[MUSIC] Let's talk about Livestock's Long Shadow, its environmental impact on our feeding systems of animals. This comes from the title of a publication by Henning Steinfeld from the Food Agricultural Organization in 2006. And it looked at some of the environmental degradations from livestock systems. Well there are some positives with livestock, they produce a high quality protein in a concentrated form. Animal manure is very important as a source of nutrients, especially carbon, nitrogen, phosphorous, potassium for plant growth. Livestock are also an important sources of income for about 1.3 billion people in the world received their livelihood by livestock production. And livestock contribute to about 40% of the global gross domestic production from agriculture. So they have a very significant positive benefit throughout the world. However, the negatives. Our livestock systems may have negative effects on land, on air, and on water. Eutrophication of water systems from excessive runoff of manure nutrients, especially nitrogen and phosphorus, can cause eutrophication. Green house gas emissions, especially from enteric emissions of methane from herbivores, can create green house gases. And then, nitrous oxide, from manure application of soils, also contributes to greenhouse gases. And then, livestock manure also may contain potential pathogens, bacteria that are harmful. And we know, we've heard of all sorts of food outbreaks from e coli, salmonella, corynebacterium. If we look at what's been happening though, with global livestock production, we can see from 1960, there's been a tremendous increase in the number of poultry, the number of sheep and goats, the number of cattle, the number of pigs. And even the number of rabbits that are grown for meat production and milk production throughout the world. And so, the livestock industry has greatly increased over the last 50 years. And what happens when we feed livestock is, we have our food inputs that go into our animals. And about 10 to 40% of what we feed them is indigestible. That's going to end up in feces. What gets digested is utilized to make products like meat and milk. However, that happens with efficiency of anywhere from 25 to 40%. And so, the inefficient use of absorbed material, absorbed nutrients for producing meat and milk, also ends up in urine, gets excreted as urinary waste, and that also ends up in the environment, or in an animal manure. So if we look at what comprises animal manure, we have feces that are composed of indigestible feed material, endogenous secretions from the gastrointestinal tract, mucus, sloughed cells, enzymes that are secreted. And then we also have bacterial debris. We have bacteria in the large intestine that are excreted with the feces. We have bacteria and ruminants in herbivores that come from the foregut. And secondly, we have urine, that really gets rid of nitrogenous wastes. Things like urea, ammonia, creatinine, and allantoin, allantoin from digestive metabolism of nucleic acids. And also, urine secretes a lot of cations and anions, sodium, potassium, calcium, magnesium, and hydrogen ions, chlorides, phosphates, sulfates, carbonates. And this is to maintain osmotic balance and acid-base balance within the animal. In addition, in manure we have bedding, and also, we have wastewater coming from, maybe, the milking parlor, or cleaning barns and other systems. That manure gets stored, it may go directly on pasture, if animals are grazing. It may be stored in stacks. It may be stored in lagoons and pits. And eventually, it gets out, placed on soils, and we can have losses into the environment. Amonia from urinary excretion into the atmosphere from the barn, from the animals, we also have methane and nitrous oxide. We also have, when the manure goes out to fields, possibilities of nitrates and phosphates in the water systems. When we look at these total animal numbers, how much manure do they produce? So they produce a gross estimate with about 2,630,000 tons annually of animal manure, that'd be dry matter in the world. That contains 43.5 million tons of nitrogen, 19.2 million tons of phosphorus and 37.3 million tons of potassium. So how much land can that manure go on? Well, if we based it on 150 kilograms of nitrogen per hectare, it could go out to almost 290 million hectares of about 1.4 million hectares or billion hectares of arable land. In addition, there's agricultural land, like pastures and areas that are grazed that are about 4.8 billion acres available. And so, we have plenty of land to utilize that nitrogen, the problem is, using it appropriately. In addition, there's about 80 [COUGH] million tons of fertilizer nitrogen that's used each year. Livestock produce a lot of manure. And we have concerns with the impact that manure can have on the environment, both land, air and water.
