几种甘草（Glycyrrhiza）光合特性、形态特征及生物量比较

采用TPS-2型光合测定仪对乌拉尔甘草（Glycyrrhiza uralensis）、胀果甘草（G.inflata）、刺果甘草（G.pallidiflora）、光果甘草（G.glabra）和黄甘草（G.eurycarpa）栽培植株上部叶片光合日变化特征进行研究,对光合色素、形态和生物量进行测定和分析,并比较上述指标的种间差异,为甘草栽培技术和综合利用模式提供科学依据。结果表明：（1）各种的叶片净光合速率、蒸腾速率、水分利用率和气孔导度日变化均呈“双峰”型,峰值分别出现于12：00和16：00,14：00存在明显的光合“午休”现象;叶片细胞间隙CO₂浓度日变化均呈“W”型,峰值分别出现于08：00、14：00和18：00,低谷出现于12：00和16：00;叶片温度日变化均呈“倒V”型,峰值出现于14：00,低值出现于08：00和18：00;且各种上述指标存在不同程度的差异性。（2）各种的叶片叶绿素a、叶绿素b、类胡萝卜素含量及叶绿素总量和叶绿素a含量/叶绿素b含量大小各不相同,其中叶绿素a含量存在种间显著差异。（3）各种的主茎分枝数、叶片数、主茎高、主根长、地上部分干重、地下部分干重及总生物量存在一定的差异性。（4）净光合速率日均值与气孔导度、蒸腾速率、水分利用效率、叶面温度日均值和叶绿素a含量正相关,相关系数分别为0.984、0.977、0.927、0.909和0.933,与胞间CO₂浓度负相关,相关系数为-0.972。乌拉尔甘草具有较高的光合性能和经济产量,适于在该区大规模推广栽培;胀果甘草、光果甘草和刺果甘草总生物量较大,除地下部分药用外,应加强对其地上部分的开发利用;黄甘草光合性能、经济产量和总生物量均显著低于其他种,但地上部分鲜嫩,建议对其加强畜牧业方面的开发利用。     

Mindful Learning in Geography: Cultivating Balanced Attitudes Toward Regions

This study examines the potential of mindful learning in geography education. A hypothesis was developed to form the research topic, and three experiments were performed to analyze it. The experiments supported the hypothesis. In other words, mindful learning was found to be helpful for cultivating balanced attitudes toward regions. In conclusion, mindful learning has the potential to be a simple but helpful method of geography education.     

种植业可持续发展的支持系统——农作物卫星遥感估产

本文从种植业可持续发展需要出发,指出建立农作物卫星遥感估产系统是实现种植业可持续发展地面信息准确、快速、经济获取的最有效手段,并能成为种植业可持续发展的支持系统。本文还分析了我国种植业地面信息统计现状和卫星遥感估产国内外研究进展,一个实际运行的农作物卫星遥感估产系统可以监测作物长势、种植面积和作物产量,与其它信息相配合有利于种植业可持续发展战略的实施。     

气候变化影响下北海公园冰上运动季的特征与情景模拟

北海公园冰上运动是北京传统体育文化遗产的重要组成内容以及冬季休闲旅游的代表性符号,强化其气候变化影响与适应研究,对于应对全球变化的挑战、践行“大力发展冰雪经济”的指示具有重要意义。本文从多源文献中提取分析了其冰场多年启闭日期（间接指示冰层厚15 cm）的变化特征,并结合气温器测数据以及4种气候情景数据（SSP1-2.6、SSP2-4.5、SSP3-7.0和SSP5-8.5）,利用留一交叉验证法探讨了不同温度指标和拟合方程的预测效果差异,进而对未来冰上运动季的变化、潜在影响与适应对策进行分析。结果表明：① 1989—2018年冰上运动季始日、末日和持续长度的均值分别为1月1日、2月5日和36 d,对应的趋势表现为不显著的推迟（1.00 d/10a）、提前（-0.77 d/10a）和延长（1.11 d/10a）,时序变化可区分为1989—2000年、2001—2013年和2014—2018年3个阶段。② 冰上运动季始、末日分别对其日期前59 d的日最低温和前94 d的日最高温有较好响应,利用这两个指标和玻尔兹曼函数可更好预测冰上运动季变化。③ 2021—2099年冰上运动季始日、末日和持续长度的均值分别较1989—2018年晚1 d、早1 d和缩短2 d,3个指标变幅一致缩小,对应的0.14 d/10a、-0.21 d/10a和-0.34 d/10a的趋势均达到0.01的显著性水平。④ 未来79 a内冬季两大节庆中元旦冰上运动的适宜性要大于春节,其中春节的适宜性在4种气候情景下相差不大,而元旦的适宜性则在4种情景下有一定差别。⑤ 在相关预估结果上,BCC-CSM2-MR、CanESM-5和UKESM这3种区域气候模式并没有太大差异,而热岛效应影响尚待深入研究。⑥ 为了在气候变暖背景下促进体旅融合消费、保障冰上运动产业高质量发展,运营企业应采取强化游客安全保障、扩展旅游产品谱系、购买冰量保险等全方位主动适应措施,研究者应加强研究气候变化影响的复杂性、改进旅游流的预测效果,而管理部门应大力推动产业风险管理报告的编制,充分重视气候变化风险的动态评估。     

Arctic summer sea ice phenology including ponding from 1982 to 2017

Information on the Arctic sea ice climate indicators is crucial to business strategic planning and climate monitoring. Data on the evolvement of the Arctic sea ice and decadal trends of phenology factors during melt season are necessary for climate prediction under global warming. Previous studies on Arctic sea ice phenology did not involve melt ponds that dramatically lower the ice surface albedo and tremendously affect the process of sea ice surface melt. Temporal means and trends of the Arctic sea ice phenology from 1982 to 2017 were examined based on satellite-derived sea ice concentration and albedo measurements. Moreover, the timing of ice ponding and two periods corresponding to it were newly proposed as key stages in the melt season. Therefore, four timings, i.e., date of snow and ice surface melt onset (MO), date of pond onset (PO), date of sea ice opening (DOO), and date of sea ice retreat (DOR); and three durations, i.e., melt pond formation period (MPFP, i.e., MO–PO), melt pond extension period (MPEP, i.e., PO–DOR), and seasonal loss of ice period (SLIP, i.e., DOO–DOR), were used. PO ranged from late April in the peripheral seas to late June in the central Arctic Ocean in Bootstrap results, whereas the pan-Arctic was observed nearly 4 days later in NASA Team results. Significant negative trends were presented in the MPEP in the Hudson Bay, the Baffin Bay, the Greenland Sea, the Kara and Barents seas in both results, indicating that the Arctic sea ice undergoes a quick transition from ice to open water, thereby extending the melt season year to year. The high correlation coefficient between MO and PO, MPFP illustrated that MO predominates the process of pond formation.     

测绘专业高等专科毕业生动手能力的培养

从高等专科教育培养目标与毕业生的基本要求出发 ,阐述专科毕业生动手能力培养的重要性 ;介绍工程测量专业毕业生必经掌握的基本操作技能与动手能力培养的方法和途径 ,阐述指导教师应具备的条件等     

The decreasing spring frost risks during the flowering period for woody plants in temperate area of eastern China over past 50 years

The temperate monsoon area of China is an important agricultural region but late spring frosts have frequently caused significant damage to plants there. Based on phenological data derived from the Chinese Phenological Observation Network （CPON）, corresponding meteorological data from 12 study sites and phenological modeling, changes in flowering times of multiple woody plants and the frequency of frost occurrence were analyzed. Through these analyses, frost risk during the flowering period at each site was estimated. Results of these estimates suggested that first flowering dates （FFD） in the study area advanced significantly from 1963 to 2009 at an average rate of -1.52 days/decade in North-east China （P〈0.01） and -2.22 days/decade （P〈0.01） in North China. Over the same period, the number of frost days in spring decreased and the last frost days advanced across the study area. Considering both flowering phenology and occurrence of frost, the frost risk index, which measures the percentage of species exposed to frost during the flowering period in spring, exhibited a decreasing trend of -0.37% per decade （insignificant） in Northeast China and -1.80% per decade （P〈0.01） in North China, implying that frost risk has reduced over the past half century. These conclusions provide important information to agriculture and forest managers in devising frost protection schemes in the region.     

Remotely-sensed phenology of Italian forests: Going beyond the species

Remotely sensed observations of seasonal greenness dynamics represent a valuable tool for studying vegetation phenology at regional and ecosystem-level scales. We investigated the seasonal variability of forests in Italy, examining the different mechanisms of phenological response to biophysical drivers. For each point of the Italian National Forests Inventory, we processed a multitemporal profile of the MODIS Enhanced Vegetation Index. Then we applied a multivariate approach for the purpose of (i) classifying the Italian forests into phenological clusters (i.e. pheno-clusters), (ii) identifying the main phenological characteristics and the forest compositions of each pheno-cluster and (iii) exploring the role of climate and physiographic variables in the phenological timing of each cluster. Results identified four pheno-clusters, following a clear elevation gradient and a distinct separation along the Mediterranean-to-temperate climatic transition of Italy. The “High-elevation coniferous” and the “High elevation deciduous” resulted mainly affected by elevation, with the former characterized by low annual productivity and the latter by high seasonality. To the contrary, the “Low elevation deciduous” showed to be mostly associated to moderate climate conditions and a prolonged growing season. Finally, summer drought was the main driving variable for the “Mediterranean evergreen”, characterized by low seasonality. The discrimination of vegetation phenology types can provide valuable information useful as a baseline framework for further studies on forests ecosystem and for management strategies.     

地信产业卓越工程师培养模式探索

针对目前地理信息学科教育培养模式缺乏工程实践,人才可获得程度低,与地理信息产业高速发展不适应的现状,该文探索并提出高等院校应根据产业人才培养目标、专业知识体系需求,以及高校自身特色,适当调整学科布局和培养方案计划,制定卓越工程师培养模式,并提出培养模式可与地理信息企业人才的再教育与培训计划衔接,充分利用国内外企业、机构与其他高校的优势资源与成功经验,实现产学研用融合。以武汉大学为例,阐述面向地理信息产业的复合型卓越工程师培养模式、方案及实施。