Salinity stress is one of the primary abiotic stresses limiting crop growth and yield. Plants respond to salinity stress with several morphophysiological, molecular, and biochemical mechanisms, however, these mechanisms need to be improved further to cope with salt stress effectively. In this regard, the use of plant growth-promoting (PGP) and halotolerant bacteria is thought to be very efficient for enhancing growth and salinity tolerance in plants. The current study aims to assess Bacillus safensis PM22 for its ability to promote plant growth and resistance to salt. The PM22 produced substantial amounts of exopolysaccharides, indole-3-acetic acid, siderophore, and 1-aminocyclopropane-1-carboxylic acid deaminase (ACC-deaminase) under saline conditions. Additionally, inoculation of the halotolerant bacteria PM22 reduced the severity of salinity stress in plants and increased root and shoot length at various salt concentrations (0, 180, 240, and 300 mM). Furthermore, PM22-inoculated plants showed markedly enhanced photosynthetic pigment, carotenoid, leaf relative water content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) activity, salt tolerance index, total soluble sugar, total protein, and ascorbic acid contents compared to non-inoculated control maize plants. PM22 substantially increased antioxidant (enzymatic and non-enzymatic) activities in maize plants, including ascorbate peroxidase, peroxidase, superoxide dismutase, catalase, total flavonoid, and phenol levels. Maize plants inoculated with PM22 also exhibited a significant reduction in electrolyte leakage, hydrogen peroxide, malondialdehyde, glycine betaine, and proline contents compared to non-inoculated control plants. These physiological appearances were further validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), which revealed the upregulation of expression in genes responsible for stress tolerance. In the current investigation, Bacillus safensis PM22 showed plant growth-promoting and salt tolerance attributes and can be utilized as a bio-inoculant to improve yield in salt stress affected areas.

Xanthium strumarium L. is a globally successful invasive herb that has had significant negative ecological, economic and social impacts in many world regions. The present study was therefore conducted to evaluate the invasive potential and spatial distribution patterns of X. strumarium in heavily invaded plant communities of the semiarid regions of northern Pakistan. Investigations were based on data from 20 plants grown in the Herbarium at the University of Malakand, and from observations in 450 plots distributed across 45 stands representing habitats across Northern Province including open fields, hillocks and abandoned areas in both urban and rural areas. Multivariate analysis identified elevation, organic matter and organic carbon as the environmental variables most associated with communities invaded by X. strumarium. Increased soil silt was positively associated and available water was negatively associated with X. strumarium–invaded communities. These key environmental characteristics allowed us to identify four main associations: Group I: X. strumarium-C. sativa, Group II: X. strumarium-P. hysterophorus, Group III: X. strumarium-A. aspera and Group IV: X. strumarium-C. sativa. Other invasive species were observed, either exotic, such as P. hysterophorus, or indigenous, such as C. sativa and D. inoxia, often co-occurring and responding similarly to these factors. The results suggest that high temperature with drought stress could be a determinant of increasing population at lower elevations, whereas colder climates with adequate moisture are related to reduced populations at higher elevations, near the species’ upper range limits. It is recommend that the inclusion of appropriate, additional soil and climatic variables in species distribution models be implemented in order to better explain species’ ecological niches and help guide conservation and protection plans for native plant communities.

Global biodiversity management is of concern due to invasive plant species that dramatically disturb the native communities causing biological homogenization. Therefore, the present research investigated the impacts of Silybum marianum, an aggressive invasive alien species, on communities’ diversity and environmental variables in Khyber Pakhtunkhwa, Pakistan. Phytosociological characteristics and diversity indices of the communities were sampled in seventy-five sites using the quadrate method. These sites were categorized based on invasion intensities, i.e., fully invaded sites with a 100% importance value index of the selected species, severely invaded sites with >60% of IVI, and partially invaded sites with >30% of the chosen species. The community composition significantly changes with changes in invasion intensity. Similarly, S. marianum invasion has a pronounced impact on the community’s diversity showing significant differences among the three categorized groups (p < 0.05). The canonical correspondence analysis revealed 29.9% variance where soil texture, nutrients, and elevations were influential variables in maintaining the community’s structure and composition. The study concludes that S. marianum dominated well-established communities in the existing soil and environmental variables; therefore, it was found to be influential in disturbing the native communities and may severely harm the crop plant and agricultural system in the future.

A specific set of environmental conditions characterizes plant species patterns and distribution on Earth. Similarly, riparian vegetation can be impacted by anthropogenic activities like mining practices involving the removal of vegetation cover, which destroys the structure and diversity of the habitat, adversely affecting the ecosystem services. In this study, we explored the role of environmental variables and biotic intervention in deriving spatial patterns and distribution of riparian vegetation at mining and non-mining sites along the most depleted Panjkora River basin in NW Pakistan. Vegetation data and its determining factors at 28 mining and non-mining sites (14 each) were sampled using 10 m × 10 m (100 m²) systematic plots at 50 m intervals along transects in a downstream direction from the upper catchments to the bottom junction with the Swat River. We recorded 186 species in both mining and non-mining sites, belonging to 70 families comprising 174 angiosperms, 3 gymnosperms, and 9 Pteridophytes. Results show that annual or perennial therophytic life forms predominated in the Panjkora River system, indicating anthropogenic disturbances. At the same time, the aggressively invasive species, such as Xanthium strumarium and Cannabis sativa, further heightened plant community disturbances. Generally, the species diversity was higher in non-mining sites and may be attributed to habitat fragmentation. Likewise, the Canonical Correspondence Analysis (CCA-ordination) revealed that geographic coordinate (i.e., latitude r = 0.80; longitude r = 0.75) and elevation (r = 0.95) were more meaningful predictors than soil texture (i.e., silt%, r = −0.30), nutrients (i.e., potassium, r = −0.35; phosphorus, r = 0.38) and soil pH (r = −0.50) in shaping the spatial pattern and vegetation structure. Our result implies that the present vegetation composition and spatial assemblages are due to heavy anthropogenic interventions, especially mining activities. Therefore, the heavily degraded fragile riparian system of the Panjkora River and its tributaries needed to be conserved and restored by predicting the composition of communities in response to changing climatic conditions.

Pheasants play a distinctive and significant role in high altitudinal ecosystems. These are good indicators of environmental changes, and their presence determines the health and balance of the bio-network. Recent human pressure continues to degrade their populations, and some pheasant species are already extinct. Therefore, the current study focuses on pheasant abundance and emerging conservation issues. The pheasant population was assessed using “Call count methods” and analyzed by DISTANCE software. The results revealed that the valleys where human interference is minimum had significantly higher encounter rates and densities of pheasants. At the same time, the pheasant population was severely affected, whether found at lower or higher altitudes, showing seasonal migration toward human settlements. The habitat suitability modeling was performed using the MaxEnt model and showed that human activities overlap with the suitable natural habitats of pheasants. The threats were identified using a systematic questionnaire survey from the nearest villages of the potential habitat, and particular attention was paid to valleys where human pressures were found to be high. Major infrastructure development projects, illegal hunting, and deforestation were identified as the major threats to the pheasant population. The study concluded that proper conservation measures are required to protect pheasants in their potential habitats.

This research aimed to investigate the bioaccumulation and health risk associated with absorption of the selected heavy metals (HMs) i.e., lead (Pb), cadmium (Cd), zinc (Zn), and copper (Cu) in a wild leafy vegetable Nasturtium officinale that grows along the Swat River in swampy areas. The areas were categorized using the ecological risk index (RI), which indicates how heavy metal concentrations in soil and plants change over time. The bioaccumulation factor was greater than that at the 400 ≤ RI sites, indicating a probable health risk of these metals from N. officinale consumption. Furthermore, the health risk index for Cd and Pb was more significant, i.e., greater than one in the majority of the samples, indicating health concerns associated with consuming N. officinale from the study site. However, Zn and Cu levels were lower than the nutritionally needed levels, raising the risk of deficiency in the population. Plants cultivated in Pb and Cd-polluted sites were nutrient deficient in Cu and Zn. Intake of such plants can expose people to HM contamination and nutritional deficiencies. The results concluded that the plants accumulated significant HM contents and may have health concerns but are safe for consumption in children and adults.