Living Land

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(

Portulaca oleracea

), jute mallow (

Corchorus olitorius

), rocket

(

Eruca sativa

and

Diplotaxis tenuifolia

), safflower (

Carthamus

tinctorius

) and wild drumstick tree (

Moringa peregrina

) have

considerable value in terms of their tolerance to salinity and

harsh climatic conditions. Many such species have the potential

for more widespread use and their promotion could contrib-

ute to food security, agricultural diversification and income

generation, particularly in areas where cultivation of major

crops is constrained or economically unviable. Similarly, salt-

and drought-tolerant non-native species such as leaf mustard

(

Brassica juncea

), quinoa (

Chenopodium quinoa

), salicornia

(

Salicornia bigelovii

), guar (

Cyamposis tetragonoloba

) and

amaranth (

Amaranthus cruentus

) which showed good adapta-

tion in field trials under harsh conditions in the UAE, are likely

to be of value in providing cost-effective and long-term solu-

tions to problems of water shortage and increasing salinity of

soil and water resources in the region. Besides their tolerance to

abiotic stresses, all these species are nutritionally rich and can

thus play a crucial role in combating vitamin and micronutrient

deficiencies frequently experienced by inhabitants of marginal

environments. Research to improve the productivity and value

of these crops, and to encourage them to be more widely

cultivated, would contribute to food, income and nutritional

security for smallholder farmers in marginal environments.

Medicinal crop production systems

In combating desertification, integration of biodiversity conser-

vation into economic development — accomplished through

sustainable production and commercialization of natural prod-

ucts derived from native plants — is beginning to emerge as a

major strategy in several countries. Deserts harbour a variety

of flora adapted to the dry conditions and surviving for several

years without water. The medicinal value of these plants is well

known, for example, nearly 20 per cent of the 750 native plant

species documented in the UAE are known to have medicinal

properties. Two good example are

Aloe vera

(sabar), a shrubby

xerophytic, succulent plant used for centuries for its health,

beauty, medicinal and skincare properties, and

Cynomorium

coccineum

(tarthuth) a parasitic plant considered as a ‘treasure

of drugs’ because of its numerous traditional therapeutic uses

in treating colic and stomach ulcers, piles, nosebleeds, dysfunc-

tional uterine bleeding and as a contraceptive. Most medicinal

plants are still being collected from the wild population and

many are being seriously threatened by overgrazing and habitat

degradation. According to the UAE Red Data plant list, of the 132

species of medicinal plants, six species fell under the threatened

category. Thus, it is important to integrate commercial exploita-

tion with action plans for sustainable conservation and use.

Seawater and brine-based systems

To provide additional income and reduce the poverty cycle,

improving water supply for human consumption and irrigation

purposes requires the desalination of groundwater. Approximately

15 per cent of farmers in the Arabian Peninsula have installed

small-scale reverse osmosis (RO) plants to desalinate the ground-

water for field crop irrigation. These RO plants produce highly

concentrated brine which can be used as a resource under best

management practices. A project to showcase the potential of a

farming system using seawater-level brine was developed in the

UAE. The desalinated water is used to irrigate a large variety

of high-value vegetable crops (such as asparagus, eggplant and

radish). The produced brine is used for aquaculture, followed by

irrigation of salt-tolerant forages and halophytic plants. The mari-

culture system contains fish, sedimentation and seaweed tanks.

Two fish species (sobaity seabream and tilapia) showed adapt-

ability to the fish tank conditions in the Emirati climate. One of

the halophytic species irrigated with brine is

Salicornia bigelovii

a multipurpose species that can be used as a vegetable, biofuel

or fodder. Previous research found that cultivating the proper

salicornia varieties, combined with suitable agronomic practices,

could be economically viable and successful in marginal land.

Production systems based on treated wastewater

Arab countries are expected to face severe water scarcity as early

as 2015, when the annual per capita water share in the region

will fall to less than 500 m

. Give that agriculture uses 70-80

per cent of all water, the reuse of reclaimed (treated) wastewa-

ter for irrigation could contribute considerably to the reduction

of water scarcity for domestic use. In many countries of the

Arabian Peninsula, due to the problem of social acceptance and

the perception of health risks, municipal wastewater, even after

tertiary-level treatment, is not used for growing food and feed

crops. In the UAE, of the 600 MCM of tertiary-treated wastewa-

ter produced per year, 58 per cent (352 MCM) is used mainly

for landscaping and the rest is discharged into the sea. In fact,

reclaimed wastewater can be a valuable resource to grow bioen-

ergy crops for the specific purpose of producing liquid fuels, with

considerable economic and environmental benefits, when social

barriers prevent its use for growing edible crops. If bioenergy

crops can be cultivated on a commercial scale, they can reduce

pressure on fossil fuels while simultaneously improving environ-

mental quality and reducing desertification/soil erosion which is

also a matter of serious concern in the region.

Salt-tolerant and drought-tolerant plants allow the use of marginal water

resources to increase plant production and reduce overgrazing

Image: ICBA

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