冰温状态下蓝莓质量损失率与质构参数变化规律及相关分析

【目的】研究冰温状态下蓝莓鲜果质量损失率与质构参数随时间的变化规律及其相关性,为蓝莓鲜果采后品质预测及感官评价提供理论依据。【方法】以‘北村’蓝莓为试验材料,(-1±0.5)℃为冰温组,(4±0.5)℃为对照组,分别对2种温度状态下蓝莓鲜果质量损失率及硬度、脆性、弹性、咀嚼性、内聚性和黏附性等6项质构参数进行测定,通过数据拟合与线性回归反映出蓝莓鲜果质量损失率与质构参数随时间的变化规律,进行相关性分析确定与蓝莓鲜果质量损失率呈显著相关的质构参数。【结果】冰温状态下,蓝莓鲜果质量损失率Y与时间X₀的拟合模型为Y=0.197 36exp(X₀/5.850 47)-0.184 5,呈指数式增长,增长趋势明显小于对照组;蓝莓鲜果各项质构参数在试验期间随时间呈不同程度的下降趋势,且均优于对照组。蓝莓鲜果冰温下质量损失率Y与硬度X₁、脆性X₂、咀嚼性X₃等3项质构参数呈显著负相关(P<0.05),构建回归方程为Y=4.772-0.011X₁-0.017X     

湖南省森林植物园景观质量影响原因研究

以湖南省森林植物园为研究对象,借鉴SBE法对视觉景观质量进行评价,借鉴SD法对景观特征进行评价。通过相关分析建立有关城市森林公园景观质量的评价模型。景观质量评价结果得出植被、水体及路面或广场对视觉景观质量影响较大;景观特征分析了形态丰富度、美感等8个因子对景观质量的影响,建立模型为SBE=-0.58+0.101X₁+0.139X₂+0.257X₃+0.162X₄+0.113X₅+0.181X₆-0.092X₇-0.108X₈,其中,对景观质量影响较大的因子有形态丰富度、美感和生命力,而空间感和变化性与景观质量呈负相关。综合分析结果得出多样化、植被覆盖度高的景观评价较高,人们更为向往自然、幽静的森林景观,森林公园中杂乱无章的植物对景观质量产生消极影响。     

不同形态氮素对红豆杉幼苗生长和生理特性的影响

为研究不同氮素形态配施比例对红豆杉幼苗生长和生理特性的影响,试验以不施氮肥为对照(CK),设置了5个不同形态氮素配比施肥处理,分别为：NO^-₃∶NH⁺₄=100%∶0(N1)、NO^-₃∶NH⁺₄=75%∶25%(N2)、NO^-₃∶NH⁺₄=50%∶50%(N3)、NO^-₃∶NH⁺₄=25%∶75%(N4)、NO^-₃∶NH⁺₄=0%∶100%(N5)。研究了红豆杉生长指标、生物量积累、氮代谢关键酶活性和光合参数的影响。结果表明：施氮可显著促进红豆杉幼苗的生长,提高氮代谢酶活性和光合参数,在NO^-₃∶NH^...     

竹材木质素在细胞壁中的微区分布

对12个月的毛竹和茶秆竹进行了木质素微区分布的研究,实验运用光学显微镜和激光共聚焦扫描显微镜鉴定了木质素的存在,并且利用组织化学染色方法及其可见光显微分光光度计半定量测定竹材纤维?薄壁组织和导管的细胞壁各微区木质素含量。毛竹竹茎各组织细胞壁各微区的木质素含量均大于茶秆竹相应部位的。木质素在各组织中均有分布,其含量因组织类型及其细胞壁不同微区而有差异,其结构中存在愈创木基(G)和紫丁香基(S)两种木质素组成单元。竹壁径向和纤维帽不同位置的木质素含量未有明显的规律性变化。纤维次生壁具有薄厚层交替的多层结构,薄层的木质素含量大于厚层的。     

茶秆竹细胞壁解剖特性以及木质素微区分布

对12个月的茶秆竹进行细胞壁解剖特性和木质素微区分布的研究,运用光学显微镜、激光共聚焦扫描显微镜以及颜色反应鉴定木质素的存在,利用组织化学染色方法及其可见光显微分光光度计半定量测定竹材纤维、薄壁组织和导管细胞壁各微区的木质素含量。12个月时细胞壁全部木质化,木质素在各组织中均有分布,其含量因组织类型及其细胞壁微区不同而有差异。从组织化学染色及可见光吸收光谱图的吸收峰值,说明细胞壁各微区中存在愈创木基(G)和紫丁香基(S)2种木质素组成单元。竹壁径向和纤维帽不同位置的木质素含量未有明显的规律性变化。纤维次生壁具有薄厚层交替的多层结构,薄层木质素含量大于厚层。     

盈江省藤苗木生长对肥料种类和施用量的响应

采用L₉(3⁴)正交设计对造林11和15个月的盈江省藤分别开展施肥试验,施肥后1个月测定苗木的生长指标,包括地径、冠幅、叶片数、叶片长及新叶数,研究不同肥料种类(N:P:K为11:8:6的复合肥、N:P:K为20:5:20的复合肥、过磷酸钙)、施肥量(25 g/株、50 g/株、75 g/株)以及是否施用尿素对苗木生长的影响。结果表明:肥料施用量、是否施尿素以及两者的组合是影响苗木生长的主导因子;不同肥料种类及不同的施用量对苗木各生长指标的影响不同;不同肥料种类对冠幅、叶片长和新叶数具有极显著或显著的影响(P_冠幅=0.017<0.05,P_叶片长=0.004<0.01,P_新叶数=0.038<0.05),不同肥料施肥量则极显著影响地径、冠幅和叶片长(P=0.000<0.01),尿素不同施用量显著影响叶的生长。总体而言,过磷酸钙有利于盈江省藤叶的生长,N:P:K配比为11:8:6的复合肥可增加苗木叶片数和新叶数,尿素对苗木生长具有负效应,不宜施尿素。     

抚顺市天然柞树根径推胸径数学模型的研究

从抚顺市所辖的天然林中随机抽取天然柞树各径级样本共1243株，对其胸径(D1.3)、根径(D0.05)进行围径测量，采用多模型最优法确定6个建模基本方程，通过麦夸特迭代法进行模型参数计算，对建模方程进行评价确定最优模型。通过适用性检验，确定最优模型为D₁₃=a+bD_0.05ln(D^1.5_0.05)+cD²_0.05。     

肉桂多糖的结构分析及抗氧化活性研究

为探讨肉桂多糖的抗氧化活性,将肉桂水提物（CE）除蛋白得到粗多糖,通过纤维素DE-52离子柱和丙烯葡聚糖凝胶S-300进行分级分离得到肉桂中性多糖（CNP）。经凝胶渗透色谱（GPC）法测定CNP的相对分子质量（M_r）,柱前衍生高效液相色谱法测定肉桂中性多糖的单糖组分,通过甲基化法和核磁共振法测定其单糖的连接方式,采用体外化学模型研究CNP对DPPH·和ABTS⁺·的清除作用。研究结果表明：CNP的重均相对分子质量（M_w）为3 630;主要的单糖为葡萄糖;单糖的3种连接方式为1,4,5-Ac₃-2,3,6-Me₃-Glu、 1,5-Ac₂-2,3,4,6-Me₄-Glu、 1,5,6-Ac₃-2,3,4-Me₃-Glu。CNP清除自由基测定结果表明：在质量浓度为2 g/L时,CNP对DPPH·的清除率达到最大为84%,ABTS⁺·的清除率达到60%。虽然CNP对自由基的清...     

密度和行距配置对毛白杨非结构性碳水化合物的影响

为研究非结构性碳水化合物在毛白杨(Populus tomentosa)苗木内的分配规律，提高毛白杨造林效果，以毛白杨新品种‘北林雄株1号’苗木为试验材料，采用双因素完全随机区组设计，设置高(50 000株/hm²,A₁)、中(41 667株/hm²,A₂)和低(31 250株/hm²,A₃)3种育苗密度和3种行距配置(行状配置B₁：行距0.8 m+0.8 m、带状配置B₂：窄行距0.6 m+宽行距1.0m和带状配置B₃：窄行距0.4 m+宽行距1.2 m)，分析育苗密度和行距配置对毛白杨体内非结构性碳水化合物含量和分配的影响。结果表明，低密度带状配置1(A₃B₂)和低密度带状配置2(A₃B₃)条件下，苗木的非结构性碳水化合物含量较理想，A₃B₂的茎、根非结构性碳...     

纤维素模板法增强CuO-ZnO光催化CO2还原性能研究

以漂白针叶木浆(SBKP)为载体，负载CuO-ZnO后炭化，制备得到了纤维素纤维先负载后炭化的CuO-ZnO-生物炭(CuO-ZnO-C_L+C)复合材料。通过扫描电子显微镜(SEM)、电感耦合等离子体质谱(ICP-MS)、X射线衍射(XRD)、双恒电位仪和真空光催化还原CO₂系统，考察了载体负载、炭化的先后顺序对复合材料中CuO-ZnO负载的影响，结果表明：先炭化后负载的生物炭(C_C+L)与CuO、ZnO只是物理混合作用，其表面没有羟基对催化剂进行吸附固定，极易发生团聚，由此制得的CuO-ZnO-C_C+L复合材料的CuO含量没有CuO-ZnO-C_L+C高，CuO-ZnO-C_L+C复合材料的晶型更完整、光电流强度更高、电阻更小，光催化还原CO₂活性更好。以CO得率为考察指标，探讨了Cu²⁺与Zn²⁺物质的量比值、复合材料炭化温度、纤维素纤维直径对所制备的CuO-ZnO-C_L+C     

文化建园的思考——以鲁迅公园改造为例

为使园林建设服务于社会 ,阐明了“文化建园”的基本涵义 ,根据鲁迅公园的现状和历史沿革 ,以鲁迅公园改造为例 ,探讨了文化在公园建设中所包含的内容及发展方向 ,论述了景观、生态、文化、艺术是现代园林的有机组成部分。     

Estimating stem and root-anchorage flexibility in trees

This paper describes a nondestructive method for distinguishing root flexibility from stem flexibility in living trees. It is used here for Sitka spruce (Picea sitchensis (Bong.) Carrière.), but is applicable to any species where the main stem is normally straight and near-vertical. Well-known engineering equations permit the calculation of deflected shape for a vertical cantilever with arbitrary distribution of mass and bending stiffness, when infjected to a lateral force. The equations are used to calculate stem deflections of four Sitka spruce trees for which the stem and branch mass distribution and stem taper have been measured. Free parameters in the mathematical model are a nominal value of Young's Modulus E (assumed uniform and isotropic over the cross section and height of the tree stem) and a root-anchorage stiffness k. The former allows the stem to curve, whereas the latter represents the flexibility of the roots and allows the stem to tilt elastically at ground level. For each of the four trees, the calculated deflection curve is compared with actual deflections measured when the living tree is pulled by a rope at a specified point. By adjusting both E and k, iteratively, a best fit solution is obtained. This provides a simple and effective way to determine both stem stiffness and root hinge stiffness from a single experiment on a living tree.     

Carbon banking: Creating flexibility for forest owners

The focus of forest-based systems for sequestering carbon has largely been on creating permanent stores of carbon on defined areas of land with a single payment to the forest owner for the carbon. In terms of forest management, this focus leads to two outcomes, continuing production of timber if the forest area is sufficiently large to create an effective permanent carbon pool, or a cessation of harvesting if the forest area is too small. In addition, the payment system for carbon is generally based on matching a specific buyer and seller of carbon using a single payment to the forest owner. In combination, both of these factors create a carbon sequestration system that is too inflexible to attract anything but the largest land or forest owners. The paper presents an alternative system for carbon sequestration, carbon banking. Carbon banking treats sequestered carbon in the same way that a financial institution treats capital. In essence, forest owners ‘deposit’ carbon, in exchange for an annual payment, and those who need carbon offsets ‘borrow’ carbon by making an annual payment. The role of the carbon bank is to aggregate deposits of carbon and use these to meet various demands for carbon. There are a number of benefits of this system. It provides an opportunity for small forest owners with different types, age classes and management strategies to participate in carbon markets because payments are based on current carbon sequestered. It also allows participants in the carbon market to receive current value for carbon rather than what effectively represents the capitalised value of the future benefits of sequestering carbon, thus removing some uncertainty about locking into the wrong value for carbon.     

Handbook of the insects and other invertebrates of Hawaiian sugare cane fields.

Ohne Zusammenfassung     

Predation on invasive cane toads (Rhinella marina) by native Australian rodents

Journal of Pest Science - The success of an invasive species can be reduced by biotic resistance from the native fauna. For example, an invader that is eaten by native predators is less likely to...     

Mechanical relaxation processes due to sugars in cane (Arundo donax L.)

The storage modulus and the mechanical loss tangent of untreated, extracted, and sugar- impregnated canes (Arundo donax L.) were measured over a temperature range of –150° to 0°C at low frequencies. Two relaxation processes, labeled and , were detected in the ranges –60° to 0°C and –120° to –100°C, respectively. The and processes shifted to lower temperatures with increasing moisture content. The process was detected only in the canes containing sugar. The magnitude of its loss peak increased with an increase in sugar content. It was speculated that the process was due to some interactive molecular motions of the adsorbed water and sugar. The process, detected in all of the canes, was attributed to the motion of the adsorbed water in the amorphous cell wall substances.     

雷州半岛蔗区宿根蔗低产原因及对策

甘蔗宿根栽培具有省工、省种、省成本的优点及早生快发，早熟高糖，利于糖厂提早开榨，增产潜力大的优势，是发展甘蔗生产的重要栽培制度。广东省雷州半岛宿根蔗面积约占种蔗面积％～40 ％，由于各种原因，仅少数宿根蔗比新植蔗增50产，而大部分都比新植蔗减产％～％，严重的2030减产％以上。据调查统计，新植蔗平均产蔗量6075 t/hm2，而宿根蔗只有～4560t/hm2。以至宿根蔗的比重和年限出现逐年缩小的趋势。因此，找出宿根蔗低产原因，是解决雷州半岛宿根蔗高产问题的关键。　1宿根蔗低产原因分析经调查研究，宿根蔗低产主要原因是有效茎…     

An evaluation of methods used to cull invasive cane toads in tropical Australia

To identify cost-effective ways to control invasive species, we need to evaluate alternative methods. The invasion of tropical Australia by cane toads (Rhinella marina) has killed many native predators, prompting efforts to cull adult toads. We analyzed a dataset on >?17,500 toads killed by government-employed teams from 2005 to 2008, using a range of methods (incidental captures, targeted searches, traps) as well as records of toads found as road kills. The culling occurred in the northwestern part of the Northern Territory, moving west as the toad front expanded into Western Australia. Both season and method affected rates of capture and demographic attributes (sex ratio, proportion of adults) of the culled anurans, with a strong interaction between these factors. Most methods were more effective during and after the seasonal monsoons (when moist conditions facilitated anuran activity), but that seasonal variation was greater for numbers of toads found on the roads than captured in other ways. Juvenile toads and adult female toads constituted higher proportions of total captures in the Early Dry than in other times of year, reflecting seasonal breeding. Traps caught a higher proportion of adult female toads than did other methods, but overall had low capture rates. Rates of range expansion by toads were similar before, during and after the culling effort, suggesting that removing adult toads did not affect the speed of the invasion. Nonetheless, culling adult cane toads may be effective in some situations (“island” populations, extralimital translocations), and results from this program may be valuable for future toad-control efforts.     

孟加拉吉大港市藤家具企业的经济效益分析

采用分阶段抽样方式对大港市藤家具企业的经济效益进行调查.根据总投资将企业分为大型、中型和小型三类.大部分的企业(55%)已有40-50年的历史,仅有18.33%的企业历史超过50年.在小型和中型企业中,具有大学毕业文凭的企业家只占8.33%, 而大型企业的大学毕业者占18.33%.大部分企业(45%)属于小型企业,66.67%的工人经过技术培训.7种商品是藤类制品并有16种尺寸,如沙发(45 cm ( 45 cm, 50 cm ( 50 cm and 55 cm ( 55 cm), 配套餐桌(4把椅子,1个桌子,或6把椅子1个桌子),床(1 m ( 2m, 1.3 m ( 2.3 m and 1.5 m ( 2.3 m),椅子(45cm(45cm and 50cm(50cm),摇椅(大、中、小)等.在所有大型、中型和小型企业中,以生产椅子最多,床最少.大型藤家具企业的总净收益和收益造价比(1:16)最高.     

Shrinkage of cane (<Emphasis Type="Italic">Arundo donax</Emphasis>) I. Irregular shrinkage of green cane due to the collapse of parenchyma cells

Shrinkage of green cane (Arundo donax L.) was measured during air-drying at room temperature. The cane began to shrink at 150% moisture content due to a remarkable collapse of parenchyma cells. The collapse recovered after boiling in water, but more serious collapse (recollapse) was induced by the following drying. On the other hand, the collapse recovered almost completely after steaming with saturated water vapor at 92°–96°C without recollapse. By comparing the thickness of cane specimens before and after steaming, the degree of cell collapse remaining in dry cane was evaluated. When the green cane was frozen prior to drying, the degree of collapse was reduced whereas the drying rate remained unchanged. The effect of prefreezing was interpreted as the generation of air bubbles in the cell lumen which hinder the effective loading of liquid tension on the cell wall. Even when the cane was carefully dried using a conventional method used by reed manufacturers, the degree of collapse was very large and it increased with elevating internode position.