This article was downloaded by: [The Aga Khan University]On: 08 October 2014, At: 03:13Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number:1072954 Registered office: Mortimer House, 37-41 Mortimer Street,London W1T 3JH, UK

Arid Soil Research andRehabilitationPublication details, including instructions forauthors and subscription information:http://www.tandfonline.com/loi/uasr19

Dryland Restoration andRehabilitationJames Aronson , Shivcharn Dhillion & EdouardLe Floc'HPublished online: 30 Nov 2010.

To cite this article: James Aronson , Shivcharn Dhillion & Edouard LeFloc'H (1999) Dryland Restoration and Rehabilitation, Arid Soil Research andRehabilitation, 13:4, 315-317, DOI: 10.1080/089030699263203

To link to this article: http://dx.doi.org/10.1080/089030699263203

PLEASE SCROLL DOWN FOR ARTICLE

Taylor & Francis makes every effort to ensure the accuracy of allthe information (the “Content”) contained in the publications on ourplatform. However, Taylor & Francis, our agents, and our licensorsmake no representations or warranties whatsoever as to the accuracy,completeness, or suitability for any purpose of the Content. Anyopinions and views expressed in this publication are the opinions andviews of the authors, and are not the views of or endorsed by Taylor& Francis. The accuracy of the Content should not be relied upon andshould be independently verified with primary sources of information.Taylor and Francis shall not be liable for any losses, actions, claims,proceedings, demands, costs, expenses, damages, and other liabilitieswhatsoever or howsoever caused arising directly or indirectly inconnection with, in relation to or arising out of the use of the Content.

This article may be used for research, teaching, and private studypurposes. Any substantial or systematic reproduction, redistribution,reselling, loan, sub-licensing, systematic supply, or distribution in anyform to anyone is expressly forbidden. Terms & Conditions of access

and use can be found at http://www.tandfonline.com/page/terms-and-conditions

Dow

nloa

ded

by [

The

Aga

Kha

n U

nive

rsity

] at

03:

13 0

8 O

ctob

er 2

014

Round Table

Dryland Restoration and Rehabilitation

Guest Editors :

JAM ES ARONSON

Centre d’Ecologie Fonctionelle et Evolutive (CNRS UPR 9056)Montpellier, France

SHIVCHARN DHILLION

Department of Biology and Nature ConservationAgricultural University of NorwayAas, Norway

EDOUARD LE FLOC’H

Centre d’Ecologie Fonctionelle et Evolutive (CNRS UPR 9056)Montpellier, France

In November 1994, 125 people from 31 countries and 5 continents gathered on thearid island of Djerba in southern Tunisia to discuss and debate restoration andrehabilitation practices in arid and semiarid lands. The papers presented dealt pri±marily with agricultural landscapes and/or rangelands in the African drylands northor south of the Sahara but also included contributions from southern Europe, SouthAmerica, and western Australia. Most of the papers presented were published inFrench (Pontanier et al., 1995), but six papers covering a cross section of the sympo±

sium and deemed of broad international interest were selected for submission toArid Soil Research and Rehabilitation. All were reviewed and revised and are com±

pletely independent of what was published in the proceedings.The papers brought together here include two rather general ones, dealing with

soil degradation and the use of annual legumes, respectively. One of the most suc±

cessful of traditional farming techniques employed in dry tropical West Africa isportrayed, including techniques to ‘‘harness’’ termites to the tedious task of breakingup impermeable soil crusts. Mediterranean climate drylands are well represented bytwo examples± one in Tunisia and one in central Chile± of long± term R&D projectson the rehabilitation of entire agropastoral ecosystems, including of course, theirsoils. Finally, a broad socioeconomic analysis is provided as well.

More speci�cally, Bridges and Oldeman give an overview of soil degradation inthe arid zones of the world, employing a novel perspective on soils as a naturalresource that should be managed through international cooperation. An example

We would like to thank the contributors who patiently awaited the late arrivals . Edie Allen and BillNiering provided helpful comments on several of the manuscripts.

Address correspondence to Dr. James Aronson, CEFE/CNRS, F ± 34293 M ontpellier Cedex 5,France. E± mail : aronson@ cefe.cnrs.mop.fr

Arid Soil Research and Rehabilitation, 13 :315­ 317, 1999Copyright 1999 Taylor & FrancisÓ

0890 ± 3069/99 $12.00 1 .00 315

Dow

nloa

ded

by [

The

Aga

Kha

n U

nive

rsity

] at

03:

13 0

8 O

ctob

er 2

014

316 J . Aronson et al.

from North Africa is provided. Next, Mike Ewing provides a broad overview of theuse of annual legumes, one of the leading bio± tools for arid soil rehabilitation inlow ± rainfall, Mediterranean± type climate rangelands in North Africa and the NearEast. Where direct evidence is not available from these areas, his analysis relies onanalogies with managed systems in western Australia, where by far the most experi±ence exists to date with these kinds of systems.

Roose et al. describe the Za õÈ system, a traditional West African system whereincertain species of termites and the concentration of surface runoV , manure, andmineral nutrients into microcatchments or microwatersheds are used to amelioratesoil surface conditions and improve water in�ltration. Impact is reported in terms ofincreased sorghum productivity and also on plant species richness among herbs andshrubs.

Coming back to the Mediterranean area, Le Floc’h et al. describe a long± termeVort in southern Tunisia aimed at reconstituting a simpli�ed, low± stature version ofa preexisting ‘‘ecosystem of reference’’, which not only can support increased grazingby domestic livestock, but also can provide a framework (or biological ‘‘matrix’’) forthe subsequent reintroduction of the indigenous tree stratum long since removed byexcessive wood cutting.

Like the Tunisia project, experimental plant introductions were also used in theproject described in the paper by Ovalle et al., which provides a 10 ± year progressreport for a rehabilitation project in central Chile. Here the profoundly degradedsoils of the unirrigated portions of the Central Valley are being experimentallyrehabilitated through the modi�cation of current land and tree management prac±

tices and through the introduction of various woody and annual N ± �xing legumesof multipurpose or pastoral value. Both native and nonnative species are being used,but of particular interest, apart from the dramatic impact of the legumes, is thebroad landscape­ scale perspective adopted.

Last, Chassany provides a personal appraisal of the economic and social con±

siderations required to make a holistic evaluation of restoration, rehabilitation , andreallocation at the landscape level (Aronson et al., 1993). As was frequently recalledat the conference in Tunisia, and as all readers are well aware, socioeconomic con±

straints and considerations often represent the crucial linchpin determining successor failure, not to mention the mere feasibility of starting up a restoration or rehabili±tation project of any importance in arid and semiarid lands.

Translations, reviews, and revisions were rather long in coming, but the collec±

tion of papers still has much interest in our view. This is particularly so as regardsthe confrontation of ideas and techniques concerned primarily with rehabilitationversus those concerned more with restoration sensu stricto.

As Le Floc’h et al. write, ‘‘The main objective of ecological rehabilitation is topilot trajectories of disturbed ecosystems so that they may recover their main func±

tions, including productivity, via intensive interventions of relatively short duration.Rehabilitated ecosystems should become autonomous and have sufficient resilienceto recover after moderate disturbances.’’ Thereafter, it is possible to proceed towardfull restoration or else ‘‘pilot’’ the systems in question in other directions accordingto local needs and priorities and, of course, the potentialities of local climate andsoils. But until that �rst level of reparation is achieved, nothing else, long± term, isrealistically possible. This in a nutshell is the current situation of almost all thepopulous dryland regions in the world today. As Ewing says in his paper, ‘‘. . . arewe concerned exclusively with the 1000 ha that might be fully restored or, rather,with those as well as the 100 million that might be rehabilitated today ?’’

Dow

nloa

ded

by [

The

Aga

Kha

n U

nive

rsity

] at

03:

13 0

8 O

ctob

er 2

014

Dryland Restoration and Rehabilitation 317

References

Aronson, J., C. Floret, E. Le Floc’h, C. Ovalle, and R. Pontanier. 1993. Restoration andrehabilitation of degraded ecosystems. A view from the South. Restoration Ecology 1 :8­17.

Pontanier, R., R. M’Hiri, N. Akrimi, J. Aronson, and E. Le Floc’h, eds. 1995. L’Homme peut± ilrefaire ce qu’il a John Libby Eurotext, Paris.de fait ?

Dow

nloa

ded

by [

The

Aga

Kha

n U

nive

rsity

] at

03:

13 0

8 O

ctob

er 2

014