How to fight desertification and reverse climate change
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0:01 - 0:05The most massive
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0:05 - 0:10tsunami perfect storm
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0:10 - 0:14is bearing down upon us.
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0:14 - 0:17This perfect storm
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0:17 - 0:22is mounting a grim reality, increasingly grim reality,
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0:22 - 0:27and we are facing that reality
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0:27 - 0:29with the full belief
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0:29 - 0:31that we can solve our problems with technology,
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0:31 - 0:33and that's very understandable.
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0:33 - 0:38Now, this perfect storm that we are facing
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0:38 - 0:41is the result of our rising population,
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0:41 - 0:44rising towards 10 billion people,
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0:44 - 0:47land that is turning to desert,
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0:47 - 0:50and, of course, climate change.
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0:50 - 0:52Now there's no question about it at all:
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0:52 - 0:54we will only solve the problem
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0:54 - 0:58of replacing fossil fuels with technology.
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0:58 - 1:01But fossil fuels, carbon -- coal and gas --
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1:01 - 1:03are by no means the only thing
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1:03 - 1:07that is causing climate change.
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1:07 - 1:09Desertification
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1:09 - 1:14is a fancy word for land that is turning to desert,
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1:14 - 1:17and this happens only when
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1:17 - 1:19we create too much bare ground.
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1:19 - 1:21There's no other cause.
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1:21 - 1:23And I intend to focus
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1:23 - 1:28on most of the world's land that is turning to desert.
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1:28 - 1:33But I have for you a very simple message
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1:33 - 1:37that offers more hope than you can imagine.
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1:37 - 1:39We have environments
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1:39 - 1:42where humidity is guaranteed throughout the year.
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1:42 - 1:45On those, it is almost impossible
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1:45 - 1:48to create vast areas of bare ground.
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1:48 - 1:51No matter what you do, nature covers it up so quickly.
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1:51 - 1:53And we have environments
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1:53 - 1:56where we have months of humidity
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1:56 - 1:57followed by months of dryness,
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1:57 - 2:01and that is where desertification is occurring.
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2:01 - 2:03Fortunately, with space technology now,
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2:03 - 2:05we can look at it from space,
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2:05 - 2:09and when we do, you can see the proportions fairly well.
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2:09 - 2:11Generally, what you see in green
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2:11 - 2:12is not desertifying,
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2:12 - 2:15and what you see in brown is,
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2:15 - 2:19and these are by far the greatest areas of the Earth.
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2:19 - 2:24About two thirds, I would guess, of the world is desertifying.
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2:24 - 2:27I took this picture in the Tihamah Desert
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2:27 - 2:31while 25 millimeters -- that's an inch of rain -- was falling.
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2:31 - 2:33Think of it in terms of drums of water,
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2:33 - 2:36each containing 200 liters.
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2:36 - 2:41Over 1,000 drums of water fell on every hectare
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2:41 - 2:43of that land that day.
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2:43 - 2:46The next day, the land looked like this.
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2:46 - 2:49Where had that water gone?
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2:49 - 2:51Some of it ran off as flooding,
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2:51 - 2:54but most of the water that soaked into the soil
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2:54 - 2:56simply evaporated out again,
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2:56 - 2:59exactly as it does in your garden
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2:59 - 3:02if you leave the soil uncovered.
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3:02 - 3:05Now, because the fate of water and carbon
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3:05 - 3:09are tied to soil organic matter,
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3:09 - 3:13when we damage soils, you give off carbon.
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3:13 - 3:15Carbon goes back to the atmosphere.
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3:15 - 3:19Now you're told over and over, repeatedly,
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3:19 - 3:22that desertification is only occurring
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3:22 - 3:26in arid and semi-arid areas of the world,
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3:26 - 3:30and that tall grasslands like this one
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3:30 - 3:34in high rainfall are of no consequence.
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3:34 - 3:38But if you do not look at grasslands but look down into them,
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3:38 - 3:41you find that most of the soil in that grassland
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3:41 - 3:45that you've just seen is bare and covered with a crust of algae,
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3:45 - 3:48leading to increased runoff and evaporation.
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3:48 - 3:52That is the cancer of desertification
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3:52 - 3:57that we do not recognize till its terminal form.
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3:57 - 4:02Now we know that desertification is caused by livestock,
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4:02 - 4:05mostly cattle, sheep and goats,
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4:05 - 4:08overgrazing the plants,
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4:08 - 4:12leaving the soil bare and giving off methane.
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4:12 - 4:14Almost everybody knows this,
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4:14 - 4:17from nobel laureates to golf caddies,
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4:17 - 4:20or was taught it, as I was.
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4:20 - 4:23Now, the environments like you see here,
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4:23 - 4:26dusty environments in Africa where I grew up,
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4:26 - 4:29and I loved wildlife,
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4:29 - 4:32and so I grew up hating livestock
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4:32 - 4:34because of the damage they were doing.
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4:34 - 4:38And then my university education as an ecologist
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4:38 - 4:41reinforced my beliefs.
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4:41 - 4:46Well, I have news for you.
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4:46 - 4:49We were once just as certain
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4:49 - 4:52that the world was flat.
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4:52 - 4:56We were wrong then, and we are wrong again.
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4:56 - 4:58And I want to invite you now
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4:58 - 5:04to come along on my journey of reeducation and discovery.
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5:04 - 5:07When I was a young man,
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5:07 - 5:09a young biologist in Africa,
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5:09 - 5:14I was involved in setting aside marvelous areas
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5:14 - 5:16as future national parks.
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5:16 - 5:20Now no sooner — this was in the 1950s —
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5:20 - 5:23and no sooner did we remove the hunting,
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5:23 - 5:26drum-beating people to protect the animals,
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5:26 - 5:28then the land began to deteriorate,
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5:28 - 5:33as you see in this park that we formed.
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5:33 - 5:35Now, no livestock were involved,
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5:35 - 5:39but suspecting that we had too many elephants now,
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5:39 - 5:43I did the research and I proved we had too many,
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5:43 - 5:46and I recommended that we would have to reduce their numbers
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5:46 - 5:50and bring them down to a level that the land could sustain.
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5:50 - 5:54Now, that was a terrible decision for me to have to make,
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5:54 - 5:57and it was political dynamite, frankly.
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5:57 - 6:00So our government formed a team of experts
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6:00 - 6:03to evaluate my research.
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6:03 - 6:05They did. They agreed with me,
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6:05 - 6:07and over the following years,
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6:07 - 6:13we shot 40,000 elephants to try to stop the damage.
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6:13 - 6:17And it got worse, not better.
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6:17 - 6:19Loving elephants as I do,
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6:19 - 6:23that was the saddest and greatest blunder of my life,
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6:23 - 6:26and I will carry that to my grave.
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6:26 - 6:28One good thing did come out of it.
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6:28 - 6:31It made me absolutely determined
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6:31 - 6:37to devote my life to finding solutions.
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6:37 - 6:41When I came to the United States, I got a shock,
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6:41 - 6:43to find national parks like this one
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6:43 - 6:48desertifying as badly as anything in Africa.
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6:48 - 6:50And there'd been no livestock on this land
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6:50 - 6:52for over 70 years.
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6:52 - 6:54And I found that American scientists
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6:54 - 6:57had no explanation for this
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6:57 - 7:00except that it is arid and natural.
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7:00 - 7:04So I then began looking
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7:04 - 7:07at all the research plots I could
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7:07 - 7:10over the whole of the Western United States
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7:10 - 7:12where cattle had been removed
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7:12 - 7:15to prove that it would stop desertification,
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7:15 - 7:16but I found the opposite,
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7:16 - 7:19as we see on this research station,
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7:19 - 7:23where this grassland that was green in 1961,
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7:23 - 7:28by 2002 had changed to that situation.
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7:28 - 7:33And the authors of the position paper on climate change
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7:33 - 7:35from which I obtained these pictures
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7:35 - 7:41attribute this change to "unknown processes."
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7:41 - 7:45Clearly, we have never understood
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7:45 - 7:48what is causing desertification,
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7:48 - 7:51which has destroyed many civilizations
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7:51 - 7:54and now threatens us globally.
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7:54 - 7:56We have never understood it.
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7:56 - 7:58Take one square meter of soil
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7:58 - 8:01and make it bare like this is down here,
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8:01 - 8:04and I promise you, you will find it much colder at dawn
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8:04 - 8:07and much hotter at midday
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8:07 - 8:10than that same piece of ground if it's just covered with litter,
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8:10 - 8:12plant litter.
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8:12 - 8:15You have changed the microclimate.
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8:15 - 8:17Now, by the time you are doing that
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8:17 - 8:23and increasing greatly the percentage of bare ground
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8:23 - 8:27on more than half the world's land,
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8:27 - 8:30you are changing macroclimate.
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8:30 - 8:33But we have just simply not understood
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8:33 - 8:37why was it beginning to happen 10,000 years ago?
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8:37 - 8:39Why has it accelerated lately?
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8:39 - 8:41We had no understanding of that.
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8:41 - 8:45What we had failed to understand
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8:45 - 8:49was that these seasonal humidity environments of the world,
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8:49 - 8:51the soil and the vegetation
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8:51 - 8:57developed with very large numbers of grazing animals,
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8:57 - 9:00and that these grazing animals
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9:00 - 9:05developed with ferocious pack-hunting predators.
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9:05 - 9:09Now, the main defense against pack-hunting predators
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9:09 - 9:11is to get into herds,
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9:11 - 9:15and the larger the herd, the safer the individuals.
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9:15 - 9:20Now, large herds dung and urinate all over their own food,
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9:20 - 9:23and they have to keep moving,
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9:23 - 9:25and it was that movement
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9:25 - 9:28that prevented the overgrazing of plants,
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9:28 - 9:30while the periodic trampling
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9:30 - 9:33ensured good cover of the soil,
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9:33 - 9:36as we see where a herd has passed.
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9:36 - 9:42This picture is a typical seasonal grassland.
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9:42 - 9:45It has just come through four months of rain,
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9:45 - 9:49and it's now going into eight months of dry season.
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9:49 - 9:52And watch the change as it goes into this long dry season.
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9:52 - 9:55Now, all of that grass you see aboveground
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9:55 - 9:59has to decay biologically
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9:59 - 10:03before the next growing season, and if it doesn't,
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10:03 - 10:07the grassland and the soil begin to die.
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10:07 - 10:10Now, if it does not decay biologically,
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10:10 - 10:15it shifts to oxidation, which is a very slow process,
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10:15 - 10:18and this smothers and kills grasses,
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10:18 - 10:21leading to a shift to woody vegetation
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10:21 - 10:25and bare soil, releasing carbon.
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10:25 - 10:30To prevent that, we have traditionally used fire.
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10:30 - 10:35But fire also leaves the soil bare, releasing carbon,
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10:35 - 10:38and worse than that,
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10:38 - 10:41burning one hectare of grassland
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10:41 - 10:44gives off more, and more damaging, pollutants
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10:44 - 10:47than 6,000 cars.
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10:47 - 10:51And we are burning in Africa, every single year,
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10:51 - 10:56more than one billion hectares of grasslands,
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10:56 - 10:59and almost nobody is talking about it.
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10:59 - 11:04We justify the burning, as scientists,
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11:04 - 11:07because it does remove the dead material
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11:07 - 11:10and it allows the plants to grow.
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11:10 - 11:13Now, looking at this grassland of ours that has gone dry,
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11:13 - 11:16what could we do to keep that healthy?
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11:16 - 11:19And bear in mind, I'm talking of most of the world's land now.
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11:19 - 11:23Okay? We cannot reduce animal numbers to rest it more
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11:23 - 11:27without causing desertification and climate change.
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11:27 - 11:30We cannot burn it without causing
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11:30 - 11:32desertification and climate change.
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11:32 - 11:36What are we going to do?
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11:38 - 11:41There is only one option,
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11:41 - 11:44I'll repeat to you, only one option
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11:44 - 11:46left to climatologists and scientists,
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11:46 - 11:49and that is to do the unthinkable,
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11:49 - 11:52and to use livestock,
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11:52 - 11:55bunched and moving,
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11:55 - 11:58as a proxy for former herds and predators,
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11:58 - 12:00and mimic nature.
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12:00 - 12:05There is no other alternative left to mankind.
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12:05 - 12:07So let's do that.
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12:07 - 12:10So on this bit of grassland, we'll do it, but just in the foreground.
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12:10 - 12:14We'll impact it very heavily with cattle to mimic nature,
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12:14 - 12:17and we've done so, and look at that.
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12:17 - 12:20All of that grass is now covering the soil
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12:20 - 12:24as dung, urine and litter or mulch,
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12:24 - 12:27as every one of the gardeners amongst you would understand,
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12:27 - 12:31and that soil is ready to absorb and hold the rain,
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12:31 - 12:37to store carbon, and to break down methane.
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12:37 - 12:39And we did that,
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12:39 - 12:42without using fire to damage the soil,
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12:42 - 12:45and the plants are free to grow.
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12:45 - 12:47When I first realized
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12:47 - 12:49that we had no option as scientists
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12:49 - 12:52but to use much-vilified livestock
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12:52 - 12:57to address climate change and desertification,
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12:57 - 13:00I was faced with a real dilemma.
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13:00 - 13:01How were we to do it?
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13:01 - 13:06We'd had 10,000 years of extremely knowledgeable pastoralists
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13:06 - 13:08bunching and moving their animals,
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13:08 - 13:12but they had created the great manmade deserts of the world.
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13:12 - 13:15Then we'd had 100 years of modern rain science,
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13:15 - 13:19and that had accelerated desertification,
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13:19 - 13:21as we first discovered in Africa
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13:21 - 13:24and then confirmed in the United States,
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13:24 - 13:26and as you see in this picture
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13:26 - 13:29of land managed by the federal government.
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13:29 - 13:31Clearly more was needed
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13:31 - 13:33than bunching and moving the animals,
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13:33 - 13:37and humans, over thousands of years,
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13:37 - 13:41had never been able to deal with nature's complexity.
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13:41 - 13:43But we biologists and ecologists
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13:43 - 13:46had never tackled anything as complex as this.
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13:46 - 13:49So rather than reinvent the wheel,
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13:49 - 13:53I began studying other professions to see if anybody had.
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13:53 - 13:56And I found there were planning techniques
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13:56 - 13:59that I could take and adapt to our biological need,
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13:59 - 14:02and from those I developed what we call
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14:02 - 14:05holistic management and planned grazing,
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14:05 - 14:07a planning process,
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14:07 - 14:11and that does address all of nature's complexity
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14:11 - 14:16and our social, environmental, economic complexity.
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14:16 - 14:19Today, we have young women like this one
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14:19 - 14:21teaching villages in Africa
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14:21 - 14:24how to put their animals together into larger herds,
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14:24 - 14:27plan their grazing to mimic nature,
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14:27 - 14:31and where we have them hold their animals overnight --
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14:31 - 14:33we run them in a predator-friendly manner,
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14:33 - 14:35because we have a lot of lands, and so on --
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14:35 - 14:38and where they do this and hold them overnight
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14:38 - 14:39to prepare the crop fields,
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14:39 - 14:43we are getting very great increases in crop yield as well.
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14:43 - 14:45Let's look at some results.
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14:45 - 14:49This is land close to land that we manage in Zimbabwe.
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14:49 - 14:53It has just come through four months of very good rains
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14:53 - 14:56it got that year, and it's going into the long dry season.
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14:56 - 14:59But as you can see, all of that rain, almost of all it,
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14:59 - 15:02has evaporated from the soil surface.
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15:02 - 15:06Their river is dry despite the rain just having ended,
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15:06 - 15:10and we have 150,000 people
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15:10 - 15:13on almost permanent food aid.
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15:13 - 15:18Now let's go to our land nearby on the same day,
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15:18 - 15:21with the same rainfall, and look at that.
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15:21 - 15:23Our river is flowing and healthy and clean.
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15:23 - 15:26It's fine.
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15:26 - 15:31The production of grass, shrubs, trees, wildlife,
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15:31 - 15:34everything is now more productive,
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15:34 - 15:38and we have virtually no fear of dry years.
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15:38 - 15:44And we did that by increasing the cattle and goats
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15:44 - 15:46400 percent,
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15:46 - 15:49planning the grazing to mimic nature
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15:49 - 15:51and integrate them with all the elephants, buffalo,
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15:51 - 15:55giraffe and other animals that we have.
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15:55 - 16:01But before we began, our land looked like that.
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16:01 - 16:06This site was bare and eroding for over 30 years
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16:06 - 16:09regardless of what rain we got.
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16:09 - 16:12Okay? Watch the marked tree and see the change
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16:12 - 16:16as we use livestock to mimic nature.
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16:16 - 16:17This was another site
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16:17 - 16:20where it had been bare and eroding,
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16:20 - 16:23and at the base of the marked small tree,
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16:23 - 16:27we had lost over 30 centimeters of soil. Okay?
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16:27 - 16:28And again, watch the change
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16:28 - 16:31just using livestock to mimic nature.
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16:31 - 16:33And there are fallen trees in there now,
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16:33 - 16:38because the better land is now attracting elephants, etc.
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16:38 - 16:42This land in Mexico was in terrible condition,
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16:42 - 16:44and I've had to mark the hill
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16:44 - 16:48because the change is so profound.
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16:48 - 16:54(Applause)
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16:56 - 17:01I began helping a family in the Karoo Desert in the 1970s
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17:01 - 17:04turn the desert that you see on the right there
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17:04 - 17:06back to grassland,
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17:06 - 17:09and thankfully, now their grandchildren are on the land
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17:09 - 17:11with hope for the future.
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17:11 - 17:14And look at the amazing change in this one,
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17:14 - 17:16where that gully has completely healed
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17:16 - 17:21using nothing but livestock mimicking nature,
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17:21 - 17:25and once more, we have the third generation of that family
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17:25 - 17:29on that land with their flag still flying.
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17:29 - 17:31The vast grasslands of Patagonia
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17:31 - 17:33are turning to desert as you see here.
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17:33 - 17:36The man in the middle is an Argentinian researcher,
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17:36 - 17:40and he has documented the steady decline of that land
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17:40 - 17:43over the years as they kept reducing sheep numbers.
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17:43 - 17:48They put 25,000 sheep in one flock,
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17:48 - 17:52really mimicking nature now with planned grazing,
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17:52 - 17:56and they have documented a 50-percent increase
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17:56 - 18:00in the production of the land in the first year.
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18:00 - 18:03We now have in the violent Horn of Africa
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18:03 - 18:06pastoralists planning their grazing to mimic nature
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18:06 - 18:10and openly saying it is the only hope they have
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18:10 - 18:13of saving their families and saving their culture.
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18:13 - 18:15Ninety-five percent of that land
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18:15 - 18:19can only feed people from animals.
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18:19 - 18:21I remind you that I am talking about
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18:21 - 18:25most of the world's land here that controls our fate,
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18:25 - 18:28including the most violent region of the world,
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18:28 - 18:31where only animals can feed people
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18:31 - 18:35from about 95 percent of the land.
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18:35 - 18:40What we are doing globally is causing climate change
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18:40 - 18:43as much as, I believe, fossil fuels,
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18:43 - 18:47and maybe more than fossil fuels.
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18:47 - 18:50But worse than that, it is causing hunger, poverty,
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18:50 - 18:53violence, social breakdown and war,
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18:53 - 18:56and as I am talking to you,
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18:56 - 18:59millions of men, women and children
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18:59 - 19:01are suffering and dying.
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19:01 - 19:04And if this continues,
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19:04 - 19:08we are unlikely to be able to stop the climate changing,
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19:08 - 19:13even after we have eliminated the use of fossil fuels.
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19:13 - 19:17I believe I've shown you how we can work with nature
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19:17 - 19:20at very low cost
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19:20 - 19:22to reverse all this.
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19:22 - 19:24We are already doing so
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19:24 - 19:28on about 15 million hectares
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19:28 - 19:31on five continents,
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19:31 - 19:33and people who understand
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19:33 - 19:35far more about carbon than I do
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19:35 - 19:38calculate that, for illustrative purposes,
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19:38 - 19:41if we do what I am showing you here,
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19:41 - 19:45we can take enough carbon out of the atmosphere
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19:45 - 19:48and safely store it in the grassland soils
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19:48 - 19:50for thousands of years,
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19:50 - 19:55and if we just do that on about half the world's grasslands
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19:55 - 19:56that I've shown you,
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19:56 - 20:00we can take us back to pre-industrial levels,
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20:00 - 20:02while feeding people.
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20:02 - 20:04I can think of almost nothing
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20:04 - 20:08that offers more hope for our planet,
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20:08 - 20:10for your children,
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20:10 - 20:13and their children, and all of humanity.
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20:13 - 20:16Thank you.
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20:16 - 20:24(Applause)
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20:24 - 20:29Thank you. (Applause)
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20:38 - 20:39Thank you, Chris.
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20:39 - 20:43Chris Anderson: Thank you. I have,
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20:43 - 20:45and I'm sure everyone here has,
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20:45 - 20:48A) a hundred questions, B) wants to hug you.
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20:48 - 20:50I'm just going to ask you one quick question.
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20:50 - 20:54When you first start this and you bring in a flock of animals,
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20:54 - 20:57it's desert. What do they eat? How does that part work?
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20:57 - 20:58How do you start?
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20:58 - 21:00Allan Savory: Well, we have done this for a long time,
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21:00 - 21:03and the only time we have ever had to provide any feed
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21:03 - 21:05is during mine reclamation,
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21:05 - 21:08where it's 100 percent bare.
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21:08 - 21:12But many years ago, we took the worst land in Zimbabwe,
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21:12 - 21:15where I offered a £5 note
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21:15 - 21:17in a hundred-mile drive
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21:17 - 21:19if somebody could find one grass
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21:19 - 21:21in a hundred-mile drive,
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21:21 - 21:24and on that, we trebled the stocking rate,
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21:24 - 21:28the number of animals, in the first year with no feeding,
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21:28 - 21:30just by the movement, mimicking nature,
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21:30 - 21:35and using a sigmoid curve, that principle.
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21:35 - 21:38It's a little bit technical to explain here, but just that.
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21:38 - 21:41CA: Well, I would love to -- I mean, this such an interesting and important idea.
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21:41 - 21:43The best people on our blog are going to come and talk to you
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21:43 - 21:46and try and -- I want to get more on this
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21:46 - 21:49that we could share along with the talk.
AS: Wonderful. -
21:49 - 21:52CA: That is an astonishing talk, truly an astonishing talk,
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21:52 - 21:55and I think you heard that we all are cheering you on your way.
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21:55 - 21:58Thank you so much.
AS: Well, thank you. Thank you. Thank you, Chris. -
21:58 - 21:59(Applause)
- Title:
- How to fight desertification and reverse climate change
- Speaker:
- Allan Savory
- Description:
-
“Desertification is a fancy word for land that is turning to desert,” begins Allan Savory in this quietly powerful talk. And terrifyingly, it's happening to about two-thirds of the world’s grasslands, accelerating climate change and causing traditional grazing societies to descend into social chaos. Savory has devoted his life to stopping it. He now believes -- and his work so far shows -- that a surprising factor can protect grasslands and even reclaim degraded land that was once desert.
- Video Language:
- English
- Team:
closed TED
- Project:
- TEDTalks
- Duration:
- 22:19
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Morton Bast edited English subtitles for How to fight desertification and reverse climate change | |
![]() |
Morton Bast edited English subtitles for How to fight desertification and reverse climate change | |
![]() |
Morton Bast edited English subtitles for How to fight desertification and reverse climate change | |
![]() |
Morton Bast edited English subtitles for How to fight desertification and reverse climate change | |
![]() |
Jenny Zurawell edited English subtitles for How to fight desertification and reverse climate change | |
![]() |
Jenny Zurawell edited English subtitles for How to fight desertification and reverse climate change | |
![]() |
Morton Bast edited English subtitles for How to fight desertification and reverse climate change | |
![]() |
Morton Bast edited English subtitles for How to fight desertification and reverse climate change |