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81.
基于层次分析法的节水型社会评价研究   总被引:1,自引:0,他引:1  
以郑州市为例,根据实际情况,建立了节水型社会定量评价指标体系,采用层次分析方法对建立的评价指标体系做了评价,计算得出,2010年将初步建立节水型社会,2020年将全面建成与小康社会相适应的节水型社会.  相似文献   
82.
Five diets that contained fresh squid meat as the basic constituent and were supplemented with different amounts of highly unsaturated fatty acids (HUFA) and astaxanthin were fed to pond‐reared Penaeus monodon broodstock. Diet A was sole squid meat. Diets B and C were supplemented with astaxanthin 50 and 100 mg kg?1 respectively. Diets D and E were supplemented with HUFA 5 and 10 g kg?1 and astaxanthin 50 mg kg?1 respectively. The result showed that the group fed diet E had the best reproductive performance in all experimental groups. It had a higher proportion of spawns (71.5%), spawning rate (0.047), a shorter latency period (7.7±0.3 d), higher absolute fecundity (× 103) (361.6±5.5) and egg production/female (× 103) (597.0±18.0) than all the other experimental groups. The fatty acid composition in broodstock diets strongly affected the tissue and fecundity of broodstock. Good correlations between the content of 20:4n‐6 in eggs and the fecundity (r2=0.6109) and egg production (r2=0.9876) of broodstock were found. On the other hand, 22:6n‐3 and DHA/EPA ratio was negatively correlated with the fecundity of broodstock (r2=0.5362, 0.8702 respectively). The result also showed that the balance between n‐3 and n‐6 fatty acid families, total polyunsaturated fatty acids and total saturated fatty acid and 20:5n‐3 (EPA) and 22:6n‐3 (DHA) may play vital roles in maturation and reproductive performance of P. monodon broodstock.  相似文献   
83.
涂显平 《长江蔬菜》2000,(10):45-46
番茄施用酵素菌能促进植株生长发育,提高叶片叶绿素含量和座果率,增产22.60%,其中前期产量增18.5%,并有改善番茄品质,降低发病率的作用。  相似文献   
84.
萝卜新品种热杂60以萝卜雄性不育系1225A为母本,60早90-8-8-3-13自交系为父本配制而成,肉质根近圆形,皮肉白色,生食脆嫩,煮食化渣味甜,具有耐热、早熟、抗病毒病、不易糠心等特点,一般667m^2产2500kg左右,最高可达6000kg以上。  相似文献   
85.
不同栽培方式及不同光照条件对凤尾竹形态影响的研究表明,地栽、光明时间短,凤尾竹植株高大,而盆栽、光照时间长则植株矮小。选择光照适当、通风的地方进行地栽可提高观赏价值。盆栽凤尾竹在不同光照条件下可产生不同视觉效果,具有很强烈的观赏性。  相似文献   
86.
为掌握汉中市小麦条锈病流行规律,提高病害测报的科学性和准确性,采用DPS数据处理系统,对多年来汉中市小麦条锈病测报资料进行了主导因素分析,筛选出影响发病程度的主要因子包括小麦感病品种种植比例(x1)、秋苗病田率(x2)、秋苗单位面积平均病叶数(x3)、1月份平均气温(x6)、上年11月份降雨量(x11)、早春病田率(x18)、3月中旬病田率(x19),与发生程度(y)进行逐步回归分析,建立了发病程度预测模型:y=-6.354 7+0.084 0x1+0.022 8x3+0.662 8x6+0.020 9x11,R2=0.968 7。拟合预测符合率为92.31%,相对误差8.96%。利用预测模型对2014-2016年汉中市小麦条锈病进行预测,预测的病级分别为2.93、3.21、1.92,与2014、2015、2016年发生的实际病级3、3、2相吻合。此模型可应用于生产中小麦条锈病的测报。  相似文献   
87.
Flavan-3-ol monomers and polymers composition of seeds from wild (17) and autochthonous (8) Vitis vinifera grapes growing in northern Tunisia were evaluated. Wild grape seeds were spherical with a small beak and relatively a high seed/berry ratio (~ 18.1%w/w). Local cultivars developed pyriform-shaped seeds with a well-developed beak representing on average 2.2% of total weight of the berry. Flavanol concentrations ranged between 40.9 and 67.5 mg/g FW in seeds from wild accessions and between 48.9 and 96.7 mg/g FW in seeds from cultivated grapes. Differences between accessions were highly significant (p < 0.01) and seeds from cultivar ‘Boukhasla’ showed the highest polyphenols content. Among flavan-3-ol monomers, (+)-catechin was predominant for all ecotypes and generally their abundance was: (+)-catechin (Cat) > (?)-epicatechin (Ec) > (?)-epicatechin-3-O-gallate (EcG). The Cat/Ec ratio was approximately 1.7 for wild grapes while it was about 2.5 for cultivated grapes. Procyanidins in wild seeds differed from cultivated ones by a lower mDP and higher proportions of galloylated derivatives, likely to affect fruit bitterness and astringency. (?)-epicatechin was the main extension subunit in grape seed procyanidins, reaching on average 52% in wild and 58% in cultivated seeds. Hierarchical cluster analysis based on seeds morphometry and procyanidin profile indicated close proximity between some wild and cultivated grapes suggesting that some cultivars derived from ancestral events of local domestication or cross hybridization with native wild plants.  相似文献   
88.

Context

Context Bats are considered as an ecological indicator of habitat quality due to their sensitivity to human-induced ecosystem changes. Hence, we will focus the study on two indicator species of bats as a proxy to evaluate structure and composition of the landscape to analyze anthropic pressures driving changes in patterns.

Objectives

This study develops a spatially-explicit model to highlight key habitat nodes and corridors which are integral for maintaining functional landscape connectivity for bat movement. We focus on a complex mountain landscape and two bat species: greater (Rhinolophus ferrumequinum) and lesser (Rhinolophus hipposideros) horseshoe bats which are known to be sensitive to landscape composition and configuration.

Methods

Species distribution models are used to delineate high-quality foraging habitat for each species using opportunistic ultrasonic bat data. We then performed connectivity analysis combining (modelled) suitable foraging habitat and (known) roost sites. We use graph-theory and the deviation in the probability of connectivity to quantify resilience of the landscape connectivity to perturbations.

Results

Both species were confined to lowlands (<1000 m elevation) and avoided areas with high road densities. Greater horseshoe bats were more generalist than lesser horseshoe bats which tended to be associated with broadleaved and mixed forests.

Conclusions

The spatially-explicit models obtained were proven crucial for prioritizing foraging habitats, roost sites and key corridors for conservation. Hence, our results are being used by key stakeholders to help integrate conservation measures into forest management and conservation planning at the regional level. The approach used can be integrated into conservation initiatives elsewhere.
  相似文献   
89.
‘粉荷’星花玉兰,成蕾早,花蕾产量高。花期2月中旬至3月下旬,花瓣形如荷花,色泽艳丽,花量大,抗性强,病害少,易管理,观赏价值高。  相似文献   
90.
 寻找抑制植物病原菌III型分泌系统的植物源活性小分子化合物,是研发生物安全农药的重要途径之一。本研究采用水煮提取法从十字花科黑腐病菌寄主植物满身红萝卜中提取分离活性小分子化合物,利用高效液相-质谱联用解析出活性物质的单体结构。然后用荧光素酶基因luxAB构建融合报告系统以及定量PCR检测活性物质对十字花科黑腐病菌III型分泌系统的抑制效果,最后采用剪叶接种和压渗接种的方法研究活性小分子物质对十字花科黑腐病菌的生防作用。研究表明,植物鞘氨醇和二氢鞘氨醇对十字花科黑腐病菌III型分泌系统基因的转录表达有一定程度的抑制作用,但是对I、II、IV型分泌系统基因的表达没有明显的抑制作用。植物鞘氨醇在XCM1上影响菌的生长,而二氢鞘氨醇不影响菌的生长。同时,还发现这两种物质能显著降低Xcc在寄主植株满身红萝卜上的病害症状以及能够使Xcc在非寄主植物辣椒上引起过敏反应的能力丧失。该研究结果为深入研究小分子化合物对十字花科黑腐病菌III型分泌系统的作用机制及后续开发植物源抑制剂提供了一定的理论依据。  相似文献   
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