Living Land

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Biosaline agriculture as an approach

for combating desertification

Dr Abdullah Dakheel, Dr Rao Nanduri and Dr Richard Soppe, International Center for Biosaline Agriculture, Dubai

esertification has several causes, including popu-

lation pressure, changing climatic conditions,

economic, political and social conditions, and lack

of access to science and technology.

The Millennium Ecosystem Assessment lists overgrazing as one

aspect of the desertification cycle, when land and water do not

provide enough resources for sustainable grazing. Salinization

of soils is another chain in the process towards desertifica-

tion. Desertification usually results in more poverty which

in turn strengthens the conditions leading to desertification.

Rehabilitation of desert systems requires the adoption of multi-

ple strategies including the rehabilitation of natural degraded

ecosystems and the use of the limited water resources in agri-

culture production, afforestation and aquaculture systems in

certain cases. However, water resources in deserts are in most

cases limited to groundwater of ancient origin or shallow aqui-

fers that mostly have became salinized due to overutilization

and depletion. In coastal and subcoastal deserts seawater and

highly salinized groundwater resources exist in large quantities;

however their use in rehabilitation requires the use of special

agroecosystems that can tolerate such high levels of salinity.

An approach to break this cycle is through the application

of biosaline agriculture at different locations in the land-

scape. More salt-tolerant and drought-tolerant plants can be

introduced, allowing the use of marginal water resources to

increase plant production for foraging or fodder, thus reduc-

ing the risk of overgrazing. Higher-value salt-tolerant plants

and trees can be introduced to provide a source of income

to local populations. In addition to introducing landscape

management, socioeconomic and (implementation of) policy

decisions are needed. The introduction of managed forage

land under saline conditions, for example, should not result

in an increase of the grazing population larger than the carry-

ing capacity of the managed lands.

Several aspects need to be considered when biosaline agri-

culture is introduced. Introducing new genetic resources (new

genotypes or more salt-tolerant species) requires access to

seeds, or introducing nurseries, as well as an assessment of

crop diversity and management to maintain the local diversity

(prevent invasive species to compete out the local genotypes

and varieties, for example as is the case with wild melon in

Australia). Maintaining the local biodiversity ensures an ecosys-

tem that is adaptable to changing environmental conditions.

Image: ICBA

Rehabilitation of desert areas with salt-tolerant grasses (Oman)

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