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Aquaculture and Fisheries Environment

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  • Indian Institute of Agricultural Biotechnoloy, Jharkhand

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The present book mainly deals with aquaculture and fisheries environment and updates the subject matter and problems to incorporate new concepts and issues related to aquaculture and fisheries environment. The extensive use of illustration is intended to increase the understanding and the concepts in context of the modern scenario. The book includes chapters contributed by outstanding experts and scientists from recognized institutions. This book would be of immense benefit to researchers, scientists, academician, students, entrepreneurs and fishers working in the field of aquaculture, limnology, freshwater ecology, aquatic ecosystem, environmental pollution and fisheries.
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AQUACULTURE AND FISHERIES ENVIRONMENT
The present book mainly deals with aquaculture and fisheries environment and updates the subject
matter and problems to incorporate new concepts and issues related to aquaculture and fisheries
environment. The extensive use of illustration is intended to increase the understanding and the
concepts in context of the modern scenario. The book includes chapters contributed by outstanding
experts and scientists from recognized institutions. This book would be of immense benefit to
researchers, scientists, academician, students, entrepreneurs and fishers working in the field of
aquaculture, limnology, freshwater ecology, aquatic ecosystem, environmental pollution and
fisheries.
CONTENTS
Biological Indicators of Aquatic Environment; Stress Responses in Fish; Types and Mode of
Action of Different Endocrine Disrupting Chemicals in Fish; Pearl Culture Technology in
Freshwater Environment; Management of Problematic Red Soil Based Upland Aquaculture
System in NE India; Ecological Requirements of Sustainable Fisheries in Lower Stretch of the
River Brahmaputra of North East India; Plankton Dynamics in Freshwater Fish Ponds in India;
Bioremediation; Management and Control of Land Degradation with Special Reference to
Aquaculture; Multiple Use of Water Through Integrated Fish Farming Systems; An Overview
of Fisheries
THE EDITORS
Dr. Sanjay Kumar Gupta M.F.Sc., Ph.D. has published 14 research and
review papers in both national and international peer reviewed journals. Dr.
Gupta has written many book chapters, scientific popular articles and success
story for popular magazines and has also published Hindi articles. He has
worked as reviewer for the various international scientific journals. Dr. Gupta
is editorial member of Environmental book series and editing books on various
environmental issues related to aquaculture and fisheries. He has presented
papers in diverse national and international symposia, workshops, seminars
and conferences. An appreciation letter from CIFE (Central Institute of
Fisheries Education), Mumbai has been presented to him for professional competency and
academic excellence in 2010. He has been awarded with “Young Scientist Award” for his outstanding
contribution in the field of Fish Physiology, 2013. Presently, he is working as ARS Scientist in the
Directorate of Cold Water Fisheries Research (DCFR), ICAR, Champawat Centre, Uttarakhand,
India.
Dr. Pawan Kumar ‘Bharti’ M.Sc., Ph.D., PGDISM, FASEA has written /edited
more than 32 books and about 55 articles in national /International journals,
proceeding and books. He has written many Hindi articles and scientific poems
in popular magazines. Dr. Bharti is the fellow and founder member of several
academic bodies. He is in advisory/editorial board of few scientific research
journals. He has been awarded
Haridwar Kavya Ratna
,
Vigyan Kavya Ratna
and few other awards in the field of scientific poetry & Literature. Dr. Bharti
was the member of 30th Indian scientific expedition to Antarctica. He has visited
to South Africa, Antarctica, UAE, Bhutan, and Nepal. Presently, he is working
as Scientist in Shriram Institute of Industrial Research, Delhi, India.
AQUACULTURE AND FISHERIES ENVIRONMENT
SANJAY KUMAR GUPTA
PAWAN KUMAR ‘BHARTI’
SANJAY KUMAR GUPTA
PAWAN KUMAR ‘BHARTI’
AQUACULTURE AND
FISHERIES ENVIRONMENT
AQUACULTURE AND FISHERIES ENVIRONMENT
DISCOVERY PUBLISHING HOUSE PVT. LTD.
NEW DELHI-110 002
D P H
Edited by
Dr. Sanjay Kumar Gupta
M.F.Sc., Ph.D., (ARS Scientist)
Directorate of Cold Water Fisheries (DCFR)
Experimental Fish Farm and Field Centre
(ICAR, Govt. of India)
Champawat (Uttarakhand), India
E-mail: sanfish111@gmail.com
&
Dr. Pawan Kumar ‘Bharti’
M.Sc., Ph.D., PGDISM, FASEA
Centre for Agro-Rural Technologies (CART-India)
20, Jamaalpur Maan, Raja Ka Tajpur
Bijnore (UP) - 246 735 (India)
Email: gurupawanbharti@rediffmail.com
AQUACULTURE
AND
FISHERIES ENVIRONMENT
Published by:
Tilak Wasan
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First Edition: 2014
ISBN: 978-93-5056-408-0
Aquaculture and Fisheries Environment
© 2014, Editors
All rights reserved. No part of this publication should be reproduced, stored in a
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photocopying, recording or otherwise, without the prior written permission of the
author and the publisher.
This book has been published in good faith that the material provided by authors is
original. Every effort is made to ensure accuracy of material, but the publisher and
printer will not be held responsible for any inadvertent error(s). In case of any dispute,
all legal matters are to be settled under Delhi jurisdiction only.
Printed at:
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Delhi
Aquaculture and fisheries have made significant contributions to the world
economy and to the health of the poor people as a major source of animal
protein especially in developing countries. Aquaculture is the fastest growing food
production sector with an average growth rate of about 8.8% accounting about
47% of the world’s fish supply (FAO 2012). Fisheries sector contribute over 1.0 %
of the National GDP and 5.3% of the agricultural GDP in India. The role of inland
aquaculture in particular is gaining increasing importance to enhance the overall
fish production of the country.
In aquaculture practices, fishes are subjected to a wide variety of environmental
and anthropogenic stressors. Environmental pollutants, disease, and various factors
involved are some of the examples of these stressors experienced by fishes in
captivity. Monitoring of adverse effects of pollutant is extremely important to regulate
and remediate toxicity. To test the toxicity, biomarkers/bioindicator is applied to
detect even low level of contaminants. Fishes serve as an excellent model for the
assessment of pollution and play significant roles in evaluating potential risk associated
with pollutants in aquatic environment. Additionally, fish, like other vertebrates, have
evolved strategies to counteract effects of stressors by eliciting coordinated set of
hormonal, physiological and consequent behavioral changes which are cumulatively
termed as the ‘stress response’. One of the important components of the stress
response at the cellular level is the induction of evolutionarily conserved heat shock
proteins (HSPs). Endocrine disrupting chemicals, a diverse group of synthetic
industrial and agricultural chemicals compounds can affect endocrine system of the
fish through mimicking the effects of endogenous hormones, antagonizing the effects
of endogenous hormones, altering the pattern of synthesis and metabolism of normal
hormones and modifying hormone receptor levels.
Pearl farming, one of the world’s largest aquaculture activities in terms of
value, practiced in the freshwater aquaculture environment. Indian pond mussel,
Lamellidens marginalis is the major species used in pearl aquaculture. Central
Preface
Institute of Freshwater Aquaculture (CIFA), Bhubaneswar has taken the lead
initiative to disseminate the technology of freshwater pearl culture to the fish farming
communities, entrepreneurs, researchers and students of the country. This book
provides the comprehensive coverage to briefly discuss about indigenously developed
technology of pearl farming in freshwater.
Pond bottom soil plays a pivotal role in determining pond productivity. India has
about 90% red-lateritic soils of its total area and majority of acid soils have pH
below 5.6. Management of this problematic red soil based upland aquaculture system
is of paramount importance. Present book briefly discusses the methodology
developed for ameliorating the acidic soil and water and the need of soil specific
fertilization especially for acidic soils to enhance aquaculture productivity.
The Brahmaputra River is the fourth largest river in the world in terms of
average flow discharge, flow through the Assam of North-east India furnishing
huge ichthyofaunal diversity to the region. Authors has made an attempt to assess
the ecological requirements (water quality features) of the lower stretch of the
Brahmaputra river for the survival and growth of fish fauna.
Success of Indian Major Carp farming exclusively relies on the primary food
production in the natural pond environment. Both phyto and zooplanktons is the
natural food items in freshwater fish ponds. Study on diversity of both phytoplankton
and zooplankton community are essential to learn plankton dynamics in ponds through
enrichment of autotrophic and heterotrophic pathways to enhance fish production.
To increase the production of shrimps (a highly price commodity in the Global trade),
bioremediation (bioaugmentation) technology is being employed which is gaining
considerable attention in recent years depending on the nature of the products used
and competition between species or strains of bacteria.
Land degradation described as an environmental phenomenon affecting dry
lands, a long-term decline in ecosystem function and productivity. Intensification of
sustainable aquaculture can be implemented to reduce the ecological effect without
affecting the productivity through management of deforestation, irrigation, urban
sprawl, mining and quarrying and land reclamation. Further, authors have briefly
described the importance of local and global policies and regulations imperative to
control the land degradation in order to increase the aquaculture production. With
population increase and economic growth, water demands for cities and for the
industry are growing much faster than those of agriculture. More focus should be
on sustainable management of water resources for optimal agricultural production.
This necessitates the exploration of opportunities for multiple use of water in
agriculture through farming system approach. Integrated farming system involving
multiple use of water could be an answer to resource scarce conditions in changing
climatic scenario.
The editors have tried hard to make comprehensive coverage of the fundamental
principles, current practices and trends in the field of aquaculture and fisheries
environment. This book updates the subject matter, illustrations and problems to
incorporate new concepts and issues related to aquaculture and fisheries environment.
Editors have made all possible efforts to avoid any omissions and errors but still
some may appear after publication. It is hoped that those oversights will not detract
the readers from the wealth information presented by the authors within this volume.
Publication of the document has been possible through enthusiastic support,
assistance and cooperation of dedicated scientists/workers from different institutions
working in the field and also in other areas of aquaculture and fisheries. The
processing and editing of various articles has taken long time, we express our sincere
gratitude to all the contributors for bearing with us.
We wish this book would be of immense benefit to researchers, scientists,
students, entrepreneurs and fishers working in the field of aquaculture, limnology,
freshwater ecology, aquatic ecosystem, environmental pollution and fisheries.
Sanjay Kumar Gupta
Pawan Kumar ‘Bharti’
Contents
Preface
1. Biological Indicators of Aquatic Environment 1
S.K. Gupta; Alkesh Das; Akriti Gupta and A.K. Prusty
2. Stress Responses in Fish: Potentials of Heat Shock Proteins for
Bio-monitoring and Disease Control 20
Rishikesh S. Dalvi and Asim K. Pal
3. Types and Mode of Action of Different Endocrine
Disrupting Chemicals in Fish 39
Prem Kumar and P. Priya
4. Pearl Culture Technology in Freshwater Environment 51
Shailesh Saurabh; U.L. Mohanty; J.Mohanty and P. Jayasankar
5.Management of Problematic Red Soil Based Upland
Aquaculture System in NE India 79
Mrinal Kanti Datta and Chandra Prakash
6.Ecological Requirements of Sustainable Fisheries in
Lower Stretch of the River Brahmaputra of North East India 10 2
Bhaskar J. Saud and Mitali Chetia
7. Plankton Dynamics in Freshwater Fish Ponds in India 12 5
Madhumita Das; Biswajit Dash and Loveson L. Edward
8. Bioremediation: A Novel Tool for Environment Friendly
Shrimp Aquaculture 140
Shubhadeep Ghosh; M.V. Hanumantha Rao; Ritesh Ranjan;
Biji Xavier; Loveson L. Edward; Muktha Menon;
Pralaya Ranjan Behera and N Rajendra Naik
9. Management and Control of Land Degradation with Special
Reference to Aquaculture 164
Sagar C. Mandal; Debtanu Barman; S.K. Gupta and S. Khogen Singh
10. Multiple Use of Water Through Integrated
Fish Farming Systems 18 7
A.K. Prusty; Poonam Kashyap; J.P. Singh;
S.K. Gupta and D.K. Meena
11. An Overview of Fisheries 196
Hussein Abdel-Hay Kauod
Index 207
A.K. Prusty, Scientist, Project Directorate for Farming System Research (PDFSR),
Meerut, Uttar Pradesh - 250 110, India.
Alkesh Das, Pursuing Masters Programme from Division of Aquaculture, Central
Institute of Fisheries Education, Versova, Mumbai - 400 061, India.
Asim K. Pal, Joint Director, Central Institute of Fisheries Education, Versova,
Mumbai - 400 061, India.
Bhaskar J. Saud, Research Scholar, Central Inland Fisheries Research Institute
(CIFRI), Regional Centre, HOUSEFED Complex, Dispur, Guwahati - 781 006.
Biji Xavier, Scientist, Visakhapatnam Regional Centre of Central Marine Fisheries
Research Institute, Visakhapatnam - 530 003, India.
Biswajit Dash, Scientist, Visakhapatnam Regional Centre of Central Marine
Fisheries Research Institute, Visakhapatnam, India.
Chandra Prakash, Sr. Scientist, Aquaculture Division, Central Institute of Fisheries
Education (Deemed University), Versova, Mumbai - 400 061, Maharastra, India.
Debtanu Barman, College of Fisheries, Central Agricultural University (Imphal),
Lembucherra, West Tripura - 799 210, India.
D.K. Meena, Scientist, Central Inland Fisheries Research Institute (CIFRI),
Barrackpore, Kolkata 700 120, India.
J. Mohanty, Principal Scientist, Central Institute of Freshwater Aquaculture
Kausalyaganga, Bhubaneswar - 751 002, Odisha, India.
J.P. Singh, Project Directorate for Farming System Research (PDFSR), Meerut,
Uttar Pradesh - 250 110, India.
Loveson L. Edward, Scientist, Visakhapatnam Regional Centre of Central Marine
Fisheries Research Institute, Visakhapatnam - 530 003, India.
M.V. Hanumantha Rao, Visakhapatnam Regional Centre of Central Marine
Fisheries Research Institute, Visakhapatnam - 530 003, India.
Madhumita Das, Scientist, Visakhapatnam Regional Centre of Central Marine
Fisheries Research Institute, Visakhapatnam, India.
List of Contributors
Mitali Chetia, Department of Zoology, Gauhati University, Guwahati - 781 014,
India.
Mrinal Kanti Datta, Assistant Professor, College of Fisheries, Central Agricultural
University, Lembucherra, Tripura (West), Pin - 799 210, India.
Muktha Menon, Scientist, Visakhapatnam Regional Centre of Central Marine
Fisheries Research Institute, Visakhapatnam - 530 003, India.
N Rajendra Naik, Visakhapatnam Regional Centre of Central Marine Fisheries
Research Institute, Visakhapatnam - 530 003, India.
Poonam Kashyap, Scientist, Project Directorate for Farming System Research
(PDFSR), Meerut, Uttar Pradesh - 250 110, India.
P. Jayasankar, Director of CIFA, Central Institute of Freshwater Aquaculture
Kausalyaganga, Bhubaneswar - 751 002, Odisha, India.
Pralaya Ranjan Behera, Scientist, Visakhapatnam Regional Centre of Central
Marine Fisheries Research Institute, Visakhapatnam - 530 003, India.
Prem Kumar, Scientist, aCentral Institute of Brackishwater Aquaculture (CIBA)
75- Santhome High Road, R.A. Puram, Chennai, India.
P. Priya, SRM, University, Potheri, Kattankulathur, Kancheepuram, Tamil Nadu
603203, India.
Rishikesh S. Dalvi, Assistant Professor, Department of Zoology, Maharshi
Dayanand College of Arts, Science and Commerce, Shri Mangaldas Verma
Chawk, Dr. S.S. Rao Road, Parel, Mumbai - 400 012, India.
Ritesh Ranjan, Scientist, Visakhapatnam Regional Centre of Central Marine
Fisheries Research Institute, Visakhapatnam - 530 003, India.
S.K. Gupta, Scientist, Directorate of Coldwater Fisheries Research, Chhirapani
Fish Farm, Champawat, Uttrakhand - 262 523, India.
S. Khogen Singh, Research Scholar, College of Fisheries, Central Agricultural
University (Imphal), Lembucherra, West Tripura - 799 210, India.
Sagar C. Mandal, Assistant Professor, College of Fisheries, Central Agricultural
University (Imphal), Lembucherra, West Tripura - 799 210, India.
Shailesh Saurabh, Scientist, Central Institute of Freshwater Aquaculture
Kausalyaganga, Bhubaneswar - 751 002, Odisha, India.
Shubhadeep Ghosh, Sr. Scientist, Visakhapatnam Regional Centre of Central
Marine Fisheries Research Institute, Visakhapatnam - 530 003, India.
U.L. Mohanty, Technical Officer (T-6), Central Institute of Freshwater Aquaculture
Kausalyaganga, Bhubaneswar - 751 002, Odisha, India.
Hussein Abdel-Hay Kauod, Veterinary Hygiene and Environmental Pollution
Department of Veterinary Hygiene and Management, Faculty of Veterinary
Medicine, Cairo University (Egypt).
Management and Control of Land Degradation
with Special Reference to Aquaculture
Sagar C. Mandal*; Debtanu Barman
S.K. Gupta and S. Khogen Singh
ABSTRACT
Land degradation can be described as an environmental phenomenon
affecting dry lands, a long-term decline in ecosystem function and
productivity. Asia has been highly affected and followed by Africa, where
as the Europe is the least effected. About 2.6 billion people are affected
by land degradation and desertification in more than 100 countries,
influencing over 33% of the earth’s land surface. The natural causes of
land degradation are earth quakes, tsunamis, droughts, avalanche,
landslides, mud flow, volcanic eruptions, flood, tornado and wild fire.
Man-made land degradations are due to land clearance, deforestation
overgrazing by live stock, in appropriate irrigation and over drafting,
urban sprawl and commercial development and pollution from industries,
quarrying, and mining activities. Implications and effects of land
degradations reduce productivity of land, migration of the people, damage
to basic resources and ecosystems, food insecurity and loss of biodiversity
with special reference to fisheries and aquaculture. The land degradations
can be controlled by management of deforestation, managing irrigation,
managing urban sprawl, managing mining and quarrying, managing
agricultural intensification and land reclamation. Intensification of
sustainable agriculture-aquaculture can be implemented to reduce the
ecological effect without affecting the productivity. Thus it is necessary to
have local and global policies and regulations to control the land
degradation.
99
99
9
Management and Control of Land Degradation with Special Reference to … 165
Keywords: Land degradation, biodiversity, reclamation, control, aquaculture.
INTRODUCTION
Land degradation can be described as an environmental phenomenon affecting
dry lands, leads to loss of economic and biological quality of an agricultural land
(Mantel & van Engelen, 1997). The Food and Agricultural Organisation (FAO)
defines land degradation as a long-term decline in ecosystem function (UNEP, 2007)
and productivity (Bai & Dent, 2006). It is the effect on biophysical environment by
disturbing the land either by human or by natural forces. Severity of land degradation
is about 30% of forestry, 20% of agricultural and 10% of grass land is undergoing
degradation (Bai et al. 2008). Soil degradation involves a number of physical,
chemical and biological processes. Soil erosion by water due to storms and soils
with poor surface structural stability is the most obvious form of land degradation.
The other forms of degradation seen in our state are salinisation, alkalisation,
laterisation and inundation.
It is estimated that land degradation affects about 70% of the world’s
rangelands, 40% of rain fed agricultural lands and 30% of irrigated lands. Salinity
affects about 30% of currently irrigated lands. Over ¼ of the world’s land area is
affected by desertification which is a potential threat to half of the world’s poor
people that live in dry land regions with fragile soils and unreliable rain, especially in
Africa. Declining soil fertility has a severe impact globally and, in Africa, average
yield losses are estimated at 8%, with up to 50% loss of productivity in certain
areas. Land degradation affects water resources, reducing water availability and
quality and altering the regimes of rivers and streams. Potential impacts include
flooding, silting of reservoirs and estuaries, groundwater depletion, salt water intrusion
into aquifers, pollution of water and salinization. Unsustainable rates of freshwater
use and contamination of water and soils by urban and industrial wastes are increasing
problems with environment, food safety and health implications.
Land degradation has major impacts on biodiversity through reducing land
quality and its capacity to support animal, plant and microbial life and through impacts
on natural ecosystems, especially fragile wetlands and extensive grazing systems in
dry land areas. Many inland water ecosystems and their fishery resources and
biodiversity on which large populations rely, are seriously threatened by urban and
industrial growth, deforestation, agro-chemicals and sediments from runoff. Some
26% of the world’s wetlands have already been lost, due largely to conversion to
agriculture or diversion of water for agriculture and aquaculture. Increasing land
degradation, desertification and deforestation are caused by poverty, population
pressure, unsuitable land use and unsustainable agriculture, grazing and forestry
practices, insecure land tenure, lack or misuse of technology, inefficient markets
and other institutional, policy and legal factors.
166 Aquaculture and Fisheries Environment
Poverty is both a consequence of land degradation and one of the causes.
Poor people deplete their resources through lack of capacity and opportunities to
meet their daily needs. Efforts to increase production and improve food security
and wellbeing, through intensification and new technologies have, in some cases,
resulted in negative environmental and health impacts. It has been shown that
economic long-term viability of technologies must be guaranteed for land users
including small holders as they will only envisage involvement and investments in
sustainable land use systems and better land husbandry practices if the resulting
benefits will be fully appreciated and internalised. Thus land use options must be
viable and socio-economic benefits must be emphasized in the promotion of good
practice (income, equity, livelihood, community cohesion, environmental). In addition,
to promoting good practices, satisfactory trade-offs need to be identified between
the objectives of farmers and other local resource users and those of the nation.
Externalities such as degradation, resource depletion, pollution and health impacts
need to be identified and, as appropriate, addressed through supportive trade, financial
and fiscal policies in order to encourage local management activities that also
contribute to national goals, such as watershed and water resources management
and biodiversity conservation.
There are two fundamental objectives of aquaculture development viz. it be
environmentally sustainable and that it be economically viable. These issues are
closely tied. It has been proved in numerous other human activities that if
development is not sustainable then it is not viable. For any proposed aquaculture
development, proponents must pay attention to planning principles, assess potential
effects, and establish processes to minimize these effects through good aquaculture
practices.
ISSUES AND FUTURE CHALLENGES
The ever increasing population growth and increased demands of urban and
rural populations are influencing land use, the status of land and water resources
and their potential to sustain the livelihoods and well-being of present and future
generations. Global trends and key factors of land use change in terrestrial
ecosystems include deforestation and fragmentation of forests, intensification of
agriculture and its expansion into marginal areas and fragile ecosystems, as well as
urban expansion and infrastructure development. Land degradation seriously affects
land resources in many tropical, subtropical and dry land regions of the world, with
severe impacts on much of the world’s population whose livelihoods depend on
agriculture, fisheries and land as well as on urban and rural food security. The
magnitude of these trends is inducing changes in global systems and cycles that
underpin the functioning of ecosystems and represent major environmental threats.
Such changes include global warming from the build-up of greenhouse gases and
its potential impacts; emissions that cause acid rain and threaten watersheds, as
Management and Control of Land Degradation with Special Reference to … 167
well as disruption of the global nitrogen and carbon cycles through burning of fossil
fuels, logging and land degradation and extensive use of chemicals and fertilizers.
HOW LAND DEGRADATION IS AFFECTED GLOBALLY
According to the estimates of global extend of land degradation shows that
Asia has highly affected and followed by Africa, where as the Europe is the least
effected (Zika & Erb, 2009). United Nations Development Programme (UNDP)
estimates $42 billion in income and 6 million hectares of productive land are lost
every year. As per UNDP the conditions in Africa are worsening with dust storms,
damaged water sheds, lost of forests and lower agriculture productivity, which is
linked to human poverty, migration and instability (WMO, 2005). In Botswana also
under threat because of soil erosion and unsustainable use of renewable natural
resources, where the most of population are depends on agriculture. Pakistan also
facing the threat of land degradation, by decreasing soil fertility and floods. In the
case of Sudan the population is depends on the livestock for their subsistence. It is
estimated that 2.6 billion people are affected by land degradation and desertification
in more than a hundred countries, influencing over 33% of the earth´s land surface
(Adams & Eswaran, 2000). The detailed degraded lands in dry areas as per the
continents have been given in Table 9.1.
Table 9.1: Estimates of All Degraded Lands (in million km2) in Dry Areas
(Dregne & Chou, 1994)
Continent Total Area Degraded Area % Degraded
Africa 14.33 10.46 73
Asia 18.81 13.42 71
Australia and the Pacific 7.01 3.76 54
Europe 1.46 0.94 65
North America 5.78 4.29 74
South America 4.21 3.06 70
Total 51.60 35.92 70
EFFECTS OF LAND DEGRADATION
The effect of land degradation is such that in the Philippines, it is estimated
that soil erosion carries away a volume of soil equivalent to one meter deep over
2,00,000 ha every year. In India, about 144 million ha of land are affected by either
wind or water erosion. Similarly, in Pakistan, 8.1 million ha of land have been lost to
wind erosion and 7.4 million ha to water erosion. The deforestation is also very
common. During 1980s, it is estimated that 4.0 million ha of forest were lost each
year in Asia and the Pacific. The destruction of the forests is mainly a result of
clearance for agriculture. The search for fuel wood, as well as the growing frequency
and severity of forest and bush fires, are also taking their toll. In Nepal, excessive
168 Aquaculture and Fisheries Environment
fuel wood harvesting and cutting for fodder have severely degraded forests-
approximately 40 per cent of buffalo feed and 25 per cent of the cow feed is
traditionally provided by the leaves of trees.
In India, which supports 15 per cent of the world’s cattle and 46 per cent of
the world’s buffalo, upland forests have been severely overgrazed. Deforestation
has led to a severe shortage of fuel wood and building materials in many areas.
Crop residues and animal manure, which were previously returned to the soil to add
valuable nutrients, are having to he burnt for fuel. The region’s grasslands are also
being destroyed-a matter of great economic importance since grazing is the largest
land use in Asia. Grasslands are under attack from over-intensive grazing and from
the incursion of marginal agriculture which often fails and then leaves a residue of
degraded land. It can also be said that as grazing areas decrease, livestock numbers
often increase. The grazing areas are often located at the source of important
catchment areas, influencing downstream agricultural and settlement so the cost of
their deterioration is high. The problem of the ‘vanishing grasslands’ is particularly
serious in countries where grazing lands are used communally, but livestock are
private property. It is virtually impossible to stop overgrazing in areas where grazing
rights are not defined. No nation in the region has an effective plan of action to
meet this challenge.
Land degradation is also altering hydrological conditions, where vegetative
cover is removed, the soil surface is exposed to the impact of raindrops which
causes a sealing of the soil surface. Less rain then infiltrates the soil. Runoff
increases, stream flows fluctuate more than before, flooding becomes more frequent
and extensive, and streams and springs become ephemeral. These conditions
encourage erosion; as a result, sediment loads in rivers are increasing, dams are
filling with silt, hydro-electric schemes are being damaged, navigable waterways
are being blocked and water quality is deteriorating.
Land degradation and changed river ecology caused by inland farming are
also challenges which need to be addressed to ensure production has a minimal
effect on natural biodiversity and ecosystems. Commercial aquaculture posses a
particular set of problems, with large-scale production and limited management in
some instances leading to critical environmental dames and irreversible ecosystem
degradation.
The Impacts of external environment on aquaculture may be positive or
negative. Nutrient enrichment of water bodies may provide nutrients beneficial to
aquaculture production in some extensive culture systems such as seaweeds and
molluscs. However, excessive loadings with urban and industrial wastes can have
severe consequences for aquaculture operations, particularly shellfish culture, when
exposed to contamination with toxic pollutants, pathogens and phycotoxins. With
the increasing aquatic pollution and physical degradation of aquatic habitats by
Management and Control of Land Degradation with Special Reference to … 169
other developments, aquaculturists can face risks of mass mortalities of farmed
stock, disease outbreaks, product contamination and reduced availability of wild
seed or broodstock.
TRENDS IN LAND DEGRADATION
Major trends related to land degradation and agricultural productivity globally
include:
Loss of water for agriculture and reallocation to cities and industries.
Reduction in land quality in many different ways, leading to reduced
food supplies, lower agricultural incomes, increased costs to farmers
and consumers, and a deterioration of water catchment functions.
Reduction in water quality due to pollution, water-borne diseases and
disease vectors.
Loss of farmland through conversion to non-agricultural purposes.
On average globally, only half of the nutrients that crops take from the soil are
replaced, and the removal of the other half slowly depletes the soils, often to levels
where productivity becomes impaired. Nutrients contained in harvested products
and in food flow from farmland to settlements, and from rural areas to cities. Most
of the nutrients in food consumed in cities are neither recycled nor otherwise re-
used, but either accumulate unproductively or pollute rivers and seas. Urbanization,
international trade and negligence of the environmental cost of soil nutrient removal
reinforce this process.
LAND DEGRADATION AND WATER PRODUCTIVITY
The potential gain in water productivity through land management interventions,
particularly to improve soil quality, is large and underappreciated. It is estimated
that water productivity in irrigated systems can be improved by between 20 and
40%, primarily through land management approaches. In rain-fed systems in
developing countries, where average crop production is very low and many soils
suffer from nutrient depletion, erosion and other degradation problems, potential
improvement in water productivity is even higher and may be as high as 100% in
many systems. When these gains are achieved by reducing unproductive losses of
water (primarily evaporation) or increasing transpiration efficiency, they represent
water productivity gains at even larger scales than the farm. This potential for
improvement is higher than that which can be expected through the genetic
improvement of crops or water management alone in the near future. The mitigation
of land degradation is therefore central to increasing water productivity and thereby
preserving both terrestrial and aquatic ecosystems and their accompanying services.
STATUS OF LAND DEGRADATION IN ARID REGION IN INDIA
The land degradation under different land uses in the arid region mainly the
desert of western Rajasthan and Gujarat, covering 28.5 million ha area, was mapped
170 Aquaculture and Fisheries Environment
using remote-sensing technique. It revealed that about 76% area of western Rajasthan
was affected by wind erosion, encompassing all the major land uses but mostly
croplands and dunes/sandy areas, while water erosion affected about 2% area
(mostly in croplands and scrublands), salinization about 2% (mostly in croplands)
and vegetation degradation nearly 3% (especially in scrublands and forests). Mining
activities have spoiled so far only 0.10% area, and degraded rocky areas covered
1% area. About 18% area was severely degraded and 66% slightly to moderately,
while 16% area was not affected by degradation. The mapping showed that about
1.3 million ha area of croplands in western Rajasthan was under severe wind erosion
(mostly un-irrigated). In arid Gujarat, water erosion was the most dominant process,
affecting about 43% of the total area (mostly in croplands), followed by salinity
(38%), while vegetation degradation (10%) and wind erosion (5%) covered smaller
areas. About 44% area was severely affected, 53% slightly to moderately and 3%
not affected. Large area under severe degradation was due to the huge area of the
Great Rann of Kutch and the Little Rann that have high natural salinity.
Increasing salinisation of land and waterways in agricultural areas due to
irrigation and deforest-ation is a global problem. Any aquaculture development using
saline water must not increase salinisation and must minimize the release of nutrients
to waterways. Consequently, the disposal of saline water from aquaculture systems
needs to be carefully considered.
CAUSES OF LAND DEGRADATION
The causes of the degradation can be either natural or human. The natural
causes includes earth quakes, tsunamis, droughts, avalanche, landslides and mud
flow, volcanic eruptions, flood, tornado and wild fire (Reynolds, 2001). As the natural
causes are uncontrollable, the human induced degradation is very important in view
of sustainability. Climate change, as result of human intervention over ecology is
another reason for the degradation (Barrow, 1991). Land clearance and deforestation
is the one of the major reason for land degradation (Reynolds et al., 2007). Many
other operations like overgrazing by live stock, in appropriate irrigation and over
drafting, urban sprawl and commercial development, land pollution including industrial
development, vehicle-off loading, quarrying can also leads to land degradation. The
vulnerability of the land like low level area, cost line area is more susceptible for
degradation (Salvati & Zitti, 2009). Land degradation can leads to many issues like
soil erosion, soil acidification, soil alkalinisation, soil salination, soil water logging and
destruction of the structure of soil which will directly effects the fish production in
the culture tanks because good aquaculture practices depends on good soil and
water quality parameters. It has direct impact on the agriculture and environmental
sustainability like reduced productivity, damage to basic resource and ecosystem,
food insecurity, loss of biodiversity, climate change and land slide mitigation, and it
can leads to a tremendous economic loss (Wasson, 1987). Desertification also leads
Management and Control of Land Degradation with Special Reference to … 171
to migration which will be threat to political economic instability (Zika & Erb, 2009).
Land reclamation is the process of recovering the land that has lost its productivity
and also make it use again or creation of new land from sea or river for the need of
human activities.
NATURAL CAUSES OF LAND DEGRADATION
The land degradation can be either by natural or by human influenced activities.
The natural causes include earthquakes, tsunamis, droughts, avalanche, landslides
and mud flows, volcanic eruption, flood, tornado, etc. Research shows that direct
impact of the earthquake on the land degradation and affected the agriculture in
ancient period (Leroy et al., 2010) which leads to drastic changes in agriculture for
a few years. The earthquake in 2004 in the region of Sumatra of Indonesia has
caused degradation of agricultural land. The earthquake in Sichuan, China in 2008
has destroyed 0.4 million hectares of high yield rice cultivating land and the texture
shows sandy to silty clay loam (Gang, 2008; Hulugalle et al., 2009). Drought is
another reason, but quantification of its impact is most difficult factors compared to
other natural disasters like tsunami or hurricanes. The effect of drought can vary
from region to region even though; they are identical in intensity, duration, because
of change in social characteristics. Soil can loss its structure aggregation because
of drying out of top soil. This dried up top soil can easily be blown away as a result
of wind and rain. So it effects the vegetation and agricultural productivity (Singh et
al., 2007; Zhao et al., 2008).
HUMAN INDUCED CAUSES
Many human activities are leads to land degradation directly or indirectly,
include deforestation, overgrazing by live stock, irrigation practices, urban sprawl
and commercial development (Chomitz et al., 2007) pollution from industries,
quarrying, and mining activities. The indirect activities included pressure on
agricultural intensification and population growth. Increase in the population increases
the need of food. About 220 million hectares of tropical forest have been degraded
1975 and 1990 mainly for food production (UNDP, 2004).
CLIMATE CHANGE
Changes is earth’s atmosphere have large influence on land. Since the industrial
revolution it is estimated that the global carbon emission to the atmosphere is about
136±55 GT (Gigatonne = 1 billion tone) (Anon. 2000) due to land use change and
soil cultivation, with depletion of organic soil pool is about 78±12 GT (Lal, 2004).
The terrestrial vegetation depends on temperature and precipitation. With decrease
in rain fall, vegetation becomes thinner. High temperature and low precipitation
leads to low organic matter production in soil and rapid oxidation. This leads to low
aggregation and is vulnerable for erosion by wind and water. In Africa, 25% and
22% of land is prone to water and wind erosion, respectively (Reich et al., 2001).
172 Aquaculture and Fisheries Environment
The climate stress is accounting for 62.5% of the all the land stress there. Rain fall
is the important factor that leads to land degradation. Less and over rain fall affect
the land either by desertification or excess, this will lead to soil erosion. Other
factors like flood and drought brought by climate also leads to land degradation. At
most of the dry land climate, there will be minimum clouds, which will increase the
intensity of the solar radiation, which eventually leads to land heating and rise in the
air temperature (WMO, 2005).
DEFORESTATION
In deforestation process, certain trees are cut down and or burned for human
use like timber, wood fire, industrialization and urbanization. Over population, force
deforestation by demanding land for shelter and agriculture. Demand of agricultural
is the one of main reason for deforestation (Kaimowitz & Angelsen, 1988). As per
FAO, each year 13 million hectares, about 0.18% (FAO, 2005a) of world forest are
lost by deforestation. An overview of deforestation figures around the globe has
been given in Table 9.2, which shows that how serious is the deforestation. It can
also reduce the content of water in soil, because fast evaporation of the soil water
and dried atmosphere and less rain which will make our river system dry up and it
will affect our natural fish biodiversity and germplasm as well. Therefore,
deforestation will lead to soil erosion. The top layer of soil can easily be washed out
and makes the soil unfertile and un-productive as well.
Table 9.2: An Overview of Deforestation Figures Around the Globe (FAO,
2005b)
Global Region Period Net Loss Hectare/Year
South America 2000-2005 4.3 million
Africa 2000-2005 4.0 million
Oceania 2000-2005 356000
North & Central America 2000-2005 333000
Asia 1990s 800000
Europe 1990s Expanding
OVERGRAZING
Over grazing is abuse of grassland, due to decrease in grassland and increase
in livestock numbers. The plant density will be reduced by overgrazing. It will not
give the time for re-grow of the plants. It will results in soil infiltration, accelerated
run off and soil erosion. The soil fertility is developed by action of microorganism.
Overgrazing can reduce their action and also it increases the concentration of
ammonium-N and nitrate-N which are toxic to root at higher concentrations (Czeglédi
&Radácsi, 2005).
Management and Control of Land Degradation with Special Reference to … 173
IRRIGATION PRACTICE
The quality of water using for the irrigation is more important. If the water
has high salinity, it will accumulate and leads to desertification. Irrigational practice
which leads to cracking the lands or bypass flow, by flooding will influence the soil
structure and nitrate leaching. The crack developed during the irrigation may not
close properly, can leave a U-shaped trace and upon drying these cracks can expand,
will cause soil shrinkage.
URBAN SPRAWL AND COMMERCIAL DEVELOPMENT
Urban sprawl is defined as the physical pattern of low-density expansion of
large urban areas mainly into the surrounding agricultural areas (European
Environment Agency, 2006). Urban sprawl is consequence of increasing urban
population. As the urban population increases, the infrastructure requirement like
transportation, water, sewage and facilities such as housing, school, commerce,
health, recreation will also increases (Ujoh et al., 2010). It consumes agricultural
productive areas, so the green vegetation will be replaced by concretes and wastes.
It reduces the biomass production and destroys the productive land, leads to land
degradation. For the development of infrastructure like roads and metro system,
electricity and other requirement will leads to the destruction of fertile land (Geist
& Lambin, 2002). In the developing countries like India, the major issue is lack good
governance and administration in local bodies. Lack of information, keeping system
and traceability of the record, is also an important issue for the governance (Sudhira
& Ramachandra, 2007).
POLLUTION FROM INDUSTRIES
The industrial operation also causes the land degradation. It can be either
from the waste from the industries or the exploitation of the resources. The large
scale commercial farming can cause soil erosion, land salination or loss of nutrients.
Exploitation of the water and land resources is the effect of green revolution. To
increase the productivity and yield, application of chemical fertilizers, different
pesticides causes the contaminated water and land. Whereas intensive agriculture
and irrigation can contributes salination, alkalization and water logging (Indian Ministry
of Finance, 1999). The small industries releasing the waste directly to the open
areas will leads to serious issue in the future leads to environmental pollution. The
waste may contain serious chemicals which can degrade the land fertility and
productivity. The non recyclable compounds like poly bags will destroy the land
capacity of the water intake, if they are dumped off without any care. They remain
for several years. Many industrial wastes like solvents can kills the favorable micro
organism may require to keep the soil fertility.
MINING AND QUARRYING ACTIVITIES
Mining is done for the extraction of the mineral deposit like iron, gold, silver,
etc. and quarrying for generally the granite for construction works. Due to this
174 Aquaculture and Fisheries Environment
excavation process alter the structure of the land, stacking of top soil, loss of soil
due to dumping the mine wastes and also overburden cause lying on the land after
mining. Tailings, the leftover material after purification of the ore like slag, slime,
and leach residues are also cause land degradation (Vagholikar & Moghe, 2003).
Stone and sand quarrying cause the loss of fertile top soil, degradation of forest and
land. Mining also leads to fragmentation of forest and land often because diminishing
the vegetation surrounded. Often the mines may be remote from the general
transportation facility, required new roads construction to mining area, all leads to
land degradation (Singh et al., 2003; Singh & Asgher, 2003).
AGRICULTURAL INTENSIFICATION
Ever demand of the food and reducing agricultural land along with increasing
population, leading to agricultural intensification by using advanced technologies
including high yield crop, fertilization, irrigation, pesticides, etc. has increased the
yield of production from the limited land. The frequent hoeing and plough of the soil
will leads to erosion. The intensive farming by many number crops in year will
cause for nutrient depletion, especially area where the nutrients are limited. So the
use fertilizers are necessary, as consequences the soil become more acidic
(Raut et al., 2010).
EFFECTS OF LAND DEGRADATION
The effects of land degradation includes accelerated soil erosion by wind and
water, soil acidification, soil alkalinisation, soil salination, soil water logging, destruction
of the structure of soil (Eswaran et al., 2001; Scherr & Yadav, 2001; Lu et al.,
2007). Soil erosion is the process of take up, transportation and deposit of soil from
one place to another. The transportation media can be wind, water or ice. The main
causes of increased erosion are industrial agriculture, deforestation and urban sprawl.
Usage of tillage in industrial agriculture will remove the top vegetation and leads to
erosion (Angelsen & Kaimowitz, 2001; Angelsen, 2007). It can be controlled under
sustainable practices like terrace building, conservation tillage practice and tree
planting. Soil acidification is the effect of reducing the pH of soil. This can commonly
by acids such as sulfuric acid, nitric acid, or compounds like aluminium sulfate or
compounds from fertilizer nitrogen like ammonia. The major reason for soil acidity
are from nitrogen leaching process, addition of excess nitrogenous fertilizers and
build up of organic matter. If the water containing high amount sodium bicarbonate
will increases the pH of the soil. Soil salination is a natural phenomenon, the soil
with high level of salt, climate favourable accumulation and can be by human activities
like aquaculture activities, land clearing or salting the road. Soil water logging,
saturation of soil with water is another effect of land degradation. Irrigation can
change the soil structure. The porosity can be blocked by clay during irrigation.
High level of sodium content also can cause change soil aggregation.
Management and Control of Land Degradation with Special Reference to … 175
IMPLICATIONS AND EFFECTS
Reduced Productivity
As the land quality reduced as effect of land degradation the productivity also
reduces. Impacts of change in soil quality like erosion are leads to less productive
land. Water erosion is most common phenomenon which is leading to low productivity
of the land. As result of soil erosion the soil fertility gradually decreases.
MIGRATION
Land degradation will leads to migration of the people from one are to another,
especially the dry area to near place either for short term of long term. It can lead
to suboptimal land-use and further degradation of land. It can also create social,
economic and environmental imbalance.
DAMAGE TO BASIC RESOURCES AND ECOSYSTEMS
Land is a non renewable resource, by degrading it creating damage to the
basic resource and ecosystem by changing the quality of the land, temporarily or
permanently, creating an imbalance to the eco system. The leached nitrogen can
contaminate the water sources can make it as non drinkable as high level of nitrate
or it can leads to development of phytoplankton on excess level, and then reduces
the dissolved oxygen level.
FOOD INSECURITY
Land degradation will leads to reduction in productivity or turn the land in to
non productive land. As the problem is more common in developing countries,
increasing population along with reduced productivity will leads to food insecurity.
LOSS OF BIODIVERSITY
The process like deforestation and desertification process will leads to loss of
flora and fauna. Most of the species cannot adapt in to new modified environment.
Change in pH of the soil can leads to destruction of the microbes in the soil really
needed for the fertilization process of the soil.
ADAPTATION
The person needs to adapt in to the new environment as consequence of land
degradation. The availability of resources such as water, land will be reduced as
result of degradation process.
SOLUTIONS AND REMEDIES
Management of Deforestation
Afforestation: Planting of tree is the best options to make forest in a non
forest land are the one of the best option to reduce the consequences of deforestation.
It can reduce the soil erosion.
Use of timber alternate: Use of mud brick for the construction instead of
timbers for land reclamation.
176 Aquaculture and Fisheries Environment
Eco forest: System which cut only the specific tree required, create minimal
damage to that particular forest area.
Green business: This includes paper recycling and using wood alternatives.
MANAGEMENT ON OVERGRAZING
Management practices like water development, placement of salt and
supplements, fertilizer application, fencing, burning can control the overgrazing. By
control the gap between the grazing and giving time to for re-vegetation also helps
to reduce overgrazing. Keeping the livestock not more than 4 days in paddock, can
reduce over grazing. The density of the livestock in a particular grazing area also
needs to be controlled (Czeglédi & Radácsi, 2005).
MANAGING IRRIGATION
Irrigation system can be controlled like drip irrigation to reduce soil erosion.
Using high and low salt water was most effective in maintaining the productive
capacity of the clay soil. Often high irrigation leads to leach of nutrient and top
fertile soil along with that water. Management of irrigation is an essential factor to
keep the quality of soil (Crescimanno, 2001).
MANAGING URBAN SPRAWL
The urban planning is the most important factor, to control the urban sprawl.
Appropriate government policies can also control the urban sprawling. Policies
appropriate to control the urban sprawling are necessary. Fertile field near by the
urbane area need to be protected by the local government rules, because of the
tendency of converting such land for commercial purpose will bring more income
than agriculture (Ifatimehin & Musa, 2008). So, effective policy is required to control
such usage of fertile land. There should be a proper waste management system
dumping of these waste generated as part of urban sprawling will degrade the land,
can cause soil salinity, acidity and loss of it vegetative properties. By using the
digital technologies like Geographic Information Systems (GIS), mapping and
monitoring will be useful for monitoring purpose for the local authorities and
governments (Sujatha et al., 2000; Haboudane et al., 2002; Thiam, 2003; Wessels
et al., 2004; FAO, 2003). Another possibility is to use System Dynamics (SD)
framework, which capture the stock and flow. Development of models using Cellular
Automate (CA) is helpful to visualize the impact of urban sprawl (Sudhira &
Ramachandra, 2007).
MANAGING MINING AND QUARRYING
The impact can be reduced by proper management of mining process, using
advanced technologies rather than conventional methods. After mining by proper
back filling, spreading the soil back over the top, the land can be reclaimed (Elliott et
al., 2003). The refilled land after mining can be used for planting trees. The top soil
can be stacked if not used and can be used later for plantation. It can be adequately
Management and Control of Land Degradation with Special Reference to … 177
protected from leaching out during raining. The use of geo-textiles, the permeable
fabrics which separate, filter, reinforce, protect or drain the soil, will help the re-
vegetation process (Sharma et al., 2004). Policies for controlling mining activities
depend on the geographical location and threat to the land can be implemented to
control mining and quarrying process.
MANAGING AGRICULTURAL INTENSIFICATION
Agricultural intensification need to be managed properly to reduce the
environmental effect. This can be done through proper education of the farmers.
The intensification is necessary for especially in developing countries for the food
security. It can be adopted with ecological friendly appropriate technologies.
Implementation of integrated pest and nutrient management, policies for
environmental taxes for nitrogen fertilizers, high yielding varieties, terracing, legume
intercropping, contour hedgerows, cover crops, minimum tillage, selection of
appropriate crops, organic and inorganic fertilizer use etc can be done for sustainable
agricultural intensification (Raut et al., 2010).
LAND RECLAMATION
Recovery of land’s productivity, which might have lost during the past or during
the creation of new land from sea or river, is called as land reclamation. The
requirements are land may be damaged due to natural hazards like fire, earthquake,
tsunami etc. or by human activity like poor farming methods. The land with high
water content, waterlogged land, which is not suitable for agricultural activities.
The increasing population in urban coastal cities, where the land scarcity is huge, it
is difficult to find new land. By land reclamation it can increase available arable
land or it expands the carrying capacity, control of overcrowd in urban areas,
economy through new industries (Soni, 2003; Singh, 2002). The world’s largest land
reclamation is done at Dubai, The Palm Jumeirah, 31-square-kilometer island group
costing US$ 14 billion.
India has extensive salinisation, having about 7 million ha of salinised land.
Salinisation is Extensive in the Indus-Ganga Plains of North-western India and in
the States of Haryana, Punjab, Rajasthan and Gujarat. The Western part of this
area (Rajasthan) is arid, and the rivers are intermittent. Smaller but significant
occurrences are found in irrigation areas in southern India. Surface water quality in
north-western India is generally good, but ground water quality is variable. Water
salinity generally increases from north to south and with depth. Very saline water
(16 g/L) can be found below 200 m.
Ground waters of sufficient salinity for inland saline aquaculture are available
in each country discussed, and in very large supply in waterlogged areas on deep
alluvium in Pakistan, north-western India and the North China Plain. When pumped
for vertical drainage or to supplement surface water supply, the water is discharged
to surface drainage systems; evaporation ponds are rarely used in Asia. The
178 Aquaculture and Fisheries Environment
extraction of saline (> 3 g/L) ground water is undesirable because of its contribution
to downstream salinisation of surface water. Inland saline aquaculture could provide
additional income by using water associated with lowering water tables, increasing
water supplies or salt-mining, but from an agricultural and resource management
point of view it appears too risky to encourage deliberate extraction of saline ground
water in inland areas solely for aquaculture.
Researchers have observed that opportunities for large-scale saline aquaculture
using saline ground waters appear limited. Similarly, the use of saline ground water
for aquaculture is likely to have little effect on the extent of land and stream salinity.
There may be small-scale opportunities for farmers to diversify their income sources
and use the income generated to offset the costs of other remedial measures for
land salinisation.
IMPROVING DEGRADED LAND BY WATERSHED RESTORATION IN INDIA
In 1989, World Bank sanctioned a project loan for an amount of US$100
million on integrated watershed management for the hills of northern India. The
project which covered states of Punjab, Himachal Pradesh, Harayana and Jammu
and Kashmir, was executed with the help of personnel from the departments of
agriculture, horticulture, forestry and animal husbandry. Administrative, financial
and technical functions were all vested with the project authority to avoid
compartmental or fragmented solutions to achieve an integrated approach. Funds
were earmarked for training and for participatory on-farm research.
(a) Joint management policy
Watershed-based solutions to land degradation involve the simultaneous
management of private, common, arable and non-arable land resources. Local
communities utilize many different resources but in India forest policy, used to be
remote from the people who were not involved in their management. Experience at
the Central Soil and Water Conservation Research and Training Institute
(CSWCRTI), in Dehradun, has encouraged about 50 per cent of Indian states to
declare a joint forest management policy which is community-friendly or participatory.
(b) People’s participation
In 1978, the CSWCRTI began to introduce resource conservation through
integrated watershed management, involving a mix of structural and vegetative
measures with the help of local communities. Initially, people’s involvement was
low but this was built up and the projects were ultimately handed over to officially-
registered community organisations. The open grazing was eliminated through ‘social’
fencing and biomass productivity was doubled or even tripled. The organisations
operated independently of both government and local authorities, deriving their income
from the sale of grass, harvested water, fuel wood and membership fees. Funds
were spent in maintaining project structures, paving village roads, constructing village
halls and starting up veterinary hospitals. In some cases, they leased government
forest lands to increase their incomes.
Management and Control of Land Degradation with Special Reference to … 179
CAUSES OF MANGROVE DAMAGE AND NEED FOR CONSERVATION
The value of mangroves has gone unrecognized for many years and the forests
are disappearing in many parts of the world. These impacts are likely to continue
and worsen, as human populations expand further into the mangroves. In regions
where mangrove removal has produced significant environmental problems, efforts
are underway to launch mangrove agro-forestry and agriculture projects. Mangrove
systems require intensive care to save threatened areas. So far, conservation and
management efforts lag behind the destruction; there is still much to learn about
proper management and sustainable harvesting of mangrove forests. Even where
efforts have been made to slow the destruction, remaining forests have a number
of problems. In some areas, the health and productivity of the forests have declined
significantly. The causes of these tragic losses differ from habitat to habitat but are
generally tied directly or indirectly to human activities. Individual study is required
to determine the most effective remedial measures. Where degraded areas are
being regenerated, continued monitoring and thorough assessment must be done to
help us understand the recovery process. This knowledge will help us develop
strategies to effectively rehabilitate degraded mangrove habitats over the world.
AQUACULTURE PRACTICES IN DRY LANDS
Aquaculture in dry lands is inherently advantageous to dry land agri-culture
because although aquatic organisms live in water they do not transpire it, so water
losses from aquaculture are predomi-nately from evaporation rather than raised
evapo-transpiration. Also, many more aquatic species than terrestrial crop spe-cies
are tolerant of salinity and even thrive in it. Thus, dry land aquaculture can prosper
on fossil aquifers whose high salinity greatly curtails their use by dry land agriculture.
When dry land aquaculture borrows the technology of dry land greenhouses, water
conservation is even greater than it is in agricultural greenhouses due to zero
transpiration of aquatic organisms. At the same time, dry land aquaculture does not
compete for water with dry land agriculture due to the diver-gent salinity tolerances
of terrestrial plants and aquatic organisms (Kolkovsky et al., 2003). Since dry land
aquaculture is always more economic on land than dry land agriculture, land use as
well as water use efficiencies are high. Thus, dry land aquaculture, like dry land
controlled-environment cash crop agriculture, does not depend on local ecosystem
services and need not cause desertifi-cation.
Dry land aquaculture is based on aquatic animals and plants or some
combination of both. The produc-tivity of aquatic animals is not light and C02
dependent; hence the costs of feeding the animals are greater than those of fertilizing
the plants. However, there is an added cost of water filtration due to the enrichment
of the water by the surplus organic load of animal feed and animal excretions. This
cost can be reduced by integrating animal and plant aquaculture, in which algae
thrive on the animal waste-enriched water or the enriched water can be used for
180 Aquaculture and Fisheries Environment
irrigation of crops. Plant aquaculture is advantageous on animal aquaculture in that
feeding is not required and organic load is not a problem. Also, given that most
aquatic plants are either very small or unicellular, their growth is much faster than
that of terrestrial plant crops and the ratio of harvested to non-harvested biomass of
the crop is much higher than that of terrestrial plants.
Dry land aquaculture of both plants and animals is more advan-tageous than
aquaculture elsewhere due to the abundance of light for aquatic plants and of winter
warmth for both plants and animals. An added benefit is the higher availability and
hence the lower price of land in dry lands than in non-dry lands and the reduced
competition with agriculture on land in the dry lands. Most of the products of dry
land aquaculture are cash crops, such as ornamental fish, high-quality edible fish
and crustaceans, and industrially valuable bio-chemicals produced by micro-algae,
such as pigments, food additives, health food supplements, and pharmaceutical
products.
CREATING LEGAL FRAMEWORK FOR CONSERVATION
In soil conservation the law has far too often been seen only as a means of
enforcing unpopular measures such as the protection of forest and grazing areas.
These measures, which have often deprived the rural poor of their livelihoods, have
become very unpopular with the general public and have almost inevitably failed.
This has led many to the unfortunate conclusion that the use of legislation is
counterproductive in land conservation and rehabilitation programme. Innovative
legislation can offer governments an important tool for promoting conservation. A
thorough review of all relevant legislation is an essential element of a national
conservation strategy. Where necessary, existing legislation should be revised and
new legislation introduced. Emphasis should be placed on the introduction of measures
which will encourage more productive and sustainable forms of land use, and
effective stakeholder participation.
REVIEWING WORKFORCE AND TRAINING
The requirements of staff, training and facilities should all be reviewed as an
important step in the development of a national programme. While doing this, special
attention should be given to:
Training technicians in how to involve rural communities in planning and
managing their own conservation programmes, as well as the latest
conservation techniques;
Incorporating conservation as a vital part of all farmer training courses;
and
Organizing short seminars for administrators to sensitize them to
conservation and the important role that they have in national programmes.
Management and Control of Land Degradation with Special Reference to … 181
The importance of these needs has already been recognized by the Asia Soil
Conservation Network for the Humid Tropics (ASOCON), which has promoted
training for conservation staff in the region and is able to provide information on
request.
RESEARCH NEEDS
As the general approach to land conservation and reclamation changes, there
is a need to identify research needs, particularly adaptive research in conservation
practices. These must be suited to local conditions, easily integrated into existing
farming systems and readily acceptable to the land users because of the tangible
benefits that they offer. Traditional conservation practices often offer a starting
point for research as farmers are inclined to accept new ideas which are based on
already tried practices. There are many well-known traditional conservation practices
in the region, ranging from the use of log contour fences in Papua New Guinea to
bench terracing in Java and a variety of agro-forestry systems in the Philippines
and Sri Lanka. As populations increase and the pressure on the land intensify,
traditional systems need to be adapted to the changing requirements of land users.
Once research priorities have been identified, it is necessary to consider whether
the research is best conducted nationally or regionally. As most countries in the
region have limited facilities and a shortage of trained research workers, it is
necessary to ask regional networks like Asia Soil Conservation Network for the
Humid Tropics (ASOCON), to investigate conservation issues, which is common to
many countries.
DEVELOPING CONSERVATION PROGRAMMES
Once government policy and strategy have been finalized, programmes need
to be developed. These plans should be flexible and designed to be periodically
reviewed and updated. Generally, national conservation plans need to be developed
at three levels as mentioned below:
At the national level, where government policy is combined with physical,
social and economic data to produce a general national conservation
programme for the next 10 to 20 years. This programme should be
published as a formal government document and incorporated in the
national development plan where it forms a framework for subsequent
legislation, administrative action and budgeting for conservation.
At the district or province level, more specific and detailed programmes
need to be developed, based on the national programme but in the form
of rolling multi-year plans which can be reviewed and updated annually.
An important aspect of these plans should be the identification of the
specific inputs from different government and donor agencies.
At the local level, programmes must be framed to the individual
requirements of the community and developed in collaboration with the
182 Aquaculture and Fisheries Environment
communities themselves. Members of the ASOCON network have
already been involved in developing a methodology and planning system
at this level. Once formulated, these local level plans should be referred
back to the district level and provision made for technical support and
any other inputs that may be needed for their implementation.
The predicted increase in the loss of land as a function of sea level rise should
impact both shrimp farming and finfish culture. The adaptation measure
recommended for shrimp farming entails integration Climate Change and Climate
Variability (CCCV) impacts and adaptation responses into the EIA process as well
as the preservation of the mangrove zone between the sea and farm infrastructure.
The adaptation measures for finfish culture include the definition and implementation
of a zoning scheme for cage culture and other aspects of sub-tidal aquaculture.
Climate change and/or climate variability, together with the other stresses on the
environment, produces actual and potential impacts. These impacts trigger efforts
of mitigation, to remove the cause of the impact, or adaptation to modify the impacts.
Climate change generally will exacerbate existing problems including flooding and
degradation of ecosystems.
CONCLUSION
Declining of the productive capacity of the land is a serious global issue as it
affects the social, economical and environmental balances across the globe. Land
degradation can be caused by natural phenomenon, but human induced land
degradation is most dominant cause of climate change. The population growth also
leads to land degradation indirectly. As results of these human activities it can leads
to soil erosion by wind and water, soil acidification, soil alkalinisation, soil salination,
soil water logging, destruction of the structure of soil. The implications of the land
degradation include reduced productivity, migration, damage to basic resources and
ecosystems, food insecurity, loss of biodiversity and adaptation. The land degradations
can be controlled by managing different human activities such as deforestation, use
of timber alternate, eco forest, etc. Managing grazing practices, land management,
irrigation management, control on urban sprawl and control and management on
mining quarrying operations are the few solutions for reduce or prevent land
degradation. Sustainable agriculture & aquaculture intensification can be implemented
to reduce the ecological effect without affecting the productivity. It is necessary to
have local and global policies and regulations to control the land degradation.
Land degradation is driven by the complex socio-political and economic context
in which land use occurs; the same is true of solutions to land degradation. Smallholder
agricultural systems are an important intervention point for measures aimed at
preventing or mitigating land degradation in the developing world. Integrated solutions
that support participa-tion in sustainable land management are needed to achieve
balance in food produc-tion, poverty alleviation, and resource con-servation.
Management and Control of Land Degradation with Special Reference to … 183
Aquaculture has a strong tie with the environment through its prerequisite for
good water quality. Not only can it provide considerable benefits to the community
in terms of jobs and economic opportunities, but it can also act as a sentinel for
some of the less observable effects of human activity that affect our water
catchments. Aquaculture development that is planned with good-practice principles
in mind must be sustainable if it is to be viable. The scope for integrating aquaculture
activities into remedial solutions for salinisation of inland agricultural lands provides
a new frontier for the modern systems approach to agriculture.
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Thesis
Full-text available
The available amount of fresh water for agriculture, and specifically for irrigation, is decreasing all over the world. The quality of irrigation water is deteriorating, and saline/sodic waters are increasingly used in many arid and semi-arid regions of the world. Salinization is closely associated with the process of desertification. Sustainable land management practices are urgently needed to preserve the production potential of agricultural land while safeguarding environmental quality. In cracking soils sustainable management should take into account the occurrence of bypass flow and the influence that land use may have on soil structure and bypass flow phenomena. Measurement of vertical and horizontal shrinkage in confined soil cores was found to be suitable for determining the Soil Shrinkage Characteristic Curve (SSCC) and for incorporating shrinkage in the soil hydraulic parameters/functions determined on confined undisturbed soil samples. An optimization procedure based on multi-step outflow experiments with inverse modelling was developed for determining the soil hydraulic characteristics (HC). The need for accounting for structural porosity and shrinkage processes was recognized on the basis of hydraulic conductivity values determined by the suction crust infiltrometer method and of the SSCC determined on confined soil cores. Analysis of the response of clay soils to ESP values up to 15, showed that the concept of critical threshold needs reconsideration, because increasing soil degradation upon increasing ESP appeared to be a continuum. A major hazard of deterioration of structural and hydraulic properties was recognized even at low ESP values (ESP<5) in dilute solutions. In addition, the major influence that reductions in hydraulic conductivity due to salinity and/or sodicity may have in water transport in the soil-crop system was also documented by application of the LEACHM model. The relevance of bypass flow on the water balance in a Mediterranean climatic context as that occurring in Sicily, was evaluated by application of the FLOCR model. The results showed that bypass flow corresponded with about 70-74% of cumulative yearly rainfall, and that models not accounting for bypass flow may lead to a significant overprediction of crop evapotranspiration and underestimation of the hazard of land degradation and desertification. Results of bypass flow measurements performed in a Mediterranean cracking soil under alternated use of a high salinity solution to distilled water showed that exchange of solutes occurred at the contact surfaces between the macropores/cracks walls and the incoming solution in concomitance with bypass fluxes. These exchanges were effective in determining leaching of solutes and removal of Sodium, and in preventing salinization and sodification in part of the soil volume that is in contact with the roots. Combined use of morphometric and physical techniques made it possible to explore the effect of irrigation on soil structure and bypass flow phenomena of a Sicilian cracking soil under two different irrigation systems, i.e. drip and micro-sprinkler. Different vertical distributions of cracks was found under the two irrigation systems. In agreement with these observations, a different flow behaviour was observed in the laboratory in cylindrical soil cores taken from the irrigated micro-sprinkler field. No bypass flow or lower amounts ofbypass flow were observed in the micro-sprinkler irrigated field compared to the drip irrigation treatment. Chemical dispersion of clay particles and detachment of these particles from the surface and their movement into the cracks were the mechanisms responsible for the partial or total occlusion of the (macro) pores in the micro-sprinkler irrigated field. In conclusion, this study showed that drip irrigation alternatively using high and low salt water was most effective in maintaining the productive capacity of the clay soil being studied, particularly when this water was applied to a cracked soil. Combined use of morphometric and physical methods was necessary to understand the underlined highly dynamic flow behaviour in these complex soils.
Thesis
Full-text available
The available amount of fresh water for agriculture, and specifically for irrigation, is decreasing all over the world. The quality of irrigation water is deteriorating, and saline/sodic waters are increasingly used in many arid and semi-arid regions of the world. Salinization is closely associated with the process of desertification. Sustainable land management practices are urgently needed to preserve the production potential of agricultural land while safeguarding environmental quality. In cracking soils sustainable management should take into account the occurrence of bypass flow and the influence that land use may have on soil structure and bypass flow phenomena. Measurement of vertical and horizontal shrinkage in confined soil cores was found to be suitable for determining the Soil Shrinkage Characteristic Curve (SSCC) and for incorporating shrinkage in the soil hydraulic parameters/functions determined on confined undisturbed soil samples. An optimization procedure based on multi-step outflow experiments with inverse modelling was developed for determining the soil hydraulic characteristics (HC). The need for accounting for structural porosity and shrinkage processes was recognized on the basis of hydraulic conductivity values determined by the suction crust infiltrometer method and of the SSCC determined on confined soil cores. Analysis of the response of clay soils to ESP values up to 15, showed that the concept of critical threshold needs reconsideration, because increasing soil degradation upon increasing ESP appeared to be a continuum. A major hazard of deterioration of structural and hydraulic properties was recognized even at low ESP values (ESP<5) in dilute solutions. In addition, the major influence that reductions in hydraulic conductivity due to salinity and/or sodicity may have in water transport in the soil-crop system was also documented by application of the LEACHM model. The relevance of bypass flow on the water balance in a Mediterranean climatic context as that occurring in Sicily, was evaluated by application of the FLOCR model. The results showed that bypass flow corresponded with about 70-74% of cumulative yearly rainfall, and that models not accounting for bypass flow may lead to a significant overprediction of crop evapotranspiration and underestimation of the hazard of land degradation and desertification. Results of bypass flow measurements performed in a Mediterranean cracking soil under alternated use of a high salinity solution to distilled water showed that exchange of solutes occurred at the contact surfaces between the macropores/cracks walls and the incoming solution in concomitance with bypass fluxes. These exchanges were effective in determining leaching of solutes and removal of Sodium, and in preventing salinization and sodification in part of the soil volume that is in contact with the roots. Combined use of morphometric and physical techniques made it possible to explore the effect of irrigation on soil structure and bypass flow phenomena of a Sicilian cracking soil under two different irrigation systems, i.e. drip and micro-sprinkler. Different vertical distributions of cracks was found under the two irrigation systems. In agreement with these observations, a different flow behaviour was observed in the laboratory in cylindrical soil cores taken from the irrigated micro-sprinkler field. No bypass flow or lower amounts of 11 bypass flow were observed in the micro-sprinkler irrigated field compared to the drip irrigation treatment. Chemical dispersion of clay particles and detachment of these particles from the surface and their movement into the cracks were the mechanisms responsible for the partial or total occlusion of the (macro) pores in the micro-sprinkler irrigated field. In conclusion, this study showed that drip irrigation alternatively using high and low salt water was most effective in maintaining the productive capacity of the clay soil being studied, particularly when this water was applied to a cracked soil. Combined use of morphometric and physical methods was necessary to understand the underlined highly dynamic flow behaviour in these complex soils.
Article
The present paper elaborates the land degradation in terms of soil nutrient loss due to quarrying activities on agricultural land for brick making.
Chapter
This book was first published in 1987 when land degradation was one of the major conservation issues of that decade. Australian scientists were at the fore in awakening world interest in this complex phenomenon and in contributing to debate. This book presents a broad multi-disciplinary perspective on the challenge of problems of degrading land, including the onsite and offsite effects of soil erosion, nutrient loss, and salinisation and on the conservation policies needed to meet the challenge. The volume brings together leading contributors to the field of soil conservation from the natural sciences, from economics and the social sciences, and representatives of farming and conservation organisations. The contributions by natural scientists provide the biological and physical setting to the problem. Chapters on economic, legal and social aspects provide empirical information, together with a conceptual and analytical framework to inform policy makers and to guide them in their choice of policies.
Article
Soil degradation caused by overgrazing is a worldwide problem. The degradation of an overutilized area occurs mainly where animals prefer to spend extra time because of the attractants that are around gateways, water sources, along fences or farm buildings. High grazing pressure decreases plant density which results in changes of the botanical composition of a pasture. The effect that grazing has on a plant depends on the timing, frequency and intensity of grazing and its opportunity to regrow. Overgrazing adversely effects soil properties, which results in reduced infiltration, accelerated runoff and soil erosion. Evidence has been corroborated with high bulk density values, high dry mechanical resistance and low structural stability. The degradation of the landscape may be a short-term phenomenon and recovery is possible after grazing pressures have been greatly reduced. Management practices have been used successfully to improve grazing distribution. These practices include water development, placement of salt and supplements, fertilizer application, fencing, burning, and the planting of special forages which can be used to enhance grazing by livestock in underutilized areas.The authors carried out their grazing experiment on the Hortobágy. The effects of overutilization by livestock on soil properties and vegetation on certain areas of grassland are presented in this paper.
Article
Vulnerability to desertification in Africa is assessed using the information on soils, climate, and the pre­viously evaluated land resource stresses. Desertification is, “land degradation in arid, semi-arid, and dry sub-humid areas resulting from various factors, including climatic variations and human activities”. Excluded in the definition are areas that have a hyper-arid or a humid climate. The GIS Desertification Vulnerability map was coupled to an interpolated population density map to obtain estimates of the number of persons affected by desertification. Desertification processes affect about 46% of Africa. The significance of this large area becomes evident when one considers that about 43% of the continent is characterized as extreme deserts (the desert margins represent the areas with very high vulnerability). Only about 11% of the land mass is humid and by definition is excluded from desertification processes. There are about 2.5 million km2 of land under low risk, 3.6 million km2 under moderate risk, 4.6 million km2 under high risk, and 2.9 million km2 under very high risk. The region that has the highest pro­pensity is located along the desert margins and occupies about 5% of the land mass. It is estimated that about 22 million people (2.9% of the total population) live in this area. The low, moderate, and high vulnerability classes occupy 14, 16, and 11% respectively and together impact about 485 million people. Agro-Science Vol.2(2) 2001: 1-10
Article
This is the first paperback edition, with minor corrections, of the book first published in 1991 (see 91V/04141), exploring the complex relationships between human development and the environment with emphasis on the causes of land degradation. Beginning with overviews of what land degradation is and why it is occurring, the author illustrates the problem in the context of different habitats such as tropical rain forests and other tropical/subtropical forests and woodland, mediterranean woodlands and scrub, wetlands, uplands, islands, and drylands. The impact of human activities through global pollution, soil degradation and erosion, mineral extraction, industrial and urban development, as well as through conservation efforts, are discussed. Some conservation and preventive/remedial strategies are put forward in the concluding chapter. The coverage of the subject is global, but much of this, particularly deforestation and desertification, is concentrated in Third World countries. -J.W.Cooper
Chapter
Today water pollution........................for ecosystems.