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101.
Temperate volcanic forest surface soils under different forest stands (e.g., Pinus sylvestris L., Cryptomeria japonica, and Quercus serrata) were sampled to study the kinetics of ethylene (C2H4) oxidation and the C2H4 concentrations that effectively inhibit oxidation of atmospheric methane (CH4) and nitrification. The kinetics of C2H4 oxidation in temperate volcanic forest soils was biphasic, indicating that at least two different microbial populations, one with low and another with high apparent K m values, were responsible for ethylene oxidation. Methane consumption activity and ammonium oxidation of soil were inhibited by adding ethylene. Added C2H4 at concentrations of 3, 10, and 20 μl C2H4 per liter in the headspace gas respectively reduced by 20%, 50%, and 100% atmospheric CH4 consumption by soil, and these values were much smaller than those inhibiting ammonium oxidation in these forest soils; thus, the CH4 consumption activity was more sensitive to the addition of C2H4 than ammonium oxidation. Previous studies have shown that accumulation of C2H4 in such volcanic forest soils within 3 days of aerobic and anaerobic incubations can reach a range from 0.2 to 0.3 and from 1.0 to 3.0 μl C2H4 per liter in the headspace gas, respectively. It is suggested that C2H4 production beneath forest floors, particularly after heavy rain, can to some extent affect the capacity of forest surface soils to consume atmospheric CH4, but probably, it has no impact on ammonium oxidation.  相似文献   
102.
Biogas production generates digested slurry as a byproduct. It can be used as a fertilizer especially after its conversion into digested liquid. A pot based study was conducted in order to evaluate the effect of the application of digested liquid on CH4 and N2O flux, and plant biomass in paddy. Analysis revealed that digested liquid treated soils released more CH4 compared to ammonium sulphate and the control. Ammonium sulphate treated soil emitted the highest N2O whereas digested liquid application decreased its emission significantly. Further, the cumulative emission over 101 d of the experiment was found to be higher for CH4 (16.9 to 29.9 g m−2) compared to N2O (−49.3 to 18.9 mg m−2) for all treatments. Digested liquid application had positive impact on plant variables such as panicle number and weight of panicles. This study suggests that digested liquid application significantly decrease N2O emission and increase CH4 emission possibly due to affecting the availability of organic C in the soil to microbial activity for methanogenesis. Another possibility for enhancing CH4 emission by following biogas digested liquid could be attributed to the increase in plant biomass.  相似文献   
103.
104.
Many important apple (Malus × domestica Borkh.) fruit quality traits are regulated by multiple genes, and more information about quantitative trait loci (QTLs) for these traits is required for marker-assisted selection. In this study, we constructed genetic linkage maps of the Japanese apple cultivars ‘Orin’ and ‘Akane’ using F1 seedlings derived from a cross between these cultivars. The ‘Orin’ map consisted of 251 loci covering 17 linkage groups (LGs; total length 1095.3 cM), and the ‘Akane’ map consisted of 291 loci covering 18 LGs (total length 1098.2 cM). We performed QTL analysis for 16 important traits, and found that four QTLs related to harvest time explained about 70% of genetic variation, and these will be useful for marker-assisted selection. The QTL for early harvest time in LG15 was located very close to the QTL for preharvest fruit drop. The QTL for skin color depth was located around the position of MYB1 in LG9, which suggested that alleles harbored by ‘Akane’ are regulating red color depth with different degrees of effect. We also analyzed soluble solids and sugar component contents, and found that a QTL for soluble solids content in LG16 could be explained by the amount of sorbitol and fructose.  相似文献   
105.
Protein-losing enteropathy (PLE) is known to induce hypercoagulability and resultant thromboembolism in dogs. We hypothesized that hypercoagulability would improve if remission was obtained in dogs with PLE after treatment. This study aimed to evaluate the changes in the coagulation parameters after treatment in dogs diagnosed with PLE. As coagulation parameters, prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, thrombin-antithrombin complex (TAT), D-dimer, and antithrombin (AT) were measured. In addition to these parameters, rotational thromboelastometry (ROTEM), which evaluates the comprehensive coagulation and fibrinolysis reactions of whole blood, was conducted and the data of clotting time (CT), clot formation time (CFT), α angle (α), maximum clot firmness (MCF) and lysis index at 60 min (LI60) were obtained. Eleven of the 14 dogs diagnosed with PLE were classified as responders to the treatment based on the changes in their plasma albumin (ALB) concentration after treatment. Significant increase in CFT and decrease of α and MCF indicating the resolution of hypercoagulability were found after treatment in responder dogs; however, there was no significant change in the coagulation and fibrinolysis parameters other than those measured by ROTEM. This study demonstrated that the hypercoagulability detected by ROTEM was significantly improved after treatment in dogs with PLE.  相似文献   
106.
水分管理对水稻生长期N2O排放的影响   总被引:2,自引:0,他引:2  
通过温室盆栽试验研究相同施肥条件下,不同水分管理(持续淹水,分蘖肥后提前烤田、正常烤田和推迟烤田)对水稻生长期N2O排放的影响。结果表明,整个水稻生长期N2O的排放集中在施分蘖肥后的烤田期间及随后复水的5~8天内。在此期间各处理N2O排放量占季节排放总量的70.30%~94.26%;烤田前淹水及后期干湿交替阶段有少量N2O排放。对持续淹水处理而言,N2O的排放通量是正常烤田处理的12.10%。提前烤田、正常烤田和推迟烤田的平均N2O排放通量分别为188.56、158.48和147.84μg/(m2?h),随着烤田开始时间的推迟,N2O排放量逐渐减少。  相似文献   
107.
Paddy and Water Environment - A field experiment was carried out to determine the emissions of nitrous oxide (N2O) and methane (CH4) and yield of rice grains under water management of continuously...  相似文献   
108.
Post-fire forest regeneration is crucial to forest management. Three different restoration treatments including natural regeneration (NR), artificial regeneration (AR), and artificial promotion (AP), were adopted in the Greater Hinggan Mountain area of China after a serious fire occurred on May 6, 1987. NR is a control treatment where recovery occurs naturally without intervention, AR comprises salvage logging followed by planting, while AP includes regeneration by removing dead trees, weeding, and tidying to promote seed germination. In this study, the objective was to detect and compare the effects of the three restoration treatments using radar indices derived from ALOS/PALSAR data. Four time-series SAR images were pre-processed to acquire the backscattering coefficients. Then the coefficients in both HH and HV polarization were examined and two radar vegetation indices were derived and evaluated, based on which, the post-fire forest dynamics under different restoration treatments were detected and compared. The results showed that the forests under NR presented a completely different recovery trajectory compared to those under the other two treatments. This difference could be characterized by both the backscattering intensity in HH and HV polarization and two radar indices. This study indicated the effects of different restoration treatments, as well as demonstrated the applicability and efficiency of radar remote sensing techniques in forest monitoring and management.  相似文献   
109.
110.
We examined the dissolution of polystyrene into p-cymene and related substances to develop an alternative method for the recycling of expanded polystyrene. The dissolving power of p-cymene [212.0 g (100 g solvent)−1] to polystyrene at 50°C compared favorably with those of 2-p-cymenol [156.7 g (100 g solvent)−1], (R)-limonene and its structural isomers [181.7–197.1 g (100 g solvent)−1], and Abies leaf oil [84.7 g (100 g solvent)−1]. The favorable solubility of polystyrene into p-cymene can be explained by the solubility parameter. p-Cymene and polystyrene can be recovered almost quantitatively from the polystyrene solution by simple steam distillation.  相似文献   
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