• Aucun résultat trouvé

13 years of changes in the extent and physiognomy of mangroves after shrimp farming abandonment, Bali, Indonesia

N/A
N/A
Protected

Academic year: 2021

Partager "13 years of changes in the extent and physiognomy of mangroves after shrimp farming abandonment, Bali, Indonesia"

Copied!
1
0
0

Texte intégral

(1)

13 YEARS OF CHANGES IN THE EXTENT AND PHYSIOGNOMY

OF MANGROVES AFTER SHRIMP FARMING ABANDONMENT,

BALI, INDONESIA

Rinny Rahmania, Christophe Proisy, Gaëlle Viennois, Ariani Andayani, Frida Sidik, Aulia Riza Farhan, Niken Financia Gusmawati,

Juliana Prosperi, Olivier Germain, Hugues Lemonnier, Berni Subki, Suhardjono, Nuryani Widagti, Philippe Gaspar

http://www.indeso.web.id

Contact Person : Rinny Rahmania

E-mail : [email protected] Website : http://amap.cirad.fr

This work is part of and funded by the INDESO project (2013-2017) led by Balitbang Kelautan dan Perikanan (Ministry of Marine Affairs and Fisheries, Indonesia).

OBJECTIVES

Analysing changes in surface extents and physiognomy of

planted and natural mangroves in an estuary submitted to

aquaculture, man-made mangrove plantations and natural

recovery processes

Satellite

Date

Satellite

Date

Ikonos-2

12-Oct-01 GeoEye-1 01-Oct-10 09-Mar-02 WorldView-2 30-Jun-11 27-Jun-03 23-Oct-12 QuickBird-2 22-Sep-07 01-May-13 19-Jul-08 26-Mar-14 09-Jul-09

PERANCAK ESTUARY (S8.3916°; E114.628

°)

RESULTS

The mean rates of expansion for plantation (0.8 ha/year) are lower than natural mangroves (0.9 ha/year). Age of plantation and forest growth can be monitored.

Fine scale maps of mangrove cover changes between 2001 (left) and 2014 (right). Natural mangroves growing inside shrimp ponds (red) are discriminated from vegetation growing outside shrimp ponds (green).

METHODS

Estuary area : ~ 7 km² Rivers and artificial

channels : ~15%

4.2 km² (or 69%) of the

estuary are covered by 1399 shrimp ponds

2014

List of images acquired:

Time-series VHRS images & Forest inventory Natural areas Natural mangroves (NM) Planted mangroves (PM) No vegetation (NV) Early stage (ES)

Closed canopy/ adult mangrove (CC)

Open canopy/ young mangrove (OC)

Fine scale map of planted & natural

mangrove Other estuarine units Shrimp ponds/ hydrologically constrained (SP)

Images extracted (500m x 300m) over typical areas in Perancak estuary

2001

2009

2014

SP

NV

PM

OC

PM

CC

PM

ES

PM

CC

NM

NM

NM

Conversion of mangrove forest to aquaculture Mangrove plantation programs

1980

1990

2000

Decadal changes in Perancak

The Perancak estuary

is greening

Expansion rates of planted are lower than natural mangroves

Very high resolution satellite images allow a careful monitoring of

mangrove changes in the perspective of Integrated Coastal Zone Management.

Planted mangroves can be discriminated from natural mangroves. Extension and forest growth can be monitored.

CONCLUSION

Visual segmentation of mangrove stages:

Panchromatic channels have the finest spatial resolution i.e. 0.5 m for Quickbird-2 and

WorldView-2, also 1 m for Ikonos-2 images whereas other channels are provided at 2 m and 4 m.

no mangrove

plantations

natural mangrove

natural mangrove (shrimps ponds)

2001

2014

N

coastline

Références

Documents relatifs

This paper examines the potential of a matchless time series of 20 very high spatial resolution (VHSR) optical satellite images acquired for mapping trends in the evolution

opportunity in Nunatsiavut. However, it did not prevent local northern shrimp allocation holders from using northern shrimp as a way to individually and collectively support

Diversed patterns of rice-shrimp integrated, rice-shrimp integrated combining with fish and crab are main farming systems in.. Cell is the smallest unit that equals to

• The household average accumulation of income of the rich household class in those subzones where physical conditions allowed shrimp farming reaches a high value, while that of

We propose here a detailed description of the occurrence of bacteria on antennae and antennules of four hydrothermal species (Rimicaris exoculata, Rimicaris chacei, Mirocaris

Table S2: Morphometrics of the different antennal and antennular setal types of one coastal (P. elegans) and four hydrothermal (M. markensis) shrimp species. Values are given

We use the case of the shrimp sector in the Mekong Delta in Vietnam to explore the constraints in the transition to sustainable intensification in shrimp farming, using an

For this we develop a model that shows how ‡uctuations in mangrove area can impact the production in the French Guiana shrimp …shery.. We …rst extend an open access bioeconomic model