This chapter discusses biodiversity, a term used by conservation biologists to refer to the complete range of species and biological communities on Earth, as well as the genetic variation within those species and all ecosystem processes. By this definition, biodiversity must be considered on at least three levels: species diversity, genetic diversity, and ecosystem diversity. Species diversity reflects the entire range of evolutionary and ecological adaptations of species to particular environments. Genetic diversity is necessary for any species to maintain reproductive vitality, resistance to disease, and the ability to adapt to changing conditions. Meanwhile, ecosystem diversity results from the collective response of species to different environmental conditions. Biological communities found in deserts, grasslands, wetlands, and forests support the continuity of proper ecosystem functioning, which provides crucial services to people, such as water for drinking and agriculture, flood control, protection from soil erosion, and filtering of air and water.
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Chapter
What Is Biodiversity?
Chapter
The Rise of Conservation Biology
This chapter discusses the rise of conservation biology. Conservation biology is an interdisciplinary field that brings together experts from the natural sciences, social sciences, humanities, and economics as well as practices from natural resource management for a common purpose: to protect Earth's biodiversity. The field has three primary goals: to investigate and describe the full variety of life on the planet; to evaluate and predict the effects of human activities on biodiversity; and to develop practical solutions to protect and manage biodiversity sustainably. Since emerging as a distinct field in the mid-1980s, conservation biology has grown dramatically. The chapter traces the origins of conservation before looking at contemporary conservation biology and structured decision-making.
Chapter
Defining Conservation Biology
This chapter provides a background of conservation biology. Human activities are causing the extinction of thousands of species both locally and globally, with threats to species and ecosystems accelerating due to human population growth and the associated demands for resources. Conservation biology is a field that combines basic and applied disciplines with three goals: to describe the full range of biodiversity on Earth; to understand human impact on biodiversity; and to develop practical approaches for preventing species extinctions, maintaining genetic diversity, and protecting and restoring ecosystems. It rests on a number of underlying assumptions that are accepted by most professionals in the discipline: biodiversity has value in and of itself; extinction from human causes should be prevented; diversity at multiple levels should be preserved; science plays a critical role, and scientists must collaborate with nonscientists to achieve their goals. Ultimately, the conservation of biodiversity has become an international undertaking.
Chapter
An Agenda for the Future
This chapter reflects on the future of conservation biology. Protecting biodiversity presents several challenges. To address these problems, there is a need to change many policies and practices. Recent evaluations suggest that reaching international goals for conservation and sustainability is possible but will require major shifts away from “business as usual” practices in production, management, and valuing biodiversity. Changes must occur at the local, national, and international levels and will require action on the part of individuals, conservation organizations, and governments. Conservation biologists must demonstrate the practical value of the theories and approaches of their discipline and actively work with all components of society to protect biodiversity and restore the degraded elements of the environment. To achieve the long-term goals of conservation biology, practitioners need to become involved in conservation education and the political process.
Chapter
Ecosystem Services and Human Wellbeing
This chapter highlights the importance of conservation for human wellbeing. Nature provides us with ecosystem services vital to our health and wellbeing. However, these services have been taken for granted until now. There is a relationship between biodiversity and ecosystem service delivery; loss of biodiversity leads to losses in the ecosystem service, both in its level and its reliability. Traditionally, nature has been valued at zero, hence decision-makers rarely opt for nature conservation rather than using land for other purposes. It is vital that we value ecosystem services correctly and fully so that the real cost of their loss is realized. Often when the full costs and benefits are assessed, nature conservation turns out to be the most cost-effective and valuable option.
Chapter
Metagenomes: Genome Analysis of Communities
This chapter introduces the relatively new field of metagenomics, in which genomic information is extracted directly from communities of organisms living in their natural environments and reveals evidence for their interdependence and co-evolution. It demonstrates how genome analysis can be extended beyond individuals or single populations to study entire communities. It considers metagenomics that analyse genome information extracted directly from organisms living in their native environments to address questions of biodiversity and community structure. The chapter refers to the study on metagenomes, which provides a powerful lens through which to view the otherwise invisible world of many microbial communities. It also mentions how metagenomics involve the interplay of the Five Great Ideas of Biology and many more connections that are likely to be found by subsequent experimentation.
Chapter
Why are there so many species in the tropics?
This chapter discusses tropical diversity. Biodiversity varies enormously from region to region. Probably the most impressive geographical pattern of biodiversity is the decline in species richness from the tropics towards high latitudes. However, even the most fundamental questions about why this pattern exists are not fully answered. Proposed explanations for the latitudinal diversity gradient (LDG) can be classified into historical (based on the accumulation of diversity through time) and ecological (based on current environmental conditions). An underlying assumption of historical explanations is non-equilibrium diversification: diversity is still increasing through evolutionary time. Meanwhile, ecological explanations assume equilibrium dynamics: diversity has levelled off to a 'carrying capacity'. Fossil and phylogenetic data provide complementary approaches to testing hypotheses about large-scale geographical patterns in diversity, each with its own strengths and weaknesses.
Chapter
Conservation
This chapter focuses on the concept of conservation in zoos. Conservation of endangered species is one of the major goals of accredited zoos. The chapter defines conservation biology as the study of methods for maintaining biodiversity. It highlights the role of zoos in the conservation of biodiversity by referencing maintenance of captive stocks, support for in situ conservation, education, and research. The chapter differentiates between ex situ and in situ conservations. It lists the frameworks for zoo conservation such as the World Zoo and Aquarium Conservation Strategy (WZACS). The chapter presents reintroduction as one of the key goals of the many captive management programmes.
Chapter
The State of Our Planet
This chapter provides an overview of the current state of biology on our planet. It establishes some basic facts about the forms of environmental change that are occurring across the globe as a result of human domination of the planet and the subsequent impact that these changes are having on biodiversity. The chapter begins with the state of the human species, emphasizing gains that have allowed our species to be successful, while also highlighting the social inequalities that prevent many from having a good quality of life. It then reviews the state of our global environment, and discusses how human gains for some have come at a cost to the environment. Finally, the chapter looks at the state of biodiversity, including biodiversity losses that are occurring as a result of environmental change.
Chapter
Invasive Alien Species
This chapter studies the causes and consequences of invasive alien species (IAS), as well as the methods to manage and mitigate their impacts. A native species (or indigenous species) is one that occurs within its natural range (past or present) and that does so in the absence of dispersal that is assisted, either directly or indirectly, by humans. In contrast, an alien species (also called exotic, foreign, introduced, nonindigenous, or non-native species) is one that occurs outside of its natural range (past or present) and beyond its natural dispersal abilities, assisted in some way by human activities. Alien species are distinguished from IAS based on their impact. The spread of IAS has become a global problem involving nearly every major group of species. The chapter then looks at the impacts of IAS on biodiversity, ecosystems, and economies, including their potential positive values.
Chapter
Climate Change
This chapter reviews how modern anthropogenic climate change impacts biodiversity and how conservation biologists can mitigate these effects. Anthropogenic climate change is a general term that refers to a suite of abiotic variables that are changing simultaneously across the planet as a result of human activities. Each year, thousands of scientific papers are published that advance our understanding of how the averages, ranges, variability, frequency, predictability, and seasonality of the abiotic variables that regulate Earth's climate are changing across the globe. The main governing body charged with summarizing this literature is the Intergovernmental Panel on Climate Change (IPCC). The chapter then considers the predicted impacts of climate change on biodiversity, the impacts that have been documented to date, and the management strategies available to practitioners to mitigate the impacts of climate change.
Chapter
Community and Ecosystem Conservation
This chapter examines community and ecosystem conservation. The primary tool used for conservation of whole communities and ecosystems is the protected area. A protected area is a clearly defined geographical space that is recognized, dedicated, and managed to achieve long-term conservation of nature and its associated ecosystem services. The concept of protected areas has been around for centuries, but the establishment of protected areas for the purpose of conserving whole ecosystems and their biodiversity is a relatively new concept that began with establishment of national parks. The chapter begins by outlining the classification and global status of protected areas. It then reviews the approaches used to select protected areas, as well as the effectiveness of protected areas for conservation.
Chapter
Biodiversity and Ecosystem Services
This chapter focuses on biodiversity and ecosystem services. Ecosystem services can be defined as ‘nature's contributions to people’. They represent the plethora of benefits that humans receive from both natural and managed ecosystems, including things like the production of consumable goods, non-consumable services, and cultural services. We could just as well define ecosystem services as the collection of biological processes that are required to sustain human life and provide a good standard of living on Earth. Despite their indisputable importance, many people do not know about ecosystem services; nor do they understand or appreciate their value. The chapter then looks at the history and types of ecosystem services. It also considers the biotic control of ecosystem services before examining ecosystem markets and payments for ecosystem services.
Chapter
Habitat Loss, Fragmentation, and Degradation
This chapter describes habitat loss, fragmentation, and degradation. Habitat loss poses the greatest threat to the variety of life on this planet today. It refers to complete elimination of habitats, along with their biological communities and ecological functions. Habitat loss usually results from the conversion of natural or semi-natural habitat into human-dominated habitat. Ultimately, it has been identified as the leading cause of population decay for most wildlife, and it is responsible for nearly 50 percent of all threatened mammal, bird, and amphibian species on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. Meanwhile, habitat fragmentation refers to the process by which larger, continuous habitats become subdivided into a greater number of smaller patches. Finally, habitat degradation refers to a suite of human activities that make the remaining habitat patches in a landscape less conducive to life, in turn eroding biodiversity.
Chapter
Biodiversity, Ecosystem Services, and Climate Change
This chapter covers the interplay between biodiversity, Ecosystem Services (ES), and climate change. It discusses how healthy biodiversity will help people tackle threats from climate change, referring to the significance of traditional nature reserves and protected areas. Moreover, ES and Nature Based Solutions are being used increasingly to highlight ways in which nature helps to make human life both possible and worth living. The chapter explains the provisioning of ecosystem services, particularly agriculture, forestry, and fisheries. It shows that attempts to protect the essential biodiversity needed to maintain and strengthen future ES in the face of climate change will depend on wide and prolonged community involvement.
Chapter
The Tidelands
Rocky Shores, Soft-Substratum Shores, Marshes, Mangroves, Estuaries, and Oyster Reefs
This chapter tackles the habitats formed in tidelands, which primarily involve rocky shores, soft-substratum shores, marshes, mangroves, estuaries, and oyster reefs. Most ecological processes operate within a strong physiological gradient, from a marine to a terrestrial environment in each tidal cycle. Meanwhile, high nutrient inputs and the removal of predators have created ecological instability. Since oysters occur in reefs, which are structures that increase local biodiversity, their feeding and biodisposition may strongly affect the overlying water column and nitrogen cycling in some estuaries. The chapter shows how pollution, disease, and overexploitation of oysters have resulted in widespread degradation of oyster reefs throughout the world.
Chapter
Biodiversity and Conservation of the Ocean
This chapter looks at the notion of biodiversity and the conservation of the ocean. It explores patterns of biological diversity from the broader perspectives of evolution, extinction, and biogeography. Regional variation in geography and climate influences the origin of species, and also the degree of geographic structuring of the world into assemblages of species. The chapter then elaborates on factors of diversity, speciation, extinction, and biography in the ocean. It explains how many marine invasions are facilitated by human transport, referencing the subsequent local extinctions and homogenization of marine biot after the introduction of new species. Thus, conservation genetics play a role in identifying both species and genetically distinct populations.
Chapter
Restoration Ecology
This chapter discusses ecological restoration, which is the practice of re-establishing populations, ecosystems, and landscapes that include degraded, damaged, or even destroyed habitat. The establishment of new communities on degraded or abandoned sites provides an opportunity to enhance biodiversity and can improve the quality of life for the people living in the area. Restoration ecology can also provide opportunities for scientists to learn more about ecological processes and for the public to be involved in conservation efforts. Restoration projects begin by eliminating or neutralizing factors that prevent the system from recovering. Then some combination of site preparation, habitat management, and reintroduction of original species gradually allows the community to regain the species and ecosystem characteristics of designated reference sites. The chapter then considers biological control, bioremediation, and compensatory mitigation or biological offsetting.
Chapter
The Value of Biodiversity
This chapter examines the value of biodiversity, considering how ecological economics is developing methods for valuing biodiversity and, in the process, providing arguments for its protection. Benefits humans derive from nature are called ecosystem services, which can be described and quantified in terms of their use value. Direct use values are assigned to products harvested from the wild. Indirect use values can be assigned to aspects of biodiversity that provide economic benefits to people but are not harvested during their use. Meanwhile, the option value of biodiversity is its potential to provide future benefits to human society, such as new medicines, industrial products, and crops. Biodiversity also has existence value, which is the amount of money people and their governments are willing to pay to protect species and ecosystems without any plans for their direct or indirect use. The chapter then looks at the concept of environmental ethics.
Chapter
Threats to Biodiversity: Habitat Change
This chapter assesses three of the major threats to biodiversity: habitat destruction, habitat fragmentation, and environmental degradation and pollution. All of these threats result from the use of the world's natural resources by an increasing human population. Habitat destruction particularly threatens rain forests, wetlands, coral reefs, and other species-rich communities. Habitat fragmentation is the process whereby a large, continuous area of habitat is both reduced and divided into two or more fragments. It can lead to the rapid loss of some of the remaining species because it creates barriers to the normal processes of dispersal, colonization, and foraging. Meanwhile, environmental pollution eliminates many species from ecosystems even where the structure of the community is not obviously disturbed. It results in pesticide biomagnification; contamination of water with industrial wastes, sewage, and fertilizers; and air pollution resulting in acid rain, excess nitrogen deposition, photochemical smog, and high ozone levels.
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