Impact of Light Crude Oil Contamination on Seed Germination and Seedling Growth in Zea Mays L

Aiad Abdelkareim Akhreim Alzway — 2025-08-28

This study explores the dose-dependent impacts of light crude oil contamination on seed germination and seedling growth in Zea mays L. (maize), a critical agricultural species. We hypothesized that higher concentrations of light crude oil in soil would progressively suppress germination kinetics and seedling vigor. To test this, Zea mays seeds were exposed to light crude oil at concentrations ranging from 0.0% to 10.0% (v/v) mixed with soil. The experimental design included a control group treated with distilled water to establish baseline germination and growth metrics. Results revealed a clear concentration-dependent phytotoxic effect. Germination percentage significantly declined from 93.3% in the control to 40.0% at 8.0% (v/v) oil concentration (p < 0.05), with complete inhibition of germination observed at 10.0% (v/v). Seedling vigor, assessed through shoot length, exhibited a drastic 93% reduction at 8.0% (v/v) compared to the control, while concentrations up to 4.0% (v/v) showed minimal impact on growth. Germination indices, such as Mean Germination Time (MGT) and Coefficient of Velocity of Germination (CGV), further corroborated the inhibitory effects, with higher oil concentrations delaying and reducing germination rates. These findings suggest a phytotoxicity threshold for Zea mays around 6.0% (v/v) light crude oil, beyond which severe impairments occur. The data provide valuable insights for developing phytoremediation strategies in oil-contaminated agricultural soils. However, the study’s limitations include its focus on a single species and the absence of field-based validation, necessitating further research to confirm these findings under natural conditions and across diverse plant species.

The Effects of Vegetation & Bare Land on Thermal Characteristics: A Case Study of Three Indian Metropolitan Areas

Arpit Gupta — 2025-08-27

Urban expansion in India’s metropolitan regions has led to significant alterations in land surface composition, which directly affect local thermal environments. Vegetation loss and the emergence of bare land surfaces are increasingly recognized as key contributors to urban heat, yet comparative, multi-city studies addressing their combined effects remain scarce. This study analyzes the influence of vegetation and bare land on land surface temperature (LST) across three major Indian cities—Delhi, Lucknow, and Ahmedabad in 2023. Satellite imagery was used to extract Normalized Difference Vegetation Index (NDVI), Normalized Difference Bareness Index (NDBaI), and LST values. Statistical correlation and spatial analysis techniques were applied to evaluate thermal variations across land cover types. NDVI was negatively correlated with LST (r = −0.68 to −0.81), indicating the cooling role of vegetation, whereas NDBaI showed a positive correlation with LST (r = 0.59 to 0.74), highlighting the warming effect of bare surfaces. Delhi exhibited the highest maximum LST (47.45 °C), while Lucknow recorded the highest minimum (38.63 °C). Across all cities and timeframes, vegetated areas consistently showed lower surface temperatures compared to bare or built-up regions. The findings emphasize the importance of vegetation in reducing urban heat and the thermal risk posed by increasing bare land. Strengthening green infrastructure and minimizing exposed soil in urban areas can serve as effective strategies for enhancing thermal comfort and climate resilience in Indian cities.

Research in Ecology

Impact of Light Crude Oil Contamination on Seed Germination and Seedling Growth in Zea Mays L

The Effects of Vegetation & Bare Land on Thermal Characteristics: A Case Study of Three Indian Metropolitan Areas