Living Land

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trials give us hope for the intensification of agriculture in

desert sandy soils through organic and inorganic amend-

ments and boosting forage production.

Soil is made up of sand, silt and clay and has many thou-

sands of soil taxa, depending upon where you are on the

world soil globe. Plants and crops depend on soil for the

supply of water and nutrients, anchorage of plants and as a

medium in which to grow. Soil is a fundamental component

for food production and in providing other soil functions

such as climate regulation, nutrient cycling, habitat for

organisms, flood regulation, a source of pharmaceuticals

and genetic resources, foundations for human infrastruc-

ture, provision of construction materials, cultural heritage,

provision of food, fibre and fuel, carbon sequestration

and water purification and soil contamination reduction.

Thus we are justified in saying that soils deliver ecosystem

services that enable life on Earth.

Over many years humans have used soils to gain great

economic rewards. However, many of the methods used

to gain those benefits are now seen as unsustainable,

because in many cases they lead to degraded land. Hence

land degradation (loss or reduction of land functions or

land uses) becomes a serious worldwide environmental

problem, especially in the drylands that occupy one-third

of the Earth’s land surface. Land degradation is induced

through natural and human activities, and accelerated due

to persistent droughts in many developing arid countries.

Irrational use of soil resources has been carried out by

powerful competing economic and social forces that have

little knowledge about the potential of soil resources and

little or no regard for the long-term care of soils. Therefore,

there is a lot riding on our capacity to understand, conserve

and manage soil resources efficiently and sustainably. The

unsustainable use of soil resource is ultimately diminish-

ing its capacity for long-term services especially producing

food. Sustainable soil management could produce up to

58 per cent more food through agricultural intensification,

so that 95 per cent of our food is directly or indirectly

produced on our soils.

This provides hope for meeting the

future food demand of an increasing population.

Global data shows that 33 per cent of soils are degraded due

to diverse ailments. Among the natural forces of land degra-

dation, under desert conditions wind has a major role in soil

erosion. Globally over 24 billion tons of fertile soil was lost

due to erosion in 2011, that is 3.4 tons per person per year,

costing US$70 per inhabitant, or US$419 billion worldwide.

Without fertile soils, food security, poverty alleviation and

climate change mitigation and adaptation will not be achieved.

In addition to affecting agricultural farms through nutrient

mining, drifting soil also causes environmental issues.

Sandy soil amended for agriculture intensification

A field trial was conducted on sandy soil (

Typic torripsamment

) at an

ICBA station for barley forage production. Sandy soil is dominant in

the United Arab Emirates (UAE) and other Gulf Cooperation Council

countries and is used for agricultural and landscaping activities. The

sandy soil was amended with four inorganic amendments (AustraHort:

A1, Meliorit: A2, Zeoplant pellet: A3 and Zeoplant: A4) and one

organic amendment (Compost: A5) applied at the rates of 0, 1.5, 3

and 4.5 kg/m

. Standard fertilizer rates were used to offset nutrient

requirements of barley crop. Treatments were triplicated in Randomized

Complete Block Design. The plot size was 2.25 m

(1.5m x 1.5m).

Soil amendments can boost soil resource capacity, improving the

cost-effectiveness of agricultural production.

The standard agronomic parameters were recorded and biomass

determined. The trial was irrigated at two irrigation levels (75 per cent

ETc and 100 per cent ETc). The results have shown positive effects of

amendments addition to soil on biomass production. At both irrigation

levels the addition of amendments has shown promising results in terms

of fresh biomass increase (more than double) over control treatment. At

75 per cent ETc and 100 per cent ETc (control) biomass was recorded

as 6.5 and 9 tons/ha, whereas with the addition of amendments

variable increase of biomass was recorded, the maximum being 15.5

tons/ha with the application of 4.5kg/m

meliorit at 75 per cent ETc

(138 per cent increase) and 19.5 tons/ha with the application of

4.5 kg/m

zeoplant pellet at 100 per cent ETc (117 per cent increase).

This preliminary investigation provides hope for the intensification of

agriculture in sandy soils which are inherently low in crop productivity.

Source: ICBA

Amendment doses kg/m

1.5

4.5

Fresh biomass (tons/ha)

Water treatment 100% ETc

A2: Meliorit

A3: Zeoplant Pellet

A4: Zeoplant

A5: Compost

A1: AustraHort

Control

iving

and