国际旅游岛背景下海南休闲农业发展探讨

通过分析国际旅游岛的建设背景，认为海南大力发展热带休闲农业，可以打造海南生态休闲旅游的新品牌、构筑海南旅游发展的新亮点。并结合海南休闲农业发展的实际情况，就如何进一步发展海南休闲农业提出对策和建议。     

半解析数值法分析四边自由中厚板的受力特性

根据Reissner中厚板理论,结合胡海昌的解耦函数法,本文构造出一种能满足全部自由边界条件的试函数,并以此建立两个广义位移,用该位移求得双参数地基上四边自由矩形中厚板弯曲问题的解析解.利用最小平方误差法并结合数值算例,重点探讨了板弯剪刚度比、地基刚度以及地基剪切模量对弹性地基上四边自由中厚板受力特性影响规律.结果显示:(1)Vlazov地基模型优于Winkle地基模型,因为它考虑了地基剪切刚度的影响,使得板的内力和挠度均有减小,发挥了地基的潜力;(2)当地基刚度较小时,地基的剪切模量对板的挠度和内力的影响显著;当地基的刚度较大时,剪切模量对板的内力和挠度的影响不明显.本文计算精度高,计算工作量小且便于对参数进行分析,以及提供数值分析法判据等多项特点.     

老年农民工人力资源开发研究

开发老年农民工人力资源不仅是老年农民工自我发展的需要,也是社会发展的必须。老年农民工与青年农民工可以优势互补,发挥老年农民工的余热既可消化农村剩余劳动力,又可促进城市化进程。     

国内甜菜产区主要害虫种类及防治技术研究动态

综述了甜菜主要害虫种类及防治技术等方面的研究进展，并对甜菜主要害虫种类的防治策略做了进一步探讨。     

基于SWOT分析的腾冲县核桃产业发展对策研究

采用SWOT分析法,分析腾冲县核桃产业发展情况,优势为:土壤、气候适宜,产业发展基础好,旅游人流量大;劣势为:品种莨莠不齐,科技支撑水平低,资源投入不足,深加工水平低等;机会为:市场前景广阔,政策支持等;威胁为:市场竞争激烈,替代产品威胁。藉此从SO战略、WO战略、ST战略和WT战略4个方面提出核桃产业发展对策。     

我国经济林产品的发展现状及开发利用对策

综合介绍了我国经济林产品的发展现状及开发利用对策。我国一些经济林产品，如油茶、油桐、漆树、白蜡、板粟、等栽培历史悠久，产量居世界之冠；一些经济林产品的质量在世界上享有盛名，如桐油、核桃仁；近年来在一些经济林产品的开发利用上取得了一定的进展；如采用加温融合与加压压榨法提取橄榄油比常规压榨法提高出油量１４．０７％。     

我国森林蔬菜的开发利用现状与前景

对我国森林蔬菜开发利用的意义、现状和存在的问题进行了综述,并结合存在的问题提出了具有可行性的建议和对策,以期为森林蔬菜开发利用研究提供一些理论性的依据,使我国森林蔬菜产业早日走上规模化、国际化道路.     

Differential responses of Bolivian timber species to prescribed fire and other gap treatments

We followed the establishment and growth response of 13 commercial tree species to canopy opening, above-ground biomass removal, and experimental burns of low and high intensities in a lowland dry forest in Bolivia. Three patterns of response to treatments were observed among the most abundant commercial tree species. (1) Shade-intolerant species regenerated mostly from seed and had the highest survival and growth rates following high-intensity burns. (2) Shade-tolerant species were abundant in gap control and plant removal treatments. Treatments had little effect on the height growth of these species. (3) Individuals of root sprouting species were most abundant following plant removal and low-intensity burn treatments. Treatments had little effect on the height growth of these species. The wide variation in species responses to gap treatments found in this study not only reinforces the concept that species are distributed along a continuum of shade-tolerance levels, but that other aspects of species biology, such as seed dispersal type or sprouting behavior, further differentiate regeneration strategies. The variety of regeneration strategies found among the species at this forest site will require a flexible management scheme that mixes more intensive silvicultural treatments such as prescribed burning with less intensive treatments.     

河北省林木种苗发展现状、趋势与管理对策

总结了河北省林木种苗建设取得的成绩及存在的问题，根据林业和生态建设的新形势及河北省种苗发展现状，分析了林木种苗发展的趋势，提出了河北省林木种苗管理的总体思路和“坚持一个中心，抓好两件大事，建设三大体系，抓好四项工作”的管理对策。     

Tree-ring: a suitable implement for spatial and temporal fire distribution analysis in savanna woodland and dry forest

Based on 120 stem discs collected during3 months of fieldwork along a 12 km route,the history of fires in the Wari Maro Forest(09 1000 N–02 1000E) over the past century in savanna woodland and dry forest was reconstituted.Three major ecological areas are characterized:one highly burnt zone located between two relative less burnt areas.By analyzing tree rings,246 fire scars were identified.The scars were caused by 51 fire years,occurring at a mean interval of 2.23 years.From 1890 to1965,only 6 years with fires were recorded from sampled trees.Since 1966,no year has passed without fire.The fire frequency point scale reached 14 years.This was the case of Burkea africana,which has been identified as a species tolerant to fire and could be planted to create a natural firewall.In contrast,Anogeissus leiocarpa is highly sensitive to fire,and in a dry forest ecosystem that burns seasonally,it requires a special conservation plan.Two new concepts are described:the rebarking of trees after fire and Mean Kilometer Fire Interval.The first concept was tested with Daniellia oliveri(Rolfe) Hutch & Dalz trees,and the second concept was used to evaluate spatial fire distribution.We demonstrate that savanna woodland and dry forest were subject to a degradation process caused by destructive fires related to vegetation cover clearance and illegal logging.