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1.
根据塔里木河流域近50 a来的水文、经济资料,运用数理统计方法分析了自然驱动因子和人文驱动因子对塔里木河流域水域环境影响的贡献率。结果显示:塔里木河四源流在过去50 a出山口径流量没有减少,但汇入塔里木河干流的水量从20世纪50年代的50.27亿m3减少到2000年以后的46.05亿m3,并且出现干流断流长度增加、地下水位下降、水质矿化度升高等一系列问题。而导致这种恶化的直接原因是人类活动的干扰,如:耕地面积扩大,不合理的灌溉、垦殖、放牧等。因此,今后塔里木河流域在水资源利用和综合治理中,应特别关注人类活动的影响。 相似文献
2.
结合塔里木河流域近50多年来的水文、气象及遥感等资料,采用数理统计方法分析了塔里木河径流量变化对下游地区沙漠化的影响。结果表明,自20世纪50年代以来,由于人类活动的干扰和塔里木河不同河段水资源分布的不均匀,使塔里木河下游的径流量在不断的减少,导致下游河段断流,湖泊干涸,并对下游地区的地下水位、植被、沙尘暴及大风天气、沙漠化程度都产生了负面影响。而且河流径流量、地下水位、植被、沙漠化之间是相互影响,相互制约的,存在着内在的联系,在整个生态系统中牵一发而动全身,尤其是在生态环境脆弱的干旱、半干旱区。因此,在对水、土等资源的利用过程中,要注重整体效益。 相似文献
3.
E. Ozturk N. Ocak I. Coskun S. Turhan G. Erener 《Journal of animal physiology and animal nutrition》2010,94(1):78-85
The present study aimed at evaluating the effects of different doses of humic substances (HS) in waterer pan on broiler performances and meat quality. For the trial, 480 chicks (ROSS 308) were allocated into four groups (HS0, HS150, HS300 and HS450) of 120 equally mixed‐sex birds, each receiving a drinking water supplemented with 0, 150, 300 and 450 ppm of a humic acid (provided by 0.0%, 0.5%, 1.0% and 1.5% of HS, v/v) respectively. At the age of 21 and 42 days, feed consumption and live weight were taken. At the age of 42 days, 16 birds per treatment were slaughtered, dressing percentages, digestive tract traits were evaluated and samples of breast (pectoralis major) and thigh (iliotibialis) meat were taken to evaluate the changes in colour characteristics (CIE L*, a* and b*) and chemical composition. The body weight gain increased by the HS300 in relation to the HS0 and HS450, and decreased by the HS450 in relation to the HS0. The feed consumption of birds in the HS450 and feed efficiency of birds in the HS300 were lower and higher than those in the other treatments respectively. The carcass weight of broilers in the HS150 and HS300 were higher than those of in the HS0 and HS450. The carcass weight decreased by the HS450 in relation to the other treatments. The dressing percentage increased by the HS150 in relation to the HS450. The HS450 resulted in breast and thigh meat colour that were lighter than those found in the HS0 birds. The HS450 increased fat content of thigh meat in relation to the HS0. It was concluded that the humic acid supplementation at 300 ppm and 450 ppm appears to have a measurable impact on live performance improving feed efficiency and lightness of breast and thigh meat colours in broilers respectively. 相似文献
4.
塔里木河下游生态输水对植被恢复和沙漠化逆转的影响 总被引：2，自引：1，他引：1
针对近50 a来人类不合理的资源开发,导致塔里木河下游地区沙漠化程度加剧等一系列生态环境问题,结合实地考察和野外调查资料以及遥感影像数据,运用植被覆盖度、沙漠化动态度模型分析法,对塔里木河下游生态输水前后植被和沙漠化状况进行了分析。研究结果表明,生态输水后,植被覆盖度增大,植物种数明显增加;胡杨冠幅增大;裸地、沙地面积减少;非沙漠化和轻度沙漠化土地面积不断扩大,而重度沙漠化面积有减小趋势。生态输水对塔里木河下游植被恢复和沙漠化逆转起到了明显的作用。 相似文献
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The goals of the present study were to determine ifCylindrocarpon olidum var.olidum exerts antibiotic activity on teliospore germination ofTilletia laevis in vitro and to evaluate the efficacy of a seed treatment with this antagonist against artificial seedborne infection in the field
under natural cropping conditions. Germination of bunt teliospores was completely inhibitedin vitro on water agar medium supplemented with the antagonist’s culture filtrate. In field experiments seed application reduced the
incidence of common bunt from 82.9% to 40.4%, and from 81.4% to 42.0% in 1995/1996 and 1997/1998, respectively.C. olidum var.olidum may have a potential againstT. laevis and is worthy of further research on its use as a biocontrol agent for common bunt.
http://www.phytoparasitica.org posting July 14, 2005. 相似文献
7.
Nedim Tetik Irfan Turhan Hatice Reyhan Oziyci Hamide Gubbuk Mustafa Karhan Sezai Ercisli 《Scientia Horticulturae》2011
Carob (Ceratonia siliqua L.) is natively grown in the coastal areas of the Aegean and Mediterranean region in Turkey. The main carob growing areas (Mediterranean and Aegean) were surveyed and a total 70 promising wild and grafted carob genotypes were selected based on physical and chemical pod properties. Preliminary results showed that Turkey has very rich carob genetic resources containing considerable variations for most of the pod traits. In general, wild carob had smaller pods than the grafted ones. Pod mass ranged from 29.16 g to 120.28 g in the wild genotypes and 71.71 g to 147.91 g in the grafted genotypes with an average 107.61 g for the grafted and 63.72 g for the wild genotypes. The average pod dimensions (width, length and thickness) were 18.16 mm, 16.18 cm and 6.42 mm for the wild genotypes and 21.79 mm, 16.91 cm and 8.79 mm for the grafted genotypes. The average soluble solid content ranged from 59.42% in the wild and 64.06% in the grafted genotypes. The average total acidity of the wild and grafted genotypes was similar (0.78%). The pod traits of the wild genotypes differ significantly from those of the grafted genotypes, and the wild genotypes showed higher variations in these traits compared to the grafted genotypes. 相似文献
8.
Electropolymerization of carbazole (Cz) by cyclic voltammetry (CV) onto carbon fiber microelectrodes (CFME) (diameter ∼7 μm)
in dichloromethane (CH2Cl2) solution of 0.1 mol·dm−3 tetraethyl ammonium perchlorate (TEAP) results in the formation of polycarbazole (PCz) thin film coatings. CV results showed
that these PCz thin films have reversible redox behavior in monomer-free electrolyte solution. The resulting thin polymer
films were characterized using Fourier transform infrared attenuated total reflectance spectroscopy (FTIR-ATR) and atomic
force microscopy (AFM). Results performed at optimum experimental conditions indicate that electrodes show a reversible and
stable behavior over sixty eight days of testing for dopamine in 100 μmol·dm−3 buffer solution. A detection limit for PCz thin films as low as 0.1 μM (3S/N) was obtained for the polycarbazole (PCz) thin
films formed using CV. Hence, this novel sensor can be considered as promising sensor for dopamine detection. 相似文献
9.
E. Turhan L. Karni H. Aktas G. Deventurero D. C. Chang A. Bar-Tal 《The Journal of Horticultural Science and Biotechnology》2013,88(4):661-667
SummaryThe aim of the present research was to study changes in the major anti-oxidative enzyme activities known to be associated with the apoplast, during the induction of blossom-end rot (BER) in bell pepper (Capsicum annuum L.) fruits grown under saline conditions. Pepper plants of the BER-sensitive cv. ‘Mazurka’ and less-sensitive cv. ‘Selica’ were grown under control, low- and high-salinity irrigation regimes. Fruits were harvested continuously and, after approx. 7 months under these conditions, BER symptoms started to appear (in the Spring season) and fruits were sampled for biochemical measurements. The intercellular washing fluid (IWF; apoplast fraction) of the fruit pericarp was prepared and enzyme activities in that fraction were determined. The results showed that production of reactive oxygen species (ROS) in the fruit apoplast was higher in ‘Mazurka’ than in ‘Selica’. Apoplastic peroxidase and superoxide dismutase (SOD) activities, and the concentration of ascorbic acid, increased during ‘Selica’ fruit development, whereas the concentration of H2O2 decreased. During the stage of rapid growth, when fruits are most susceptible to BER, apoplastic peroxidase activity was greatly enhanced in the healthy pericarp of BER-affected fruits compared to healthy fruits. Under saline conditions, apoplastic peroxidase and SOD activities, as well as ascorbic acid and H2O2 levels, increased in healthy fruits of the resistant cultivar ‘Selica’; whereas, in healthy fruit of the BER-sensitive cultivar ‘Mazurka’, apoplastic peroxidase activity decreased while the level of ascorbic acid increased, but to a much lesser extent than in ‘Selica’. SOD activity and H2O2 levels increased similarly in both cultivars with increasing levels of salinity. It is proposed that apoplast-associated peroxidase activity and ascorbic acid concentration are increased coordinately in response to salt stress and may be part of a protective anti-oxidation mechanism that determines cultivar sensitivity to BER. 相似文献
10.
Hayrettin Kuşçu Ahmet Turhan Neşe Özmen Pınar Aydınol Ali O. Demir 《Archives of Agronomy and Soil Science》2016,62(10):1396-1410
The main objective of this investigation was to evaluate the response of red pepper grown in a subhumid climate to different irrigation and nitrogen levels. Open-field trials were conducted in the Marmara Region, Turkey. Plants were subjected to three water levels [full irrigation (FI) = 100% crop evapotranspiration (ETc) and two deficit irrigations (DIs)= 66 and 33% ETc restoration] and four levels of N (0, 80, 160, and 240 kg N ha?1) during the 2012, 2013, and 2014 growing seasons. A split-plot experimental design was used. The highest values of biomass and marketable yield (MY) were observed under FI. DI significantly increased the fruit soluble solids content. The biomass yield, MY, and fruit weight significantly improved with increasing nitrogen levels. The 240 kg N ha?1 treatment under FI provided the maximum net income. Increasing N supply under DI conditions enhanced the water-use efficiency based on both biomass yield and MY. These results indicate that with respect to the yield, the net income, and the water productivity of red pepper, the FI with a nitrogen supply of 160–240 kg ha?1 is recommended for drip irrigated and N-fertigated red pepper under subhumid climate conditions. 相似文献