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41.
Seed dormancy is an obstacle to revegetation and reclamation efforts, particularly in arid and semiarid environments. Therefore, the objective of this study was to determine the most effective germination pretreatment for Haloxylon persicum, a tall desert shrub or small tree. The experiment employed a completely randomized block design. Dormancy breaking treatments included scarification with 98% sulfuric acid for 10, 20, 30, and 60 minutes; debracting seeds; debracting + piercing seeds; stratification for 1, 2, 3 and 4 weeks; and leaching seeds in flowing water for 1, 2, 3, and 4 days. Results demonstrated that scarification with 98% sulfuric acid for 10 min was the most effective treatment which increased germination from 23.3% (control) to >82.6%.  相似文献   
42.
Journal of Soils and Sediments - This review of sediment source fingerprinting assesses the current state-of-the-art, remaining challenges and emerging themes. It combines inputs from international...  相似文献   
43.
Assessment of soil health requires complex evaluation of properties and functions responsible for a broad range of ecosystem services. Numerous soil quality indices (SQI) have been suggested for the evaluation of specific groups of soil functions, but comparison of various SQI is impossible because they are based on a combination of specific soil properties. To avoid this problem, we suggest an SQI-area approach based on the comparison of the areas on a radar diagram of a combination of chemical, biological and physical properties. The new approach is independent of the SQI principle and allows rapid and simple comparison of parameter groups and soils. Another approach analyzing the resistance and sensitivity of properties to degradation is suggested for a detailed evaluation of soil health. The resistance and sensitivity of soil properties are determined through comparison with the decrease of soil organic carbon (SOC) as a universal parameter responsible for many functions. The SQI-area and resistance/sensitivity approaches were tested based on the recovery of Phaeozems and Chernozems chronosequences after the abandonment of agricultural soils. Both the SQI-area and the resistance/sensitivity approaches are useful for basic and applied research, and for decision-makers to evaluate land-use practices and measure the degree of soil degradation.  相似文献   
44.
It is of crucial importance to study on the biomarkers types to assess the specification of the pollutants and health status of marine ecosystems in environmental evaluation projects. In this respect, total metallothionein biosynthesis and mercury bioaccumulation in the liver and gills under acute mercury exposure were investigated in fish, Scat (Scatophagus argus). Spotted scat was exposed to different mercury concentrations (0, 10, 20, 30) for 24, 48, 72 h. Total MT levels were determined by enzyme-linked immunosorbent assay (ELISA) method. Mercury contents were determined through cold vapor atomic absorption spectrometry (CVAAS). Induction of MT during exposure was tissue specific, displaying different response pattern in gills and liver. Mercury accumulated in liver much higher than in gills and the latter also showed lower MT level (P < 0.05). MT biosynthesis in liver showed a significant (P < 0.05) increase after exposure to different mercury concentration with increase in exposure time, whereas total MT content did not significantly (P > 0.05) change in gills except for 72 h exposure at 30 μg l−1. Nonetheless, the relationship between MT biosynthesis and Mercury bioaccumulation in both tissues was significant (P < 0.05). The results suggest that this form of MT in S. argus was Hg inducible and could be extended as a biomarker of mercury pollution in marine ecosystems.  相似文献   
45.
A study was conducted to investigate the effects of dietary oligofructose (1, 2 and 3%) on the blood profiles of beluga (Huso huso) juveniles (18.77 ± 0.76 g) compared to fish fed an un-supplemented diet. After 7 weeks of feeding on the experimental diets, haematological parameters, metabolic products (cholesterol, glucose and total protein) and serum enzymes (lactate dehydrogenase, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase) were measured. Compared to the control group (0% oligofructose), dietary oligofructose had no effect on red blood cell counts (RBC), mean corpuscular volume (MCV), mean cellular haemoglobin (MCH) or mean cell haemoglobin concentration (MCHC) (P > 0.05). However, haemoglobin (Hb) concentration, leucocyte (WBC) levels and the proportion of lymphocytes were significantly higher (P > 0.05) in the 2% oligofructose fed fish than in the 3% oligofructose fed fish. Additionally, haematocrit (Hct) values (P = 0.049) and the proportion of lymphocytes (P ≤ 0.01) were significantly higher in the 2% oligofructose group than in the control group. Although serum glucose and total protein remained unaffected, serum cholesterol was significantly lower in the 2% oligofructose group than in the control and 3% oligofructose group (P < 0.05). The results of the present study showed that oligofructose had no significant effects on serum lactate dehydrogenase, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase. These results indicate that fish blood profiles could be affected by prebiotics, which should be taken into account in future studies.  相似文献   
46.
The tourism industry has long been recognised for supporting women in achieving economic empowerment and social freedom through entrepreneurial and employment opportunities. Widely recognised as a women-dominated sector, tourism is deemed to be a facilitator of women's development following the UN Sustainable Development Goals (SDGs). As the existing literature suggests, women's involvement in tourism activities supports local economic growth and development, while facilitating social transformation that enables them to create their own identities. Despite these achievements, several studies noted the persisting issues women face in participating in tourism. With the goal of contributing to existing discourses, this paper aims to analyse their experiences in community entrepreneurship by examining several community-involved tourism enterprises in the Philippines. The findings of this study reveal that women have been largely involved in tourism activities in that country, yet their experiences working in these enterprises vary. The opportunities and challenges identified in this study can serve as a springboard for further analysis of the experience of women working in the Philippine tourism industry.  相似文献   
47.
The aim of this study was to investigate the effect of black pepper fruit hot water extract (BPE) on rat ileum contractility and the mechanism(s) of its action. The extract was prepared by adding black pepper powder to boiling distilled water followed by evaporated the solvent. Ileum was dissected from male adult rat (Wistar) and in Tyrode solution the tissue contractions were recorded by an isotonic transducer under 1 g tension. The cumulative concentrations of the BPE (0.0625-1 mg mL(-1)) reduced the ileum contractions induced by KCl (60 mM) or carbachol (10 microM) concentration dependently (p<0.001). In Ca2+-free Tyrode solution with high potassium (60 mM), BPE, (0.0625-1 mg mL(-1)) attenuated the contractions induced by cumulative concentrations of CaCl2 (0.225-2.7 mM) concentration dependently (ANOVA, p<0.05). The incubation of the tissue preparation (20 or 30 min) with L-NAME (100 microM), naloxone (1 microM) or propranolol (1 microM) did not reduce the extract antispasmodic effect on KCl-induced ileum contraction. The extract spasmolytic effect was attenuated neither by glibenclamide (10 microM) nor by tetraethylammonium (1 mM). Present results suggest that the spasmolytic effect of the extract on rat ileum was possibly mediated via Ca2+ influx.  相似文献   
48.
The effect of Mentha longifolia (L.) leaf hydroalcoholic extract (MLE) was examined on rat ileal smooth muscle contractions. Last portion of ileum from male adult Wistar rat was mounted in an organ bath containing Tyrode solution. The tissue was contracted by carbachol (CCh, 10 microM), KCl (60 mM) and BaC12 (4 mM) and then MLE (0.0625-1 mg mL(-1)) was added to the bath cumulatively. The effect of MLE on KCl-induced contraction was examined after tissue incubation with propranolol (1 microM), naloxone (1 microM) and N omega-nitro-L-arginine methyl ester (L-NAME, 100 microM). The effect of MLE on CaCl2-induced ileal contraction in Ca(2+)-free with high potassium Tyrode solution was also evaluated. The role of potassium channels was examined by ileum incubation (5 mim) with tetraethylammonium (TEA, 1 mM). The results showed that KCl-, CCh and BaCl2-induced ileal contractions were inhibited (p < 0.001) by cumulative concentrations of MLE with the same potency. In addition, MLE (0.25-1 mg mL(-1)) inhibited (p < 0.01) ileal contractions induced by CaCl2 (0.45-2.7 mM) in a concentration-related manner. The antispasmodic effect of MLE was affected neither by propranolol, L-NAME nor by naloxone. The MLE concentration-response curve was shifted to the right (p < 0.05) by tissue incubation with TEA. From results it may be suggested that Mentha longifolia hydroalcoholic leaf extract induces its spasmolytic activity mainly through disturbance in calcium mobilization and partly by potassium channels activation. Present results show that Mentha longifolia leaf extract exerts relaxant effects on intestinal smooth muscle, consistent with the traditional use of the plant to treat gastrointestinal disorders such as diarrhea and colic.  相似文献   
49.
In this study, effects of foliar application (with constant 0.2% concentration) of chemical NPK (N20:P10:K20) and organic fertilizers of Biomin (an organic aminochelate fertilizer), Humifolin (a humic acid based fertilizer), Biomin?+?Humifolin, a synthetic macro-micro mixture, soil application of NPK (600?mg.kg?1 of the N20:P10:K20 formulation), and a no fertilizer control were evaluated on growth and quality of chili pepper (Capsicum annuum var annuum) seedlings under greenhouse conditions with cool temperature of 15?±?3?°C. The results showed that most growth and quality traits were best improved by foliar application of Biomin aminochelate followed by Humifolin fertilizer. Higher values for leaf area, leaf number, chlorophyl index, root and shoot biomass, and leaf concentration of soluble sugars, N, K, Ca, and Zn, were attributed to foliar application of Biomin and Humifolin. The mixture of Biomin?+?Humifolin had reduced values of those parameters indicating possible negative interaction when these two organic fertilizers are mixed.  相似文献   
50.
Various organic residues and animal manures represent an excellent matrix material for production of natural-based pellet fertilizers. Fully decomposed cow manure with 50% w/w urea was used for pellet production in densities of 400 or 800 kg/m3, representing low and high compact urea pellets. The growth of coriander (Coriandrum sativum L.), garden cress (Lepidium sativum L.), and parsley (Petroselinum crispum Mill.) were then evaluated under application of these pelleted urea compared to urea alone and unfertilized plants. The total amount of applied nitrogen (N) in the form of urea or pelleted urea was 300 mg/kg soil, wherein pelleted urea treatments, 30% of N was incorporated into the soil as urea alone before planting. The results showed that application of pelleted urea in low and high compactness resulted in different plant responses in the three vegetable crops. Plant growth and biomass production was increased in plants treated with urea or low compact urea pellets. Leaf N concentration and the Soil-Plant Analysis Development (SPAD) index were increased by low but not by high compact urea pellet application. Regardless of compactness, pellet treated plants had less nitrate content compared to urea treated plants. Number of flowering plants in coriander and garden cress was higher with high compact urea pellet and in unfertilized plants, whereas plants treated with urea or with low compact urea pellet showed fewer flowering plants. So, for production of these leafy vegetables low compact pellet is preferred.  相似文献   
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