Effect of horizontal advection induced by intrusion of the Kuroshio water on plankton biomass in the spring fishing period of shirasu on the Pacific coast of Japan

ABSTRACT:   This study explored the fundamental process that controls interannual change in plankton biomass on the Pacific coast of Japan, focusing on the spring period of shirasu fishery. A 1-D model of primary production revealed that the strength of horizontal advection induced by warm water intrusion from the Kuroshio into the Pacific coast is the most critical for plankton biomass compared with other factors such as diffusion and production. This conclusion was also confirmed by a sensitivity analysis of the model.     

毛竹林理水固土功能评述

从毛竹林林冠对降雨的再分配功能、林下枯落物对水源的涵养功能和毛竹林地下鞭根系统固土功能等三方面对毛竹林的理水固土功能进行了简单地评述,并对该方向的研究重点提出一些自己的看法.     

A Gis-derived integrated moisture index to predict forest composition and productivity of Ohio forests (U.S.A.)

A geographic information system (GIS) approach was used in conjunction with forest-plot data to develop an integrated moisture index (IMI), which was then used to predict forest productivity (site index) and species composition for forests in Ohio. In this region, typical of eastern hardwoods across the Midwest and southern Appalachians, topographic aspect and position (rather than elevation) change drastically at the fine scale and strongly influence many ecological functions. Elevational contours, soil series mapping units, and plot locations were digitized for the Vinton Furnace Experimental Forest in southeastern Ohio and gridded to 7.5-m cells for GIS modeling. Several landscape features (a slope-aspect shading index, cumulative flow of water downslope, curvature of the landscape, and water-holding capacity of the soil) were used to create the IMI, which was then statistically analyzed with site-index values and composition data for plots. On the basis of IMI values for forest land harvested in the past 30 years, we estimated oak site index and the percentage composition of two major species groups in the region: oak (Quercus spp.), and yellow poplar (Liriodendron tulipifera) plus black cherry (Prunus serotina). The derived statistical relationships were then applied in the GIS to create maps of site index and composition, and verified with independent data. The maps show the oaks will dominate on dry, ridge top positions (i.e., low site index), while the yellow poplar and black cherry will predominate on mesic sites. Digital elevation models with coarser resolution (1:24K, 1:100K, 1:250K) also were tested in the same manner. We had generally good success for 1:24K, moderate success for 1:100K, but no success for 1:250K data. This simple and portable approach has the advantage of using readily available GIS information which is time-invariant and requires no fieldwork. The IMI can be used to better manage forest resources where moisture is limiting and to predict how the resource will change under various forms of ecosystem management.     

湖南省森林公益效能的经济评价Ⅰ森林的木材生产效益与水源涵养效益

根据多年定位测定的数据以及<湖南省森林资源主要数据汇编>、<湖南省农业区划(8)>和湖南省水利厅有关资料,对湖南省森林的木材生产效益和水源涵养效益进行计量评估,结果表明,湖南省现有的森林每年生长木材488.7675万m3,年平均生产木材效益24.44亿圆,而其森林的水源涵养效益中,森林贮水功能效益9.84亿圆,防洪效益3.68亿圆,枯水期增加的水资源利用效益26.73亿圆.其涵养水源总效益共计40.25亿圆,是木材效益的1.65倍,同时,即使是灌草坡地调节水分的能力也明显高于裸地,因此.从水文学观点出发,对于难以造林的山坡、山顶,要注意灌木林的保护和经营,使其发挥更好的防水功能.     

几种鸡胚原代细胞的制备方法

在病毒分离、繁殖，中和试验及药物毒理试验中，细胞培养是经常被选用的技术。本文描述通过选择不同日龄的鸡胚，分别对皮肤上皮细胞、肝细胞和肾细胞进行了组织培养，确定了生长所需的培养液要求。认为１２日龄鸡胚适于皮肤上皮细胞的制备，１７～２０日龄鸡胚适合于肝细胞、肾细胞的制备，并确定了细胞生长的ｐＨ条件。     

从森林绿色核算看我国林业政策的优化

为了更好地为林业管理决策服务和为政策制定提供依据,该文在对国内外绿色核算研究综述的基础上,论述了绿色核算的概念,探讨了森林绿色核算的政策应用. 文章通过对我国2000、2004年的森林绿色核算研究结果的认真分析指出:2000—2004年,我国森林eaGDP(经环境调整的GDP)增加了0.11%,反映出林业对国民经济的贡献是不断增加的; 在我国森林环境服务、社会效益中,土壤保育、森林防护效益最大,固碳供养、水源涵养效益次之,森林游憩效益最小. 因此,在森林间接效益利用中,受益最大的是农业、水利、电力等部门,受益最小的是林业部门本身. 该文还对我国的森林绿色核算结果进行了政策优化分析,提出了加强政府对森林资源保护的直接管制和补偿,提供资助,加强森林资源保护的地方标准、法律的制定,促进林业人力资本的发展,明确产权等建议,以促进实现社会经济发展与森林资源增长的目标.      

Chromosomal location of fertility restoring genes for ‘wild abortive’ cytoplasmic male sterility using primary trisomics in rice

Summary Identification and location of fertility restoring genes facilitates their deployment in a hybrid breeding program involving cytoplasmic male sterility (CMS) system. The study aimed to locate fertility restorer genes of CMSWA system on specific chromosomes of rice using primary trisomics of IR36 (restorer), CMS (IR58025A) and maintainer (IR58025B) lines. Primary trisomic series (Triplo 1 to 12) was crossed as maternal parent with the maintainer line IR58025B. The selected trisomic and disomic F₁ plants were testcrossed as male parents with the CMS line IR58025A. Plants in testcross families derived from disomic F₁ plants (Group I crosses) were all diploid; however, in the testcross families derived from trisomic F₁ plants (Group II crosses), some trisomic plants were observed. Diploid plants in all testcross families were analyzed for pollen fertility using 1% IKI stain. All testeross families from Group I crosses segregated in the ratio of 2 fertile: 1 partially fertile+partially sterile: 1 sterile plants indicating that fertility restoration was controlled by two independent dominant genes: one of the genes was stronger than the other. Testcross families from Group II crosses segregated in 2 fertile: 1 partially fertile+ partially sterile: 1 sterile plants in crosses involving Triplo 1, 4, 5, 6, 8, 9, 11 and 12, but families involving triplo 7 and triplo 10 showed significantly higher X² values, indicating that the two fertility restorer genes were located on chromosome 7 and 10. Stronger restorer gene (Rf-WA-1) was located on chromosome 7 and weaker restorer gene (Rf-WA-2) was located on chromosome 10. These findings should facilitate tagging of these genes with molecular markers with the ultimate aim to practice marker-aided selection for fertility restoration ability.     

云南省金沙江流域退耕还林问题研究

云南省金沙江流域水土流失很严重 ,是全国生态环境建设的重点区域。坡耕地是该流域水土流失最为严重的地类 ,对不宜耕坡耕地实施退耕还林 (草 )工程具有重大战略意义。分析了该流域目前退耕还林(草 )工程中存在的主要问题 ,并就科学实施退耕还林 (草 )工程提出了具体的建议     

河北省森林景观空间格局分析

根据河北省森林景观现状,运用景观多样性指数、分维数、景观破碎化指数等计算方法,分析河北省森林资源空间分布特征和存在问题,指出河北省森林景观保护和发展方向。     

Effect of acidic deposition on hybrid poplar- primary or predisposing stress?

Our research examined the role of acidic deposition as a primary, or predisposing, stress on 8–12 week old cuttings of hybrid poplar (Populos deltoides x nigra). Firstly, we examined the role of acidic deposition as a primary stress in terms of physiological indicators (gas exchange, chlorophyll concentrations, chlorophyll-a fluorescence). Our results suggest that levels of acid precipitation of > pH 3.5 did not act as a primary stress. Secondly, we hypothesized that acidic deposition could act by making trees more susceptible to drought. An acid treatment exposure regime was followed by 3–4 days of drought stress in a controlled environment. Preexposure to acidic deposition did not increase the degree, or rate of appearance, of water stress as indicated by predawn xylem pressure potentials and leaf conductances. Examination of cuticular water loss from excised leaves suggested that this parameter was insensitive to acidic deposition from pH 3.0 to 5.5.