  Ministry of Forest and Fisheries.

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• Findings Summary
• There remains a high level of uncertainty over
  the extent of the trade in fish due to limited
  knowledge of the size of the informal trading
  system.
• Relatively little post harvest processing and
  therefore value addition takes place in Cambodia.
• The fish trading system is tied intimately to the
  credit system. This has the benefit of providing
  a high level of stability to the system but
  limits the systems ability to act as a means of
  poverty alleviation especially for the fisher
  folk.
• The formal and informal taxation system accounts
  for a high portion of profits and is complex and
  extensive and again stifles the ability of the
  trade to meet its potential for reducing poverty.
  The system needs to be clarified, simplified and
  may more transparent.

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• Research Recommendations
• Many of the issues identified relate to fish
  trade from the Lao PDR also and there is a
  complex interchange taking place between
  Thailand, Lao PDR and Cambodia. The role and
  extent of the informal trading sector needs to be
  better understood
• The credit and taxation system (formal and
  informal) greatly reduces the profitability of
  the trade for those most at need. Potential
  modes for overhauling the system need to be
  investigated.

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2. Entitlement and Community fisheries in Tonle
Sap Lake

• Fishing lot in Cambodia has existed over hundred
  years.
• Some studies in the late 90s --The "fishing lot"
  remains a government's main instruments for
  fisheries managementthe fishing lot areas were
  enlarged .
• Fishing conflict between fishing lot and
  community.
• Fishing lot areas were reduced, estimated 56 and
  47 in the Tonle Sap Lake.

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• Key Findings
• The fishing areas cut for local people uses were
  the former areas used by local people.
• The research fishing lot was established in 1997
  
• In 2000, the Royal Government of Cambodia (RGC)
  announced to return all research fishing lots
  into the auctioned fishing lots.
• In 2002-2003, 37 fishing lots out of 38 were
  converted into the research fishing lots.
• The community management of the fishing lot was
  impossible. But the community management of
  areas cut from the fishing lot is now under the
  community fisheries schemes.

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• Research Recommendations
• Interrogate the disconnect between the
  historically and culturally rooted power
  structures and social relationships at the
  community level and the assumptions of top-down
  and expert led design of co-management programs
  and institutions in Tonle Sap.
• Review the factors which have contributed to the
  success or failure of co-management initiatives
  in other parts of the world, and compared this
  with the institutional framework and cultural
  context of Cambodia. Review meta-analysis of
  design principles for CPR co-management and
  attempt to apply them to the Cambodian context.

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3. Changing Hydrology and Fisheries Impacts

• In Tonle Sap Lake, in 1962-63water volume was
  68 million m3 (MRC, 1963),
• But in late 90s, the water volume was 50 million
  m3 (CNMC and Nedeco, 1998 FAO, ADB, DoF, 2003)
• This is suggesting a change in hydrology.

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• The higher the flood and the longer the flood
  duration the greater quantity of fish
• The freshwater fish production remained stable
  during the last ten years but catch composition
  in terms of size and species were critically
  changed (Tana and Todd, 2002).

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Key findings

• The lake functions as a natural floodwater
  reservoir for the Mekong and reducing salty water
  intrusion through release of water from the lake.
• The flood duration and flooded area of the
  floodplain are important for the fisheries
  productivity
• Fish and other aquatic species in Tonle Sap are
  affected by the water level variation, and
  sedimentation blockage. The feeding, spawning and
  nursery grounds would be disturbed and lead to
  declining biodiversity and productivity.

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Research gaps

• Study of the water balance calculations in Tonle
  Sap Lake to reflect the hydrological changes,
  such as the estimations of extreme situations
• The basic hydrological and limnological
  processes, such as sediment transport and
  dissolved oxygen levels, are now adequately
  documented, but the status and dynamics of
  biological productivity within the lake have not
  been well studied.
• Until the mid-1990s, catch statistics by the DoF
  were based on planned production rather than
  effective catches. Annual fish catch from the
  Tonle Sap ecosystem has in 2002 been reduced to
  235 000 tonnes, without explanation how this
  figure was obtained. Fish catch statistics should
  be improved to (a) reflect the biotic or abiotic
  state of the environment (b) reveal evidence
  for the impacts of hydrological change (c)
  indicate the diversity of other species, taxa or
  communities within an area.

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• An unrestricted flow of information between the
  countries of the lower and Upper Mekong Basin is
  urgently needed, to enable more quantitative
  estimations of possible development-related
  impacts on hydrology and fisheries.
• Zoning based on topography, flood characteristics
  and fisheries can increase remarkably the
  understanding of the interconnections between
  hydrological change, fish production and
  socio-economic issues.
• Policy advice on dam construction, irrigation
  schemes, and other development activities from
  insights into the hydrological changes for
  sustainable aquatic resources.
• More studies are required on the impact of
  climate change on hydrology of the Mekong River
  and Tonle Sap that will have significant effects
  on fisheries of the Tonle Sap.

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4. Sedimentation in Tonle Sap

• The current rate of sediment accumulation is low
  and not accelerated with respect to the long-term
  sediment dynamics of the system.
• However, there are many local problems associated
  with high sedimentation and erosion rates in the
  area and so calls for further investigations.
• .

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• No reliable calculations or source data on
  sediment bed-load exist. This may result in a
  tendency to underestimate the magnitude of
  sedimentation.
• However, a number of experts believe that the
  lake bottom is cohesive material, which basically
  happens no bed load but all the sediment
  transport is suspended load. This is subject to
  further investigation

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Findings Summary

• Current state of primary data on sediment in
  Mekong Basin and TLS does not provide for
  accurate quantification of the sediment load.
• Estimates of the rates of sedimentation of the
  TSL Lake vary wildly from an extreme of 40 mm/yr
  to lower than 0.2 mm/yr. Based on the scientific
  evidence, net sediment rate over the TLS Lake is
  low.
• Evidence points to the fact that sedimentation
  does not cover the lake evenly, but instead it is
  concentrated around the inflow points and as over
  bank sedimentation.
• Two locations on both ends of the TLS River are
  considered to be problematic from the
  morphological changes point of view, namely the
  Chhnoc Trou and at Chaktomuk areas.
• Dams upstream would sharply reduce the net inputs
  of sediment in TLS and consequently, the supply
  of sediment bound nutrients to its.
• Bed degradation is likely to occur in the Mekong
  River system due to increasing sand mining. If
  sand extraction is allowed to increase
  uncontrolled, it may be a very severe problem
  that will migrate in downstream direction and
  threaten the long term stability of the Lower
  Mekong and Bassac Rivers.

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Recommendation

• Development of methods for generating timely data
  and/or information on sedimentation trends and
  other related changes of environmental conditions
  of the Mekong River Basin.
• Examination, determining and redefining the
  causes and the problems related to the erosion
  and the disequilibrium of the morphological
  stability due to extensive sand mining.
• Determination of the nutrient inputs from Lake
  and surrounding sediments for fish production and
  model fish production which incorporates impacts
  of changed sediment inputs and Lake flooding.
• Development and visualisation of indices of
  historical channel migration, and classify
  factors influencing erosion and sedimentation at
  key local sites of TLS basin
• Quantitative assessment and understanding of the
  influence of built structures on fisheries by
  blocking migration and spawning areas, altering
  water quality and quantity, changing the temporal
  and spatial relationship and nature of the flood
  cycle, and degrading or fragmenting aquatic
  habitats of TLS.
• Assessment of importance of sediment (fish food
  chain, farm natural fertilizers)

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5. Agricultural Development and Intensification
in Tonle Sap - An Opportunity for Poverty
Alleviation?

• Low agricultural productivity due to low soil
  fertility, limited access to agricultural inputs,
  variability is rainfall that includes frequent
  droughts and floods, weak agricultural extension
  services that limit the transfer of improved
  production practices to farmers, poor
  infrastructure, limit access to markets, increase
  the cost associated with transport and limits
  access to credit and low commodity prices.
• Further agricultural development in surrounding
  watersheds threatens development in the basin as
  a whole.

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Research Recommendations Summary

• The groundwater potential of the Tonle Sap with a
  focus on assessing its potential role in small
  scale on farm irrigation.
• The potential of integrated farming systems as a
  means of enhancing livelihoods and food security
  in the Mekong Basin. This may include an analysis
  of the extent and adoption of integrated farming
  systems from a regional basis

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6. A Moving Target - Migration to and from Tonle
Sap and its Impact on Rural Livelihoods

• Will be presented in the next session

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Tonle Sap Database

• We have developed a Tonle Sap Database
  www.sumernet.org/tonlesap/eng
• Eg. FACT

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• THANK YOU