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1.
The activity levels of succinate dehydrogenase (SDH) and glucose‐6‐phosphate dehydrogenase (G6PD) were assessed in various tissues of Cyprinus carpio var communis which had been exposed to lethal concentrations of group‐II pyrethroids (deltamethrin, cypermethrin, fenvalerate and fluvalinate) for a period of 72 h. The results indicated a steady decrease in SDH activity with a concomitant increase in G6PD activity. The decreased SDH activity indicated inhibition of SDH at mitochondrial level and the increased G6PD activity an enhancement of an alternative pathway of carbohydrate metabolism, viz the hexose monophosphate shunt (HMP) or pentose phosphate pathway as a biochemical adaptation to overcome the toxic stress. © 2001 Society of Chemical Industry  相似文献   
2.
Eelpouts (Zoarces viviparus), a viviparous fish, were sampled in Danish coastal waters during October and November 2001 and 2002, in ten different areas, which are receiving effluents from cities and industry to more or minor degree. The presence of gross abnormalities in eelpout broods has been suggested to be a useful biomarker of the impact of hazardous substances on fish reproduction in the marine environment as chronic exposure to various substances has the potential to induce severe developmental defects in fish embryos and larvae. Relatively high frequencies of female eelpouts (20–53) with elevated levels (>5) of larvae with developmental defects in the broods were found in four shallow fjords with effluents from larger cities and industry compared to areas. Deformations like spiral or bend shapes of the spinal axis, cranio-facial defects, eye lesions or loss of eyes were the dominating types. In some ofthe areas with the highest incidences of developmental defects, the adults had significantly enlarged livers, which may also be a possible effect caused by contaminant exposure. In two of the areas, relatively high frequencies of the broods contained larvae, which had died late but without any visible developmental defects. These two areas were affected by severe oxygen depletion prior to sampling time suggesting that examination of broods in the eelpout may include not only impact of hazardous substances but also effect of eutrophication-related problems on fish reproduction in the marine environment.  相似文献   
3.
逊别拉河自然保护区浮游植物群落结构特征的初步研究   总被引:1,自引:0,他引:1  
2010年9~10月,对逊别拉河自然保护区浮游植物群落结构进行了初步研究,并利用生物指数对逊别拉河自然保护区水质进行评价。结果表明,浮游植物共计8门50种,以硅藻为主,28种,占56.0%;绿藻次之,15种,占30.0%;蓝藻2种,占8.5%;隐藻、裸藻、甲藻、金藻、黄藻各1种,共占14.0%;优势种类及常见种全部为硅藻门种类:尖针杆藻Synedra acus、脆杆藻Fragilaria sp.、扭曲小环藻Cyclotella comta、缢缩异极藻Gomphonemaconstrictum、舟形藻Acicular sp.、简单舟形藻Navicula simples、羽文藻Pinnularia sp.、桥弯藻Cymbella sp.、箱形桥弯藻Cymbella cistula。浮游植物平均数量为183.47×104ind..L-1,硅藻的数量较多,134.12×104ind..L-1,占61.82%;生物量为4.3740mg.L-1,硅藻的生物量最高3.9354mg.L-1,占89.9%。采用多样性指数H'、J水质类型的评价标准对逊别拉河自然保护区水质进行评价,结果显示逊别拉河自然保护区H'均值为3.01,J均值为0.88,水域属于寡污-清洁型河流,为鱼类提供了良好的水域环境。  相似文献   
4.
通过比较生物指示与生物监测技术和仪器分析技术的分析过程及原理,结合北京市土壤中土壤脲酶与土壤重金属含量之间的相关关系的案例,及生物指示与生物监测技术在水生生态系统及大气污染研究中的应用状况,系统阐述了生物指示与生物监测技术研究的发展历程、研究前沿及发展方向.指出定量校正及不同学科与地区的科学团队的合作是生物指示与生物监测技术研究中需要克服的关键问题,并提出生物指示与生物监测技术研究的目标是整合不同学科的研究方向,为人类健康与环境安全的保护与预测提供技术支持.  相似文献   
5.
Abstract

The distribution of chromium, nickel, and cobalt in the plant species and soil of the Zn‐Pb‐Ag sulfide deposits of the Keban area in Turkey have been studied to determine both biogeochemical indicators and biomonitoring of environmental pollution. Plants, including Euphorbia, Verbascum, and Astragalus, and their associated soil samples were collected, and the roots and shoots of these plants together with soils were analyzed by inductively coupled plasma‐mass spectrometry (ICP‐MS). The three metal concentrations in the shoots of Euphorbia samples were found to be lower than in their roots, whereas the metal concentrations in shoots of Verbascum are higher than in their roots. Although the metal concentrations in soils were found to be lower than the permissible limits for agricultural purposes, the concentrations of these metals in different parts of some plants were observed at excessive/toxic levels. As a result, the roots of Euphorbia and the shoots of Verbascum and Astragalus can be used to biomonitor environmental contamination and as biogeochemical indicators.  相似文献   
6.
Biomonitoring of rivers is usually undertaken using information based on macroinvertebrate assemblages. However, exclusion of meiofauna (i.e. invertebrates less than 0.5?mm in size) when sorting benthic invertebrates can affect the estimation of densities and other biotic indices. In the present study, the effect of excluding the less than 0.5?mm fraction of invertebrates on estimation of benthic invertebrate indices was investigated in the Naro Moru River, Kenya. The Shannon–Wiener diversity index, Pielou’s evenness index, a multimetric index, Simpson’s diversity index, Margalef’s diversity index, mean invertebrate density, taxa richness, and Ephemeroptera, Plecoptera and Trichoptera (EPT) densities were determined. Only mean invertebrate and EPT densities differed significantly between the greater than 0.5?mm and total fractions. In conclusion, exclusion of meiofauna from invertebrate samples can affect the estimation of some stream invertebrate biotic indices.  相似文献   
7.
Agricultural expansion and intensification are having a huge impact on plant and arthropod diversity and abundance, affecting food availability for farmland birds. Difficult food access, in turn, can lead to immunosuppression and a higher incidence of parasites. In the studies designed to examine changes in the diet of birds and their parasites, metabarcoding is proving particularly useful. This technique requires mini-barcodes capable of amplifying the DNA of target organisms from fecal environmental DNA. To help to understand the impact of agricultural expansion on biodiversity, this study sought to design and identify mini-barcodes that might simultaneously assess diet and intestinal parasites from the feces of farmland birds. The capacity to identify diet and parasites of 2 existing and 3 newly developed mini-barcodes was tested “in silico” in relation to the behavior of a reference eukaryotic barcode. Among the newly designed mini-barcodes, MiniB18S_81 showed the higher taxonomic coverage of eukaryotic taxa and a greater amplification and identification capacity for diet and parasite taxa. Moreover, when it was tested on fecal samples from 5 different steppe bird species, MiniB18S_81 showed high taxonomic resolution of the most relevant diet and parasite phyla, Arthropoda, Nematoda, Platyhelminthes, and Apicomplexa at the order level. Thus, the mini-barcode developed emerges as an excellent tool to simultaneously provide detailed information regarding the diet and parasites of birds, essential for conservation and management.  相似文献   
8.
Urban background air pollution is the lowest level of pollution representative for the exposure of general urban population and mainly originates from non-local sources of pollution. Moss bag technique has been predominantly adopted for biomonitoring of trace elements across anthropogenically devastated areas, such as urban and industrial zones. However, the technique has been rarely used for measurement of background air pollution. In this study, element content and concomitant physiological parameters were assessed in the moss Hypnum cupressiforme Hedw. after its exposure within the bags in the Botanical garden (Belgrade, Serbia), as the presumable background area. During the summer of 2014, the moss bags were exposed for 60 days in total, and the sample analyses were performed every 15 days. As a control of the measured physiological parameters, a set of the moss bags was kept within the phytotron, under conditions of optimal-like growth. The total content of 21 elements, photosynthetic pigments (chlorophylls and carotenoids), phenolics, and antioxidative capacity were determined in the moss samples. The levels of trace elements were markedly lower within the Botanical garden in comparison to the street ambient, but still significantly higher than in the moss pristine habitat. However, the performed physiological tests indicated that the vulnerability of the moss during exposure time was not caused by the low trace element enrichment, but probably by the harsh meteorological parameters in an urban area. Finally, the Botanical garden could be assumed as control site for measurement of the urban background pollution, and it might be effectively measured by the moss bag technique.  相似文献   
9.
Effects of Ozone on Tobacco (Nicotiana tabacum L.) Varieties   总被引:4,自引:0,他引:4  
The well-known ozone bioindicator tobacco ( Nicotiana tabacum L.) variety Bel-W3 and six varieties cultivated in Greece were tested for their relative sensitivities to ozone by exposures conducted in controlled-environment chambers (0, 90, 135 and 180 p.p.b. for 20 days at 8 h day−1). Based on the extent of macroscopic symptoms, Bel-W3 was found to be the most sensitive variety, followed by Zichnomirodata (KK6/5), while K63 was the most resistant. There was a differentiation between Bel-W3 and KK6/5, in terms of both magnitude and visual appearance of symptoms. Ozone reduced the plant height, leaf area and dry weights of leaves, stems and roots. The root dry weight reduction was greater than that of leaves and stems. Moreover, gross photosynthesis was reduced by ozone exposure, mainly in the lower leaves. The ozone-related sensitivity could not be attributed to greater stomatal density because (a) the most tolerant and the most resistant varieties had almost the same number of stomata per mm2 and (b) the most resistant leaves (upper) had greater stomatal density than the most sensitive (lower) ones, even in the same plant. Stomatal conductance was greater in the abaxial surface (P < 0.001) than in the adaxial surface and in the upper leaves (P=0.013) than in the lower leaves, but it did not differ significantly between the Bel-W3 and K63 varieties (P=0.3417). The fumigation of grafted plants – Bel-W3 (ozone-sensitive) on K63 (ozone-resistant) and vice versa – suggested that stocks did not affect the ozone sensitivity of scions.  相似文献   
10.
水环境中Cd和Cu污染对监测生物河蚬积累效应的影响   总被引:12,自引:1,他引:12  
以河蚬作为指示生物,采用室内培养方法,研究了不同浓度的 Cd和 Cu的单独及联合作用的毒性效应.结果显示,在水体中浓度为 10、 20、 30、 40、 50 μ g· L-1的 Cd与 Cu单独作用下,河蚬体内 Cd与 Cu的含量分别与其在该环境中的暴露时间和浓度呈显著正相关.在同样浓度的 Cd与 Cu共同存在的环境中,河蚬体内的 Cd与 Cu的含量仍与环境中该物质的浓度呈显著正相关,且随着暴露时间的延长均表现出对污染物质积累的增加.初步建议河蚬可作为淡水中重金属污染的监测指示生物.  相似文献   
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