Study on Soil Erosion Model Under Different Slopes in Southwest Karst Mountain Area

The aim was to further research soil erosion characteristics and accurately predict soil erosion amount in karst areas. Based on field surveys and research achievements available, yellow soils, which are widely distributed, were chosen as test soil samples and slope, rain intensity, vegetation coverage and bare-rock ratio were taken as soil erosion factors. Artificial rain simulation instruments （needle-type） were made use of to simulate correlation of rain intensity, vegetation coverage, and bare-rock ratio with soil erosion quantity. Furthermore, multiple-factor linear regression analysis, stepwise regression analysis and multiple-factor non-linear regression analy- sis were made to establish a multiple-factor formula of soil erosion modulus with dif- ferent slopes and select regression models with high correlation coefficients. The re- sults show that a non-linear regression model reached extremely significant level or significant level （0.692〈FF〈0.988） and linear regression model achieved significant lev- el （0.523〈FF〈0.634）. The effects of erosion modulus changed from decreasing to in- creasing and the erosion factors from high to low were rain intensity, vegetation cov- erage and bare-rock ratio when slope gradient was at 6~, 16~, 26~ and 36~. The mod- el is of high accuracy for predicting gentle slope and abtupt slope, which reveals correlation of erosion modulus with erosion factors in karst areas.

Geographical Differences and Influencing Factors of Rural Energy Consumption in Southwest Mountain Areas in China:A Case Study of Zhaotong City

China is a mountainous country,and Southwest mountain areas cover the most mountain areas in China and have the most serious problems.Taking Zhaotong city as the study area,based on 902 rural household questionnaires of 11 villages in 2 counties and Tobit model,this paper analyzes the geographical differences and influencing factors of energy consumption for non-production purposes of rural households living in different terrain conditions.This research finds that:(1) Coal takes up the main part of energy consumption in valley areas and coal consumption is mainly affected by per capita cultivated land area,household income,proportion of rural household energy expenditure in total expenditure,coal price,and family population size.Firewood takes up the main part of energy consumption in high mountain areas and firewood consumption is mainly affected by per capita firewood forest area,distance to purchase coal,household income,electricity price,and coal price.(2) Only when the distance is greater than 20 kilometers,that is the average distance of rural households living in middle mountain areas(1,600m^1,800m) to purchase coal,the transportation condition has a significant impact on coal consumption.(3) In high mountain areas,prices of coal and electricity are the main factors influencing energy consumption choice of rural households.Too high prices of coal and electricity would to some extent lead rural households to choose firewood as the main energy consumption type.Compared to coal,rural households prefer to choose electricity.

Characteristics and distributions of humic acids in two soil profiles of the southwest China Karst area

Characteristics and distributions of humic acid(HA) and soil organic matter(SOM) in a yellow soil profile and a limestone soil profile of the southwest China Karst area were systematically investigated to reveal their evolutions in different soils of the study area. The results showed that characteristics and distribution of SOM along the two soil profiles were notably different. Total organic carbon(TOC) contents of soil samples decreased just slightly along the limestone soil profile but sharply along the yellow soil profile. TOCs of the limestone soils were significantly higher than those of the corresponding yellow soils, and C/N ratios of SOMs showed a similar variation trend to that of TOCs, indicating that SOM can be better conserved in the limestone soil than in the yellow soil. The soil humic acids were exhaustively extracted and further fractionated according to their apparent molecular weights using ultrafiltration techniques to explore underlying conservation mechanisms. The result showed that C/N ratios of HAs from different limestone soil layers were relatively stable and that large molecular HA fractions predominated the bulk HA of the top soil, indicating that HA in the limestone profile was protected while bio and chemical degradations were retarded. Combined with organic elements contents and mineral contents of two soils, weconcluded that high calcium contents in limestone soils may play a key role in SOM conservation by forming complexation compounds with HAs or/and enclosing SOMs with hypergene CaCO_3 precipitation.

Accumulation and risk assessment of heavy metals in dust in main living areas of Guiyang City, Southwest China

Guiyang is a famous tourist city located in southwestern China. In this study, dust from eleven residential areas, seven city squares, and nine schools was collected to measure the heavy metal levels and evaluate its risk. At each sampling site, 4–5 sub-samples were taken as a bulk sample. All samples were air-dried, ground, passed through a 0.105 mm nylon sieve, digested with HNO3-HClO4 to determine the concentrations of Cd, Cu, Ni, Pb and Zn by ICP-MS, and digested with 1:1 aqua regia to determine As by AFS. The results show that the concentrations of As, Cd, Cu, Ni, Pb and Zn in dust of Guiyang City follow normal distribution with means of 16.1, 1.54, 138, 47.7, 129 and 479 mg/kg, respectively. Levels of As, Cd, Cu, Ni, Pb and Zn exceed the background level of soil in Guizhou Province by 33%, 96%, 100%, 78%, 96%, and 100%, respectively. Cd, Cu, Pb and Zn are heavily accumulated in dust of living areas with accumulation factors of 4.10, 5.12, 4.12 and 5.51, respectively. City square possesses the highest geometric means of As, Cd, Cu, Pb, and Zn. The risks of heavy metal exposure to teenagers are not obvious and in an order of As>Pb>Cu>Ni>Zn(Cd).

Analysis on Characteristics of Architectural Environment of Traditional Villages in Southwest Mountainous Area:Taking Heijing Ancient Town of Chuxiong as an Example

The formation of the ancient town of Heijing conforms to the natural conditions and local conditions,and makes effective use of the natural mountains,water bodies,trees and other resources of the ancient town,so that the ancient town and nature rely on each other and unify harmoniously.Through the analysis of the environmental characteristics of the ancient town,this paper further explores its cultural connotation.

Analysis on Supported Employment of People with Disabilities in Southwest China's Minority Areas

Employment of people with disabilities in Southwest China’s ethnic minority areas is characterized by relatively high pressure, a poor environment and single form. Supported employment can solve the problems faced by people with disabilities in the ethnic minority areas of Southwest China. Therefore, it is of practical significance to promote such a new form of employment. But in promoting the development of supported employment, it is necessary to strengthen its local top-level design and to establish corresponding legal and policy systems so as to give full play to the positive role of the government and establish a strong support system.

CONSULTATIVE RECOMMENDATIONS ON SUSTAINABLE DEVELOPMENT IN KARST AND ROCK-NAKED MOUNTAIN AREAS OF SOUTHWEST CHINA

The serious degradation of the ecological environment and the rapid expansion of stone desert have had a serious effect on the economic development of karst and rock-naked mountain areas in Southwest China. Moreover, these areas are still at the initial stage of industrialization, characterized by a greater significance of agriculture to the economy, face sharp contradictions among the population, the arable land and resources, and are suffering because of a shortage of investment. On the basis of this current situation, three recommendations are made in this article: "coordinating the relations among grain, ecology, population and economic development", "increasing the input of science and technology", and "adopting policies consistent with social equity in areas of poverty".

西南山区铁路客运专线隧道底鼓病害变形监测研究

西南山区铁路客运专线具有高桥隧比、沿线地质条件复杂恶劣等特征,在建设和运营过程中易出现各类工程病害。文章基于某隧道底鼓变形病害,设计并开展包含围岩变形、仰拱受力和道床板沉降变形3个监测指标的隧道变形监测方案。通过对监测数据进行分析,获取隧道和围岩受力变形的演化规律,据此提出后续加密轨道几何形位静态、动态检测和衬砌结构贯通裂缝观测、实施列车降速运行等处理措施。相关研究可为该客运专线的安全运营提供有力保障,同时为类似工程隧道病害的监测和整治工作提供有益参考。

景观功能视角下的西南山区农业景观格局演变研究——以重庆市石柱县为例

鉴于中国西南山区农业生态环境的脆弱性与敏感性,解析该地区农业景观时空演变特征对合理利用农业景观资源和保护生态环境具有重要的理论意义.以重庆市石柱县为例,采用景观利用图谱、地形位分布指数、景观转移矩阵等方法,从景观功能视角开展西南山区农业景观格局演变特征分析.研究表明:①农业景观呈现出“三增一减”的变化趋势,即生活型和拓展型农业景观面积呈增长态势,生态型农业景观面积呈波动变化趋势;生产型农业景观面积持续下降.农业景观变化主要表现为生产型向生态型、生活型、拓展型农业景观转化;生态型向生活型、生产型、拓展型农业景观转化.②石柱县生态型农业景观主要分布在高等级地形位,生产型农业景观逐渐向高程和坡度较高的地形位移动,生活型农业景观主要分布在低、中低等级地形位上,拓展型农业景观逐渐向较高地形位转移.③坡度、高程等是导致研究区农业景观格局演变的主要环境因素;而农业人口、农民人均纯收入、第一产业占比等是农业景观格局演变重要的人文驱动因素.

西南山区乡村贫困地域系统时空演化格局研究——以云南省镇沅县为例

在梳理总结国内外关于贫困地理与农村多维空间贫困、乡村地域系统与贫困地域系统理论前沿研究的基础上,提出“乡村贫困地域系统”研究视角,并对乡村贫困地域系统理论内涵进行了初步探析.以云南省镇沅县109个村域为评价分析单元,构建了乡村贫困地域系统演化发展评价指标体系,设计了乡村贫困地域系统演化发展指数测度模型和基于“时空立方体—新兴时空热点分析”的时空演化模式识别方法.研究显示:(1)镇沅县2013-2021年乡村贫困地域系统演化时序阶段性特征经历了“差异波动演化(2013-2015年)—快速演化(2016-2019年)—增长滞缓趋稳(2020-2021年)”3个主要阶段.(2)镇沅县乡村贫困地域系统时空演化模式以连续热点模式为主,加强的热点模式呈零星分布,表征2013-2021年镇沅县乡村贫困地域系统整体上经历了较快且连续稳定的减贫演化过程,是减贫政策普惠作用在时空演化模式上的具体表现;连续冷点模式和持续冷点模式呈现出县域东西两端集聚分布态势.(3)多维空间贫困陷阱主要集中在和平镇、者东镇、振太镇的部分村域,相关村域脱贫稳定性相对较差、返贫风险较高.乡村发展是乡村地域系统循环累积与动态演化的结果,深入刻画分析乡村贫困地域系统时空演化格局与特征,对于科学推动脱贫地区转型发展具有重要意义.

西南高山峡谷区水土流失综合防治技术与示范

西南高山峡谷区覆盖大横断“七脉六江”地区,是国家“三区四带”重要生态安全屏障,对保障国家生态安全和区域高质量发展具有重要作用。针对西南高山峡谷区存在的水土流失分异演变地带性规律及其关键驱动机制,水土流失对农业耕作、高陡地形、岩溶地质及冻融作用等复杂驱动条件的响应及其防控机制,民族聚集区生态系统服务功能整体提升及生态生产协同的理论与对策等问题,选取兰坪、云龙、永胜、康定以及波密县为典型示范区,开展国家重点研发计划活动,以西南高山峡谷不同类型区水土流失分异规律和综合防治为主线,按照三个层次开展水土流失综合防治与示范研究,攻克高精度土壤侵蚀预报模型与监测技术瓶颈,形成生态系统服务整体提升的“水土流失防治-生态系统服务-民族经济发展”的多目标水土流失综合防治技术体系,最终为西南高山峡谷区生态系统恢复提供科学依据与技术支撑。

数字赋能西南边境地区返乡创业帮扶的影响机理、现实问题与实践进路

返乡创业是西南边境地区由“输血式”帮扶向“造血式”帮扶转变的重要方式。通过数字赋能提升西南边境地区返乡创业帮扶的整体效能,是该区域进一步巩固脱贫攻坚成效的有效路径之一。结合数字技术的特殊属性,返乡创业的多元特征及西南边境地区的独特区位,剖析数字赋能对西南边境地区返乡创业帮扶的影响机理,发现数字赋能创业活动的结构效应促进了西南边境地区返乡创业帮扶的边界扩展,数字赋能开放合作的共享效应促进了西南边境地区返乡创业帮扶的资源整合,数字赋能多元领域的协同效应促进了西南边境地区返乡创业帮扶的权力重塑,数字赋能技术融合的创新效应促进了西南边境地区返乡创业帮扶的柔性运行。同时,数字赋能在西南边境地区返乡创业帮扶过程中存在着经济基础与要素需求的落差、人才问题与数字帮扶应用与创新的矛盾、西南边境特殊区位与数字赋能返乡创业帮扶的协调等现实问题。研究认为,应加强政策引领,促进要素流入,为数字赋能返乡创业帮扶提供保障;完善人才机制,推进数字人才与数字赋能返乡创业帮扶的有效衔接;对接优势资源,通过边境特色嵌入实现返乡创业帮扶的成效增值等策略。

西南民族地区农业现代化时空分异特征及影响因素分析

【目的/意义】民族地区是中国扶贫工作开展的主战场,推动该地区农业现代化发展有助于实现其产业振兴,促进经济社会发展。【方法/过程】从农业产业、农业生产、农业经营和农业生态环境4个层面构建西南民族地区农业现代化评价指标体系,运用多指标综合测度法、障碍度模型和空间计量模型,分析该地区的农业发展状况,并探究农业现代化发展的内外部影响因素。【结果/结论】研究发现:(1)西南民族地区农业现代化水平随时间呈逐步提升趋势,各省份发展水平在空间上呈正相关集聚;(2)内部制约因素随时间推移发生改变,农户收入偏低、农业技术水平落后以及生态环境脆弱等问题较为突出;(3)自然资源禀赋和农业产业结构对研究区农业现代化具有显著正向空间溢出,经济发展水平则呈现负向空间溢出。基于此,从推动三产融合、提升基层农技人员数字素养、持续开展农药化肥减量增施有机肥行动、构建区域利益共享机制等方面提出相应对策建议。

西南山区高速铁路非正常情况下列车运行调整探讨

西南山区与平原地区的地域特点存在显著差异,高速铁路运输组织在装备上、组织上、要求上明显不同。通过分析西南山区高速铁路非正常情况下列车运行调整类型,按轻微事故及严重干扰事故类型进行模型构建。以成渝高速铁路列车运行调整为例,计算验证结果表明,该模型求解速度快,具有较高的求解质量,对西南山区高速铁路非正常情况下干扰列车运行的不同场景均有一定的适应性,为提高山区高速铁路运行的安全系数提供支撑。

“自然-人文”融合视角下的西南山区小流域划分与整合

【目的】采用“自然-人文”融合的视角,结合人文要素界定小流域划分阈值,强化小流域划分研究的人文特征,为以小流域为基本单元的山区开展国土空间开发和社会经济建设提供区划方案支持。【方法】根据小流域自然水文过程和人文属性因素,利用流域面积法结合均值变点法及边界重叠度概念,以我国西南山区为例,对研究区内6个流域试验区进行小流域划分阈值测算,在得到最佳阈值的基础上,对西南山区以小流域为单元进行划分,并整合划分结果,分析、整合结果的数量与空间特征,提出一种山区小流域划分的融合方法。【结果】①西南山区小流域划分的最佳阈值为30.00 km^(2);②西南山区小流域数量为16075个,面积范围为25.07~431.82 km^(2);③从面积来看,小于50.00 km^(2)的小流域为8702个,占比54.13%,介于50.00~100.00 km^(2)的小流域为5358个,占比33.33%,大于100.00 km^(2)的小流域为2015个,占比12.53%,基本符合当前水利部要求。【结论】通过西南山区实测验证,本研究提出的山区小流域划分与整合方法在结果上能体现小流域的自然与人文属性特征,较好符合当前山区组织单元管理的需要,可为山区小流域区划提供方法借鉴。

西南高山峡谷区水力侵蚀时空变化及其驱动力

[目的]确定西南高山峡谷区水力侵蚀的空间分布及其时空变化特征,探究区域水力侵蚀的驱动机制,并为区域水土流失治理提供对策。[方法]基于GIS和RUSLE模型,利用Sen趋势分析和Mann-Kendall显著性检验法、随机森林回归对西南高山峡谷区水力侵蚀的时空演变特征以及驱动力进行分析。[结果](1)西南高山峡谷区水力侵蚀微度和轻度侵蚀占比78.05%以上。(2)整体上,2000—2020年水力侵蚀量变化范围为4.606 3×10^(8)~1.487 4×10^(9) t,多年均值为7.966 4×10^(8) t。降雨侵蚀力因子变化范围为125.11~249.93 MJ·mm/(hm^(2)·h·a),多年均值为186.71 MJ·mm/(hm^(2)·h·a)。植被覆盖与管理因子变化范围为0.37~0.70,多年均值为0.48。(3)整体上坡度坡长因子对西南高山峡谷区水力侵蚀空间分异的解释程度最高,达到41%,其次是植被覆盖与管理因子,达到24%,其余是降雨侵蚀力因子>土壤可蚀性因子>水土保持措施因子,分别达到16%,12%,8%,且各因子对水力侵蚀空间分异的解释程度随着水土保持分区的不同而出现差异。[结论]西南高山峡谷区侵蚀严重的区域主要分布于藏东—川西高山峡谷生态维护水源涵养区南部,藏东南高寒高山峡谷生态维护区西北部、东部。坡度坡长因子及植被覆盖管理因子是西南高山峡谷区水力侵蚀空间分布的主要驱动因素。藏东—川西高山峡谷生态维护水源涵养区、藏东南高寒高山峡谷生态维护区和滇西北高山峡谷生态维护区,建议改善此区域植被覆盖,提高土壤抵抗侵蚀能力;滇北—川西南高山峡谷蓄水保土区建议在改善植被覆盖的基础上,在生态脆弱的区域布置适当水土保持措施。

西南石漠化地区粮食作物时空变化及影响因素研究

【目的】分析西南石漠化地区粮食作物播种面积的时空变化特征及影响因素。【方法】基于2015—2020年西南石漠化地区粮食种植数据与社会经济指标数据,运用农作物种植结构类型指数、空间自相关、空间误差回归模型等模型方法,在县域尺度上进行研究。【结果】2015—2020年粮食播种面积呈波动性增加趋势,玉米播种面积整体下降,稻谷和薯类播种面积整体上升;粮食种植结构类型共有54种,区域种植结构类型丰富度指数波动上升,玉米型县域数目减少,稻谷型增加;云南省石漠化地区HH集聚区的粮食作物为玉米与薯类,广西石漠化地区HH集聚区粮食作物为玉米与稻谷,而在贵州省石漠化地区,3种粮食作物分别有相应的HH集聚种植区;此外,自然地理环境、总人口、居民可支配收入、产业发展是影响西南石漠化地区粮食、玉米、稻谷、薯类播种面积的主要因素,亩均利润对玉米播种面积具有显著正向效益,国家政策促进了西南石漠化地区玉米面积的调减与种植结构的改变。【结论】2015—2020年西南石漠化地区主要受国家政策影响,减少玉米非优势区的播种面积,优化了该区域的种植结构。

西南山区农作物秸秆收运处理“三位一体”体系构建与实践——以云南省B市L区为例

秸秆是农业生产过程中重要的附属资源,现阶段,西南山区因地形与经济问题、农户环保和秸秆资源化意识薄弱问题、秸秆高值化利用市场不健全等问题,造成秸秆收集困难,使秸秆未得到及时有效的利用,主要原因是秸秆收储运体系建设相对滞后,影响了秸秆资源化利用和高值化发展进程。根据其制约因素,本文提出“三位一体”秸秆收储运体系,建立专业化收储运网络体系,减少秸秆焚烧和随意丢弃,有效的促进西南山区秸秆资源利用的高值化发展。

音频大地电磁法在黔西南金矿区域地电特征研究中的应用

黔西南地区是我国重要的卡林型金矿分布区,区内台地和盆地沉积格局交替频繁,金矿成矿主要受褶皱和断裂构造控制,查明该区地层分布及构造展布特征对于该区金矿找矿具有重要意义。本文以黔西南金矿区为研究靶区,分别进行了音频大地电磁法(Audio Magnetotelluric Method,AMT)在台地相、盆地相不同模式的正反演计算,基于优选的反演模式在区内实地开展了音频大地电磁法的应用研究,取得主要结果与认识:①台地相区地层电性差异明显,基于TE&TM联合反演模式的AMT能有效区分地层、查明断裂构造空间展布特征;②受上部厚低阻层影响,AMT在盆地相区地层区分性弱,基于TM反演模式的AMT能清晰反映褶皱、断裂构造空间展布特征;③黔西南金矿区域地质条件复杂,因地制宜的优选AMT反演模式是实现该区地电结构精细刻画的关键。研究成果与区内实测断层、钻探工程等验证结果吻合较好,充分体现了AMT在该区查明地层分布及构造展布特征的有效性;另一方面进一步明确了黔西南金矿区域台地相、盆地相AMT反演模式,对后人利用AMT在该区及相近地区实现金矿找矿突破具有重要的参考价值。

鲁西南黄泛区耕地格局变化特征及其影响因素

[目的]探讨鲁西南黄泛区耕地的空间格局、变化特点及其影响因素,为区域耕地保护提供科学依据。[方法]基于2m高分遥感影像,结合野外调查和《菏泽市统计年鉴》,采用遥感解译、重心模型、冷热点分析、地理探测器等方法,分析2019—2022年鲁西南黄泛区耕地空间分布、重心迁移、年际变化特征及影响因素。[结果](1)2019—2022年鲁西南黄泛区耕地面积占区域60%以上,每年均存在耕地流失现象,流失面积呈现逐年递减趋势,郓城县耕地面积减少最多,达18.28 km^(2),鄄城耕地动态度变化最大,达-2.26%;耕地重心整体向东北方向迁移。(2)耕地流出面积高于流入面积,主要流出方向和流入方向均为建设用地和林地,耕地变动最集中的区域主要分布在曹县南部。(3)对耕地变化影响最强的单因子是农村从业人员(X_(5)),最强的双因子交互组合是农村劳动力资源数(X_(4))和城镇居民人均收入(X_(6))。[结论]鲁西南黄泛区2019—2022年耕地流失是经济社会因子为主的多因子综合作用的结果。