基于GIS和USLE的鄱阳湖流域土壤侵蚀敏感性评价

水土流失是鄱阳湖流域严重的生态环境问题。以USLE模型为基础,结合鄱阳湖流域自然环境特征,确定评价指标及其分级标准。运用GIS技术,实现研究区土壤侵蚀敏感性综合评价,揭示其流域空间分异特征及规律,并对流域土壤侵蚀产生的原因进行分析,提出了调控措施。研究表明：流域土壤侵蚀敏感性主要以中度和高度敏感为主,不敏感、轻度和极度敏感所占比例较少。从空间分布上来看,极敏感地区集中分布在赣东南部的宁都县和会昌县,赣中吉安县和泰和县,赣西北的万载县,赣东北的德兴市和上饶市;高度敏感地区主要分布在赣江、抚河、信江、饶河及修水这5条河流域中、上游河流两岸和鄱阳湖滨湖地区,以及坡度<25°的坡耕地、疏幼林地;中度敏感性地区分布面积最广,在整个流域内各地貌和用地类型(除水域外)上均有分布;轻度敏感性地区主要分布在赣西南的井冈山市、万安县、赣县、大余县一带,呈月牙形分布;不敏感地区以鄱阳湖及五河沿线向四周呈辐射状分布,还包括赣西北的拓林水库、赣西江口水库和赣东洪门水库等区域。     

Stand carbon stocks and soil carbon and nitrogen storage for riparian and upland forests of boreal lakes in northeastern Ontario

The establishment of shoreline reserves (buffer strips) has guided riparian forest management in Ontario for many years. A riparian area is defined as the transitional zone between the aquatic and terrestrial environments and therefore is also known as the aquatic/terrestrial ecotone. While many functions of riparian forests have been recognized and well studied, less is known about their potential to sequester C and whether this potential differs from other areas in the boreal forest landscape. Increased harvesting pressure due to decreased wood supply in Ontario and debate about the effectiveness of the current reserve guidelines has resulted in a renewed interest in harvesting riparian forests. In this study riparian and upslope forest C and soil C and N storage were quantified for 21 lakes shorelines at the Esker Lakes Research Area, a boreal forest ecosystem in northeastern Ontario, Canada. Objectives were to compare the C and N storage potential of riparian forests with those of adjacent upland forests, and to examine the potential impacts of harvesting on C stocks in riparian zones of the boreal forest.Riparian forests did not differ from upslope stands in terms of total aboveground overstory C storage although there were significant differences in stocking density and species composition. However, a greater proportion of total site C in riparian areas was stored in the overstory tree layer (>5 cm dbh) compared to upslope areas. Forest floor layers were deeper and stored more C and N in riparian forest stands in comparison to upslope stands. In contrast, mineral soil in upslope stands had greater C and N storage than mineral soil horizons within the riparian forest. As a result, the riparian organic horizons comprise a larger percentage of the overall soil storage of C and N than upslope layers. Currently practiced full-tree harvesting would result in a removal of approximately 76% of total aboveground C (17% of the ecosystem C) in upslope stands compared to 98% of total aboveground C (35% of the ecosystem C) in riparian forests. Selective or modified harvesting in riparian zones could decrease C removal to levels equal to that obtained by full-tree harvesting in upslope areas.     

简述高等中医院校图书馆新印古医籍的管理与利用

各高等中医院校图书馆都有相当数量的新印古医籍的收藏。但长期以来却未引起图书馆工作人员及读者的重视。从其特点、收集与利用等诸方面阐述了相关问题,以期引起管理者及读者的重视。     

Hydrological response to land use and land cover changes in a sub-watershed of West Liaohe River Basin,China

In recent years, the streamflow of the Laohahe Basin in China showed a dramatic decrease during the rainy season as a result of climate change and/or human activities. The objective of this work was to document significant streamflow changes caused by land use and land cover （LULC） changes and to quantify the impacts of the observed changes in Laohahe Basin. in the study area, the observed streamflow has been influenced by LULC changes, dams, and irrigation from rivers, industry, livestock and human consumption. Most importantly, the growth of population and gross domestic product （GDP） accompanied by the growth in industrial and agricultural activities, which led to LULC changes with increased residential land and cropland and decreased grassland since 2000s. Statistical methods and Variable Infiltration Capacity （VIC） hydrological model were used to estimate the effects of climate change and LULC changes on streamflow and evaportranspiration lET）. First, the streamflow data of the study area were divided into three sub-periods according to the Pettitt test. The hydrological process was then simulated by VIC model from 1964 to 2009. Furthermore, we compared the simulated results based on land use scenarios in 1989, 1999 and 2007, respectively for exploring the effect of LULC changes on the spatio-temporal distribution of streamflow and ET in the Laohahe Basin. The results suggest that, accompanied with climate change, the LULC changes and human water consumption appeared to be the most likely factors contributing to the sig- nificant reduction in streamflow in the Laohahe Basin by 64% from1999 to 2009.     

Pro-inflammatory effect of glucocorticoids in brain

Glucocorticoids are necessary for stress response and universally used as anti-inflammatory agents. However, recent studies indicate that glucocorticoids not only enhance the pro-inflammatory effect of stress in the brain but also aggravate brain inflammation when glucocorticoid level is chronically elevated or abnormally increased. In addition, inflammatory response has detrimental effects on the repair of injury in the brain and contributes to several neuropsychiatric diseases. Accordingly, the capacity of glucocorticoids to augment inflammation in the brain deserves further investigation for effective clinical attenuation of brain inflammation. In this paper, we review recent advances in the characteristics and the possible mechanisms of the pro-inflammatory effect of glucocorticoids in the brain.     

Determination of ligustilide in rat brain after nasal administration of essential oil from Rhizoma Chuanxiong

A simple and sensitive HPLC–UV method was developed to determine ligustilide in rat brain samples after nasal administration. The lower limit of quantification (LLOQ) was 245 ng/ml for ligustilide. The calibration curve was linear over a concentration range of 245–4900 ng/ml. Brain samples were obtained at regular time intervals after nasal administration of ligustilide (45 mg/kg). Ligustilide could be detected in rat brain only after 5 min of nasal administration; which showed that ligustilide may have a rapid onset of action. This result illustrates that intranasal administration of ligustilide may act as a promising alternative to conventional routes of administration.     

面向对象GIS建模的原则与方法

首先阐述了面向对象GIS建模的概念,然后提出面向对象GIS建模的三原则:应用目的原则、应用深度原则和过程原则,最后结合校园道路设施GIS建模实例给出面向对象GIS建模的方法过程,并将面向对象GIS建模的结果概括为:一图、一表、一库,能够给读者的实际建模工作提供一些有益参考。     

景以境出情由境发——论江南古典园林匾额楹联的审美文化内涵

江南古典园林以意境取胜，注重塑造韵味。保存至今的，同时也是艺术价值最高的多为文人园林，其建造设计者多为一些艺术素养很高的文人画家，浸透了精致的文人主体情致，具有耐人寻味的“意境美”。其中的匾额楹联的设置更是这一意匠和文心的独特体现。“景以境出，情由境发”，匾额楹联在意境创造中显示出很高的艺术价值和文化价值。     

基于工作过程导向的高职ASP.NET动态网站课程模式研究

根据高职教育的目标,提出了以工作任务驱动为教学形式的基于工作过程导向的高职ASP.NET动态网站课程模式,运用先进的教学理念,把理论知识、实践技能与实际应用环境结合在一起,构成学习情境,很好地实现了教学用合一。     

具有混合故障模型的区间系统的可靠控制

从生态学视角来研究企业竞争的动态演化已成为一个研究热点.针对现有研究文献中只讨论二维系统的不足，以三个企业之间的竞争为例，构造了企业间竞争的三维模型，运用微分方程稳定性理论分析其稳定性，并由此揭示出企业间竞争的动力学机制.数值仿真结果表明，该三维模型能有效地模拟企业间竞争的动态演化规律.