Emission of Green house gases is the main cause of climate change. Green house gases are carbon dioxide, methane, nitrous oxide, fluorinated gas, etc. These gases are produced primarily through the burning of fossil fuels (oil, natural gas, and coal), solid waste and trees and wood products but also deforestation and soil degradation add carbon dioxide  to the atmosphere and re-growth of forest can be supplemented b y conserving them. Following points describe national parks and conservation area important in Nepal as an effective strategy to reduce green house gas emission:

• Control on deforestation will achieved, which make people to rely on other means of energy such as bio gas for daily activities such as for cooking food, which automatic results reduction in GHG.
• It helps to promote of renewable energy.
• Conservation on biodiversity through national parks help to make environment healthy.
• People can travel, trek, spend time and get enjoyment based on machinery engine will not be used in vast amount and emission of automobiles reduces.
• Concept of national park and conservation area helps to develop concept and awareness about environment protection.

Generally the stability of slope can be enhanced by the different types of corrective measures:

i) Flattering the slope due to which tendency for soil mass to slide is reduced.

ii) Providing a berm below the toe of the slope helps to increase the resistance to the movement of the soil from the slope. It is especially useful when there is a possibility of a base failure.

iii) Drainage helps in reducing the seepage forces and hence increase the stability.

iv) Densification by use of explosives, vibrofloatation,etc. helps in increasing the shear strength of cohesion less soil and thus increasing the stability.

v) Consolidation by surcharging or other methods helps in increasing the stability of slopes.

vi) Grouting and injection of cement or other compounds into specific zones help in increasing the stability of slopes.

vii) Sheet piles and retaining walls can be installed to provide lateral supported and to increase the stability.

viii) Stabilization of the soil helps in increasing the stability of slopes.

ix) Planting the surface of the slope is beneficial to protect the slope against shallow slides.

The design of structure like retaining wall requires the knowledge of the earth pressure acting on the back of the wall because of the soil backfill in contact with it. The amount of the earth pressure against the wall depends on how the wall moves relative to the soil mass.

When there is no wall movement at all i.e., zero movement tendency of wall then corresponding earth pressure is called earth pressure at rest. When the retaining wall has tendency to move outward from the backfill and it gives expansion of soil mass making the soil as loose and makes failure of the soil. In this condition, the failure wedge moves downward. The pressure acting on wall at this failure condition is known as active earth pressure. Since, wall moves away from the backfill earth pressure decreases and approaches to minimum value. When the wall has tendency to move towards the backfill it compress the soil behind the retaining structure and makes the failure of the soil. In this condition, the failure wedge moves upward due to maximum compressive pressure. The pressure at this plastic failure condition is known as passive earth pressure. The pressure at this plastic failure condition is known as passive earth pressure. Since, the wall pushes against the soil mass and thus higher earth pressure is developed.