Oilseed rape (Brassica napus) characteristically has high N uptake efficiency and low N utilization efficiency (NUtE, seed yield/shoot N accumulation). Determining the NUtE phenotype of various genotypes in different growth conditions is a way of finding target traits to improve oilseed rape NUtE. The aim of this study was to compare oilseed rape genotypes grown on contrasting N supply rates in pot and field experiments to investigate the genotypic variations of NUtE and to identify indicators of N efficient genotypes. For 50 oilseed rape genotypes, NUtE, dry matter and N partitioning, morphological characteristics, and the yield components were investigated under high and low N supplies in a greenhouse pot experiment and a field trial. Although the genotype rankings of NUtE were different between the pot experiment and the field trial, some genotypes performed consistently in both two environments. N-responder, N-nonresponder, N-efficient and N-inefficient genotypes were identified from these genotypes with consistent NUtE. The correlations between the pot experiment and the field trial in NUtE were only 0.34 at high N supplies and no significant correlations were found at low N supplies. However, Pearson coefficient correlation (r) and principal component analysis showed NUtE had similar genetic correlations with other traits across the pot and field experiment. Among the yield components, only seeds per silique showed strong and positive correlations with NUtE under varying N supply in both experiments (r = 0.47**; 0.49**; 0.47**; 0.54**). At high and low N supply, NUtE was positively correlated with seed yield (r = 0.45**; 0.53**; 0.39**; 0.87**), nitrogen harvest index (NHI, r = 0.68**; 0.82**; 0.99**; 0.89**), and harvest index (HI, r = 0.79**; 0.83**; 0.90**; 0.78**) and negatively correlated with biomass distribution to stem and leaf (r = −0.34**; −0.45**; −0.37**; 0.62**), all aboveground plant section N concentration (r from −0.30* to −0.80**), N distribution to the vegetative parts (silique husk, stem and leaf) (r from −0.40** to −0.83**). N-efficient (N-responder) genotypes produced more seeds per silique and had significantly higher NHI and HI than did N-inefficient (N-nonresponder) genotypes. In conclusion, across the pot and field experiments, the 50 genotypes had similar underlying traits correlated with NUtE and seeds per silique may be a good indicator of NUtE.

The Cd(II) adsorption of kiwi biochar functionalized with Mg-Fe (3:1) layered double hydroxides (LDH) was studied. And the biochar was got via liquid-phase deposition, by incorporating Mg-Fe layered double hydroxide (Mg-Fe LDH) particles into kiwi biochar (KB/ LDH). The batch of sorption experiments were studied, including adsorption kinetics and isotherm and the effects of pH, ion strength (IS) and co-existing ions. The KB/LDH composite showed a strong sorption ability to Cd(II) in aqueous solutions with the adsorption capacity of 25.6 mg g −1 , compared with pristine biochar of 1.78 mg g −1. The adsorption of Cd(II) on KB/ LDH composite increased with the decreasing of IS, decreased first and then grew larger with the increase of pH and was observed irrespective of the coexistence of K + , Cl − and NO 3 −. To sum up, the KB/LDH can be potentially used as an alternative adsorbent to amend the water and soil contaminated by Cd(II).

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We aim to understand the distribution of soil moisture and its controlling factors for regional vegetation restoration in a semi-arid sandy land. The top 500 cm soils of the main introduced vegetation types restored for different years in Chinese Mu Us Sandy Land were collected, and the soil moisture and influencing factors were analyzed. The results demonstrated that the total soil water storage decreased in a sequence of shrub land (S) ˃ arbor land (A) ˃ shifting sandy land (CK) ˃ grassland (G). With the increase of restoration period, the soil moisture increased in arbor land and decreased first and then increased in both shrub land and grassland. Soil moisture was negatively correlated (P < 0.05) with root length density (RLD) in G 56 , S 36 , A 21 , and S 21. RLD and soil moisture in S 56 showed an extremely significant negative correlation (P < 0.01). Soil water content had a positive correlation with silt content (P < 0.05) but demonstrated a negative correlation with the sand content (P < 0.05) in A 56. Both silt and sand contents showed negative correlations with soil moisture in G 56 (P < 0.05). In summary, vegetation type, restoration period, RLD, and silt and clay contents have significant effects on soil moisture. To improve the soil moisture status, arbors and bushes should be preferentially considered for vegetation restoration in semi-arid northwest of China.