Land production potential (LPP) was the maximum grain yield in one year that can be produced by land under the limitations of climate conditions and in the absence of pests and diseases and other factors. Whether climate change was increasing or reducing the LPP in a given region was uncertain. Therefore, Shaanxi Province was selected to analyze the regional differences in climate change and its effects on LPP change and to identify the main climatic factor restricting LPP in different regions by combining Global Agro-Ecological Zone (GAEZ) model with the Geodetector model. Results showed that the temperature in Shaanxi Province showed an upward trend in 2000–2015; the rise in temperature to the north of Qinling Mountain (QM) was less than that to the south of QM. However, rising temperature had a yield-improving effect to the north of QM and a yield-decreasing effect to the south of QM. There was a precipitation increase in Arid Sandy (AS) area and Loess Plateau (LP), and the precipitation reduced in all other geographical units. The increase in LPP of Shaanxi mostly was caused by increasing precipitation. However, precipitation was declined and reduced LPP to the south of QM; that is, precipitation decline was the dominated climatic factor for LPP decrease in QM, Hanjiang Basin (HB), and Daba Mountain (DM). To the north of QM, LPP in AS, LP, and Guanzhong Plain (GP) both dramatically increased, mainly improved by rising temperature, increasing precipitation, and rising temperature, respectively.

Due to serious nitrogen pollution in the Huai River, Eastern China, nitrogenous concentrations and dual stable isotopes (δ¹⁵N and δ¹⁸O) were measured to ascertain the sources and transformation of nitrogen in the Shaying River, the largest and most polluted tributary of the Huai River during the summer and winter seasons. Total nitrogen (TN), NO₃⁻, and NH₄⁺ were significantly higher in winter, with values of 7.84 ± 3.44 mg L⁻¹, 2.31 ± 0.81 mg L⁻¹, and 3.00 ± 2.24 mg L⁻¹, respectively, while the highest nitrogen compounds occurred in the Jialu River, one of the tributaries of the Shaying River, in both summer and winter. Isotope characteristics of nitrate reveal that manure and sewage were the principal nitrate sources in both summer (62.44 ± 19.66%) and winter (67.33 ± 15.45%), followed by soil organic nitrogen, with 24.94 ± 15.52% in summer and 26.33 ± 9.45% in winter. Values of δ¹⁵N-suspended particulate nitrogen (SPN) ranged from 0.78 to 13.51%, revealing that point source from industrial and domestic sewage accounted for the largest input to SPN at most sites, whereas soil organic nitrogen and agricultural fertilizers were found in the Jialu River in both sampling periods. Point sources from septic/manure and household waste were the main contributors to ammonium in most river water samples in both summer and winter; most wastewater discharged into the river was untreated, which was one of the main reasons for the high level of ammonium in winter. Nitrogen pollution and the dams had an effect on N transformation in the river. Significant assimilation of NH₄⁺ and aerobic denitrification competed for NH₄⁺, resulting in the weakness of nitrification in the summer. Denitrification was also an important process of nitrate removal during the summer, whereas nitrification was a key N transformation process in the river in the winter time. To reduce nitrogen pollution and improve water quality, greater effort should be focused on the management of sources from urban input as well as on the improvement in sewage treatment.

From the perspective of river basin refined management and pollution control of water bodies, a transboundary river basin and its regional pollutant sources are identified and the typical status of discharging processes of different pollutant sources are screened. Then organic connection which can comprehensively reflect and dynamically characterize the discharge of transboundary water pollutants is constructed. In addition, the integrated prediction (IP) model of the transboundary river basin and its regional water pollutants discharge is established. Finally, the dynamic simulation of typical status characteristics of the transboundary river basin and its regional pollutant sources discharge as well as the tempo-spatial changing pattern of pollutant discharge intensity is conducted in this paper. This paper selected the Songhua River basin as an example where planting, industry, household (urban living and rural living), and livestock and poultry are the main pollutant sources. The dynamic simulation of water pollution discharge in Songhua River basin during the 13th Five-year Plan and its tempo-spatial changing trend analysis are conducted by employing the established IP model of transboundary river basin water pollution discharge. The results show that during the 13th Five-year Plan, through comprehensive management and control of pollutant sources in Songhua River basin, the discharge amounts of different pollutant sources (planting, industry, household, livestock, and poultry) present an overall decreasing trend and the main pollutants discharge intensity decreases significantly year by year. It is demonstrated that pollution discharge in Songhua River basin is controlled effectively.

Glutathione (GSH) is involved in not only plant developmental processes but also plant responses to abiotic stresses. A hydroponic experiment was performed to explore the protective roles of exogenous GSH in mitigating cadmium (Cd) stress in Brassica campestris L. seedlings by analyzing the morphological and physiological parameters. Results showed that Cd caused severe growth inhibition and Cd accumulation. However, application of GSH significantly mitigated toxic symptoms induced by Cd, including the improvement of the photosynthesis-, plant growth-, and root morphology-related parameters in seedlings under Cd stress. These responses were associated with a striking increase in activities of representative antioxidative enzymes and contents of corresponding non-enzymatic antioxidants. In vivo imaging of O₂.⁻ and H₂O₂, and the detection of lipid peroxidation further demonstrated that increased ability by GSH for Brassica campestris L. seedlings to endure Cd stress was consistent with a striking elevation of ratios of reduced to oxidized glutathione (GSH/GSSG) and ascorbic acid to dehydroascorbic acid (AsA/DHA). Additionally, GSH application increased Cd retained in roots, thus significantly decreased its translocation from root to shoot, ultimately decreased Cd accumulation in shoots. Taken together, our results proved evidence for GSH in ameliorating Cd toxicity via reducing Cd accumulation in shoots and increasing oxidation resistance. Accordingly, application of GSH could be a high-efficiency and promising strategy to decrease Cd concentration in edible parts of Brassica campestris L. in agricultural production.

This study involves the climate change impact assessment of wheat producers in Khyber Pakhtunkhwa, Pakistan. An extensive farm survey of 150 farms was designed. From study area, three districts, namely, Chitral, D.I. Khan, and Peshawar, were selected through multistage sampling process. Yield simulation from Crop model DSSAT (Decision Support System for Agro Technology Transfer) was used for socio-economic impact assessment. Future climate scenarios were generated by selecting five GCMs from latest CMIP5 family with two RCPs 4.5 and 8.5, at two carbon concentrations of 499 ppm and 571 ppm, respectively. Yield simulations were analyzed for each GCM. Results of crop model revealed that wheat yield will increase in district Chitral, while in D.I. Khan and Peshawar, yields would be reduced due to climate change. For socio-economic impact assessment, TOA-MD (Trade-Off Analysis for Multi-Dimensional Impact Assessment) version 6 was used. Climate change impacts on poverty, net farm returns, and per capita income were calculated for different scenarios. The analysis was carried out on per-farm basis. The economic model results revealed that climate change has negative impact on wheat producers in D.I. Khan and Peshawar while making wheat producers better off in Chitral. The number of losers ranged from 54 to 66.21% and 50 to 61.99% in D.I. Khan and Peshawar, respectively. Losers are the farmers who would be economically worse off under perturbed climate. With current climate, the observed poverty rate would be 34 to 49 in D.I. Khan while 21.26 to 34.03 in Peshawar. The study recommended need for adaptation strategies to overcome the vulnerabilities of climate change.

Organophosphate esters (OPEs) are a kind of emerging contaminants, but the information about their pollution profile and ecological risk are still scarce in China. In this study, 31 surface water samples of Haihe River (China) were collected in November 2017, and 11 OPEs were measured, and the ecological risk of OPEs was assessed by means of species sensitivity distribution (SSD) method and assessment factor method. Additionally, Pearson correlation analysis and an international comparison with other rivers in the world were conducted. The results showed that total OPEs ranged from 23.98 to 824.72 ng L⁻¹, and the mean value was 228.70 ng L⁻¹. The concentration of OPEs decreased as follows: Tri(2-chloroisopropyl) phosphate (TCPP) > Tri(2-chloroethyl) phosphate (TCEP) > Triethyl phosphate (TEP) > Tributoxyethyl phosphate (TBEP) > Triphenyl phosphate (TPhP) > Tripropyl phosphate (TPrP) > Tri(2-ethylhexyl) phosphate (TEHP) > 2-ethylhexyl diphenyl phosphate (EHDPP) > Tri(1,3-dichloro-2-propyl)phosphate (TDCPP) > Tri-n-butyl phosphate (TnBP) > Tri-m-cresyl phosphate (TMPP). TCPP (19.54–160.82 ng L⁻¹) and TCEP (N.D.-151.99 ng L⁻¹) with the mean value of 76.67 and 53.13 ng L⁻¹ respectively were identified as the richest OPEs in Haihe River. The concentration of OPEs slowly increased in the upper reaches of Haihe River, and it tended to be stable in the middle reaches of Haihe River and decreased rapidly from the downstream to the outer sea. Significantly positive correlations occurred among three chlorinated alkyl OPEs (TCEP, TCPP, and TDCPP), suggesting that they might come from the same source. Based on the comparison, the pollution condition of OPEs in Haihe River was low, and TCEP was found to be the most abundant OPEs in China but it was not that in Europe. The ecological risk assessment on the basis of assessment factor method suggested that the risk of OPEs in Haihe River for algae, crustacean, and fish was limited. In addition, the results of SSD method suggested that the combined ecological risk of four OPEs in Haihe River was also low. This study provides information about the pollution status of OPEs in the surface water of China to some extents and a project for the risk estimation based on SSD for prior and emerging flame retardants.

The standardized precipitation index (SPI) and the standardized precipitation evapotranspiration index (SPEI) based on two different methods were calculated using monthly meteorological data from the Yangtze River Basin. According to the completeness and length of dataset, the monthly data of 35 meteorological stations from 1959 to 2017 were applied in this study. The results revealed that the SPEI calculated by the Penman-Monteith (PM) method performed better than the SPI and the SPEI based on the Thornthwaite (TH) method. Since SPEI_PM considered more meteorological factors and detailed physical processes, it obtained the most reasonable and accurate results of drought trends. Using the variations of SPEI_PM to analyze the decadal changes of drought characteristics in the basin, it could be found that 1980–1989 and 1990–1999 were the most humid periods in the basin, while the drought events became more frequent and severe in the recent decade. The spatial distributions of drought trend, duration and frequency indicated that the stations located in the midstream of the river were most prone to drought events, followed by the upper reaches. Our results provided more information for the regions where severe droughts occurred frequently and last longer, and more attention should be paid to these regions in future catchment management.

Because of its low concentration, its unique physico-chemical properties and the analytical difficulties associated with its measurement, the determination of mercury species in solids is not an easy task. Thermal desorption (HgTPD) is an attractive option for the identification of mercury species in solids due to its simplicity and accessibility. However, there are still issues that need to be solved for it to reach its full potential. One such issue is the availability of reference materials that will reproduce real mercury associations. The novelty of this study is the use of six uncommon mercury minerals, taken from around the world, and a sphalerite sample to expand the data base of reference materials for mercury speciation by thermal desorption at programmed temperature. In addition, by using such materials, a number of matrix effects can be ascertained. Different mercury associations were identified depending on the temperature of desorption, thereby validating the thermal desorption as a reliable technique for mercury speciation in solid samples and as a consequence improving the knowledge of the geochemistry of mercury in the environment.