An ecosystem is a system formed by the interaction of all living organisms with each other and with the physical and chemical factors of the environment in which they live, all linked by transfer of energy and material.

There are many reasons as to why population growth is seen as a threat to the environment. For example, human populations use up natural resources, omit greenhouse gases contributing to climate change, destroy habitats resulting in loss of biodiversity, and increase air and water pollution levels.

• In recent years Dams and multi purpose projects have come under great opposition and scrutiny  for various reasons:
  
• 1. Regulating and damming of rivers affect their natural flow causing excessive sedimentation on the rivers beds resulting in poor habitat for the rivers aquatic life.
  
• 2.Dams also fragment rivers making it difficult for the aquatic fauna to migrate especially for spawning.
  
• 3.The reservoirs that are built on the flood plains also submerge the existing vegetation and soil leading to its decomposition over time.
  

• Eco-tourism is also known as Responsible Tourism. 
  
• It is called as Responsible Tourism because it puts responsibility on the shoulders of tourist to conserve the environment.
• It also make sure tourist and tourism activities does not disturb the local population and their livelihood.
  

• Ecology is the branch of science that deals with the study of interactions between living organisms and their physical environment.
  

• One of the best measure conserve eco-system is vanamahotsav celebration.
• Vanamahatsav is a tree planting festival celebrated annually.
• It is celebrated since 1950.
• Vanamahotsav week celebrated from July 1 - July 7 Every year

• The study of the interactions between living things and their environments is known as ecology.
  
•  In ecology, everything is connected to everything else and there is a constant interaction between organisms and their environment.
  
• Autecology is the study of individual organism or individual species. It is also known as population ecology.
  
• Autecology helps us to understand the relationships between individual plants and environment.
  

• Planktons are passively floating in upper water, nektons are actively swimming while benthos lead sedentary life upon the sea bottom. 
  
• Plankton (singular plankter) are a diverse group of organisms that live in the water column of large bodies of water and that cannot swim against a current.
  
• They provide a crucial source of food to many large aquatic organisms, such as fish and whales.
  

• Ecology is the scientific analysis and study of interactions among organisms and their environment.
  
• It is an interdisciplinary field that includes biology, geography, and Earth science.
  
• Ecology deals with the study of: a) Living beings. b) Living and non-living components. c) Reciprocal relationship between living and non living components.
  
• Ecology is distinguished from natural history, which deals primarily with the descriptive study of organisms.

• Bringing together the local communities and government agencies will help in environmental  reconstruction.
• Management of environmental resources by the Government alone is less efficient
  
• Good Governance concept of Co-operation of Government with Local communities along with civil society organizations will ensure efficient management of environmental resources
•  Also ensures Transparency and accountability in the environmental resources management

Climate is the long-term average of weather, typically averaged over a period of 30 years. Some of the meteorological variables that are commonly measured are temperature, humidity, atmospheric pressure, wind, and precipitation.