The Peruvian anchoveta, once a source of the world's largest single species fishery, declined because of over-fishing and environmental change. Aquatic biodiversity is threatened primarily by human abuse and mismanagement of both the living resources and the ecosystems that support them. Loss of habitats, over-exploitation and introduction of exotic species are the prime hazards. Fish stocks are a renewable resource, but already many of them are strained to the limit.
Over the years, they have suffered from a widespread notion that the seas are inexhaustible, economic pressures that have encouraged overexploitation and, until just over a decade ago, an international regime that gave almost unlimited access to the majority of them. All fishing activities depend on a fragile resource base which, if mismanaged and overexploited, can easily collapse.
Efforts to regulate marine fisheries can be traced back to the late s with the creation in Europe of the Intergovernmental Commission for the Exploration of the Seas ICES. Many fishery bodies for developing and regulating fisheries, in both marine and inland waters, have been established since — nine of them under the auspices of FAO. Despite this appreciation of the threat posed by overfishing, stocks have continued to be exploited at a non-renewable rate. All demersal deep water species such as cod, haddock and pollack are now either fully exploited, overfished or depleted.
Larger pelagic surface water species such as herring, sardines and anchovy, stocks of which can fluctuate greatly from year to year, are in serious need of management. Crustacea such as shrimp, lobster and crab are also overexploited. Only the bivalve molluscs, such as mussels and clams, and cephalopods such as squid and octopus, offer much scope for expanded production. The world fish catch has increased more than fourfold in the past 40 years, but the misuse of modern technology, coupled with government support for otherwise non-economic production, has had a devastating impact on fish stocks.
Fleets using sophisticated fish detection, non-selective nets up to 50 km long and bottom trawls are driving some species to extinction. Production of crustaceans, mostly from aquaculture, has increased dramatically over the past ten years, exceeding 4. The impact of overexploitation of fisheries may be greatest in the developing world. Commercial fishing in tropical waters can often mean valuable foreign exchange for developing nations, but it can also lead to intense competition with declining catch rates for small-scale fisheries, many of which provide fish for local consumers and markets.
Higher fish prices, the result of increased demand exacerbated by overfishing, are making fish unaffordable to an increasing number of poor people. Environmental degradation. To the pressure of exploitation must be added the degradation or destruction of aquatic ecosystems caused by pollution or competing uses. The oceans function as a sink for carbon dioxide, eroded soils, contaminants, fertilizers, human and industrial wastes.
Most urban and industrial activities and, indeed, much of human life, are concentrated close to coastal waters, rivers and lakes. Six out of ten people live in coastal areas, and migration towards them is increasing. The development of intensive aquaculture has, in some cases, damaged coastal ecosystems and water resources, causing conflicts over land use and resources, and even undermining local sources of employment and food.
In parts of Asia, thousands of hectares of rice paddy have been replaced by high-value shrimp farming or had their productivity reduced by salinization caused by neighbouring aquaculture enterprises. In the Indo-Pacific, more than one million hectares of mangrove forests have been converted to aquaculture ponds. Mangroves provide spawning and nursery areas for many marine species and are vital to maintaining ecological balance and biodiversity.
The introduction of exotic fish species can have many unforeseen consequences. The release of the Nile perch in Africa's Lake Victoria is a classic example. Introduced in the late s as a sports fish, its voracity and large size has driven many of the smaller indigenous species to extinction. Some scientists speculate that — species of fish may have been lost. The expanding population of Nile perch is making Lake Victoria one of the most productive lake fisheries in the world, yielding to tonnes per year. But increased productivity may have been achieved at serious ecological and social cost.
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The lake is increasingly providing fish for export rather than local consumption. Lakeside fishing communities have lost species that traditionally provided food and supported the local economy. The long-term impacts remain to be seen, but this example provides a valuable lesson for future introductions and transfers of fish species. Tilapias, consisting of species of the genera Tilapia, Oreochromis and Sarotherodon , have been widely distributed around the world from their original African home. They are now the mainstay of small-scale aquaculture for many poor farmers in the developing world, as well as for enterprises in the developed world.
They are most widely cultured in Asia, particularly China, the Philippines and Thailand. Its aim is to increase food production and income by and for small-scale producers. The GIFT programme has collected strains of tilapia and evaluated their culture and growth in different environments. Scientists have discovered, for example, that tilapia breeds in Asia are deteriorating as a result of generations of inbreeding.
Future breeding efforts must draw on a wider genetic base, incorporating genetic material from Africa. This underscores the importance of future conservation and utilization of Africa's native tilapia breeds. FAO supports comprehensive programmes on fisheries management, focusing on both coastal zones and high seas. It is also committed to international efforts to introduce ecologically safe fishery technologies.
FAO provides technical assistance aimed at environmentally sound aquaculture practices, as well as incorporating aquaculture in rural development planning. To conserve aquatic biodiversity, FAO emphasizes the sustainable use of aquatic resources. Activities include genetic selection programmes in aquaculture; the elaboration of codes of practice for the introduction and transfer of aquatic organisms and on access to genetic resources and biotechnology; and maintenance of a world database on introductions and transfers, as well as a database on species, strain and race identification.
Capture fisheries have reached or may even have exceeded their sustainable yield at million tonnes, leaving a gap between supply and demand which will reach an estimated 20 million tonnes by the year About kinds of finfish are cultured for food, but 85 percent of production comes from carp while tilapias account for much of the remainder.
In the northwestern United States, genetically distinct populations of ocean-migrating fish species are at high or moderate risk of extinction. Approximately 7 species of marine fish have been described from Indonesia, which has over 13 islands and the largest total coastline of any tropical country.
A bout 30 percent of the world's ice-free land surface is forest or woodland. Forested areas of the world today comprise between 3 million and 3 million ha — an area equal to the size of North and South America. According to recent estimates, temperate forests cover approximately 1 million ha in the industrialized countries and another million hectares in non-tropical developing countries.
Tropical forests, both moist and dry, cover an estimated 1 million ha. Forests supply food, fodder, medicine and timber, poles and fuelwood as well as raw materials for industry. The income earned from trees and forests is of vital importance to both rural populations and national incomes.
Food Stores: Using protected areas to secure crop genetic diversity | IUCN
Forests are home for an estimated million people — shifting cultivators and hunter-gatherers — around the world. In the past, the slash-and-burn agriculture practised by forest-dwelling people was sustainable, but population pressures are reducing the land available for shifting cultivation; shorter fallow periods and overuse are turning traditionally sustainable methods into destructive ones. Rural people living in and around forest areas depend on a large variety of forest products for subsistence. Forest foods form a major part of the diet of some population groups in rural areas in developing countries.
They include leaves, seeds and nuts, fruit, roots and tubers, sap and gums, fungi and animals. Forest foods often increase in importance during the hungry season, which reaches its peak just before crops are harvested, and when crops fail. Woody species provide three-quarters or more of the population in developing countries with their primary energy source.
In developing countries, eight times more wood is used for fuel than is logged for industrial purposes. In many areas, fuelwood is being harvested faster than it is being replenished. By the year , nearly 3 million people could face fuelwood shortages. Forests provide vital ecological functions. Their absorption of carbon dioxide and release of oxygen through photosynthesis help control the level of greenhouse gases and provide an atmosphere essential to support life. Forest vegetation helps recycle nutrients. Forest cover also reduces soil erosion by slowing the runoff of water, reducing the hazard of floods and the silting of reservoirs and waterways.
Forests, woodlands and other wilderness areas are increasingly valued as sites of natural and cultural heritage, as well as for education and recreation. Ecotourism is the third most important source of income in Rwanda, for instance, largely because it is home to the mountain gorilla. Non-wood products and services, many of which have long been used by people living in and around forests, are increasingly appreciated as a source of sustainable development. Many food crops and industrial, commercial and pharmaceutical products originated as non-wood forest products.
The economic and social incentives provided by non-wood forest products encourage conservation and offer a defence against the loss of biodiversity. The world's forests are declining at unprecedented rates. Major threats are deforestation and atmospheric pollution. Another threat is the narrowing of the genetic base of tree species as a result of commercial forestry operations. Whereas reforestation of temperate forest lands now exceeds removal of trees, the loss of tropical forests gives cause for concern.
The tropical forests were destroyed at an annual rate of In terms of area, the greatest losses were in Latin America and the Caribbean an average of 7. The causes of deforestation vary from region to region. The most important include: conversion of forest land to agricultural use; excessive use of fuelwood and charcoal; shifting cultivation where fallow periods are too short; unsustainable logging; expansion of urban and industrial areas; and overgrazing and fodder collection.
Poverty is the underlying cause of many of these environmentally degrading activities. Fungi, commonly valued as meat substitutes, supply large amounts of protein and essential minerals. Despite a net increase in the forested area in Europe, pollution and forest fires have caused a severe decline in biodiversity and forest vigour. Forests in Germany and the former Czechoslovakia have been particularly affected.
Less obvious, but equally alarming, is the decline in genetic diversity within forest species in both Europe and North America. This genetic erosion results mainly from deforestation, compounded for a few economically important species by intensive breeding for commercial forestry. FAO estimates that about tree species are endangered in whole or in significant parts of their gene pools. When forests decline or are removed, much more than trees is lost.
Forests harbour many animals and plants that depend on their environment for survival. Many of these species, their potential value to society and their ecological importance have yet to be discovered. Untapped treasures include possible crops, pharmaceuticals, timbers, fibres, pulp, soil-restoring vegetation, petroleum substitutes and countless other products and amenities.
Landraces are generally less productive than commercial cultivars, although in recent years, they have become important as sources of genetic variability in the search for genes for tolerance or resistance to biotic and abiotic factors of interest in agriculture [ 5 ].
The genetic diversity observed across landraces is the most important part of maize biodiversity, and local races represent an important fraction of the genetic variability exhibited by this genus. However, few agronomic and genetic data exist for such collections, and this scarcity has limited the use, management and conservation of this germplasm. In addition, a few improved genotypes with narrower genetic variability are quickly replacing maize landraces [ 6 ]. Zeven opined that landraces have played a fundamental role in the history of crops worldwide, in crop improvement and agricultural production, and they have been in existence since the origins of agriculture itself.
During this time they have been subject to genetic modification through abiotic, biotic and human interactions. For centuries, crop landraces were the principal focus for agricultural production [ 7 ]. Farmers sowing, harvesting and saving a proportion of seed for subsequent sowing over millennia have enriched the genetic pool of crops by promoting intraspecific diversity [ 8 ].
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This cycle remained current until the dawn of formal plant breeding and the generation of generally higher-yielding cultivars that subsequently replaced many traditional landraces [ 7 , 9 , 10 ]. The origin of landraces encompasses both the temporal and spatial components of where landraces were first developed. They landraces have a relatively long history, significantly more than the ephemeral lifespan of modern cultivars. Nevertheless, few are explicit about the amount of time a landrace must be grown to be considered a landrace.
Hawkes [ 17 ] opined that landraces are associated with one specific geographical location, in contrast to cultivars which are bred remotely, trialed in several locations and subsequently cultivated in diverse locations.
However, migrations seed flow of established landraces from their region of origin to new regions have also occurred as local informal variety introductions. Zeven [ 3 ] proposed two types of landraces: autochthonous landraces cultivated for more than a century in a specific region and allochthonous a landrace that is autochthonous in one region introduced into another region and becoming locally adapted. Continuity and individual cultivation and discontinuity and collective cultivation are both significant. Individual farmers commonly lose and recover landraces as a result of their management of a dynamic portfolio of landraces [ 19 ] and seed replacement [ 20 ] and because of various stochastic events such as drought, floods, pests and diseases.
In fact, several papers have highlighted the relevance of seed exchange for the maintenance of landraces [ 20 , 21 , 22 ]. Such localized farmer exchange activities may help to define and ensure continuity of a landrace. It is generally accepted that farmers, gardeners and growers select and develop landraces [ 12 , 13 , 14 , 15 , 17 , 26 ], while formal plant breeders select and develop cultivars Figure 1.
However, even this division is not as clear as it first may appear if other considerations are included. Examples of these are shown in vegetables that present special traits such as enormous size, developed by growers in the UK. The situation concerning the involvement of landraces in participatory plant breeding is interesting, as Maxted [ 28 ] noted that care should be taken to ensure the security of the locally adapted genetic diversity or the former landrace could no longer be regarded as a landrace. Here, the decision over whether the former landrace may still be regarded as a landrace as described by Almekinders and Elings [ 29 ] depends on the degree of breeding and the quantity of external germplasm introgressed with the original landrace; the more of either the less the entity could be regarded as a landrace.
Certainly, this would be the case for participatory varietal selection programs where external germplasm is introduced into an area and suitable material is selected by local farmers; even if the new germplasm is managed by the farmer in a manner usually associated with traditional farming and landrace maintenance, the use of the term landrace would be inappropriate. Simmonds [ 30 ] and Allard [ 31 ] further explained that modern professional crop improvement is based on the Darwinian theory of evolution through selection and the genetic mechanisms of evolution developed by Mendel, Johannsen, Nilsson-Ehle, East and others.
Frankel and Bennett [ 9 ] used as a reference point the 19th century when conscious, individual plant selection commenced. However, the fact that the history of crop improvement is different for each crop is also an important element to be considered [ 3 ]. Combining these considerations, formal crop improvement is understood as the application of genetic principles and practices to the development of cultivars by both classic breeding techniques selection and hybridization as well as more recent technologies biotechnology, molecular biology, transgenics within a crop improvement program.
In fact, it is argued that inclusion of landraces on the UK National List is likely to promote their cultivation and thus conservation [ 33 ]. Landraces may therefore be more easily defined as being crop varieties which do not result in the first instance at least from formal crop improvement programs, in contrast with modern cultivars which have resulted directly from these programs Figure 1. Despite this improved clarification, there remains confusion as regards the effect of crop evolution on landraces.
Crop evolution is not a linear process, and there are different points of view of the position occupied by landraces in relation to their wild relatives, on the one hand, and cultivars, on the other. Some authors such as Marchenay [ 34 ] suggested that some landraces exist on the borders of cultivation, not having been fully domesticated and might be better considered as ecotypes. Landrace must be intrinsically highly genetically diverse and recognized as a distinct entity via common-shared traits.
These traits will allow the distinction of one landrace from another or from modern cultivars for the same crop. They will sometimes give rise to landrace names, but at other times, names may be determined by other factors such as use or origin. However, this characteristic may be difficult to be applied universally as landraces identified on the basis of common names can be misleading because of non-associated synonyms and homonyms. Many disparate landraces may be named after their early flowering capability or seed color, for example. A landrace may be recognized by different names in different countries or communities [ 36 ], or conversely quite different landraces can be designated with the same name [ 14 ].
These factors contribute to one of the main problems associated with landraces, namely, their consistent identification and the determination of which traits can be consistently used to define the identity of a specific landrace. The characteristics of landraces in relation to the magnitude of allelic and genetic diversity in contrast to cultivars are considered to be significantly more genetically diverse [ 37 ]. The former is generated by heterogeneity in space and reproductive isolation, while the latter is generated by heterogeneity in time associated with both short-term variations between seasons and by longer-term climatic, biological and socio-economic changes.
In contrast however, Sanchez [ 41 ] when evaluating the genetic diversity of maize landraces of Mexico found that some landraces had very low levels of genetic diversity, and it was suggested that comparatively low diversity may be more associated with selfing crops. A similar picture is provided by Tibetan barley landraces which proved to be much less diverse than modern barley cultivars due possibly to their relative geographic isolation, their relatively recent introduction to Tibet and the fact that they have been subject to very little natural or man-made selection [ 43 ].
Therefore, the dynamics of genetic diversity and changes over time of the genetic structure of landraces are likely to be crop specific. It is also likely to be associated with the mode of fertilization self- versus cross and propagation sexual or asexual , which has over time resulted in genetic bottlenecks, varying outcrossing rates, recombination and gene flow.
Landraces are generally adapted to local environment. Bennett [ 44 ] made the assumption that landraces are more suited to cultivation in particular locations than highly bred cultivars that are bred for cultivation in the most common environmental conditions. Inevitably, cultivars will be less suited to grow in suboptimal conditions and therefore have less of a competitive advantage in marginal environments where the local landraces are likely to have an adaptive advantage.
Food Stores: Using protected areas to secure crop genetic diversity
These local conditions may be defined as abiotic e. Several studies have demonstrated the relationship between landraces and local adaptation, for example; Frankel [ 8 ] and Brown [ 39 ] discuss landrace adaptation to marginal conditions associated with climatic, soil and disease stress. The evolution of local adaptation over millennia in these stressed environments ensures yield stability even in extremely adverse years. In this sense, Zeven [ 27 ] considers yield stability to be a principal characteristic of landraces.
However, even though there are numerous references to a specific relation between a landrace and local environmental conditions, there are exceptions. In this sense, some authors consider that local adaptation can comprise both wide adaptation in certain landrace characters and narrow adaptation in others.
Traditional farming systems have often been considered beneficial reservoirs of landraces and intra-crop diversity [ 45 ]. Traditional farming systems involve traditional cultivation, storage and use practices, and integrated with these practical skills, traditional knowledge about landrace identification, cultivation, storage and uses is incorporated.
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Each has shown the role of farmers for the creation and maintenance of a landrace. This indicates that landraces are more inherently dynamic than cultivars as they are maintained through repeated cycles of sowing, harvesting and replacing seed selection by farmers [ 49 , 50 ] within complex informal systems. However, it is also important to consider that traditional farming systems are themselves also dynamic and that the frontier between them and other farming systems is not well defined.
As such, traditional farming systems are subject to change, incorporating in some cases modern cultivars into their systems, growing them alongside landraces of the same species [ 51 ]. Chapter 4: Exploitation of Provides a both practical and theoretical introduction to the techniques of in situ conservation of plant genetic resources.
Highlights the different levels of biological organisation at which conservation is being addressed - the gene, the species and the community. Books Below is a selection of useful books that provide scientific and background information on assessment and conservation actions targeting biodiversity conservation. Publication Year : Wild relatives of cultivated plants in India Authors : Singh, A. Voluntary guidelines for the conservation and sustainable use of crop wild relatives and wild food plants Authors : FAO Publication Year : Wild relatives of crops plants in India - collection and conservation Authors : Pandey, A.
Wild relatives of cultivated plants in India This book is a compilation of taxa related to cultivated plants of economic importance in India, based on the literature of over the past six decades. Authors : Pradheep, K. Agrobiodiversity Conservation: Securing the Diversity of Crop Wild Relatives and Landraces Based on the conference 'Towards the establishment of genetic reserves for crop wild relatives and landraces in Europe', this book is the cutting Authors : Maxted, N.
Conserving Plant Genetic Diversity in Protected Areas Conservation in protected areas has focused on preserving biodiversity of ecosystems and species, whereas conserving the genetic diversity contained Authors : Iriondo, JM. Crop Wild Relatives and Climate Change Crop Wild Relative and Climate Change integrates crop evolution, breeding technologies and biotechnologies, improved practices and sustainable Authors : Redden, R. Predictive characterization of crop wild relatives and landraces: Technical guidelines version 1 Predictive characterization methods use ecogeographical and climatic data derived from the specific location of a collecting or observation site, to Authors : Thormann, I.
Establishment of a Global Network for the In Situ Conservation of Crop Wild Relatives: Status and Needs The objective of this study is to provide sufficient baseline information for allowing decision-makers to strengthen efforts for the in situ Authors : Bilz, M. Preserving diversity: a concept for in situ conservation of crop wild relatives in Europe This document presents a concept for in situ conservation of CWR the Concept to guide EU and national policy development which can be used as a Regeneration of Seed Crops and their Wild Relatives The ex situ conservation of plant genetic resources is of vital importance to contribute to long-term global food security.
Authors : Engels, J. Authors : Khanjyan, N. Cultivated Plants and Their Wild Relatives This book affords valuable insight into the views on the origins of our crop plants. Authors : Zukovskij, P. Beta maritima: The Origin of Beets The book is dedicated to Beta maritima, a single species of the genus Beta and progenitor of various cultivated relatives known as sugar beet, garden Authors : Biancardi, E. Perspectives on biodiversity : case studies of genetic resource conservation and development This book presents case studies presents biodiversity and genetic resource conservation in a broad and unique context.
Authors : Cohen, J. Plant Genetic Resources and Climate Change This book presents contributions from 34 scientists from all over the world, exploring some of the latest perspectives about how plant genetic Authors : Jackson, M. Authors : Reid, W. Gene flow between crops and their wild relatives This comprehensive volume provides the scientific basis for assessing the likelihood of gene flow between twenty important crops and their wild Authors : M.
Carmen de Vicente, Meike S. Andersson, Norman C.