对烧材消耗量调查方法的初步研究

对目前我国森林资源消耗量及消耗结构调查方法中存在的一些问题进行了分析,并就烧材消耗量调查提出了一套新的调查方法,同时利用以往的调查材料对新的调查方法进行了例证。     

TM卫星影像图在剑河县森林资源二类调查中的应用

贵州省 1999年第一次利用TM卫星影像图对剑河县进行森林资源二类调查。详细介绍了调查方法、步骤 ,并进行了判读精度分析 ,对存在的问题 ,提出了改进意见     

森林资源规划设计调查发展及区划标志的设置

文章对我国森林规划设计调查工作的发展做了简要回顾,对森林规划设计调查技术的发展趋势进行了阐述,并结合新技术、新仪器在森林规划设计调查中的广泛应用,对各种区划标志的建立提出了自己的见解。     

浙江省遂昌县毛竹雨雪冰冻灾害调查

简述了遂昌县毛竹雨雪冰冻害灾害损失调查的调查方法、结果,对影响灾害程度的主要因子进行了分析,并提出了今后生产建议。     

克什克腾旗林业有害生物调查分析

文章根据2014年赤峰市克什克腾旗森林资源规划设计调查中专项调查提供的基础调查数据,对克什克腾旗林业有害生物的发生特点和原因进行综合分析,并对克什克腾旗发生林业有害生物防治,提出了相应的建议。     

云南临沧机场鸟类潜在威胁调查及防范措施

2005年9～10月采用样带调查法,并结合社会访问调查,对临沧机场及其周边的鸟类进行实地调查。调查到鸟类124种,其中普通鵟等26种为对航空飞行有潜在威胁的鸟类,并提出了相应的防范措施。     

加格达奇林业局榛子的分布及保护利用价值

文章对大兴安岭加格达奇林业局的榛子进行了调查、评价,并提出保护利用价值。     

人工红松林的初步研究

对松花江林区浓河林场的人工红松林进行了调查研究,并提出3点建议     

云南临沧机场鸟类潜在威胁调查及防范措施

2005年9～10月采用样带调查法,并结合社会访问调查,对临沧机场及其周边的鸟类进行实地调查.调查到鸟类124种,其中普通(狂鸟)等26种为对航空飞行有潜在威胁的鸟类,并提出了相应的防范措施.     

吉林省樟子松人工林大面积枯黄现象的调查

1996年5月至8月，对我省长春、吉林等地樟子松人工林大面积枯黄现象进行了调查，并对调查中所见到的病虫种类及危害进行了分析，据此提出防治建议。     

浙江上虞杨树病虫害种类调查

采用普查和重点调查相结合的方法,对浙江省上虞市海涂杨树防护林病虫害种类和为害程度进行了较为系统的调查,收录杨树虫害41种,分别隶属4目21科,病害8种。收集浸渍幼虫标本30余件,针插标本近300件,其中包括了杨树的主要害虫。并且对绝大部分标本在收集的第一现场进行了摄影记录。     

柿树主要病虫害综合治理

在河南焦作地区柿树主要病虫害有8种，以柿蒂虫、日本龟蜡蚧危害严重。蛀果率在30％以下时，采取人工防治；当蛀果率达30％以上时，采取综合防治，平均防治率达90％左右。     

Influence of explant source on in vitro axillary shoot formation in oak seedlings

In vitro shoot development was slower for apical shoot explants of young oak (Quercus robur L.) seedlings growing on Woody Plant Medium containing activated charcoal than for nodal shoot explants. The rate of in vitro shoot development was slowest in explants taken from seedlings that were undergoing rapid shoot elongation and most rapid in explants taken from seedlings that had stopped elongating and had fully expanded leaves. Maximum rooting was achieved on half-strength Woody Plant Medium containing activated charcoal. Rooting ability was not influenced by explant source.     

云南河口地区2007/2008年冬春低温与热带作物寒害

通过对2007/2008年冬春河口地区热带作物受寒害调研,总结了河口地区低温寒害时空分布规律,提出了主要热带作物寒害的防御对策。     

Effect of settings of digital fisheye photography to estimate relative illuminance within forest under low light conditions

In order to evaluate the effects of settings of digital fisheye photography on estimates of relative illuminance (RI) within a forest under low light conditions, we assessed the effectiveness of some estimators, i.e., canopy openness (CO), sky factor (SF), and diffuse transmittance (DIF). The estimates were calculated from digital hemispherical photographs taken with two different exposure settings, i.e., the reference exposure setting and the auto-exposure setting. We also presented a new estimator (%Exposure), which does not require image analysis, and compared it with other estimators calculated from a digital hemispherical photograph using image analysis. The CO, SF, and DIF calculated from digital hemispherical photographs taken with auto-exposure setting were not significantly correlated with RI. However, those calculated from digital hemispherical photographs taken with reference exposure settings were significantly correlated with RI. On the other hand, %Exposure showed a slightly higher correlation with RI compared with the other estimators.     

Terrestrial plants require nutrients in similar proportions

Theoretical considerations based on nutrition experiments suggest that nutrient ratios of terrestrial plants are similar to the Redfield ratio found in marine phytoplankton. Laboratory experiments have shown that seedlings of many different plant species have similar nutrient concentration ratios when supplied with nutrients at free access. However, at free access, nutrients are likely to be taken up in amounts in excess of a plant's requirements for growth. In further experiments, therefore, the supply rate of each nutrient was reduced so that excessive uptake did not occur. Again, similar nutrient ratios were found among the plant species tested, although the ratios differed from those found in plants given free access to nutrients. Based on the law of the minimum, we suggest that optimum nutrient ratios be defined as the ratios found in plants when all nutrients are limiting growth simultaneously. The literature on nutrient concentrations was surveyed to investigate nutrient ratios in terrestrial ecosystems. Nutrients taken into consideration were nitrogen, phosphorus, potassium, calcium and magnesium. Based on the assumption that nitrogen is either the limiting nutrient or, when not limiting, is taken up only in small excess amounts, we calculated nutrient ratios from published data. The calculated ratios corresponded closely to the ratios determined in laboratory and field experiments.     

雷竹开花期内源激素、氨基酸和营养成分含量变化

竹类植物开花较罕见 ,对其开花的原因也有不同的学说 ,如病理学说、营养学说、周期学说、个体变异和突变学说、气候学说等 (毛高喜等 ,1996 ;周芳纯 ,1998) ,但有学者认为内源激素对植物的开花有一定的调节作用 (王锋 ,1990 ;梁武元等 ,1986 ;王白坡等 ,1999;马国华等 ,1995 ;王彦清等 ,1998;陆军等 ,1993)。根据植物生长习性 ,开花植物有 2种不同衰老方式。其中一类是一生中只开一次花 ,即在开花结实后整株植株就衰老死亡 ,这类植物称为单稔植物 ,竹类植物就属于这一类植物。植物内源激素是体内十分重要的活性物质 ,它参与并调整植物的新陈…     

利用叶间温度解释葡萄园凝露状况

依据流体内平板热平衡理论，对葡萄园内的叶温、湿度、辐射、气温和风等环境气象因子进行小气侯观测，并取得了葡萄园凝露时间的解释模拟经验公式和参数，为葡萄园的病虫害预报、防治决策提供了科学依据。     

罗望子胶结构、性能、生产及其在食品工业中的应用

介绍了罗望子胶的结构、性能、生产及其在食品工业中用作增黏稳定剂、冰晶稳定剂、胶凝剂、品质改良剂等;并论述了罗望子胶在国内外的发展现状。     

歙县山核桃产业现状与发展对策

本文在多年实地调查和资料收集的基础上,对歙县山核桃的资源分布、生产管理等现状进行了调查,分析了山核桃生产中存在的主要问题,提出了产业发展应采取的措施和对策,为歙县山核桃产业健康发展提供借鉴。