Seedling emergence and growth responses of five desert species to sand burial depth The response on dark respiration of some tropical rain forest and coastal desert plant species to the elevation of CO 2 concentrations Photosynthetic characteristics of C4 desert species Haloxylon ammodendron and Calligonum mongolicum under different moisture conditions Characteristic in photosynthesis,transpiration and water use efficiency of Haloxylon ammodendron and Calligonum mongolicum of desert species