Sedimentation Damage to Marine Resources

Sedimentation Damage to Marine Resources

Primary Country: Philippines
Ecosystem: coral reef
Sample Value Estimates:
Comparison of gross revenues from diving and tourism in Bacuit Bay on the island of Palawan, given logging and no logging scenarios. Enhanced value of gross revenue PV over ten years with no logging, compared to with logging
  1. $17,572: using a 10% discount rate and
  2. $11,474: at 15%
Region: Asia
Data source: NOAA's Coral Reef Valuation Database

Publication information

Hodgson, G. Dixon, J A. “Sedimentation Damage to Marine Resources” Resources and Environment in Asia's Marine Sector, 1992

Addtional Notes

Assumptions: an annual decrease in coral cover of 1% for every additional 400 tons km2 of annual sediment deposition in Bacuit Bay and an annual decrease of one coral species (extinction) per increase of 100 tons/km2 annual sediment deposition. For each 1% annual decrease in coral cover, fish biomass is decreased by 2.43%

For each annual decrease of one coral species associated with coral cover loss, fish biomass decreases by .8%. (Required future annual logging area/area logged in 1986)*1986 sediment discharge =annual sediment discharge. This ratio remains constant until one year after the forest is fully logged, then sediment output decreases by 30% per year through the tenth year after logging began. Gross present revenue is discounted by both 10 and 15% to reflect the range used in the analysis of government and private projects. Book Chapter

Hodgson, Gregor and Dixon, John A.

1992

"Sedimentation Damage to Marine Resources: Environmental and Economic Analysis.""Resources and Environment in Asia's Marine SectorTaylor & Francis

New York

421-445

Logging/Fisheries/Tourism/Diving/Southeast Asia/Philippines

Logging in several Southeast Asian countries has had serious environmental consequences that have received much publicity. Mostly, however, this publicity has dealt with the land-based impact. This chapter deals with marine implications, in particular, the impact through situation on marine economic activities. The case study centers on a location in the Filipino island of Palawan. Marine activities include traditional fisheries and a new and sophisticated scuba-based tourism industry. It is found that logging on land severely limits the viability of these other two activities and restricts their income-earning. The results of a cost-benefit analysis show that logging produces a net negative cash flow. Hence, it is concluded that the viability of logging should be carefully reexamined. Revenue estimate: The no-logging option has a gross revenue present value of $17,572 (over ten years) more than the logging option using a 10% discount rate, and a $11,474 gross revenue PV more than the logging option using a 15% discount rate. Annual decrease in coral cover of 1% for every additional 400 tons km2 of annual sediment deposition in Bacuit Bay

Annual decrease of one coral species (extinction) in bacuit Bay per increase of 100 tons/km2 annual sediment deposition. For each 1% annual decrease in coral cover, fish biomass is decreased by 2.43%

For each annual decrease of one coral species associated with coral cover loss, fish biomass decreases by .8%. (Required future annual logging area/area logged in 1986)*1986 sediment discharge =annual sediment discharge. This ratio remains constant until one year after the forest is fully logged, then sediment output decreases by 30% per year through the tenth year after logging began. Gross present revenue is discounted by both 10 and 15% to reflect the range used in the analysis of government and private projects.

In this study, the net present value of gross revenues over a ten year period are estimated for three industries (fisheries, tourism and logging) under two scenarios: 1) continued logging in the Bacuit Bay drainage basin

and 2) a logging ban in the Bacuit Bay drainage basin.

Philippine island of Palawan.

Coral reefs, forests.

Logging, Tourism, Fishing

Sedimentation of reefs: Own calculations and observations

Tourism: advertised room rates, observed occupancy rates, planned expansion

Logging: Annual production and gross revenue from IBRD/World Bank study and another study, as well as projected logging concession

Fishing: Based on 1986 catch and gross revenue from commercial and non-commercial sources. Calculated with purse seine and with purse-seine excluded.

1986-1991

The no-logging option has a gross revenue present value of $17,572 (over ten years) more than the logging option using a 10% discount rate, and a $11,474 gross revenue PV more than the logging option using a 15% discount rate. Annual decrease in coral cover of 1% for every additional 400 tons km2 of annual sediment deposition in Bacuit Bay

Annual decrease of one coral species (extinction) in bacuit Bay per increase of 100 tons/km2 annual sediment deposition. For each 1% annual decrease in coral cover, fish biomass is decreased by 2.43%

For each annual decrease of one coral species associated with coral cover loss, fish biomass decreases by .8%. (Required future annual logging area/area logged in 1986)*1986 sediment discharge =annual sediment discharge. This ratio remains constant until one year after the forest is fully logged, then sediment output decreases by 30% per year through the tenth year after logging began. Gross present revenue is discounted by both 10 and 15% to reflect the range used in the analysis of government and private projects.N/AKim Barry

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