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991.
992.
为了探究福建省云霄县枇杷叶作为食品原料深加工的前景及产业发展情况,以国内目前关于枇杷叶化学成分及药理活性的研究为基础,综述枇杷叶作为食品原料进行深加工的可行性,分析云霄县得天独厚的枇杷种植情况给枇杷叶深加工提供的有利情况,探究枇杷叶作为食品原料加工食品的品种及范围,拓宽其食品应用市场的前景。 相似文献
993.
994.
吉林省长白森林经营局发展的几点经验 总被引:1,自引:0,他引:1
实施天然林保护工程后,木材产量的大幅度调减给企业带来了巨大的生存压力。在此压力下,吉林省长白森林经营局立足本地实际,充分发挥自然资源优势,选择优势项目进行综合开发,大力发展非林经济。通过关停和出售亏损企业等措施,减轻企业负担,积累企业资金。经过十年的努力,使企业逐步发展成为一个拥有林业、水利电力业和医药业的综合性地方森工企业。 相似文献
995.
Juan Jin Huimei Cui Xinmin Lv Yifan Yang Yi Wang 《The Journal of Horticultural Science and Biotechnology》2017,92(1):98-106
In this study, we investigated the effects of 10 mM CaCl2 on membrane permeability, malondialdehyde (MDA), reactive oxygen species (ROS), and Na+, K+, Ca2+, and Mg2+ concentrations in different organs of sour jujube grown under 150 mM NaCl stress. Our results showed 73% leaf wilting in the Na treatment. The Na treatment significantly increased leaf superoxide (O2.?) production rates, hydrogen peroxide (H2O2) concentrations, cell membrane permeability, MDA concentrations, and Na+ concentrations in roots, stems, and leaves. The Na treatment significantly reduced K+, Ca2+,and Mg2+ concentrations in roots, but increased K+ concentrations in stems. Compared with the Na treatment, 39% of the leaves showed wilting symptoms in the Na+Ca treatment. The Na+Ca treatment significantly decreased leaf O2.? production rates, H2O2 concentrations, cell membrane permeability, and MDA concentrations. Moreover, the Na+Ca treatment (1) significantly reduced Na+ concentrations in roots, stems, and leaves; (2) significantly increased root K+ concentrations; (3) significantly increased K+/Na+ ratios in roots; (4) significantly increased Ca2+ concentrations in stems and leaves, and Mg2+ concentrations in roots. In conclusion, exogenous CaCl2 reduces NaCl stress in sour jujube by reducing Na+ concentrations and increasing K+, Ca2+, and Mg2+ concentrations in various plant organs. 相似文献
996.
北极村樟子松与落叶松林区空气负离子浓度及其与气象因子的关系 总被引:2,自引:0,他引:2
为了揭示空气负氧离子浓度与林种及相关气象条件之间的关系,笔者于2013年夏、秋两季对北极村地区选取的具有代表性的样地进行负氧离子浓度的观测及研究,通过时间尺度平均值及相关性分析的方法,对采集数据进行统计分析,并得出北极村地区负氧离子浓度的总体水平以及其与林种和气象因子之间的变化关系。结果表明:漠河北极村空气负离子浓度的总体水平处于548~1203个/cm~3,平均值为892个/cm~3,负氧离子浓度大体上与空气温度呈正相关、与空气湿度呈负相关。落叶松样地整体负氧离子水平高于樟子松样地,不同季节对负氧离子浓度也有较大影响。揭示出北极村地区负氧离子浓度与林种、季节以及气象因子之间的变化关系。 相似文献
997.
张婷袁伟涛郭肖兰王凯英徐超 《动物营养学报》2023,(4):2571-2579
This experiment was conducted to study the effects of dietary lactic acid bacteria (LAB) and fructooligosaccharides (FOS) on growth performance, nutrient digestibility and serum biochemical indices of Arctic foxes (Alopex lagopus) during early growth period. Sixty male post-litter Arctic foxes with the average body weight of (1.16±0.15) kg and at the age of (45±3) days were randomly assigned to 4 groups with 3 replicates per group and 5 foxes per replicate. The foxes were fed the following diets, respectively: basal diet (control group), basal diet+3×109 CFU / kg LAB (LAB group), basal diet+5 g / kg FOS (FOS group) and basal diet+3×109 CFU / kg LAB+5 g / kg FOS (LAB+FOS group). The experiment lasted for 30 days. The results showed as follows: 1) on the days 1 to 15, the diarrhea rate of foxes in the LAB group and LAB+FOS group was significantly lower than that in the control group and FOS group (P<0.05). On the days 16 to 30, the average daily gain of foxes in the LAB+FOS group was significantly higher than that in the control group and FOS group (P<0.05), but had no significant difference with LAB group (P>0.05); the diarrhea rate of foxes in the LAB+FOS group was significantly lower than that in the control group and FOS group (P<0.05), but had no significant difference with LAB group (P>0.05); compared with the FOS group, the feed to gain ratio of foxes in the LAB+FOS group was significantly decreased (P<0.05). 2) The dry matter digestibility of foxes in the LAB + FOS group was significantly higher than that in the control group and FOS group (P < 0.05), but had no significant difference with LAB group (P>0.05). There were no significant differences in nitrogen intake, fecal nitrogen, urine nitrogen, nitrogen deposition, net protein utilization and protein biological value among all groups (P>0.05). 3) Serum total protein (TP) content of foxes in the LAB+FOS group was significantly higher than that in the FOS group (P<0.05), but had no significant difference with control group and LAB group (P>0.05). Serum albumin (ALB) content of foxes in the LAB group was significantly higher than that in the control group and FOS group (P<0.05), but had no significant difference with LAB+ FOS group (P>0.05). Serum urea nitrogen (UN) content of foxes in the LAB+FOS group was significantly decreased compared with the control group (P < 0. 05). In conclusion, the combined supplementation of 3 × 109 CFU / kg LAB and 5 g / kg FOS in the diet is beneficial to reduce diarrhea rate, improve dry matter digestibility, improve body immune level, and promote the growth of Arctic foxes during early growth period. © 2023 Chinese Journal of Urology. All rights reserved. 相似文献
998.
999.
Stanislas Talaga Frédéric Petitclerc Jean-François Carrias Olivier Dézerald Céline Leroy Régis Céréghino Alain Dejean 《Landscape Ecology》2017,32(9):1805-1818
Context
Many aquatic communities are linked by the aerial dispersal of multiple, interacting species and are thus structured by processes occurring in both the aquatic and terrestrial compartments of the ecosystem.Objectives
To evaluate the environmental factors shaping the aquatic macroinvertebrate communities associated with tank bromeliads in an urban landscape.Methods
Thirty-two bromeliads were georeferenced to assess the spatial distribution of the aquatic meta-habitat in one city. The relative influence of the aquatic and terrestrial habitats on the structure of macroinvertebrate communities was analyzed at four spatial scales (radius = 10, 30, 50, and 70 m) using redundancy analyses.Results
We sorted 18,352 aquatic macroinvertebrates into 29 taxa. Water volume and the amount of organic matter explained a significant part of the taxa variance, regardless of spatial scale. The remaining variance was explained by the meta-habitat size (i.e., the water volume for all of the bromeliads within a given surface area), the distance to the nearest building at small scales, and the surface area of buildings plus ground cover at larger scales. At small scales, the meta-habitat size influenced the two most frequent mosquito species in opposite ways, suggesting spatial competition and coexistence. Greater vegetation cover favored the presence of a top predator.Conclusions
The size of the meta-habitat and urban landscape characteristics influence the structure of aquatic communities in tank bromeliads, including mosquito larval abundance. Modifications to this landscape will affect both the terrestrial and aquatic compartments of the urban ecosystem, offering prospects for mosquito management during urban planning.1000.