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141.
自2018年正式提出“新基建”一词后,新基建成为实现经济高质量发展的重要一环,同时,物流业也在新基建推动下焕发出生机和活力。从效果看,新基建政策有利于饲料企业提升供应链和物流服务水平,有利于饲料企业物流信息化、智能化转型升级,有利于饲料企业物流数字化建设。但饲料企业借助新基建政策助力智慧物流网络建设时,一方面,注意补短板,地区之间的不平衡发展及企业之间缺乏合作将影响智慧物流的全局建设|另一方面,致力于从物流园区建设、仓储建设、干线运输建设3个方面来夯实智慧物流建设基础。
[关键词]新基建|饲料企业|智慧物流|智能化|数字化 相似文献
142.
This study evaluated the protection effectiveness of alcohol-borne reagents for the green color of ma bamboo (Dendrocalamus latiflorus Munro) and moso bamboo (Phyllostachys pubescens Mazel). The results show that the types and concentrations of alcohol-borne reagents, the kinds of solvent, and the conditions
of treatment greatly affected the green color of these two bamboo species. Without alkali pretreatment, an excellent green
color protection (a* = −14.5) was obtained when the ma bamboo culms were treated with 0.5% methanol-borne copper chloride (CuCl2) at 60°C for 30 min. Similar results were also obtained when ma bamboo culms were treated with 0.5% methanol-borne copper
nitrate [Cu(NO3)2] at 60°C for 2 h (a* = −13.5). For moso bamboo, an attractive green color in the bamboo culms was achieved by treating the specimens with 1%
methanol-borne copper acetate [Cu(CH3COO)2] at 60°C for 30 min. The a* value of treated specimens was −13.3. In addition, results demonstrated that ultrasonic treatment was more effective on
green color protection than conventional water bath treatment. When moso bamboo was treated with 1% copper acetate at 60°C
in an ultrasonic bath for only 15 min, a remarkable green color with an a* value of −13.6 was obtained on the bamboo epidermis. 相似文献
143.
This study examined the hypothesis that incorporation of Gliricidia sepium (Jacq.) Walp.) (gliricidia), a fast-growing, nitrogen-fixing tree, into agroforestry systems in southern Malawi may be used
to increase the input of organic fertilizer and reduce the need for expensive inorganic fertilizers. The productivity of maize
(Zea mays L.), pigeonpea (Cajanus cajan L.) and gliricidia grown as sole stands or in mixed cropping systems was examined at Makoka Research Station (latitude 15°
30′ S, longitude 35° 15′ E) and a nearby farm site at Nazombe between 1996 and 2000. Treatments included gliricidia intercropped
with maize, with or without pigeonpea, and sole stands of gliricidia, maize and pigeonpea. Trees in the agroforestry systems
were pruned before and during the cropping season to provide green leaf manure. Maize yields and biomass production by each
component were determined and fractional light interception was measured during the reproductive stage of maize. Substantial
quantities of green leaf manure (2.4 to 9.0 Mg ha−1 year−1) were produced from the second or third year after tree establishment. Green leaf manure and fuelwood production were greatest
when gliricidia was grown as unpruned sole woodlots (c. 8.0 and 22 Mg ha−1 year−1 respectively). Improvements in maize yield in the tree-based systems also became significant in the third year, when c. 3.0 Mg ha−1 of grain was obtained. Tree-based cropping systems were most productive and exhibited greater fractional light interception
(c. 0.6 to 0.7) than cropping systems without trees (0.1 to 0.4). No beneficial influence of pigeonpea on maize performance
was apparent either in the presence or absence of gliricidia at either site in most seasons. However, as unpruned gliricidia
provided the greatest interception of incident solar radiation (>0.9), coppicing may be required to reduce shading when gliricidia
is grown together with maize. As pigeonpea production was unaffected by the presence of gliricidia, agroforestry systems containing
gliricidia might be used to replace traditional maize + pigeonpea systems in southern Malawi.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
144.
通过对山西省偏关县退耕还林、加快后续产业发展主要做法的调查。认为柠条先行、灌草结合、兴林促牧是一条改善生态、发展经济、农民增益、实现“三嬴”之路。推进灌草结合造林模式,不仅缓解了林牧矛盾,巩固了退耕还林成果,也为加快农村产业结构调整、推动农民在退耕还林后发展商品型畜牧业创造了有利条件。 相似文献
145.
146.
相对于我国退耕还林工程,农区林业的优势在于:经营模式多样,农民经营风险低,行为自主性较强,为农村剩余劳动力(特别是妇女)提供更多就业机会,政府干预较少。我国退耕还林工程应该学习农区林业的成功经验,从政策上做出调整,建立促使农民积极参与的激励机制,并减少政府的直接干预,以降低政策成本。 相似文献
147.
This paper examines the first-best instruments for biodiversity maintenance in commercial boreal forests when landowners behave either in Faustmannian or Hartmanian way. Using an extended Hartman model, we show that biodiversity conservation requires both prolonged rotation age and leaving retention trees. While the former promotes some old growth species, the latter create new structural elements of decaying and dead wood, which can sustain a variety of saprolyxic species. A fully synchronized combination of retention tree subsidy and tax instrument is needed both to lengthen the privately optimal rotation period and to provide an incentive to leave retention trees. Using Finnish data we illustrate empirically the sizes of instruments. When combined with a harvest tax, the retention tree subsidy is 1000 and 750 € in the Faustmann and in the Hartman model, respectively. When used with a timber subsidy or a site value tax, the retention tree subsidy is 1700 €/ha in both models. The harvest tax rate varies over the range 40–65% in the Faustmann model and 20–40% in the Hartman model, while timber subsidy is between 0.5–1.0% and site value tax is about 1.75%. 相似文献
148.
日本龟蜡蚧在枣树上的发生与危害 总被引:3,自引:0,他引:3
1996年8月 ̄1997年6月,在陕西大荔县八鱼乡西营村和蒲支县平路庙乡直杜村调查了日本龟蜡蚧在枣树上的分布与危害。结果表明,单叶幼虫数随枣树受害程度的增加而增加,单果重随枣树爱害程度的增加而减少,越冬雌虫的危害造成每股的抽吊数减少,吊长显著变短,每吊的刺树数减少,幼虫和雌成虫在树冠上的分布是阳面(南面)大于阴面(北面),其中树冠中部虫量分布的最多。 相似文献
149.
150.
Anthony S. Davis Douglass F. Jacobs Kevyn E. Wightman Zonda K. D. Birge 《New Forests》2006,31(2):293-303
Bareroot hardwood seedling production involves intensive soil management. To increase soil organic matter (OM), nurseries
commonly grow a cover crop for 1 year after every 1–2 year of seedling production. Raising soil OM levels can also be achieved
through addition of soil amendments. We studied the influence of chicken manure (CM) and composted leaf, tree, and lawn trimmings
(Cp) on soil properties and morphology of green ash (Fraxinus pennsylvanica Marsh.) and northern red oak (Quercus rubra L.) seedlings. CM was applied at 725, 1450, or 2900 kg ha−1 (CM725, CM1450, and CM2900, respectively) and Cp was applied at 200 m3 ha−1. Addition of CM and Cp significantly raised soil OM levels and altered soil chemical properties compared to the control (Ctrl).
Root-collar diameter increased with addition of CM1450, CM2900, or Cp compared to CM725 or Ctrl plots for northern red oak,
but was largest in soils amended with CM2900 for green ash. Conversely, height was greatest with addition of CM725 for northern
red oak, but green ash seedlings were shorter in Ctrl plots than in all amendments except for CM725. Root volume of green
ash and northern red oak seedlings was positively influenced by addition of CM or Cp. Seedling responses to nursery soil amendments
vary with different forms and amounts of OM. Benefits to seedling growth through application of appropriate materials in the
proper balance can improve seedling morphological quality and positively influence soil chemical properties. 相似文献