Coastal Lagoons - Chapter 2 docx

Identification of the

Lagoon Ecosystems

Angheluta Vadineanu

CONTENTS

2.1 Introduction

2.2 Conceptual Framework of Sustainable Use and Development

2.3 Spatio-Temporal Organization of Lagoon Ecosystems

2.3.1 Lagoon Ecotone

2.3.2 HGMU Spatio-Temporal Organization

2.3.3 Biocoenose’s Spatio-Temporal Organization

2.3.4 General Homomorph Model for Lagoons

2.4 Scientific Achievements Relevant for Sustainable Management

of Lagoons and Land/Seascapes

2.5 Challenges for Ecosystem Modeling

References

2.1 INTRODUCTION

Lagoon ecosystems are ecotones, or transition units of landscapes and sea/waterscapes.

A key aspect of lagoons is highly sensitive areas known as wetlands, the interface areas

between the land and the water.

According to the definition accepted by the Ramsar Convention, wetlands exist

in a wide range of local ecosystems and landscapes or waterscapes distributed over

continents and at the land/sea interface. They are natural, seminatural, and human￾dominated ecological systems that altogether cover an average of 6% of the Earth’s

land surface.1

Wetlands are diverse in nature. They include or are part of areas such as beaches,

tidal flats, lagoons, mangroves, swamps, estuaries, floodplains, marshes, fens, and

bogs.1,2 The world’s wetlands consist of about three quarters inland wetlands and one

quarter coastal wetlands. Palustrine and estuarine wetlands, which include lagoons,

account for most of them.1

Exponential increase in human population and the corresponding demand

for food and energy resources as well as for space and transport have in the last

century stimulated the promotion of economic growth driven by the principles

of neoclassical economy. Current philosophy has promoted, and unfortunately

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still promotes today, the extensive substitution of natural and seminatural eco￾logical systems, or the self-maintained components of Natural Capital (NC),

into human-dominated components. Consequently, most of the natural and semi￾natural components, particularly wetlands, have been seen until recently as

“wastelands.” These areas are being extensively replaced by intensive crop farms,

tree plantations, commercial fish culture, harbors, and industrial complexes or

human settlements.2–6

The lack of scientific background for understanding and estimating the multi￾functional role of wetlands associated with the sectoral approach has resulted in lack

of appreciation by policy and decision makers of the resources and services that

these types of systems have produced.

However, these are some of the most productive units in the ecosphere. They

provide a wide range of self-maintained resources and services, from the viewpoint

of energy and raw materials. They replace such self-regulated systems totally or,

to a very great extent, they depend on the input of fossil auxiliary energy and

inorganic matter (e.g., chemical fertilizers) as well as on human control mechani￾zation (e.g., high-tech equipment for agriculture). Thus the ecological footprint

(EF) of many local and national socio-economic systems (SESs) themselves become

highly dependent on fossil fuels and underperform in providing services. The EF

basically tries to assess how much biologically productive area is needed to supply

resources and services, to absorb wastes, and to host the built-up infrastructure of

any particular SES.7

There has been an increase in scientific understanding and awareness among a

growing number of policy and decision makers, especially in recent years. They

now recognize that the structure and metabolism of any sustainable SES should be

well rooted in a diverse, self-maintained, and productive EF. This has launched a

new philosophy, derived from the theory of systems ecology and ecological eco￾nomics, dealing with “sustainable market and sustainable socio-economic develop￾ment.” This is an ecosystem approach, and new managerial patterns have emerged,

consisting of ecosystem rehabilitation or reconstruction for the improvement of the

EF and conservation through adaptive management of spatio-temporal relationships

among SES and the components of NC.

In recent years much work has been done to promote these new concepts.

Objectives and patterns now focus on reconstruction and management of natural or

seminatural ecological components (e.g., wetlands) as major initiatives in the EF of

many SESs. However, principally we are still in the process of conceptual clarifi￾cation, strategy, and policy development as well as designing and developing the

operational infrastructure or smaller scale of projects implementation.

This chapter presents a comprehensive analysis of the existing concepts, knowl￾edge, and practical achievements in the integrated or ecosystem approach for sus￾tainability or adaptive management of the relationships among SES and the compo￾nents of NC. It is an attempt to improve the conceptual framework and provide an

operational infrastructure for modeling and sustainable use and development of

lagoons, one of the components of the coastal landscape most sensitive and vulnerable

to human impact. This chapter thus provides the overall framework for developments

discussed in the following chapters of the book.

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2.2 CONCEPTUAL FRAMEWORK OF SUSTAINABLE

USE AND DEVELOPMENT

Since the Brundtland Report (1987 WCED) considerable effort has been directed

toward the development of a general definition of sustainability in order to implement

the vision of sustainability in practical policy decisions. There has been worldwide

recognition of the global “ecological crisis” faced by human civilization especially

after the UNCED Conference/Rio 1992. This has prompted those responsible for

formulating and implementing strategies and policies for economic development to

balance the spatio-temporal structure and metabolism of SES with the spatio-tem￾poral organization of the “environment” or with biophysical structures, the NC, and

their production and carrying capacity.

In this respect, this is an attempt to assess and integrate a wide range of

operational definitions that have been developed and checked in recent years.3–6,8–24

The following were identified as the basic requirements that must be met in order

to put into practice the concept of sustainability.

1. Assessment of the conceptual and methodological development of sustain￾ability that ensures establishment of state-of-the-art definition and identifi￾cation of main gaps and shortcomings and, therefore, the need for further

development and improvement.

2. Formulation of the basic elements of a dynamic model for co-development

of SES and NC or for sustainable use and development to serve as the

basis for promoting local, regional, and global transition.

3. Identification of the advantages and opportunities that each country and

region may have as well as the limits or constraints with which they may

be faced in the designing and implementing of long-term “co-develop￾ment” strategies and action plans.

4. Identification of existing shortages and gaps in the policy and decision￾making process dealing with sustainability and formulation of a compre￾hensive and dynamic model for the “decision support systems (DDSs).”

This will serve as the interface, or the operational infrastructure, and thus

enable us to balance the spatio-temporal relationships and the mass and

energy exchanges between the NC structure, serving as the footprint, and

the SES.

What follows is a brief description of the basic conceptual and methodological

elements to be relied upon in the co-development of SES⇔NC vision of sustainability

as well as the structure of the dynamic DSS that can put sustainability into practice.

The concepts and methods dealing with the “environment” have changed and

improved as ecological theory usually described as “biological ecology” has developed

from its early stage. The current ecological theory is more often and more appropriately

defined as “systems ecology” (Figure 2.1). The identification and description of the

natural, seminatural, human-dominated, and human-created environment has changed

as well. This change was from a former conceptual model that defined the environment

as an assemblage of factors—air, water, soil, biota, and human settlements—to the

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