干热河谷和干性森林水分特征的对比分析     

何亚平  费世民  蒋俊明  陈秀明 《四川林业科技》2007,28(4):4-9

本文研究了川西南山地安宁河流域干热河谷和干性森林的水分收支状况。结果表明:(1)干热河谷和干性森林的年降水量分别为1 067.95 mm和1 371.73 mm,年降水量的90%以上集中在6月～10月的雨季和夏秋季节;(2)干热河谷和干性森林年蒸发量为1 280 mm和1 089.75 mm,春夏蒸发占年蒸发量的65%和66%,旱季蒸发占年蒸发量的58%和61%,4月～6月是蒸发旺季,其次是7月～8月;(3)干热河谷和干性森林年水分盈余量分别为43.6 mm和481.95 mm,均存在季节性水分匮缺期,7月～10月、夏秋季节和雨季均是水分盈余期,其余为水分匮缺期;(4)干热河谷和干性森林年干燥度分别为1.205和0.8,表明该地区分别为半湿润和湿润性气候,还存在明显的季节差异,7月～10月、雨季和夏秋季节气候湿润,其余时期为半湿润或干旱气候;(5)干性森林在年降水量和水分盈余量上高于干热河谷,在年可能蒸发量和干燥度上明显低于干热河谷,这种差异还体现在水分参数的月分配、四季分配、旱雨季分配上;(6)干热河谷湿润程度差于干性森林,干热河谷植被和干性森林对各自水分收支状况具有良好的适应性;(7)封山育林需要注意旱季防火,人工促进还需要考虑土壤水分平衡规律和适地适树,进行"适度"造林。  相似文献   

长江流域防护林林副产品综合开发利用途径综述     

潘攀慕长龙  牟菊英张正香 《贵州林业科技》2004,32(1):13-19,26

本文对长江流域防护林主要构建树种的生物学特性及资源分布、主要林副产品及其用途、开发利用现状等进行了综述，旨在说明长江流域防护林的柏木、马尾松、杜仲、银杏、喜树和香樟等树种的林副产品综合开发利用有着广阔的前景和深远的意义。  相似文献   

嘉馨园住宅小区绿化景观设计   总被引：1，自引：0，他引：1  

董建云  李志涛  张涛  段大娟  王艳军 《河北林果研究》2007,22(1):99-102

充分利用现有地形、地貌,将嘉馨园居住小区规划为“一轴、两环、八点”的布局形式。以植物造景为主,强调构筑居住环境绿色空间,以立足生态,体现自然,弘扬文化的现代园林造园理念,来营造宜人的人居环境。  相似文献   

Forest Fire Environment and Characteristics in Northeastern China     

ZHAO Fengjun SHU Lifu WANG Mingyu LIU Xiaodong 《中国林业科技(英文版)》2007,6(4):62-66

Forest fires occurrence is influenced by many factors, such as inter-annual weather variations and regional fuel distributions. Fires occurrence in different forest region has distinct spatial and temporal characteristics. The paper studied the natural forest fire environment in Northeastern China, as well as forest fires occurrence, burned area and fire seasons in Northeastern Forest Region. The result shows that more than 50% of annual burned area occurred in Northeast China Forest Region. Main fire seasons in the region are spring and autumn. Fires occurrence in spring is larger than that in autumn. There are few fires in summer. The authors＇ suggestions for fire management department are to emphasize the fuel management, improve the roads conditions, and enhance the fires control ability.  相似文献   

关于城市供热计量收费的探讨     

陈强 《林业科技情报》2003,35(4):45-46

本文从我国城市集中供热收费的现状出发,探讨了城市供热计量收费的合理性、可行性及必然趋势。  相似文献   

Tree size dependence of litter production, and above-ground net production in a young Hinoki (Chamaecyparis obtusa) stand     

Stephen Adu-Bredu  Taketo Yokota  Kazuharu Ogawa  Akio Hagihara 《Journal of Forest Research》1997,2(1):31-37

The study was carried out in a 9-year-old hinoki cypress (Chamaecyparis obtusa (Sieb. et Zucc.) Endl.), stand over a span of three years from July 1992 to June 1995, primarily to predict litter production from exteral tree dimensions by combining open-top clothtrap and clipping methods. Litter production was virtually concentrated in October and November. Stem cross-sectional area at the crown base was proved to be the reliable predictor of litter production, and that single regression model was evolved irrespective of year. The regression model had proportional constants of 2.696 × 10⁻² and 3.540 × 10⁻² kg cm⁻² year⁻¹ for leaf litter and total litter production, respectively. Utilizing the model, leaf litter production of the stand was assessed to be 5.04, 5.12, and 4.99, and total litter production to be 6.48, 6.58, and 6.40 Mg ha⁻¹ year⁻¹ for the first, second and third year, respectively. Biomass increment was 6.67, 7.80, and 7.70, tree mortality was 0.15, 0.13, and 0.41, and insect grazing was 0.09, 0.05, and 0.002 Mg ha⁻¹ year⁻¹ for the first, second and third year, respectively. Above-groud net production was therefore 13.39, 14.55, and 14.51, Mg ha⁻¹ year⁻¹, and biomass accumulation ratio (biomass/net production) was 1.86, 2.21, and 2.76 year for the first, second and third year, respectively. Considering data from earlier studies and the results of this study, biomass accumulation ratio,BAR (year), of hinoki stands was best related to above-ground biomass,y (Mg ha⁻¹), using the power function:BAR=0.112y ^0.936. Excluding seedling stands, leaf efficiency (above-ground net production per unit leaf mass) of hinoki stands was 0.91±0.02 (SE) Mg Mg⁻¹ year⁻¹, irrespective of stand biomass or age.  相似文献   

海涂哺鸡竹与角竹春笋产出,笋株重量变化的比较研究     

孙国  徐绍清 《浙江林业科技》1995,15(4):30-34

在海涂含盐土壤中，角竹造林后成园快，笋单产高于哺鸡竹；角竹笋期５月１４日～６月１０日，哺鸡竹为４月２９日～５月１０日，盛笋期在出笋中前期，延续约１０～１２ｄ；竹笋单株重量哺鸡竹明显大于角竹，笋株粗重期在出笋初期和中前期，比盛笋期约早３ｄ，延续时间同盛笋期。因此，宜扩大角竹造林面积，延长供笋期，多产市场淡季笋，以获得更佳的效益。  相似文献   

福州地区人工杉木林分蓄积量表的研究     

兰名驹  王光玉 《福建林业科技》1994,21(1):62-66

本文提出以林分构成因子——林分胸高总断面积及林分平均高，估计林分蓄积量的办法，选取９种方程求解参数，配合了最优林分蓄积量经验方程，制定出《福州地区人工杉木林分蓄积量表》，对完善我省林业数表的种类、形式和内容，进行了初步尝试。  相似文献   

黑龙江林区伐区二次集材合理选型分析     

曹均  陈乃跃 《林业科技》1994,19(5):42-45

这篇文章通过生产率和生产成本讨论了黑龙江林区二次集材选型问题。研究结果表明，Ｊ—５０集材拖拉机分别与Ｊ—８０和解放汽车匹配最适宜。Ｊ—８０接运最短距离为０．７３ｋｍ，最长接运距离为１２ｋｍ；解放汽车最适接运为８．４３ｋｍ，超过１２ｋｍ时用汽车直运最合理。  相似文献   

八个竹种海涂引种试验报告   总被引：1，自引：0，他引：1  

张自立  徐绍清 《竹子研究汇刊》1993,12(2):15-21

本文从土壤含盐量着手对八个竹种在引种成活率、新竹抽发数及其质量、角竹笋产量等方面进行了较系统的研究。结果表明,土壤盐分影响竹子的生长发育,此影响一般随含盐量的增加而增加;不同竹种对土壤盐分的适应能力不同;角竹笋能获得高产,单产达20800kg/ha。参照产地母竹和引种地新竹的生长情况,我们建议:海涂地区发展竹子时可选用角竹、桂竹和红竹。  相似文献