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Peatlands, known for their ability to retain and immobilize heavy metals due to unique waterlogged conditions and organic matter, face challenges when subjected to disturbances such as land use changes. These disruptions alter the organic matter, redox potential, and pH of the peatsoil, potentially influencing the migration, mobilization, and increased availability of stored heavy metals. Peatsoil samples from various peatland use types (improved and semi-natural grassland, forest, industrial cutaway bog) were collected to assess the human health and ecological risk associated with heavy metals (Cd, Cu, Hg, Pb, and Zn) in Co-Offaly, Ireland. Results reveal variations in heavy metal concentrations across peatland use types, with Cd, Hg, and Pb in improved and semi-natural grassland peatsoils exceeding the World Health Organization (WHO) permissible safety limits. Contamination factors (CF) were higher in improved grassland, especially for Cd and Pb, exceeding one. Hakanson potential ecological risk assessment indicates acceptable overall risk levels, though variations exist between improved grassland, unimproved grassland, forest, and industrial cutaway bog. Combined exposure routes (dermal, ingestion and inhalation routes) to all heavy metals do not exceed safe exposure levels (indicating low non-carcinogenic risks. However, the cancer risk (CR) exceeds acceptable thresholds across all use types, with higher CR in improved grassland, especially for children. Overall, the findings emphasize the need for careful consideration of heavy metal risks associated with land use changes in peatlands, particularly in the improved grassland areas.
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Many of the world's soils are experiencing degradation at an alarming rate. Climate change and some agricultural management practices, such as tillage and excessive use of chemicals, have all contributed to the degradation of soil fertility. Arbuscular Mycorrhizal Fungi (AMFs) contribute to the improvement of soil fertility. Here, a short review focusing on the role of AMF in improving soil fertility is presented. The aim of this review was to explore the role of AMF in improving the chemical, physical, and biological properties of the soil. We highlight some beneficial effects of AMF on soil carbon sequestration, nutrient contents, microbial activities, and soil structure. AMF has a positive impact on the soil by producing organic acids and glomalin, which protect from soil erosion, chelate heavy metals, improve carbon sequestration, and stabilize soil macro-aggregation. AMF also recruits bacteria that produce alkaline phosphatase, a mineralization soil enzyme associated with organic phosphorus availability. Moreover, AMFs influence the composition, diversity, and activity of microbial communities in the soil through mechanisms of antagonism or cooperation. All of these AMF activities contribute to improve soil fertility. Knowledge gaps are identified and discussed in the context of future research in this review. This will help us better understand AMF, stimulate further research, and help in sustaining the soil fertility.
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OBJECTIVES: The low fertility of highly weathered soils has been a major problem for resource-constrained smallholder farmers. In central Uganda, smallholder farmers have been collecting termite mound soils anywhere around the termite mound to improve their soil fertility. However, no studies have been conducted on which sections of the termite mounds consist of high soil nutrients. This study was conducted to assess selected major soil essential plant nutrients of soils collected from the top of the mound (TPMS), and the basal part of the mound (BPMS). The surrounding soil samples were collected from five, fifteen, and thirty meters away from the mound (TMSS1, TMSS2, and TMSS3 respectively), covering ten termite mounds in five different maize fields in central Uganda. RESULTS: TPMS and BPMS had significant (P-value < 0.05) higher N, P, K, OC, Ca and Mg levels than TMSS1, TMSS2, and TMSS3. However, OC levels in BPMS was higher than TPMS. On the whole, termite mounds are beneficial as a source for essential plant nutrients. It will be best if smallholder farmers could collect the termite mound soils from the top and the basal part of the mound to improve the fertility of their soil.
Asunto(s)
Isópteros , Suelo , Animales , Granjas , Microbiología del Suelo , UgandaRESUMEN
A study on the growth and reproductive performance of two rabbit breeds was undertaken. Data on 588 kits and 97 does of California White and 574 kits and 90 does of New Zealand White rabbits reared under hot and humid environment in Ghana were taken. The reproductive performance of the two breeds, in terms of litter size at birth and weaning, litter weight at birth and weaning, kindling interval, age at sexual maturity, and gestation length as influenced by breed, season of kindling (rainy and dry), year of kindling (2005-2012), and parity (first to sixth and over) were determined. The performance of California White in terms of litter size at birth, at weaning, kit weight at birth, and age at first kindling was 5.9 ± 0.2, 4.6 ± 0.1, 54.7 ± 0.4 g, and 159.8 ± 0.2 days, respectively. That of New Zealand White was 5.9 ± 0.1, 5.1 ± 0.1, 55.2 ± 1.0 g, and 159.9 ± 0.2 days, respectively. The results obtained also showed a significant breed effects on kit weight at birth, litter weight at weaning, and mortality; whereas no significant differences (p > 0.05) were observed between the two breeds regarding the other traits measured. Parity had significant effects (p < 0.05) on all the growth and reproductive parameters measured with the exception of age at first kindling. Year of kindling also had significant effect on litter weight at birth, kit weight at birth, and at weaning (p < 0.05) but did not have any significant effect on the age at sexual maturity and mortality. Season also had significant (p < 0.05) effects on kit weight at birth, gestation length, kindling interval, and mortality with better performance experienced during the rainy season.
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Crianza de Animales Domésticos/métodos , Cruzamiento/métodos , Tamaño de la Camada , Reproducción/fisiología , Animales , Peso Corporal , Femenino , Ghana , Modelos Lineales , Paridad , Embarazo , Conejos , Estaciones del Año , Especificidad de la Especie , DesteteRESUMEN
A study was conducted to assess the effect of non-genetic factors on the reproductive performance of Sanga and Friesian × Sanga crossbred dairy cattle kept at Amrahia Dairy Farm, Ghana. Records on 66 crossbred Friesian × Sanga and 105 purebred Sanga cattle from 2005 to 2012 were used. The effect of sex of calf (male or female), season of calving (major, minor and dry), year of calving (2005-2012) and parity (first to third) on birthweight, calving interval and age at first calving were determined. The data were analyzed using the general linear model procedures of GenStat (Discovery Edition). The effect of parity of dam, year of calving, season of calving and sex of calf were considered as fixed effects for evaluating the different reproductive traits. Data on calving and conception rates over the period were 74.3 and 76.1%, respectively. The overall mean values for birthweight, age at first calving and calving interval obtained were 23.9 ± 1.5 and 22.8 ± 1.4 kg, 38.8 ± 2.5 and 40.2 ± 2.4 months and 390.8 ± 12.5 and 413.6 ± 12.1 days for the crossbred and Sanga, respectively. It was observed that all the major determinants of reproductive performance studied apart from birthweight were significantly influenced by year of birth, parity, season of calving and sex.