Manipulation of Vegetation Communities on the Abu Dhabi Rangelands, Essay Example

With the aim of resuscitating fields of grasslands the United Arab Emirates measures were put in place to ensure an increased cover of different grass species. This was carried out in the Baynunah ranges of the Abu Dhabi emirate. The measures taken include releasing certain rangelands from the prolonged grazing by the camels and goats and also initiating sprinkling irrigation on some of the fields. Different grasses responded differently to the measures initiated thereby giving different observable results.

Grazing on the vegetation fields had, at one point, been limited in the Middle East as a result of unavailability of sufficient water sources for livestock keeping purposes and the general case of political instability in the region. When oil was discovered in many countries of the gulf region, and with the subsequent attainment of political stability in the region, cash-flow increased among the region’s inhabitants. Increased cash flow resulted into increased availability of facilities that could be used for livestock rearing on the ranges. As many people bought these facilities and ventured into the livestock keeping activities, the pressure on the vegetation fields as a result of grazing increased to a point where it threatened to totally wipe out some grass species.

The study was carried out in two major areas:

• An area in Baynunah ranges that had been protected from animal grazing for over eleven years. It had been closed after prolonged grazing by goats and camels. Its response as a result of the release from grazing was studied. This piece was referred to as enclosure.
• Another area, also in Baynunah ranges was a rangeland that had been protected from grazing for over eight years. This land had been irrigated in the months of summer, spring and autumn over this period using sprinkle irrigation. The response of this grassland was studied to give a projection of how irrigation impacted on the grass population.

The study was based on six categories as a result of two types of substrata for it had been noticed that the two substrata layers (gravel plain and sand dune) showed support to different species of grass communities. The categories that were used are:

• Gravel plain Non-grazed Non-irrigated (GNN)
• Gravel plain Non-grazed Irrigated (GNI)
• Gravel plain Grazed Non-irrigated (GGN)
• Sand dune Non-grazed Non-irrigated (SNN)
• Sand dune Non-grazed Irrigated (SNI)
• Sand dune Grazed Non-irrigated (SGN)

Results and observations

It was found that the richness of grass species was greater in the enclosure. But this richness was only on those that grew on the sand dune substratum. Irrigation on the other hand had a little impact on the richness of the grass species on both the two strata. The perennial percentage, however, increased on both of the substrata.

Other observations made were:

• Irrigation resulted into the fall of soil pH in the sand substratum but an increase in the pH in the gravel substratum.
• Soil conductivity rose with irrigation in the sand substrata.
• Gravel content decreased in the upper profile of the soil in gravel dominated areas.

Discussion

Prolonged and heavy grazing on a given piece of land results in the existence of specific grass strands that are able to withstand pressure as a result of overgrazing.

Little change in richness of the grass species after irrigation suggests that irrigation or the lack of it does not necessarily support the increase or decrease of a given species of grass in area.