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18 Pags.- 5 Figs.- 1 Tabl. The definitive version is available at: https://onlinelibrary.wiley.com/journal/1099145x, Soil water deficit is one of the important abiotic stresses affecting vegetation restoration. The magnitude and spatiotemporal dynamics of soil water content (SWC) provide basic guidance for optimal vegetation restoration. In a semiarid Chinese area, the changes in the soil water storage (SWS) of five cultivated grasslands and one wasteland were observed, to evaluate the water consumption at different soil depths (0–100 cm), from 2008 to 2012. The plants of the three leguminous species consumed more water in deep soil layers (80–100 cm) and produced more aboveground biomass than the plants of the two gramineous species. The gramineous plants mainly consumed shallow soil water (0 ≤ 30 cm). The soil water deficit in the whole soil profile of Medicago sativa grassland (43–48%) was significantly higher than the deficit of the gramineous grasslands (p, This research was funded by the National Natural Science Foundation of China (NSFC 41722107, 41977063, 41930755), the Key R & D Program of Shaanxi Province (2017NY‐065), and the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences (CAAS‐ASTIP‐2016‐LIHPS‐08).

23 Pags.- 7 Figs. The definitive version is available at: https://onlinelibrary.wiley.com/journal/10991085, Soil water content (SWC) is a key factor for successful vegetation restoration in arid and semiarid regions, and vegetation has significant influences on the spatial patterns and temporal dynamics of SWC. The aim of this study was to investigate the temporal stability of SWC under different restored grasslands in an arid hilly area of Central China. SWC was measured in the 0‐ to 300‐cm soil profile in the natural grassland (Stipa capillata) and three typical planted grasslands (Medicago sativa, Agropyron cristatum, and Caragana korshinskii) over two growing seasons (from June to October 2015 and 2016) under natural rainfall conditions. The results showed that the mean SWC in the natural grassland was approximately 30% higher than those in the planted grasslands. The SWC consumption of the planted legume grasslands in the deepest soil layers (below 200 cm) was higher than that of the natural grassland, owing to the deep root system of the legumes. Both natural and planted grasslands had low SWC temporal stability in the top soil layers (0–50 cm), whereas more stable conditions were gradually observed with increasing the soil depth. The mean value of the mean relative differences of SWC in natural grassland (ca. 15%) was lower than that in the planted grasslands (A. cristatum grasslands) and much lower than that in the scrubland, highlighting the stronger temporal stability of SWC in the natural grassland. In conclusion, natural grassland could maintain higher and stable SWC and is recommended to be used for achieving sustainable vegetation restoration in arid and semiarid regions., This research was funded by the National Natural Science Foundation of China (NSFC41722107, 41525003, 41390463), the West Light Foundation of the Chinese Academy of Science (XAB2015A04), the Youth Innovation Promotion Association of the Chinese Academy of Sciences (2011288), and the Youth Talent Plan Foundation of Northwest A & F University (2452018025), and Open Project Program of Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration of North‐western China/Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in North‐western China of Ministry of Education (2017KF002, 2018KF05).

Delphinium grandiflorum L. is a perennial herb, and has very high medicinal value. However, the evolutionary relationship analysis of D. grandiflorum is limited. Its cp genome was 157,339 bp in length, containing a pair of inverted repeated regions (52,304 bp), separated by a large single copy region of 88,098 bp, and a small single copy region of 16,937 bp. Moreover, a total of 117 functional genes were annotated, including 79 mRNA, 30 tRNA genes, and 8 rRNA genes. The phylogenetic relationships inferred that D. grandiflorum was closely related to Gymnaconitum gymnandrum. This study will provide a theoretical basis for species identification and biological research.

Fruit development in Lycium ruthenicum Murr. involves a succession of physiological and biochemical changes reflecting the transcriptional modulation of thousands of genes. Although recent studies have investigated the dynamic transcriptomic responses during fruit ripening in L. ruthenicum, most have been limited in scope, and thus systematic data representing the structural genes and transcription factors involved in anthocyanin biosynthesis are lacking. In this study, the transcriptomes of three ripening stages associated with anthocyanin accumulation, including S1 (green ripeness stage), S2 (skin color change) and S3 (complete ripeness stage) in L. ruthenicum were investigated using Illumina sequencing. Of a total of 43,573 assembled unigenes, 12,734 were differentially expressed during fruit ripening in L. ruthenicum. Twenty-five significantly differentially expressed structural genes (including PAL, C4H, 4CL, CHS, CHI, F3H, F3'H, F3'5'H, DFR, ANS and UFGT) were identified that might be associated with anthocyanin biosynthesis. Additionally, several transcription factors, including MYB, bHLH, WD40, NAC, WRKY, bZIP and MADS, were correlated with the structural genes, implying their important interaction with anthocyanin biosynthesis-related genes. Our findings provide insight into anthocyanin biosynthesis and regulation patterns in L. ruthenicum and offer a systematic basis for elucidating the molecular mechanisms governing anthocyanin biosynthesis in L. ruthenicum.

Soil water shortage is a critical limiting factor that threaten the growth of vegetation and their sustainability in semi-arid areas. Grasses directly respond to the soil water availability (SWA), and the soil water shortage degree can be studied through plant physiological response thresholds under soil drought stress. In this study, the lower-and-optimal limitation of SWA was evaluated with pots along the soil water gradient by quantifying plant gas exchange parameters. These parameters showed a strong cubic relationship with the relative soil water content (RWC) in four forage species. The lower limitation of RWC was obtained for Onobrychis viciifolia (4.0%–20.2%), followed by Astragalus adsurgens (15.5%–25.5%), Elymus nutans (16.1%–27.2%), and Lolium multiflorum (24.6%–35.8%). The average RWC was of 74.83%, and the water saturation point of water use efficiency (WSPWUE) showed a similar critical scope in the four species: Onobrychis viciifolia (71.2%–82.8%), Astragalus adsurgens (72.1%–84.2%), Elymus nutans (79.3%–85.1%), and Lolium multiflorum (76.7%–85.6%). The highest productivity with the highest availability of water (HPHAW) for Onobrychis viciifolia, Astragalus adsurgens, Elymus nutans and Lolium multiflorum was of 71.2%–82.8%, 72.1%–84.2%, 79.3%–85.1% and 76.7%–85.6%, respectively. The lower limitation of RWC, the maximum water use efficiency (WUEmax) and HPHAW in legumes were lower than those values obtained in gramineae, suggesting that legumes were more susceptible to soil drought stress. We concluded that plant gas exchange parameters acted as indicators for SWA under drought conditions, and represented a valuable tool for identifying SWA threshold response in environmental changes.

The establishment of grasslands on abandoned cropland has been proposed as an effective method to mitigate climate change. In this study, five cultivated grasslands (three leguminous species and two gramineous species), one abandoned cropland, and one natural grassland were studied to examine how soil organic carbon (SOC) sequestration rate and sequestration efficiency change in a semi-arid area in China. Our results showed that leguminous grasslands had greater total biomass (above- and belowground biomass), SOC storage, SOC sequestration rate, and efficiency than gramineous grasslands, abandoned cropland, and natural grassland during the experimental period. The largest soil carbon (C) accumulation in leguminous grassland was mainly attributed to the capacity to incorporate C and the higher biomass production. Leguminous grasslands accumulated more SOC than gramineous grasslands by 0.64 Mg C ha−1 yr−1. The average SOC sequestration efficiency in leguminous grassland (1.00) was about 2 times greater than gramineous grassland (0.34). The results indicate that cultivated leguminous grassland sequestered more SOC with higher SOC sequestration efficiency than cultivated gramineous grassland in arid and semi-arid areas. Our results provide a reference for ecological management in arid and semi-arid areas.

Drought can cause and accelerate the degradation of planted legume grassland, and the changes in plant community composition can further influence soil physical properties. Here, the soil water response of different plant functional groups (legumes, grass, and forbs) were studied along a legume grassland degradation succession according to the above-ground biomass and the proportion of each functional group. In particular, changes in the soil water storage (SWS), soil properties (soil capillary porosity (CP), and soil organic matter) and plant traits (proportion of functional groups and below-ground biomass) were quantified in a continuously cultivated legume grassland for fifteen, sixteen, eighteen, and twenty-two years, without any tillage. The experimental plots were located in the semi-arid region of the Chinese Loess Plateau, in a flat area without runoff contribution. All plant and soil samples, and measurements, were obtained in a few days to minimize the temporal variability. SWS increased at 50–150 cm soil depth when the proportion of legume functional group (LFG) decreased from 70% to 5%, and this increment was ca. 20% at 50–100 cm soil layers. The Shannon-Wiener diversity index (H), the species richness (R), LFG, CP, and the non-capillary porosity (NCP) were significantly correlated with SWS (P, This research was funded by the National Natural Science Foundation of China (NSFC 41722107 and 41525003), the Light of West China Program of Chinese Academy of Sciences (XAB2015A04 and XAB2018B09), and the Youth Talent Plan Foundation of Northwest A&F University (2452018025), and the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences (CAAS-ASTIP-2016-LIHPS-08

Carbon sequestration in grassland soil has been paid considerable attention in recent decades. However, the changes of soil organic carbon (SOC) still need clarification under the effect of environmental factors in semi-arid area. Here, twenty sampling sites were selected to study the effects of plant community (plant cover, biomass, litter, composition and diversity) and environmental factors (i.e. mean annual precipitation, mean annual temperature) on SOC sequestration in the semi-arid grasslands. The results showed that SOC was significant positively related to mean annual precipitation, soil water content and soil pH. The higher above- and below-ground biomass, species evenness and diversity presented the higher SOC. Specially, the species richness and proportion of gramineous species functional group significantly increased SOC. Below-ground biomass affected SOC mainly in the top 30 cm soil. Our results suggest that higher plant species richness and gramineous species proportion play a positive role in increasing the potential of soil carbon sequestration in semi-arid grassland.

The establishment of grassland on abandoned cropland has been proposed as an effective method of mitigating climate change by increasing soil organic carbon (SOC) storage. In this study, five cultivated grasslands were established (three leguminous species – Coronilla varia, Onobrychis viciaefolia, Medicago sativa, and two gramineous species – Poa annua, Agropyron cristatum), one uncultivated, one natural grassland to examine how the SOC storage, sequestration rate and sequestration efficiency to change for 5 years restoration in semi-arid area. Our results showed that the cultivated leguminous grasslands had greater total biomass, SOC storage, SOC sequestration rate and efficiency than gramineous grasslands. The greater soil carbon (C) accumulation in leguminous grassland was mainly attributed to higher biomass production. Leguminous grasslands accumulated more SOC than gramineous grasslands by 0.64 Mg C ha−1 yr−1. The average SOC sequestration efficiency in leguminous grassland (1.00) was about 2 times greater than gramineous grassland (0.34). The results indicate that cultivated leguminous grasslands sequestered more SOC with higher SOC sequestration efficiency than cultivated gramineous grasslands in arid and semi-arid areas.

Successful reclamation of degraded mine land can contribute to recuperate the vegetation and soil carbon sequestration. In this study, soil carbon pool was assessed in a mining land after short-term reclamation. We measured above- and belowground biomass and soil carbon storage of artificial grassland (Astragalus adsurgens and Medicago sativa), which was established in the reclamation of mining land. The results showed that artificial grassland establishment significantly increased above- and belowground biomass after four-year restoration. Artificial grassland establishment increased soil inorganic and organic carbon content and storage. Soil organic and inorganic carbon content showed a positive increasing along the restoration time. Higher SOC and lower soil bulk density and water content all were attributed to the growth of artificial grassland. These results suggest that establishing artificial grassland with legumes is an effective restoration approach for improving soil carbon pool in the reclaimed mine soils.