Ecosystem and Environment 1st Module PDF

Ecology and Ecosystem Level of Organization Ecosytems combine to form a Giant ecosystem Generalized Model of Ecosystem Structure and Function of Ecosystem Ecological Pyramids and Ecological Energetics Individual Efficiency Ecological Efficiency  Ecological Productivity Ener...

Ecology and Ecosystem Level of Organization Ecosytems combine to form a Giant ecosystem Generalized Model of Ecosystem Structure and Function of Ecosystem Ecological Pyramids and Ecological Energetics Individual Efficiency Ecological Efficiency  Ecological Productivity Energy Flow Ecosystem services Biogeochemical cycles (“Bio” - living, “Geo” – earth - rock, “Chemical” - element). The cycling of the nutrients in the biosphere is called biogeochemical or nutrient cycle. It involves movement of nutrient elements through the various components of an ecosystem. There are more than 40 elements required for the various life processes by plants and animals; that it’s proper growth and development. Most important elements are C, H, O, P, K, N, S, Ca, Fe, Mg, B, Zn, Cl, Mo, Co, I & Fe. These elements are continuously cycling in the ecosystem through the biogeochemical cycles and the planet earth has no input of these nutrients. The nutrients (matter) from the dead remains of organisms are recovered and made available to the producers by decomposers. Thus, the nutrients are never lost from the ecosystems. Exchange of nutrients between organisms and their environment is one of the essential aspects of an ecosystem. All organisms require nutrients for their growth, development, maintenance and reproduction. Circulation of nutrients within the ecosystem or biosphere is known as biogeochemical cycles and also called as ‘cycling of materials. There are 3 basic types, 1. Hydrologic or Water cycle, 2. Gaseous cycle (It includes atmospheric Oxygen, Carbon and Nitrogen cycles) and 3. Sedimentary cycle – It includes the cycles of Phosphorus, Sulphur and Calcium - Which are present as sediments of earth. Nitrogen cycle consists of the following steps: fixation, ammonification, nitrification, denitrification and sedimentation. Ecosystem management Ecosystem management is a process that aims to conserve major ecological services and restore natural resources while meeting the socioeconomic, political, and cultural needs of current and future generations. i. adaptive management, ii. natural resource management, iii. strategic management, and iv. command and control management.  Adaptive Management is based on future predictions Natural resource management refers to the management of natural resources such as land, water, soil, plants and animals, with a particular focus on how management affects the quality of life for both present and future generations Strategic management encourages the establishment of goals that will benefit the ecosystem while keeping socioeconomic and politically relevant issues in mind Command and control management utilizes a linear problem-solving approach where a perceived problem is solved through controlling devices such as laws, contracts and/or agreements Fate of environmental pollutants 1. The concentration of Hg in a waterbody is 0.55 mg/L. However, concentration in small fishes were found as 0.8 mg/Kg and in large fish as 1.56 mg/Kg. Calculate the BCF, BAF, BMF. 2. In a locality the soil was found to be contaminate with 0.45mg/Kg of Cd. A number of wild herbs were collected from the locality and average Cd concentration was found to be like this Species A- 0.56 mg/Kg Species B – 0.25 mg/Kg Speies C – 1.22 mg.Kg a. What are their BCFs? Which species are hyperaccumulators? In the same locality 1st level consumer X and Y feeding on A and C respectively were found to contain 2.8 mg/Kg and 2.6 mg/Kg Cd. b. What were their BAF and BMF? What was the average TMF?  ❑ India is both a major greenhouse gas emitter and one of the most vulnerable countries in the world to projected climate change. ❑ The country is already experiencing changes in climate and the impacts of climate change, including water stress, heat waves and drought, severe storms and flooding, and associated negative consequences on health and livelihoods. Prepared By Joint Global Change Research Institute and Battelle Memorial Institute, Pacific Northwest Division ❑ With a 1.3 billion but growing population and dependence on agriculture, India probably will be severely impacted by continuing climate change. Global observations of melting glaciers suggest that climate change is well under way in the region, with glaciers receding at an average rate of 10–15 meters per year. If the rate increases, flooding is likely in river valleys fed by these glaciers, followed by diminished flows, resulting in water scarcity for drinking and irrigation. All models show a trend of general warming in mean annual temperature as well as decreased range of diurnal temperature and enhanced precipitation over the Indian subcontinent. A warming of 0.5o C is likely over all India by the year 2030 (approximately equal to the warming over the 20th century) and a warming of 2-4o C by the end of this century, with the maximum increase over northern India. Increased warming is likely to lead to higher levels of tropospheric ozone pollution and other air pollution in the major cities. Increased precipitation⎯including monsoonal rains⎯is likely to come in the form of fewer rainy days but more days of extreme rainfall events, with increasing amounts of rain in each event, leading to significant flooding. Drizzle-type precipitation that replenishes soil moisture is likely to decrease. The timing may also shift, causing a drying during the late summer growing season. Specific effects Agriculture. High-input, high-output agriculture will be negatively affected even as demands for food and other agricultural products rise because of an increasing population and expectations for an improved standard of living. Water: Glacier melt may yield more runoff in the short term but less in the medium and long terms. More severe storms (especially cyclones) will cause more damage to infrastructure and livelihoods and exacerbate salt water intrusion in storm surges. Changes in the timing and amount of monsoon rains will make the production of food and other agricultural products more uncertain, so that, even in good- weather years, farmers will be more likely to make decisions leading to lower- productivity.  Exacerbation of Inequality: The welfare of those who are affected by climate change and who have limited means to adapt may act as a force that can change governments, strain public budgets, and foster unrest. About one-third of Indians are extremely poor, and 60 percent depend upon agriculture for their livelihoods. Energy: As India searches for additional sources of energy to meet rising demand, climate change mitigation efforts may constrain its use of indigenous and imported coal, oil, and gas, while development of nuclear energy will be slow at best and likely to encounter opposition. Other non-emitting technologies will require technology transfer and capacity-building. Migration: India receives immigrants from a number of countries. Under climate change conditions, it may be flooded with many more, particularly from Bangladesh. Such migration may exacerbate tension between the two countries as well as putting a strain on Indian central and state governments.