山东蓬莱沿海岩相潮间带贝类的垂直分布

蓬莱 ( 37°2 5’N～ 37°4 9’56”N ,1 2 0°34’4 4”E～ 1 2 1°0 9’E)位于山东半岛的北端 ,黄渤海交界处。作者通过对蓬莱沿海潮间带生物的调查 ,初步分析了岩相潮间带贝类种类及其垂直分布特点 ,依潮间带的不同区域而呈带状分布 (高潮带为滨螺群落 ,中潮带为牡蛎群落 ,低潮带为贻贝 -锈凹螺群落 )并简单分析了主要经济贝类的分布状况 ,为潮间带贝类资源合理开发与保护提供了基础资料 ,供海洋生态学、环保、水产部门参考     

Assessment Methods for Sea-RelatedHazards in Coastal Areas

Italian legislation provides for hazardcontingency plans to be prepared by the regional,provincial and local authorities. Despite the extentof damage often caused on the Italian coasts by theaction of the sea, sea related hazards have so farbeen usually ignored; only recently a limited budgetin some provinces was allocated for the analysis ofrisks related to storm damage.The present paper reports on the proceduresand the techniques employed and tested within theframework of the provincial contingency plan onthe coast of the Salerno province in Italy (Figure 1).The work was mainly oriented to the evaluation ofthe potential damage that can be caused by the directaction of waves on coastal areas and on thepreparation of hazard maps. The methods and the datathat can be used to evaluate the risks are reviewed here,first by rapid examination of the wave fieldformation offshore and its transformation on shallowwater and then by considering the run-up on beachesand infrastructures; the paper is focussed inparticular on these latter problems, which – formsome point of view – are original and specific tocivil protection problems.     

喀斯特山区不同石漠化等级下土壤养分贮量与价值评估——以乌箐、偏岩等岩溶小流域为例

为探讨石漠化等级对土壤养分贮量与经济价值的影响,以贵州省金沙县喀斯特山区无石漠化农耕地(Ⅰ)为对照,在研究潜在(Ⅱ)、轻度(Ⅲ)、中度(Ⅳ)、重度(Ⅴ)石漠化土壤养分含量变化的基础上,采用土壤养分库贮量计算方法和价值替代法计算评估了不同石漠化等级下土壤养分贮量及其潜在价值。结果表明:(1)0~40cm土层有机质、全氮、水解氮、全磷、有效磷、全钾、速效钾含量分别为32.31~104.12g/kg、1.35~2.87g/kg、76.90~124.00mg/kg、0.49~1.12g/kg、1.03~10.71mg/kg,12.25~26.22g/kg、114.35~245.35mg/kg;(2)土壤养分总贮量和有机质、全氮、全磷、全钾贮量依次为3.79~61.41t/hm2和2.55~48.56t/hm2、0.13~1.36t/hm2、0.04~0.52t/hm2、1.07~10.97t/hm2;(3)土壤养分总价值和有机质、全氮、全磷、全钾价值分别为0.86~9.80万元/hm2和0.08~1.55万元/hm2、0.29~3.08万元/hm2、0.04~0.53万元/hm2、0.45~4.64万元/hm2;(4)土壤养分贮量、价值均以Ⅰ最高,Ⅴ最低,随着石漠化程度加剧,土壤养分含量、贮量和价值均下降。      

Transfer of results from reed research into practice as illustrated by reed protection measures in Berlin

There is great interest in solving the question of how far the successful establishment of common reed for shore restoration is influenced by genetically determined characteristics of different reed clones. For this purpose, ten reed clones were planted at six artificial sand banks in 1995, according to a special planting design. The growth and expansion performance of the clones was compared.The reed plants grew without significant stress in the first vegetation period, resulting in newly established reed stands in a very good condition at the end of the season. Despite the same site conditions at the experimental plots, the planted clones differed significantly in their morphology and stand structure. By comparison, reed plants of the same clone exhibited strong similarity on all experimental plots. These results appear to justify the assertion that, at least during the initial phase of establishing a reed stand, the development of stand structure is determined more by genetically controlled programmes than by site conditions. Only long-term investigations will be able to clarify to what extent stable stand structures are formed by genetically controlled programmes after polycormons reach maturity.     

水化学和钙华碳氧稳定同位素在古环境重建中的应用——以贵州荔波小七孔景区响水河为例

文章报道了响水河河水的现场监测结果,得到响水河河水的Ca2+和HCO-3非常低,这明显与河床中大规模钙华的存在和景区内发育的茂密植被不匹配;并仔细观察发现,钙华表面有被侵蚀的痕迹,如溶蚀槽和溶蚀坑等,这说明目前所见钙华可能是过去环境条件下的产物。根据钙华碳氧稳定同位素组成特征的分析得出:近4000年来,该地区总的气候环境变化趋势是4000～3400aB.P.为相对温暖湿润期,植被生长好,为良性生态期;3400～2000aB.P.前期仍比较温暖但干燥,后期到2000aB.P.左右变得比较凉爽,从这一冷期到大致900aB.P.前后,气候有些波动,但幅度较小,夹有冷暖干湿的交替;而900aB.P.至今,钙华碳氧稳定同位素值的急剧增加,反映出气候的冷干和源区人类活动加剧造成的水土流失增加,岩溶石漠化加重,生态朝恶化方向发展     

基于RBFN模型的贵州省石漠化危险度评价

西南喀斯特山区石漠化已成为当地发展的重大障碍,国内诸多学者对此做了大量研究工作。本文在前人研究成果的基础上,选取影响喀斯特石漠化演化的相关指标,运用GIS技术提取各指标数据,建立RBFN模型 (Radial Basis Function Network,径向基函数网络模型),根据不同石漠化危险程度标准,选取12个市县相关数据进行训练,确定网络模型参数,进而对贵州省82个市、县 (自治州) 的喀斯特石漠化危险度进行了评价,结果显示：贵州省西南部的西南-东北沿线为喀斯特石漠化发生的极强危险区、整个西南部为强危险区,北部地区为中度危险区,而东南部地区为轻度危险区,并利用他人研究成果进行了对比验证,发现结果较为理想。     

Absorption Efficiencies of the Intertidal Mangrove Dwelling Mollusk Melampus coffeus LINNÉ and the Rocky Intertidal Mollusk Acanthopleura granulata GMELIN

Abstract. .The absorption efficiencies of the intertidal mangrove dwelling mollusk Melampus coffeus and the rocky intertidal dwelling mollusk Acanthopleura granulata were calculated by a modification of CONOVER'S (1966) equation. M. coffeus tended to consume fresh mangrove leaves indicating that M. coffeus may obtain much of its energy from the actual substrate material rather than from associated bacteria and meiofauna on decaying leaves. Obtaining energy directly from the substrate may be a mechanism for M. coffeus to utilize its food source more efficiently. In contrast, chitons (A. granulata) may utilize the higher energy components of their limited intertidal microflora! food source. Using the high energy component of a food source may be an additional mechanism by which organisms efficiently utilize a food source.     

中国南方岩溶区土地石漠化的成因与过程

中国南方岩溶区是石漠化广为发展的脆弱生态区域。南方岩溶区土地石漠化的起因既有自然因素,也有人为因素。在地质历史时期其自身环境孕育和存在着自然石漠化过程,在历史时期—现代自然石漠化过程又叠加了人为石漠化过程,人为活动加速、加剧了石漠化的发展。清朝初、中期是人为活动影响石漠化的重要转折时期,此后人为因素作用比重逐渐超过自然因素的作用比重。岩溶区土地石漠化过程是由植被退化丧失过程、土壤侵蚀过程、地表水流失过程、基岩溶蚀侵蚀过程、土地生物生产力退化过程合成的地表生态过程,其实质是形成石质荒漠的土地退化过程。