造林

Department of Forestry, is primarily dedicated to teaching and research including forestry include: Biometry, Ecology, economics and social science, entomology and pathology, plant breeding and genetics, soils and hydrology, silviculture, social forestry and agroforestry, tree physiology, urban forestry, and wood science.

林业系主要致力于林学的教学与科研，学科领域包括生物统计学、生态学、经济学和社会科学、昆虫学和病理学、植物营养和遗传学、土壤和水文学、造林学、社会林学和农业森林学、树生理学、都市林产和木材科学等。

In different height seedlings,4.0m and 4.5m are sensitive to the grafting,especially to the tree from 4.0m seedling in height,of which main trunk and diameter breast-high might be largest after two times grafting,which can decrease the cost of plantation establishment and increase the economic performance.

在不同初植苗高的泡桐中，4.0m、4.5m的苗高对接干反应较为明显，尤其是4.0m高的苗木通过一次和二次接干后，其胸径和全高生长量都达到最大，其为降低泡桐造林成本，提高经济效益有一定的指导意义。

The growth and physiology characteristics for two-year-old saplings of 7 Catalpa spp. planted in upland area were studied.

对低山丘陵地造林的7个品种楸树2年生幼树的生长和生理特性进行了研究。

The model is used to analyze and predict runoff changes caused by clear-cutting or afforestation.

计算结果表明：皆伐使径流量和洪蜂增大，造林使之减小，而当雨量非常大时，这些效应几乎不存在。

Therefore, with some engineering and biological measures, after some pioneer trees are planted in extremely degraded tropical areas,the pioneer forest should be reformed by multilayer and multispecies broad leaved mixed forest in time, wihich could accelerate the development of artificial forest into local climax community.

因此，对于极度退化的热带丘陵台地区，在一定工程和生物措施基础上，用先锋绿化树种造林成功后，及时用多层多种的阔叶混交林改造原有先锋林，可以加速人工林向地带性植被类型演替。

Our study regarded Pear and Aids Apricot tree which be used to develop afforestation by water-harvesting in Semi-arid Region on Loess Plateaus as experience forest. In the case of water-retaining agent, we study the physical effect of water-retaining agent on soil water shifting balance and water use efficiency through soil-water-atmosphere conium system.

本研究以黄土半干旱区集水造林的杏树和梨树为试验林分，采取以保水剂为中心的综合保水技术，运用土壤—植物—大气连续体理论和土壤物理学理论，系统地研究了保水剂对土壤水分动态及其利用效率的影响，得到如下主要结论： 1。

All plantation activities must be took along contour line.

所有造林活动必须沿等高线进行。

For stabilizing theeffect of Hippophae in continueing growth and N2 fixation for longer peried,coppice to Hippophae at 5 years interval is necessary.

为了保证沙棘能持续稳定地固氮、增氮，保持混交林的合理结构和稳定性，剪伐更新是必要的，一般以5年为宜，更新的当年和次年其结瘤固N能力即恢复到造林后的3-4年的水平。

The proper planting density should be 1 m × 0.3 m and 0.3 m × 0.3 m for land under broadleaf crown and shady droughty land respectively. If the havelock equipment in field was used, seedlings with 15-20 cm for height and 0.30 cm for diameter should be selected for cultivation, with the density and transmittance being 0.3 cm × 0.3 cm and 50% respectively.

林冠下栽植和山垅旱地造林的适宜密度分别为1 m×0.3 m和0.3 m×0.3 m；若利用农田庇荫设施栽培，应选用苗高15~20 cm，地径0.30 cm以上规格的苗木栽植，栽植密度为0.3 m×0.3 m，遮阳透光率在50%左右。

For the mountainous sites, land under the crown of broadleaf at grade Ⅰ or Ⅱ stands, as well as eastward shady land would be preferential, and super seedlings of grade I or II with 21-25 cm for height and 0.40 cm for diameter should be selected for cultivation.

若利用山地经营，可选择在Ⅰ、Ⅱ类立地的残次阔叶林林冠下或地形隐蔽、东向的山垅旱地，采用苗高21~25 cm，地径0.40 cm以上的Ⅰ、Ⅱ级优质苗造林，残次阔叶树要求林冠透光率在55%左右。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。