Special Organic Fertilizer for Improving Soil Fertilization and Xerophyte Haloxylon ammodendron Growth in the Nursery and Afforestation in Desert Regions of China

The aim of the study was to investigate the effects of a special organic fertilizer (SOF, with common organic fertilizer (COF) as the carrier and Na+ as well) on the growth performance of Haloxylon ammodendron, and soil properties in desert regions of China. All fertilization treatments were applied to seedlings in the nursery in open field in Alashan Right Banner (ARB, severe arid area) and Hangjin Banner (HB, mild arid area) of Inner Mongolia (plants were not used for afforestation), and unfertilized 1-year-old plants cultivated in Minqin (MQ, moderate arid area) of Gansu province were selected and applied SOF for afforestation in ARB, HB, and MQ, respectively. The results (take ARB for example) indicated that SOF significantly increased plant height (PH) by 52.2 and 37.6%, main root length (MRL) by 42.6 and 22.8%, and dry weight (DW) of whole plant by 142.4 and 104.6%, respectively, over the CK and COF treatments in the nursery. SOF also significantly mitigated deleterious impacts of drought stress on the growth of H. ammodendron and enhanced soil properties in afforestation, where it increased survival rate (SR) by 50.6% and 28.9%, PH by 17.2% and 12.1%, MRL by 43.5% and 44.8%, and DW by 110.3% and 54.7%, respectively, compared with CK and COF treatments. Furthermore, soil organic matter (SOM) in SOF treatment was significantly increased by 210 and 6%, and no significant effect on Na+ content in root zone soil was observed in afforestation. The effects of SOF on H. ammodendron and soil properties were more remarkable in MQ and HB than in ARB. We conclude that SOF provide efficient nutrients for H. ammodendron, and the Na+ released by SOF can be utilized by H. ammodendron in time, and will not be released to soil in large quantities, which initiates a new method to restore degraded vegetations in desert regions of China.