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Background Multiprotein bridging factor 1 (MBF1) is a crucial transcriptional coactivator in animals, plants, and some microorganisms, that plays a necessary role in growth development and stress tolerance. Zanthoxylum armatum is an important perennial plant for the condiments and pharmaceutical industries, whereas the potential information in the genes related to stress resistance remains poorly understood in Z. armatum.  Results Herein, six representative species were selected for use in a genome-wide investigation of the MBF1 family, including Arabidopsis thaliana, Oryza sativa, Populus trichocarpa, Citrus sinensis, Ginkgo biloba, and Z. armatum. The results showed that the MBF1 genes could be divided into two groups: Group I contained the MBF1a and MBF1b subfamilies, and group II was independent of the MBF1c subfamily.. Most species have at least two different MBF1 genes, and MBF1c is usually an essential member. The three ZaMBF1 genes were respectively located on ZaChr26, ZaChr32, and ZaChr4 of Zanthoxylum chromosomes. The collinearity were occurred between three ZaMBF1 genes, and ZaMBF1c showed the collinearity between Z. armatum and both P. trichocarpa and C. sinensis. Moreover, many cis-elements associated with abiotic stress and phytohormone pathways were detected in the promoter regions of MBF1 of six representative species. The ERF binding sites were the most abundant targets in the sequences of the ZaMBF1 family, and some transcription factor sites related to floral differentiation were also identified in ZaMBF1c, such as MADS, LFY, Dof, and AP2. ZaMBF1a was observed to be very highly expressed in 25 different samples except in the seeds, and ZaMBF1c may be associated with the male and female floral initiation processes. In addition, expression in all the ZaMBF1 genes could be significantly induced by water-logging, cold stress, ethephon, methyl jasmonate, and salicylic acid treatments, especially in ZaMBF1c. Conclusion The present study carried out a comprehensive bioinformatic investigation related to the MBF1 family in six representative species, and the responsiveness of ZaMBF1 genes to various abiotic stresses and phytohormone inductions was also revealed. This work not only lays a solid foundation to uncover the biological roles of the ZaMBF1 family in Z. armatum, but also provides some broad references for conducting the MBF1 research in other plants.

Phytoremediation is a useful tool to restore heavy metals contaminated soils. This study was carried out to test two castor (Ricinus communis) cultivars [Local and DS-30] for phytoextraction of heavy metals from the soil spiked by known concentrations of seven metals (Cu, Cr, Fe, Mn, Ni, Pb and Zn). A pot experiment was laid out by using a completely randomized design. Soil and plant samples were analyzed at 100 days after planting. The data on heavy metal uptake by plant tissues (roots, leaves and shoots) of the two castor cultivars suggested that a considerable amount of metals (Fe = 27.18 mg L-1; Cu = 5.06 mg L-1; Cr = 2.95 mg L-1; Mn = 0.22 mg L-1; Ni = 4.66 mg L-1; Pb = 3.33 mg L-1; Zn = 15.04 mg L-1) was accumulated in the plant biomass. The soil heavy metal content at the end of experiment significantly decreased with both cultivars, resulting in improved soil quality. Therefore, it is concluded that both castor cultivars, Local and DS-30, can be used for phytoremediation of heavy metal-contaminated sites.

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Afforestation on cultivated farmlands causes major shifts in the nitrogen (N) cycle. The consequences of large‐scale Zanthoxylum bungeanum afforestation on spatio‐temporal patterns of soil N mineralization and inorganic N (ION) availability have not been reported. Moreover, the regulatory roles of microbial biomass and soluble organic N (MBN and SON) in the N cycle are poorly characterized in soils below 20 cm. To investigate the long‐term effects of afforestation on the governing mechanism of vertical N dynamics, a 0–100 cm soil profile was collected from a chronosequence of Z. bungeanum plantations aged 8‐year (H8), 15‐year (H15), 20‐year (H20) and 28‐year (H28), as well as adjacent farmland and abandoned‐land (28‐year) as controls in an arid valley in Southwest China. With increasing stand age, conversion of farmland to Z. bungeanum plantations significantly improved soil organic carbon, available nutrients, and all N forms. These impacts were more evident in the topsoil (0–20 cm) than in the subsoil layers. MBN and SON contents improved by 1.42‐fold and 1.34‐fold in H28, respectively, compared to H8. Net N mineralization (1.31‐fold), net nitrification rates (1.30‐fold), and total ION (1.31‐fold) content followed similar trends of increase along with the stand age. Correlation and redundancy analysis also established a positive relationship and demonstrated that increased ION availability is due to improved MBN, SON, and urease activity with the plantations age. Although the nitrate‐N content was highest in abandoned‐land, its content also increased steadily in Z. bungeanum plantations with the stand age. A relatively low ammonium/nitrate ratio (0.331) in H28 advocated improved N supply via nitrification as well as low N leaching risks from plantations. The spatial investigation provided novel insights into controls of N cycle and suggested converting farmland to Z. bungeanum plantations is a suitable approach for restoring soil N.

Aims Plant-soil interactions, and regulatory roles of soil nitrogen (N) fractions in availability and the magnitudes of N sequestration, therein the interplay of soil C-N in cold arid regions is poorly characterized. Methods Post-afforestation and land-abandonment dynamics of C and N sequestration, and total inorganic N (TIN) availability were identified by quantifying changes in diverse N fraction, and their distributions patterns in 0–100 cm soil profile across a chronosequence of Zanthoxylum bungeanum (28-year (H28), 20-year (H20), 15-year (H15), and 8-year (H8) old) plantations, and abandoned-land (GL), originally converted from former farmland (FL) in cold-arid valley in Southwest China. Results Afforestation and GL favored gains in labile and non-labile (LON and NLON) N fractions and total N stocks. Concentrations of LON fractions and TIN was comparatively higher at 0–40 cm. Gains in NLON fractions and total organic N (TON) was significantly higher in the deep soil, as confirmed by correlation and redundancy analysis. N and C sequestration was synchronous (r = 0.948), with cumulative (0–100 cm) increase of 1.149–1.277 folds in H28 compared to H8, at an average sequestration rate of 1.336 − 0.121 Mg ha − 1 yr − 1, respectively. N pool management index (NPMI) correlated positively with soil TON, TIN, available phosphorus, potassium, and organic N fractions. NPMI improved significantly (P < 0.05) with the plantations age. Conclusion Plantations age and soil depths significantly influence ecosystems N dynamics. Furthermore, TON, NPMI, N fractions, and TIN can be useful indicators to gain comprehensive insights on ecosystems N restoration patterns.

Farmland conversion to forest is considered to be one of the effective measures to mitigate climate change. However, the impact of farmland conversion to forest land or grassland on soil CO2 emission in arid areas is unclear due to the lack of comparative information on soil organic carbon (SOC) mineralization of different conversion types. The SOC mineralization in 0–100 cm soil layer in farmland (FL), abandoned land (AL) and different ages (including 8, 15, 20 and 28 years) of Zanthoxylum bungeanum plantations were measured by laboratory incubation. The size and decomposition rate of fast pool (Cf) and slow pool (Cs) in different land-use types and soil layers were estimated by double exponential model. The results showed that: 1) Farmland conversion increased the cumulative CO2-C release (Cmin) and SOC mineralization efficiency, and those indexes in AL were higher than that in Z. bungeanum plantations. The Cmin and SOC mineralization efficiency of 0–100 cm soil increased with the ages of Z. bungeanum plantation. Both Cmin and SOC mineralization efficiency decreased with the increase of soil depth; 2) Both soil Cf and Cs increased after farmland converted to Z. bungeanum plantations and AL. The Cs in the same soil layer increased with the ages of Z. bungeanum plantation, and the Cf showed a “V” type with the increased ages of Z. bungeanum plantation. The Cf and Cs decreased with the increase of soil depth in all land-use types; 3) Farmland conversion increased the decomposition rate of Cf (k1) in all soil layer by 0.008–0.143 d−1 and 0.082–0.148 d−1 in Z. bungeanum plantations and AL, respectively. The k1 was obviously higher in the 0−20 cm soil layer than that in other soil layers, while the decomposition rate of Cs (k2) was not affected by FL conversion and soil depth; and 4) The initial soil chemical properties and enzyme activity affected SOC mineralization, especially the concentrations of total organic nitrogen (TON), SOC, easily oxidizable organic carbon (EOC) and microbial biomass carbon (MBC). It indicated that the conversion of farmland to Z. bungeanum plantations and AL increases SOC mineralization, especially in deeper soils, and it increased with the ages. The conversion of farmland to Z. bungeanum plantation is the optimal measure when the potential C sequestration of plant-soil system were taken in consideration.

The interaction of warming and soil texture on responsiveness of the key soil processes i.e. organic carbon (C) fractions, soil microbes, extracellular enzymes and CO2 emissions remains largely unknown. Global warming raises the relevant question of how different soil processes will respond in near future, and what will be the likely regulatory role of texture? To bridge this gap, this work applied the laboratory incubation method to investigate the effects of temperature changes (10–50 °C) on dynamics of labile, recalcitrant and stable C fractions, soil microbes, microbial biomass, activities of extracellular enzymes and CO2 emissions in sandy and clayey textured soils. The role of texture (sandy and clayey) in the mitigation of temperature effect was also investigated. The results revealed that the temperature sensitivity of C fractions and extracellular enzymes was in the order recalcitrant C fractions > stable C fractions > labile C fractions and oxidative enzymes > hydrolytic enzymes. While temperature sensitivity of soil microbes and biomass was in the order bacteria > actinomycetes > fungi ≈ microbial biomass C (MBC) > microbial biomass N (MBN) > microbial biomass N (MBP). Conversely, the temperature effect and sensitivity of all key soil processes including CO2 emissions were significantly (P < 0.05) higher in sandy than clayey textured soil. Results confirmed that under the scenario of global warming and climate change, soils which are sandy in nature are more susceptible to temperature increase and prone to become the CO2-C sources. It was revealed that clayey texture played an important role in mitigating and easing off the undue temperature influence, hence, the sensitivity of key soil processes.