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111.
Joana Garrido Nogueira Amílcar Teixeira Simone Varandas Manuel Lopes-Lima Ronaldo Sousa 《水产资源保护:海洋与淡水生态系统》2021,31(3):520-530
- Freshwater ecosystems are essential to human well-being and most have high biodiversity. However, this biodiversity has been suffering severe declines owing to the expansion of human activities. Protected areas (PAs) are essential for biodiversity conservation and have proved to be successful in stopping species extirpation if managed properly. Unfortunately, they are usually focused on terrestrial biodiversity, leaving freshwater ecosystems aside.
- The main goal of this study was to determine the influence of a PA (Montesinho Natural Park (MNP), Portugal) on freshwater biodiversity. Aquatic macroinvertebrates and fishes were surveyed, and biodiversity (richness, abundance, Shannon-Wiener diversity, and Pielou's evenness) and water quality (IASPT) indices were calculated inside, at the periphery and outside the MNP.
- Results showed that the PA does not affect positively either water quality or the two faunal groups monitored. Macroinvertebrate communities were not influenced by the PA; however, the abundance of pearl mussel Margaritifera margaritifera was significantly higher and size was significantly lower inside the MNP. The richness and abundance of fish communities were significantly higher outside the MNP, except for trout Salmo trutta abundance which was higher inside the MNP.
- Given these results, the MNP does not guarantee the safeguard of overall aquatic biodiversity and habitats and we propose an extension of MNP to downstream areas in order to increase the number of species (mostly cyprinids) under legal protection. This work demonstrates that terrestrial PA planning and management should also consider aquatic biodiversity to achieve successful conservation.
112.
Ricardo Sousa Paulo Henriques Joana Vasconcelos Ana Rita Pinto Joo Delgado Rodrigo Riera 《水产资源保护:海洋与淡水生态系统》2020,30(4):717-729
- Limpets are one of the most successful intertidal algal grazers in the north‐eastern Atlantic. They provide valuable ecosystem services, playing a pivotal role in maintaining rocky shore ecological balance and have an important economic value, being subject to high levels of exploitation in several oceanic archipelagos. Limpets represent one of the most profitable economic activities of small‐scale fisheries in the Madeira archipelago. However, limpets are extremely vulnerable to anthropogenic impacts, such as overharvesting, habitat fragmentation, and pollution.
- The protection effects and the effectiveness of marine protected areas (MPAs) on the population dynamics of two historically highly exploited limpet species, Patella aspera and Patella candei, were analysed through a comparative study of size, reproduction, and biomass in the Madeira archipelago.
- The effects of protection from MPAs on limpet populations resulted in a differential increase on size at first maturity, shell size, and capture per unit effort according to the degree of protection.
- Old and enforced MPAs showed the best‐preserved limpet populations in the study area, and both variables (age and enforcement) best explained the observed variability among the MPAs studied.
- A thorough and multidisciplinary study is necessary to obtain a reliable picture of commercial stocks of the two targeted species (P. aspera and P. candei). Genetic analysis and studies on the food source of limpets may shed light to develop integrative conservation strategies.
113.
Joana Vieira Sergio Rossi Filipe Campelo Cristina Nabais 《European Journal of Forest Research》2014,133(1):41-50
Neighboring trees growing under identical environmental conditions can exhibit different dynamics and periods of growth. Despite the recent advances in cambial biology, the exogenous and endogenous factors generating asynchronous xylem growths still remain undetermined. This study investigated timings and duration of xylem formation in maritime pine (Pinus pinaster Ait.) from an even-aged plantation in Portugal growing under Mediterranean climate. Cambial phenology and stem diameter were monitored weekly, from March to December 2010, on two classes of trees divided according to the tree ring widths of the last 15 years, but similar age and size: fast- and slow-growing trees. We tested the hypothesis that differences in tree ring widths result from cell production which in turn affects timings of xylogenesis and that the bimodal growth pattern, typical of the Mediterranean, originates from a double reactivation of the cambium: in spring and autumn. Cambial activity started earlier and ended later in fast-growing trees, confirming that cell production is a key factor determining the duration of xylogenesis. Intra-annual variations in stem diameter recorded by band dendrometers revealed two peaks of increment occurring in spring and late summer. However, the number of cambial cells did not increase in late summer, which suggested that the second peak of increment was caused by stem rehydration, rather than by a reactivation of cell division. These results demonstrated that the variability in the timings of xylem phenology observed among trees of the same age and size and growing under similar environmental conditions was closely related to cell production and not to age or size per se. 相似文献
114.
Tiago H. Silva Joana Moreira-Silva Ana L. P. Marques Alberta Domingues Yves Bayon Rui L. Reis 《Marine drugs》2014,12(12):5881-5901
Collagens are the most abundant high molecular weight proteins in both invertebrate and vertebrate organisms, including mammals, and possess mainly a structural role, existing different types according with their specific organization in distinct tissues. From this, they have been elected as one of the key biological materials in tissue regeneration approaches. Also, industry is constantly searching for new natural sources of collagen and upgraded methodologies for their production. The most common sources are from bovine and porcine origin, but other ways are making their route, such as recombinant production, but also extraction from marine organisms like fish. Different organisms have been proposed and explored for collagen extraction, allowing the sustainable production of different types of collagens, with properties depending on the kind of organism (and their natural environment) and extraction methodology. Such variety of collagen properties has been further investigated in different ways to render a wide range of applications. The present review aims to shed some light on the contribution of marine collagens for the scientific and technological development of this sector, stressing the opportunities and challenges that they are and most probably will be facing to assume a role as an alternative source for industrial exploitation. 相似文献
115.
116.
Gerardo Ojeda Joana Patrício Stefania Mattana Abilio J. F. N. Sobral 《Journal of Soils and Sediments》2016,16(10):2482-2491
Purpose
Biochar is a carbon-rich product, able to enhance soil fertility and mitigate CO2 emissions. While biochar effects on agriculture are becoming known, its impact elsewhere, e.g., on estuarine ecosystems, has yet to be assessed. The main aim of the present study was to determine the effect of biochar on sediment–water retention, CO2 emissions from sedimentary organic carbon decomposition, sediment pH and electrical conductivity, in aerobic conditions similar to those observed at low tide.Materials and methods
Sediments from the Mondego Estuary (Portugal) were mixed with pine gasification biochar at different doses (5, 10, 14 %) and immersed in water with different salinity values (15, 25, 30) for 96 h. The influence of biochar on water retention, the residence time of water and CO2 emissions between ?0.75 and ?1.5 MPa, total organic carbon, pH and electrical conductivity (EC) were determined. Carbon chemical composition and polycyclic aromatic hydrocarbon (PAH) concentrations were determined in sediments and biochar. Differences between biochar treatments after immersion in different water salinities were analysed using the Kruskal–Wallis test.Results and discussion
Results showed that biochar was able to (a) increase sediment–water content in terms of quantity and residence time, (b) decrease CO2 emissions, but only with a specific soil–water content and at the highest biochar dose, (c) increase sediment pH at all biochar doses and (d) increase sediment EC at the highest biochar dose. In contrast, the percentage of carbon mineralised was not modified. Biochar carbon was rich in PAHs and less decomposable than sedimentary carbon. The increments observed in sediment pH and EC were unable to change sediment alkaline or saline status according to standard classifications.Conclusions
Our results suggest that the remarkable water adsorption capacity of biochar–sediment mixtures may be considered the main factor in regulating CO2 emission rates from sediments, together with high PAH concentrations, which probably restrain the organic matter decomposition process.117.
Günter Gunkel Jan Kosmol Maria Sobral Hendryk Rohn Suzana Montenegro Joana Aureliano 《Water, air, and soil pollution》2007,180(1-4):261-269
The Ipojuca river, a river in Northeast Brazil extending from west to east, is situated in the semiarid interior and rainy coastal zone of Pernambuco state. The river basin covers an area of 3,514 km2, with a total river length of 215 km. The water flow regime is characterized by the annual change from dry to rainy season as well as periodically occurring dry cycles. Mean flow rates vary between 2 and 35 m3 s?1. The dominant impacts on water quality of the river are domestic sewage input in the upper catchment and sugar cane cultivation and processing in the lower catchment. Long-term monitoring data used to demonstrate the impact of sewage discharge on the river’s self-purification capacity indicated a severe change to the worse in the lower course. One reason is the use of stillage (wastewater from cane processing) for fertilization and irrigation (fertigation). Pathways of contamination have been identified by evaluating cultivation and processing techniques of a bio-alcohol factory with annexed sugar cane cultivation. The river’s main ecological problems are water heating, acidification, increased turbidity, oxygen imbalance, and increased coliform bacteria levels. Precipitation-related wash-off and wash-out causes significant contamination within one to two days after rainfall. The increase in coliform bacteria is a consequence of secondary contamination. To determine the impact of the sugar cane industry on the river, the Brazilian bio-alcohol program must be subject to a critical evaluation. Environmentally friendly sugar cane cultivation methods need to be developed, and sugar cane factories must use waste-reducing technologies and water cycling processes in order to protect the region’s water resources. 相似文献
118.
Quantification of tocopherols and tocotrienols in portuguese olive oils using HPLC with three different detection systems 总被引：2，自引：0，他引：2
Cunha SC Amaral JS Fernandes JO Oliveira MB 《Journal of agricultural and food chemistry》2006,54(9):3351-3356
Three different HPLC detection systems were compared for the determination of tocopherols and tocotrienols in olive oil: fluorescence and diode array connected in series, ultraviolet, and evaporative light scattering. The best results were obtained with the fluorescence detector, which was successfully applied in the quantification of tocopherols and tocotrienols in 18 samples of Portuguese olive oils. To support the validity of the method, the parameters evaluated were linearity, detection limits, repeatability, and recovery. All of the studied samples showed similar qualitative profiles with six identified compounds: alpha-T, beta-T, gamma-T, delta-T, alpha-T3, and gamma-T3. Alpha-tocopherol (alpha-T) was the main vitamin E isomer in all samples ranging from 93 to 260 mg/kg. The total tocopherols and tocotrienols ranged from 100 to 270 mg/kg. Geographic origin did not seem to influence the tocopherol and tocotrienol composition of the olive oils under evaluation. 相似文献
119.
Joana R. Lérias Lorenzo E. Hernández-Castellano Antonio Morales-delaNuez Susana S. Araújo Noemí Castro Anastasio Argüello Juan Capote André M. Almeida 《Tropical animal health and production》2013,45(8):1731-1736
Seasonal weight loss (SWL), caused by poor quality pastures during the dry season, is the major limitation to animal production in the tropics. One of the ways to counter this problem is to breed animals that show tolerance to SWL. The objective of this study was to understand the effect of feed restriction in milk production and live weight (LW) evolution in two goat breeds, with different levels of adaptation to nutritional stress: the Majorera (considered to be tolerant) and the Palmera (considered to be susceptible). A total of ten animals per breed were used. Animals were divided in four groups (two for each breed): a restricted group (restricted diet) and a control group. LW and milk yield parameters were recorded through a trial that lasted 23 days in total. Overall, there were no significant differences between both restricted groups, regarding neither LW nor milk yield reductions (LW reduction 13 % and milk yield reduction of 87 % for both restricted groups). In what concerns control groups, there were no significant differences between breeds, thought there were different increments at the end of the trial for both breeds regarding LW (6 and 4 %, for Majorera and Palmera, respectively) and milk yield (28 and 8 %, respectively for Majorera and Palmera). The lack of statistically significant differences between Palmera and Majorera LW and milk yields in restricted groups may be due to the fact that the controlled trial does not replicate harsh field conditions, in which Majorera would excel, and the stress induced by those differences. 相似文献
120.
MUC1 expression in canine malignant mammary tumours and relationship to clinicopathological features
de Oliveira JT Pinho SS de Matos AJ Hespanhol V Reis CA Gärtner F 《Veterinary journal (London, England : 1997)》2009,182(3):491-493
Mucin-1 (MUC1) is over-expressed in human breast carcinomas and is linked to a poorer prognosis. In this study, MUC1 expression in 32 spontaneous canine malignant mammary tumours was characterised in relation to histological type, mode of growth, grade, lymph node metastases and distant metastases. All tumours exhibited immunostaining for MUC1. In the normal canine mammary gland, MUC1 was expressed mainly in the apical cellular membrane, while in carcinomas MUC1 was detected in the cytoplasm only (56.3%) or in the cytoplasm with membrane accentuation (43.7%). There was a significant association between development of distant metastases and MUC1 over-expression (P=0.03), but no association with histological type, histological grade, mode of growth or lymph node metastasis. 相似文献