27 research outputs found
Key decomposers of straw depending on tillage and fertilization
No full texthttp://dx.doi.org/10.13039/501100004775 Natural Science Foundation of Gansu Provincehttp://dx.doi.org/10.13039/501100018647 RUDN Universityhttp://dx.doi.org/10.13039/501100001809 National Natural Science Foundation of Chin
Long-term effect of manure and fertilizer on soil organic carbon pools in dryland farming in northwest China.
No full textAn understanding of the dynamics of soil organic carbon (SOC) as affected by farming practices is imperative for maintaining soil productivity and mitigating global warming. The objectives of this study were to investigate the effects of long-term fertilization on SOC and SOC fractions for the whole soil profile (0-100 cm) in northwest China. The study was initiated in 1979 in Gansu, China and included six treatments: unfertilized control (CK), nitrogen fertilizer (N), nitrogen and phosphorus (P) fertilizers (NP), straw plus N and P fertilizers (NP+S), farmyard manure (FYM), and farmyard manure plus N and P fertilizers (NP+FYM). Results showed that SOC concentration in the 0-20 cm soil layer increased with time except in the CK and N treatments. Long-term fertilization significantly influenced SOC concentrations and storage to 60 cm depth. Below 60 cm, SOC concentrations and storages were statistically not significant between all treatments. The concentration of SOC at different depths in 0-60 cm soil profile was higher under NP+FYM follow by under NP+S, compared to under CK. The SOC storage in 0-60 cm in NP+FYM, NP+S, FYM and NP treatments were increased by 41.3%, 32.9%, 28.1% and 17.9%, respectively, as compared to the CK treatment. Organic manure plus inorganic fertilizer application also increased labile soil organic carbon pools in 0-60 cm depth. The average concentration of particulate organic carbon (POC), dissolved organic carbon (DOC) and microbial biomass carbon (MBC) in organic manure plus inorganic fertilizer treatments (NP+S and NP+FYM) in 0-60 cm depth were increased by 64.9-91.9%, 42.5-56.9%, and 74.7-99.4%, respectively, over the CK treatment. The POC, MBC and DOC concentrations increased linearly with increasing SOC content. These results indicate that long-term additions of organic manure have the most beneficial effects in building carbon pools among the investigated types of fertilization
Trends in grain yields and soil organic C in a long‐term fertilization experiment in the China Loess Plateau
No full text
Long‐Term Fertilizer and Water Availability Effects on Cereal Yield and Soil Chemical Properties in Northwest China
No full textAtomic-Scale Imaging of Organic-Inorganic Hybrid Perovskite Using Transmission Electron Microscope
No full textTransmission electron microscope (TEM) is thought as one powerful tool to imaging the atomic-level structure of organic inorganic hybrid perovskite (OIHP) materials, which provides valuable and essential guidance toward high performance OIHP-related devices. However, these OIHPs exhibit poor electron beam stability, severely limiting their practical applications in TEM. Here in this article, the application of TEM to obtain atomic-scale image of OIHPs, main obstacles in identifying the degradation product and future prospects of TEM in the characterization of OIHP materials are reviewed and presented. Three potential strategies (sample protection, low temperature technology, and low-dose technologies) are also proposed to overcome the current drawback of TEM technology
Plastid genome comparison and phylogenetic analyses of the Chinese group of medicinal species and related taxa within Asparagus genus
No full textBackgroundAsparagus L. is a large genus widely distributed across the continents of the Old World. Among its members, approximately 14 species found in China are recognized as popular herbal medicines. However, accurate authentication of these medicinal species and their phylogenetic relationships with related taxa remains unresolved.MethodsTo identify simple sequence repeats (SSRs) and divergence hotspot regions appropriate for future authentication studies, as well as to infer the phylogenetic relationships among Asparagus species, we employed a plastid genome (plastome) dataset consisting of 25 Asparagus species (21 newly sequenced and four retrieved from GenBank), encompassing 12 Chinese medicinal species, for comparative and phylogenetic analyses.ResultsAll Asparagus plastomes displayed a typical quadripartite structure with sizes ranging from 155,948 bp to 157,128 bp and harbored 114 unique genes (80 protein-coding genes, 30 tRNA genes, and four rRNA genes). IRscope and Mauve analyses indicated minimal structural variation among Asparagus plastomes. We detected between 79 to 95 SSRs across the plastomes; most were located in the large single-copy (LSC) region and primarily consisted of mono-nucleotide repeat sequences (especially A and T repeats). The genus displayed mono-, di-, tri-, tetra-, penta-, and hexa-nucleotide repeats, but with variations in types and numbers among different species. Additionally, we identified 12 special SSR motifs and seven divergent hotspot regions that may serve as potential molecular markers for future identification efforts. Phylogenetic analyses yielded a robust phylogeny for Asparagus taxa, which were split into Clades I, II, and III. Notably, medicinal Asparagus species were mainly found in Clade III. Although the phylogenetic relationships of most Asparagus species aligned with previous study findings, the phylogenetic positions of A. munitus, A. subscandens, A. gobicus, and A. dauricus were newly determined.ConclusionsThe plastomes of Asparagus are largely conserved in terms of genome structure, size, gene content, and arrangement. Nevertheless, SSRs analyses revealed significant interspecific polymorphism within Asparagus. In addition, special SSR motifs and divergent hotspot regions identified from Asparagus plastomes provided reference for subsequent identification investigations. The plastome-based phylogeny provided preliminary insights into the relationships among the Chinese group of medicinal species and related taxa within Asparagus. Overall, this study offers a wealth of informative genetic resources pertinent to Asparagus, thereby enhancing our understanding of its evolution and laying a foundation for species identification, assessment of genetic population diversity, as well as the exploration and conservation of germplasm resources
Effect of long-term fertilizer applications on depth distribution of bulk density (A), soil organic C (B) and soil organic C storage (C).
No full text<p>Effect of long-term fertilizer applications on depth distribution of bulk density (A), soil organic C (B) and soil organic C storage (C).</p
Effects of plastic mulching on the accumulation and distribution of macro and micro plastics in soils of two farming systems in Northwest China
No full textBackground: Inappropriate disposal of the plastic mulching debris could create macroplastics (MaPs) and microplastics (MiPs) pollution in agricultural soil. Methods: To study the effects of farming systems on accumulation and distribution of agricultural plastic debris, research was carried out on two farming systems in Northwest China. Farming in Wutong Village (S1) is characterized by small plots and low-intensity machine tillage while farming in Shihezi (S2) is characterized by large plots and high-intensity machine tillage. In September 2017, we selected six fields in S1, three fields with 6–8 years of continuous plastic mulching (CM) as well as three fields with over 30 years of intermittent mulching (IM). In S2, we selected five cotton fields with 6, 7, 8, 15 and 18 years of continuous mulching. In both regions, MaPs and MiPs from soil surface to 30 cm depth (0–30 cm) were sampled. Results: The results showed that in S1, MaPs mass in fields with 6–8 years CM (i.e., 97.4kg·ha−1) were significantly higher than in fields with 30 years IM (i.e., 53.7 kg·ha−1). MaPs in size category of 10–50 cm2 accounted for 46.9% in fields of CM and 44.5% in fields of IM of total collected MaPs number. In S2, MaPs mass ranged from 43.5 kg·ha−1 to 148 kg·ha−1. MaPs in size category of 2–10 cm2 account for 41.1% of total collected MaPs number while 0.25–2 cm2 accounted for 40.6%. MiPs in S1 were mainly detected in fields with over 30 years of intermittent mulching (up to 2,200 particles·kg−1 soil), whereas in S2 were detected in all fields (up to 900 particles·kg−1 soil). The results indicated farming systems could substantially affect the accumulation and distribution of agricultural plastic debris. Continuous plastic mulching could accumulate higher amount of MaPs than intermittent plastic mulching. High-intensity machine tillage could lead to higher fragmentation of MaPs and more severe MiPs pollution. These results suggest that agricultural plastic regulations are needed
Probing Surface Information of Alloy by Time of Flight-Secondary Ion Mass Spectrometer
No full textIn recent years, time of flight-secondary ion mass spectrometer (ToF-SIMS) has been widely employed to acquire surface information of materials. Here, we investigated the alloy surface by combining the mass spectra and 2D mapping images of ToF-SIMS. We found by surprise that these two results seem to be inconsistent with each other. Therefore, other surface characteristic tools such as SEM-EDS were further used to provide additional supports. The results indicated that such differences may originate from the variance of secondary ion yields, which might be affected by crystal orientation
