Egypt, the country with 7,000-year-old record of civilization, has a unique situation in the world due its arid climate, limited arable land (3.6% of the total land’s area, which is over 1 million km²) and limited water resources that is mainly based on only one source ”The Nile” (the country has a yearly fixed water share of Nile water amounting 55.5 109 m3). The population is increasing reaching currently over 90 million. The large population produce a huge amount of sewage water. Unused sewage water is a hazard for human health and the environment and at the same time a waste of nutrients, water and energy sources. In the mid 90s, the “National Programme for the Safe Use of Treated Sewage Water for Afforestation” was launched. Within the frame of this programme, a pilot project was conducted to determine the success/failure of afforestation using basic-treated sewage water. Over 4,000 hectares of plantation forests spread over the desert lands of the county were established. The outcomes of this pilot project was very promising,

1) confirming that sewage water can be used for the establishment of new forest plantations, and

2) showing high potential for afforestation of multipurpose species of socio-economic importance in the desert lands of the country.

Beside this high potential, Egypt offers a great opportunity for large-scale afforestation due to the availability of huge volume of sewage water and large area of unused desert-lands. However, Egypt lacks experience in the forest sector. The development of sustainable forestry in arid regions must be based on scientific knowledge. An Egyptian-German team of scientists was, therefore, formed to support the establishment of plantation forests and the development of sustainable forestry in desert lands of Egypt using sewage water.

Modern silviculture, as a management system of forests, is based on the integration of the ecological, technological, and demographic realities associated with the economic aspects to achieve optimal solutions. There is no only one system to be practiced but many, which depend on the actuality and the desired objectives of establishing new forest plantations. The objectives can vary from environmental motivation, carbon sequestration, protective to productive purposes, whether e.g. for production of timber, biomass or biofuel crops.
The approach is to develop a decision support system for the sustainable management of plantation forests in arid regions. This will endorse the involvement of national and international organisations towards large-scale afforestation over the desert land of the country using sewage water.
The development of such a system requires scientific knowledge based on long-term observations. In 2012, the German-Egyptian team started a project supported by the German Academic Exchange Service (DAAD). Different experiments were installed for comprehensive observation to support the realisation of the project objective in developing a decision support system. Information to support the development of the management system will be mainly gained from: long-term observations of different field experiments installed in new established plantations, data and results of the pilot project, assessment of the sewage water situation, acquired ecological and socio-economical information, and the knowledge of the involved working group.

The field work is grouped in field activities and experiments. Researches are only conducted in the field experiments, while the field activities serve the afforestation.

Field activities and experiments within the frame of the project and their size per location in feddan (1 feddan = 4,200 m² = 0.42 ha)

The plots of the experiments are permanently installed. The experiment plots services as units for education, training, and demonstration. A comprehensive long-term observation of eight to ten years is foreseen.

Experiment I deals with investigations on the effect of irrigation water quantities (Experiment Ia and Ib) and irrigation systems (Experiment Ib) on survival and growth of selected species at two locations: Ismailia and Luxor. The selected species is classified into groups of four species according to their similarity in water consumption. In Experiment Ia, each set of species received, according to their average water consumption, five levels of irrigation water quantity with an equidistant difference pattern. In Experiment Ib, only three selected species are studied (Gmelina arborea, Khaya senegalensis, Tectona grandis), for which three levels of irrigation water quantity with an equidistant difference pattern are investigated for four different irrigation systems. The scheme of separating Experiment I in two studies is favourable, as it keeps the number of the experimental units small and the material cost low and, thus, optimises the cost-benefit relationships of the investigations. Results of Experiment I will help identifying the proper irrigation system, and the most favourable level of water quantity for each species under different environmental conditions.

Experiment II will make use of the outcomes of Experiment I. For each species, the appropriate irrigation system, and water quantity will be used to serve the appropriate implementation of the afforestation on larger area in Experiment II. Large area is necessary for long-term observations until harvest. As Experiment I is conducted earlier, results of the most favourable water quantity for a species and site at different plant ages will be used to irrigate the plantations in Experiment II. This scheme will be valid as long as Experiment I under observations. Nonetheless, the proper irrigation system will only be once identified according to the first-year results of Experiment I. However, information on the effect of the different irrigation systems during the rotation period of a species will be further gained over the foreseen observation period of Experiment I. This is planned to be four or five years, depending on species, as over this period no competition between plants is expected to affect the collected data. In addition, over this period most relevant data to crop water consumptions will be collected. In Experiment II, different techniques aiming at improving quality, yield and the economic value of the plantations will be employed. For each species, different spacing patterns and silvicultural techniques, which include thinning, pruning, and improvement of potential crop trees, will be practiced.As the choice of inappropriate techniques can considerably reduce quality, yield, and economic values, the outcomes of Experiment II is so imperative to identify the most effective silvicultural practice for each species depending on the desired objective of the afforestation. Moreover, in Experiment II, observation of the plantations and annual foliage analysis will be frequently made over the rotation period of each species to identify possible nutrient deficiencies and permit immediate application of effective fertiliser.

Experiment III is conducted to test the effect of soil improvement techniques (mycorrhiza and soil conditioner) on germination (Experiment IIIc) and survival and growth (Experiment IIIa and Experiment IIIb) of the different species used in the afforestation. Yet, Egypt lacks experienced forest engineers that can properly manage the afforestation in the many different locations of the afforestation areas in the country. The objective of this study is to generalise an efficient management option, which can be practiced for the different locations of the afforestation. Experiment III contains three studies: Experiment IIIa, IIIb and IIIc. Experiment IIIa and Experiment IIIb deal with the impact of soil improvement techniques (mycorrhiza and soil conditioner added to seedlings at the planting time in the field) on seedlings. Experiment IIIa involves all species employed at the first phase of the afforestation, while Experiment IIIb studies few species (Gmelina arborea, Khaya senegalensis, Tectona grandis) in more details using different water quantity. Experiment IIIc investigates the effect of soil improvement techniques on seedlings breeding in nurseries.

Experiment IV deals with assessment of the potential of the different existing plantation forests.

Hany El Kateb, Institute of Silviculture, Technische Universität München