[Soil organic carbon density and its influencing factors in croplands with different cultivation years in the Northeastern Ulan Buh Desert, China].

Understanding the changes and influencing factors of soil organic carbon density (SOCD) during the conversion of uncultivated natural soil to croplands is of great significance for the assessment of carbon sequestration in arid areas. In this study, we compared SOCD in the uncultivated soil and that in croplands with different cultivation years (2-5, 12-15, 25-30, 40-50 years) in the Northeastern Ulan Buh Desert. The change of SOCD and its influencing factors at 0-2 m soil depth during the conversion of uncultivated natural soil to croplands were explored by the method of replacing time with space.

[Research progress on soil aggregates and associated organic carbon in salinized soils].

Soil aggregate, as a basic component of soils, plays an important role in improving soil structure and enhancing soil organic carbon (SOC) sequestration. The special soil properties induced by salinization, such as high ion concentrations (mainly Na), shortage of organic material and bad condition of microbe, inhibit the formation and stability of soil aggregate. Therefore, it is important and meaningful to explore the dynamics of aggregate in salinized soils.

Diversity and functional characteristics of endophytic bacteria from two grass species growing on an oil-contaminated site in the Yellow River Delta, China.

Phragmites australis and Chloris virgata are native, dominant, salt-tolerant grass species that grow in the Yellow River Delta, China, and have potential applications in the phytoremediation of petroleum-polluted saline soil. The characteristics of endophytic bacterial communities of Phragmites australis and Chloris virgata and their functions in hydrocarbon degradation and plant growth promotion have been studied using both high-throughput sequencing and conventional microbial techniques. Through 16S rRNA gene amplicon sequencing, we found five bacterial phyla that were dominant among the endophytic bacterial communities of the two grass species, including Proteobacteria, Actinobacteria, Firmicutes, Bacteroidetes, and Tenericutes.

[Effects of biochar and EM application on growth and photosynthetic characteristics of in saline-alkali soil of the Yellow River Delta, China].

We examined the effects of biochar and effective mircoorganisms (EM) application on growth and photosynthetic characteristics of in the Yellow River Delta, by a pot experiment with different EM treatments (without EM addition, EM-; with EM addition, EM+) and a gradient of biochar treatments (0, B; 0.5%, B; 1.5%, B; 3%, B; biochar weight/soil weight).

Physiological and ecological characteristics of Periploca sepium Bunge under drought stress on shell sand in the Yellow River Delta of China.

This study investigated the physiological and ecological changes in P. sepium Bunge and elucidated the physiological regulatory mechanisms underlying the adaptation of P. sepium to drought stress in shell sand.

[Soil amelioration of different vegetation types in saline-alkali land of the Yellow River Delta, China].

Yellow River Delta is an important distribution area of coastal saline-alkali land in China. Revegetation is the main technology for ecological restoration during saline-alkali land amelioration. To explore the effects of different vegetation types on soil improvement in saline-alkali land and get the suitable model in the Yellow River Delta, four tree-grass compound models, Salix americana+Distichlis spicata, S.

[Quality level assessment of lowly efficient Tamarix chinensis secondary shrubs in Laizhou Bay of Yellow River Delta].

Taking the Tamarix chinensis secondary shrubs in Laizhou Bay of Yellow River Delta as test objects, and by using synthetic factor method, this paper studied the main factors causing the lowly efficiency of T. chinensis secondary shrubs as well as the main parameters for the classification of lowly efficient T. chinensis secondary shrubs.

[Light response of Wisteria sinensis leaves physiological parameters under different soil moisture conditions].

With two years old Wisteria sinensis as test material, this paper measured the light response of its leaves net photosynthetic rate (Pn), transpiration rate (Tr) and water use efficiency (WUE) under different soil moisture conditions, aimed to ascertain the optimal soil moisture and light conditions of W. sinensis growth. The results showed that the Pn, Tr and WUE had evident threshold responses to the variations of soil moisture and light intensity.