The background of the Kyoto protocol, stakes that go beyond
the fight against climatic change…
The context of agricultural development
Is the trend reversible?
Box : Abstracts of Article 3 of the Kyoto protocol
The discussions that took place at the Sixth Session of the Conference of
Parties on the Convention on Climate Change (COP 6), in The Hague, in November
2000, mainly concerned the "limitation" of emission sources of greenhouse
gases and the possible compensations by CO2 sinks located in forest
ecosystems or in agriculture. The priority must of course remain the limitation
of emissions as this is the only sustainable solution, but it is nevertheless
necessary to consider the background of Articles 3.3 and 3.4 of the Kyoto
protocol (see box below).
The mitigating or compensating effect forests and farming have on greenhouse
gases are a tangible and measurable fact. Its main advantage is that the
effect is immediate (if the area is not deforested) and becomes effective
after 3 to 5 years when forests are replanted or when changes occur in
agricultural practices. It thus directly complements the limitation of emissions
which, due to problems linked to its implementation, will only become beneficial
in several decades. The storage effects forecasted can be evaluated for each
recommended practice and range from 0.1 tons of carbon/ha/year (in dry areas)
to several tons (agro-forestry, reforestation, pastures). On an international
scale, the global evaluations are extremely high, i.e. between 1 and 2 billion
tons of carbon/year (Gt or Pg). The latest evaluations showed that this could
entail a 40 to 70 ppm decrease of the CO2 concentration in the
atmosphere over the 21st century. These figures are significant,
but the actual data really depends on the area concerned, which could be
of several billion hectares if there is a political and economic incitement.
One essential feature of this storage is that it is unstable on the long
term (possible reversibility).
It is thus very important to see what exactly are the other advantages
of carbon sequestration in terrestrial ecosystems ("win-win
situation").
Experts (1) consider that these advantages
are so important they deserve to be taken into account individually and not
only in the framework of the Kyoto agreements, with the help of development
organisation financing or EEC agro-environmental subsidies, for example.
However, these agreements foster national and international dynamism and
motivation, which should lead to the implementation of these sustainable
development projects.
[R] The context of agricultural development
It is essential to recall the conditions in which agriculture developed on
an international scale. Whether in the North or the South of our planet,
agriculture has developed at the expense of natural ecosystems (forests,
pastures, etc.), the most important stocks of carbon on Earth (200 to 300
tons of carbon per hectare). Over half of all carbon stocks are in the soil
where they have accumulated over hundreds or even thousands of years. The
soil, with 1500 Gt (more than twice that of vegetation - 650 Gt), represents
the largest carbon stock on Earth.
Over the last century, more than 40% of the carbon contained in soils was
mineralised into CO2 as more and more land was being cultivated.
Thus, until the 1970s, this phenomenon was one of the main anthropogenic
causes of the increase in greenhouse effect gases.
We now know the exact causes, the first being tillage that goes with all
cultivation and that exposes the organic matter, previously protected by
the soil structure, to the action of micro-organisms. Thus tillage, which
has been the symbol of soil fertility and agriculture for the last 2000 years,
is now called into question. As a matter of fact, tillage may really prove
harmful when the following conditions are combined:
- roughly fifty years of continuous cultivation,
- insufficient organic matter restored to the soil to compensate losses.
These two conditions were generally fulfilled during the 20th
century with the development of a more intensive agriculture
internationally: to this effect we can say that, in these conditions, the
system cannot be sustainable and must be modified.
Indeed, a parallel can be drawn a posteriori, between the increase
of cultivated areas at the expense of forests and the loss of carbon and
increased sensitivity of the upper soil layer to deterioration and in particular
to erosion and desertification. The United States was most probably the first
to experience these effects due to increased wind erosion in the 1930s in
the great prairies of the central regions. The USA is also the first to have
modified their cultivation practices by introducing "conservation tillage".
Roughly 2 billion hectares of land are affected by degradation, that is over
30% of all land on Earth. If this trend was to continue, we can wonder, with
good reason, if there will be enough food for the forecasted 9 to 11 million
inhabitants in 2050.
On the other hand, we can also partly associate the deterioration of soils
(erosion and runoff) to the current deterioration of environmental quality
(water pollution due to nitrates and pesticides, floods as more and more
rivers burst their banks, decreasing biodiversity, mono-tonous landscapes,
etc.).
And if so, which solutions can be recommended? The harmful trends observed
today are indeed reversible.
The carbon content of soils and, thus, the quantity of organic matter are
of extreme importance for the mechanic (in particular, the state of
agglomeration), chemical and biological properties of soils. It is the source
of soil biological activity, i.e. of the life of soils and of terrestrial
biodiversity.
The solution would be to partially reconstruct soil carbon stocks through
the conservation or restoration of grasslands and forests, as well as by
modifying farming practices.
Over the last twenty years, CIRAD, a French scientific organisation specialised
in tropical agronomy, has been carrying out experiments in several tropical
countries and in particular in Brazil. These experiments involve "no-till"
methods and permanently covering the soil with living (succession of crops)
or dead (plant matter, mulch) vegetation. A different crop is sowed on the
previous one (direct sowing). This was one of the main themes of an exhibition
on the "Planetary Garden" at La Villette (Paris, France). Experiments should
soon be carried out in five developing countries in the framework of an
agro-biological action plan funded by the French Ministry of Cooperation.
It will be necessary to draw a complete environmental assessment of these
practices.
Similar practices, known as "conservation tillage", have been developed in
the United States, Canada, Australia and Argentina to fight wind and water
erosion. Over 40 million hectares of land are already concerned by these
practices, an area that expands considerably each year. In the United States,
37% of all cultivated land is concerned and this should have doubled by 2020
entailing a considerable increase of the carbon stocks (1 Gt). This explains
the United State's position as regards CO2 sinks (which must of
course not be used as an excuse to restrict CO2 emissions).
FAO would like these practices, known as "conservation farming", to be extended
to the whole Southern Hemisphere. Only Europe, with less than 1 million hectares,
is not concerned by these evolutions, although such extensive practices could
be a sustainable solution to combat soil deterioration and pollution.
There are solutions for carbon stocks, through restoration of deteriorated
grasslands or pastures, in particular in dry areas (over 2 million hectares).
Increasing the amount of grasslands would allow livestock to have a more
natural diet, an essential problem in today's Europe.
Needless to say, tropical forests must be preserved. 17 million hectares
are cleared each year and this represents an important source of
CO2 emission and a great loss of biodiversity. The development
of agro-forestry (alternating trees, grasslands and crops) is a way to put
an end to deforestation by promoting economic development.
All these stakes are essential at an international level and are not sufficiently
put forward during discussions on climatic change; in particular the fact
that the three Conventions on Climate, Desertification and Biodiversity can
be associated by simply acting on the carbon stocks in forests but also in
grasslands and in the soil in general.
It is thus a unique opportunity to ensure the sustainability of our development.
Limiting emissions must of course remain the first priority, but this justifies
the fact that the accent is also put on these opportunities in Articles 3.3
and 3.4 of the Kyoto protocol applied to forests and farming practices on
an international scale (that is to say applied to developing countries).
This article is taken from the "Courrier de l'environnement
de l'INRA, n°41", by Michel Robert.
Translated from French by Nicole Scott.
3.3. The net changes in greenhouse gas emissions from sources and removals
by sinks resulting from direct human-induced land use change and forestry
activities, limited to afforestation, reforestation, and deforestation since
1990, measured as verifiable changes in stocks in each commitment period
shall be used to meet the commitments in this Article of each Party included
in Annex I. The greenhouse gas emissions from sources and removals by sinks
associated with those activities shall be reported in a transparent and
verifiable manner and reviewed in accordance with Articles 7 and 8.
3.4. Prior to the first session of the Conference of the Parties serving
as the meeting of the Parties to this Protocol, each Party included in Annex
I shall provide for consideration by the Subsidiary Body for Scientific and
Technological Advice data to establish its level of carbon stocks in 1990
and to enable an estimate to be made of its changes in carbon stocks in
subsequent years. The Conference of the Parties serving as the meeting of
the Parties to this Protocol shall, at its first session or as soon as
practicable thereafter, decide upon modalities, rules and guidelines as to
how and which additional human-induced activities related to changes in
greenhouse gas emissions and removals in the agricultural soil and land use
change and forestry categories, shall be added to, or subtracted from, the
assigned amount for Parties included in Annex I, taking into account
uncertainties, transparency in reporting, verifiability, the methodological
work of the Intergovernmental Panel on Climate Change, the advice provided
by the Subsidiary Body for Scientific and Technological Advice in accordance
with Article 5 and the decisions of the Conference of the Parties. Such a
decision shall apply in the second and subsequent commitment periods. A Party
may choose to apply such a decision on these additional human-induced activities
for its first commitment period, provided that these activities have taken
place since 1990.
[R]
Note
(1) Expertise report: "Soils and carbon sequestration.
Proposals for land management in tropical and arid areas". Michel Robert,
FAO-AGL, Rome 2000, 50 p. (publishing in progress).[VU]
