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1.
Soil protection for a sustainable future: options for a soil monitoring network for Ireland
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The increased recognition of the importance of soil is reflected in the UN Post‐2015 Development Agenda with sustainable development goals that directly and indirectly relate to soil quality and protection. Despite a lack of legally binding legislation for soil protection, the European Commission remains committed to the objective of soil protection. However, the achievement of a legally binding framework for soil protection relies on the implementation of a soil monitoring network (SMN) that can detect changes to soil quality over time. As beneficiaries do not pay for the provision of soil information, the options for soil monitoring are limited. The use of existing data sets should be considered first. Using Ireland as an example, this research explored the opportunities for a SMN for Ireland considering three existing national data sets. The options for a SMN are considered in terms of their spatial and stratified distribution, the parameters to be measured and an economic analysis of the options proposed. This research finds that for Ireland, either a 10 or a 16 km2 grid interval stratified by land use and drainage class offers the best potential in relation to the spatial distribution of existing data sets to reflect local data at a national level. With existing data, the stratified SIS data using the 16 km2 grid offers the best value for money, with baseline costs for analysis, excluding field costs, of between €706 481 and €2.8 million. Acknowledging the impossibility of measuring all parameters with ideal frequency, this study proposes a two‐tier system for optimized monitoring frequency. Parameters must anticipate future policy requirements. Finally, the implementation of a SMN must be accompanied by standardized methods, defined thresholds and action mandates to maintain soil quality within allowable limits. 相似文献
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上虞市海涂实验农场中心试验区的排水系统,能满足十年一遇的年最大24h降雨,两天内排出的要求。滨海盐土的地下水位高,农田基本建设除用浅、密的排水沟布置外,还应结合平整土地、发展灌溉以及适用的农、林技术等综合措施,才能达到治盐改土的效果。 相似文献
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N. J. Grünwald F. Workneh S. Hu A. H. C. van Bruggen 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(1):55-63
Testing of soil samples in greenhouse assays for suppressiveness to soilborne plant pathogens requires a considerable investment in time and effort as well as large numbers of soil samples. To make it possible to process large numbers of samples efficiently, we compared an in vitro growth assay with a damping-off assay using Pythium aphanidermatum as the test organism on tomato seedlings. The in vitro test compares the radial growth or relative growth of the fungus in soil to that in autoclaved soil and reflects suppressiveness of soils to the pathogen. We used soils from a field experiment that had been farmed either organically or conventionally and into which a cover crop (oats and vetch in mixture) had been incorporated 0, 10, 21, and 35 days previously. We obtained a significant, positive correlation between damping-off severities of tomato seedlings in damping-off assays and both relative and radial growth in vitro. In addition, radial and relative growth of P. aphanidermatum in the in vitro assay were positively correlated with several carbon and nitrogen variables measured for soil and incorporated debris. We did not find differences between the two farming systems for either growth measures of P. aphanidermatum or disease severities on tomato at different stages of cover crop decomposition. The in vitro assay shows potential for use with any fungus that exhibits rapid saprophytic growth, and is most suitable for routine application in suppressiveness testing. 相似文献
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Comparison of the pharmacokinetic profiles of two different amphotericin B formulations in healthy dogs
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This study was conducted to compare the pharmacokinetic profiles of conventional (Fungizone®) and liposomal amphotericin B (AmBisome®) formulations in order to predict their therapeutic properties, and evaluate their potential differences in veterinary treatment. For this purpose, twelve healthy mixed breed dogs received both drugs at a dose of 0.6 mg/kg by intravenous infusion over a 4‐min period in a total volume of 40 ml. Blood samples were collected at 0, 0.5, 1, 1.5, 2, 3, 4, 8, 12, 24, 48, 72 and 96 hr after dosing, and concentrations of drug in plasma were determined by high‐performance liquid chromatography (HPLC). Pharmacokinetics was described by a two‐compartment model. Although both formulations were administered at the same doses (0.6 mg/kg), the plasma pharmacokinetics of liposomal amphotericin B differed significantly from those of amphotericin B deoxycholate in healthy dogs (p < .05). Liposomal amphotericin B showed markedly higher peak plasma concentrations (approximately ninefold greater) and higher area under the plasma concentration curve values (approximately 14‐fold higher) compared to conventional formulation. It is concluded that AmBisome® reached higher plasma concentration and lower distribution volume and had a longer half‐life compared to Fungizone®, and therefore, AmBisome® is reported to be an appropriate and effective choice for the treatment of systemic mycotic infections in dogs. 相似文献
5.
随着国内城市化的推进,市政工程的给排水工程越发显得重要。传统的给排水施工技术已经无法满足城市发展要求,社会对给排水的施工质量提出了更高地要求。文章结合当前给排水施工管理现状,对给排水施工的施工管理各方面进行简要探析。 相似文献
6.
How to characterize ‘good’ and ‘greening’ in the EU Common Agricultural Policy (CAP): the case of clay soils in the Netherlands
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The change in the Common Agricultural Policy (CAP) of the European Union from product to producer support, including requirements for ‘good agricultural and environmental conditions’ and ‘greening’, is excellent. However, these requirements are now defined in rather general terms. Questions can be raised about suitable indicators, and there is a recognized need for effective management recommendations to support farmers in achieving the required ‘good’ conditions. These recommendations are bound to be quite different for different soils in different countries. A study of Dutch clay soils was based on a storyline describing current problems and management options for improvement, which were quantified using a soil–water–crop simulation model. Indicators were defined for agricultural conditions and suggestions made for the use of the model in a predictive mode to help farmers improve their soil management. Environmental conditions were judged by current environmental guidelines for water and air. When modelling, implicit assumptions that soils are homogeneous were shown to be unrealistic for these clay soils, requiring development of innovative methods and procedures, presenting a challenge for soil research. 相似文献
7.
Baris Guner Gulsum Selcuk Sevket Guclu Sultan Sengul Ismail Altun Serdal Dikmen Ahmet Gumen 《Reproduction in domestic animals》2021,56(9):1254-1260
The objective of the study was to compare the fertility after using sex-sorted or conventional semen either with oestrus detection (EST) or timed artificial insemination (TAI) in Holstein heifers. Holstein heifers were randomly assigned to one of the following treatments in a 2 × 2 factorial design. Heifers in the EST group were inseminated with sex-sorted (n = 114) or conventional semen (n = 100) after spontaneous or induced oestrus. Heifers in the TAI, subjected to the 5-day Cosynch+Progesterone protocol (GnRH+P4 insertion-5d-PGF2α+P4 removal-1d-PGF2α-2d-GnRH+TAI), were inseminated with sex-sorted (n = 113) or conventional semen (n = 88). Statistical analyses were performed using PROC GLIMMIX procedure of SAS 9.4 (SAS Institute Inc., Cary, NC). Overall P/AI was 60.7% for EST and 54.2% for TAI regardless of types of semen and 68.1% for conventional and 48.9% for sex-sorted semen regardless of insemination strategies. Fertility of heifers inseminated with either sex-sorted (53.5%; 44.2%) or conventional (69.0%; 67.0%) semen did not differ between EST and TAI respectively. Besides, the interaction between the semen type and the insemination strategy was not significant for P/AI. The embryonic loss was significantly greater with sex-sorted semen (17.1%) compared to conventional semen (1.6%). There was no sire effect with sex-sorted semen on P/AI (52.6% vs. 46.2%) and embryonic loss (16.4% vs. 18.0%). As expected, sex-sorted semen resulted in more female calves (89.8% vs. 51.6%) than conventional semen. Thus, sex-sorted semen can be used with 5-day Cosynch+Progesterone protocol to eliminate the inadequate oestrus detection and to increase female calves born in dairy heifers. 相似文献
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