Gap Dynamics and Tree Species Diversity in a Tropical Montane Rain Forest of Hainan Island,China

Based on investigation of 53 gaps and 25 quadrats (15m×15m each) of non-gap closed stand in an old-growth tropical montane rain forest of Hainan Island, China, canopy disturbance regimes and gap regeneration were studied. Gaps were elliptical in horizontal form, the ratio of long axis /short axis was about 1.4. Percentage of expanded gaps (EG) and canopy gaps (CG) area in the landscape were 53.5% and 25.2% respectively. EG ranged from 31.4 m2 to 488.2m2 and CG/rom 14.9m2 to 354.2m2, their average sizes were about 160 m2 and 80m2 respectively. Natural disturbance frequency for canopy gaps     

区域农业与农村可持续发展研究探索--辛德惠院士泛生态学理论与实践述评

辛德惠院士学术思想和理论的发展大致分为3个方面,即以输入决定律为基础的土地生产力主导战略理论、以区域综合治理与开发为基础的农业-农村综合发展理论以及以生态学泛化为基础的泛生态学理论.其中,泛生态学集中代表了他的理论大成.     

浸种处理对圆叶决明种子萌发的影响

摘要：为寻求圆叶决明(Chamaecrista rotundifolia)种子硬实破除技术,开展热水和硫酸浸种处理对2个圆叶决明品种种子萌发的影响试验。结果表明,未浸种条件下闽引圆叶决明、闽引2号圆叶决明种子硬实率分别达56.3%、76.0%。初始温度为100 ℃热水浸种3 min,闽引圆叶决明种子硬实率降至11.7%,发芽率升至42.7%,发芽指数达32.1,高于其他热水浸种处理。不同热水浸种处理闽引2号圆叶决明的种子硬实率无显著差异。98%硫酸浸种10 min,闽引圆叶决明、闽引2号圆叶决明的种子硬实率分别降至1.3%、0,而且发芽指数均达峰值,分别为58.9、37.0,相应的发芽率分别为64.7%、80.0%。     

开垦和弃耕对黑河上游亚高山草甸土壤氮库的影响

通过分析天然放牧草地、20年燕麦耕地、3年燕麦弃耕地、10年燕麦弃耕地的七壤全氮、微生物量氮含量的差异,旨在探讨改变上地利用方式对黑河上游亚高山草甸土壤氮库的影响.结果表明:开垦和弃耕对黑河上游地区草地土壤氮库有显著影响.亚高山草甸被开垦为燕麦耕地20年后,土壤全氮含量(0-30cm)减少了21-35%,微生物量氮含量...     

Regional partitioning of agricultural non-point source pollution in China using a projection pursuit cluster model

A projection pursuit cluster(PPC) model was used to analyze the regional partitioning of agricultural non-point source pollution in China.The environmental factors impacting the agricultural non-point source pollution were compiled into a projection index to set up the projection index function.A novel optimization algorithm called Free search(FS) was introduced to optimize the projection direction of the PPC model.By making the appropriate improvements as we explored the use of the algorithm,it became simpler,and developed better exploration abilities.Thus,the multi-factor problem was converted into a single-factor cluster,according to the projection,which successfully avoided subjective disturbance and produced objective results.The cluster results of the PPC model mirror the actual regional partitioning of the agricultural non-point source pollution in China,indicating that the PPC model is a powerful tool in multi-factor cluster analysis,and could be a new method for the regional partitioning of agricultural non-point source pollution.     

寡聚糖对大豆防御酶活性的影响

采用寡聚糖处理大豆叶片,并在诱导后接种大豆花叶病毒(SMV),用比色法测定3种防御酶活性。结果表明,寡聚糖2号、6号和7号诱导后或诱导后接种大豆花叶病毒(SMV),均使大豆叶片过氧化物酶(POD)和多酚氧化酶(PPO)活性提高,其中寡聚糖7号提高幅度大于2号和6号。     

Polypores on Spruce in Northeast China

Poroid species of wood-inhabiting fungi growing on spruce (Picea koraiensis Nakai or Picea yezoensis (Sieb. & Zucc.) Carriere) in Northeast China were investigated during 1993-2002, and 71 species were recorded from these trees or their wood. Skeletocutis lilacina A. David & Jean Keller and Skeletocutis papyracea A. David are new to China. Fomitopsis pinicola (Sw.:Fr.) P. Karst., Onnia leporina (Fr.) H. Jahn, Perenniporia subacida (Peck) Donk, Phaeolus sckweinitzii (Fr.:Fr.) Pat., Phellinidium sulphurascens (Pilat) Y.C. Dai and Phellinus yamanoi (Imazeki) Parmasto are the pathogens on the two trees. Among the 71 species 18 species (ca. 25% of all species) are considered as rare species, 34 species (48% of all species) are the occasional species, and 19 species (27% of all species) are the common species.     

FORESTAR:东北地区多目标森林经营的决策支持系统(英文)

我国林业过去曾经实行过大砍大造的方针,导致全国范围的生态灾难和林区的经济困境。当前正在实施的天然林保护工程和退耕焕还林工程是在我国山地森林应用生态系统管理的良好时机。针对长白山地区天然林的保护与经营,我们建立了一个决策支持系统,简称为FORESTAR。它是以林业局为单位、用GIS框架下的森林资源清查数据建立的。最初的版本包括两个子模块:森林采伐设计和森林恢复经营。在每个子模块下,用户可以比较各种决策条件下的效果,以便从中选优。这个决策支持系统可以用来帮助各级林业工作者实现上下一致的、多目标的森林经营管理规划。图2参17。     

Review of Researches in Terrestrial Ecosystem Services——Theories and Methods

The paper has expounded the intension of ecosystem services, which indicated the effectiveness and environmental condition of survival formed and maintained during the ecosystem process. It has maintained mankind with life supporting system of survival, biology geochemistry circulation and hydrographic circulation, purify environment, balance and stability of atmospheric chemistry. This paper reviews and introduces the development and research of domestic and ecosystem services, as well as the appraising indexes and the methods of economic values assessment. At the same time, the author also put forward the opinion of himself.