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2023 ◽  
Vol 83 ◽  
Author(s):  
G. A. Paula ◽  
E. Fischer ◽  
M. Silveira ◽  
H. Almeida ◽  
E. van den Berg

Abstract Although richness and distribution of woody species in the Cerrado physiognomies have been extensively studied, the shifts of woody species from savanna physiognomies to dry forests have not yet been addressed. Here, we investigate the effect of soil physical-chemical traits on the woody species turnover between adjacent cerrado stricto sensu and dry forest physiognomies. Woody species were surveyed, and soil and topographic variables measured, in 30 10×40 m plots systematically distributed, with 15 plots in each physiognomy. We found a spatially structured distribution of woody species, and differences of soil traits between cerrado stricto sensu and dry forest areas, mainly related to the aluminum saturation, base saturation, and available phosphorus. Aluminum saturation increased toward the savanna area, while base saturation increased toward the dry forest. Most woody species predominated in one physiognomy, such as Callisthene major in the cerrado stricto sensu and Anadenanthera colubrina in the dry forest. Only 20% of the species were widely distributed across both physiognomies or, not often, restricted to the intermediary values of the soil gradient. General results indicate that contrasting soil traits between cerrado stricto sensu and dry forest produce a strongly spatially organized and sharp transition in terms of species distribution between these physiognomies.


Author(s):  
Gloria Yaneth Florez-Yepes ◽  
Alejandro Rincón ◽  
Vladimir Henao Céspedes ◽  
Juan Carlos Granobles Tores ◽  
Fredy Edimer Hoyos Velasco

In order to determine an index of the status of optimal water variables for biodiversity conservation in the Sonso Lagoon, the data obtained from 2004 to 2018 were used. To determine the index, a methodology based on a multivariate analysis of the physical-chemical water variables was used, as well as a correlation analysis for their delimitation. Subsequently, the definition of weights and the parameterization of the variables for the final construction of the index were made. As a result, it was found that the lagoon is in an adequate state with a value index of 0.65, with a highly vulnerable tendency to be in an acceptable state and go to a critical state, depending on the anthropic pressure it has. As a conclusion, it was obtained that variables such as dissolved oxygen, total phosphorus and electrical conductivity are determining factors in establishing the index.


Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 612
Author(s):  
Arkadiusz Dyjakon ◽  
Łukasz Sobol ◽  
Tomasz Noszczyk ◽  
Jakub Mitręga

A large portion of food loss and waste (FSL) is comprised of seeds and stones. Exotic fruits such as mangoes, lychees and avocados, in which the seeds account for a significant part of the weight and volume of the entire product, are most affected by this problem. The seeds contain a large quantity of polyphenols and essential nutrients, which makes them a good material for extraction. However, conventional extraction techniques are considered time-consuming, and therefore significantly limit their use on an industrial scale. An alternative method of managing the seeds may be their energy utilization. In this study, torrefaction was proposed as a method for the valorization of exotic fruit seeds (mango, lychee, avocado). Thus, the influence of torrefaction temperature (200–300 °C) on the physical-chemical properties of substrates was investigated. The obtained results revealed that, in relation to the unprocessed raw materials, the torreficates are characterized by improved hydrophobic properties (all materials are classified as extremely hydrophobic), higher heating value (at 300 °C the values increased from 17,789 to 24,842 kJ∙kg−1 for mango, from 18,582 to 26,513 kJ∙kg−1 for avocado, and from 18,584 to 25,241 kJ∙kg−1 for lychee), higher fixed carbon content (which changed from 7.87–15.38% to 20.74–32.47%), and significant mass loss, by 50–60%. However, as a side effect of thermal treatment, an increase in ash content (approx. 2–3 times but still less than in coal) was observed. Therefore, the torreficates may be competitive with coal. The possibility of using residues from the food processing sector as a substrate for energy purposes is important from the point of view of environment protection and is a part of the functioning of the circular economy.


2022 ◽  
Vol 8 (1) ◽  
pp. 43-49
Author(s):  
N. Alikhanova ◽  
E. Novruzov

Zosima absinthifolia is the only species of Zosima genus in Azerbaijan. The aim of this study was to determine the quantitative and qualitative determination of fatty acids in the fruits of the plant Zosima absinthifolia, which is widespread in Absheron, as well as to study its physicochemical and organoleptic properties, possible use in the pharmaceutical and food industries. The oil obtained from the fruits of the plant collected from the Absheron Peninsula (Bibiheybat) was analyzed by gas chromatography. The oil was obtained at 60 °C for 8 h by the extraction of the fruits in a Soxhlet extractor. The yield was 10.36%. Chromatographic analysis of the oil obtained from plant fruits allowed to determine 14 fatty acids. The main component of Z. absinthifolia fruit oil is oleic acid (74.36%). Small amounts of caprylic and palmitic acids were also found to be 8.9% and 5.39%, respectively. The lowest percentage is palmitinoleic acid (0.07%). Physico-chemical constants and organoleptic properties of Z. absinthifolia fruit oil were also analyzed and it was determined that the percentage of free fatty acids in our sample was 2.47%, the peroxide value 34.16 mg O/kg and the saponification number 200.23 mg KOH/g.


Water ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 239
Author(s):  
Jerzy M. Kupiec ◽  
Agnieszka Bednarek ◽  
Sebastian Szklarek ◽  
Joanna Mankiewicz-Boczek ◽  
Liliana Serwecińska ◽  
...  

The aim of this study was to assess the efficiency of the innovative SED-BIO system in limiting the inflow of pollutants to Jelonek Lake. The analyses were conducted in the Gniezno Lake District in Greater Poland (the western part of Poland). Physical and chemical analyses were conducted in the years 2016–2019. The results demonstrate that the system is highly effective in the reduction of such nutrients as nitrogen (NO3−—63%; NH4+—14.9%) and phosphorus (PO43−—19.3%). Although the presence of cyanobacteria was confirmed practically throughout the whole monitoring period of the system (2016), the specimens found in most samples were not toxigenic genotypes with a potential to produce microcystins. Microcystins (3 µg·L−1) were detected only once, immediately after the SED-BIO system had been installed in the river and pond, which demonstrates that this natural toxin was eliminated from the additional pool of contaminants that might be transported to Jelonek Lake.


Agronomy ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 191
Author(s):  
Jan Adriaan Reijneveld ◽  
Martijn Jasper van Oostrum ◽  
Karst Michiel Brolsma ◽  
Dale Fletcher ◽  
Oene Oenema

Conventional soil tests are commonly used to assess single soil characteristics. Thus, many different tests are needed for a full soil fertility/soil quality assessment, which is laborious and expensive. New broad-spectrum soil tests offer the potential to assess many soil characteristics quickly, but often face challenges with calibration, validation, and acceptance in practice. Here, we describe the results of a 20 year research program aimed at overcoming the aforementioned challenges. A three-step approach was applied: (1) selecting and establishing two contrasting rapid broad-spectrum soil tests, (2) relating the results of these new tests to the results of conventional soil tests for a wide variety of soils, and (3) validating the results of the new soil tests through field trials and communicating the results. We selected Near Infrared Spectroscopy (NIRS) and multi-nutrient 0.01 M CaCl2 extraction (1:10 soil to solution ratio; w/v) as broad-spectrum techniques. NIRS was extensively calibrated and validated for the physical, chemical, and biological characteristics of soil. The CaCl2 extraction technique was extensively calibrated and validated for ‘plant available’ nutrients, often in combination with the results of NIRS. The results indicate that the accuracy of NIRS determinations is high for SOM, clay, SOC, ECEC, Ca-CEC, N-total, sand, and inorganic-C (R2 ≥ 0.95) and good for pH, Mg-CEC, and S-total (R2 ≥ 0.90). The combination of the CaCl2 extraction technique and NIRS gave results that related well (R2 > 0.80) to the results of conventional soil tests for P, K, Mg, Na, Mn, Cu, Co, and pH. In conclusion, the three-step approach has revolutionized soil testing in The Netherlands. These two broad-spectrum soil tests have improved soil testing; have contributed to increased insights into the physical, chemical, and biological characteristics of soil; and have thereby led to more sustainable soil management and cropping systems.


Author(s):  
Ömer Ertuğrul ◽  
Melih Yılar ◽  
Hakan Kır ◽  
Ceren Kömekçi

2022 ◽  
Vol 43 (1) ◽  
pp. 7-24
Author(s):  
Iris Mariane da Silva Martins ◽  
◽  
Tatiane Carla Silva ◽  
Maria Julia Betiolo Troleis ◽  
Paulino Taveira de Souza ◽  
...  

Effects of soil attributes using the geostatistical tool improves the interpretation of specific soil management. Thus, this study aimed to evaluate the physical, chemical, and microbiological properties of a Typical Haplustox (Oxisol), identifying those with the best linear and spatial correlation with eucalyptus (Eucalyptus spp.) vegetative growth. The experiment was conducted at the Teaching, Research, and Extension Farm (FEPE) of the Universidade Estadual Paulista (UNESP), Campus of Ilha Solteira. Thirty-five points spaced 13 meters apart were demarcated for analysis, which were distributed in 5 rows of 7 points each. From each point, 2 soil samples were collected from the 0-10 cm depth layer. The physical, chemical, and microbiological soil properties evaluated were: sand, silt, and clay contents; penetration resistance (PR), gravimetric moisture (GM), real density (RD), microbial biomass carbon (MBC), respirometry (CO2-C), metabolic quotient (qCO2), organic matter content (OM), and hydrogenionic potential (pH). The eucalyptus attributes assessed were: plant height (PH) and circumference at breast height (CBH). Each attribute was analyzed by descriptive statistics using the SAS software. Data frequency distribution was verified by the Shapiro Wilk method, and geospatial changes were analyzed by the GS+ software. The soil property that best explained the variability in eucalyptus dendrometric attributes was real density (RD). Except for RD, all properties did not show spatial dependence (i.e., pure nugget effect), which significantly represents eucalyptus vegetative performance.


2022 ◽  
Vol 43 (1) ◽  
pp. 415-430
Author(s):  
Natieli Inácio Fernandes ◽  
◽  
Claucia Aparecida Honorato da Silva ◽  
Gabriela Cristina Ferreira Bueno ◽  
Maria Luiza Rodrigues de Souza ◽  
...  

The aim of this study was to develop methodologies to obtain fish protein concentrates from tambacu filleting residues, characterize their physical-chemical composition and evaluate their sensory profile. Concentrates were prepared by one of three methodologies: cooking of the raw material and subsequent drying (FPC1); cooking, drying, lipid removal with ethanol at 70 °C and final drying (FPC2); and three washing steps of the raw material with ethanol at 70 °C and drying (FPC3). FPC2 had a lower final yield (15.5%) and chroma a* (1.77) and chroma b* values (14.12) but higher moisture (5.22%) and protein content (80.39%) and luminosity (74.97), in addition to having the weakest fish taste compared to FPC1 and FPC3. FPC1 had the strongest odour, darkest colour, and strongest fish taste compared to FPC2 and FPC3. Ash, pH values, and water activity were not different between the concentrates. It is concluded that the methodology where lipid removal steps are carried out after cooking and drying (FPC2) is more effective for the removal of lipids and deodorization of tambacu protein concentrate.


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