Successful Biological Methods for Combating Desertification at Degraded Areas of China - Combating Desertification in Asia, Africa and the Middle East - page 51

Tabl e 3. 1 Sowing rate of several main sand-holding species

Seed quantity

Seed quantity

per mu (kg a ) per mu (kg) a Species Species

Haloxylon ammodendron 1.5-2 Ta m a ri x spp. 0.5-0.7

Elaeagnus angustifolia 20-30 Calligonum spp. 10-12

Hedysarum scoparium 10-12 Nitraria tangutorum 10-12

Caragana korshinskii 13-15 Artemisia arenaria 0.5-1

a Note: 15 mu D 1ha

• Formalin: 12-20 days before sowing, spray the soil with Formalin solution (50 ml

Formalin

6-12 l water/m 2 ), then cover it with plastic film. One week before
sowing, uncover the film. The sowing can be done when there is no chemical
smell.

C

• Ferrous sulfate: applied in the form of water solution with the concentration of

2-3 %, 9 l/m 2 .

• Dikesong: The quantity and method of applying it are same as above.

• Also important treatments for different seeds, sowing period, sowing rate and

sowing methods are necessary.

The sowing rate for different plant species with seed quantity are recommended
by the scientists for planting of sandy lands of China (Table 3.1 ). The sowing rate
depends on whether the seed is planted in rows or is broadcast (hand spread) or used
in spot treatments.

2.1.4 Management During Seedling Stage

The management during the seedling stage, including soil management (fertilizer
application, irrigation, inter-cultivation and weeding), management and protection
of seedlings (thinning, shading, control pests and diseases and winter protection,
etc.), will begin after emergence and continue until transplanting. Irrigation, weed-
ing and thinning are necessary activities during the seedling stage.

• Species selection Natural conditions in various desert areas are quite different.

So, the selection of the species is the key of the successful artificial afforestation.
If the suitable species were not selected, not only will afforestation fail but there
would be waste of labor, material and money; also the potential of the land will
not realized due to the lack of trees on it. When selecting suitable species, the
following should be taken into consideration:

1. Select local sand fixing species which grow well;
2. Select the species with high economic value e.g. for construction materials, or
have fruits or nuts;

There are four main factors effecting the selection of desert plants: zonal,
temperature, ecological series and Sand dune sectors. There are a series of plant
species which are suitable for different desert types (Table 3.2 ).