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1.
  • 1. Forest restoration through silviculture (gardening) programs revives productivity, biodiversity, and stability. As in silviculture approaches, the coral ‘gardening’ strategy is based on a two‐step protocol.
  • 2. The first step deals with the establishment of in situ and/or ex situ coral nurseries in which corals are farmed (originating from two types of source material: asexual [ramets, nubbins], and sexual [planula larvae, spat] recruits).
  • 3. The second is the reef rehabilitation step, where maricultured colonies are transplanted into degraded sites.
  • 4. We compare here the rationale of forest restoration to coral reef ecosystem restoration by evaluating major key criteria. As in silviculture programs, a sustainable mariculture operation that focuses on the prime structural component of the reef (‘gardening’ with corals) may promote the persistence of threatened coral populations, as well as that of other reef taxa, thus maintaining genetic diversity. In chronically degrading reef sites this may facilitate a halt in biodiversity depletion.
  • 5. Within the current theoretical framework of ecosystem restoration, the recovery of biodiversity indices is considered a core element since a rich species diversity provides higher ecosystem resilience to disturbances.
  • 6. The gardening measure may also be implemented worldwide, eliminating the need to extract existing colonies for transplantation operations. At degraded reef sites, the coral gardening strategy can assist in managing human and non‐human stakeholders' requirements as is done in forest management.
Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
2.
Slurries of anoxic paddy soil were either freshly prepared or were partially depleted in endogenous electron donors by prolonged incubation under anaerobic conditions. Endogenous NO 3 was reduced within 4 h, followed by reduction of Fe3+ and SO 4 2– , and later by production of CH4. Addition of NO 3 slightly inhibited the production of Fe2+ in the depleted but not in the fresh paddy soil. Inhibition was overcome by the addition of H2, acetate, or a mixture of fatty acids (and other compounds), indicating that these compounds served as electron donors for the bacteria reducing NO 3 and/or ferric iron. Addition on NO 3 also inhibited the reduction of SO 4 2– in the depleted paddy soil. This inhibition was only overcome by H2, but not by acetate or a mixture of compounds, indicating that H2 was the predominant electron donor for the bacteria involved in NO 3 and/or SO 4 2– reduction. SO 4 2– reduction was also inhibited by exogenous Fe3+, but only in the depleted paddy soil. This inhibition was overcome by either H2, acetate, or a mixture of compounds, suggesting that they served as electron donors for reduction of Fe3+ and/or SO 4 2+ . CH4 production was inhibited by NO 3 both in depleted and in fresh paddy soil. Fe3+ and SO 4 2– also inhibited methanogenesis, but the inhibition was stronger in the depleted than in the fresh paddy soil. Inhibition of CH4 production was paralleled by a decrease in the steady state concentration of H2 to a level which provided a free enthalpy of less than G=–17 kJ mol-1 CH4 compared to more than G=–32 kJ mol-1 CH4 in the control. The results indicate that in the presence of exogenous fe3+ or SO 4 2+ , methanogenic bacteria were outcompeted for H2 by bacteria reducing Fe3+ or SO 4 2+ .Deceased on 27 December 1992  相似文献   
3.
In this article we have presented genetic predispositions and the influence of numerous factors that occur during cattle fattening, transport and holding in slaughter plants, on their welfare and subsequently on the occurrence of defective meat, known in the literature as DFD (Dark, Firm, Dry) meat. Such meat is unwillingly bought by contemporary consumers because of its consistency and processing plants cannot intend it for production of durable processed meat due to its compliance to decay. To a great extent the occurrence of this meat defect is caused by people as a result of ignorance and incompliance of cattle welfare. It should also be remarked that there is a rising number of consumers interested in the place of origin of cattle and the way it was treated.  相似文献   
4.
5.
The potential risk of pesticides to cause harm to humans and other organisms even at trace levels calls for sensitive and accurate analytical techniques for their simultaneous qualitative and quantitative determinations. In this study, a sensitive binary dispersive liquid-liquid microextraction (B-DLLME) strategy was developed for the simultaneous determination of phorate and oxyfluorfen by gas chromatography mass spectrometry after extraction/preconcentration from aqueous solution. An experimental design was used to optimize parameters of the B-DLLME method to obtain maximum outcome. Under the optimum conditions of B-DLLME, the limit of detection (LOD) for phorate and oxyfluorfen were found to be 0.41 μg L?1 and 0.54 μg L?1, respectively. The detection limits correlate to about 37 and 73 folds enhancement in detection powers when compared to direct GC-MS determination of phorate and oxyfluorfen, respectively. In order to find out the applicability of developed method to real samples, recovery tests were performed for 20 μg L?1 of phorate and oxyfluorfen spiked in well water samples. Percent recovery values were found to be 94.5% for phorate and 101.9% for oxyfluorfen.  相似文献   
6.
Green algae (Chorella pyrenoidosa) were grown in iron‐deficient and normal iron supplied nutrient solution and treated with 1 uM gallium. Treatment with gallium enhanced the growth rate and chlorophyll content of algae cultures. Significant changes were recorded in individual photosynthetic pigment composition of treated cultures. In both iron‐deficient and normal iron supplied cultures, gallium treatment enhanced peroxidase enzyme activity. Partially purified peroxidase showed different kinetic properties in the samples treated with gallium. An iron‐gallium interaction is proposed that affects chlorophyll metabolism and peroxidase activity in green algae.  相似文献   
7.
Amoxicillin is used in the treatment and prevention of a wide range of diseases in poultry breeding. However, its short half‐life and low bioavailability restrict its clinical application in these species. Entrapment of drugs into polymeric nanoparticles (nps) presents a means to improve gastrointestinal absorption and oral bioavailability of drugs. This study was aimed to overcome limitation of amoxicillin use in poultry breeding. Amoxicillin was loaded into sodium alginate‐polyvinyl alcohol (NaAlg‐PVA ) blend nps, and characterization of the prepared nps was performed. For pharmacokinetic study, commercial male broilers were used and comparative pharmacokinetics of free and nanoparticle form of amoxicillin were investigated. Twenty‐one broilers were divided into three groups. All groups received 10 mg/kg drug. Blood samples were collected, and drug plasma concentrations were determined by HPLC . The results demonstrated that the particle size, zeta potential, encapsulation efficiency, and loading capacity of the nps were 513.96 ± 19.46 nm, ?45.36 ± 1.35 mV , 43.66 ± 3.30, and 12.06 ± 0.83%, respectively. In vitro drug release exhibited a biphasic pattern with an initial burst release of 18% within 2 hr followed by a sustained release over 22 hr. The pharmacokinetic results showed that amoxicillin nps have higher bioavailability and longer plasma half‐life (<  .01) than free amoxicillin. These results indicate that amoxicillin nano formulation is suitable for oral administration in broilers.  相似文献   
8.
The purpose of the study was to investigate whether acute strenuous exercise (1600- to 2500-m race) would elicit an acute phase response (APR) in Standardbred trotters. Blood levels of several inflammatory markers [serum amyloid A (SAA), haptoglobin, fibrinogen, white blood cell count (WBC), and iron], muscle enzymes [creatinine kinase (CK) and aspartate transaminase (AST)], and hemoglobin were assessed in 58 Standardbred trotters before and after racing. Hemoglobin levels increased and iron levels decreased 12 to 14 h after racing and haptoglobin concentrations, white blood cell counts, and iron levels were decreased 2 and/or 7 d after racing. Concentrations of CK, AST, SAA, and fibrinogen were unaltered in response to racing.Acute strenuous exercise did not elicit an acute phase reaction. The observed acute increase in hemoglobin levels and decreases in haptoglobin and iron levels may have been caused by exercise-induced hemolysis, which indicates that horses might experience a condition similar to athlete’s anemia in humans. The pathogenesis and clinical implications of the hematological and blood-biochemical changes elicited by acute exercise in Standardbred trotters in the present study warrant further investigation.  相似文献   
9.
A Regional Soil Acidification Model (RESAM) has been developed to gain insight in long-term impacts of deposition scenarios on forest soils in The Netherlands. Model predictions of such large-scale environmental effects of acid deposition require extrapolation of site specific data to large geographical regions. The major aim of this study is to quantify the uncertainty in model response to a given deposition scenario, due to uncertainty and spatial variability in data. Furthermore, the uncertainty analysis was performed to determine which additional data will most likely improve the reliability of predictions. An efficient Monte Carlo technique was used in combination with regression analysis. The analysis was restricted to one forest soil ecosystem: a leptic podzol with Douglas fir, subject to a reducing deposition scenario. The investigated output variables were pH, Al/Ca ratio and NH4/K ratio in the root zone, which are generally used as indicators of forest soil acidification and of potential forest damage. Statistical analyses showed that in most cases the relation between the parameters and model output can be satisfactorily described by a linear regression model. The uncertainty contribution of various parameters depends on the considered output variable, soil compartment and time. The uncertainty, as measured by the coefficient of variation, appears to be high for the NH4/K and Al/Ca ratios, whereas it was relatively low for the pH. Results show that the uncertainty in the depositions of SOx, NOx, and NHx in a receptor area and the uncertainty in the parameters and variables determining the nitrogen and aluminium dynamics contribute most to the resulting uncertainty of the considered model output.  相似文献   
10.
Sixtyfour compacted morulae and blastocysts were bisected with a microscalpel. The majority of the demi-embryos (n = 122) were reinserted into separate zona pellucidae (ZP) before non-surgical transfer to 113 synchronized recipients, as singles (n = 98) (DE-S) or in pairs (n = 30) (DE-P). Thirty non-manipulated embryos (E) were transferred during the same period and served as controls. Pregnancies were diagnosed by rectal palpation 4-7 weeks after transfer. The pregnancy rates for DE-S, DE-P and E were 32%, 53% and 40%, respectively (P greater than 0.05). A substantial number of abortions were recorded between 50 and 250 days of pregnancy among the recipients with DE-S. The fetal survival rate for DE-S was reduced to 21% and significantly lower (p less than 0.05) than the survival rates of DE-P (43%) and E (40%). The quality of DE and the presence of ZP did not significantly influence the results. No conclusive reasons for the fetal loss could be found but different possibilities are discussed.  相似文献   
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