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Got questions on SLM? Ask our platform experts. This new feature enables you to discuss, online, with experts or view Q&A from others.  For this season, you can connect to 6 experts in the following subject areas: “Conservation Agriculture”; “Smallholder Irrigation”; “Rainwater harvesting”; “Cross slope barriers”; Soil Fertility Management”;  “Land Restoration”; “Agriculture Extension”; “Agroforestry”; “Soil Carbon and Carbon market”.  

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Featured questions and answers

Amy Bea, March 27, 2017 12:38 pm
Dear Cyrille, I am glad to see that TerrAfrica is opening up this discussion space. Good to "meet" you online. In recent years, we have seen and heard many advocates on the good things about agroforestry, and the various benefits (to soil, to farmers, to crops, to rural energy, etc). My first question to you on this topic is that these advantages have been known for decades (by farmers and researchers), why is it not widely used? What are the major bottlenecks to its application? (identifying the right bottleneck is important in designing proper support to scale it up, right?)
Comments 3 Votes 1 Like  Tags:none Answer/Comment
William Critchley, March 28, 2017 5:47 am
Dear Amy, While awaiting Cyrille's reply, may I say I am also very pleased this platform is open for business and communications are starting. Without wishing to contradict you, I did some research in both Kenya and Burkina Faso a few years back and found an increase in on-farm trees (i.e. agroforestry) BUT at the expense of natural forest. Which areas are you thinking of in particular where agroforestry is hard to find and needs promoting? Kind regards, William Critchley Comment
Cyrille Hicintuka, March 28, 2017 11:32 am
Dear Amy Bea
As you say, the advantages of agroforestry are known by farmers and researchers. However, several improvements are required before its implementation at a larger scale. Technical and financial constraints and the cultural importance context should be deeply analyzed in order to understand the behavior of our population in adoption of agroforestry practices.

We have first to show the importance of these practices, the benefits brought by these innovation in terms of figures, the organization of the agroforestry value chain in term of money. We have to get also technical and and financial support.
Although ecosystem services are known, it is not easy to understand their scientific depth nor the environmental scope of this. We need more dissemination of information, agroforestry sites that highlight anything that can improve the socio-economic conditions of small farmers. In this way, the probabilities of conversion to agroforestry are maximized. There is also a need for infrastructure to market agroforestry products.
On the other hand, a very high proportion of farmers in economically disadvantaged countries are not landowners. The lack of property rights limits the adoption of agroforestry (Caveness and Kurtz, 1993). The main reasons for this are the lack of available resources, insecurity in terms of future access to land, and the restrictions on plantation imposed on tenants (Neef and Heidhues, 1994).
May be we will continue this discussion tomorrow
William Critchley, March 29, 2017 1:46 am
Dear Cyrille, Amy,
All sound points by Cyrille, but I believe we can be optimistic on many scores - notably on the basis of what small scale land users have achieved themselves over the last 25 years. I mentioned some research I had done on uptake of agroforestry: have a look at You'll find extracts of the video there. Here's the brief blurb from Camilla Toulmin of IIED (quote from websites):

Twenty years ago, we noticed that some new projects across dryland Africa were attracting a lot of interest for their positive impacts on restoring degraded soils and building more resilient cropping systems. I had recently set up the Drylands programme here at IIED, and was working in partnership with Oxfam’s then-newly established Arid Lands Information Network (ALIN), led by drylands expert, Ced Hesse. We produced a video and booklet — Looking after our land — under the direction of Will Critchley from the Free University of Amsterdam. It showed the growing evidence that simple, low cost soil conservation measures can empower local farmers to restore their lands and improve the fertility of their soil.

Nearly twenty years on, we were keen to find out whether the dryland projects had been a ‘flash in the pan’, or the foundations for a better way of managing soils and landscapes. We asked Will Critchley to go back to look at two of the six original sites from Looking after our land — one in Machakos District, Kenya and the other on the central plateau of Burkina Faso.

Sometimes you can be disappointed going back to places you knew long ago — but this time there was no need to worry. In both cases, both soils and plant cover have been clearly restored, with greater investment in trees of all sorts. By following a participatory approach, in which people learn together about better ways to care for their soils, much has been achieved. Many farmers now harvest enough grain to meet all their needs, with extra to sell.
Zaka Mawoko, March 23, 2017 9:29 am
Dear Dr. Critcheley, My name is Zaka, a junior technical advisor for a project involved in restoration of degraded and deforested land at the continental level. To answer your two initial questions; is it correct to say that yes I agree with land tenure in keeping the land healthy? This, because now land is marked with clear ownership and responsibility and accountability can be taken, this places the onus of any degradation on a particular person encouraging them to keep their land healthy. Regarding your second question, our initiative looks at restoring land which includes increasing tree cover. Trees in this case, if indigenous to the particular region are viewed as good and beneficial not only for healthy soils and improvement of the agricultural production in the surrounding areas due to better water uptake but also for its climate smart properties in mitigating climate change. The only exception I would say that it is not beneficial would be if the trees were of an alien species- am I right? This brings me to my actual question for seeking this platform; our initiative is looking at ways to monitor restoration. I have very little experience in terms of restoration or monitoring. When do we say that restoration has occurred and how do we monitor this? Thank you for your assistance.
Comments 1 Votes 1 Like  Tags:none Answer/Comment
William Critchley, March 23, 2017 12:12 pm
Dear Zaka, Good to meet you and hear about your work. Excellent observations! The only thing I would add is that security of tenure is the key (not necessarily ownership), and with regard to the tree, yes, indigenous is good - but there are some 'friendly foreigners' such as Grevillea robusta from Australia which is very popular in East Africa. How do you monitor improvement in land degradation status? The white-coat boffins (lab scientists) would point to remote sensing methods (assessment of 'NVDA' i.e. vegetation cover over time) while others with dirtier boots may prefer to take plant counts and measure gully/ rill depth from small plots of land. Another supplementary method is simply to photograph a particular place regularly. I was involved in filming a particular site in Burkina Faso and another in Kenya 25 years ago: then I went back and filmed again....the result was a remarkable positive transformation. And the product (a film/ book module) I entitled 'More People, More Trees'. You can always try asking local people as well about changes as we did in the film. Probably its on YouTube? Finally, before I forget, for practical advice on methodology look up LADA (Land Degradation Assessment in Drylands) at Good luck! William Comment
Twebaze Jeniffer, March 23, 2017 1:32 am
I am Jeniffer from South Western Uganda, Kabale District. We are working with 4 farmer field schools in Kitumba sub County, Kariko village. We have introduced the send a rabbit micro project under the Fits Uganda community based organization. How can this micro project of small animals be well integrated in the sustainable land management the community is already engaged in.
Comments 7 Votes 1 Like  Tags:none Answer/Comment
William Critchley, March 23, 2017 6:18 am
Dear Jeniffer, Thank you for this question. A rabbit project sounds an interesting way to improve nutrition in a small scale way that is in reach of the poorest families. While I again request my fellow experts to help out here, what strikes me is that the rabbit droppings can be an excellent addition to compost heaps, thus improving soil fertility in the kitchen garden. And of course the rabbits can make use of all manner of green vegetation that otherwise would not be productive. So they can fit well within an overall 'SLM system' on the farm. I wonder if my colleagues have any experience of rabbits (or guinea pigs). Anyway, well done with the project and keep up the good work! William Comment
Twebaze Jeniffer, March 24, 2017 3:50 am
Thank you for your response. We shall use the droppings to enhance kitchen gardens and keep this platform updated.
William Critchley, March 25, 2017 3:47 am
Good to hear that Jeniffer. Please let us know if you or your group have any other questions. There is a full panel of experts here to help. Best wishes, William Comment
Twebaze Jeniffer, March 26, 2017 9:46 am
We are also planting sugarcane as a buffer on Lake Bunyonyi in the Kariko watershed
Is it a good practice in holding soil and lake siltation.
William Critchley, March 27, 2017 2:10 am
Dear Jeniffer - good to hear from you again and it's very sensible to protect the banks of water course/ water bodies with perennial, and productive vegetation. There's lots of erosion in that area and the sugar cane will help filter out the sediment before it reaches the lake. It will also benefit from the nutrient rich particles that have been eroded. Lake Bunyonyi (as many readers won't know is the deepest - or second deepest?) lake in Africa and in a beautiful location. My only word of caution would be make sure that when the sugar cane is harvested, don't burn it or there will be carbon losses and pollution. Jeniffer, do you and your colleagues plant contour barriers of vegetation in your sloping fields as well? Kind regards, William
Twebaze Jeniffer, March 27, 2017 2:21 am
Thank you Dr. William for your quick and useful responses. In the bigger watershed we are working in, agroforestry trees like Caliandra and gruveria are planted along the trenches. Elephant grass and other grasses too are planted to reduce runoff and to be used for animals on zero grazing and mulching.
William Critchley, March 27, 2017 10:39 am
It sound to me you are doing the right things - at least for your specific environmental situation (quite high altitude, reasonable rainfall, high population density and sloping lands). Keep up the good work! I can also now see more clearly where the rabbit project fits in!
Twebaze Jeniffer, March 23, 2017 1:32 am
I am Jeniffer from South Western Uganda, Kabale District. We are working with 4 farmer field schools in Kitumba sub County, Kariko village. We have introduced the send a rabbit micro project under the Fits Uganda community based organization. How can this micro project of small animals be well integrated in the sustainable land management the community is already engaged in.
Comments 0 Votes 1 Like  Tags:none Answer/Comment

No Answers Found

Farida Hassan, March 21, 2017 4:46 am
Along the coastal zone of Kenya people struggle to make a living from the sandy and infertile soil. Is there any advice about how the soil can be improved cheaply and easily to produce more nutritious crops?
Comments 7 Votes 1 Like  Tags:none Answer/Comment
William Critchley, March 21, 2017 9:44 am
Thank you very much Farida for this question, and knowing the Kenyan coast (and hinterland) quite well I understand your concern. While a common perception is one of lush greenery, in fact this is an area with very poor soils, erratic rainfall and poor yields. I shall call upon my other expert colleagues to answer in detail, but my feeling is that there is a strong role for leguminous agroforestry trees, with fodder strip connected to systems of zero-grazing of dairy cows. At least that should help with soil fertility (through N-fixation and manure produced) as well as nutrition (through milk from the cows). Other suggestions from my colleagues? Comment
Farida Hassan, March 21, 2017 10:11 am
Thanks William for the response,
This is highly appreciated....I did not anticipate such a quick feedback
Amy Bea, March 21, 2017 5:28 pm
Dear Farida, dear William,
William has answered Farida's question well. Thank you. My only addition is to also consider growing cover crops as green manure or leaving some residue on the fields after each harvesting - to gradually improve the soil quality.
William Critchley, March 22, 2017 3:59 am
Dear Amy, This is a useful addition to my answer. Thank you! Of course one of the problems we have always faced in much of Africa is livestock freely roaming - and then clearing the land of crop residues through grazing (actually this is sometimes a deliberate strategy in West Africa where agriculturalists want the dung from pastoralist's herds) but where we are talking about, as long as we can keep animals under control, (and I notice much more tethering of livestock than 20 years ago at the coast) then crop residues and green manures can indeed be helpful.
Farida Hassan, March 22, 2017 4:50 am
Thank you Amy, your comment is very useful
Martin Sishekanu, March 22, 2017 6:34 am
Dear Farida, William and Amy, Thanks for the reflections provided by William and Amy on this issue! It is true that dealing with sandy soils in production is not an easy issue but since we are dealing with farming for survival here solutions have to be sought. One biggest challenge with sandy soils is its poor state of soil structure and hence the inability for it to hold both plant nutrients and water against leaching. The need to enhance organic matter is therefore very critical in these soils. Once organic matter is improved even artificial fertilizer can economically be applied in crop production. In the Western Province of Zambia the Indigenous Community use in-situ soil fertility management for their Kalahari sandy soils whereby they construct temporal Cattle Kraals right in the field and allow animals to sleep in those night kraals for three to four days depending on whether in it during the rain or dry season respectively and move three sides of the kraal forward until the whole field is fertilised. In the past farmers would use tethering the animals on a pole each but now they generally used barbed wire. In this case urine goes into the soil whilst the Cow Dung remains on the soil surface as soil cover but eventually incorporated into the soil. Such a field would be used for three years before fertilisation is done in the same field. Households rotate in fertilizing their fields.
As William has indicated and if Zero grazing is used farmers could be encouraged to multiply the manure from the Zero grazing units. The Animal(s) would however, need some shelter for a better manure quality. This would involve cutting grass which is not useful to livestock and use it as mat of about 10cm thick on the floor of the Animal Shelter and allow the animal(s) sleep and deposit their urine and dung for a month and then come back and turn the mat upside-down and allow the animal(s) sleep over it again for one more month after which the manure is collected for further decomposition. Meanwhile another layer is added on the floor and a new cycle starts again as before throughout the year. The manure produced can be used directly in rip-lines or in basins under conservation agriculture systems.
One other aspect to consider is to examine the type of crops suitable for Sandy soils i.e. intensification of growing Cassava and Potatoes among others that do well under sandy conditions.
Farida Hassan, March 22, 2017 7:34 am
Dear Martin,

This is a comprehensive and robust response building on what William and Amy provided.
I must say I am very grateful for the technical input.
Kind regards,