浅谈科学发展观与草地生态建设

草地退化是我国天然草地面临的突出问题。我国草地占据了农牧交错带和绿洲-荒漠交错带,对人为活动具有较强的敏感性和生态脆弱性,因此在草地生态建设方面要坚持以人为本,树立全面、协调、可持续的科学发展观,统筹人与自然的和谐发展,充分发挥草地的自然修复能力,建设人工草地,合理的对草地进行开发和利用,完善草地的生态建设,使草地朝着有利于人类生存和发展的方向演变。     

论韶关地区道路绿化植物的科学选择与配置

韶关地区道路绿化树种大多数是从南部珠三角地区和北部湖南地区引进，可能存在所引进树种是否适应韶关气候的问题。因此，如何运用科学的方法选择与配置道路绿化植物和确定合适的种植位置就成为道路绿化工程的关键。     

食物安全的内涵、指标与评价方法综述

食物安全问题一直是国内外研究的热点。目前,全球食物安全面临严重挑战,前景并不乐观。作为世界上人口和食物消费最大的国家,中国的食物安全面临更大挑战,但对其认识学术界还存在争论。为了准确把握食物安全的内涵,科学评价中国食物安全的状况,首先分析了食物安全概念的演变,然后总结了评价食物安全状况的供需平衡指标、消费指标、营养指标、综合指标,以及评价粮食安全状况的常用指标。随着人民生活水平的提高,中国的食物结构发生了根本的改变,因此,今后食物安全的研究应由单纯的粮食安全转向包括所有食物种类的食物安全,内容应更注重食物综合保障能力及营养安全。     

Flow alteration and thermal pollution depress modelled growth rates of an iconic riverine fish,the Murray cod Maccullochella peelii

The serial discontinuity concept (SDC) proposes that hypolimnetic‐releasing impoundments cause major disruptions to the naturally occurring physical, chemical and biological gradients of rivers but that this impact diminishes with distance downstream. Such a gradient in discharge, flow velocity and temperature regime occurs below a large hypolimnetic‐releasing impoundment, the Hume Dam, on the River Murray in south‐eastern Australia. To examine the effects of this disturbance gradient on a warm‐water large‐bodied freshwater fish, the Murray cod (Maccullochella peelii), a bioenergetics model was developed and calibrated to explore energy expended under differing water velocities and temperature regimes. Model simulations predicted negative growth of juveniles directly downstream of the impoundment, due largely to the energetic costs associated with active and, to a lesser extent, standard metabolism outweighing the achievable energetic gains through food consumption. As flow velocity and temperature regimes became more favourable downstream, so did the simulated growth of the species. It was not until +239 km downstream of the impoundment that the model predicted that flow velocity and temperature regimes were suitable for greater weight gains. The modelled growth responses of juvenile Murray cod are consistent with the predictions of the SDC, emphasising that changes in the bioenergetics of individuals are likely to be reflected in reduced growth rates under the changed flow velocity and temperature regimes imposed by disturbance gradients. This research represents a valuable step in the biological understanding of Murray cod within variable riverine environments and emphasises the urgency required to mitigate impacts associated with hypolimnetic impoundments.     

基于Cruise的纯电动汽车的参数匹配与仿真

对某款纯电动汽车的驱动电机参数、传动系统参数、电池组参数等进行参数匹配选型,并借助汽车仿真软件AVL Cruise(Cruise是一款在业界功能最强大、最稳定,适用性最广的整车和传动系统性能分析的仿真工具)进行动力性能仿真分析。经过仿真验证之后,该参数匹配过程正确,动力性能达到设计的要求。     

The Construction Strategy of Small Towns Based on Ecological Concept

Based on the perspective of ecological concept,this study first interpreted the background of ecological civilization construction,and combed the relationship between ecological concept and small town planning.Second,it expounded the ecological problems of natural resources,economic development,landscape system,social humanities and other aspects in the construction of contemporary small towns.According to the study,the construction of small towns based on the ecological concept should establish the concept of "ecology first",practice "multiple compliance",coordinate the relationship with other planning,make reasonable planning and design in the aspects of town scale,functional orientation,structural form,road traffic,landscape style and features,humanistic characteristics,and strengthen the implementation,supervision and management of planning.Finally,summary and outlook was made,hoping that the study will be of reference value and guidance to the planning and construction of small towns.     

天津市产业碳排放的影响因素及贡献

[目的] 综合考虑“水—土—能—碳”相互关系，研究产业碳排放的影响因素及贡献，为天津市减排决策制定提供一定依据。[方法] 对天津市产业碳排放进行测算，将水土资源因素引入Kaya恒等式，运用LMDI模型计算产业碳排放各影响因素的贡献。[结果] 2004—2018年天津市各产业碳排放均呈现上升趋势；整体来看，水资源经济产出、人口数量促进天津市各产业碳排放，且前者为主要促进因素，水土资源因素抑制各产业碳排放，碳排放强度促进农业碳排放，而抑制其他产业碳排放，人均用地面积抑制农业碳排放，而促进其他产业碳排放；水土资源因素对各产业碳排放影响的变化与水土资源匹配度变化有较好的一致性，单位用地面积用水量越多，其对碳排放的促进作用越大。[结论] 为实现节能减排，应发展节水产业，优化城市水土资源开发利用，发挥水土资源因素对碳排放的抑制作用。     

盐土农业及研究进展

综述了盐土农业新理念的产生、定义、特点及其国内外研究进展。     

分块子空间追踪算法

压缩传感理论是一种充分利用信号稀疏性或者可压缩性的全新信号采样理论。该理论表明，通过采集少量的信号测量值就能够实现可稀疏信号的精确重构。本文在研究现有经典重构算法的基础上，提出结合图像分块思想和回溯思想的分块子空间追踪算法（Block Subspace Pursuit, B_SP）用于压缩传感信号的重构。该算法以块结构获取图像，利用回溯过程实现支撑集的自适应筛选，最终实现图像信号的精确重构。实验结果表明，在相同测试条件下，该算法的重构效果无论从主观视觉上还是客观数据上都有不同程度的提高。     

乡村旅游环境承载力概念探讨

近年来乡村旅游的兴起以及旅游业的空前繁荣,使人们的环境意识日益增强,人们开始探讨旅游环境承载力,但是少有人研究特定乡村旅游环境承载力,通过对现有旅游环境承载力研究的分析,提出乡村旅游环境承载力概念。