Effect of Saline Water for Drip Irrigation on Microbial Diversity and on Fertility of Aeolian Sandy Soils

Saline water is widely distributed in the arid environment and sometimes represents the only source of irrigation water to restore and reconstruct vegetation. However, the effects of saline water on the bacterial diversity and fertility level of aeolian sandy soil are not well understood. In this study, we investigated a vegetation belt along the Tarim Desert Highway that has been constructed as a windbreak and consists of desert shrubs and was irrigated with saline water at six levels of salinity along the Tarim Desert Highway. The bacterial diversity was studied using Biolog Eco, a phospholipid fatty acid analysis, and a polymerase chain reaction–denaturing gradient gel electrophoresis, and the soil fertility was calculated and expressed as the integrated fertility index. The soil bacterial diversity (in terms of carbon metabolism, genes, and fatty acid species) was significantly affected by the level of salinity, and the microbial activity was low under high salinity. Fertility was also markedly affected by the degree of salinity and by the depth of soil, being lower at higher salinity levels and in the top layer (0–5 cm), and was also correlated to both the metabolic diversity index of soil microorganisms and the diversity index of fatty acids of soil microorganisms. The genetic diversity index of soil microorganisms shared a polynomial relation with fertility and contributed to it positively and significantly. Therefore, using less saline water for drip irrigation could avoid salt accumulation in soil and arrest its compaction, promote the formation of soil aggregates and the build-up of nutrients, and increase microbial activity, thus playing a crucial role in promoting the circulation, conversion, and utilization of nutrients in aeolian sandy soils and improving the soil quality. The judicious use of saline water, therefore, deserves serious consideration in irrigation practices.

Bioprospecting of Soil-Derived Actinobacteria Along the Alar-Hotan Desert Highway in the Taklamakan Desert

Taklamakan desert is known as the largest dunefield in China and as the second largest shifting sand desert in the world. Although with long history and glorious culture, the Taklamakan desert remains largely unexplored and numerous microorganisms have not been harvested in culture or taxonomically identified yet. The main objective of this study is to explore the diversity, novelty, and pharmacological potential of the cultivable actinomycetes from soil samples at various sites along the Alar-Hotan desert highway in the Taklamakan desert. A total of 590 actinobacterial strains were recovered by the culture-dependent approach. Phylogenetic analysis based on 16S ribosomal RNA (rRNA) gene sequences unveiled a significant level of actinobacterial diversity with 55 genera distributed in 27 families of 12 orders. Thirty-six strains showed relatively low 16S rRNA similarities (<98.65%) with validly described species, among which four strains had already been characterized as novel taxa by our previous research. One hundred and forty-six actinobacterial isolates were selected as representatives to evaluate the antibacterial activities and mechanism of action by the paper-disk diffusion method and a double fluorescent protein reporter “pDualrep2” system, respectively. A total of 61 isolates exhibited antagonistic activity against the tested “ESKAPE” pathogens, among which seven strains could produce bioactive metabolites either to be able to block translation machinery or to induce SOS-response in the pDualrep2 system. Notably, Saccharothrix sp. 16Sb2-4, harboring a promising antibacterial potential with the mechanism of interfering with protein translation, was analyzed in detail to gain deeper insights into its bioactive metabolites. Through ultra-performance liquid chromatography (UPLC)-quadrupole time-of-flight (QToF)-MS/MS based molecular networking analysis and databases identification, four families of compounds (1–16) were putatively identified. Subsequent bioassay-guided separation resulted in purification of four 16-membered macrolide antibiotics, aldgamycin H (8), aldgamycin K (9), aldgamycin G (10), and swalpamycin B (11), and their structures were elucidated by HR-electrospray ionization source (ESI)-MS and NMR spectroscopy. All compounds 8–11 displayed antibacterial activities by inhibiting protein synthesis in the pDualrep2 system. In conclusion, this work demonstrates that Taklamakan desert is a potentially unique reservoir of versatile actinobacteria, which can be a promising source for discovery of novel species and diverse bioactive compounds.

The view from ‘pre-Crusader’ Shawbak: towards a first contextualization through GIS visibility and spatial analyses

The view from ‘pre-Crusader’ Shawbak: towards a first contextualization through GIS visibility and spatial analyses The purpose of this study is to provide a first preliminary interpretation of part of the evidence from Shawbak castle which attests to the presence of a ‘pre-Crusader, probably Byzantine fort. The strategic features of the location of the fort, in particular a great abundance of water resources, made it indeed strategically advantageous during the Crusader period and in the later Ayyubid and Mamluk periods. Stratigraphic evidence from readings of extant buildings and excavations revealed that the first Crusader foundation of the castle was laid out upon the remains of a LateRoman/Byzantine fortification identified in different parts of the castle. The presence of such fortification should probably be considered contextual to the presence of major forts and potential watchtower sites that have been documented by previous surveys in the area, in particular, a system of strategic locations depending on the castellum of Da’janiya betweenthe Desert highway to the east and the Via Nova Traiana to the west. The need to protect the fertile strip of land east of Shawbak and the natural resources of the area might have required a system of visual control attested to in other nearby regions, which could have involved a signaling network in communication with Shawbak. In this paper, a series of visibility analyses are proposed in order to demonstrate that such system could have worked for Byzantine Shawbak.

Influence of plantation of a shelter-belt on component of organic carbon in the Taklimakan desert over last decade

The soils were collected from the Taklimakan Desert Highway shelter-belt with different planting years in Xinjiang, northwest of China. The soil organic carbon stork (SOCstork) in each layers. By chemical and physical pretreatment, we measured four carbon passive organic carbons, i.e., microaggregates organic carbon(OCMIA), humus organic carbon (OCHS), carbon resistance to oxidation (OCNaClO) and acid hydrolysis (OCHCl). The results showed that the OC and SOCstork was decreased with soil depth mainly in 0-50 cm. The artificial vegetation have more influence on TOC, OCMIA and OCHS than OCNaClO and OCHCl. The Tamarix chinensis shelter-belt is the most helpful for carbon sequestration in sandy soil and stabilization in surface layer than Calligonum mongolicunl and Haloxylon ammodendron.

MINAT BELI KONSUMEN TOKO SEPATU BATA DIPASAR RAYA PADANG DILIHAT DARI SIKAP DAN IKLAN

The company is engaged in the manufacture, import, export and distribution of leather shoes, built-up canvas, casual and sports shoes, injection slippers, and special shoes for industry. This study aimed to analyze the influence of each variable, the attitude (X1), advertising (X2) toward purchase intention. Data were collected through questionnaires. to 100 respondents Bata store consumer markets desert highway by using accidental sampling method to determine the respondents to each variable. By using the validity test, reliability test, descriptive analysis, multiple linear regression analysis, the coefficient of determination (R2), t-test, f. Data analysis technique used is multiple linear analysis. The result of this study shows that attitude and advertising have a significant effect on consumer buying interest in the purchase of shoes brick desert highway market.