Mangrove Ecology, Silviculture and Conservation

by Saenger, Peter

• ISBN13: 9781402006869
• ISBN10: 1402006861
• Format: Hardcover
• Copyright: 2003-03-01
• Publisher: Kluwer Academic Pub

Summary

Mangroves are a fascinating group of plants that occur on tropical and subtropical shorelines of all continents, where they are exposed to saltwater inundation, low oxygen levels around their roots, high light and temperature conditions, and periodic tropical storms. Despite these harsh conditions, mangroves may form luxuriant forests which are of significant economic and environmental value throughout the world - they provide coastal protection and underpin fisheries and forestry operations, as well as a range of other human activities. This book provides an up-to-date account of mangrove plants from around the world, together with silvicultural and restoration techniques, and the management requirements of these communities to ensure their sustainability and conservation.All aspects of mangroves and their conservation are critically re-examined. Those activities which threaten their ongoing survival are identified and suggestions are offered to minimise their effects on these significant plant communities.

Table of Contents

Preface	ix
Introduction: The Mangrove Environment	1	(10)
The Mangrove Flora	11	(38)
Introduction	11	(1)
The Mangrove Flora	11	(10)
Contemporary Biogeographical Processes	21	(4)
Floristic Attenuation with Latitude	21	(1)
Floristic Attenuation with Aridity	22	(1)
Floristic Changes induced by Natural Upheavals and Human Activities	23	(2)
Contemporary Biogeographic Patterns	25	(18)
Vicariants	26	(1)
Hybridizations	26	(1)
Discontinuities and Endemism	27	(1)
Atlantic and Eastern Pacific Biogeography	28	(4)
Indian Ocean and East African Biogeography	32	(5)
Australasian Biogeography	37	(2)
Western Pacific Biogeography	39	(2)
North-East Asian Biogeography	41	(2)
Towards a Global Biogeographic History	43	(6)
Adapting to the Mangrove Environment	49	(52)
Introduction	49	(1)
Dealing with High Salt Concentrations	49	(14)
Salt Exclusion	50	(3)
Salt Extrusion	53	(4)
Storage of Salt	57	(1)
Succulence	58	(2)
Compartmentalization	60	(2)
Osmocompensation	62	(1)
Conserving Desalinated Water	63	(12)
Xeromorphic Features	63	(5)
Transpiration	68	(5)
Optimizing Leaf Temperatures	73	(2)
Root Aeration in Waterlogged Soils	75	(9)
Morphological Adaptations	75	(6)
Physiological Adaptations	81	(2)
Metabolic Adaptations	83	(1)
Surviving Seawater Dispersal	84	(17)
Vivipary and Cryptovivipary	84	(3)
Propagule Production	87	(4)
Propagule Dispersal and Establishment	91	(10)
Physico-chemical Factors and Mangrove Performance	101	(46)
Introduction	101	(1)
Temperature	101	(4)
Mangroves and Low Temperatures	102	(1)
Responses to High Temperatures	103	(1)
Inter- and Intra-specific Differences	104	(1)
Light and Photosynthesis	105	(9)
Photosynthetic Efficiency of Mangroves	105	(5)
Canopy Gaps: Gap-enhancement of Reproduction and Growth	110	(3)
The Mangrove Understorey and the Role of Sulfides	113	(1)
Wind and other Atmospheric Phenomena	114	(8)
Ambient Winds	114	(2)
Extreme Winds and Mangrove Vegetation	116	(5)
Hail	121	(1)
Lightning	121	(1)
Sedimentary Conditions and Processes	122	(15)
Mangrove Soil Development	122	(6)
Aeration and Drainage Properties of Mangrove Soils	128	(3)
Nutrients in Mangrove Soils	131	(6)
Salinity of Soil Water	137	(10)
Biotic Interactions and Mangrove Performance	147	(36)
Plant-Plant Interactions	147	(13)
Parasitism	147	(3)
Antagonism (Ammensalism)	150	(2)
Mutualism	152	(2)
Competition	154	(6)
Plant-Animal Interactions	160	(23)
Flowering and Pollination	160	(6)
Bioturbation of Sediments	166	(2)
Grazing and Trampling (Leaf Herbivory)	168	(8)
Other Mutualistic Interactions	176	(3)
Trophic Pathways	179	(4)
Mangrove Structure and Classification	183	(24)
Classification of Mangrove Communities	183	(11)
Phytosociological Classification	183	(1)
Classification Using Structural Attributes	184	(3)
Classification Using Geomorphological Settings	187	(3)
Classification Using Physiographic and Structural Attributes	190	(4)
Zonation of Mangroves	194	(13)
Shoreline Zonation	194	(7)
Longitudinal Upriver Zonation	201	(3)
Similarities and Differences in Shoreline and Upriver Zonation	204	(3)
The Value of Mangroves	207	(22)
Introduction	207	(2)
Components	209	(10)
Plant Resources	209	(4)
Fisheries Resources	213	(2)
Wildlife Resources	215	(1)
Water Supply Resources	215	(1)
Agricultural Resources (including Salt Production and Aquaculture)	215	(1)
Forage Resources	215	(1)
Water Transport Resources	216	(1)
Recreational Resources	217	(1)
Energy Resources	217	(1)
Pharmaceutical Resources	218	(1)
Functions	219	(4)
Shoreline Protection	219	(1)
Windbreak and Storm Protection	219	(1)
Sediment Regulation	219	(1)
Nutrient Retention	220	(1)
Water Quality Maintenance	220	(1)
External Support	221	(1)
Groundwater Discharge and Recharge	222	(1)
Local Microclimatic Stabilization	223	(1)
Attributes	223	(2)
Biodiversity	223	(1)
Uniqueness and Heritage	224	(1)
An Economic Perspective	225	(4)
Mangrove Silviculture and Restoration	229	(42)
Introduction	229	(1)
Objectives for Mangrove Planting	229	(14)
Setting the Objectives	230	(1)
Timber Production	231	(6)
Shoreline Protection, Channel Stabilization and Storm Protection	237	(1)
Fisheries and Wildlife Enhancement	238	(1)
Legislative Compliance	239	(1)
Social Enrichment	240	(1)
Ecological Restoration	241	(2)
Macropropagation of Mangroves	243	(4)
Direct Planting of Propagules collected from the Wild	243	(1)
Outplanting of up to One Year old Nursery-raised Propagules	244	(1)
Outplanting of small Seedlings after Nursery-raising	244	(1)
Direct Transplanting of Seedlings and Shrubs	244	(1)
Raising of Air-layered Material	245	(1)
Use of Stem Cuttings	245	(1)
Use of Propagule Segments	246	(1)
Tissue Culture or Micropropagation of Mangroves	247	(2)
Site-Species Matching	249	(3)
Some General Principles	249	(1)
Nursery and Planting Techniques	250	(2)
Field Trials	252	(1)
Silvicultural Management of Planted Areas	252	(4)
Objectives for Management	252	(1)
Site Management	253	(1)
Natural and Assisted Regeneration	253	(2)
Cost of Assisted Regeneration	255	(1)
Plantation Performance	256	(13)
Optimal Planting Season	256	(1)
Optimal Initial Spacing	257	(1)
Survival	257	(1)
Standing Stock	257	(8)
Mean Annual Increment	265	(3)
Rotation and Thinning Schedules	268	(1)
Indices of 'Health' in Mangrove Communities	269	(2)
Conservation and Management of Mangroves	271	(32)
The Need for Mangrove Management	271	(4)
Management Frameworks	275	(2)
Some Specific Management Issues	277	(17)
Excessive Extractive Use	277	(1)
Discharge of Wastes	278	(4)
Hydrocarbon Contamination	282	(4)
Reclamation and Foreshore Development	286	(5)
Mangroves and Global Climate Change	291	(3)
Management Tools	294	(5)
The Reserves	294	(3)
Zoning of Mangrove Areas	297	(1)
Ecosystem Modelling	298	(1)
Raising Public Awareness	298	(1)
Future Prospects of Mangroves	299	(4)
References	303	(48)
Index	351