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LUO Hao DENG Li JIANG Songlin FU Erkang MA Jun SUN Lingxia JIANG Mingyan CAI Shizhen JIA Yin CAI Jun LI Xi 《资源与生态学报(英文版)》2021,12(3):384-396
Natural environments contribute to people’s perception, preference and health restoration. Many researchers have focused either on the positive effects of overall rural environments on stress recovery or concentrated on the perception and preference aspects of the rural landscape, but few have integrated perception, preference and stress recovery simultaneously. This paper developed a framework which includes 11 elements and 38 element components related to Linpan, China, and distributed it online as part of a survey. As a result, a total of 324 valid questionnaires were collected. The questionnaire included demographic details, perception and preference degree for Linpan, as well as self-estimations of stress recovery. Stepwise multiple linear regression was employed, and revealed 16 significant predictors for the perception, preference and stress recovery in rural environments. In terms of elements, atmosphere and imagery were the two elements that could be best perceived, while woodland, farmland, water, residence and road were the five most important elements for the preference. Moreover, seven elements were also identified as significant predictors for stress recovery. Among the element components, tranquility as well as road and water proximity were the two significant predictors for perception, while wide visibility as well as woodland and residence blending contributed significantly to stress recovery. The five element components of woodland interior, vegetable field, stream, courtyard space and branch road each had a significantly predictive ability for preference and stress recovery. These findings extend the understanding of the perception, preference and restorative properties of rural environments through the combination of elements and element components in Linpan of Western Sichuan, helping to improve the quality and characteristics of rural external and internal environments and create health-promoting environments. 相似文献
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中国柑橘生产空间变迁及其驱动因素 总被引：1，自引：0，他引：1
综合运用产业集中度、探索性数据分析（ESDA）、产业重心模型、空间杜宾模型等方法对中国柑橘生产空间演变特征,以及驱动因素进行实证分析。结果显示：1978－2015年中国柑橘生产空间呈现扩张态势,可分为急剧增长期（1978－1991年）、低速增长期（1992－2000年）、稳步增长期（2001－2015年）。中国柑橘生产空间主要集中在西南地区、中南地区、华东地区,具有“北冷南热”的空间结构。柑橘生产空间在省域尺度上具有显著的正向空间自相关特征,呈现显著的地理集聚现象,且集聚呈现先急剧下降,其后再波动上升的变化过程。自2000年起,生产空间重心持续性向西南向迁移,“西移南扩”的迁移趋势明显。中国柑橘生产空间从最初的自然驱动,逐步转向为“自然－社会”驱动。自然资源禀赋决定着中国柑橘生产的基础空间,社会经济因素是柑橘生产空间变迁的重要原因。在市场区位因素中,道路运输、水果消费对柑橘生产空间存在显著的正向效应,路网密度提高,提升了产区的经济区位,居民收入的提高扩大了柑橘消费需求,因此每提高1%,柑橘面积分别增加0.192%和0.107%。在生产要素中,劳动力投入、水利灌溉对柑橘生产空间存在正向效应,每提高1%,柑橘面积分别增加0.934%和0.094%。在社会经济因素中,非农就业机会引起的农村劳动力流失,对柑橘生产空间存在强烈的负向效应,每提高1%,柑橘面积减少1.365%。科技进步带来的新品种、新技术对柑橘生产空间存在正向效应,每提高1%,柑橘面积增加0.058%。人均粮食占有量的直接效应为负向效应,间接效应为正向效应,意味着在分配有限土地资源的博弈中,本地土地首先要满足粮食安全,因此抑制柑橘面积增加。而邻近地区人均粮食占有量的提高,通过粮食流通能够满足本地粮食安全,促进柑橘面积增加。 相似文献
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Dual factors of climate and human on the hydrological process are reflected not only in changes in the spatiotemporal distribution of water resource amounts but also in the various characteristics of river flow regimes. Isolating and quantifying their contributions to these hydrological alterations helps us to comprehensively understand the response mechanism and patterns of hydrological process to the two kinds of factors. Here we develop a general framework using hydrological model and 33 indicators to describe hydrological process and quantify the impact from climate and human. And we select the Upper Minjiang River(UMR) as a case to explore its feasibility. The results indicate that our approach successfully recognizes the characteristics of river flow regimes in different scenarios and quantitatively separates the climate and human contributions to multi-dimensional hydrological alterations. Among these indicators, 26 of 33 indicators decrease over the past half-century(1961–2012) in the UMR, with change rates ranging from 1.3% to 33.2%, and the human impacts are the dominant factor affecting hydrological processes, with an average relative contribution rate of 58.6%. Climate change causes an increase in most indicators, with an average relative contribution rate of 41.4%. Specifically, changes in precipitation and reservoir operation may play a considerable role in inducing these alterations. The findings in this study help us better understand the response mechanism of hydrological process under changing environment and is conducive to climate change adaptation, water resource planning and ecological construction. 相似文献
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Agricultural suitability maps are a key input for land use zoning and projections of cropland expansion. Suitability assessments typically consider edaphic conditions, climate, crop characteristics, and sometimes incorporate accessibility to transportation and market infrastructure. However, correct weighting among these disparate factors is challenging, given rapid development of new crop varieties, irrigation, and road networks, as well as changing global demand for agricultural commodities. Here, we compared three independent assessments of cropland suitability to spatial and temporal dynamics of agricultural expansion in the Brazilian state of Mato Grosso during 2001–2012. We found that areas of recent cropland expansion identified using satellite data were generally designated as low to moderate suitability for rainfed crop production. Our analysis highlighted the abrupt nature of suitability boundaries, rather than smooth gradients of agricultural potential, with little additional cropland expansion beyond the extent of the flattest areas (0–2% slope). Satellite-based estimates of the interannual variability in the use of existing crop areas also provided an alternate means to assess suitability. On average, cropland areas in the Cerrado biome had higher utilization (84%) than croplands in the Amazon region of northern Mato Grosso (74%). Areas of more recent expansion had lower utilization than croplands established before 2002, providing empirical evidence for lower suitability or alternative management strategies (e.g., pasture–soya rotations) for lands undergoing more recent land use transitions. This unplanted reserve constitutes a large area of potentially available cropland (PAC) without further expansion, within the management limits imposed for pest management and fallow cycles. Using two key constraints on future cropland expansion, slope and restrictions on further deforestation of Amazon or Cerrado vegetation, we found little available flat land for further legal expansion of crop production in Mato Grosso. Dynamics of cropland expansion from more than a decade of satellite observations indicated narrow ranges of suitability criteria, restricting PAC under current policy conditions, and emphasizing the advantages of field-scale information to assess suitability and utilization. 相似文献
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利用大邑、西岭雪山滑雪场及周边区域自动站2005～2017年每年10月～次年2月逐日最低温度资料，通过统计分析区域自动站与大邑站候平均最低温度差值，建立以大邑本站最低温度预报值为基础，加上逐候最低温度差值后得到区域各站的日最低温度预报的候最低温度差值订正方法；用距滑雪场最近的格点温度预报数据代替滑雪场站点温度预报，选出最低温度，以气温预报变化量，建立最低气温预报的模式温度订正方法；建立以候最低温度差值订正和模式温度订正进行加权平均的最低温度集成订正方法。通过对以上三种最低温度预报方法进行检验，发现最低温度集成订正方法预报准确率最高。基于最低温度集成订正方法预报西岭雪山滑雪场的最低温度，结合智能网格降水预报结果和降雪最低温度阈值判别，建立西岭雪山降雪的订正预报方法。 相似文献
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This paper aims at developing a methodology for assessing urban dynamics in urban catchments and the related impact on hydrology. Using a multi-temporal remote sensing supported hydrological modelling approach an improved simulation of runoff for urban areas is targeted. A time-series of five medium resolution urban masks and corresponding sub-pixel sealed surface proportions maps was generated from Landsat and SPOT imagery. The consistency of the urban mask and sealed surface proportion time-series was imposed through an urban change trajectory analysis. The physically based rainfall-runoff model WetSpa was successfully adapted for integration of remote sensing derived information of detailed urban land use and sealed surface characteristics.A first scenario compares the original land-use class based approach for hydrological parameterisation with a remote sensing sub-pixel based approach. A second scenario assesses the impact of urban growth on hydrology. Study area is the Tolka River basin in Dublin, Ireland.The grid-based approach of WetSpa enables an optimal use of the spatially distributed properties of remote sensing derived input.Though change trajectory analysis remains little used in urban studies it is shown to be of utmost importance in case of time series analysis. The analysis enabled to assign a rational trajectory to 99% of all pixels. The study showed that consistent remote sensing derived land-use maps are preferred over alternative sources (such as CORINE) to avoid over-estimation errors, interpretation inconsistencies and assure enough spatial detail for urban studies. Scenario 1 reveals that both the class and remote sensing sub-pixel based approaches are able to simulate discharges at the catchment outlet in an equally satisfactory way, but the sub-pixel approach yields considerably higher peak discharges. The result confirms the importance of detailed information on the sealed surface proportion for hydrological simulations in urbanised catchments. In addition a major advantage with respect to hydrological parameterisation using remote sensing is the fact that it is site- and period-specific. Regarding the assessment of the impact of urbanisation (scenario 2) the hydrological simulations revealed that the steady urban growth in the Tolka basin between 1988 and 2006 had a considerable impact on peak discharges. Additionally, the hydrological response is quicker as a result of urbanisation. Spatially distributed surface runoff maps identify the zones with high runoff production.It is evident that this type of information is important for urban water management and decision makers. The results of the remote sensing supported modelling approach do not only indicate increased volumes due to urbanisation, but also identifies the locations where the most relevant impacts took place. 相似文献
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水工隧洞高压固结灌浆的目的是加固隧洞围岩、封闭隧洞周边岩体裂隙,提高隧洞围岩的整体性和抗变形能力,增强围岩抗渗能力和长期渗透稳定性。主要介绍了引水隧洞在未进行混凝土衬砌的条件下实施高压防渗固结灌浆施工的试验及其成果,为该类洞段灌浆设计和施工提供依据。 相似文献
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This study employed Slack-based measure (SBM), Meta-frontier analysis, and Malmquist–Luenberger index (MLI) approaches to measure energy efficiency (EE), production technology heterogeneity, and energy productivity variation and its main determinants in developed and developing G20 countries for the period 1995–2020. The study's findings are: (i) Average EE for G20 countries is 0.8577, but still has an improvement potential of 14.23 percent. (ii) Developed countries have a higher average EE than developing (0.8927 > 0.8290). Results further revealed that energy efficiency scores in Argentina, Australia, Brazil, France, Saudi Arabia, South Africa, the US, the UK, and Korea are>1. (iii) Technology gap ratio (TGR) value in developed countries is higher than in developing (0.9869 > 0.6801), indicating that developed countries have advanced energy technologies superiority. The average MLI is less than one, showing a decline in energy productivity mainly due to a decline in technical efficiency, as EC < TC. (iv) Developed G20 countries get 0.64 percent aggregate growth in energy productivity as their MLI score is 1.0064, mainly due to technological growth (TC = 1.0161). Developing G20 countries, on the other hand, witnessed a decline in their energy productivity during 1995–2020, as MLI = 0.9925 > 1, designating that, on average, there is a 0.75 % decline in MLI. 相似文献
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采用短基线集时序干涉测量(small baseline subset InSAR,SBAS-InSAR)技术,利用多时相合成孔径雷达数据,对川西高山峡谷区开展地表多时相、长时序形变监测与地质灾害隐患早期识别研究。介绍了时序InSAR方法原理,梳理了数据处理流程,分析了小金川河流域雷达可视性,利用2018-11—2019-12共26期的Sentinel-1A历史存档数据开展了流域内地表形变监测,结果表明: 流域内雷达视线方向的年平均形变速率为-51.12~75.28 mm/a; 依据形变异常分布规律,共判译出4处形变异常区与11处潜在地质灾害隐患点,其中6处隐患点为已知地质灾害点,其余5处隐患点尚不为人知。以隐患点P1(阿娘寨滑坡)为典型案例,开展了长时序监测分析与验证,评估利用InSAR技术开展地质灾害隐患早期识别的可靠性,证明了SBAS-InSAR技术在地质灾害早期识别中的优势及有效性,其技术成果在川西高山峡谷区具有大范围推广应用的潜力。 相似文献