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The hydrographic eastern Mediterranean Basin of Turkey is a drought sensitive area. The basin is an important agricultural area and it is necessary to determine the extent of extreme regional climatic changes as they occur in this basin. Pearson's correlation coefficient was used to show the correlation between standardized precipitation index(SPI) and standardized streamflow index(SSI) values on different time scales. Data from five meteorological stations and seven stream gauging stations in four sub-basins of the eastern Mediterranean Basin were analyzed over the period from 1967 to 2017. The correlation between SSI and SPI indicated that in response to meteorological drought, hydrological drought experiences a one-year delay then occurs in the following year. This is more evident at all stations from the mid-1990 s. The main factor causing hydrological drought is prolonged low precipitation or the presence of a particularly dry year. Results showed that over a long period(12 months), hydrological drought is longer and more severe in the upper part than the lower part of the sub-basins. According to SPI-12 values, an uninterrupted drought period is observed from 2002–2003 to 2008–2009. Results indicated that among the drought events, moderate drought is the most common on all timescales in all sub-basins during the past 51 years. Long-term dry periods with moderate and severe droughts are observed for up to 10 years or more since the late 1990 s, especially in the upper part of the sub-basins. As precipitation increases in late autumn and early winter, the stream flow also increases and thus the highest and most positive correlation values(0.26–0.54) are found in January. Correlation values(ranging between –0.11 and –0.01) are weaker and negative in summer and autumn due to low rainfall. This is more evident at all stations in September. The relation between hydrological and meteorological droughts is more evident, with the correlation values above 0.50 on longer timescales(12-and 24-months). The results presented in this study allow an understanding of the characteristics of drought events and are instructive for overcoming drought. This will facilitate the development of strategies for the appropriate management of water resources in the eastern Mediterranean Basin, which has a high agricultural potential.  相似文献   
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Stress load on harvest‐size common carp (Cyprinus carpio L.) just before harvest, during harvest and during the post‐harvest storage were assessed using haematological and biochemical indices. The study was carried out at the 60 ha Dřemliny pond for 28, 7 and 1 day before harvest, during 3‐day harvest and after a 28‐day post‐harvest period. Indices monitored included the relative spleen weight (SSI), erythrocyte count (Er), haemoglobin levels (Hb), haematocrit (PCV), MCV, MCH, MCHC, leucocrit (Bc), differential leucocyte count (leucogram), blood plasma cortisol, glucose, total proteins (TP), cholesterol and chloride. During harvest, a significant decrease of SSI (P<0.05; P<0.01), increase of PCV (P<0.01), decrease of Bc (P<0.01, P<0.05), lymphopenia (P<0.05) and neutrophilia (P<0.01) were observed. A significant increase in the levels of blood plasma cortisol was found 1 day before harvest (P<0.05) due to draining off the pond before harvest itself, hyperglycaemia was observed 1 day before harvest (P<0.05) and during harvest (P<0.01); a decrease, on the other hand, was found in cholesterol and chloride levels (P<0.01). The relationships between oxygen content in water and SSI and MCHC were positive (P>0.05) and between oxygen and glucose were negative (P>0.01). A 28‐day post‐harvest storage returned the indices investigated back to physiological interval of values. Persistently lower levels of Bc, lymphopenia, neutrophilia and lower TP concentrations are indicative of deepening immunosuppression during the post‐harvest storage period. Changes of haematological and biochemical indices during harvest in relation to hypoxia, fish handling and higher stocking rates are also discussed.  相似文献   
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对芽苗期6个南瓜砧木品种进行了不同Ca(NO_3_)2浓度(0,80,120.160,200,240 mmol/L)胁迫处理,7 d后调查不同处理的盐胁迫指数.结果表明,6个南瓜砧木品种在不同Ca(NO_3)_2浓度处理下存在明显的耐盐性差异,其中120 mmol/LCa(NO_3)_2可以作为芽苗期瓜耐盐筛选浓度;以Ca(NO_3)_2浓度为120 mmol/L作基准,对18个南瓜自交系进行了芽苗期耐盐分析.结果显示,自交系063-2和自交系045-3的耐盐性较强,有较好的利用价值.  相似文献   
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就业体检是否可以应用基因检测,值得探讨。基因检测的应用,应遵循平等和非歧视、知情同意、比例性以及利益平衡原则。从域外的基因法制来看,对就业体检应用基因检测,实行绝对禁止或相对禁止的法律规制。在完善和建构我国的相关制度方面,不仅应依法确立就业体检之基因检测模式,而且要完善和规范就业体检的操作规程以及基因检测的实施程序。  相似文献   
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