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The Sugan Lake Basin is located in the inland arid region of northwestern China, in which groundwater is of great significance to human and ecology. Therefore, it is necessary to understand the chemical characteristics and quality of groundwater in the basin. Based on samples collected from 35 groundwater wells in Sugan Lake Basin, the spatial distribution characteristics of groundwater chemistry, main hydrogeochemical processes and groundwater quality have been discussed in this paper by using the multivariate statistics and hydrochemistry analysis methods. The results showed that the groundwater is weakly alkaline, and its total dissolved solid (TDS) and total hardness (TH) are high, with the average values of 1244.03 mg/L and 492.10 mg/L, respectively. The types of groundwater are mainly HCO3−-SO42−-Ca2+ type in the runoff area and Cl−-SO42−-Na+ type in the catchment area. Rock weathering and ion exchange are the main controlling factors of regional groundwater chemistry, followed by evaporative crystallization, and human activities have less impact on groundwater. The spatial difference of groundwater quality is obvious, the water quality of the catchment area is not suitable for drinking, and the suitability for plant growth is also poor. The groundwater in the runoff area can be used for drinking, but the hardness is slightly higher, which is more suitable for ecological purpose.

Flour beetles of the genus Palorus (Coleoptera: Tenebrionidae) are important secondary storage pests. Correct identification of these insects is urgently required for integrated pest management. However, traditional morphological classification methods cannot identify insect fragments or immature stages and require skilled taxonomists with training and experience. In this study, three Palorus species were distinguished with two molecular techniques; DNA barcoding and species-specific PCR based on the mitochondrial DNA cytochrome oxidase subunit I (COI) gene. Forty-nine individuals of Palorus subdepressus (Wollaston), Palorus ratzeburgi (Wissman) and Palorus cerylonoides (Pascoe) were collected from 19 different locations across rice processing factory, feed factory, flour mill and bulk storages China. The COI sequences were analyzed by K2P distances and neighbor-joining (NJ) tree for DNA barcoding. The results show that these three Palorus species can be successfully identified by DNA barcoding. For the species-specific PCR study, we designed specificity primer pairs for the three Palorus species and evaluated their sensitivity. The results showed that the three Palorus species can be identified by the species-specific PCR method. Our results indicated that the two techniques can be independently used to identify the Palorus species in China for integrated pest management and quarantine. This is the first time Palorus species have been identified using two molecular techniques and the P. ratzeburgi and P. cerylonoides data have filled a gap in BOLD and GenBank.

An efficient and simple protocol for the synthesis of aryl azides by the coupling of aryl iodides with sodium azide, in good to excellent yields in DMSO at 95 °C under catalysis by Cu(OAc)2-H2O and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), has been established. The optimised loadings of Cu(OAc)2-H2O and DBU were 10 mol% and 15 mol% respectively.

An efficient and green copper(II) acetylacetonate-catalyzed protocol for the Huisgen-click reaction in water at 100 °C has been established. The protocol was not only suitable for the reaction between organic azides and alkynes, but also suitable for one-pot three-component reaction among alkyl halides, NaN3 and alkynes.

Soil, as the largest organic carbon pool of terrestrial ecosystem, plays a significant role in regulating the global carbon cycle, atmospheric carbon dioxide (CO2) levels, and global climate change. It is of great significance to scientifically understand the change rule and influence mechanism of soil organic carbon (SOC) to further understand the "source&ndash, sink" transformation of SOC and its influence on climate change. In this paper, the spatiotemporal distribution characteristics and influencing mechanism of SOC were analyzed by means of field investigation and laboratory analysis and the measured data in the Eastern Qilian Mountains. The results showed that the average SOC content of 0&ndash, 50 cm was 35.74 &plusmn, 4.15 g/kg and the range of coefficients of variation (CV) between 48.84% and 75.84%, which suggested that the SOC content exhibited moderate heterogeneity at each soil layer of the Eastern Qilian Mountains. In four land cover types, the SOC content of forestland was the highest, followed by alpine meadow, grassland, and wilderness, which presented surface enrichment, and there was a decreasing trend with the soil depth. From the perspective of seasonal dynamics, there was a uniform pattern of SOC content in different land cover types, shown to be the highest in winter, followed by autumn, spring, and summer, and with the biggest difference between winter and summer appearing in the surface layer. At the same time, our study suggested that the SOC content of different land cover types was closely related to aboveground biomass and negatively related to both the mean monthly temperature and the mean monthly precipitation. Therefore, the distribution and variation of SOC was the result of a combination of climate, vegetation, and other factors.

Groundwater chemistry has an important impact on the vegetation distribution in inland areas. An in-depth understanding of the impact of groundwater chemistry on vegetation can help in developing an effective management strategy to protect the inland ecosystem. The aim of this study was to identify the influence of groundwater chemicals on species diversity and the distribution characteristics of wetland plants at multiple scales based on the groundwater chemical data from 15 sampling points and the distribution data of 13 plants in the Sugan Lake Wetland in 2016. The results show that the groundwater of the Sugan Lake Wetland is weakly alkaline, with high salinity and hardness, the water chemical type is Na-SO4-Cl, the concentration of the major water chemical parameters is significantly different and is the highest in the northwest, followed by the southwest, and is the lowest in the east, with an increase in the groundwater depth, the concentration of major water chemical parameters first showed an increasing trend followed by a decreasing trend, Artemisia frigida Willd, Poa annua L and Triglochin maritimum L were adapted to the environment with a higher ion concentration of the groundwater, and their salt resistance was the strongest, Blysmus sinocompressus and Polygonum are more adapted to the environment with lower salinity and hardness of groundwater, Thermopsis lanceolata has stronger adaptability to the ion concentration, salinity, and hardness of groundwater, other plants are adapted to environments where the ion concentration, salinity, and hardness of the groundwater are moderate.

The Shiyang River Basin is a typical arid watershed in Northwest China. Scientific understanding of the driving mechanism of runoff change is the basis of scientific utilization of water resources and regional sustainable development. In this study, runoff changes at different time scales were analyzed for the period 1960–2018, and the impacts of climate variability and human activities on runoff were investigated in the middle and lower reaches of the Shiyang River Basin (SRB). A combination of mutation analysis and human-designed analysis was adopted to divide the study period into the baseline period and the variation period. The Mann–Kendall test (M−K) and Double Mass Curve method (DMC) were used to detect abrupt changes and quantify the relative effects of climate change and human activities on runoff. The results reveal a significant declining trend in annual runoff on the whole in the middle and lower reaches of the SRB, and there was an obvious recovery trend after the implementation of the Comprehensive Treatment Program of the SRB (CTSRB) in 2007. Abrupt changes occurred in 1976, 1991 and 2007, which divided the study period into the baseline period (1960–1975), the Variation Ⅰ period (1976–1990), the Variation Ⅱ period (1991–2006) and the Variation III period (2007–2018). The contribution of human activities to runoff reduction was 88.72%, whereas the contribution of climate change to runoff reduction was only 11.28%. Furthermore, the contribution of human activities to runoff reduction in the Variation Ⅰ period, Variation Ⅱ period and Variation III period was 89.44%, 93.02% and 83.69%, respectively. Therefore, human activities played the most dominant role in the variation of runoff, followed by climate change and upstream runoff. Further analysis of the impact of human activities on runoff indicated that agricultural irrigation was the dominant factor of runoff reduction. This study can provide detailed information on water resources and a scientific basis for the development and utilization of water resources in the future.

As an important means to cope with global climate change, ecological restoration projects have a huge impact on ecosystem carbon storage functions. Scientifically evaluating the response process and mechanism of basin ecosystem carbon storage functions in ecological restoration projects is beneficial to the improvement of regional ecosystems. Taking Shiyang River Basin (SRB) as an example, and based on the perspective of “carbon sink–carbon source” mutual transformation, the current study utilized the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model to analyze the spatio-temporal dynamics of carbon storage in SRB, quantified the effect of ecological restoration projects on the ecosystem carbon fixation capacity, and identified sensitive and vulnerable areas of carbon loss against the background of climate and land use/cover change (LUCC). The results show that the ecosystem carbon storage in SRB changed significantly before and after the ecological project implementation, with a decrease of 5.71 Tg in 1986–2000 and an increase of 14.11 Tg in 2000–2016. The proportion of carbon sink enhancement areas was only 7.46% in 1986–2000, which increased to 15.04% in 2000–2016, indicating that the ecological restoration effect of the watershed was obvious as a result of the ecological management. The contribution of LUCC brought about by the ecological restoration project to the increase in ecosystem carbon storage was as high as 103.71%, for which the increase in woodland and grassland was the key. However, in 2000–2016, low carbon optimization areas accounted for 4.17% and carbon emission control areas for 6.16% of the total area of SRB. The carbon fixation capacity of these areas declined, and carbon emissions were elevated, especially in carbon emission control areas. These were mainly distributed in the oasis–desert transition zone in the mid-lower reaches, which are sensitive and vulnerable areas for carbon loss. Therefore, in future ecological restoration and protection processes, these areas should be given more attention and protection.

A convenient CuI/DBU catalyzed one-pot method has been developed for the synthesis of 1,4-disubstituted 1,2,3-triazoles through the coupling of aryl iodides with sodium azide, followed by the intermolecular cyclization between the generated aryl azides and phenylacetaldehyde derivatives or alkynes in DMSO. The established protocol was compatible with a wide scope of substrates in good to excellent yields.