A New Indicator for Global Food Security Assessment: Harvested Area Rather Than Cropland Area

Cropland area has long been used as a key indicator of food security.However,grain yield is not solely controlled by the area of the cropland.Therefore,we proposed a new indicator to assess food security.Results show that from 1992 to 2004,the global cropland area increased by 840200 km^(2)(99.4%),but the grain yield increased only by 310 million t(29.1%);and from 2004 to 2015,the cropland area decreased by 39000 km^(2)(4.64%),but the grain yield increased by 370 million t(70.84%).This result showed that grain yield was not linearly correlated with cropland area,and delimiting the threshold of cropland protection may not guarantee food security.Combined with further correlation analysis,we found that the increase in the global grain yield was more closely related to the harvested area(R^(2)=0.94),which indicated that the harvested area is a more scientific and accurate indicator than cropland area in terms of guaranteeing food security.Therefore,if governments want to ensure the food security,they should choose a new and more accurate indicator:harvested area rather than cropland area.

Re-delineating mountainous areas with three topographic parameters in Mainland Southeast Asia using ASTER global digital elevation model data

Tropical mountainous areas not only provide substantial carbon storage and play an important role in global biological diversity, but also provide basic livelihood for a large number of poor ethnic minorities. However, there is no unified and explicit definition for mountainous areas. The local elevation range(LER) is a crucial structural parameter for delineating mountainous areas. However, current LER products are limited by the subjective selection of an optimum statistical window or coarser spatial resolution of topographical data. In this study, we presented an approach using thresholds for three topographic parameters, elevation, slope, and LER, derived from the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM) to redelineate the vast mountainous areas of mainland Southeast Asia(MSEA). The mean change-point analysis method was applied to determine the optimum statistical window of the 1 arc second(approximately 30 m)-resolution GDEM LER. The results showed that: First, the optimum statistical window is 38 × 38 cell units(width × height) in a rectangular neighborhood, or an area of about 1.30 km^2 for calculating GDEM LER in MSEA. Second, the LER of more than 80% of the area ranges from 30 m to 499 m in MSEA. The LERs in the northern and northwestern MSEA are greater than their counterparts in the south and east. Third, the area of the re-delineated mountainous areas was 83.52 × 10~4 km^2, about 38.71% of the total area. Spatially, the mountainous areas are mainly distributed in the north and northeast of MSEA. The re-delineated 30-m resolution map of the mountainous areas will serve as a topographical dataset for monitoring mountainrelated land surface changes in MSEA. The parameter-modified mountain extraction procedure can be expanded to delineate global mountainous areas.

Impact of Global Warming on Water Resource in Arid Area of Northwest China

As the unprecedented global warming is under way, the glacier retreat is getting more and more serious. In the inland arid area of Northwest China, due to very scarce precipitation, where there is water, there are oases. And the glacier melt water amounts to 22 % of the total direct supply of the inland river water and is of crucial importance to the survival and development of the oases. In this paper, using both the observed data and the previous research achievements of the glaciers in the inland valley of Northwest China where the oasis depending on the glacier is the only location suitable for human living, the authors describe the glacier retreat trend over the past half century, focusing on discussing the possible impact of the glacier retreat on the melt water runoff that is almost the only water resource efficient to nourish the oases. The authors find that even with increasing amount of water from the glacier with global warming, the water shortage is getting more and more serious and the environment is under a degrading way due to the accelerating economical development. The water shortage is bound to be more serious if the glacier retreat keeps on, especially after the glacier melt water is over its top for the degradedglacier scale. So suggestions are stressed in the end that a new water-saving pattern should be adopted in the area for a sustainable development due to the warming-up induced continuous glacier retreat.

Response of Land Use Planning in Less Developed Areas to Economic Globalization

Under the background of economic globalization, the development mechanisms of various regions face potential deep transformation, and the effective participation of less developed areas in China in economic globalization is of great significance to the sustainable development of Chinese economy and society. In this study, we summarized the characteristics and influences of economic globalization from the aspects of industrial recombination and transfer, competition, economic relevance and development modes, and analysed the opportunities and challenges of land use in less developed areas brought by economic globalization. Afterwards, based on the major problems of land use planning management in the middle of Jiangsu Province, we put forward some suggestion including management of planning process, balanced development of ecology and economy, strengtheningn planing use zoning, spatial agglomeration and protecting cultural diversity to response to economic globalization.

Relationship between the Northern Hemisphere Sea Ice Area and Global Temperature by Multifractal Analysis

Changes in Arctic sea ice are an important fingerprint of natural and anthropogenic climate change. In general, fractal properties may be observed in the time series of the dynamics of complex systems. To study the relations among the Northern Hemisphere (NH) sea ice area, solar activity, global temperature, and Pacific Decadal Oscillation (PDO) index, we investigated changes in the fractal behavior of these time series by multifractal analysis and applying the wavelet coherence. The relationship between the solar activity: solar flux, sunspot number (SSN), and ultraviolet B (UV-B), and NH sea ice area was assessed based on changes in fractality. We identified the existing relations among the NH sea ice area, global temperature, and PDO based on changes in fractality and wavelet coherence. In the 2000s when the global warming hiatus occurred, after the order formation of NH sea ice area in the early 2000s, the change in state from multifractal to monofractal of the PDO and global temperature occurred, when fluctuations became large and multifractality became strong. We identified a small change in fractality for NH sea ice area, UV-B, and global temperature and a large change in fractality for solar flux, SSN, and PDO, which had large fluctuation. Our results will contribute to further studies on climate change.

Pressure level of maximum radiative heating enhancement in response to increasing CO_(2) over the global monsoon area

Based on the 1%CO_(2) experiment of CMIP6,in response to increasing CO_(2),the summer-mean radiative heating(RH)over the global monsoon area(MA)generally features an increasing response in the mid-troposphere and a decreasing response in the lower and upper troposphere.The pressure level of the maximum RH increase over the Asian MA is the highest and largest in range(500–775 hPa);the maximum increases over the North African,South American,and Australian MA are at 550–600 hPa;throughout the North American MA,the maximum heating increase is at 600 hPa;and the levels of the maximum over South Africa are 600 and 775 hPa.For most of the global MA,the maximum enhancement of RH is at 500,550,and 600 hPa.It is mainly led by the increase in cloud water at and above the maximum level and the decrease in cloud water below,which leads to similar changes in total cloud mass.Because of the longwave heating(cooling)effect at the cloud base(top),the RH enhancements peak at those levels.For the northeast part of the Asian MA and southeast part of the South African MA,RH enhancement peaks at 700 and 775 hPa,mainly attributable to the cloud water reduction below.The reduction leads to similar changes in total cloud.Due to the longwave cooling effect at the cloud top,the reduction contributes to the RH enhancement at the corresponding maximum levels.

全球海洋中心城市的湾区实践——以粤港澳大湾区为例

粤港澳大湾区是加快实施海洋强国战略的重要支点,全球海洋中心城市建设则是进一步推动粤港澳大湾区建设的关键抓手。全球海洋中心城市作为当前海洋城市建设与评价最具影响力的目标对象,需要分别在全球与湾区视角下考察粤港澳大湾区的优势与挑战。本研究通过解读全球海洋中心城市的概念与内涵,剖析了典型全球海洋中心城市的显著特征,以及与国际一流湾区发展的关系。研究发现,粤港澳大湾区在全球海洋中心城市数量和航运物流方面具有优势,但是在海事技术、竞争力与吸引力等方面面临巨大的竞争挑战。粤港澳大湾区推进全球海洋中心城市建设,着重要加快提升国际航运能力、加强海洋科技创新、参与全球海洋治理、强化海洋战略规划等。

3种营养筛查工具在骨与软组织肿瘤患者营养不良风险评估中的临床价值

目的:调查骨与软组织肿瘤患者营养不良风险的发生情况,探索营养风险筛查2002(NRS2002)、通用筛查工具(MUST)、患者主观整体评估简表(PG-SGASF)等3种营养筛查工具在骨与软组织肿瘤患者营养不良风险评估中的临床价值。方法:对山西省肿瘤医院骨与软组织科2023年8月—2024年5月的所有入院成年患者进行问卷调查,调查内容包括:患者一般情况(年龄、性别、身高、体重);患者体重在近2周、1个月、2个月、3个月、6个月的变化情况;饮食改变情况以及影响饮食的原因等。整理完成NRS2002、MUST、PG-SGASF得分。结合患者临床资料疾病诊断、治疗情况进行统计分析。率的比较采用卡方检验,定量资料两组比较采用Mann-Whitney检验,多组比较采用Kruskal-WallisH检验,绘制韦恩图、ROC曲线。结果:合格问卷633份,男性327例、女性306例,平均年龄(54.41±14.35)岁。骨与软组织肿瘤患者营养不良风险在14%~22%之间,恶性肿瘤患者营养不良风险发生率更高。3种筛查结果绘制韦恩图显示,NRS2002与MUST一致性更高。以NRS2002为基础绘制ROC曲线(曲线下面积:MUST:0.9287,PG-SGASF:0.596)。结论:骨与软组织肿瘤患者营养不良风险发生率较其他类型肿瘤患者偏低,但恶性度越高营养不良风险越大。NRS2002有一定的漏诊情况,MUST简易且全面,PG-SGASF更适合用于评估。

南水北调中线受水区水资源利用效率及影响因素

为提升南水北调中线工程受水区水资源利用效率,以工程沿线北京、天津2个直辖市和河南、河北18个省辖市共计20个地域单元为研究区域,基于2015—2021年面板数据,采用Super-SBM模型、GML模型及sys-GMM估计法对受水区水资源利用效率进行测度,对影响因素进行识别。结果表明:全区水资源静态利用效率总体偏低但呈波动上升态势,区域差异较大,呈京津板块>河南板块>河北板块格局,空间上呈现以京津冀、郑州2个都市圈为核心向外围逐渐递减的“核心-外围”结构;全区水资源动态利用效率整体呈波动上升趋势,主要源于技术进步,而技术效率作用有限;经济发展水平、水资源禀赋、科技水平、城镇化进程、人口密度与水资源利用效率显著正相关,水污染程度、产业结构、环境规制与水资源利用效率显著负相关。

地理空间数据等积全球格网多模式三维扩展方法

全球离散格网系统是新型地理空间数据组织框架,等面积格网由于在采样和空间分析方面的独特优势而备受关注,但相关研究囿于地球表面,缺乏扩展至三维广域空间的一般方法。本文首先提出将等积球面格网系统扩展为球体格网系统的多种剖分模式,并实现其统一数学描述和详细数学证明;然后引入体积和紧致度指标定量评价不同剖分模式的体元性质,并与球体退化八叉树格网(SDOG)、大圆弧八叉树格网(SGOG)作对比;最后初步探索了本文方法的应用案例,讨论了不同应用需求下选择剖分模式的原则。对比试验结果表明,退化剖分的体元各项指标均优于规则剖分,等体积和退化剖分的体积性质优于SDOG,紧致度性质优于SGOG。本文多剖分模式三维扩展方法不仅符合国际标准等体积的要求,而且兼顾常规剖分设计选项,为不同应用需求提供了参考依据。

腹膜透析患者主观综合性营养评估(SGA)的临床研究

目的：观察主观综合性营养评估（ Ｓ Ｇ Ａ） 对持续不卧床腹膜透析（ Ｃ Ａ Ｐ Ｄ） 患者营养状态的评估价值。方法：对２３ 例 Ｃ Ａ Ｐ Ｄ患者进行 Ｓ Ｇ Ａ，并对其中１７ 例接受饮食强化治疗的患者进行了６ 个月前瞻性观察。结果：２３ 例患者中营养良好１２ 例（５２ ．２ ％ ） ，轻至中度营养不良９ 例（３９ ．１ ％ ） ，严重营养不良２ 例（８ ．７ ％ ） 。 Ｔ Ｐ、 Ａｌｂ 、 Ｈｂ 、 Ｂ Ｕ Ｎ、 Ｔ Ｇ、 Ｃｈ 及 Ｋ Ｔ／ Ｖ、ｎ Ｐ Ｃ Ｒ、ｒ Ｃｃｒ 以及蛋白质和热量摄入等客观检查指标在 Ｓ Ｇ Ａ 评估为营养良好与营养不良两组之间差异显著，有统计学意义；１７ 例饮食强化治疗后体重、上臂肌围及 Ｔ Ｐ、 Ａｌｂ 、 Ｔ Ｇ、 Ｂ Ｕ Ｎ、 Ｈｂ 等显著增加（ 均有统计学意义） ， Ｓ Ｇ Ａ 评估结果与各项客观指标之间的相关系数均在０ ．９０以上，具有显著的统计学意义。结论： Ｓ Ｇ Ａ 营养评估法能准确反映腹膜透析患者的营养状态，是一种较为理想的评估方法。

胃癌患者术前PG-SGA评分与人体成分的相关性

目的探讨胃癌患者术前主观整体评估(PG-SGA)评分与人体成分的相关性。方法选择天津市第三中心医院2015年6月至2016年10月收治的82例胃癌患者为研究对象,均进行PG-SGA量表评估及人体成分测定,PG-SGA量表得分为0~3分者纳入营养良好组(n=25),4分以上者纳入营养不良组(n=57)。比较两组患者人体成分指标,以及PG-SGA评分与人体成分指标的相关性。结果营养不良组患者的体质量、体质量指数(BMI)、体脂肪量、体脂百分比、瘦体组织、身体水分含量、细胞外液量分别为(51.92±6.85)kg、(18.58±1.92)kg/m2、(13.32±3.15)kg、(14.19±4.05)%、(44.13±4.96)kg、(33.02±2.64)L、(12.27±1.38)L,均明显低于营养良好组的(62.95±11.32)kg、(23.45±1.86)kg/m2、(15.87±3.32)kg、(23.37±3.31)%、(47.18±5.23)kg、(34.75±3.21)L、(13.72±1.37)L,差异均有统计学意义(P<0.05);PG-SGA评分与体质量、BMI、体脂肪量、体脂百分比、蛋白质含量、瘦体组织、体细胞量、骨骼肌量、身体水分含量、细胞外液、细胞内液均呈负相关性(P<0.05)。结论 PG-SGA与人体成分指标具有较好的相关性,术前进行PG-SGA评分及人体成分测定对评估胃癌患者的营养状况和营养干预方案的制定具有重要的临床意义。

系统化全域建设背景下平原河网地区海绵城市监测体系构建

在系统化全域海绵城市建设背景下,为支撑平原河网地区海绵城市建设成效评价,应建立以典型片区为核心的系统化全域监测体系。针对平原河网地区排水系统特征与海绵城市监测难点,研究了根据空间布局、下垫面特征、地形、水系特征、海绵城市建设情况等因素确定典型片区数量、位置、边界等关键信息的方法,提出了片区内“本底特征、源头减排、过程控制和系统治理”系统化监测体系的构建方法。以宿迁市为例,介绍了海绵城市建设概况、典型片区选取方案与依据,并制定了2个典型片区系统化监测体系的构建方案,该方案有效支撑了宿迁市各层级海绵城市建设成效评价。

全球智慧城市群的比较研究

对全球智慧城市群或城市带的发展状况开展比较研究,分析其发展水平。首先,展示针对全球智慧城市群的相应评价方法,构建包括传统基础设施、数字基础设施和制度基础设施领域在内的9个指标。其次,以长三角地区、粤港澳大湾区、纽约湾区、大湖区、日本三湾、波斯湾、墨西哥湾、北海和波罗的海在内的滨海城市群或城市带,以及阿尔卑斯山脉、喀尔巴阡山—巴尔干山脉、落基山脉和亚洲内陆在内的内陆集群作为分析对象。最后,对上述城市群或城市带的智慧城市建设情况开展比较研究,展示它们不同的发展水平。结果显示,纽约湾、波罗的海和北海智慧城市群或城市带领先全球,令人意外的是粤港澳大湾区和长三角智慧城市群在总分和单项上均与全球有一定差距。

基于MaxEnt的松墨天牛在中国的潜在分布及其对气候变化的响应

由于世界气候变暖而导致的害虫空间分布格局的巨大变化,增加了害虫预防难度。通过MaxEnt模型,结合GIS方法,模拟松墨天牛在中国的潜在分布区,预测、对比、分析松墨天牛在未来3种气候情景(RCP2.6、RCP4.5和RCP8.5)下分布范围和空间布局,及其中心节点移动的规律。结果表明:所有AUC值均超过0.95,准确性也处于“极好”的状态。在当前气候环境下,松墨天牛在中国的适生区范围为90°~125°E,20°~41°N,由西向东呈连续分布,集中分布于我国东南部;在未来气候条件下,中适生区面积减少,低适生区、高适生区面积增加,并向高纬度、高海拔地区扩散,RCP8.5扩散范围最大。适生区中心点向西北、东北方向迁移,迁移趋势在高浓度排放情景下(RCP 8.5)响应最为剧烈。为松墨天牛的合理区划提供了有效手段,为应对气候变暖提供了理论依据。

Using satellite-derived land surface temperatures to clarify the spatiotemporal warming trends of the Alborz Mountains in northern Iran

The Alborz Mountains are some of the highest in Iran,and they play an important role in controlling the climate of the country’s northern regions.The land surface temperature(LST)is an important variable that affects the ecosystem of this area.This study investigated the spatiotemporal changes and trends of the nighttime LST in the western region of the Central Alborz Mountains at elevations of 1500-4000 m above sea level.MODIS data were extracted for the period of 2000-2021,and the Mann-Kendall nonparametric test was applied to evaluating the changes in the LST.The results indicated a significant increasing trend for the monthly average LST in May-August along the southern aspect.Both the northern and southern aspects showed decreasing trends for the monthly average LST in October,November,and March and an increasing trend in other months.At all elevations,the average decadal change in the monthly average LST was more severe along the southern aspect(0.60°C)than along the northern aspect(0.37°C).The LST difference between the northern and southern aspects decreased in the cold months but increased in the hot months.At the same elevation,the difference in the lapse rate between the northern and southern aspects was greater in the hot months than in the cold months.With increasing elevation,the lapse rate between the northern and southern aspects disappeared.Climate change was concluded to greatly decrease the difference in LST at different elevations for April-July.

基于改进YOLOv7模型的血细胞检测算法研究

在医学上,血细胞计数检测是衡量人体健康与否的重要诊断方法,但是血细胞图像中存在小目标和重叠目标的检测难点。针对上述问题,提出一种改进的YOLOv7目标检测算法。通过对原始的YOLOv7网络增加全局注意力机制(GAM),提升网络的感受野,提高对小目标的检测精度;提出融合了加权双向特征金字塔网络(BiFPN)和递归门控卷积HorNet的特征金字塔HorNet-BiFPN结构,利用其高阶空间交互作用增强网络的特征融合能力,实现对红细胞重叠区域的建模,解决对重叠红细胞的检测问题。实验结果表明,改进的YOLOv7模型的检测精确率达到了96.3%,对单张图片的检测时间达到了74 ms,对图像中的3类细胞均实现了较强的检测效果,达到了医学辅助诊断的合理性。

Analysis and prediction of glacier evolution trend(2020-2100)in Northern Xinjiang

Glaciers,as“solid reservoirs”,are precious resources in arid areas.The study of glaciers is of great significance to the sustainable development and management of agriculture and the economy in northern Xinjiang.The area of glacier distribution on the 1963 topographic map data,1975 MSS data,2000 ETM data,2008 CBERS-2 data,2014 and 2018 ETM+were collected as secondary data.According to the remote sensing survey,the glacier areas in Northern Xinjiang are identified during 1963-2018.Based on the evolution of glacier area in the past 55 years,and using two scenarios,the average annual decrease area of a region during the whole 1963-2018 and the period with the minimum reduction area,the glacier areas of Southern Tianshan Mountains,Western Tianshan Mountains,Eastern Tianshan Mountains,the Sawuer Mountains and Altai Mountains in Northern Xinjiang,and the whole northern Xinjiang in 2030,2040,2050,and 2100 are examined and predicted.In 2100,the glacier area in Northern Xinjiang may decrease by 43%-59%.

新常态下超大型城市干线路网发展思路——以深圳市为例

新常态下,经济增速放缓,传统发展方式难以为继,需要创新动力机制,加强供给侧改革。城市干线路网作为支撑城市空间结构优化调整的主动脉,新阶段,理应聚焦城市发展新趋势,从“高速度增长”向“高质量发展”转变。本文剖析当前深圳干线路网存在的问题,研判未来发展态势,提出未来深圳干线路网应该实现“四大升级”,引导人口、用地、建筑结构同步优化升级,促进区域供给侧的生产要素合理和有序流动,提高资源配置效率和质量,促进区域产业升级和经济发展。

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中中新世气候适宜期是新生代全球降温趋势下一次强烈的全球升温事件,其气候状态被认为是未来全球变暖最可能达到的状态。亚洲内陆干旱区是全球典型的中纬度干旱区,其干旱化过程对人类生存环境影响最为深刻、最为直接。在全球变暖背景下,叠加人类活动的影响,干旱区变得更加脆弱,其扩张或变迁都会直接影响人类的生存和可持续发展。探讨亚洲内陆干旱区在中中新世全球气候变暖背景下的气候演化历史,对未来气候变暖模式下干旱区的气候变化预估提供重要参考。本文梳理了亚洲内陆干旱区典型盆地现有中中新世期间古气候演化研究结果,通过环境磁学参数、孢粉、同位素等多种气候代用指标的综合分析,发现在中中新世期间,多数地区呈现湿润化,但开始的时间有所差异,同时,少量地区呈现持续干旱化的现象。另一方面,对中中新世适宜期形成的主控因素依然存在较大争议,有的学者认为哥伦比亚玄武岩喷发是主要因素,有的学者认为构造活动是主要因素。要解决上述争议,需要获取更多具有精确年代控制的高分辨率记录,以确定中中新世升温事件的起始响应时间。通过正确解译气候代用指标,特别是对古气候变化响应最为直接和敏感的孢粉,以及环境磁学参数和地球化学比值等蕴含的古环境信息,厘清各种因素对气候变化造成的影响,揭示亚洲内陆干旱区中中新世气候适宜期气候演化的驱动机制。