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Land degradation and desertification are the serious ecological problems and challenges to achieve global sustainable development goals. The Chinese government proposes to integrate the construction of the Silk Road Economic Belt with the environmental improvement of the Central Asia, to build an intimate community of shared destiny between China and the Central Asia countries, and to promote the green and sustainable development of the Silk Road Economic Belt. However, the ecological crisis in the Aral Sea causes a significant shrinking in water body, loss of biodiversity, salinization, desertification, and salt dust storm, which have become major environmental problems encountered in the construction of the Silk Road Economic Belt in the Central Asia. On the basis of sorting out the problems of land degradation and desertification caused by the ecological crisis in the Aral Sea, this study scientifically analyzed the development trend and causes of desertification and salinization land in the Aral Sea region in the past 30 years, discussed the spatial differences of vegetation stability and its carrying capacity in the Amu Darya Basin and the Aral Sea region, and put forward the directions, strategies, key technologies and innovative modes of ecological restoration for the desertification and salinized land. Solving the ecological crisis and desertification in the Aral Sea is one of the key points in the construction of the Green Silk Road, and also an important embodiment of building a community of shared future for mankind and practicing the global values of ecological civilization. [ABSTRACT FROM AUTHOR]

Objective: We studied the diversity of endophytic bacterial communities in different species of halophytes growing in the same saline habitat, and analyzed the effect of rhizosphere soil physicochemical properties on endophytic bacterial communities., Methods: PCR-based Roche FLX 454 pyrosequencing was applied to reveal the diversity of endophytic bacteria., Results: Endophytic bacterial communities of the 16 species of halophytes mainly included 4 phyla, which were Proteobacteria, Tenericutes, Actinobacteria and Firmicutes. In terms of plant species classification, colonial differences existed among plant species at perspectives of composition of bacterial taxa; in the case of plant genus level, endophytic bacteria of different halophyte plant species but belonging to same plant genus exhibited similarity; as to plant family level, Actinobacteria and Proteobacteria comprised the main abundant phyla of the halophytes belonging to Chenopodiaceae; Proteobacteria comprised the main abundant phyla of the halophytes belonging to Zygophyllaceae; Tenericutes comprised the main abundant phyla of the halophytes belonging to Tamaricaceae; Proteobacteria, Fimicutes and Actinobacteria comprised the main abundant phyla of the halophytes belonging to Plumbaginaceae. The Cl- in rhizosphere soil has significant effect on endophytic bacterial community structure. Moreover, there is a strong correlation between bacterial community and the combination of Cl-, Mg2+ and total nitrogen., Conclusion: Halophytes harbors diverse endophytic bacteria. In the same saline habitat, the distribution of endophytic bacteria showed host plant species-specific, and the Cl- in rhizosphere soil was one of the factors determined the endophytic bacterial community.

Objective: This study aimed to describe the composition of the endophytic bacterial communities in Salicornia europaea root, and to examine how endophytic bacteria vary across host growth periods., Methods: PCRbased Roche FLX 454 pyrosequencing was applied to reveal the diversity and succession of endophytic bacteria., Results: A total of 20363 partial 16S rRNA gene sequences were obtained. These sequences revealed huge amount of operational taxonomic units (OTUs), that is, 552-941 OTUs in a root sample. Endophytes in roots mainly comprised four phyla, among which Proteobacteria was the most represented, followed by Firmicutes, Actinobacteria, and Bacteroidetes. Gammaproteobacteria was the most abundant class of Proteobacteria, followed by Betaproteobacteria of this phylum. Genus Azomonas, Serratia, Pantoea, Serpens, Pseudomonas, Halomonas, and Kushneria were shared by all growth stages. Gammaproteobacteria increased during the five stages. The dominant bacterial genera during five periods were related to Delftia, Kushneria, Serratia, Pantoea, Erwinia, respectively. Five libraries contained 2108 unique OTUs with 5 OTUs in common. The greatest number of OTUs was detected during flowering stage. Endophytic bacteria diversity was reduced during fruiting stage. A combination of soil pH, average monthly temperature and soil salt concentration has significant effects on the endophytic bacterial community structure during the five stages., Conclusion: As a whole, the diversity of endophytic bacteria was high inroot of Salicornia europaea. The distribution of endophytic bacteria showed obvious dynamic changes, and the host growth stages determined the endophytic bacterial community.

Based on the geo-morphological and hydro-geological characteristics, the piedmont plain of Tianshan Mountains south slope was classified into 4 geo-morphological belts, i.e., flood erosion belt, groundwater spill belt, delta belt, and the joining belt of piedmont plain and Tarim floodplain. A field investigation on the Tamarix shrub in this region showed that there was a significant difference in its aboveground biomass among the four belts, ranged from 1428.53 kg x hm(-2) at groundwater spill belt to 111.18 kg x hm(-2) at the joining belt of piedmont plain and Tarim floodplain. The main reason for such a big difference might be the different density of Tamarix shrub on different belts. Both the Tamarix aboveground biomass and the topsoil's salinity were decreased with increasing groundwater level. Groundwater level was the main factor limiting Tamarix growth, while soil salinity was not.