Survey of Krishnapatnam Mangrove Swamps

Invasion of Prosopis into mangrove wetlands

Ceriops decandra

Bruguiera cylindrica

Bruguiera gymnorhiza

My fourth field visit in the study of mangroves of Nellore district is Krishnapatnam where the Kandaleru creek merges with the Bay of Bengal. Here I have noticed two important mud flats, Burada Dibba & Chintala Dibba. At both of these places I found a fairly good mangrove diversity in view of influx of brackish water and fresh water daily.

• Mandal: Muthukuru
• Date of visit 24.02.2011
• Coordinates : 14⁰14¹.16-8.9¹¹-14⁰15^l01.25¹¹N, 80⁰07¹24.35¹¹-80⁰08¹¹01.99¹¹E

Two small islands which are actually broad mudflats, to the south of Krishnapatnam port were surveyed. The stations surveyed are surrounded by backwaters of Bay of Bengal and of Kandaleru creek.

Station 1 : Burada Dibba

This is actually a broad mudflat inundated by high tide everyday and so it is muddy. Mangroves are found at the fringe and interior also, and they are dense. Prosopis is not found, possibly due to daily inundation. Avicennia marina is the dominant species. Bruguiera gymnorrhiza and Ceriops decandra are also represented, but sparsely.

Ture mangroves :

1. Avicennia marina, 8-10 ft tall, with flowers and fruits

2. Ceriops decandra, 4-6 ft tall, with flowers and fruits

3. Bruguiera gymnorhiza (L.) Savigny, Rhizophoraceae, 6-8 ft tall, flowering

4. Excoecaria agallocha, 8-10 ft tall, no flowers

Mangroves associates:

1. Suaeda nudiflora, flowering

2. Clerodendrum inerme, flowering

3. Sesuvium portulacastrum, no flowers

Other flora:

Asparagus racemosus

Salinity: 35 ppt

Dissolved oxygen: 46

Water temperature: 29⁰C

Station 2: Chintala Dibba(Island)

Like Mud island, Chintala Dibba is also a broad mudflat, but a little raised so that it is not subject to daily inundation, except at the periphery. The interior of the mudflat is quite dry. Prosopis is of conspicuous occurrence.

True mangroves:

1. Avicennia marina, 8-10 ft tall, no flowers and fruits

2. Ceriops decandra, 4-8 ft tall, flowering

3. Bruguiera gymnorhiza, 6-9 ft tall, flowering

4. B.cylindrica (L) Bl, 5-6 ft tall, flowering

Mangrove associates:

1. Clerodendron inerme, flowering

2. Thespesia populneoides(Roxb) Koestel, Malvaceae, no flowers

3. Atriplex repens Roth Chenopodiaceae

Other flora:

1. Asystasia gangetica

Salinity : 35 ppt

Dissolved oxygen: 13.8

Water temperature : 28⁰C

Sediment samples were collected for chemical analysis.