A way through of the current conundrum Fuel or Food could be Agroforestry, I wonder what nobody is real looking into it, at least so far.

Modelling of Biofuel system is the way to evaluate them, however flexible tools are still not in place.

An integrated environment which is able to model, arable, grass and woodland systems alike and their mix, descrying C cycle (including Soil C at different scale of details) will be the ideal.

Also such environment should be linked to LCA tools, to assess over cost benefits in term of inputs sources.

Dear Emiliano,

I suspect that you are misconsidering an important factor.

As crops, bioenergy crops are very sensible to the quality of the site, so that one can expect a significative reduce of yields in marginal lands. That in terms give a very bad balance cost/benefits that might limitate its implementation.

Kind regards

Have you read this?: http://bioenergycrops.com/7-alternatives-as-energy-crops-for-marginal-lands-with-enough-scientific-evidence/

Emission savings from a perennial is the most efficient bioenergy we know until today. In particular when land use promoto a rotation of it and when nutrient extractions are considered in a holisic management as Allan Savory would say (a nice video of him can be watch here: http://www.youtube.com/watch?v=vpTHi7O66pI ). Greener areas, bioenergy from perennial, a more sustainable land use complementing food production areas in semiarid lands and reforestation patterns are all possible. Marginal areas have low productivity but 5-10 dry matter tons per ha per year are possible in many of them as you can read in the post mentioned above.

I do agree in that the use of marginal land do not compete directly with food production, and it can be fairly productive. However, I do think that the concept of CROP is not the right one. They would have lower energy and economical balances, and would produce significaitive environmentla impacts, related to soil disruption-erotion and seriosly affecting biodiversity, which tend to remain in marginal lands. I would go for biomass extraction instead of cropping. Regarding the nutrient cycling, Pyrolisis is an annefficient process, regarding both: loss and denature (biologization/mineralization) of nutrients. Biogas production is considerably more efficient in both terms.

Thanks Alfredo. But the problem is all about information and some misconceptions on scientific methods to determine what is economically, environmentally and energetically sustainable and what is not.

Perennial species promotion could:

* increase biodiversity. Monoculture takes place in most arable lands and rural areas, in particular in semiarid lands or constraint environments. This is because low productivity is linked to many limitations in market and farmers activities have scarce oppportunities to progress or determine a single option or product. Sinergies between bioenergy and agriculture or livestock can determine many alternatives and promote a lot of crops. See our website (www.bioenergycrops.com) just to see some examples. Additionally you might consider agroforestry alternatives (more than one product per hectare) with a huge potential with bioenergy and fuelwood both in developed and developing countries.

Most studies had suggested that 1st generation biofuels and annual crops could contribute to endanger biodiversity. But that was 10 years ago. Trends and policies now show that perennials, forestry and lignocellulosic crops can promote a more biodiverse environment in rural sectors as well as a greener world. Good articles you can read are the following:

a) Biofuels and Biodiversity, Wildlife Habitat Restoration (2013). http://bit.ly/XIn1aK

b) The current bioenergy production potential of semi-arid and arid regions in sub-Saharan Africa (2012). http://bit.ly/10FLfkX

c) The role of bioenergy in a fully sustainable global energy system (2012). http://bit.ly/GS51Pp

d) Is energy cropping in Europe compatible with biodiversity? – Opportunities and threats to biodiversity from land-based production of biomass for bioenergy purposes (2012). http://bit.ly/YrLfSl

* Erosion control is often not possible to be controlled. Most agricultural operations and trends are promoting ploughing or harrowing instead of short rotation forestry and perennial species as we were mentioning before. Good evidences on this were studied in many large reviews of highly reputed peer-reviews scienfic journals like this one among many others: http://bit.ly/12P8RZH

* Impacts of annual crops and monocultures can be diminished clearly in most lands with low productivity. Here some evidences: http://bit.ly/10FJCE3

* Biomass extractions and residues are finite. This is clearly studied by many environmental and governmental organizations like European Environmental organization here: http://bit.ly/ZztSQx

Ok Emiliano,

I get your point. You are right in most of it. Nevertheless a warning must be taken.

CHANCES are wide and broad. Potential are infinite. But no resourses are realy left over by man or nature, even if they are marginal. As a scientist (ecology-Agronomy) I can imagine a system that increase biodiversity through management, deppending on what parameters are messured. But as a man with concrete rural experience I can see that reality is very different from theoretical posibilities. To intervine and suppress a naturalized ecosystem rarely improves biodiversity.

Certainly erosion can be control, highly when marginal lands are not plowed, that is the value of perennial plants, in my opinion.

Perhaps I missanderstand your concept of marginal lands, but I do know that today bioenergy is pressing many "non"productive lands, as wetlands, savanas, and others. We need to take into consideration the environmental services that we will loose when drifting to bioenergy. The balaces might be good or bad depending on the site.

Saludos!

You're 100% right. We need to know and considerate potential impacts. The questions I ask always are these:

* Are we taking into consideration carbon, gas, oil or nuclear energy impacts and costs? Risk management is not always considered when calculating services (see Fukushima costs as a clear example of what people be willing to accept and even to pay if a risk prime would be there when nuclear energy is in the governmental planing).

* Are arable lands used sustainably today for food? Which are their inputs?

* If a farmer or land will provide energy or avoid emissions, do we have to compare with food production emissions too? And what about those producing both things (energy and food) as it is happening in many areas of the world? What about producing food, paper and energy? and so on....

What I feel is that there is a clear evidence that wheat and corn ethanol, as well as some crops for biodiesel, are not feasible in marginal lands. Nevertheless, most evidences show that perennials and forestry could promote employment, avoid emissions and create biodiversity and reduce risks for many in the world.

Ok Emiliano, we agree. Forestry is even more interesting, as rotation time ar far longer (therefore they do become biodiversity habitat), and the energy balances are more positive.

Maik, thanks for the link, I pretty much like the approach of your statement. I cannot find your subject in the link. Can you please specify it?

Best regards,

Alfredo

Alfredo, the rate of C absortion and productivity changes depending on rotation to be shorter. A mature forest absorb with lower rates comapred to a rapid growth forest that is cutted every 3 years (not in all situations of course). Grasses capture higher rates many times depending on sites and species (in particular C4 grasses have really high rates too). If you cut them every year, or even twice a year, they absorb a lot. If you replace coal or natural gas, you have a net benefit to the carbon cycle, to soil erosion, to bioiversity and subsequent cereal yields if their were cultivated in agricultral arable lands (using rotations).

Hi Maik,

Impresive amount of subjects!

All the best,

Alfredo

http://bioenergycrops.com/blog/2013/05/29/bioenergy-crops-in-marginal-lands-lower-yields-can-have-lower-costs/

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