List of messages of the Land

Message / Invitation to the online discussion
Message 1: from Deborah Bossio, Thursday 24/3/2005
Message 2: from Will Critchley, Thursday 24/03/2005
Message 3: from Richard J. Thomas, Thursday 24/03/2005
Message 4- from Felix Kolawole Salako, Thursday 24/3/05
Message 5- from christian valentin –Friday 25/3/05
Message 6- from Hanspeter Liniger – Friday 25/3/05
Message 7- from Dr Salako- Friday 25/3/05
Message 8- from Don Peden from ILRI on Friday 25/3/05
Message 9 -from dr.Ghulam Murtaza- Saturday 26/03/05
Message 10 from from Hans Liniger -a complement to message 6 send on Friday 25th
Message 11 from Bancy Mati- Saturday 26/3/05
Message 12 &13 - Prof Joshi S.G. – Sunday 27/03/05 & Monday 28/03/05
message 14 – from Guy Evers – Monday 28/3/05
Message 15- from James Chiphampa from Malawi- Tuesday 29/3/05
Message 16- from Godert Van Lynden of ISRIC – Tuesday 29/3/05
Message 17- From Kenneth Cassmann, Tuesday 29/3/05
Message 18-from Patricia Kabatazi-Wednesday 30/3/05
Message 19-from Patricia Kabatazi- Wednesday 30/3/05
Message 20 –from Deborah Bossio - summary of first week– Thursday 31/3/05
Message 21-from Godert Van Lynden from ISRIC- Thursday 31/3/05
Message 22 – message from james Chimpamba- Thursday 31/3/05
Message 23-message from Sarah Scherr- Thursday 31/3/05
Message 24-from L. Thiombiano from FAO – Thursday 31/3/05
Message 25-from Peter Hobbs – Thursday 31/3/05
Message 26 : from Kolawole Saloko- Friday 1/4/05
Message 27 – from kolawole Salako – Friday 1/4/05
Message 28- from Freddy Nachtergaele in FAO-soil service- Friday 1/4/05
Message 29- from Kolawole Salako- Friday 1/4/05
Message 30- from Sjef Kauffman and Godert Van Lynden- Monday 5/4/05
Message 31: from Patrizia Kabatabazi- Monday 5/4/05
Message 32: from Deborah Bossio –Tuesday 6/4/05

Invitation to the online discussion
Dear All,

Thank you for your interest in the Comprehensive Assessment of Water Management in Agriculture (the CA). The assessment (www.iwmi.cgiar.org/assessment) brings together people with knowledge and experience to critically evaluate issues of water, food, livelihoods, and environment. The purpose of the CA is to look at trends, conditions and response options across a range of themes to provide policy relevant guidance to investments and management decisions for water management in agriculture.

We would like to invite you to participate in the first round of email discussions in relation to the Land Degradation Chapter of the CA. In this chapter we will focus on critical issues in land degradation that are essential to bring into water, food and environment discussions and decision making.

In this first discussion we would like to develop a concrete (small) set of widely agreed upon key messages that will form the basis of the chapter. For this discussion, please suggest, briefly, what you see as the most important points to make in this chapter. A wide range of input is desired at this time, which will later be summarized for further refinement and synthesis.

Please address the following two questions:

1) What are the most important (and underappreciated?) trends and underlying processes with respect to land degradation and water management for agriculture?

2) What are the most promising options available to address negative trends in land degradation, and thereby conserve and improve the management of water?

This email discussion will begin now and continue to the end of March, at which time the chapter writing team will be formed and the process of preparing the detailed paragraph-by-paragraph outline will take place. An additional discussion will take place related to the proposed outline, before final drafting of the chapter. A chapter workshop with the writing team is proposed for early June to discuss and finalize the paragraph outline.

We have a large and diverse set of chapter participants invited to this discussion. Please introduce yourself and your background to the group with your first posting.

This is a moderated discussion. The moderator receives all the messages and redistributes them. The discussion contributions and support documents will all be available on the following website: http://www.iwmi.cgiar.org/assessment/index.asp?id=1407

We look forward to hearing from you.

Best regards,
Deborah Bossio

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Message 1: from Deborah Bossio, Thursday 24/3/2005
Dear online Discussion Participants,

My name is Deborah Bossio, and I am the Coordinating Lead Author of the Land Degradation Chapter. My background is in Soil Science, and I work for IWMI.

To start off the discussion I submit to you a few key messages that have already been suggested. This is not intended as complete list of important topics, and you may not agree with them. Please make your own suggestions, and/or comment on these.

Trends and Processes

• Declining soil organic matter is related to, and probably exceeds in extent, all other degradation processes and has significant impacts on productivity, resilience of agroecosystems, local and regional water cycles, and global C cycles.

• Soil erosion and sedimentation are a major cause of failure for investments in water infrastructure, limiting on site productivity, reducing useful life of storage facilities, and increasing costs of infrastructure maintenance.

• One-way nutrient flows in regional and global food trade are a significant driving force of nutrient depletion and water pollution.

• Land degradation is inadequately monitored which is impeding implementation of national and international development goals.

Response Options

• Rehabilitation of degraded soils is a key entry point for increasing the productivity of water in agriculture.

• Intensification of smallholder farming systems through reversal of land degradation is already contributing to increased food security and providing other ecosystem benefits in many localized “bright spots”; further investments in this sector are an important response option.

• Appreciation of the full range of ecosystem service benefits that are achieved from investments in rehabilitation of degraded lands can unite agriculture, water and environment sectors to increase the base for necessary investments.

• Landscape level approaches that take into account multiple stakeholders, and connectivity of landscape components, are necessary to sustain productivity, livelihood options and resilience of agro-ecosystems.

Thank you for your contributions,

Best regards,
Deborah

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Message 2: from Will Will Critchley, Thursday 24/03/2005
Will Critchley from Holland, Lead author of the CA-Land Degradation chapter, is adding few additional points to the previous message of Deborah Bossio.

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Dear participants,


Here goes with a few additional points.

Under Trends and Processes:
1. People and demographics have a huge and not easily predictable impact on LD. Must be understood and are crucial in any 'remedy'
2. Insecurity of land tenure often leads to land degradation
3. Energy needs of the rural population - if not met from outside - lead to consumption of biomass and reduction in SOM and fertility

Under Response Options:
1. LD should not/ cannot be isolated from broader rural development packages/ programmes
2. Conservation only makes sense when linked to production
3. Prices and marketing have a key role to play in investment in land

.....one qualification to the landscape level approach sentence: beware 'winners and losers' within a landscape scenario!

Will

Dr WRS Critchley
Coordinator, Resource Development Unit
CIS-Centre for International Cooperation
The Netherlands

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Message 3: from Richard J. Thomas, Thursday 24/03/2005

A contribution from Richard J. Thomas, program Director at the International Centre for Agricultural Research in the Dry Areas (ICARDA).
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Please note that a lot of the points under discussion on land degradation are covered by the Desertification, Drought, Poverty and Agriculture consortium without specific attention to water issues and can be accessed at www.ddpa.net.

I will be happy to try and contribute to the discussion.

Richard J. Thomas

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Message 4- from Felix Kolawole Salako, Thursday 24/3/05
A message from Nigeria

I am Felix Kolawole Salako (PhD). I am a Reader in Soil Physics/Soil and Water Conservation, and current Head of Department of Soil Science and Land Management, University of Agriculture, Abeokuta, Nigeria.

Soil degradation and rehabilitation, with focus on tropical coarse-textured soils, have been of interest to me in the last two decades. I will therefore be highly interested in participating in these discussions. Many thanks.

Felix Salako

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Message 5- from christian valentin –Friday 25/3/05
Christian Valentin, Director of the research unit “response options” IRD-IWMI-INAFRI in ventiane Laos, comments on the need of a set of indicators.

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Dear colleagues,
Just a point: there is a crucial need at the global level of clear and widely accepted indicators of land and water degradation. Up to now, there is no global mechanism (data base and spatial distribution) providing the base line situation and the current trends. The map produced by UNEP and FAO in early 90’s was based on rather subjective basis and has not been updated since then.
Christian Valentin

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Message 6- from Hanspeter Liniger – Friday 25/3/05

Hanspeter Liniger, coordinator of the WOCAT program, presents some achievements of the WOCAT program, and stresses upon indicators used by the GLASOD program and the LADA program.
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Dear colleagues,

Through the WOCAT programme (World Overview of Conservation Approaches and Technologies) (see www.wocat.net) we have in collaboration with over 30 institutions world-wide developed a methodology to document, evaluate and disseminate good soil and water conservation (management) practices. This was initiated as a follow-up of the global assessment of soil degradation (GLASOD) map. We have developed questionnaires to document achievements made in terms of mitigating degradation.

For this we have used some of the indicators used for GLASOD and have developed additional indicators. All the results and the tools are available under www.wocat.net. Together with ISRIC (contact person: Godert van Lynden: Godert.vanlynden@WUR.nl) we are trying to assess both degradation and conservation. Due to the interest of the our partners in the different regions and countries, we have in the past focussed on support the work at national level by first documenting case studies (these days often called "bright spots"). Although we have developed a mapping tool (WOCAT map) that allows to work at different scales for the documentation and evaluation of degradation and conservation, there has so far not been a very high interest to emphasize the mapping.

I would also like to point out that FAO - UNEP has launched the LADA (Land Degradation Assessment) programme with which WOCAT also collaborates. In this programme the question of indicators has been discussed. Please contact Freddy Nachtergaele at FAO or Clemencia Licona Manzur (Freddy.Nachtergaele@fao.org, Clemencia.LiconaManzur@fao.org).
Feel also free to contact us at CDE. Contact person of the mapping is Gudrun Schwilch: gudrun.schwilch@cde.unibe.ch.

Best regards
Hanspeter Liniger Coordinator WOCAT

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Message 7- from Dr Salako- Friday 25/3/05
Dr. Salako brings its experience from Nigeria on trends and options to the debate.
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In response to the questions raised, the following are my views, based on my experience.
Trends and underlying processes
(i) Soil degradation needs to be seen in the context of adaptation of crops
(ii) Rapid decline of soil poductivity for most upland soils have to be related to the coarseness of the soils, as little can be done in altering this, except by "soil reformation". That is, replacing topsoils. Process of soil degradation for gravelly soils does not involve natural loss of topsoil by rainfall alone but includes artificial topsoil removal for gravel/stone mining. This has left vast areas of agricultural land degraded in southwest Nigeria

Promising options
(i) Proper invetory of the extent of soil degradation in relation to ecological features
(ii) Packaging acceptable cropping intensities and fallow management options for farmers. Use of legumes, grasses in fallow and manuring

I will be making further contributions as I get a better understanding of this discussion.
Dr. F. K. Salako
Department of Soil Science and Land Management, University of Agriculture, PMB 2240, Abeokuta, Nigeria

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Message 8- from Don Peden from ILRI on Friday 25/3/05
Don Peden working In Ethiopia brings in his experience from east Africa and stresses upon the massive changes in land use, the land tenure systems as well as common property management practices, conflicts between intensive agricultural systems and livestock management. He also proposes some promising options with crop management, co-management in irrigation systems and institutional strengthening of community based systems.
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Dear Colleagues,

I am Don Peden, and lead ILRI's research programs on sustaining water productivity of livestock systems. I am based in Addis Ababa and focusing primarily on the Nile River Basin. A few thoughts to add to what I have seen so far:

Trends and processes:

1. In this part of the world, there has been a massive change in land use from grazing systems to annual crop producing systems, and this has been correlated with greatly increase soil loss upstream and sedimentation and flooding downstream. One recently completed CA masters research project in the Awash River Basin showed that grazing areas have been reduced by about 50% and annual cropland increased by 125%. The actual shifts has been a bit greater because farmers have abandoned some newly developed steep annual cropland and have returned them back to much lower quality grazing area. Hurni (1989) showed that in Ethiopia, a primary watertower for the Nile, about half of the country is classified as grazing land and that this area accounts for about 50% of the soil loss. The annual croplands cover about 15% of the country, but account for about half of the total soil loss. At least one major tributary of the Nile, The Tekeze River, has experienced significant increases in sediment loads in the past decade, and the country's most important multi-purpose reservoir, the Koka dam, has experienced about a 30% loss in storage capacity since it was constructed.

2. Land tenure in many areas of East Africa is a seasonal phenomenon. Cropland often reverts to open access immediately or shortly after harvest of annual crops. This leads to excessive removal of crop residue by the farmer and by subsequent public grazing. There is neither any incentive for farmers to leave crop residue in his/her fields nor to invest in soil conservation and fertility replenishment under such a system.

3. Community-based management of common property natural resources including grazing land and water resources is often weak or lacking. Very few water users associations address the issue of management of land adjacent to irrigation infrastructure, and this extends to management of livestock in catchments and around riparian areas that could be managed to protect water resources.

4. Evidence suggests that land degradation accompanied by poor animal management particularly near water resources can aggravate transmission of some important diseases such as malaria, cryptosporidium and Fasciolosis.

5. Institutions capable of taking an integrated approach to watershed management are generally weak, but where they function, significant reduction in rates of land and water degradation has occurred. Success often depends on taking a multi-sectoral approach to adoption of several innovations simultaneously.

6. Across sub-Saharan Africa, there has been a general trend toward increased animal densities in areas where agricultural intensification has been taking place. Several reasons can be proposed. For example, Irrigation development is often motivated by a desire to contribute to poverty reduction. If successful, farmers and labourers associated with irrigation systems frequently purchase livestock as a means to accumulate wealth. However, irrigation systems routinely do not provide any provision water, feed and space to enable livestock keeping. Consequently, these animals will often contribute to degradation of the water quality in and near irrigation schemes and to the destruction of irrigation infrastructure such as canals when they endeavor to climb into steep sided irrigation canals to drink.

7. Establishment of irrigation systems in pastoral often denies herders of access to traditional dry season watering and grazing areas and forces them into more restricted and more vulnerable land areas. Apart from the human suffering involved, land degradation often results.

Some promising options:

a) Management of annual croplands in East Africa is vital for not only improving rainfed food production, but to reducing damage to downslope water resources.

b) Effective community-based institutions are needed that can take an integrated watershed management approach.

c) Irrigation planning and development must take into account the needs and positive and negative impacts of livestock on land and water resources including soil nutrient management.

d) Indicators of the impact of land-degradation on animal and human health are needed and these need to be developed and used in collaboration with the veterinary and human health sectors.

I hope this is useful, and I look forward to this consultative process.

Best regards,

Don
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Don Peden
Leader, Sustaining water and nutrient productivity of livestock systems.
ILRI-Ethiopia

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Message 9 - from dr. Ghulam Murtaza- Saturday 26/03/05
Dr. Ghulam Murtaza, Assistant Professor, Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad-Pakistan is going to add few remarks
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Dear Participants,

Followings are some points to be considered

Under Trends and Processes:

1. Priorities should be given to irrigation efficiencies with allowance for salinity/sodicity control to hamper land degradation strategies.
2. Sodicity related fertility issues must also be considered for sustainable agriculture on degraded lands.
3. Absentee landlordism and excessive irrigation is a potential threat for irrigated agriculture. This practice is well established in Pakistan due to lack of Govt. policies.
4. Subsidy provision by governments should be monitored and appreciated to restore wastelands.
5. Organic matter influencing a number of soil quality indicators must be restored on sustainable grounds. How rural masses can integrate to such efforts made by governments.

Under Response Options:

1. Impacts of low quality waters should be correlated with fraction of clays and their nature.
2. Alternatives of marginal quality water usage must be addressed deeply
3. Correlation between salinity/sodicity, organic carbon reserves should be studied together for their long term impact on physical aspects of soil degradation.

Dr. Ghulam Murtaza

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Message 10 from from hans liniger -a complement to message 6 send on Friday 25th

Dear colleagues,

I have sent the message below and I have had some additional thoughts which I would like to add concerning the objective assessment of degradation and conservation. Within the NCCR (National Centre of Competence in Research) North-South programme (www. nccr-north-south.unibe.ch) studies in collaboration with WOCAT have been initiated to assess soil carbon, nitrogen and other fertility indicators by means of reflectance spectroscopy. This allows to map indicators for degradation / conservation for large areas. This assessment is done in collaboration with ICRAF (World Agroforestry Centre)
(see:http://www.worldagroforestrycentre.org/sites/program1/specweb/home.htm
contact address: k.shepherd@cgiar.org).

Best regards
Hanspeter Liniger

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Message 11 from Bancy Mati- Saturday 26/3/05

A message From Bancy Mati from Kenya.
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Dear All,

Hi! My name is Bancy Mati. I am Associate Professor of Soil & Water Engineering, at the Jomo Kenyatta University of Agriculture & Technology (JKUAT) in Kenya. I am an active GIS expert as well. I also work part time as a consultant at the IWMI office in Nairobi.

Here is my contribution:

Trends and processes

(1) What are the costs of land degradation? - in units and terms that make political sense at each level (i.e. farmer, pastoralist, community, government, global).
(2) The most extensive LD, especially in Africa, is found in the rangelands, which also suffer harsh climatic conditions and sparse human populations (lack of labour). It is hard to get solutions that are widely replicable - Or is it not?

Response Options

(1) Ecosystem restoration targeting stabilization of ephemeral and/or depleted water sources is an intervention having positive economic and environmental impacts against LD.
(2) One of the major thrusts of the MDGs being implemented currently targets soil fertility. In what ways can this forum generate enough heat to have a more inclusive LD agenda in the MDGs?

Bancy Mati

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Message 12 &13 - Prof Joshi S.G. – Sunday 27/03/05 & Monday 28/03/05
Prof Joshi S.G. from India agrees with Christian Valentin when he says:
“Just a point: there is a crucial need at the global level of clear and widely accepted indicators of land and water degradation. Up to now, there is no global mechanism (data base and spatial distribution) providing the base line situation and the current trends. The map produced by UNEP and FAO in early 90's was based on rather subjective basis and has not been updated since then”.

It would be interesting if Dr. Joshi S.G. could support his affirmations with evidences/examples from his work.

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his reply on synday 27. YES I DO AGREE!!!
JOSHI S.G
(PROFESSOR / SCIENTIST EMERITUS)
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his reply on Monday 28. yes! I agree with above! There is this baseline need! Let us take some action instead of bothering about evidences/examples!
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Message 14 – from Guy Evers – Monday 28/3/05
Guy Evers, senior agricultural officer of the FAO investment center for southern and eastern Africa comments on the necessary incentives for sustainable land management and the need to assess the impact of tillage. He provides two references (Malawi and Brazil) and two documents about better land husbandry.
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My name is Guy Evers, Agriculturist from the FAO Investment Centre.

A few quick points:

Sustainable Land Management requires incentives. It is common to envisage subsidizing seasonal inputs (mainly fertilisers, see recent recommendations from the Hunger Task Force), but not longer term investments for sustainable land management. Policies tend to favour short-term impact rather than long-term impact, though both are needed. For example, how about subsidizing interventions which would reduce tillage practices, and have positive impact on the environment (see Parana/Sanat Catarina example in Brazil).

Along the same lines, the impact of tillage (expecially disc polowing and harrowing) on land degradation should be considered; hence alternative solutions to plowing (reduced to no-till farming, ripping, one-off sub-soiling during the transition from tillage to no-till farming etc.) should be part of the water and land management issues.

Regards.

Guy Evers

PS: Attached for your information two links and two extracts of documents the authors may wish to consider.
MalawiHoe Pan Investigation:
http://www.fao.org/documents/show_cdr.asp?url_file=/docrep/007/ae369e/ae369e00.htm
Brazil Study Tour 2000: http://www.fao.org/documents/show_cdr.asp?
url_file=//docrep/007/ae371e/ae371e00.htm

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Message 15- from James Chiphampa from Malawi- Tuesday 29/3/05
James Chimphampa from Malawi comments on Deborah Bossio introduction statement “declining soil organics matter have an impact on agricultural production” with examples.
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Dea All,
My name is James Chimphamba and I am a lecturer in Land and Water Management at Chancellor College, Universiry of Malawi and have wide and extesive experience in Water and Soil Conservation, and Catchment Management in Malawi and within the Southern African Region.

While I do agree with Deborah Bossio statement (introduction) that declining soil organic matter has significant agricultural production impacts, my field experience in Malawi, Zambia, Tanzania and Lesotho indicates that smallholder farmers lack skills and knowlege for planning and implementing soil fertility restoration and enhencement mitigation measures in their farming operations.Our considered capacity-building of farming communities in low cost soil fertility restoration measures will go a long way in reversing the observed land degradation trends.
James

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Message 16- from Godert Van Lynden of ISRIC – Tuesday 29/3/05

Godert Van Lynden from ISRIC wishes to clarify concepts and terminology around soil and land degradation, the existing assessment (LADA) and the promising options.
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Dear Colleagues,

My name is Godert van Lynden, working at ISRIC – World Soil Information, mainly on soil and land degradation issues and soil conservation. I have been involved in soil degradation assessments in S. & SE. Asia (ASSOD), and in Central & E. Europe (SOVEUR), and am currently involved in the SOWAP and ProTerra projects focusing on conservation agriculture in N. and S. Europe. Furthermore I am strongly involved in the WOCAT programme (see message Hanspeter Liniger) since 1993 and I have several years long-term working experience in Asia and Africa.


Please allow me the following observations on the discussion so far and the flood of Emails received after the Easter weekend. Have you all been working over the weekend…?

First of all I believe it is essential to specify what we are talking about: some contributors speak of soil degradation, others about land degradation, which is much broader and which is presumably what is intended in this discussion, going by the title of the assessment chapter. Most definitions of land include water by the way, so I am always surprised to see “Land and water”, even in names of divisions or organisations.

Without wanting to start a deep debate about the definition of land degradation here, I’d like to emphasise that what is seen as degradation in one sense may be seen as an asset to others. So degradation should be seen in relation to the (intended or actual) function of the land. A good example is agricultural land being converted into built-up area: a rather underestimated form of land degradation (in the agricultural sense) in my opinion. Land that has retained all its original functions should then be considered as a reference base but in practice this is not feasible. As this Comprehensive Assessment is about water management in agriculture, we should probably narrow our attention to this function of the land while assessing degradation. This may be a rather redundant recommendation, but I believe it is good to have this at the back of our minds during the discussion.

To add to Christian Valentins statement about the need for clear and widely accepted indicators – which touches a bit on my argument above: the GLASOD map Valentin refers to (produced by ISRIC by the way) is indeed outdated and moreover only addresses soil degradation. The argument that it was subjective is only relative: it was prepared on the basis of consultation of ± 300 experts worldwide who supposedly based their opinion on the data available to them. This “expert opinion” approach is still a valid approach for a rapid and broad-scale assessment and could – or should - be combined with more sophisticated methods now available. In this context I also may refer to the LADA programme, implemented by FAO (another land degradation assessment!).

Finally, to respond to the second discussion issue (“What are the most promising options …”): the WOCAT programme, as referred to by Hanspeter Liniger, has indeed developed a methodology for a comprehensive documentation of field case studies of soil and water conservation. The WOCAT database currently has 126 Technology case studies and 71 “Approaches” from a large number of countries worldwide (and a lot more “raw” material needing updating or validation), containing some very useful material for this assessment. Furthermore, the WOCAT methodology is a good basis for further data collection of promising examples of good water management.

Kind regards

Godert

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Message 17- From Kenneth Cassmann, Tuesday 29/3/05
Kenneth G. Cassmann, from Nevraska University in the USA contributes to the debate on the scope of the land degradation debate and suggests that the crop yield supported by a soil quality without any nutrient inputs from external sources (including commercial fertilizers or imported organic matter or manure) be the measure of land. He finally comments on the two leading questions of Deborah Bossio. A paper is contributed to the discussion and posted on the CA website (cassmann, 99).
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Dear Colleagues,

My name is Ken Cassman and I'm a professor of systems agronomy at the University of Nebraska. I've previously worked at IRRI in the Philippines,and have held posts in Egypt's Nile Valley and the Brasillian Amazon region. Although I haven't worked in sub-Saharan Africa, I have reviewed IITA's programs in that region and am familiar with CIMMYT's research efforts in Africa.

Before addressing the two questions that Deborah Bossio proposed to initiate this discussion, I would like to respond to those who have called for more quantitative and objective measures of land degradation. As noted by others, such measures depend on the intended function of the land.

If we assume that land degradation is tightly linked to soil quality, it has been widely proposed that soil quality serves three basic functions:
(1) it supports productivity of crop/fiber/forage system;
(2) it provides habitat for a wide range of organisms, and thus is a matrix for biodiversity;
(3) it serves as a filter or detoxifying matrix for water and reactive compounds.

While it is true that all of these functions are important, taken together they have inhibited the search for a unifying land degradation parameter because of the seemingly opposing nature of the three functions. For example, soil biodiversity is often greatly reduced when a natural ecosystem is converted to agriculture.

However, if we are talking about agricultural land that will remain in agriculture, it seems that those soil properties that enhance any one of the three functions listed above also enhances the other functions. That is, it is very difficult to identify changes in soil physical, chemical, or biological properties that improve productivity of the agroecosystem (such as greater soil organic matter or reduced soil compaction) which would have a negative impact on a the role of soil as habitat or as a filtering matrix.

If the above supposition holds broadly with few major exceptions, then it becomes much easier to identify a unifying measure of soil quality because one can focus on something that is easily measured. To that end, for agricultural land, I would propose that the crop yield supported by a soil without any nutrient inputs from external sources (including commercial fertilizers or imported organic matter or manure) be the measure of land quality. While it is clearly a productivity-driven parameter, I suspect that changes in soil properties that positively or negatively affect its ability to support crop yield without nutrient inputs would also affect soil function as habitat or as a filtering matrix in the same direction.
In rainfed systems, such a yield measure could also be normalized for the amount of available moisture.

Note also that such a measure of soil quality can be easily explained to farmers because quality substitutes for inputs (see Cassman, 1999, Fig 3, paper available on the CA website). That is, soils with higher inherent quality require fewer inputs to achieve the same yield. Similarly, degraded soils require more inputs and have higher unit production costs than non-degraded soils.
Hence, soil quality can be given an economic value and explained to farmers and policy makers in economic terms.

Finally, the two questions: 1) What are the most important (and underappreciated?) trends and underlying processes with respect to land degradation and water management for agriculture? There are two major types--one appreciated and one relatively obscure but also important. The first is degradation due to increased cropping intensity in regions with poor soils and/or harsh climate that cannot support intensified cropping, and where the necessary inputs required to overcome the poor soil quality (nutrient inputs or lime, for example) or harsh climate (irrigation) are not available for whatever reason. This type of degradation is widely recognized and is occurring in much of sub-Saharan Africa and the harsher environments of south and southeast Asia. The second type occurs in regions with initially good soil quality and high potential productivity where intensive agriculture causes more subtle forms of degradation. Slow loss of organic matter, erosion, nutrient depletion, increased pest pressure due to lack of rotation and diversity in the cropping system are examples. This form of degradation is poorly understood and not well appreciated, and is difficult to measure because it requires a long-term study to quantify trends.

2) What are the most promising options available to address negative trends in land degradation, and thereby conserve and improve the management of water? The answer to this question depends on the specifics of the system in question. In all cases, however, the key to reversing degradation is to have a thorough understanding of the processes involved.
It also helps to have quantitative measures of the economic benefits of reversing degradation, and to this end the unifying measure of soil quality proposed above is very helpful.

(See attached file: Kenneth cassmann_kgc Ecol Intensification PNAS 1999.pdf available on the website (discussion and contribution/contributed documents)

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Message 18-from Patricia Kabatazi-Wednesday 30/3/05
Patricia Kabatazi, environmentalist reacts on the message posted by Gobert Van Lynden (message 16) where he clarifies concepts and terminology around soil and land degradation, the existing assessment (LADA) and the promising options. She refers to a case study around Lake Victoria

(Patricia, do you have any supporting document that describes this case?)
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Promising options supplement.

A case study around L.Victoria.

Environmental issues should be put back in place like replanting trees and restoring wetlands especially season wetlands. Inorder of minimising soil erosionand increase plant cover.

Kabatabazi Patricia
Environmentalist.

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Message 19-from Patricia Kabatazi- Wednesday 30/3/05
Patricia Kabatazi reacts to the message of Will Critchtley (message 3) where he provided additional points for discussion on trends and options.
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Addition options.

Environmental Impact Assement should efforced to be done in a very community small activities to minimize problems which collectively form big problems today,tomorrow and future.

Kabatabazi Patricia
Environmental Impact Assessmentor/Trainer

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Message 20 – Message from Deborah Bossio - summary of first week– Thursday 31/3/05
Deborah Bossio summaries the first week of discussion and would like your feedbacks, reactions on what is suggested thereafter.
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Dear All,

There has already been a very substantive response to the discussion, and I appreciate very much the variety of views that have been put forward.

Two important points that appropriately should be included in the introduction of the chapter were raised:

1. Terminology. We do need to use consistent terminology and define it for use in the Assessment. I propose, as suggested by Godart, that we use land in the broad sense to include the soil, water, plant and animal resources, and that we be careful to use soil or water when referring to those resources singly.

2. Scope: Our focus is on degradation as it relates to supporting agricultural functions of land, we should make this explicit, to help limit the scope of the discussion.

Below I have attempted a summary of issues and ideas raised thus far as a starting point for further contributions. Please continue to contribute new ideas, but also critique this growing list, are some more relevant or more pressing than others?

Trends and Processes

• Land degradation is inadequately monitored which is impeding implementation of national and international development goals. There is a crucial need at the global level of clear and widely accepted indicators of land and water degradation. Up to now, there is no global mechanism (data base and spatial distribution) providing the base line situation and the current trends.

• Declining soil organic matter is related to, and probably exceeds in extent, all other degradation processes and has significant impacts on productivity, resilience of agroecosystems, local and regional water cycles, and global C cycles.

• Soil erosion and sedimentation are a major cause of failure for investments in water infrastructure, limiting on site productivity, reducing useful life of storage facilities, and increasing costs of infrastructure maintenance.

• One-way nutrient flows in regional and global food trade are a significant driving force of nutrient depletion and water pollution.

• People and demographics have a huge and not easily predictable impact on LD. Must be understood and are crucial in any 'remedy'.

• Massive land use change from grazing systems to annual crop production observed in SS Africa underlie greatly increased upstream erosion and sedimentation and flooding downstream.

• Energy needs of the rural population - if not met from outside - lead to consumption of biomass and reduction in SOM and fertility.

• Cropping and tillage practices followed by water erosion are not the only important causes of soil degradation and erosion, gravel/stone mining, construction of roads and other infrastructure cause significant erosion and must to taken into account when designing interventions.

• Irrigation efficiencies, salinity and sodicity problems are very important area of interaction between soil and water degradation, which threaten large areas of irrigated lands.

• Insecurity of land tenure, seasonal fluctuations in land tenure, and absentee landlordism often lead to land degradation. Lack of community-based management of common property resources including grazing land leads to degradation.

• Development of water infrastructures without attention to multiple uses of water leads to degradation of the surrounding resources. Increased livestock densities that often follow agricultural intensification in SS Africa for example, leads to degradation of water quality and overexploitation of nearby land resources. Establishment of irrigation systems that deny herders access to traditional dry season watering and grazing increases pressure on vulnerable areas, causes human suffering, and also leads to land degradation. Evidence suggests that land degradation accompanied by poor animal management particularly near water resources can aggravate transmission of some important diseases such as malaria, cryptosporidium and Fasciolosis.

• The most extensive LD, especially in Africa, is found in the rangelands, which also suffer harsh climatic conditions and sparse human populations (lack of labour).

A useful way to structure the topic might be to focus on two important trends in soil degradation:

• The first is degradation due to increased cropping intensity in regions with poor soils and/or harsh climate that cannot support intensified cropping, and where the necessary inputs required to overcome the poor soil quality (nutrient inputs or lime, for example) or harsh climate (irrigation) are not available for whatever reason. This type of degradation is widely recognized and is occurring in much of sub-Saharan Africa and the harsher environments of south and southeast Asia.

• The second type occurs in regions with initially good soil quality and high potential productivity where intensive agriculture causes more subtle forms of degradation. Slow loss of organic matter, erosion, nutrient depletion, increased pest pressure due to lack of rotation and diversity in the cropping system are examples. This form of degradation is poorly understood and not well appreciated, and is difficult to measure because it requires a long-term study to quantify trends.

Response Options

• There are a variety of approaches that could be combined and applied to improve our current assessments; they include rapid appraisal of soil carbon; comprehensive documentation; expert opinion.

• A simple and unifying measure of soil quality, i.e. crop yield without external inputs and adjusted for rainfall is proposed as a useful basis for a quantitative and objective measure of soil degradation. Indicators of the impact of land-degradation on animal and human health are needed and these need to be developed and used in collaboration with the veterinary and human health sectors.

• Rehabilitation of degraded soils is a key entry point for increasing the productivity of water in agriculture.

• Intensification of smallholder farming systems through reversal of land degradation is already contributing to increased food security and providing other ecosystem benefits in many localized “bright spots”; further investments in this sector are an important response option. For example, improved management of annual cropping systems in East Africa is vital for not only improving rainfed food production, but to reduce damage to downslope water resources. Requirements to achieve this might include packaging acceptable cropping intensities and fallow management options for farmers, and other capacity building efforts to increase farmer knowledge.

• Quantifying economic benefits of reversing degradation is useful, i.e. what are the costs of land degradation? - in units and terms that make political sense at each level (i.e. farmer, pastoralist, community, government, global).

• Appreciation of the full range of ecosystem service benefits that are achieved from investments in rehabilitation of degraded lands can unite agriculture, water and environment sectors to increase the base for necessary investments. For example, Management of annual croplands in East Africa is vital for not only improving rainfed food production, but to reducing damage to downslope water resources.

• Landscape level approaches that take into account multiple stakeholders, and connectivity of landscape components, are necessary to sustain productivity, livelihood options and resilience of agro-ecosystems.

• Land degradation should not/ cannot be isolated from broader rural development packages/ programmes

• Conservation only makes sense when linked to production.

• Prices and marketing have a key role to play in investment in land.

• Effective community-based institutions are needed that can take an integrated watershed management approach, and irrigation planning and development must take into account the needs and positive and negative impacts of livestock on land and water resources including soil nutrient management.

• Alternatives of marginal quality water usage must be addressed deeply.

• Ecosystem restoration targeting stabilization of ephemeral and/or depleted water sources is an intervention having positive economic and environmental impacts against LD.

• One of the major thrusts of the MDGs being implemented currently targets soil fertility. Efforts could focus on generating enough heat to have a more inclusive LD agenda in the MDGs.

• Restoring wastelands is a priority for government subsidy support.

• Incentives which encourage reduced tillage practices would target both sort-term impact and long-term impact that are both necessary for sustainable land management, given the strong impact that tillage practices have on soil degradation.

We also had a number of suggestions for websites and groups with documentation to support these conclusions. These can be found on the website.

We will run this first discussion through April 4th. After which a summary will be distributed and presented at the Comprehensive Assessment Coordinating Lead Authors’ workshop in Aleppo, Syria.

Thank you for your contributions.

Best regards,
Deborah

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Message 21-from Godert Van Lynden from ISRIC- Thursday 31/3/05
Godert van Lynden comments on the summary message of Deborah Bossio (20). In particular he comments on the statement about organic matter decline, the use of crop yield as an indicator of soil quality, the need for indicators of the impact of land degradation, and additional points about the scoping of the discussion that need to be clarified. He expects other participants to react also.

(Please note that we have created a specific email for that discussion – let me know if you encounter any problems in receiving the messages. thanks)

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Dear Debbie and Domitille,

Thanks for this useful summary. I agree with many of these excellent points but would like to make a few comments (which may well provoke the same from others!):

? I think the statement about the extent of organic matter decline (NB: a soil degradation process) is largely based on assumptions that may well be true. But as indicated elsewhere in the summary, we currently lack (global) data about the extent of land degradation, so we cannot yet support this assumption with hard facts. I personally believe that erosion – though probably the most important degradation type worldwide indeed – is generally overestimated and organic matter decline often underestimated, like several other degradation types. But we need a proper assessment and monitoring system to prove this (or the opposite).
? Using crop yield as an indicator of soil quality and hence for degradation is a good possibility (we did the same for the ASSOD project) but under a number of at certain conditions, because crop yields are obviously influenced by other “external” factors than (degradation of) soil quality: pests and diseases, climatic fluctuations and weather influence (not just rainfall) and farmer priorities, which may also change over time. Moreover, using crop yields as an indicator requires a reference value, i.e. what would a “normal” yield be (or do we take optimum potential yield for a given soil/land type as a reference?). Last but not least: how to compare yields of different crops, in case of rotations in temporal comparisons or between different areas in spatial comparisons? I must admit we didn’t address all these issues in the ASSOD project and faced some of the mentioned problems due to that.
? “Indicators of the impact of land-degradation on animal and human health are needed”: for our soil degradation assessment in C. and E. Europe (SOVEUR), where soil pollution was an important issue, we tried to address this in two ways: by assessing the degree of pollution in terms of concentration of toxic substances and secondly by (qualitatively) assessing the impact on human and animal health, on plant growth and productivity or on the entire ecosystem and biodiversity. See http://www.isric.nl/Docs/SOVEUR_Rep97_08.PDF,in particular p.11-13. But I agree that the need for more quantitative indicators remains.
? What is the starting point in time when assessing degradation: are we looking at a relatively short term, e.g. degradation in the past two decades, medium term (past century or so) or historical (> 1 century)? I would personally favour the first option, otherwise it is a bit like comparing apples and oranges (two different crops! See remark above)
? “gravel/stone mining, construction of roads and other infrastructure cause significant erosion and must to taken into account” – but our focus is on agriculture. Or am I hairsplitting? I am aware of the danger of isolating an issue and simplifying it by ignoring related problems (like the one mentioned here).
? “Massive land use change from grazing systems to annual crop production observed in SS Africa underlie greatly increased upstream erosion and sedimentation and flooding downstream.” But a few points below we see that “The most extensive LD, especially in Africa, is found in the rangelands”. Isn’t this in contradiction?
? “Appreciation of the full range of ecosystem service benefits that are achieved from investments in rehabilitation of degraded lands can unite agriculture, water and environment sectors to increase the base for necessary investments.”. This is exactly one issue addressed by our new “Green Water Credits” initiative about which I may make a separate contribution with my colleague Sjef Kauffman. (Click the link for more information)
? “Conservation only makes sense when linked to production.” I am not too sure about the “only”: there may well be other (socio-economic) benefits, such as labour efficiency, increased water availability, reduced fuel costs (e.g. in case of mechanized min. tillage), etc. Maybe this should read “only makes sense when linked to increased income”, but even that I doubt a bit.

I think that’s enough for the moment. Don’t take any of my remarks as criticism, but either as a challenge or as ignorance!

Kind regards

Godert

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Message 22 – message from james Chimpamba- Thursday 31/3/05
James Chimpamba comments on the conclusions of Deborah Bossio and stresses on the need to start from the packaging of best practices tested in sub-saharan Africa.
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Dear All,
Let me register my appreciation for a very comprehensive summary of our discussion on Land Degradation. However, I am inclined to thinking that packaging of proven measures or best-bet practices which has so far been identified for the sub-Saharan region for effective smallholder capacity-building should be the entry point for reversing current trends on land degradation. This is further supported by your identification of “intensive cropping” in the sub-Saharan Africa. However, the issue here is not “ intensive cropping” per say, but use of inappropriate practices of "intensive cropping", mainly as a result of inadequate or lack of skills and knowledge for sustainable practices.

Regards,

James Chimphamba

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Message 23-message from Sarah Scherr- Thursday 31/3/05
Sarah Scherr, Director of Ecoagriculture partners comments on the scope proposed for the CA-land degradation chapter. She recommends to put it in a broader contect.
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Deborah and Domitille,

I appreciate that the focus of this particular exercise is on land degradation in relation to the agricultural functions of land. But it seems to me that both problem analysis and development of action plans for this should be framed within the broader context of the multiple functions of agricultural land. In many parts of the world, lands used for agriculture are also critically important for watershed protection functions, for biodiversity conservation, even landscape beauty and carbon sequestration/storage. Options and strategies for actions to combat land degradation will differ markedly for sites where such potential co-benefits of land protection and rehabilitation are present.

Sara

Sara J. Scherr, Ph.D.
Director, Ecoagriculture Partners
Forest Trends
1050 Potomac Street, N.W.
Washington, D.C. 20007 USA
www.ecoagriculturepartners.org

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Message 24-from L. Thiombiano from FAO – Thursday 31/3/05
DR. L. Thiombiano from FAO-africa office stresses upon three issues about land degradation.
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Dear Colleague,

Based on the on-going discussion, I would like to emphasis on three aspects:

1. The interelation between water erosion and wind erosion has a great impact on water availability and management particularly in Sahel zone

2. The quantitative impact on land degradation on the availability of water at watershed/river basin levels is not yet well known

3 . Land Degradation Assessment (LADA) methodological framework as developed by FAO in collaboration with various partners could be a synergic platform for a global effort in the evaluation, updating and monitoring the extend and impact of desertification. During the round of sub-regional workshops organized by the UNCCD Secretariat in collaboration with ECOAWAS-CILSS, UMA, CEMAC, IGAD, SADC, GM... all african countries pointed out the need for an appropriate assessement tool to:
- Evaluate the impacts of projects and programmes related to land degradation at national and sub regional levels, so as to disseminate the experiences gained and contribute to the replication of success stories;
- Build capacities to enhance data collection, collation and analysis while making use of the subregional and regional Institutions, and the LADA methodological framework.

Best regards,
Dr L. Thiombiano
Senior Soil Resources Officer
FAO, Regional Office for Africa
E.mail : lamourdia.Thiombiano@fao.org

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Message 25-from Peter Hobbs – Thursday 31/3/05
Peter Hobbs recommend to look also at conservation agriculture. It has shown very effective results in south America particularly.
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Dear All: I am surprised that there has been very little mention of conservation agriculture -- essentially zero-till and residue or cover crop mulch in this discussion on degradation. There has been a significant adoption of this management system, especially in South America over the past decade by farmers with positive results in terms of reducing erosion, improving water use efficiency and higher yields with less inputs and less greenhouse gas emissions. There are a number of web sites that are reporting these results. I use the FAO one at http://www.fao.org/waicent/faoinfo/agricult/ags/AGSE/Main.htm where there are also many links.

The other factor that has received very little mention is degradation related to below ground biology. One farmer in Brazil has used zero-till and mulching for 27 years and now gets higher maize yields with half the fertilizer he used to use. This must be a result of better nutrient recycling and biological activity, although maybe weed control and better varieties also play a role. Promoting improved below ground bio-diversity would be important for restoring soil health -- physical and biological. CA described above is probably helping promote healthier soil through minimal disturbance and the beneficial effect of the surface mulch. Maybe this practice and key soil health factor need to be considered in your discussions. Modern agriculture based on tillage and bare soils is definitely not a sustainable practice. Hope this adds some food for thought.

Peter

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Message 26 : from Kolawole Saloko- Friday 1/4/05
Kolawole Saloko shares the point of view of Godert Van Lynden (21). He adds a comment from his experience in Nigeria. (M. Salooko do you have any detailed case to share with us to strengthen you point?)
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I wish to state that the points raised by G. van Lynden on narrowing our discussions, based on correct definition of terms is very pertinent. This is in respect to "soil" and "land". I must, however, note that some people who work on soil degradation/soil conservation also relate this to water (surface/underground) pollution. Thus, discussants may not really be far from the point when they use the term "land degradation"

Also, in my earlier contribution, I alluded to the fact that soil degradation can be relative to crops, eg., maize vs cassava. This is probably still in context of land use and land degradation mentioned by G. van Lynden.

From my experience in Nigeria, the moment you loose the topsoil, you have problems with soil water/nutient utilization by crops; root growth becomes poor anyway. In this respect, soil degradation is linked to soil water management in crop production.

Dr. F. K. Salako
Department of Soil Science and Land Management
University of Agriculture
PMB 2240, Abeokuta, Nigeria
Additional E-mail: kolawolesalako@hotmail.com

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Message 27 – from Salako – Friday 1/4/05
M. Salako reacts on the summary of Deborah Bossio.
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I wish to register my appreciation of the summary of the discussions on Land Degradation. However, I want to correct an impression that when we talk about land uses other than agriculture, we are not addressing land degradation in relation to agriculture. This is not true. For instance, stone/gravel mining talked about occurs on vast agricultural lands, resulting in land degradation. It reduces the capacity of rural communities to grow crops and eventually leads to further deforestation or cropping intensification on limited available land, and this promotes land degradation.
Dr. F. K. Salako

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Message 28- from Freddy Nachtergaele in FAO-soil service- Friday 1/4/05
Freddy Nachtergaele (LADA, FAO) comments on the summary points of Deborah Bossio and following statements.

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On organic matter decline quoting from a recent message from Peter Loveland:
"I think the important point is that very few countries have sufficient long-term data from different land-use systems (I don't regard the few long-term sites e.g. Rothamsted as being representative in either the spatial or temporal sense)to be entirely certain what the pattern is. No-one would reasonably expect to compare forestry to arable or even to long-term grassland. However, the data from England and Wales FOR THE SAME LAND-USE SYSTEM show that carbon is being lost from all systems to a greater or lesser extent. These data come from the National Soil Inventory (almost 6000 sites sampled in about 1980) and resampled at 15-20 year intervals. ... Quite why all systems are losing carbon is open to debate. The losses of C are roughly in proportion to the total C, i.e. the more C you have to lose, the more of it goes. Thus long-term arable cultivation loses very little - the situation is at equilibrium (or near enough). Managed grassland is losing more - perhaps due to greater stocking density, more frequent cutting for hay/silage, more use of N. BUT why the losses from peats, moorlands, 'rough grassland' forests ? A first approximation is that these more carbon-rich soils have a greater proportion of 'labile C' and this goes first. We surmise that C-loss might have something to do with warmer years in the last 20; my own view is that warm winters are more important than warm summers because the topsoils (with the greatest amount of labile carbon) remain wet enough for microbial decomposition to continue throughout the winter. In the summer, the topsoils become much drier. However, we don't know. Interestingly, a separate and completey independent survey in the UK (Countryside Survey 2000, which has run since about 1972) has found an exactly similar pattern across all land uses." UNQOUTE
On "objective" and "subjective" measurements of land degradation: it is an easy way out to dismiss studies like the GLASOD one as being subjective without proposing an alternative nor mentioning the problems inherent to measured "objective" data such as organic matter decline, which range from analytical errors over the site variability to ignoring the fact that not there are different types of organic matter, not all of them "good" . On the other hand efforts to quantify land degradation for the last twenty years have nearly exclusively focussed on monitoring (by remote sensing) land cover changes, which hardly give a full picture, ignore the socio-economic driving forces and result in generalizations that forests are "good" and agriculture is "bad".
The lack of a baseline for soils globally as flagged by Valentin is indeed a major obstacle. Estimates of costs involved, based on the forest soil inventory of the EU vary between 5000 and 25000 US$/ site. An alternative suggested by LADA is the Visual Soil Assessment which can be carried out at 1% of this price. More info on LADA from the LADA Virtual Centre: http://lada.virtualcentre.org/pagedisplay/display.asp
Particularly in the context of water resources it is extremely important to relate on-site degradation and off-site effects which are not necessarily negative.
Dr. Freddy Nachtergaele
Technical Officer Land Classification FAO HQ Rome

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Message 29- from Kolawole Salako- Friday 1/4/05
Kolawole Salako completes his previous message with interesting indications on his projects and publications.
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We (myself and co-authors) have a number of publications based on studies carried out on a degraded (mechanically cleared and eroded for a number of years) Alfisol while I was in IITA, Ibadan, Nigeria. There was a project on the " Regeneration of a degraded Alfisol" in which I was involved between 1991 and 1997. There was also an attempt to manage some plots which had undergone series of soil erosion studies between 1983 and 1992 with herbaceous legume after short fallow allowed up to 1996 . These experimentss included studying agronomic and fallow management parameters (soil, root growth, above-ground buiomass and crop yields), and afforded understanding short-term and long-term effects of soil degradation. A few of tour publications can be found in:Soil Use and Management 13: 130-136, 16: 183-188; 17: 41-47.

I also established two projects at the University of Agriculture, Abeokuta between 2001 and 2002. The first looked at upland rice growth on soils at different levels of degradation by water erosion and the second on effects of previous soil degradation by mechanical tillage on maize growth. Between 2003 and 2004, I worked with some students on the effects on topsoil removal (artificial desurfacing) on maize growth, focusing on soil strength and root growth.

My experience with these infomed my reference to gravel mining and soil degradation, even though it might be a local problem. For this gravelly Alfisol, I used visual observation of gravel distribution on soil surface in one of the experiments to classify soil degradation levels based on my experience and soil survey data that gravel would naturally occur in higher concentration within the subsoil. This classification eventually proved effective from results of soil analysis and agronomic data. Although the gravel serve as "rock mulch", they impede tillage operations even with hand hoes and make application of organic and inorganic feertilizers ineffective.

Soil strength is increased by loss of topsoil and this was a major hinderance to nutrient utilization by crops, as root growh was effectively impeded.
Dr. F. K. Salako

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Message 30- from Sjef Kauffman and Godert Van Lynden- Monday 5/4/05
Sjef Kauffman joins the online discussion and comments with Godert Van Lynden on Deborah Bossio statements (20): (i) LD is inadequately monitored, (ii) people and demographics have a high and not easily predictable impact on LD, (iii) massive land use change from grazing systems to annual crop production observed in SS Africa, and (iv) prices play a key role.
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Dear Domitille and Deborah,

I am sorry that I can only join the interesting Land Degradation (LD) debate now. Thanks to Deborah’s summary it is possible to make remarks on the debate. I have asked Godert van Lynden to join these observations as he has followed the debate so far (trusting we prevent repetitions in the observations below to what has been said before).

Below a few remarks on the statements: (i) LD is inadequately monitored, (ii) people and demographics have a high and not easily predictable impact on LD, (iii) massive land use change from grazing systems to annual crop production observed in SS Africa, and (iv) prices play a key role.
I agree with these statements, but I have the feeling that we should highlight more the pivotal role of people- specifically farmers and politicians- and the operational consequences, because farmers will be the main implementers of returning a negative LD trend and politicians need to develop supporting policies.

I like to restrict the observations to rainfed agriculture, which is and will be the dominant form of agriculture viz irrigated agriculture, especially in SSAfrica.

The societal and environmental effects of land degradation such as soil erosion and the role of the farmers are still insufficiently recognized by politicians. Some reasons and operational directions:

Firstly, clear examples of man-induced erosion are still seen in many countries as a reality given by nature. Probably this ‘blindness’ for human–induced degradation is on the one hand caused by the often slow and gradual character of degradation (the ‘second’ type of degradation). Therefore yes, we need a real time/trend monitoring system. Please note that such a tool has recently been proposed by ISRIC and Centre for GeoInformatics of Wageningen UR in the LADA project (finally a successor to the much used but outdated GLASOD). On the other hand scientists have not adequately translated degradation into hard economic figures. Moreover researchers are not unambiguous on the LD subject. This ambiguity was illustrated during the seminar “Soil degradation in Sub-Sahara Africa” held at ISRIC in March 2002. Scientists presented and discussed strongly opposing opinions whether land degradation is a serious issue or not. See for more details the special issue on Soil degradation in Sub-Sahara Africa in Land Use Policy, 2005, Vol.22, No.1.

Secondly, farmers play a key role in the quantity of runoff through their soil and crop management. Whether water will infiltrate into the soil or not and become runoff is strongly determined by land use and soil management (and of course conditioned by site-specific biophysical conditions of climate, terrain and soil type). Runoff is a main factor determining water erosion. Although this seems to be an open door, most politicians are not or insufficiently conscious of this. And also here, hard (biophysical and economic) figures on situations with and without runoff are lacking for politicians to develop proper policies to stimulate investment in soil and water conservation. We need a quantitative standardized tool to predict the effect of farmer’s soil water management on water balance components. Recently a procedure has been developed to calculate the water balance, i.e. “green and blue” water flows for annual crops at farmer’s field and accrued at regional level under various scenarios of soil and water management. This tool is based on currently available data sources of soil and terrain (SOTER), climate (FAO-AMDASS) and soil and water conservation (WOCAT). For details on this Green and Blue water management tool, see the Green Water page on the ISRIC Website.

Thirdly, on the topic of prices playing a key role, again a reference to the Special Issue of Land Use Policy (2005, Vol.22, No.1.). In particular to the paper presented by Niek Koning and Eric Smaling “Environmental crisis or ‘lie of the land’? The debate on soil degradation in Africa”. Present politics foster taxing farmers rather than supporting farmers to allow gradual intensification in a world of low international prices. In this situation, population growth causes downward spirals of poverty and soil degradation rather than sustainable intensification. These dynamics cannot be changed by participatory approaches alone: public investment in infrastructure and a reversal in price policies are also needed.

Fourthly, in the implementation of SWC, more focused “green and blue water optimizing” techniques could play a role to generate additional income for farmers. Recently a Green Water Credits (GWC) research and implementation project was proposed by IFAD and ISRIC. GWC makes additional income available for farmers as a “bonus” for implementing improved water management that (mainly) benefits downstream areas. GWC can play a leverage role to make the necessary investments in soil and water management, because we may not soon expect drastic changes in the world market prices of agricultural commodities. For details on GWC see the Green Water page on the ISRIC Website.

With best regards,

Sjef Kauffman and Godert van Lynden

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Message 31: from Patrizia Kabatabazi- Monday 5/4/05
Patrizia Kabatabazi adds some elements to her previous message (17). The research is still being compiled so not yet available.
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The research I referred to on Lake Victoria is a research which was done in support of Regional Land Management Unit found in Nairobi, and the work is being compiled.

Patricia.

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Message 32: from Deborah Bossio –Tuesday 6/4/05
Deborah Bossio wishes to close the discussion for the moment but invite you to come back online from the 25rd of April where a new debate will be launched.

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Dear Land Degradation Chapter Network,

Thank you all for your active participation in this 1st email discussion.
From my point of view it has been very productive and interesting.

The next stage of the CA process is for the lead authors, myself, Bancy Mati, Will Critchley, and Godert van Lynden, to prepare an outline of the chapter. The outline will be presented at a CA writing workshop in Aleppo, Syria April 8-10, where all chapters in the Assessment will be discussed and reviewed for scope and content.

Following the Aleppo meeting the lead authors will again revise the outline, which will be shared with all of you, and the 2nd email discussion “Outline and evidence” will begin. This discussion is currently scheduled to begin on April 25th.

I look forward to continued input from all of you as the chapter develops.
Please note that the current discussion is now closed. Any comments sent to the discussion during the next three weeks will be sent out during the next open discussion phase.

Thank you again for you participation.
Best regards,

Deborah Bossio


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