24 Slices
Medium 9781780644325

16 Thermodynamic and Kinetic Control of Methane Emissions from Ruminants

Malik, P.K CABI PDF

16

Thermodynamic and Kinetic

Control of Methane Emissions from Ruminants

Richard A. Kohn*

University of Maryland, College Park, USA

Abstract

CH4 emissions occur directly from animal digestion (enteric) and from animal waste that is stored under anaerobic conditions. In both regards, CH4 emissions depends on kinetic and thermodynamic factors. With kinetic control, the profile of products formed depends on the relative rates of the different competing reactions. In turn, the rates of reactions depend on substrate concentrations and enzyme activities, and these enzyme activities depend on microbial growth or enzyme synthesis. With thermodynamic control, which pathway branches are available and the direction of metabolite flow depends on the concentrations of reactants and products. Biologists have focused on controlling the kinetic elements of fermentation such as enzyme function, microbial activity, gene expression or provision of substrates. However, fermentation is often controlled by thermodynamics.

See All Chapters
Medium 9781780644325

4 Nitrogen Emissions from Animal Agricultural Systems and Strategies to Protect the Environment

Malik, P.K CABI PDF

4

Nitrogen Emissions from Animal

Agricultural Systems and

Strategies to Protect the

Environment

Richard A. Kohn*

University of Maryland, College Park, USA

Abstract

Animal production systems are among the largest contributors of reactive nitrogen to the environment. Nitrogen (N) is lost from animal agriculture through volatilization to the atmosphere (NH3, N2O, NO) and runoff and leaching to water resources (NH4+,

NO3–, organic N). Most N losses from agriculture are in a form (NH4+, NH3, NO3–) that does not directly affect climate change.

However, these compounds have serious environmental consequences of their own, including contributing to haze, acidity of rain, eutrophication of surface water bodies and damage to forests. In addition, a significant amount of nitrous oxide (N2O) emissions result from animal agriculture because the ammonium and nitrates from agriculture are converted to N2O during manure storage and crop production. N2O is a potent greenhouse gas. Although animals emit very little nitrogen directly to the air, animal excreta (urine and faeces) contains environmentally reactive nitrogen, which begins moving to the air and water from the moment it leaves the animal, unless it is incorporated into a crop or converted to molecular nitrogen (N2). Nitrogen is lost from the barn floor or pen, storage facility and from cropland during manure application and crop growth. Additional nitrogen is lost to the environment when

See All Chapters
Medium 9781780644325

22 Feed-based Approaches in Enteric Methane Amelioration

Malik, P.K CABI PDF

22

Feed-based Approaches in

Enteric Methane Amelioration

P.K. Malik,* R. Bhatta, N.M. Soren, V. Sejian, A.

Mech, K.S. Prasad and C.S. Prasad

National Institute of Animal Nutrition and Physiology, Bangalore,

India

Abstract

22.1 Introduction

Mitigation of methane (CH4) emissions from ruminants is necessary not only from the global warming point of view but also for saving dietary energy. Livestock being the significant contributors to the anthropogenic

CH4 pool have remained the prime target of global research for the past two decades, in order to find suitable, sustainable and economical possibilities of reducing enteric

CH4 emission. The adoption of a particular strategy by the stakeholders depends on the input cost, economic status, toxicity to host/ inhabiting microbes, mitigation potential and persistency in long run. Among all the available options, feed-based intervention seems remarkable, and can be tried anywhere by making little alterations to the available feed resources and prevailing feeding practices. This chapter deliberates the pros and cons of various nutritional interventions, along with their future prospects to reduce enteric CH4 emission. Issues like necessity of methanogenesis in the rumen, the feasibility of reducing livestock numbers and cutting down emissions, and the expected reimbursements that arise from this practically feasible reduction, are well debated in the chapter.

See All Chapters
Medium 9781780644325

10 Carbon Sequestration and Animal-Agriculture: Relevance and Strategies to Cope with Climate Change

Malik, P.K CABI PDF

10

Carbon Sequestration and

Animal-Agriculture: Relevance and Strategies to Cope with

Climate Change

C. Devendra*

Consulting Tropical Animal Production Systems Specialist,

Kuala Lumpur, Malaysia

Abstract

Carbon sequestration is an important pathway to stabilize the environment with minimum effects of climate change. Farming systems provide a non-compensated service to society by removing atmospheric carbon generated from fossil fuel combustion, feed production, land restoration, deforestation, biomass burning and drainage of wetlands.

The resultant increase in the global emissions of carbon is calculated at 270 Gt, and increasing at the rate of 4 billion tonnes year–1. Strategies to maximize carbon sequestration through enhanced farming practices, particularly in crop–animal systems, are thus an important priority to reduce global warming. These pathways also respond to agricultural productivity in the multifaceted, less favoured rainfed environments. Sustainable animal-agriculture requires an understanding of crop–animal interactions and integrated natural resource management (NRM), demonstrated in the development of underestimated silvopastoral systems (tree crops and ruminants).

See All Chapters
Medium 9781780644325

24 Summary

Malik, P.K CABI PDF

24

Summary

P.K. Malik,* R. Bhatta, M. Saravanan and L.

Baruah

National Institute of Animal Nutrition and Physiology, Bangalore,

India

Abstract

This chapter summarizes the full content of this book where contributors have addressed various aspects of livestock production visà-vis climate change. Improving livestock production and productivity is the need of the hour to accomplish the ever increasing demand of the populace. Climate change appears to be a major constraint in this endeavour as it severely affects livestock directly or indirectly. Further, livestock itself is accountable for the climatic variations and negative environmental complications of climate change by dispensing large quantities of greenhouse gases into the atmosphere.

The implications of climate change on livestock, the involvement of livestock in climate change, mitigation approaches and adaptation strategies for minimizing the adverse impact and reducing enteric methane (CH4) emissions debated in the various chapters of this book are summarized here.

See All Chapters

See All Slices