长江岸线资源利用功能区划方法研究——以南通市域长江岸线为例

长江岸线是宝贵的自然资源。依据其资源条件，按照一定的区划原则，确定分段岸线使用的适宜性，合理安排港口、工业、城市生活以及生态保护等各项功能，实现岸线水域和陆域利用的合理布局，对长江岸线资源可持续利用具有重要意义。长江岸线资源利用功能区划必须坚持可持续开发作用、深水深用与浅水浅用、集约布局与纵深发展结合、上下游及左右岸利用方式协调、开发规模和时序与城市和产业发展适应等五条基本原则，区划过程一般包括4个步骤，即划分评价单元、评价岸线资源条件、分析岸线利用现状及需求、分析岸线利用适宜性并完成功能分区。提出了基于遥感与GIS的岸线资源条件和利用现状评价思路，引入了构造联表的岸线开发适宜性分析方法，并且应用这些方法对南通市域长江岸线资源进行了功能区划分。     

Radial basis function networks with partially classified data

The problem of estimating a classification rule with partially classified observations, which often occurs in biological and ecological modelling, and which is of major interest in pattern recognition, is discussed. Radial basis function networks for classification problems are presented and compared with the discriminant analysis with partially classified data, in situations where some observations in the training set are unclassified. An application on a set of morphometric data obtained from the skulls of 288 specimens of Microtus subterraneus and Microtus multiplex is performed. This example illustrates how the use of both classified and unclassified observations in the estimate of the hidden layer parameters has the potential to greatly improve the network performances.     

高频双区组合技术在电除尘器改造上的应用

介绍了广东某电厂一期1×300MW机组电除尘器因受场地限制,采用"高频双区组合技术"进行改造,改造后的除尘效率由99%(设计)提高到99.9%以上,为国内同类设备的提效改造提供了成功经验。     

旅游公共服务市场化与政府的作用研究

旅游公共服务是我国公共服务建设的基本领域,也是一个需要逐步完善的系统。旅游公共服务市场化,是顺应旅游行政改革和建设服务型政府的内在要求。结合旅游公共服务的实践,在分析旅游公共服务市场化的内涵、可行性以及旅游公共服务市场化条件和效率的基础上,提出旅游公共服务市场化的途径选择,最后探讨了政府在旅游公共服务市场化过程中应发挥的作用。     

Plague bacterium as a transformer species in prairie dogs and the grasslands of western North America

Invasive transformer species change the character, condition, form, or nature of ecosystems and deserve considerable attention from conservation scientists. We applied the transformer species concept to the plague bacterium Yersinia pestis in western North America, where the pathogen was introduced around 1900. Y. pestis transforms grassland ecosystems by severely depleting the abundance of prairie dogs (Cynomys spp.) and thereby causing declines in native species abundance and diversity, including threatened and endangered species; altering food web connections; altering the import and export of nutrients; causing a loss of ecosystem resilience to encroaching invasive plants; and modifying prairie dog burrows. Y. pestis poses an important challenge to conservation biologists because it causes trophic‐level perturbations that affect the stability of ecosystems. Unfortunately, understanding of the effects of Y. pestis on ecosystems is rudimentary, highlighting an acute need for continued research.     

底板突水煤层的突变学特征

对建立在力学分析基础上的突水条件进行适当变换，得到煤层底板突水势函数，它符合尖点突变模型。进一步分析，发现煤层底板突水具有突变、缓慢两条路径，并在突水临界点附近具有发散性和４ 模态软化等性质。根据这些特性，可通过调控煤层底板突水条件使之不突水，从而达到煤层底板突水治理并防患于未然的目的。     

An animal movement model incorporating home range and habitat selection

Wildlife biologists are often interested in how an animal uses space and the habitat resources within that space. We propose a single model that estimates an animal’s home range and habitat selection parameters within that range while accounting for the inherent autocorrelation in frequently sampled telemetry data. The model is applied to brown bear telemetry data in southeast Alaska. This article is based on a portion of this author’s Ph.D. dissertation completed in 2003 at the University of Iowa.     

Dynamic growth model for Scots pine (Pinus sylvestris L.) plantations in Galicia (north-western Spain)

In this study we developed a dynamic growth model for Scots pine (Pinus sylvestris L.) plantations in Galicia (north-western Spain). The data used to develop the model were obtained from a network of permanent plots, of between 10 and 55-year-old, which the Unidade de Xestión Forestal Sostible (Sustainable Forest Management Unit) of the University of Santiago de Compostela has set up in pure plantations of this species of pine in its area of distribution in Galicia. In this model, the initial stand conditions at any point in time are defined by three state variables (number of trees per hectare, stand basal area and dominant height), and are used to estimate stand volume, classified by commercial classes, for a given projection age. The model uses three transition functions expressed as algebraic difference equations of the three corresponding state variables used to project the stand state at any point in time. In addition, the model incorporates a function for predicting initial stand basal area, which can be used to establish the starting point for the simulation. This alternative should only be used when the stand is not yet established or when no inventory data are available. Once the state variables are known for a specific moment, a distribution function is used to estimate the number of trees in each diameter class, by recovering the parameters of the Weibull function, using the moments of first and second order of the distribution (arithmetic mean diameter and variance, respectively). By using a generalized height–diameter function to estimate the height of the average tree in each diameter class, combined with a taper function that uses the above predicted diameter and height, it is then possible to estimate total or merchantable stand volume.     

Estuarine management strategies and the predictability of ecosystem changes

The Dutch Delta Region (S-W Netherlands) originally consisted of interconnected estuaries, interfacing the rivers Rhine, Meuse and Schelde with the North Sea. The ecosystems were immature, with physical rather than biological control of population dynamics. Main functions were shipping and shellfisheries. An emergent function of the interconnected estuaries was the buffering and upgrading of river-borne substances before they entered the sea. Execution of the Delta Project in the period 1960–1986 resulted in isolation of several water systems disconnected from rivers and sea, and loss of gradients within these systems. Population dynamics were now controlled by chemical and biological rather than physical factors. Vulnerability to external perturbation increased. These changes also affected the buffering capacity, i.e. reduced the utility of the area as stabiliser of the geosystem. Recreational use and appreciation of natural values increased, potentially conflicting with shipping and shellfisheries. Retrospective analysis of the environmental policy and management revealed three consecutive strategies in the Delta Project. 1. Reactive one-issue management, focusing on safety against flooding only. This strategy aimed at complete closure of the estuaries thus transforming them into fresh water lakes. It has destroyed feed-backs and buffering between coastal and inland waters. This strategy has not promoted sustainable development and has increased the vulnerability of the area to future catastrophes. 2. Protective bio-ecological management focused on the preservation of existing values of landscape and environment, and resulted in the maintenance of saline conditions and preservation of marshes by shore protection measures. The drawback of this passive orientation to existing values ?where they are now? is the necessity of continuous intensive care because the natural adaptive ability is not being restored. 3. Constructive geo-ecological management is based on understanding functional properties within and between ecosystems as integrated elements of the landscape structure. This strategy aims at environmental protection, restoration and development of values ?where they must be?. Re-establishment of gradients by e.g. re-introducing tidal influence and by restoring salt marshes should contribute to sustainable development.     

长江流域城市发展的个性与共性问题

建国 50年来 ,长江流域各大、中、小城市发生了巨大的变化 ,特别是城市经济实力、城市性质与功能结构 ,城市生态环境以及区域成绩体系等产生了质的飞跃 ,向着更高层次的城市战略目标发展。从本流域各个城市发展过程与现状特征分析 ,具有五个比较鲜明的个性与共性问题 ,共同构成了长江流域城市化的特征与趋势。本文着重阐述了五个特征 :①城市化的速度 ,比例各省具有自己的鲜明的特征 ;②流域内各省城市空间结构有自己的特点 ;③城市发展条件与形态有自己的个性 ;④城市用地的结构性特点 ;⑤流域内各大中城市的合理发展模式