基于TM影像的面向对象地表覆被信息提取

为验证基于TM影像的面向对象分类方法对复杂地区地表覆被信息提取的可行性,以地处西南地区的渝北为例进行实验。利用样本数据对各个波段的光谱特征进行分析,取得对各波段覆被探测能力的初步认识;基于光谱特征的多尺度分割,运用面向对象分类方法对其分类。面向对象的分类方法总精度和Kappa系数分别为88.42%和0.854 7,将其与监督、非监督分类结果对比分析。结果表明,该方法有效抑制了"椒盐"现象,取得较好的分类结果。     

中国土地发展权的经济分析与配置设计--以北京市平谷区为例

采用综合分析法从土地规划干预的视角对土地发展权进行了经济分析,在此基础上以北京市平谷区为例进行土地发展权的定量配置设计,研究结果表明：（1）在政府有效干预下,土地用途转换所带来在农业用途基础上的价值增值即为土地发展权价值;（2）平谷区土地发展权初始配置为每公顷非基本农田土地发展权数量为0．35个,每公顷基本农田土地发展权数量则为1个,二者均有10％属于国家所有;（3）政府对土地利用干预是土地发展权存在的前提,显现了土地发展权的价值,土地发展权制度的设立又是政府干预的补充;（4）土地发展权在土地所有者和国家之间分配,国家的份额比例相对较小。     

随机森林回归模型在地下水水质评价的新应用

地下水水质评价是地下水研究的一个重要课题,研究更精确、更适用的地下水水质评价模型具有重要意义。近年来应用较多的评价模型存在适用性小、精确度低的问题,其中主要原因在于现有的水质评价标准中,不同因子的等级分类标准不一,同一因子不同等级取值区间不一致等问题,而现有模型无法克服不同因子自身评价等级不匹配以及无法有效处理多重因子之间的相互影响。针对水质评价存在的问题,本文将研究一个能有效克服上述问题,且精确度较高、适用性更广的水质评价模型。基于北京市地下水监测网中污染源监测网的数据,选取大兴区作为研究区域,以大兴区2018年至2020年持续进行监测的39个点位作为研究点,根据监测点历年监测水样,选取化验数据中影响水质环境较为明显的pH值、Cl^-、NO^-₃、SO₄^2-、Na⁺、NH⁺₄、Mn^-、耗氧量(COD_Mn)、总硬度、溶解性总固体这10项指标作为水质评价因子,利用随机森林回归...     

南通海门浅层地下水水化学特征及演化机制

为系统掌握南通海门区浅层地下水水化学现状,在采集区域地下水样本并分析水化学特征的基础上,综合运用描述性统计、相关性分析、Piper三线图、Gibbs模型以及离子比例系数法等分析手段,对南通海门区浅层地下水化学特征及其形成机理进行系统分析。结果表明：HCO3-和Ca2+分别是研究区浅层地下水中占比最大的阴、阳离子;HCO3-Ca和HCO3-Ca·Mg型为该地区主要地下水化学类型;浅层地下水TDS和总硬度的平均质量浓度相对较低,平均值分别为598.00、374.32 mg/L。根据相关性分析,Cl-和Mg2+为影响该区域地下水TDS的特征因子。研究区浅层地下水化学特征主要受到岩石风化作用影响,地下水水质成分主要源自碳酸盐岩和硅酸盐岩等的长期风化溶解。同时,逆向阳离子交换作用也在一定程度上影响着浅层地下水化学的组成。研究结果可为该区地下水开发利用管理提供理论依据和数据支撑。     

Imagineering Uneven Geographical Development in Central Florida

In an era when it is proclaimed that, through globalization, the world has become flat, the unevenness of economic and social development is often overlooked or suppressed. This case study explores the conditions of uneven geographical development in the urban space of central Florida. Focusing primarily on the Reedy Creek Improvement District (RCID), better known to much of the world as Walt Disney World, and on Celebration, the community developed by the Disney Corporation in the 1990s, the relationship between tourism, the defining economic sector in the region, and uneven geographical development is explored. This study shows that the theory of uneven geographical development applies well to a region that is heavily dependent upon the tourist sector for its economy, and thereby works to control the narrative of that space to continue attracting consumers.     

十三陵盖柿营养成分和产地土壤地球化学特征研究

对十三陵盖柿果的营养成分研究表明,柿果中糖度和维生素C含量高,并且富含钾、钠、钙、镁、铜、锌、铁、锰、磷、硫和硼等矿质元素,主产区泰陵、康陵地区的盖柿品质最优。盖柿产地土壤氧化铁、锰、硼、钼、铜、氧化钙、氧化镁、氧化钾和氧化钠含量高,土壤速效钾、有效铜、有效锌、有效铁和有效锰等养分大部分属于富足状态。     

长寿地区Se元素地球化学特征

文章阐述了重庆市长寿区渡舟镇—江南镇一带表层土壤中Se元素的含量水平、空间分布以及Se元素与Pb,Zn,Hg等8个重金属元素、pH值之间的关系。研究区表层土壤中Se元素经迭代剔除后背景均值为0.14×10-6,处于低含量水平;Se含量在城镇区域明显高于农田区域,局部富Se水平;土壤中Se元素分布主要受地层、岩性及土壤对Se元素富集特性的控制,在侏罗系中下统自流井组—新田沟组中,Se元素含量随地层年代由老到新逐渐减少;在侏罗系中上统沙溪庙组—蓬莱镇组中,随地层时代由老到新呈逐渐增加的趋势;随着Se元素含量的升高,As,Cd,Cr,Cu,Pb,Zn元素含量逐渐升高,呈显著正相关关系(P0.01),Hg,Ni元素含量略具升高趋势,而pH值则无明显升降,相关性不明显。     

Glacier shrinkage and negative mass balance in the Chilean Lake District (40°S) / Rétrécissement glaciaire et bilan massique négatif dans la Région des Lacs du Chili (40°S)

Abstract

Ice-capped volcanoes of the Chilean Lake District have shown significant glacier retreat during recent decades, probably in response to tropospheric warming and precipitation decrease. Volcán Mocho-Choshuenco (39°55′S, 72°02′W) is one of the main active volcanoes in this part of the country. A mass balance programme was initiated on its southeastern glacier in 2003, in view of its representative conditions as an ice body that is presumably not affected by current volcanic activity. The glaciers of this volcano have been retreating and shrinking in recent decades; by 2003 there had been a reduction of 40% of the original area of 28.4 km² in 1976. A maximum decrease of area was observed in the most recently analysed period, a rate of 0.45 km² year^-1 between 1987 and 2003. The glacier average net mass balance of 2003/04 yielded ?0.88 m w.e. (water equivalent) per year (±0.18), with an average net accumulation and ablation of 2.59 and ?3.47 m w.e. per year, respectively. This is the first direct measurement of glacier mass balance in southern Chile, where very little is known about glacier variations and glacier–volcano interactions.     

Testing the model of oblique transpression with oblique extrusion in two natural cases: Steps and consequences

Kinematic models of various types of transpression have been used to explain fabric features and strain in many natural deformation studies. Here, a mathematical model that encompasses all monoclinic and triclinic transpressional deformations including triclinic deformation with inclined simple shear (ϕ) and/or inclined extrusion orientations (υ) can be tested using a step-by-step approach with available field evidence. Two cases are presented. The first case from the Wabigoon–Quetico boundary in the Archean Superior Province utilizes both fabric orientation and quantified strain data. The best fit of the field evidence to the model indicates that deformation likely took place along subvertical shear zones via transpression with subhorizontal simple shear (ϕ = 0–20°) and variable inclined extrusion direction (extrusion can be either east or west and υ typically indicates extrusion orientations between 0 and 50° from vertical). The second case of the South Iberian shear zone has fabric orientation data, but no quantifiable strain possibilities. The best fit of the field evidence to the model indicates that deformation likely took place along a moderately inclined shear zone via transpression with subhorizontal simple shear (ϕ = 0–20°) and variable inclined extrusion direction (υ values between 0° and 80° from the true dip of the shear zone). Using this protocol in other examples of natural deformation will allow further constraints to be applied to kinematic models.     

旅游驱动的乡村振兴实践及发展路径

归纳案例地为摆脱贫困适应时代需要的具体实践过程,从“三个转向”（产业转向、管理转向、空间转向）解析旅游驱动的乡村振兴实践,总结旅游业驱动乡村振兴的一般机制及路径,为理解旅游业在乡村振兴中发挥的作用提供新视角。研究发现：① 发展旅游业是旅游资源富足的贫困地区脱贫致富,实现乡村振兴的主渠道和中坚力量;② 武陵源区主导产业由林业转向旅游业这一过程,为实现乡村振兴实践提供动力基础;景区经营权与管理权的分离,促进乡村经济的发展;“景区游,城区住”的格局加速了武陵源区乡村振兴的步伐;③ 武陵源区在长期发展实践中形成了“旅游产业发展→旅游小镇发育壮大→乡村振兴→城乡融合”之实践模式;④ 加快推进旅游业态创新,不断增加农民收入,加强乡风建设,以政府为主导,加速基础设施建设是资源富足贫困地区实现乡村振兴的必由之路。