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101.
The structure of forest stands changes through developmental phases. This study is carried out in the unmanaged, oriental beech (Fagus orientalis Lipsky) stands in the north of Iran. The aim of this research was to quantify structural characteristics of stands in the stem exclusion phase using common structural indices, which include mingling, tree–tree distance, stem diameter, and tree height differentiation. According to our measurements from three stands, naturally regenerated stands tend to be mixed in species composition have slightly heterogeneous diameter distributions and uniform tree height. The average distance between trees was 3.3 m. Stocking volume of the stands had an average of 540 m3 ha?1 and 412 stem ha?1. Dead wood volume was 24 m3 ha?1, and as a standing volume, the most frequent species in dead wood pool was oriental beech (F. orientalis) (48 %). The common form of dead trees was snag (41 %). The mean value of mingling and tree-to-tree interval indices revealed that beech was mixed intensively with hornbeam and appears to be a more successful competitor for space and light compared with hornbeam; moreover, we found relatively high evidence of inter-species competition in this phase. A better understanding of stand characteristics in the stem exclusion phase as a critical part of the natural dynamics of forest ecosystems could facilitate predictions about the future changes within the stand. 相似文献
102.
The use of fenugreek seed meal in fish diets: growth performance,haematological and biochemical parameters,survival and stress resistance of common carp (Cyprinus carpio L.) 
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下载免费PDF全文 Zahra Roohi Mohammad Reza Imanpoor Valiolah Jafari Vahid Taghizadeh 《Aquaculture Research》2017,48(3):1209-1215
The present study was conducted to investigate the effects of fenugreek seed meal (FKSM) on growth performance, blood haematological and biochemical factors, survival and stress resistance of the common carp (2.46 ± 0.06 g) fingerlings. Four practical diets containing 0 (control), 0.5%, 1% and 1.5% FKSM were used to feed fish. Fish were fed on the tested diets at a rate of 3% of body weight for 8 weeks. Results indicated that fish fed the control diet had a significantly lower weight gain, specific growth rate and condition factor compared to the other treatments (P < 0.05). Feed conversion ratio decreased significantly in fish fed diets containing FKSM. There were no significant differences in glucose levels, red blood cell count, haematocrit and haemoglobin between treatment groups and the control group (P > 0.05). Significantly lower white blood cells count was observed in fish treatment with FKSM when compared with the control group (P < 0.05). The cholesterol level in group fed supplemented diet by 1% fenugreek significantly lower than other groups (P < 0.05). Total protein levels were significantly higher in all treatments compared to the control (P < 0.05). No mortality was recorded during the feeding trial. In salinity stress experiment, highest survival rate belong to fish fed supplemented diet by 1% fenugreek. These results indicate that FKSM can be considered as a beneficial dietary supplement for improving the growth performance and blood indices of common carp fingerling. 相似文献
103.
Mohammad Zakeri Jasem G. Marammazi Preeta Kochanian Ahmad Savari Vahid Yavari Mahsa Haghi 《Aquaculture (Amsterdam, Netherlands)》2009,295(1-2):99-105
A study was conducted to determine the effects of dietary protein and lipid concentrations on growth, spawning performance and egg quality of yellowfin sea bream, Acanthopagrus latus. Nine diets representing a combination of three protein concentrations (40, 50 and 60%) and three lipid concentrations (15, 20 and 25%) were tested with three replicates. Each replicate was stocked with 10 fish with a sex ratio of 1:1 and the average weights were 415 g and 236 g for females and males, respectively. Fish were fed to satiation twice daily. The weight gain of A. latus broodstock was not significantly (P > 0.05) different among fish fed diets with the various protein and lipid concentrations. Except for relative fecundity and survival rate of 3-day-post-hatch (3DPH) larvae, spawning performance of A. latus was not significantly affected by different concentrations of dietary protein or lipid. Relative fecundity was found to be significantly elevated by dietary lipid at 20% concentration. However, survival rate of 3DPH larvae was highest from broodstock fed diets with 40% protein and 25% lipid, 50% protein and 15% lipid and 60% protein and 15% lipid concentrations. Egg diameter generally increased with increasing dietary protein from 40 to 60% at each lipid concentration. Total length of hatchlings followed an inverse relationship with dietary protein regardless of the lipid concentration. The oil globule diameter (OGD) of hatchlings significantly increased with decreasing dietary protein from 60 to 40%. Yolk sac length (YSL) and OGD of hatchlings was generally greatest at 15% dietary lipid concentration irrespective of protein concentrations. Total length of 3DPH larvae was greatest from broodstock fed diets with 50% protein and 20% lipid, respectively. Body protein content of broodstock was not significantly affected by dietary protein and lipid concentrations. However, increasing dietary lipid generally resulted in increasing body lipid content regardless of the dietary protein concentration. Protein and lipid contents of eggs, hatchlings and 3DPH larvae were significantly affected by dietary protein and lipid concentrations of the broodstock diets. The present study revealed that the best reproductive performance of A. latus broodstock was achieved at 40% dietary protein and 20% dietary lipid concentrations based on relative fecundity, fertilization rate, hatchability and survival of 3DPH larvae. 相似文献
104.
Three geomorphological models, based on linear reservoirs cascade, are developed; two of the models are unit hydrograph (UH) models and one contains a non-linear routing approach. In the first UH model, each sub-basin is represented as a cascade of equal linear reservoirs (Nash's model) which directly discharges to the watershed outlet through a linear channel. In the second UH model each sub-basin is represented as a linear reservoir arranged in a sequence based on the drainage network. For both unit hydrograph models, parameters are explicitly derived, which make the models simple and applicable for real world problems. In the third model, output hydrographs of the sub-basins are calculated by the Nash model but with consideration of geomorphological properties of the sub-basins. Then, the obtained hydrographs are routed through the main channel using a non-linear kinematic wave model. Combination of the kinematic wave routing model (a non-linear routing model) and the Nash model (a linear lumped model) makes this third model more appropriate for runoff modeling.Two important properties of these three models are that they consider the effect of watershed geomorphology and include only one parameter which can be estimated using observed rainfall–runoff data. GIS tools are used for determining the watershed geomorphological parameters. The results of these models are compared with the Nash's black box and the geomorphological SCS models for the Amameh watershed, Iran. Although the results show that the proposed models yield good efficiency in rainfall–runoff modeling, the semi-distributed routing ability in the second and third models produces better results. 相似文献
105.
Akbar Abbaszadeh Saeed Keyvanshokooh Vahid Yavari Mahdi Naderi 《Aquaculture Nutrition》2019,25(2):358-366
The objective of the study was to examine the effects of biofloc technology on the muscle proteome of Litopenaeus vannamei. Two biofloc treatments and one control were compared: biofloc‐based tanks under zero‐water exchange fed with 150 g/kg crude protein (BF15), or with 250 g/kg crude protein (BF25) diets, and clear water tanks with 50% of daily water exchange stocked with shrimp fed with similar amount of a 250 g/kg crude protein diet, referred to as control. The shrimp (5.28 ± 0.42 g) were divided into the 300‐L fibreglass tanks (water volume of 200 L) at a density of 35 shrimp per tank and were cultured for 35 days. The biofloc groups displayed better growth and survival compared to the control. The muscle tissue from the control and BF25 groups was subjected to proteomic analysis. Lactate dehydrogenase, enolase, arginine kinase, mitochondrial ATP synthase subunit alpha, mitochondrial ATPase inhibitor factor 1 precursor, serpin 3 and myeloid differentiation factor 88 had an increased abundance in the BF25 group, while myosin heavy chain type 1 and myosin heavy chain type 2 showed a decreased abundance. The results indicate that biofloc technology could alter the expression of proteins involved in structure, metabolism and immune status of cultured shrimp. 相似文献
106.
Hamed Aalamifar Siyavash Soltanian Arya Vazirzadeh Mostafa Akhlaghi Vahid Morshedi Amin Gholamhosseini Mansour Torfi Mozanzadeh 《Aquaculture Nutrition》2020,26(1):156-164
A six‐week feeding trial was conducted to determine the effect of butyric acid (BA) inclusion in diet on performance of Barramundi (Lates calcarifer). Fish (12.0 ± 0.2 g) were fed with four experimental diets contained 0.0 (control), 2.5, 5.0 and 10.0 g BA/kg in triplicate. Fish fed on 5 and 10 g BA/kg diets had higher growth and total alkaline protease and lipase activities than the other treatments. Fillet protein content in BA‐supplemented groups was higher than the control. Liver catalase activity was highest in 2.5 g BA/kg group compared with the other groups. The values of liver superoxide dismutase activity and serum total protein concentration in 5 and 10 g BA/kg treatments were higher than those in the control (p < .05). Moreover, the highest and the lowest levels of serum lysozyme activity were noticed in the 10 g BA/kg and the control groups, respectively (p < .05). Also, the highest respiratory burst activity was observed in fish fed 5 g BA/kg feed. Supplementing diet with 2.5 or 5 g BA/kg resulted in higher serum haemolytic activity in fish compared with the other groups. The number of red and white blood cells increased in fish fed BA‐supplemented diets compared with the control (p < .05). In conclusion, the results of this study showed inclusion of BA at 5 g/kg diet in L. calcarifer juveniles improved growth and upgraded the general health condition by enhancing fish antioxidant enzyme activities and haemato‐immunological responses. 相似文献
107.
Vahid Hemmati Majid Jamshidian Mohammad Safari Ali Moayedi 《Journal Of Aquatic Food Product Technology》2018,27(3):327-337
The functional and in vitro antioxidant properties of common kilka fish protein hydrolysates with different degree of hydrolysis (DH) obtained by kiwifruit protease (KP) and ginger protease (GP) were evaluated. The electrophoretic patterns of hydrolysates showed the presence of one major band in different DHs with a molecular weight of less than 25 kDa. Protein solubility was positively correlated with DH, and the solubility of KP and GP hydrolysates (HKP and HGP, respectively) at 15% DH was higher than other DHs (p ≤ 0.05). Higher emulsifying and foaming properties were observed in HKP over a pH range of 2–10 (p ≤ 0.05), and in vitro antioxidant activity was higher in HKP at 15% DH as seen from 2,2-diphenyl-1-picrylhydrazyl radical scavenging and ferric-reducing power. Thus, the results reveal that DH and enzyme type affects functional properties and antioxidant activity of the hydrolysates. 相似文献
108.
Farhad Azarmi Vahid Mozaffari Mohsen Hamidpour Payman Abbaszadeh-Dahaji 《Communications in Soil Science and Plant Analysis》2016,47(8):955-972
The role of fluorescent pseudomonads isolates (pf0, pf1, pf2, and pf3) and zinc (Zn) (0 and 5 mg kg?1 soil) interactions in alleviating salinity in pistachio seedlings were investigated. The experiment was conducted following completely randomized design with three replicates. The results revealed that salinity decreased the growth parameters, while application of PGPR (plant growth-promoting rhizobacteria) and Zn increased these parameters. Application of PGPR significantly enhanced phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), Zn, Ca/sodium (Na), and K/Na contents, while decreased the accumulation of Na and chloride (Cl). Application of PGPR and Zn increased the phenolic compounds, sucrose, membrane stability index (MSI), and relative water content (RWC) but reduced the malondialdehyde (MDA) amount. A positive correlation was observed between Zn concentrations with seedling dry weights, phenolic compounds, MSI, and RWC contents. These results indicated that the combined application of PGPR and Zn could be a simple treatment for growth and establishment of pistachio seedlings under Zn deficiency and soil salinity. 相似文献
109.
Mahdi Banaee Fahimeh Fallahpour Vahid Soleimany Behzad Nematdoost Haghi 《Journal Of Applied Aquaculture》2013,25(2):92-109
ABSTRACTThis study was conducted to evaluate the effects of marshmallow extract (Althaea officinalis L.) administration on blood cells and biochemical parameters of carp liver. A total of 150 carps (Cyprinus carpio, initial body mass of 37.7 ± 4.4 g) were fed diets containing 0.0 (control diet), 2.5, 5, and 10 g marshmallow extract for 60 days. On days 30 and 60 of the experiment blood samples were collected and hematological parameters and liver enzyme activities—aspartate aminotransferase (AST), alanine amino transferase (ALT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP)—were measured. No significant difference was found (p > .05) in red blood cells (RBC); hemoglobin concentration (Hb); hematocrit (Htc); mean corpuscular volume (MCV); mean corpuscular hemoglobin concentration (MCH); or the percentage of neutrophils, basophils, and eosinophils in fish fed with different concentrations of marshmallow extract on days 30 and 60. However, the white blood cell (WBC) count was increased significantly in the fish fed for 60 days with feed supplemented with 5 g marshmallow extract (p < .05). The MCHC was increased signi?cantly in ?sh fed with diets supplemented with 2.5 g marshmallow extract for 60 days (p < .05). Administration of marshmallow extract (5 g) significantly increased (p < 0.05) lymphocytes on days 30 and 60. However, dietary intake of 10 g marshmallow extract had significantly decreased the monocyte percentage after 60 days. A significant increase was observed in AST, ALT, ALP, and LDH levels in livers of fish fed with extract 10 g, which may be attributed to cytotoxicity. However, marshmallow extract 2.5 and 5 g did not have adverse effects on liver enzymes. These results indicate that preclinical dietary supplementations of 2.5 and 5 g marshmallow extract per kg diet have no side effects on common carp. 相似文献
110.
Haideh Vahid Afagh Hossein Riahi Ramazan Ali Khavari-Nejad 《Communications in Soil Science and Plant Analysis》2019,50(5):538-548
To investigate the effect of Spent Mushroom Compost (SMC) as an organic fertilizer on German chamomile (Matricaria recutita L.) nutrient, growth, yield, essential oil and osmolytes a greenhouse experiment was conducted through a randomized complete design in six replications. A mixture of sandy loam soil with 5, 10 and 15% volume rates of spent mushroom compost was used as the partial substrate for German chamomile pot culture. Finding of results revealed that usage of SMC in the growing media increased significantly plant growth, flower yield, essential macro nutrient uptake, sodium concentration, proline and soluble sugars content as well as essential oil percentages in compared to control. Comparison between the treatments indicated that addition of 10% SMC to the plant soil substrate cause to higher growth and addition of higher rates of SMC (10% and 15%) led to better yield. The obtained results showed that absorption of K and Na enhanced significantly by increasing of SMC percentage in growing media but there was no significant difference in N and P uptake in SMC treatments. The results of GC and GC-MS analysis presented that the main compositions of essential oil extracted from German chamomile flowers accounted for 83.99–99.84% of total essential oil in SMC treatments. Regarding important role of SMC on the essential oil yield, we can consider SMC could be a suitable substitute for chemical fertilizers as environmentally friendly material in cultivation medicinal plant German chamomile. 相似文献