浅谈永久基本农田的划定

划定永久基本农田是党的十七届三中全会提出的新概念和新举措。本文从宏观层面对落实好永久基本农田的划定进行探讨,为切实加强基本农田保护与建设提供思路。研究表明,要落实好永久基本农田的划定,首先应从战略高度,将我国传统农区的大面积、集中连片、优质高产基本农田规划建设为永久基本农田集中区,同时重点做好市域永久基本农田的划定,并建立划定永久基本农田的激励机制。     

叠加法在征地区片综合地价评估中的应用分析

叠加法是《农用地估价规程》中重点推荐的征地区片综合地价评估方法。但在2005年国土资源部征地区片综合地价评估技术规范中并不主张采用该方法。本文试图从叠加法的原理入手,结合征地区片综合地价评估实践,研究叠加法在征地区片综合地价评估中的应用问题。研究表明,若能合理处理相关问题,叠加法是目前条件下征地区片综合地价评估中一种较为理想的方法。     

补充耕地数量质量按等级折算研究进展

运用文献资料法和因果分析法,研究补充耕地数量质量按等级折算的发展过程和发展方向。研究结果表明,补充耕地数量质量按等级折算经历了政策提出、基础工作、试行等阶段,今后的发展方向是积极推进补充耕地数量质量按等级折算工作和完善补充耕地数量质量按等级折算的技术体系。得出已经具备了全面实行补充耕地数量质量按等级折算的各项条件的研究结论。     

三峡库区建设用地利用的经济效益评价——以重庆市云阳县为例

重庆市云阳县地处三峡库区的腹心地带,地形地貌极其复杂,其土地利用在三峡库区有一定的代表性。本文以重庆市云阳县为重点研究对象,首先对其建设用地的利用现状及历年动态变化情况进行分析,其次选取三峡库区以万州区、梁平县、丰都县等有代表性的10个区县为对比研究对象,提炼经济效益评价指标,综合评价云阳县在整个三峡库区中的建设用地利用的经济效益水平,最后提出相应的促进建设用地集约利用的对策。研究成果显示了云阳县及三峡库区其他区县建设用地利用的经济效益水平,可为三峡库区促进建设用地节约与集约利用,确定土地利用方向提供借鉴。     

旅游用地分类的探讨

本文在界定旅游用地概念的基础上,分析了目前全国土地分类体系中有关旅游用地分类的不足和缺陷,并对旅游用地进行了重新分类,初步建立了旅游用地分类新体系,为协调旅游用地与其他用地之间的关系提供较为科学的理论依据。     

基于征地区片的农地价格矫正研究——以泰州市为例

随着我国经济的高速发展,越来越多的农用地被征收和征用为建设用地,因此征地的补偿对广大农民来说就显得至关重要。虽然国家已经取消了征地补偿的最高标准,并逐步推广了同地同价的征地区片综合地价,但和市场价格相比,还有很大的差距。本文通过理论与实证研究建立征地区片单元的单元分值与样点地价的关系模型,测算不同级别的区片价格,与现行标准的征地区片价进行比较,验证了目前的征地区片价是扭曲的,并提出了相应的建议。     

兵团建设用地集约利用综合评价研究

土地集约利用水平综合评价直接反映土地利用的集约程度。文章对兵团建设用地集约利用水平综合评价的方法进行了有益的探索,构建了一套土地集约利用水平综合评价的指标体系,从宏观上对兵团建设用地集约利用水平进行了分析和评价,并提出促进土地集约利用的建议。     

干湿循环对旱区铁路桥梁性能劣化的影响

在对干旱地区铁路普通钢筋混凝土桥梁病害调查的基础上,分析了导致梁体钢筋锈蚀和保护层开裂的主要原因。通过实验验证了旱区大气环境下干湿循环对钢筋锈蚀的加速作用,针对目前梁体构造特点提出了整治和改进建议。     

Changes of Major Lakes in Central Asia and Analysis of Key Influencing Factors

The five Central Asian countries are located in the inland areas with a serious shortage of water resources and the lakes are the main support for the ecosystem in the area.Due to the lack of long-term information support both in the year and in the intervening years，it is difficult to fully understand the characteristics of the major lakes in the five Central Asian countries.In this study，MODIS 8-day reflectivity products were used as data sources from 2001 to 2016，and the Normalized Difference Water Index (NDWI) method was used to extract the water body area.The annual and inter-annual water surface of 9 major lakes in Central Asia Change Characteristics and Key Influence Factors.The results show that:(1) Lake water surface changes in the five Central Asian countries are affected by anthropogenic disturbance and climate change.The annual and interannual time series of the lake tail and alpine enclosed lake show different trend and fluctuation characteristics;(2) the changes of the Aral sea in the south and north are most obvious.The surface area of the South Aral Sea has decreased obviously in recent 15 years，reducing the area by more than 70%，while the North Aral Sea fluctuates with the variation of precipitation.(3) the total area of the sub-main lakes has been declining.The area has shrunk by 23.51% over the past 15 years.The South Aral Sea is a contributor to the statistical decrease of all lakes.However，the surface area of other lakes shows an increasing trend.     

Fatty acid methyl esters (FAME) from oleaginous seeds grown in arid lands. Part II: Ibicella lutea,Onopordum nervosum,Peganum harmala,Smyrnium olusatrum and Solanum elaeagnifolium

The properties of fatty acid methyl esters (FAMEs) obtained from Tunisian oleaginous seeds, grown in arid places with no need of supplementary water, are studied to assess their potential use as biodiesel: devil horn Ibicella lutea, cotton thistle Onopordum nervosum arabicum, Sirian rue Peganum harmala, horse celery Smyrnium olusatrum and silverleaf nightshade Solanum elaeagnifolium. Some key properties such as cloud point, pour point, cold filter plugging point, oxidation stability, cetane number, density, kinematic viscosity, heating value and oxygen extended sooting index have been predicted using equations that correlate the above properties with their ester profiles.