Showing papers by "Eric C. Brevik published in 2023"

Biological Nanofertilizers to Enhance Growth Potential of Strawberry Seedlings by Boosting Photosynthetic Pigments, Plant Enzymatic Antioxidants, and Nutritional Status

Abstract: Strawberry production presents special challenges due the plants’ shallow roots. The rooting stage of strawberry is a crucial period in the production of this important crop. Several amendments have been applied to support the growth and production of strawberry, particularly fertilizers, to overcome rooting problems. Therefore, the current investigation was carried out to evaluate the application of biological nanofertilizers in promoting strawberry rooting. The treatments included applying two different nanofertilizers produced biologically, nano-selenium (i.e., 25, 50, 75, and 100 mg L−1) and nano-copper (i.e., 50 and 100 mg L−1), plus a control (untreated seedlings). The rooting of strawberry seedlings was investigated by measuring the vegetative growth parameters (root weight, seedling weight, seedling length, and number of leaves), plant enzymatic antioxidants (catalase, peroxidase, and polyphenol oxidase activity), and chlorophyll content and its fluorescence and by evaluating the nutritional status (content of nutrients in the fruit and their uptake). The results showed that the applied nanofertilizers improved the growth, photosynthetic pigments, antioxidant content, and nutritional status of the seedlings compared to the control. A high significant increase in nutrient contents reached to more than 14-fold, 6-fold, 5-folf, and 4-fold for Cu, Mn, N, and Se contents, respectively, due to the applied nanofertilizers compared with the control. The result was related to the biological roles of both Se and CuO in activating the many plant enzymes. Comparing the Se with the CuO nanofertilizer, Cu had the strongest effect, which was shown in the higher values in all studied properties. This study showed that nanofertilizers are useful to stimulate strawberry seedling growth and most likely would also be beneficial for other horticultural crops. In general, the applied 100 ppm of biological nano-Se or nano-CuO might achieve the best growth of strawberry seedlings under growth conditions in greenhouses compared to the control. Along with the economic dimension, the ecological dimension of biological nanofertilizers still needs more investigation.

Assessment of Bioaccumulation of Heavy Metals and Their Ecological Risk in Sea Lettuce (Ulva spp.) along the Coast Alexandria, Egypt: Implications for Sustainable Management

Abstract: The pollution of aquatic ecosystems is an issue facing many countries all over the world and may result in issues such as eutrophication in coastal zones. Managing this eutrophication is a real challenge. The current study focuses on the investigation and identification of aquatic environmental characteristics, including the sediments, waters, and seaweed, of seven eutrophicated locations along the Mediterranean coast of Alexandria (Egypt). Different ecological risk assessment and bioaccumulation factors were calculated in order to identify the probable pollution source and the degree of the problem, in addition to the accumulation of heavy metals in the seaweed. The characteristics of the seaweed, sediments, and waters were chemically analyzed and heavy metals were measured. The genetically and biochemically identified seaweed species were Ulva compressa, Ulva fasciata, Ulva lactuca and Ulva linzea. The sediments of the El-Tabia location contained the highest concentrations of Cd, Co, Ni, and Pb, because this location receives these elements from the El-Amia drain. The Abu Qir location was found to contain the highest concentrations of the same heavy metals in the studied water samples because it was located much closer to the Abu Qir harbor. Ecological risk assessment indices indicated moderate to high contamination for most of the studied elements and locations. The results of the bioaccumulation factor analysis indicated that the studied seaweed species are accumulators of trace elements. These seaweed species should be further investigated concerning ecotoxicology if they are to be used in the human diet and for other benefits. This study opens many windows of research to be investigated in the future regarding the sustainable management of polluted coastal zones.

Soil evolution in basaltic parent materials under successive climate changes, Saudi Arabia

Abstract: This study was designed to investigate the successive effects of the early Pleistocene subhumid and early to middle Holocene semi-arid paleoclimates and late Holocene to present day arid/hyperarid conditions on pedogenesis and evolution in Harrat Ithnayn volcano in the Arabian Shield, Saudi Arabia. The investigations were conducted using pedological macro and micro-features, physicochemical characteristics, elemental geochemistry, weathering indices and mineralogical analyses for light and heavy sand and clay fractions. The targeted soils developed in a subhumid paleoclimate and are classified as vitric Andisols, which are little to moderately weathered. Subhumid climate effects were evident through the presence of pedogenic Fe (crystalline oxides, Fed = 25 to 58 g kg─1), fairly high Feo/Fed (0.24 to 0.87), and the predominance of hydroxy-Al smectite and kaolinite. Residual primary minerals and modern arid conditions simultaneously led to accumulation of secondary salts and carbonates. Exchangeable Ca and Mg pools contributed 21–56 % of total Ca and Mg contents, while exchangeable K contributed only up to 4 %. Soil processes thus involved andisolization, salinization, and calcification. These processes were due to successive moist paleoclimates and the current arid conditions, thus revealing their formation under multiple climates.

Eastern red cedar effects on carbon sequestration and soil quality in the Great Plains

Abstract: Eastern red cedar (ERC, Juniperus virginiana L.) is a common tree species in agroforestry plantings and has great potential for bioenergy production due to physical and chemical characteristics of its biomass. The objective of this study was to assess the effects of ERC plantings on carbon (C) sequestration and selected soil quality parameters in existing plantings across the northern U.S. Great Plains. Nine locations were selected in five states with mean annual precipitation (MAP) from 446 to 999 mm and mean annual temperature (MAT) from 4.4 to 10.0 °C. Infiltration was measured using the twin ring technique at nine sites in each tree planting and adjacent field (crop, pasture, or hay) at each location. Following infiltration measurements, a 4.8 cm.-diameter soil core to 30 cm depth was collected from inside one infiltration ring of each pair for bulk density, pH, aggregate stability, soil organic carbon (SOC), and total nitrogen (TN) analyses. Penetration resistance in 2.5 cm increments to 30 cm depth was measured in the other infiltration ring. SOC stocks under ERC were significantly higher than in the adjacent field soil at five of the locations and, for all locations, averaged 16.8% greater than in the adjacent field. The estimated SOC accumulation rate for the eight locations with uniform tree stand age averaged 0.30 Mg C ha yr. Most locations had higher TN and C/N and lower bulk density beneath ERC. Fewer differences for infiltration and penetration resistance and smaller and less consistent differences for pH and aggregate stability were observed. Tree aboveground C stocks were estimated to increase an average of 2.05 Mg C ha yr. Estimated tree aboveground biomass C and SOC stocks under ERC and in adjacent fields were strongly correlated with MAP. Potential ERC planting for C sequestration or bioenergy feedstock production is not likely to significantly degrade soil quality and may improve soil physical or chemical quality for locations in the U.S. Great Plains. This article is protected by copyright. All rights reserved

Nanofarming: Promising Solutions for the Future of the Global Agricultural Industry

Abstract: The agricultural sector is a vital source of human well-being that provides the necessities of daily life. A variety of farming systems are utilized in agriculture, such as a wide range of tillage options, no-till, agroforestry, precision farming, organic farming, cover cropping, crop rotations, etc. Each of these farming systems has unique challenges, and nanotechnology has successfully improved on many of them. Agricultural applications of nanotechnology include nanofertilizers, nanopesticides, nanosensors, nanobiotechnology, and nanoremediation. This study focuses on the application of nano-farming technologies to different farming systems. Suggested practices include nano improvement of soil quality, crop nano-protection under biotic stress, nanoremediation of polluted soil and water environments, nanomanagement of agro-wastes, nano-agrochemicals, nano-precision farming, and nanobiotechnology for modern farming. This review also addresses expected problems that may occur due to over application of nanomaterials to farming systems, such as nanopollution and nanotoxicity of agroecosystem compartments. Several dimensions are emphasized in this study, such as green energy, sustainable development, the circular bioeconomy, land biodegradation, pollution, and the one health approach, as essential for the global goals of sustainable development. Nanofarming presents both benefits and obstacles to human life. The exact balance between these benefits and challenges needs more study.