The Alashan Desert is situated at the east edge of the Asian and African desert region, which is deep in the interior and less in precipitation. The long history of evolution makes desert plants to form the zonal vegetation, which is represented by the steppe desert and typical desert. 

According to research data, researchers summarized the content of the carbon (C), nitrogen (N) and phosphorus (P) in leaves of 54 desert plants, and revealed regularities and characteristics of the C, N and P in the desert plants in the Alashan Desert. 

C, N and P play an important role in plant growth and regulate various physiological functions. Leaf C, N and P stoichiometry varies with many aspects of plant biology. The ratios of C/N and C/P may reflect the balance between the plant demand and N and P availability and constrain various processes. Previous data from soils in China pointed to a shortage of P. Shortage of N was also reported from the Alashan Desert. 

Scientists from Cold and Arid Regions Environmental and Engineering Research Institute (CAREERI) therefore assumed that plant stoichiometry may reflect the low levels of N and P in the Alashan Desert soils. 

To find the ecological stoichiometry characteristics of C, N and P of the plants: perennial shrubs (PS), perennial herbs (PH) and annual herbs (AH). A total of 11, 13, 20 and 10 plants were sampled from PS, PP, PH and AH, respectively. The findings indicate that C, N, P in the plant leaves ranged from 236.48 to 513.54 (with an average of 379.01±55.42) mg/g for C, 1.2 mg/g to 37.37 (with an average of 10.65±7.91) mg/g for N, and 0.11 mg/g to 4.5 (with an average of 1.04±0.81) mg/g for P. Whereas C and P, and N and P were positively correlated in agreement with previous publications, no significant relation was found between C and N, in disagreement with previous publications. 

As for N and P, these values were substantially lower for PS. The average values for PH and AH were 11.55(±7.34) and 10.88 (±7.17), mg/g for N, and 1.47 (±0.94), and 1.41 (±0.94) mg/g for P. As for PS, they were 10.38 (±8.24) and 0.84 (±0.65) mg/g for N and P, respectively. The average values found for N and P in the Alashan Desert were substantially lower than the typical values reported form other desert regions in China having on average 24.4 (±8.10) and 1.74 (±0.88)mg/g of N and P, respectively.  

Furthermore, out of all plants examined, 71% of the plants had a ratio of N/P＜14 which implies that plant growth is primary limited by N. Interestingly, the lowest values were found in leaves at the new shoots and researchers presume that nutrients are transferred from leaves at the older branches to leaves at the younger shoots. Data thus imply that the Alashan desert plants are adapted to substantially low values of N, and also, following the low ratio of N/P, to low amounts of P. Currently, lab experiments are taking place in order to assess the extent to which the Alashan desert plants are adapted to low values of N and P. 

This research is financially supported by the National Nature Science Foundation of China (No. 41101054) and the Strategic Leading Science and Technology Projects of CAS (No. XDA05050406). This paper has been published in the Acta Ecologica Sinica.