Wealthy Gulf Arab companies are boosting their investment in Africa’s vast lands and untapped resources, marking a shift for investors who have traditionally directed their money towards assets in the United States and Europe.

One reason for the shift is negative: with government debt problems weighing on US and European markets, those regions no longer look as attractive to some Gulf investors as they did a few years ago.

But there are also a string of positive motives, including Africa’s fast economic growth, the rise of a free-spending African middle class, and a sense that much of the continent is becoming better governed and more stable politically.

Also, Africa has two special attractions for the arid desert countries of the Gulf: it is a source of food and arable land, and it is launching an infrastructure building boom that recalls the Gulf ’s own construction spree in the past decade. The Gulf ’s expertise in developing airports, ports and communications networks at breakneck speed can be used in Africa.

The result, corporate executives say, is a flow of Gulf money into Africa that has accelerated over the past year, and which could become an important contributor to growth on the continent.