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71.
我国现俄注册会计师法》存在诸多缺陷,急需从以下方而修改完善:一、确立诚实信用的基本原则。二、确立严格的法律责任。三、明确注册会计师、会计师事务所以及会计师事务所其他从业人员的法律责任关系。四、建立合理规范的注册会计师行业监管体系。五、调整会计师事务所的组织形式。六、做峨注册会计师法》与相关法律的协调。七、明确注册会计师执业准则的法律效力。八、建立注册会计师及会计师事务所的执业责任鉴定制度。九、强制执行注册会计师的执业责任保险。  相似文献   
72.
A cotton cultivar Xinluzao 8 was grown under four levels of water stress treatments (normal irrigation, slight, mild and severe water stress) from the initial reproductive growth stage in Shihezi, Xinjiang, China, in 2002, to evaluate the growth and eco-physiological performances. Under water stress conditions, the transpiration ability decreased while the leaf temperature increased. Although the relative leaf water content decreased as water stress increased, the differences among the treatments were small, indicating that cotton has high ability in maintaining water in leaf. The stomatal density increased as water stress increased, while the maximum stomatal aperture reduced only in the severest stressed plants. The time of the maximum stomatal aperture was delayed in the mild and severe stressed plants. When severe stress occurred, the stomata were kept open until the transpiration decreased to nearly zero, suggesting that the stomata might not be the main factor in adjusting transpiration in cotton. Cotton plant has high adaptation ability to water stress conditions because of decrease in both stomatal conductance and hydraulic conductance from soil-to-leaf pathway. The actual quantum yield of photosystem Ⅱ (PS Ⅱ) decreased under water stress conditions, while the maximum quantum yield of PS Ⅱ did not vary among treatments, suggesting that PS II would not be damaged by water stress. The total dry weight reduced as water stress increased.  相似文献   
73.
土壤含水量对枣幼树生长及水分生理指标的影响   总被引:4,自引:0,他引:4  
本试验研究了不同土壤相对含水量(30%-100%)对金丝小枣盆栽幼树生长、叶片组织含水量、蒸腾强度、气孔扩散阻力的影响。初步确定适宜金丝小枣生长的土壤相对含水量为70%。结果还表明,土壤水分严重亏缺时,叶片组织含水量减少,叶片气孔扩散阻力明显增大,蒸腾强度显著降低。气孔扩散阻力与蒸腾强度呈负相关。但当土壤相对含水量在较高范围内(50-100%)变化时,对叶片组织含水量、蒸腾强度和气孔扩散阻力影响不大。  相似文献   
74.
为研究保卫细胞液泡(GCV)的pH在气孔保卫细胞渗透调节中的作用及蚕豆(Vicia faba)叶片气孔GCV中的颗粒物的性质,本实验采用激光共聚焦显微术配合pH荧光探针BCECF AM的荧光比值法对ABA诱导的气孔关闭过程进行观测,发现:蚕豆气孔关闭过程中GCV的pH升高约0.5(pH5.3→5.8)。分别用pH5.3和5.8的Mes/Tris缓冲液调控离体开放态GCV的pH,透射电镜(4×104倍)观察负染片说明:pH 5.3对开放态GCV液所含颗粒物的线度及分布密度无实质影响;而pH 5.8的处理使取自开放态GCV液所含颗粒物的线度明显增大、分布密度显著减小;非特异性蛋白酶Proteinase K处理可使GCV中的颗粒物消失。基于GCV内颗粒物的线度、形状及对pH调控和对Proteinase K处理的响应,推测此种颗粒物是蛋白质。  相似文献   
75.
大兴安岭林区重特大森林火灾扑救时限预测模型构建研究   总被引:1,自引:0,他引:1  
针对内蒙古大兴安岭林区重特大森林火灾发生频、损失大、危害重、扑救难等特点,在分析影响其发生、蔓延与扑救的主要因子基础上,运用多元线性回归方法,构建重特大森林火灾扑救多元线性回归、预测灭火时限的经验统计模型,经回归拟合和预测检验,其平均相对误差小于8.60%.该模型可为内蒙古大兴安岭林区重特大森林火灾扑救时限预测与决策提供科学的参考依据.  相似文献   
76.
A two-year field experiment was performed in order to evaluate the suitability of de-oiled olive pomace for soil management in a young super high-density olive orchard. In the literature there are not works on this topic.  相似文献   
77.
Mulch is considered a desirable management technology for conserving soil moisture, improving soil temperature and soil quality. This study aimed to investigate soil conditions and hot pepper (Capsicum annuum L.) performance in terms of leaf photosynthetic capacity, fruit yield and quality, and irrigation water use efficiency (IWUE) under such practices in greenhouse condition. A field experiment across 3 years was carried out with four types of mulch (without mulch [CK], wheat straw mulch [SM], plastic film mulch [FM], and combined mulch with plastic film and wheat straw [CM]). Mulch could improve soil physical properties regardless of mulch materials. FM and CM treatments improved soil moistures status and soil temperature in comparison to CK control, while SM increased soil water content and decreased soil temperature. Mulch increased leaf net photosynthesis rate (PN), stomatal conductance to water vapor (gs), intercellular CO2 concentration (Ci), and transpiration rate (E), but declined instant water use efficiency (WUEi). No significant effect of mulch application on chlorophyll fluorescence was existent for the entire growth season. Fruit yield and irrigation water use efficiency (IWUE) showed some increment under all the mulch conditions. Compared to CK, the yield was enhanced by 82.3%, 65.0%, and 111.5% in 2008; 38.1%, 17.4%, and 46.5% in 2009; and 14.3%, 6.5%, and 19.6% in 2010 under SM, FM, and CM conditions, respectively. Although FM produced better fruit quality than other treatments, CM is the recommended practice for hot pepper cultivation in greenhouse condition due to working well to facilitate soil condition (moisture and temperature), plant growth, and marketable yield.  相似文献   
78.
选取10个品种的芍药作为研究对象,观察芍药叶片气孔的形态、分布规律,并对其气孔大小、气孔长宽比、表皮细胞密度、气孔密度及气孔指数等进行品种间比较及差异分析.结果表明:10个品种的芍药叶片气孔形态及分布规律一致.各项指标的品种内变异系数均较小.4个品种(1、2、8、9)的4项指标(气孔长度、宽度、长宽比及气孔指数)均没有差异.2个品种(1、9)的5项指标(气孔长度、宽度、长宽比、气孔密度及气孔指数)均没有差异.各项指标相比较,气孔宽度和气孔指数在各品种间变化较小.气孔密度与气孔长度呈反相关.结果不支持将气孔长度、宽度、气孔长宽比、气孔密度、气孔指数及表皮细胞密度作为芍药种或品种分类的依据.  相似文献   
79.
土壤水分及环境因子对刺楸叶片气体交换的影响   总被引:9,自引:1,他引:9  
通过测定不同土壤水分条件下,3a生盆栽刺楸苗木的气体交换参数及其周围环境因子,探讨土壤水分及微气候因子对光合速率、蒸腾速率、气孔导度等气体交换参数的影响规律。结果表明:随着水分胁迫的加剧,刺楸叶片蒸腾速率、净光合速率和气孔导度总体上表现出减小的趋势,且随着胁迫的加剧,下降的幅度越大,蒸腾速率、净光合速率和气孔导度在重度、中度、轻度胁迫下日均值分别比对照下降6 6 % ,2 5 %和16 % ,81% ,30 %及5 1% ,70 % ,17%和14 %。随着土壤水分的减少,净光合速率下降逐渐由气孔限制转变为非气孔限制,水分利用效率并未完全表现出下降的趋势,日平均值表现为对照>中度>轻度>重度。逐步回归分析表明,刺楸苗木叶片水气交换参数,不仅受土壤水分的影响,同时也受外界环境因子的综合影响,且影响程度差异较大,回归方程相关系数较好  相似文献   
80.
Species can become regionally rare when limited by the availability of suitable habitats or by limited dispersal ability. We tested if the presence of a rare bryophyte species (Sphagnum angermanicum) was dispersal or habitat limited and at the same time investigated the possibility of establishing new populations of this rare species. Further, we tested how propagule (fragment) size and small scale disturbances affected establishment success. All field experiments were performed by artificially transporting propagules (of various sizes) to new and old sites for the species in Sweden.We show that S. angermanicum is dispersal limited on a regional scale, as no significant differences in establishment success were found between new suitable sites and old occupied sites. The larger the propagule the better was the establishment success; the best establishment success was found when transplanting whole shoots. Disturbances did not increase establishment success, in contrary, when compared to controls success was reduced by the more intensive disturbance treatments. We suggest that disturbance maybe more important for increasing direct dispersal than for making the microhabitat more advantageous for establishment. However, an intermediate disturbance, which slightly reduces the Sphagnum-community length increment, might also be beneficial for the establishment success of S. angermanicum propagules.The reasonably high establishment success of S. angermanicum propagules in new suitable sites suggests that artificial introductions of fragments could be considered as an active management regime for the species if the number of localities continues to decrease.  相似文献   
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