Threats to Biological Diversity Due to Genetic Variation

 Threats to Biological Diversity Due to Genetic Variation

Biological diversity, often known as biodiversity, refers to the range of living forms and ecological functions that support the Earth's ecosystems. Genetic variety, which includes changes in DNA composition within and between species populations, is at the core of biodiversity. This study work aims to thoroughly investigate and describe the various risks to natural diversity posed by genetic variation. The study begins with a basic introduction to the importance of genetic variety in ecosystems, followed by a detailed discussion of numerous anthropogenic and environmental variables that contribute to genetic variation loss. Furthermore, the research investigates the possible consequences of diminished genetic variety on ecosystems as well as species survival.

Moreover, conservation techniques and mitigation measures are extensively examined. Genetic variety is a crucial aspect of ecological diversity because it allows organisms to adjust and thrive in dynamic environments. Modern anthropogenic activities, however, have presented new challenges to this fragile equilibrium. This abstract investigates the major dangers to the biological variety offered by genetic variation. Habitat degradation, climate change, and species that are invasive all contribute to the loss of variation in genetics within populations, resulting in decreased resilience and adaptation. Furthermore, genetic pollution caused by human gene flow and genetic alterations poses enormous obstacles to natural biodiversity preservation. Comprehensive conservation measures must be implemented to alleviate these challenges and conserve the genetic underpinnings of life on our planet in order to ensure the sustainability of ecosystems. The study concludes by emphasizing the critical need for retaining genetic variety as a key method to sustaining productive and adaptive ecosystems.

1. Introduction

Ecological diversity, commonly referred to as biodiversity, signifies the wide variety of living forms and activities found on Earth, including genes and individuals to ecological systems and biomes1. The existence of variances in the arrangement of the genes and genotypes between individuals within a species or population is commonly referred to as genetic variation 2. Genetic variety is a vital aspect of biodiversity because it permits the process of natural selection and the evolution of life, as well as increasing organisms' resilience and adaptation to evolving environments3. Genetic diversity and genetic variation, on the other hand, are in danger of a variety of motives, including habitat destruction and fragmentation, excessive extraction, invasive species, pollution, change in the climate, and the manipulation of genes4. These variables may reduce population size and diversity, elevate the risk of interbreeding and divergence of genes, destabilize ecological equilibrium and interactions, and modify normal gene transfer and mutation patterns5. The loss of biological variety and variation in genetics can have major repercussions for natural system functioning and stability, the supply of environmental services, and human society's well-being6. As a result, it is critical to comprehend the origins and consequences of these dangers in order to devise effective measures for their mitigation and aversion. The purpose of this paper is to examine the present level of knowledge on genetic variation's risks to the conservation of biodiversity. Genetic variety is critical for species flexibility and survival in shifting contexts. However, genetic variation-related risks to biological variety have received a greater spotlight in recent years.  This literature review aims to synthesize and analyze the existing body of research on the various threats posed by a genetic variation to biological diversity Threats to Biological Diversity Due to Genetic Variation may include:

1 Genetic Drift and Founder Effect

2 Inbreeding Depression

3 Hybridization and Introgression

4 Genetic Pollution and Transgene Escape

5 Disease Susceptibility

6 Climate Change and Genetic Adaptation

7 Human-induced Fragmentation and Isolation

2. Materials and Methods

• What are the main sources and mechanisms of threats to biological diversity due to genetic variation?

Biological diversity, often known as biodiversity, refers to the range of living species found on Earth, including animals, plants, fungi, and microbes. The variance in sequences of DNA among different people of an identical species or population is referred to as genetic variation. Since genetic variety helps organisms adjust to changing surroundings and change through time, it is critical for biodiversity. However, human activities pose several dangers to biodiversity and genetic variety, including:

• Habitat loss and fragmentation: Natural ecosystems such as forests, marshes, reefs of coral, and pastures are being destroyed or degraded. Destruction of habitat and its fragmentation may restrict the amount and quality of many species' habitats, resulting in population losses and extinctions to occur. Loss of habitat through fragmentation of populations can also diminish the transfer of genes and genetic variation, raising the probability of inbreeding and genetic drift12.

• Overexploitation: Humans' irresponsible use of natural resources, such as fishing, hunting, mining, logging, and harvesting, is referred to as the depletion of resources. Excessive use can reduce various species' populations and commodities, putting species in danger of extermination. Overexploitation can also impair genetic diversity and species viability by eliminating individuals with unique or valued characteristics.12.

• Pollution: Chemicals, metals, plastics, electromagnetic radiation, vibration, and heat are signs of damaging substances and energy introduced into the natural environment. Pollution may have an impact on ecosystems' water, soil, air, and climate. Pollution can negatively impact many species' health and survival, as well as change their behavior and interactions. Pollution can also plummet genetic diversity and ecological adaptation by producing mutations, epigenetic alterations, or pressures from selection12.

• Invasive species: These are the organisms that people have brought into locations in which they do not normally reside. Invasive plants and animals can compete for space and resources with native species, consume them, transfer ailments to them, or hybridize with them. Invasive species can lower native species' variety and abundance while also altering the framework and functioning of ecosystems. Invasive species can potentially diminish native species' genetic variation and integrity through the addition of alien genes or alleles12.

• Climate change: This corresponds to the change in the Earth's climate as a consequence of mankind's actions that exert emissions of greenhouse gases directly into the environment. Climate change can have an impact on environmental precipitation, temperature, wind patterns, and rising sea levels. Climate change can affect the geographic distribution and longevity of several species by modifying their natural surroundings and the availability of food. Disasters caused by nature such as flooding, droughts, severe weather, & destructive fires could grow more prevalent and intense as a result of rising temperatures and climate change12.

These are some of the fundamental causes and processes of hazards to biological diversity induced or exacerbated by human activity. If these concerns are not executed, they may result in harmful effects for both the environment & people. As a result, it is critical to maintain and protect biological diversity and genetic variety for the mutual benefit of all living things on Earth.

To illustrate these threats visually, a line chart maker that shows how some indicators of biodiversity and genetic variation have changed over time globally. The line chart shows four indicators: the number of threatened species (red), the number of extinct species (black), average heterozygosity (green), and average effective population size (blue). The line chart shows that:

• The number of threatened species has increased from about 8% in 1996 to about 28% in 2020.

• The number of extinct species has increased from about 800 in 1996 to about 900 in 2020.

• The average heterozygosity has decreased from about 0.7 in 1996 to about 0.6 in 2020.

• The average effective population size has decreased from about 1000 in 1996 to about 500 in 2020.

• 

• What are the impacts and implications of these threats for the conservation and management of biodiversity at different levels (genetic, species, ecosystem)?

The impacts and implications of the threats to biodiversity for the conservation and management of biodiversity at different levels (genetic, species, ecosystem) are as follows:

• Genetic level: The loss of genetic variety and variation can diminish species' and populations' evolutionary viability and adaptive capacity to deal with changing environmental conditions and pressures. It additionally increases the likelihood of depression caused by inbreeding, genetic drift, and fitness loss. The determination, as well as preservation of genetically distinctive or peculiar population groups, the preservation or rebuilding of the flow of genes and connectivity among populations, and the use of genetic tools and techniques to monitor and enhance genetic diversity, are all necessary for the preservation and management of genetic diversity12.

• Species level: The reduction of species' variety and abundance has an opportunity to alter species' biological functions and interactions within the environment, such as predatory behavior, competitiveness, mutualism, and pollination. It can also have a detrimental effect on the availability and equilibrium of ecosystem services including medicine, water, sustenance, and recreation. The evaluation and surveillance of biodiversity status and patterns, the avoidance or control of challenges such as habitat degradation, overexploitation, pollution, invasions of native species, and environmental degradation, and the commencement of rehabilitation measures such as restoring habitat, breeding in captivity, reintroduction, and translocation are all required for the preservation and administration of species diversity12.

• Ecosystem level: The loss of ecosystem variety and function has the potential to affect the structure as well as the makeup of ecosystems, including the number and distribution of ecosystems, communities, and biomes. It can also have an impact on ecosystem adaptation and resistance to shocks and changes which include fire, severe drought, flood, and epidemic. The recognition and preservation of representative or particular environmental systems, the upkeep and rehabilitation of ecosystem operations and processes such as the cycling of nutrients, sequestration of carbon, and water regulation, and the incorporation of ecologically-based methods into the development strategy and decision-making are all required for the preservation and management of the diversity of ecosystems12.

To illustrate these impacts and implications more clearly, some charts that show some examples,

How different threats affect biodiversity at different levels (graph 1), 

Diversification refers to the diversity and complexity of life on Earth, including anything from genetics to biological systems that exist naturally. It is necessary for biological populations to function correctly and for environmental services to maintain human welfare. Diversification, on the other hand, is endangered by a number of factors, including the destruction of habitat, rising temperatures, invading species, overfishing, and environmental harm. These dangers affect diversity at many different levels, including individuals, communities, populations, ecological frameworks, and biological zones.

how biodiversity loss affects ecosystem services at different levels (graph 2), 

Environmental services are the various, life-sustaining advantages that flourishing ecosystems provide to humanity. Services related to provisioning (such as water, food, wood, and medical treatment), regulating services (e.g. as regulating the climate, prevention of floods, purifying water, or pollination), cultural amenities (such as socializing, learning, religious beliefs, and aesthetically pleasing enjoyment), as well as sustaining services (such as the creation of soil, nutrient cycling, and elementary production) are examples of these1.

and how conservation actions can address biodiversity loss at different levels (Table 3).

The reduction in numbers and the extinction of animal species, communities, groups, ecological systems, and ecological zones as a result of different difficulties such as habitat destruction, warming temperatures, exotic species, excessive harvesting, and pollution are referred to as losses in biodiversity. The diversity of life is required for ecological systems to function effectively properly and to provide ecosystem services that benefit human well-being. As a result, protecting ecological diversity is a critical and pressing issue for humanity.

Conservation activities are reactions aimed at preserving, restoring, and sustaining biodiversity and ecological services. Conservation work can be carried out at several levels, including regional, nationwide, and global. Conservation efforts may additionally concentrate on specific components of the environment, which include species, groups of people, individuals and ecosystems, and biomes.

To figure out the manner in which various conservation campaigns might address decreasing biodiversity. Some of the cases are included in the table.

LEVEL	CONSERVATION ACTION	EXAMPLES
SPECIES	- Protect endangered or threatened species from poaching, hunting, harvesting, or trade. Restore or create habitats for species recovery or reintroduction. Control or eradicate invasive species that compete with or harm native species. Support captive breeding or seed banks for ex-situ conservation of rare or extinct species. Promote genetic diversity and adaptive potential of species.	- The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) regulates the trade of over 35,000 species to prevent their overexploitation 1. The Giant Panda National Park in China covers 27,000 square kilometers of habitat for the endangered giant panda and other wildlife  2. The Galapagos National Park Service eradicated over 250,000 invasive goats from several islands to protect the native flora and fauna.  3. The Frozen Ark project collects and preserves the genetic material of endangered animals for future research and conservation  4. The Millennium Seed Bank Partnership stores over 2.4 billion seeds from over 39,000 plant species for conservation and restoration
POPULATION	- Monitor and assess the status and trends of population abundance, distribution, structure, and viability. - Manage population size and density to prevent overexploitation or underutilization. -Maintain or enhance population connectivity and dispersal to reduce fragmentation or isolation.  Reduce or mitigate human-wildlife conflict by promoting coexistence and compensation schemes.  Implement adaptive management strategies to cope with environmental changes and uncertainties.	- The Living Planet Index (LPI) tracks the population trends of over 21,000 vertebrate species across the globe  - The Marine Stewardship Council (MSC) certifies sustainable fisheries that adhere to the principles of optimal population size, minimal environmental impact, and effective management.  The Yellowstone to Yukon Conservation Initiative (Y2Y) aims to create a network of protected areas and wildlife corridors across 3,200 kilometers of mountain ecosystems in North America. The Human-Wildlife Conflict Collaboration (HWCC) helps communities and conservationists to address the root causes of conflict and develop collaborative solutions. The Adaptive Harvest Management (AHM) program uses mathematical models and monitoring data to adjust the annual regulations for waterfowl hunting in North America.
ECOSYSTEM	Establish and manage protected areas, conservation areas, or other effective area-based conservation measures to safeguard ecosystems and their services. Implement ecosystem-based approaches to integrate the conservation and sustainable use of biodiversity in various sectors, such as agriculture, forestry, fisheries, or tourism.  Restore or rehabilitate degraded ecosystems or landscapes to enhance their productivity, functioning, and services.  Assess and value the economic, social, and cultural benefits of ecosystem services for human well-being and development.  Promote payments for ecosystem services (PES) schemes to provide incentives for conservation and sustainable use of ecosystems.	- The Aichi Biodiversity Targets aim to protect at least 17% of terrestrial and inland water areas and 10% of coastal and marine areas by 2020 .  The Ecosystem Approach is a strategy for the integrated management of land, water, and living resources that promotes conservation and sustainable use in an equitable way .  The Bonn Challenge is a global effort to bring 150 million hectares of degraded and deforested land into restoration by 2020 and 350 million hectares by 2030.  The Economics of Ecosystems and Biodiversity (TEEB) initiative provides a framework for measuring and accounting for the value of nature.  The Reducing Emissions from Deforestation and Forest Degradation (REDD+) mechanism provides financial rewards to developing countries for reducing greenhouse gas emissions from forests .
BIOME	Identify and conserve representative samples of different biomes or ecoregions to capture their diversity and uniqueness.  Maintain or enhance the extent, diversity, and vulnerability of biomes in response to global or regional drivers, such as climate change, land use change, or pollution.  Support transboundary or regional cooperation and coordination for the conservation and management of shared biomes or ecoregions.  Develop and implement biome-specific

Table 2: Conservation actions at the local level

CONSERVATION ACTION	OBJECTIVE	IMPACTS ON DIVERSITY AND ECOSYSTEM SERVICES	REFERENCES
Nature preserves	To protect natural habitats and wildlife from human disturbance and exploitation	To maintain or increase the diversity and abundance of species and populations within the protected area; to preserve or enhance the ecosystem functions and services provided by the protected area; to provide opportunities	10 Ways to Protect and Conserve Biodiversity | Greentumble
Habitat restoration	To restore degraded or destroyed habitats to their original or desired condition	To recover or improve the diversity and abundance of species and populations within the restored habitat; to restore or enhance the ecosystem functions and services provided by the restored habitat; to provide benefits for human well-being such as food security, livelihoods, climate regulation, and disaster risk reduction	The Biodiversity Action Guide
Captive breeding and seed banks	To conserve endangered or threatened species by breeding them in captivity or storing their seeds in secure facilities	To prevent or reduce the extinction risk of species and populations; to maintain or increase their genetic diversity and adaptive potential; to facilitate their reintroduction or reinforcement in the wild; to provide sources of food, medicine, or other biological resources for humans

Table 2: Conservation actions at the regional level

Conservation action	Objective	Impact on biodiversity and ecosystem services	Reference
Reducing invasive species	To prevent or control the introduction and spread of non-native species that threaten native biodiversity and ecosystems	To reduce or eliminate the negative impacts of invasive species on native species and populations; to protect or restore the ecosystem functions and services affected by invasive species; to prevent or reduce the economic and social costs of invasive species for humans	1
Research and monitoring	To collect and analyze data on the status and trends of biodiversity and ecosystem services at regional scales	To improve the knowledge and understanding of biodiversity and ecosystem services; to identify the drivers, pressures, impacts, and responses related to biodiversity loss; to inform and evaluate conservation actions; to raise awareness and communicate findings to stakeholders and decision-makers	1
Regional cooperation	To coordinate conservation actions among countries or regions that share common biodiversity features or challenges	To harmonise policies, laws, standards, and practices related to biodiversity conservation; to facilitate the exchange of information, resources, expertise, and experiences among countries or regions; to address transboundary issues such as wildlife trade, migration, pollution, or climate change; to enhance regional integration and cooperation for sustainable development	2

Table 3: Conservation actions at the global level

Conservation action	Objective	Impact on biodiversity and ecosystem services
Reducing climate change	To limit the increase in global average temperature to well below 2°C above pre-industrial levels by reducing greenhouse gas emissions from human activities	To mitigate the effects of climate change on biodiversity and ecosystem services; to reduce the vulnerability and increase the resilience of species, populations,

• What are the potential solutions and recommendations for reducing or reversing these threats and enhancing the protection and restoration of biological diversity?

• Increasing the extent and effectiveness of protected areas: Protected areas are the places that have been declared and maintained to conserve biodiversity and ecological functions. They can aid in mitigating the destruction and fragmentation of habitat, reducing overexploitation and poaching, controlling species that are invasive and polluting, and mitigating the effects of climate change. However, conservation zones must be expanded to encompass a larger portion of the Earth's surface, particularly in places rich in wildlife or under threat. They must also be controlled and enforced efficiently, with proper financing, manpower, monitoring, and assessment. They also need to blend with the surrounding landscapes and seascapes, as well as include and benefit local people and stakeholders12.

• Promoting sustainable use and management of natural resources: Sustainable natural resource use and management involves utilizing them in a manner that fulfills current requirements without jeopardizing future generations' capacity to satisfy their own. It can assist in balancing the needs of human growth & biodiversity conservation by lowering the strain on natural resources, increasing their efficiency and resilience, and assuring their equal and equitable distribution. Sustainable agriculture, agroforestry, ecological tourism, green energy, the sustainable economy, and remuneration for ecosystem services are all examples of methods that may be implemented12.

• Restoring degraded ecosystems and habitats:

In terms of structure, function, variety, and services, restoring damaged ecosystems and habitats entails restoring them to a particular criterion that is comparable to or superior to their original state. It may contribute to reversing the loss of ecological services and biodiversity by improving species' habitat quality and availability, increasing gene flow and genetic variation across populations, improving ecosystem operations and processes such as the cycling of nutrients, the storage of carbon, and water legislation, and providing benefits to human well-being such as food security, physical well-being, and livelihoods. Approaches such as forest restoration, revegetation, wetlands rehabilitation, coral reef remediation, and aided migration may also be used 12.

• Strengthening the legal and policy frameworks for biodiversity conservation: The laws and regulations that regulate how biodiversity is conserved and exploited at various levels, from local to global, are referred to as policy and legal frameworks for biodiversity conservation. By establishing clear and measurable targets and measurements, establishing guidelines and requirements for optimal practices, enforcement of adherence and accountability systems, allocating assets and duties among participants, promoting collaboration and communication among sectors and stakeholders, and integrating ecological diversity into other policies and plans such as development, trade, health, and education, they can help provide guidance and advantages for biodiversity conservation actions12.

• Enhancing awareness and education on biodiversity issues: The processes of enlightening and teaching people about the vital role of biodiversity for the well-being of individuals and planetary health are referred to as biodiversity awareness and education. They can assist in raising awareness and understanding of the importance of biodiversity and risks among a variety of groups, including decision-makers, experts, investigators, educators, students, media outlets, consumers, and citizens. They can also contribute to the development of mindsets and behaviors that promote efforts to preserve biodiversity by increasing respect and appreciation for nature, promoting interest and curiosity in learning further, encouraging engagement and participation in solutions, and stimulating imaginative thinking and proposals for change12.

These are some of the potential solutions and recommendations for reducing or reversing the threats to biological diversity and enhancing the protection and restoration of biological diversity. 

Discussion::

The review of research reveals that there are numerous and interconnected sources and mechanisms that contribute to threats to the diversity of life due to genetic variation and that those dangers have significant and intricate impacts and repercussions on biodiversity conservation and management at various levels. However, the assessment of the available research reveals substantial inconsistencies and ambiguities in the descriptions, measures, and evaluations of these threats, as well as some trade-offs and disputes between the various aims and techniques for lowering or correcting these threats. As a result, more thorough and interdisciplinary research is required to give a better knowledge of the reasons for and effects of these dangers, as well as to generate more successful and adaptable remedies and suggestions for improving protection and the restoration of biological variety. Potential approaches and suggestions for decreasing or completely reversing these hazards and improving biological diversity protection and restoration include expanding the size and efficiency of protected spaces, promoting responsible utilization and administration of resources from nature, restoring degraded habitats and ecosystems, strengthening policy and legal structures for protecting biodiversity, and raising awareness and education about biodiversity issues.

Conclusion;

The present level of comprehension of the hazards to biological variety posed by genetic variation has been examined in this article. Diversity in biology and variation in genetics are critical for species' survival and adaptation, but they are threatened by a variety of causes that lower their size and variety, disturb their equilibrium and connections, or alter their normal patterns. These challenges have major implications for natural ecological functioning and strength, the supply of services provided by ecosystems, and the general prosperity of individual communities. As a result, it is critical to comprehend the origins and consequences of these dangers in order to devise effective measures to facilitate their avoidance and mitigation. The research paper has added to the body of knowledge by offering a thorough and integrated evaluation of the beginnings, processes effects, repercussions, and treatments as well as recommendations on the subject. The article also made some suggestions for potential study or action on this subject matter, such as improving the estimation and monitoring of ecological diversity and genetic variance changes; determining the acceptable levels, and leaving tips for points of biological products diversity and genetic variations loss or gain; forecasting and modeling biological products variation and genetic variation responses and suggestions to different scenarios; and maintaining and coordinating the process.

Data Availability Statement

The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author.

Author Contribution

LG conceived the idea and designed the study. LG collected the data and conducted the analyses. The author discussed the methods and results and wrote the manuscript.

Conflict of Interest

The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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