Effects of Elevation and Distance from Highway on the Abundance and Community Structure of Bacteria in Soil along Qinghai-Tibet Highway

Abstract

In recent years, highway construction in the Qinghai-Tibet Plateau (QTP) has developed rapidly. When the highway passes through grassland, the soil, vegetation, and ecological environment along the line are disturbed. However, the impact on soil bacteria is still unclear. Soil bacteria play an important role in the ecological environment. The Qinghai-Tibet Highway (QTH) was selected as the research object to explore the changes in bacterial community structure, vegetation, soil, and other indicators. The results showed that the highway-related activities increased the degradation of vegetation along the road, significantly changed the physical and chemical properties of soil, and caused heavy metal pollution. These environmental factors affected the diversity and community structure of soil bacteria. This kind of disturbance shows a trend of gradually increasing from near to far from the highway. Gemmatimonas, Terrimonas, Nitrospira and Bacillus are more tolerant to environmental changes along the highway, while Barnesiella, and Blastococcus are more sensitive. The content of nitrate decreased and the content of ammonium nitrogen increased in the disturbed area, increasing the abundance of nitrifying bacteria. Therefore, the main factor of the disturbance of the QTH on the grassland is the decline of soil nutrient content, and the supplement of soil nutrients such as carbon and nitrogen should be taken into account in the process of ecological restoration of grassland along the line.

Modeling of Land Cover Changes in Banjarbaru City South Kalimantan Province

“…Studies have shown that as the distance to roads increases, there are fewer changes in land use and land cover change (Patarasuk & Binford, 2012). Elevation, on the other hand, can affect land cover change through its impact on vegetation and soil conditions (Liu et al, 2021) The results of the altitude and distance to the road can be seen in Figures 3 and 4. The altitude in Banjarbaru is included in the lowland category with an altitude of 0-380 meters.…”

Blastococcus brunescens sp. nov., a member of the Geodermatophilaceae isolated from sandstone collected from the Sahara Desert in Tunisia

“…Blastococcus species have been identified as key components in soils facing diverse challenges, including dryness [2][3][4][5][6][7][8][9][10][11], salinity [43], alkalinity [44], exposure to toxins [45], and notably, heavy metal contamination [46][47][48][49][50]. Consequently, the distribution of genes associated with stress response, antibiotic resistance, as well as resistance to heavy metals and toxic compounds, were evaluated within these genomes.…”

Blastococcus carthaginiensis sp. nov., isolated from a monument sampled in Carthage, Tunisia

“…The genus comprises 14 validly named species, each isolated from various sources. Members of Blastococcus have been identified as pivotal organisms in soils facing diverse challenges, including salinity [4], alkalinity [5], exposure to toxins [6] and, notably, heavy metal contamination [7][8][9][10][11]. Their remarkable adaptability and versatility position Blastococcus species as valuable resources with significant biotechnological potential, encompassing applications in bioremediation, bioleaching, agriculture, enzyme production and the production of potential bioactive molecules.…”