Greenhouse Gases have been of serious global concern to environmentalists. Enteric ruminal fermentation and manure are seen to be responsible for global warming. Based on a better understanding of positive tan-nin effects on ruminant nutrition, the feeding value of browse trees and shrubs containing tannin, their roles on methanogen rumen microbes in overcoming the production of enteric fermentation Gases and the methods of efficient manure handling are presented in this review.

Global warming, droughts and the drowning of the island nations are among the most devastating effects of climate change caused by Greenhouse gas emissions. Therefore, with the goal of reducing Greenhouse gas emissions associated with livestock activities and to create a framework for supporting research projects in animal science, this study was conducted. Through the search and collecting the available information on the Internet, libraries and specialized sites, as well as the holding of various meetings and participation in international expert conferences and the setting up of special questionnaire, research strategies were presented as large-scale projects and research projects. In order to reduce Greenhouse Gases with the origin of animal production and create a complete research chain in Iran, eight research strategies, including studies on livestock species and their number in country, improvement and breeding of ruminant animals, nutritional strategies and increasing the nutritional value of livestock and poultry feeds, improving ruminal microorganisms, research into livestock buildings and facilities, modification of the structure of slaughterhouses, changing and modifying the pattern of fuel consumption and production of biogas, as well as changes and modifying the pattern of animal protein consumption, in the form of 59 master plans and projects were presented. In general, the implementation of national and international commitments, the presentation and implementation of research strategies to create a complete research chain, research control on animal science projects and public education (people and industrial factory farms) are among the most important strategies.

In the past few decades, an increase in Greenhouse Gases has caused global climate imbalance on the Earth which is referred to as "climate change". Studies have shown that this phenomenon has direct and indirect impacts on the natural, economic and social systems. Given the importance and necessity of the phenomenon, “ Urmia Lake Basin” was selected to study the impacts of climate change on climatic parameters. The large-scale outputs of HadCM3 general circulation models were downscaled using multi-linear SDSM model under the emission scenarios of A2 and B2 for the period of 2050s. Based on the results, the daily precipitation has different fluctuations in the coming period. Using HadCM3 model in the basin showed that the amount of precipitation in the period of 2050s will decrease 0. 1 mm under the A2 scenario while will increase 0. 03 mm under the B2 scenario. Precipitation will show reduction in winter and spring while will increase in summer and autumn under the both emission scenarios. The results revealed that average temperature will increase 1. 2 and 1. 1 ° C under A2 and B2 scenarios, respectively; Also, the highest increase in temperature will be up to 1. 5 ° C in winter under A2 scenario and 1. 4 ° C in summer under B2 scenario. The findings of this study can be used to estimate the changes induced in groundwater and surface water resources of the basin, changes in the yield of crops and ranglelands and the occurrence of climate extremes such as droughts and floods in the future.

This research presents a mathematical model for the optimal allocation of oil and gas to different sectors in Iran using operations research techniques. Sectors are residential, commercial, transportation, industries, agriculture, exports, injection to oil reservoirs and power plants as a secondary energy producer. Optimal allocation of energy resources to end-users from 2011 to 2021 has been done using a linear programming model aiming to reduce Greenhouse Gases. Actual data of Iran from 1967 to 2008 are used to forecast the energy demand of different sectors and to illustrate capability of the approach in this regard. The results provide scientific basic for the optimal allocation of energy resources in Iran.

The response of climate to perturbations in GHGs is location dependent. Six experiments: control (CTRL); double CH4; double CO2; double N2O; halved CFC11 and halved CFC12 were carried out to reveal the local area response to different GHGs levels in the atmosphere over West Africa. Double CH4, CO2 and N2O generally induce wetness but they also induce localized dryness at the hilly and mountainous areas of SW Ghana, Central Nigeria, Northern Cameroon and South-eastern Central African Republic. Increase in ground temperature is induced by double GHGs with intensified warming at the north by double CO2. However, patches of cooling are induced at the north. Changes in specific humidity induced by double CO2, CH4 and N2O are similar. Intensified tropical easterly jet is induced by double GHGs. A dipole anomaly of wind with positive at the lower latitude and negative at higher latitude is induced at the northern part of West Africa. Significant reduction in cloud water content is induced from 900 to 400 hPa and 0 and 15oN.

2An increase in the emission of Greenhouse Gases such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) from the soil surface to the atmosphere has been of worldwide concern over the last several decades. Carbon dioxide is recognized as a significant contributor to global warming and climatic change, accounting for 60% of total Greenhouse effect. The aim of this research was to determinate the emission of Greenhouse Gases from different land under agricultural uses. Four types of agricultural land farm, including wheat field, canola field, citrus garden and fallow land were selected to investigate the fate of CO2 in these fields. Gas chromatography technique and close chamber method were used to analyze soil gas samples. Total carbon losses from soil in form of Greenhouse Gases was 4.47, 3.72, 3.38 and 1.89 Mg C ha-1 yr-1 for wheat field, canola field, citrus garden and fallow land, respectively. Total additional carbon to soil from biomass for wheat field and canola field was 4.1 and 4.6 Mg C ha-1 yr-1, respectively. ECB (ecosystem carbon budget) = ∑ C input - ∑ C output. For wheat field and canola field ECB was -0.37 and +0.88, respectively. This indicated that in wheat field carbon was lost and in canola field carbon was sequestrated. Under citrus garden due to changes in soil organic carbon form previous year has showed that carbon was sequestrated.