Final Exam Study Guide 4-7 PDF

**Final Exam Study Guide: ch 4, 5/6 and 7** **Chapter 4** 1\. How has human population growth changed over the past million years? What factors contribute to this change? What is it about recent times (about 1850 A.D.) that has led to a population explosion? 1. **Agricultural Revolution**: The t...

**Final Exam Study Guide: ch 4, 5/6 and 7** **Chapter 4** 1\. How has human population growth changed over the past million years? What factors contribute to this change? What is it about recent times (about 1850 A.D.) that has led to a population explosion? 1. **Agricultural Revolution**: The transition from hunter-gatherer societies to agricultural societies marked a significant turning point in human population growth. The development of agriculture allowed for more reliable food production, leading to sedentary lifestyles, larger settlements, and increased population densities. 2. **Industrial Revolution**: The Industrial Revolution, which began in the late 18th century, brought about unprecedented technological advancements and economic growth. This period saw a dramatic increase in population due to improved living conditions, sanitation, and healthcare, leading to lower mortality rates and higher life expectancy. - **Lag Growth**: Lag growth refers to a delay or lag between changes in birth rates and changes in death rates within a population. This can occur when improvements in healthcare and living conditions lead to lower mortality rates but birth rates remain high, resulting in a period of rapid population growth. - **Exponential Growth**: Exponential growth occurs when a population increases at a constant rate over a period of time, leading to a doubling of the population size within a fixed interval. This type of growth is characterized by a J-shaped curve on a population growth graph. - **Carrying Capacity**: Carrying capacity is the maximum population size that a given environment can sustain indefinitely, given the available resources and environmental conditions. It represents the balance between the population\'s needs and the capacity of the environment to support those needs. - **Death Phase**: The death phase, also known as the decline phase or population crash, occurs when a population experiences a decline in numbers due to factors such as resource depletion, environmental degradation, or disease outbreaks. This phase follows a period of exponential growth and can lead to a reduction in population size below the carrying capacity of the environment. 2\. How does age distribution affect population growth? Discuss differences between no growth, and rapid growth age structures. Discuss differences in countries that lead to different age structure and how will those differences lead to problems for each in the future. Age distribution profoundly influences population growth by shaping the demographic makeup of a society and impacting factors such as fertility rates, labor force participation, and dependency ratios. The 3 types include no growth (Japan, Germany), slow growth (USA) and rapid growth (India, Congo, other African countries). The 3 types vary in the proportion of pre-reproductive (0-14); reproductive (15-44yrs) and post reproductive (45+ yrs) in each country. A country's financial and infrasture must be adjusted depending on the type of age structure each has. The optimum structure is that of slow growth similar to both the US and Cayman: 1. **Factors Leading to Different Age Structures in Countries**: - **Fertility Rates**: Countries with high fertility rates tend to have younger populations with rapid growth age structures, while those with low fertility rates tend to have older populations with stable or declining age structures. Ex India - **Healthcare and Life Expectancy**: Countries with advanced healthcare systems and higher life expectancies tend to have older populations, as individuals live longer and birth rates decline. Ex Japan - **Economic Development**: Economic development can influence age distribution through factors such as access to education, employment opportunities, and social welfare programs. Developed countries often have older populations due to lower fertility rates and longer life expectancies, while developing countries may have younger populations with higher fertility rates and rapid growth age structures. Leads to **Migration**: Migration patterns can also influence age distribution, as migrants may be predominantly young adults seeking economic opportunities in other countries. This can contribute to rapid growth age structures in both sending and receiving countries. Ex Africa- high numbers of immigrants due to no jobs. a. **Low Birth Rates**: In a slow growth age structure, birth rates are typically below the replacement level, meaning that each generation is not producing enough children to replace themselves. This results in a relatively small cohort of young individuals compared to older age groups. b. **Stable or Aging Population**: The population pyramid of a country with a slow growth age structure tends to be more rectangular or even slightly top-heavy, indicating a larger proportion of adults and elderly individuals compared to children and young adults. This demographic pattern may lead to an overall stable or slowly aging population. c. **High Life Expectancy**: Countries with slow growth age structures often have higher life expectancies due to advances in healthcare, sanitation, and living standards. Longer life expectancies contribute to population aging as individuals live longer, leading to a higher proportion of elderly individuals in the population. d. **Delayed Childbearing and Marriage**: In societies with slow growth age structures, there is often a trend towards delayed childbearing and marriage as individuals prioritize education, career advancement, and personal development. This can contribute to lower fertility rates and a smaller proportion of young children in the population. e. **Urbanization and Migration**: Urbanization and internal migration trends play a role in shaping the slow growth age structure, as younger individuals often migrate to urban centers in search of employment and educational opportunities. This can result in lower fertility rates in urban areas and contribute to population aging in rural regions. f. **Economic Development**: Slow growth age structures are often associated with higher levels of economic development, as countries with advanced economies tend to have lower fertility rates and longer life expectancies. Economic prosperity provides individuals with access to education, healthcare, and family planning services, contributing to smaller family sizes and slower population growth. g. **Challenges of Population Aging**: While slow population growth can mitigate some of the challenges associated with rapid population growth, such as environmental degradation and resource depletion, it also presents its own set of challenges. Population aging can strain healthcare systems, pension programs, and social welfare services, as the proportion of elderly individuals increases relative to the working-age population. 3\. Describe the impact of social factors on population growth. Social factors such as child brides, son preference, sex-selective abortion, lack of access to birth control, sex education, and delayed marriage can significantly influence population growth patterns in various countries. Here\'s how these factors impact India, the USA, Kenya, and Japan: 1. **Child Brides**: - Child marriage, where individuals are married off before reaching adulthood, can lead to higher fertility rates and rapid population growth. Young brides are more likely to have children at a younger age and may have less access to family planning services. - Example: In India, child marriage has been a prevalent practice, particularly in rural areas and among certain communities. Despite legal reforms and government initiatives to combat child marriage, it still persists in some regions, contributing to higher fertility rates and population growth. 2. **Son Preference**: - Son preference refers to the cultural preference for male children over female children, which can lead to higher fertility rates as families continue having children until a male heir is born. - Example: In countries like India and parts of China, son preference has contributed to skewed sex ratios and higher fertility rates. Families may continue to have children until they have a male child, leading to larger family sizes and higher population growth rates. 3. **Sex-Selective Abortion**: - Sex-selective abortion occurs when parents choose to terminate pregnancies based on the sex of the fetus, often preferring male offspring over female. This practice can lead to imbalanced sex ratios and higher fertility rates. - Example: In India and China, sex-selective abortion has contributed to skewed sex ratios, with a higher number of males compared to females in certain regions. This imbalance can lead to social issues and further exacerbate population growth. 4. **Lack of Access to Birth Control and Sex Education**: - Limited access to birth control and comprehensive sex education can lead to higher fertility rates and unintended pregnancies, contributing to population growth. - Example: In Kenya, limited access to contraception and family planning services, particularly in rural areas, can result in higher fertility rates and rapid population growth. Additionally, lack of comprehensive sex education may contribute to misconceptions about contraception and family planning. 5. **Delayed Marriage**: - Delayed marriage, particularly among women, can lead to lower fertility rates and slower population growth as individuals prioritize education, career, and personal development before starting a family. - Example: In Japan, delayed marriage has contributed to declining fertility rates and population growth. Factors such as economic uncertainty, changing social norms, and career aspirations have led many Japanese individuals to postpone marriage and childbearing. 6. **AIDs**. Disease has led to a loss of reproductive age group in Kenya, leaving millions of orphans to be cared for by the government, grandparents and teen girls. The cultural stigma against the use of disease protection and lack of sex education has led to a lower population growth rate over the past 20 years. 4\. Define, give an example and indicate the significance for each of the following: **a. Lag Growth**: Lag growth refers to a delay or lag between changes in birth rates and changes in death rates within a population. This can occur when improvements in healthcare and living conditions lead to lower mortality rates but birth rates remain high, resulting in a period of rapid population growth. Example: human population historically until mid 1800's. Significance: Lag growth is significant because slow growth is more conservative in use of natural resources. b\. **Exponential Growth**: Exponential growth occurs when a population increases at a constant rate over a period of time, leading to a doubling of the population size within a fixed interval. This type of growth is characterized by a J-shaped curve on a population growth graph. Example: humans from 1800s to present. R selected species such as insects. Significance: Exponential growth is significant because it can lead to unsustainable population increases if left unchecked. Understanding exponential growth is crucial for managing populations and resources to ensure long-term sustainability. c\. **J Curve**: The J curve represents the exponential growth of a population on a graph, where population size increases rapidly over time. It is characterized by a curve that resembles the letter \"J,\" with a sharp upward trajectory. Example: The J curve is often used to illustrate population growth in species with abundant resources and low mortality rates. As the population size increases, the rate of growth accelerates, leading to the characteristic J-shaped curve. Significance: The J curve is significant because it visually depicts the concept of exponential growth, highlighting the rapid increase in population size over time. It is a fundamental concept in population ecology and helps researchers understand population dynamics. d\. **Biotic Potential**: Biotic potential refers to the maximum reproductive capacity of a population under ideal environmental conditions. It represents the maximum rate at which a population can grow, considering factors such as birth rate, death rate, and reproductive lifespan. Example: one Russian woman with 69 children in 1700's. Unganan women with 44 children in modern times. Significance: Understanding biotic potential is significant because it helps scientists predict the reproductive capacity of populations and assess their ability to adapt to changing environmental conditions. e\. **Carrying Capacity**: Carrying capacity is the maximum population size that a given environment can sustain indefinitely, given the available resources and environmental conditions. It represents the balance between the population\'s needs and the capacity of the environment to support those needs. Example: A pond ecosystem has a carrying capacity for fish determined by factors such as available food, space, and oxygen levels. Once the fish population reaches the carrying capacity, further growth is limited by resource availability. Significance: Carrying capacity is significant because it influences population dynamics and ecosystem stability. Understanding carrying capacity helps in managing natural resources and mitigating environmental degradation. Unknown for humans f\. **Environmental Resistance**: Environmental resistance refers to factors in the environment that limit population growth and prevent a population from reaching its biotic potential. These factors can include resource scarcity, predation, disease, and competition. Example: In a forest ecosystem, competition for limited resources such as sunlight, water, and nutrients acts as environmental resistance, limiting the growth of plant populations. Significance: Environmental resistance is significant because it helps regulate population sizes and maintain ecosystem balance. It is essential for understanding population dynamics and ecosystem resilience. g\. **Density Dependent Limiting Factors**: Density-dependent limiting factors are environmental factors that influence population growth and become more significant as population density increases. These factors include competition for resources, predation, disease transmission, and territoriality. Example: In a population of deer, as population density increases, competition for food becomes more intense, leading to decreased food availability and lower birth rates. Significance: Density-dependent limiting factors play a crucial role in regulating population sizes and maintaining ecological balance. Understanding these factors is essential for managing wildlife populations and conserving biodiversity. h\. **Density Independent Limiting Factors**: Density-independent limiting factors are environmental factors that influence population growth regardless of population density. These factors include natural disasters, climate events, pollution, and habitat destruction. Example: A severe drought can reduce the availability of water and food resources for a population of birds, leading to decreased reproductive success and population decline, regardless of population density. Significance: Density-independent limiting factors can have significant impacts on population dynamics and ecosystem health, especially in rapidly changing environments. Understanding these factors helps in predicting population responses to environmental disturbances. i\. **Birth Rate**: Birth rate, also known as natality, refers to the number of births per 1,000 individuals in a population within a specific period. It is one of the key factors influencing population growth and demographic trends. Example: A population with a high birth rate, such as a developing country with limited access to contraception and family planning services, may experience rapid population growth. Significance: Birth rate is significant because it directly affects population growth rates and demographic structure. Understanding birth rates helps policymakers and demographers plan for future population trends and resource allocation. j\. **Population Density**: Population density is the number of individuals of a species per unit area or volume of habitat. It is a measure of the concentration of individuals within a population and is influenced by factors such as birth rates, death rates, immigration, and emigration. Example: Cayman has a high population density (75K/ 100 sq miles); Canada has a low population density. Millions of acres for only 30 million. Significance: Population density is significant because it affects resource availability, competition, and interactions within a population. Understanding population density helps in studying species distribution, community ecology, and conservation planning. k\. **Sex Ratio**: Sex ratio refers to the proportion of males to females in a population. It is usually expressed as the number of males per 100 females. Example: India and China each lost 30million females due to sex selective abortion. Significance: skewed ratio leads to sex trafficking and increased rapes as marriageable age women are in short supply **Chapter 5/6** **I. Essay** 1. **Deforestation:** A. Describe at least 5 benefits intact forests provide. Trees provide a multitude of ecosystem services that are essential for the well-being of both ecosystems and human societies. Here are five ecosystem services provided by trees: Trees act as carbon sinks, absorbing carbon dioxide from the atmosphere during photosynthesis and storing carbon in their biomass and soils. This process helps mitigate climate change by reducing the concentration of greenhouse gases in the atmosphere. Additionally, trees play a crucial role in regulating local climates by providing shade, releasing moisture through transpiration, and influencing wind patterns. Trees provide habitats for numerous plant and animal species, thereby supporting biodiversity. Forest ecosystems are home to a wide variety of flora and fauna, from insects and birds to mammals and fungi. The diverse microhabitats within trees, such as tree cavities, bark, and leaf litter, offer shelter, nesting sites, and food sources for many species, contributing to overall ecosystem health and resilience. Tree roots help stabilize soil, reducing erosion caused by wind and water. The litter and organic matter produced by trees contribute to soil fertility by adding nutrients and organic carbon, which support soil microbial communities and promote nutrient cycling. Trees also play a crucial role in preventing nutrient runoff and maintaining water quality by absorbing excess nutrients from the soil. Trees play a vital role in regulating the hydrological cycle by influencing precipitation patterns, reducing runoff, and enhancing groundwater recharge. Forests act as natural sponges, absorbing and storing rainwater, which helps prevent flooding and soil erosion downstream. The intricate root systems of trees also help stabilize stream banks and reduce the risk of sedimentation, improving overall water quality in watersheds. Trees provide aesthetic beauty and cultural significance, enriching landscapes and serving as symbols of identity and heritage for many communities. Green spaces and forests offer opportunities for recreation, relaxation, and outdoor activities, promoting physical and mental well-being. Additionally, trees contribute to the tourism industry by attracting visitors to natural areas, parks, and scenic landscapes, thereby generating economic benefits for local economies. B. list non-food plants that are useful in Cayman. (Name of plant & use). C. What land use is responsible for most forest losses in Africa? D. Discuss agriculture issues in s. America. E. Discuss agriculture issues in Asia: Impacts include palm oil plantations, development and both large and small scale farming leading to multiple problems. F. Discuss land use issues and deforestation in the Cayman Islands: 2. Discuss the difference between Conservation, preservation and development environmental ethics. 3. How are scientists trying to preserve what species remain (discuss the Racing extinction video) 4. *Discuss the history of tree huggers and the development of land preservation as parks.* 5. A. Describe 3 types of diversity -- give examples of each type (species (biological), genetic, ecosystem (ecological). B. Describe at least 5 threats to biodiversity? C.Describe at least 3 reasons why we should we preserve diversity? ***II.Vocabulary: Define/ indicate the significance to environmental science and give an example where possible.*** **ES Chapter 7: Nutrition and Agriculture land problems**\ 1. Discuss the history of agriculture. (include/apply vocabulary terms such as labor intensive, polyculture, etc). 2\. Describe 3 maco- and 3 micro nutrients and their purpose in plants and animals: Macronutrients are chemicals needed in large amounts (nitrogen, phosporus, potassium) to grow crops. Micronutrients are needed in smaller amounts (calcium, iron, copper, etc). GMO's: A. What are GMO's? Give at least 3 examples of plants that have been genetically modified. C. What do you think about this? Would you eat GMO food? Why or why not? 4\. Pesticides. A. Why are pesticides used worldwide? B. What are the problems associated with insecticides? C. Discuss the use of pesticides here in Cayman. 5\. food security: A. What is food security? B. Which countries are food secure and why? 6\. What is Integrated Pest Management? Discuss the benefits and techniques used in IPM. 7\. Soil: II\. Vocabulary: Define, indicate the significance for each and give an example where possible. (60 pts -- 2pt each). Monoculture: Definition: Monoculture refers to the agricultural practice of cultivating a single crop species or variety over a large area of land. Significance: Monoculture simplifies crop management, facilitates mechanization, and maximizes yields of a particular crop. However, it can lead to decreased biodiversity, increased pest and disease susceptibility, and soil degradation over time. Example: Large-scale cultivation of corn or soybeans in industrial agriculture is a common example of monoculture. Polyculture: Definition: Polyculture involves growing multiple crop species or varieties together in the same field or area. Significance: Polyculture promotes biodiversity, enhances ecosystem resilience, improves soil fertility, and reduces reliance on pesticides and fertilizers. It can also provide a diverse and nutritious food supply. Example: Traditional agroforestry systems, such as the \"Three Sisters\" (corn, beans, and squash) cultivated by Indigenous peoples in North America, represent a form of polyculture. Green Revolution: Definition: The Green Revolution refers to a period of rapid agricultural innovation and technological advancement in the mid-20th century, characterized by the development and adoption of high-yielding crop varieties, synthetic fertilizers, and agrochemicals. Significance: The Green Revolution significantly increased global food production, improved crop yields, and alleviated hunger in many parts of the world. However, it also raised concerns about environmental degradation, loss of agrobiodiversity, and social inequities in agricultural development. Example: The introduction of high-yielding rice varieties, such as IR8, in the Philippines during the 1960s is often cited as a successful outcome of the Green Revolution. Kwashiorkor: Definition: Kwashiorkor is a form of severe acute malnutrition characterized by protein deficiency, edema (fluid retention), stunted growth, muscle wasting, and skin lesions. Significance: Kwashiorkor primarily affects children in regions where food insecurity and inadequate dietary protein intake are prevalent. It can lead to serious health complications and even death if left untreated. Example: Kwashiorkor is commonly observed in regions of sub-Saharan Africa, Southeast Asia, and other developing countries experiencing poverty and food shortages. Permaculture: Definition: Permaculture is a holistic approach to sustainable living and land management inspired by natural ecosystems. It emphasizes principles such as observation, diversity, integration, and self-regulation to design resilient and productive human habitats. Significance: Permaculture promotes regenerative agriculture, biodiversity conservation, soil health, water efficiency, and community resilience. It seeks to create productive landscapes that meet human needs while enhancing ecosystem health and diversity. Example: Designing a food forest or perennial garden that mimics natural ecosystems and incorporates diverse plant species, companion planting, and water-harvesting techniques is an application of permaculture principles. Methylmercury: Definition: Methylmercury is a highly toxic organic compound formed when mercury interacts with organic matter in aquatic environments. It accumulates in the food chain, particularly in fish and seafood. Significance: Methylmercury exposure poses serious health risks to humans and wildlife, including neurological damage, developmental disorders, and reproductive impairment. It is a concern in ecosystems impacted by industrial pollution, mining activities, and coal-fired power plants. Example: Consumption of contaminated fish species, such as tuna, swordfish, or shark, can lead to methylmercury poisoning in humans, especially vulnerable populations such as pregnant women and children. Rodenticide: Definition: Rodenticide is a pesticide specifically designed to kill rodents, such as rats and mice, which are considered pests in agricultural, residential, and industrial settings. Significance: Rodenticides are used to control rodent populations and prevent damage to crops, stored food, infrastructure, and public health risks associated with rodent-borne diseases. However, they can also pose risks to non-target species, including wildlife, pets, and humans. Example: Warfarin, bromadiolone, and brodifacoum are common anticoagulant rodenticides used to control rat and mouse populations in agricultural fields, urban areas, and residential properties. Soil Fauna: Definition: Soil fauna refers to the diverse community of organisms living in soil, including earthworms, nematodes, arthropods (e.g., insects, mites), protozoa, bacteria, and fungi. Significance: Soil fauna play critical roles in soil health and ecosystem functioning by decomposing organic matter, cycling nutrients, enhancing soil structure, regulating plant growth, and controlling pest populations. They are indicators of soil fertility and ecosystem vitality. Example: Earthworms are important soil fauna that improve soil structure through burrowing, aerate the soil, and enhance nutrient cycling by breaking down organic matter into nutrient-rich castings. Non-Target Species: Definition: Non-target species are organisms unintended to be affected by a particular pesticide or control measure but may be inadvertently harmed or killed. Significance: Non-target species can include beneficial organisms, such as pollinators, natural enemies (predators, parasitoids), and other wildlife, as well as humans and pets. Accidental exposure to pesticides can disrupt ecosystem balance, reduce biodiversity, and pose risks to non-target species and ecosystems. Example: Insecticides applied to control agricultural pests may inadvertently harm beneficial insects, such as bees, butterflies, and ladybugs, which provide essential ecosystem services such as pollination and biological pest control. Soil Horizons: Definition: Soil horizons are distinct layers or zones in the soil profile that form as a result of soil development processes, including weathering, organic matter accumulation, and mineral translocation. Significance: Soil horizons provide valuable information about soil properties, characteristics, and formation history. They influence soil fertility, texture, structure, drainage, and root growth, affecting plant productivity and ecosystem dynamics. Example: The O horizon, A horizon, B horizon, and C horizon are common soil horizons identified in soil profiles, each exhibiting unique physical, chemical, and biological properties shaped by soil-forming processes. No-Till Farming: Definition: No-till farming, also known as zero tillage or direct seeding, is an agricultural practice that minimizes or eliminates plowing or tillage of the soil before planting crops. Significance: No-till farming helps conserve soil moisture, reduce soil erosion, preserve soil structure and organic matter, and improve soil health and biodiversity. It also reduces fuel consumption, greenhouse gas emissions, and labor costs associated with conventional tillage. Example: Farmers adopting no-till practices cultivate crops directly into untilled soil using specialized planting equipment, such as seed drills or precision planters, without disturbing the soil surface. Frankenfish:   Definition:  Farm raised GMO salmon made by using Eel DNA to enhance the growth rate in salmon.   Significance: the development and approval of genetically modified salmon,referred to as \"frankenfish,\" have sparked debates over environmental risks, food safety, labeling, and ethical considerations. While proponents highlight potential benefits such as enhanced growth rates and increased production e fficiency, critics raise concerns about ecological impacts, consumer choice, and transparency in the food system. The significance of \"frankenfish\" extends beyond its genetic modification, touching on broader issues of sustainability, regulation, and public perception of biotechnology in agriculture and food production.