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1.
U. Y. Anele O. M. Arigbede J. A. Olanite I. O. Adekunle A. O. Jolaosho O. S. Onifade A. O. Oni 《Agroforestry Systems》2008,73(2):89-98
A study was carried out to evaluate the growth parameters and nutritive qualities of Moringa oleifera, Millettia griffoniana and Pterocarpus santalinoides. The main objective of the study was to assess the potential of the MPTS in supplementing the feed of ruminant animals during
the dry season when grasses are scarce and their quality generally fall short of animal requirements. Leaf samples were randomly
collected from the trees for estimation of the proximate composition, neutral detergent fibre, acid detergent fibre and gas
production using the in vitro technique. Samples were collected three times to represent seasonal variations as follows: November:
Early Dry; February: Mid Dry and April: Late Dry seasons. Gas production was recorded at 3, 6, 9, 12, 15, 18, 21, 24, 48,
72 and 96 h of incubation. Mortality rate was less than 5%. M. oleifera recorded the best overall growth respectively followed by P. santalinoides and M. griffoniana. P. santalinoides and M. oleifera retained more leaves in the dry season than M. griffoniana. The dry matter (DM) and ether extract (EE) contents of the MPTS were significantly (P < 0.05) affected by seasons and plant species while there were significant (P < 0.05) species effects on the CP and ADF values. The gas production values and the fermentation parameters indicated the
presence of potentially degradable nutrients in the MPTS, which underscores the importance of the tree species as sources
of nutrient for ruminant animals during the dry season. 相似文献
2.
“云南松胶合板材、纸浆材种源选择”是多性状综合评选，把生长与多用途选育结合。本材料取自1981年营造的种原试验林和部分天然林内，共选取13个产地，38件试材，作木材解剖，物理性能和化学成分含量等测定．经分析各种源间木材的各理化性状的差异达权显著水平．并获得与胶合板、纸浆材关系较密切的是种源间年均材积生长量（X1）、树干纹理通直度（X2）、木材密度（X3）、管胞长（X4）、纸浆得率（X5）．根据性状遗传力（H2）及它们的经济重要性估算权重值（W），建立“两材”的种源综合选择指数方程：①I板＝214．0571X1＋0．29859X2＋0．37736X3和②I纸＝214．0571X1＋0．06212X4＋0．39278X5。按①和②综合选择式，评选出乐业、红河、双柏、双江、石屏、开远、富宁等8～10个适于“两材”高产优质种源，材积平均遗传增益达47．3％，树干纹理通直率达87％～98％；单位面积上木材干物质重提高18．0％～49．6％，纸浆得率18．4％～49．7％。胶合板的抗压、抗弯强度等力学指标均有提高，胶合强度1．97～2．58MPa＞0．8MPa（GB指标），手抄纸的耐破度，裂断长，撕裂度均达到观指标。使“两材”的种源选择建立在遗传型的基础上．同时为各生态区提出供选择的丰产种源。 相似文献
3.
Mechanised harvesting operations are becoming more prevalent in South Africa, with the realisation that motor- manual and manual harvesting operations pose significant health and safety risks to workers. However, the potential damage caused by single-grip harvester feed rollers and delimbing knives on the log surface during debranching and debarking of eucalypts pulp logs may negatively affect fibre recovery as opposed to manually debarked logs, which show little or no log surface damage. Compared with manual debarking, this study investi- gated the influence of two mechanised debarking treatments on wood fibre loss on eucalypt log assortments debarked by harvester head feed rollers and delimbing knives. The two mechanised debarking treatments consisted of three and five feed roller passes along the stem surface. In addition to quantifying the magnitude of this fibre loss, a financial evaluation was done to calculate the value of these losses. The three- and five-pass debarking treatments caused significant fibre losses of 1.425 green tonnes per hectare (gt ha?1) and 2.275 gt ha?1, respec- tively, as opposed to manually debarked logs, which produced no fibre losses. Wood fibre losses in terms of total potential (or available) wood mass for three- and five-pass mechanically debarked trees were 1.06% and 1.70%, respectively. These represent a fibre value loss of R441.75 ha?1 and R705.25 ha?1 for three- and five-pass operations, respectively. For the 6.48 million gt y?1 currently mechanically debarked for the South African pulp and paper industry, this equates to fibre value losses of R21.36 million and R34.10 million annually for three- and five-pass operations, respectively. 相似文献
4.
对印度亚热带潮湿气候中的多种用途树叶作为草料的质量评价(英文) 总被引：1，自引：0，他引：1
多种用途树种和灌木在农业系统中有重要的作用,在减少饲料供求矛盾和补充世界各地饲料赤字,提高动物生产力方面有很大的潜力。同时,评价草料各种营养特性,利于生产定量平衡的饲料。评价12种多种用途树种(Acacia auri-culiformis,Albizzia procera,Dalbergia sissoo,Gliricidia macu-lata,Leucaena leucocephala,Samanea saman,Azadirachta in-dica,Eucalyptus hybrida,Gmelina arborea,Michelia champaca,Morus alba,和Tectona grandis)的树叶的营养特性,其中分别包括6种豆科和非豆科树种,指标包括:常规成分,细胞壁成分,总鞣质含量,大量(Ca和P)与微量元素(Fe,Cu,Zn,Mn和Co)含量,干物质体外消化率与有机物消化率以及代谢能量值。结果表明上述各参数都有明显的差异。有机物,粗蛋白质含量,石油醚提取物总量,粗纤维含量,无氮浸出物,总灰分的平均值分别为:(92.02±0.30)%,(16.00±0.74)%,(3.05±0.13)%,(18.97±1.07)%,(54.00±1.12)%和(7.98±0.30)%。豆科树种较非豆科树种有更高的粗蛋白质含量(18.30%和13.70%)。细胞壁成分中的中性洗涤纤维素,酸性洗涤纤维,半纤维,纤维素,酸性木质素含量平均值分别为:(52.48±1.05)%,(31.72±0.97)%,(20.76±0.88)%,(16.97±0.70)%和(9.57±0.62)%。总鞣质含量为(4.22±0.32)%。Ca与P之比合理,多种树种叶中Fe和Mn含量丰富,P,Cu,Zn和Co水平低于标准水平含量。干物质体外消化率与有机物消化率平均值分别为(48.96±1.30)%和(50.69±1.36)%。代谢能量值为(6.95±0.11)MJ·kg-1。粗蛋白质含量与干物质体外消化率与有机物消化率和代谢能量值成正相关;而这三个参数与中性洗涤纤维素,酸性洗涤纤维,和酸性木质素含量成负相关。结果表明:银合欢可作为优良饲料的树种,因为它具有最高的干物质体外消化率与有机物消化率以及代谢能量值(65.20%,67.66%和7.95MJ·kg-1),而Gliricidia maculata,Morus alba,Azadirachta indica,Dalbergia sissoo和Samanea saman可做较好类型饲料的树种,其它树种做饲料质量差。 相似文献
5.
The effects of drought stress on growth and dry matter partitioning of seven provenances of Parkia biglobosa were assessed in a nursery experiment. Three different water regimes were applied: soil high, medium and low water content (HWC, MWC and LWC) corresponding respectively to 100, 75 and 50 % of field capacity. A split-plot experimental design was applied with the provenance as main plot and the water regime as sub-plot, replicated three times. Each provenance was represented by 30 seedlings in each replication, corresponding to three test periods with ten seedlings each (6, 12 and 18 months after water stress started). There were significant interactions between provenance and water regime for survival rate and the relative growth rates of diameter and height. After 18 months, the dry matter mean was 20.00 ± 0.65 g for the HWC regime, 11.50 ± 2.90 g for the MWC regime while all plants in the LWC regime died. After 6 months, the accumulated water use efficiency (WUE) showed significant differences between water regimes, but not between provenances. Seedlings from the LWC regime showed higher WUE than those from the MWC regime. However, the HWC regime displayed the highest mean value of WUE. Despite differences between provenances, it was not possible to clearly separate them according to the geographical position or climatic parameters, based on the growth performance or both fresh to dry weight and shoot to root dry weight ratios. 相似文献
6.
利用不同地区5个典型马尾松种源，布置3种P水平的盆栽实验，研究马尾松应对低P胁迫时根系形态和干物质分配特征的种源差异。结果表明，P素胁迫的加重导致马尾松干物质积累量的下降和一些根系参数的减小，但植株地下部分的干物质分配量和根系形态参数的相对值却显著增加。低P胁迫下，种源间干物质积累量(包括植株各部分和总的积累量)和侧根数等根系参数差异显著。低P下干物质生产能力较强的福建武平种源对磷肥的敏感性较低，广东信宜和浙江淳安种源次之，类似于大田和水培实验结果。遗传相关分析揭示：侧根发达、须根数量多的种源干物质生产能力强。根体积、侧根数、侧根总长、须根总数等可作为筛选马尾松耐低P种源的有效指标。 相似文献
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9.
通过对受拉缘蝽不同程度为害的卵叶小蜡叶片的单宁、黄酮、总酚含量的测定,结果表明:受害的卵叶小蜡叶片的单宁含量随着拉缘蝽若、成虫为害程度的加重而发生变化,在受害初期显著增加,但随着为害程度的加重,而呈逐渐下降的趋势;受害卵叶小蜡叶片中黄酮含量随着受害程度的加剧,呈先上升、而后再下降的特点;叶部总酚的含量随着受害程度的不断加重,总酚的含量呈现上升的趋势。说明卵叶小蜡应激反应的过程是一种随着受害程度的不同而不断变化的动态过程。 相似文献
10.
Development of a method for sorting picea abies pulp wood with respect to basic density 总被引：1，自引：0，他引：1
《Scandinavian Journal of Forest Research》2012,27(1):65-69
The basic density of pulp wood can be used to convert green volume to dry weight, and as an indicator of the fibre quality. Because the methods for measuring basic density are cumbersome, a practical, on‐line method for sorting Norway spruce pulp wood with respect to basic density was developed. The relationship between mean annual ring width and basic density was used to sort the pulp wood. Brief visual inspection could separate piles of logs with different mean annual ring widths from each other with an acceptable precision. The resulting classes had significantly different mean basic densities (380, 400 and 434 kg m?3). Means of other properties, such as juvenile wood content, heartwood content, and dry matter content, also differed among classes. 相似文献
11.
S. De Smedt K. Alaerts A. M. Kouyaté P. Van Damme G. Potters R. Samson 《Agroforestry Systems》2011,82(1):87-97
We analyzed the phenotypic variation of baobab (Adansonia digitata L.) fruits from Mali to define the domestication potential of this species. 269 trees, selected from 10 provenances distributed
along a rainfall gradient, were characterized. Five fruits were sampled from each tree. Total individual fruit weight was
partitioned into shell, pulp, and seed weight. Ratios were calculated between pulp + seed and total weight, and between pulp
and seed weight. For all the measured fruit traits, we detected significant differences between provenances, as well as between
trees from the same provenance. Assuming that the measured traits are under genetic control, the latter facts indicate that
there are considerable opportunities for tree selection on a local scale. However, candidate plus trees with specific properties,
e.g., extremely high pulp or seed weight, were found only in some locations. Mean pulp yield per fruit might be considerably
increased by selecting the 5% trees with the highest pulp weight (mean: 45 ± 1 g, best 5%: >100 g). The same might be true
for seed production (mean: 71 ± 2 g, best 5%: >150 g). Also the ratio between pulp and seed weight can be an important fruit
characteristic for selection: in fruits with a low ratio, relatively more pulp sticks to the seeds when separating the two
fruit parts by grinding, and thus more pulp will be lost for further processing. We identified several trees with a high pulp
weight combined with a high ratio between pulp and seed weight. It is concluded that there is considerable phenotypic variability
in traits of baobab fruit in Mali, offering opportunities for cultivar selection. 相似文献
12.
设计了低磷(5 mg·kg-1)和高磷(180 mg·kg-1)两个磷素处理水平的盆栽实验,研究马褂木6个代表性种源的磷效率特性差异及其相关性状的关系.结果表明,马褂木种源磷效率差异较大,其值变化在15.4%～38.9%.结合考虑种源对磷肥的敏感性及在不同磷素水平下的生长表现,认为湖南通道为耐低磷型或高磷效率的优良种源,而贵州黎平和湖南邵阳则分别为磷素中等敏感型和磷素敏感型优良种源.研究发现,马褂木种源磷效率与磷素的吸收效率有关,而与磷素的利用效率相关性较小.低磷水平下种源的干物质生产能力可很好地指示磷效率的大小.高磷效率的种源在磷胁迫条件下具有干物质积累量高、叶片宽大、数量多、须侧根发达等特点,而低磷效率种源的干物质积累量低、叶片窄小、须侧根不发达,并呈现缺磷症状. 相似文献
13.
收集邓恩桉全天然分布区种源及其家系进行引种试验,以酷热严寒等极端天气的抗逆性表现,评估其对气候的适应性;采取多点试验联合分析法,回归分析各处理所有地区的生长信息,评估其对不同立地环境的适应性,建立起各种源、家系的生长模型。各种源性状优良,种源间差异不显著,整个天然分布区均为优良种源区;选出最佳种源地12个;优良家系46个,平均34.16 m3·hm-2·yr-1,径高比≥1：90、个体变异≤15%,木材材质好、造纸得浆率49%;家系间差异极显著,优良家系的遗传增益显著大于最佳种源;选优良单株250株,其中68株3年生时始花。区组间差异极显著,大多数种源、家系与地区的交互作用极显著,回归系数大,对生长环境敏感,要有好的立地条件才能发挥其速生特性。 相似文献
14.
在南、中、北亚热带地区三片九年生马尾松种源试验林中(广西南宁、江西安福、浙江鄞县),采集9个代表性种源试样,测试28项包括木材构造、物理和化学的性状,进行种源间比较选择,结果是:①经试验点内及多点方差分析,各性状种源间差异远大于种源内个体间差异,且种源与试验点间存在互作。②主要造纸经济性状(管胞宽、长宽比、双壁厚、腔径和壁腔比等)遗传力估值均大于0.6,受强度的遗传控制。③材性与生长性状间相关分析表明,在马尾松速生地区作高、径性状的正向选择会导致种源或个体的管胞长宽比、晚材率和壁腔比下降,管胞宽度及腔径增大,这为间接选择提供依据。④取与造纸性能关系紧密的11项木材性状,综合选择出高州、宁明、吉安和德江等优良种源。 相似文献
15.
Two experiments evaluated variations in feed value among Calliandra calothyrsus provenances. In Experiment 1, edible forage
production of four provenances were evaluated at Ibadan, southwestern Nigeria over a 2-year period in three seasons: main-wet
(April–August), minor-wet (September–November) and dry (December–March). Forage samples from the main-wet and dry seasons
were incubated for 6, 12, 48, 72 and 96 h in rumen-fistulated steers to estimate in sacco dry matter (DM) and nitrogen (N)
degradation characteristics. In vitro gas production was estimated over 3, 6, 12, 24, 48, 72 and 96 h of incubation. In Experiment
2, DM degradation characteristics of 14 provenances of C. calothyrsus planted on an acid soil in Yaounde, Cameroon, were evaluated.
Data were subjected to cluster analysis for grouping, and the 14 provenances were placed into four distinct cluster groups.
Based on the potential extent of DM and, N degradation and gas production characteristics in Experiment 1, the four provenances
of C. calothyrsus were classified into three forage quality groups: high (ILCA 16310), medium (ILCA 14891, ILCA 15166) and
low (NFTA 896). In Experiment 2, using the extent of DM degradation as a forage quality index, C. calothyrsus provenances
in clusters 3 and 4 (namely: 51/92, 11/91, 13/91, 45/92, 10/91, 15/91, 18/91, 134/91, 12/91, 62/92), were relatively higher
in quality than their counterparts in clusters 1 and 2. The results suggested the existence of intra-species variation among
the provenances, and confirmed earlier observations that forage quality of C. calothyrsus could be improved through provenance
evaluation.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
16.
One-year-old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and lodgepole pine (Pinus contorta Dougl.) seedlings were grown for 17 weeks in 100-cm deep, 7.8-liter containers. Two Douglas-fir provenances, one from a wet and one from a dry site in coastal British Columbia, and two lodgepole pine provenances, one from a wet and one from a dry site in interior British Columbia, were grown in wet (522% water content) or dry (318% water content) peat/vermiculite soil in a factorial design. Each container was sealed so that water loss occurred only through the seedling. Five harvests were made at three to five week intervals and water use, dry matter increment, root length and root weight were determined at each harvest. Stomatal conductance and shoot water potentials were measured during the last 12 weeks of the experiment. Lodgepole pine seedlings had greater dry matter production, water use, stomatal conductance and new root length than Douglas-fir seedlings. New root weight of lodgepole pine seedlings exceeded that of Douglas-fir seedlings during the last five weeks of the experiment, and specific root length (root length per unit root weight) of new roots was higher for lodgepole pine seedlings throughout the experiment. Douglas-fir seedlings showed higher water use efficiency (WUE) than lodgepole pine seedlings, and both species showed higher WUE in the dry soil treatment. Douglas-fir seedlings had lower water potentials and higher water uptake rates per unit of new root length than lodgepole pine seedlings, although water uptake rates per unit of root dry weight showed little difference between species. Soil water treatment influenced specific root length of new roots, water uptake per unit of new root length, and WUE in Douglas-fir seedlings more than in lodgepole pine seedlings. 相似文献
17.
在柿饼制作过程中,本研究目的在于监测不同条件下柿皮和柿果中有效成分的变化。结果表明,柿果加工成柿饼后,含糖量从1.31 mg·g^-1增加到2.65 mg·g^-1,增加102.14%。而对于鲜柿中的单宁、总黄酮、总酚、Vc等成分,在柿饼中的含量则大幅下降,分别降低了94.06%、83.30%、37.26%、99.92%。同时,通过对柿子皮提取物进行分离分析,发现柿皮中Vc含量达到165.71 mg·(100g)^-1,是果肉的2倍多;总糖、总酮和多酚的总含量约占柿皮提取物的65%,使得柿皮提取物具备明显的体外抗氧化活性。 相似文献
18.
A trial set-up with methods for sampling, treatment and analysis of small wood chips are presented in this paper, to determine important wood and fibre properties, like basic density, dry density, volume swelling of wood, Kraft pulp yield, fibre length, fibre coarseness, fibre width, lumen width and fibre wall thickness. The required time for one sample is about 1.5 man-hour, but this requires relatively larger series and trained personnel. Acceptable measurement accuracy is achieved when the volume of the wood sample is at least 1.5 ml, except that of wood volume swelling. To gain acceptable measurement accuracy for volume swelling, the wood volume should be increased to at least 3 ml, and preferably more than 5–6 ml per sample. The level of pulp yield and wood density do not show a significant effect on the measurement accuracy for fibre cross-section dimensions. Fibre coarseness, on the other hand, has a significant influence on these accuracies. A double measurement of fibre coarseness will improve the accuracy to an acceptable level. The method presented here may, together with information about trees and growth locations, form the basis for greater insight into the mechanisms involved in development of wood and fibre properties in trees, which in turn may provide better control and utilisation of wood for pulp and paper production.Abbreviations CWD cell wall density in dry wood=1500 kg/m3 - Ww dry weight of wood (kg) - Vmax green (wet) volume of wood (m3) - Vmin dry volume of wood (m3) - BD basic wood density (kg/m3) - DD dry wood density (kg/m3) - VS maximum volume swelling of wood (%) - Wp dry weight of pulp (kg) - PY pulp yield (%) - C fibre coarseness, the average weight of a unit length of fibre (g/m) - CL average chip length (mm) - CWT average cell wall thickness (m) - FW average fibre width (m) - l average native fibre length in solid wood - L chip length - lc average fibre length in wood chip (mm) - Lc length-weighted fibre length in wood chip (mm) - lw native average fibre length in wood (mm) - Lw native length-weighted fibre length in wood (mm) - LW average lumen width (m) - llw average native fibre length, length weighted, in wood - X average fibre length in chip - Xlw average fibre length, length weighted, in chip 相似文献
19.
Eight woody fodder species adapted to the highlands of Rwanda were evaluated in terms of dry matter intake in one experiment. Animals were offered a daily diet comprising 4.0 of fresh matter of Setaria splendida grass supplemented with or without one of the eight fodder species tested. In all cases, total daily feed intake was increased by the addition of woody fodder. Daily intake of the woody fodder was high for Acacia koaia, Mimosa scabrella and Acacia koa at 43.7, 42.6 and 41.9 g/kg BW0.75, respectively. The dry matter intake of the other five species (Alnus acuminata, Chamaecytisus palmensis, Hagenia abyssinica, Acacia mearnsii and Acacia melanoxylon) ranged from 18.9 to 30.1 g/kg BW0.75 per day. In another experiment, a basic daily diet of 4.0 kg of fodder (in fresh weight) was given to each animal. This ratio comprised S. splendida supplemented with M. scabrella and incorporated at 0 (control), 45% and 66% (fresh weight basis) of the total daily diet. Improved weight gain was obtained when setaria was supplemented with M. scabrella with daily weight gain of 31, 47 and 51 g/animal for 0, 45 and 66% M. scabrella, respectively. 相似文献
20.
D. M. Phiri B. Coulman H. A. Steppler C. S. Kamara F. Kwesiga 《Agroforestry Systems》1992,17(2):153-158
The effect of browse supplementation on maize husk (Zea mays) utilization by goats was studied in a 12 week feeding and 2 week digestibility trial. Twenty-four goats were stratified
according to their weight, and then randomly allocated to four treatments. Browse supplementation significantly increased
(P < 0.05) the total dry matter intake, diet dry matter digestibility and diet organic matter digestibility (P < 0.05) but
did not have any significant effect on acid detergent fibre digestibility (P > 0.05). The browse supplemented goats gained
more weight than the non browse supplemented goats. 相似文献