Some pot ent i al st ressors t o be avoi ded or eli mi nat ed are

Some pot ent i al st ressors t o be avoi ded or eli mi nat ed are

◆ Disturbing human ac tivities ( shrimps po nds, c lear- c uts, dykes, etc . ) ◆ Hypersaline o r ac id sulphate so ils ( usually after intensive shrimp farming ) ◆ Overg razing by animals ◆ Blo c ked tidal inundatio n ◆ Lac k o f g ro undwater ◆ Sho reline abrasio n and lo wered substrate level

5 6 Mang ro ve Resto ratio n

Thi s f our hect are shri mp pond exi st s i n t he area wi t h t he most ext ensi ve shri mp pond development on t he i sland. About half of t he ponds i n t hi s regi on are di sused, and half of t hose exi st wi t hi n t he 2 0 0 m coast al mangrove buf f er zone “requi red” by nat i onal law.

to determine ho w mang ro ve areas have c hanged and why.

S S St ep 4: Select an Appropriat e Res S S t ep 4: Select an Appropriat e Res t ep 4: Select an Appropriat e Res t ep 4: Select an Appropriat e Res t ep 4: Select an Appropriat e Rest orat ion Sit e t orat ion Sit e t orat ion Sit e t orat ion Sit e t orat ion Sit e

Often there are a number o f different sites available fo r po ssible resto ratio n, so it’s impo rtant to start by selec ting o ne that has a fairly g o o d c hanc e o f ac hieving yo ur resto ratio n o bjec tives. Fo r example it sho uld

be a site that c o ntained mang ro ves in the rec ent past o r presently c o ntains deg raded mang ro ves. Also like any pro jec t o ne undertakes yo u sho uld have the c apac ity and reso urc es, inc luding peo ple, equipment, time and financ es to see it tho ro ug h to c o mpletio n. Ownership o r user rig hts issues are c ritic al to have wo rked o ut at this stag e befo re any physic al wo rk beg ins. There may be an o ppo rtunity to bring the planned resto ratio n area under leg al c o mmunity o r c o - manag ement arrang ements whic h o ften c an take time but may

be impo rtant fo r lo ng term suc c ess.

Global Nat ure Fund – EU Asia Pro Ec o IIB 5 7

S S S S St ep 5: Hydrological Rehabilit at ion D esign t ep 5: H ydrological Rehabilit at ion D esign t ep 5: H ydrological Rehabilit at ion D esign t ep 5: H ydrological Rehabilit at ion D esign t ep 5: H ydrological Rehabilit at ion D esign

A basic theo ry behind hydro lo g ic al rehabilitatio n is the rec reatio n o f natural slo pe and substrate heig ht, whic h will suppo rt no rmal tidal flo w, and the natural re- establishment and g ro wth o f mang ro ve seedling s. Tidal streams run thro ug h mang ro ve areas fro m the terrestrial edg e to the sea. Their unhindered flo w is impo rtant, bec ause tidal streams are fed fro m the inland side by g ro und water, spring s, runo ff and streams and are c o nnec ted to the sea thus fac ilitating the exc hang e o f tidal waters in and o ut o f the mang ro ve area. When tidal streams are disturbed, a mang ro ve may dry o ut, and die o ver time.

Fo r the resto ratio n o ne o ptio n is to level dike walls o f disused shrimp po nds. If yo u c anno t level dike walls entirely, o pening strateg ic breac hes in the rig ht plac es may be eno ug h to suppo rt the exc hange o f tidal waters and sho uld lead to further deg radatio n o f the dike walls o ver time. The „ rig ht plac es“ are usually the mo uths o f histo ric tidal c reeks. A sec o nd o ptio n is to bac kfill an exc avated area, to c reate a targ et resto ratio n site with the same ge neral slo pe, and the exac t tidal elevatio ns relative to the benc hmark referenc e site, thus insuring that the hydro lo g y is c o rrec t.

If yo u are planning nurseries, it is indispensable to scrutinise the co nditio ns o f the po tential lo catio n. There is a reaso n why mangro ves are no t already there o r were no t there in the recent past o r have disappeared recently ( see step 3) . Once yo u find o ut why, see if yo u can co rrect the co nditio ns that currently prevent natural co lo nizatio n of the selected mangro ve resto ratio n site. If yo u canno t co rrect tho se co nditio ns, pick ano ther site.

Abandoned Shri mp Farm Rest orat i on – Do i t ri ght ! Connect Ponds wi t h t he sea wi t h a well desi gned t i dal channels

Shri mp Farms: Bulungan, I ndonesi a.

So urc e : IUCN