The current research encompasses utilization of peanut shells (PS) as feedstock for pyrolysis carried out at various temperatures (250, 400, and 550 °C) for deriving biochar, namely PS-BC250, PS-BC400, and PS-BC550. After analyzing the biochar types physicochemically, it was applied as a soil ameliorant for the growth of cucumber. The results showed that in prepared biochar type, bulk density, volatile contents, hydrogen, oxygen, and nitrogen content decreased, whereas pH, electrical conductivity, ash content, fixed carbon content, and surface area increased with the increasing temperature. Scanning electron microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) presented high porosity, re-orientation of vessels, and a greater number of aromatic compounds, respectively, for PS-BC prepared at 550 °C. On applying PS-BC250, PS-BC400, and PS-BC550 as amendments in potted soil at 2, 4, and 6% (w/w), it improved soil quality (viz pH, EC_e, BD, and soil water holding capacity) and increased the yield of cucumber. Because of improved soil properties and crop yield, PS-BC550 at the rate of 4% (w/w) demonstrated a great potential for agricultural application while provisioning dual circular economic indicators in the form of diverting PS waste to an effective alternative of chemical fertilizer having intensive carbon footprints in cucumber production.

Globally, biological invasions are considered as one of the major contributing factors for the loss of indigenous biological diversity. Hyperspectral remote sensing plays an important role in the detection and mapping of invasive plant species. The main objective of this study was to discriminate invasive plant species from adjacent native species using a ground-based hyperspectral sensor in two protected areas, Lehri Reserve Forest and Jindi Reserve Forest in Punjab, Pakistan. Field spectral measurements were collected using an ASD FieldSpec handheld2^TM spectroradiometer (325–1075 nm) and the discrimination between native and invasive plant species was evaluated statistically using hyperspectral indices as well as leaf wavelength spectra. Finally, spectral separability was calculated using Jeffries Matusita distance index, based on selected wavebands. The results reveal that there were statistically significant differences (p < 0.05) between the different spectral indices of most of the plant species in the forests. However, the red-edge parameters showed the highest potential (p < 0.001) to discriminate different plant species. With leaf spectral signatures, the mean reflectance between all plant species was significantly different (p < 0.05) at 562 (75%) wavelength bands. Among pairwise comparisons, invasive Leucaena leucocephala showed the best discriminating ability, with Dodonaea viscosa having 505 significant wavebands showing variations between them. Jeffries Matusita distance analysis revealed that band combinations of the red-edge region (725, 726 nm) showed the best spectral separability (85%) for all species. Our findings suggest that it is possible to identify and discriminate invasive species through field spectroscopy for their future monitoring and management. However, the upscaling of hyperspectral measurements to airborne and satellite sensors can provide a reliable estimation of invasion through mapping inside the protected areas and can help to conserve biodiversity and environmental ecosystems in the future.

The current study is aimed at deriving biochar (BC) from rice straw (RS-BC) and waste bones (WB-BC), being wasted without adequate return at the expense of environmental degradation. The RS and WB feedstocks were pyrolyzed at 550 °C, and the potential of derived biochar as a slow nutrient releasing soil amendment was examined during the growth of ridge gourd. Proximate analysis of the prepared biochars showed significant improvement in ash content and fixed carbon as compared to their raw biomasses. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) analysis of RS-BC and WB-BC displayed a diverse range of functional groups viz. derivatives of cellulose and hydroxylapatite (HA); macro and microporosity; multiple nutrients. Application of RS-BC and WB-BC in potted soil alone and as biochar composite (RS-BC+WB-BC) at 5, 10 and 15% (w/w) and chemical fertilizer (CF) resulted in a significant increase in soil pH, electrical conductivity (ECe), cation exchange capacity (CEC) and water holding capacity (WHC) in exchange for growth and yield of ridge gourd. However, there were insignificant differences in the growth of plants in response to RS-BC, WB-BC alone and CF with biochar composite at 15% amendment. For giving insignificantly different growth results than CF, the prepared biochar composite showed outstanding potential as an organic fertilizer applicable in agrarian soils to elevate soil properties and yield of agricultural commodities.