中国桃金娘的地理分布及气候限制性因子分析

桃金娘是我国热带地区优良的林木种质资源,具有重要的食用、药用、生态和观赏价值。全面了解桃金娘在中国的地理分布现状,对该物种的引种与资源开发具有重要意义。为了解桃金娘在中国的地理分布格局和影响其分布的关键性气候因子,本研究通过植物标本数据库记录、文献记载及实地调查获取的地理坐标,对其水平地理分布和垂直分布进行地理分布格局分析。同时基于不同分布点的19个生物气候数据,利用主成分分析法分析了影响桃金娘地理分布的限制性因子。结果表明,桃金娘在中国水平地理分布以热带-南亚热带为主,过渡至中亚热带,东部地区的最北分布点位于浙江的平阳。桃金娘垂直分布多集中在海拔500 m以下的低山丘陵区,体现出桃金娘喜温热而不耐寒冷的特性。主成分分析的结果表明,PC1~PC3主成分的贡献率分别为41.23%、22.44%和16.34%,累计贡献率达80.02%(>75%);因此影响桃金娘地理分布的主要信息集中在前3个主成分。主成分1表明温度是限制桃金娘往北及高海拔分布的最关键性因子,尤其是最冷季均温和极端最低温。各生物气候因子对桃金娘分布限制的重要性排序依次为:最冷季均温(Bio11)>极端最低温(Bio6)>年均温(Bio1)>最干季均温(Bio9)>年降水量(Bio12)>最湿月降水量(Bio13)>最湿季降水量(Bio16)>最暖季降水量(Bio18)。桃金娘的适宜分布区以最冷季均温为10℃和极端最低温为4℃以上的区域为佳,影响桃金娘在中国地理分布格局的关键性气候因子是1月的低温。水分因子是反映桃金娘喜欢温暖湿润的气候特点,并非是限制其地理分布的关键性因素。     

我国见血封喉适生区的气候特征分析

见血封喉具有重要的药用价值和使用价值,是我国热带季节性雨林的主要树种之一。了解见血封喉的适生区的气候因子情况,有利于其资源的保护和开发利用。本研究基于生态位模型理论对我国见血封喉地理分布区气候因子进行分析。以见血封喉在国内的现有天然地理分布数据为基础,通过DIVA-GIS获得见血封喉地理分布区气候因子;以分布样地内的海拔和气候数据20个指标进行主成分分析,结果获得4个主成分,其方差总贡献率为93.7%,其中第1主成分为海拔、降雨量和温度的综合因子;第2主成分为主要与低温有关的因子;第3主成分为主要与降雨量相关的因子;第4主成分为主要与极端温度相关的因子,其方差贡献率分别为42.9%、31.3%、13.0%和6.5%。以最大熵模型理论对见血封喉建立在我国适生区预测模型,预测的模型经ROC验证,模型的训练AUC为0.990,数据检验显示所建立的模型优良,预测精度高;刀切法检验结果表明,年平均气温bio1为影响见血封喉地理分布区气候影响分布的最关键生物气候因子,其次为平均日较差bio2。见血封喉在我国的适生区为广东、广西、海南、云南、台湾。最适生区面积最大的是广东,其次为广西,第三是海南;而高适生区和一般适合区主要是广西;云南和台湾为低适区。     

中国热带亚热带油梨生态适宜性区划

以瓜达拉哈拉(墨西哥)、危地马拉城(危地马拉)和拿骚(巴哈马)分别作为墨西哥系、危地马拉系和西印度系的原产地(参照点),国内极端低温平均值为≥-5℃、≥-3℃和≥0℃的各点分别作为三系的引种地(基本点),并选取了与油梨生长发育密切相关的年均温、平均日较差、极端最低温、年降水量以及热量与水分在年内的分配等28个气候因子作为区划指标,采用多元统计学中的主成分分析法和相似分析法,通过上机运算获得了各指标的权重系数和国内各点与原产地综合相似系数,用以表示两地之间的农业气候相似程度和作为生态适宜性区划的理论依据。结果表明,区划与实际吻合,具有较好的生物意义和指导意义。     

香水椰子裂果率与气候因子的通径分析

2007～2010年对香水椰子果实大小与裂果率进行观测后,对其裂果率与气候因子的相关和通径分析,结果表明:香水椰子的裂果率与各气候因子之间有一定的相关性,其中,月均温与裂果率之间呈极显著负相关(p0.01),月均温对裂果率的直接影响最大,月降雨天数次之;月极端最低温与裂果率之间呈显著负相关(p0.05),其对裂果率的间接影响最大。结果还表明,同一气候因子对不同果围椰果的裂果率的直接影响也不同。     

云南河口1953年植胶以来气候变化与橡胶树寒害初步分析

通过对云南河口县气象站1956～2010年共55年的气象资料,以年均温、降雨量、年极端最高温及极端最低温为指标,初步分析了河口地区55年来气候变化趋势和特点。结果显示：年均温以每年0.026 9℃的速度逐渐升高;年极端最高温以每年0.021 9℃的速度及年极端最低温也以每年0.041 7℃的速度在逐年上升;云南河口地区气候变暧趋势明显,虽然橡胶树寒害次数有所下降,尤其是从20世纪90年代以后,但受害频率和严重程度与气候变暖没有明显的相关性。     

大理地区马铃薯种植区划及发展方向探讨

<正> 一、概况大理市位于缜西低纬高原地带,具有冬干夏湿、四季如春、冬暖夏凉的温凉气候特点.最冷为1月份,月平均气温8.7℃;最热为7月份,平均气温20.1℃;年平均气温15.1℃;历年极端最高温低于36℃;极端最低温高于-4℃.光照强,光质好,全年日照时数为2274.7小时.年降雨量为1078.9毫米.土壤熟化程度高,耕层深,结构良好,有机质含量高,pH值为6左右,为发展四季马铃薯生产,提供了得天独厚的自然条件.     

贵州茶园建园技术及行业存在的问题

正贵州属中亚热带季风湿润气候,光热水资源丰富,生长季节长,在海拔185～800m的地区年平均气温15～20℃,最冷月均温5℃以上,最热月均温在22～25℃,日均温≥10℃,平均年积温5000℃以上,年降雨量1100～1 300mm。雨季常在4月中下旬开始,5～10月降水最多,占全年降水量的60～75%,雨热同季。在湿润的生物气候条件下,酸性黄壤广泛发育,宜茶酸性土壤约有66.7万公顷以     

山地茶园建设实践与体会——以晴隆茶园建设为例

<正>晴隆位于贵州省西南部黔西南州的北端,地处云贵高原向广西台斜过渡地带,属亚热带湿润季风气候,由于受昆明"准禁止锋"气候影响和北盘江几大支流水系强烈切割,形成了山高、谷深、坡陡,地势复杂,地形破碎,水土流失极为严重,气候变化无常,素有"十里不同天.下雨如过冬和阴雨成天遍地云"气候特征。据多年气象资料统计:最热7月份月平均温度20.8~22.6℃,极端最高温35℃,最冷月1月份月平均温度8~10℃,极端最低温-5℃,年有效积温4500~5000℃,无霜期     

云斑斜线天蛾在我国的适生性及限制性环境因子分析

云斑斜线天蛾是一种为害抗风桐的迁飞性昆虫,在我国西沙群岛多个岛屿发生。阐明云斑斜线天蛾在我国的适生区分布及其主要限制环境因子,可为该害虫扩散预警与防控提供理论依据。本文利用MaxEnt模型对云斑斜线天蛾在我国的潜在适生区进行预测,通过调整调控倍频和特征组合参数建立最优模型,使用刀切法及环境变量响应曲线对影响云斑斜线天蛾分布的环境因子进行评估。结果表明：云斑斜线天蛾在我国的潜在适生区位于海南、台湾、广东、广西、云南、贵州、湖南、江西、福建、浙江、安徽、湖北、四川、重庆、西藏;最冷月最低温（bio06）、昼夜温差月均值（bio02）、最暖季降水量（bio18）是影响云斑斜线天蛾潜在地理分布的主导环境因子。云斑斜线天蛾在我国南海诸岛具有较高危险性,建议建立监测预警与防控系统,将该害虫控制在合理水平。     

1971-2017年陇中地区气候变化及其对旱地春小麦产量的影响

为了解不同生育阶段气候变化对旱地春小麦产量的影响,利用陇中地区1971-2017年逐日气温和降水量,运用APSIM模型模拟春小麦生育期和产量,对近47年来该地区气候变化特征及其与春小麦产量的相关性进行了分析。结果表明,陇中地区年降水量按4.639 mm·10a^-1的速率显著减少,春小麦全生育期降水量按1.304 mm·10a^-1的速率减少,8个生育阶段的降水变化趋势不同,其中灌浆-成熟期的降水量下降幅度最大,倾向率为-2.995 mm·10a^-1;分蘖-拔节期的降水量有明显的上升趋势,倾向率1.855 mm·10a^-1。旱地春小麦全生育期和各生育阶段的日均温、日均最高温和日均最低温都呈上升趋势,并且日均最低温的上升幅度要大于日均最高温。经相关分析,旱地春小麦全生育期降水量和日均最高温与产量分别呈极显著和显著相关;拔节-孕穗期和灌浆-成熟期降水量与产量的相关性分别达显著和极显著水平,拔节-孕穗期和灌浆-成熟期日均温与产量均呈极显著相关,拔节-孕穗期和灌浆-成熟期的日均最高温与产量分别呈显著相关和极显著相关。     

气候变化下红茴砂在中国潜在适生区的最大熵生态位模型预测

红茴砂是姜科茴香砂仁属多年生草本植物,我国仅在海南地区有自然分布,是具有很高药用价值的濒危植物。为了解红茴砂在未来气候变化下的潜在适生区及其主要环境影响因子,以期对红茴砂的保育提供科学指导,将45条红茴砂分布位点数据与20个环境因子相结合,运用最大熵生态位模型MaxEnt和ArcGIS软件模拟了当前气候和未来2050年RCP2.6和RCP8.5两种不同气候条件下红茴砂在中国的潜在分布区,并分析影响红茴砂分布的主导环境因子。结果表明：当前气候条件下,红茴砂适生区总范围在18°~32° N、27°~122° E,面积约为1.24×10⁶ km²,主要集中分布在海南、贵州、福建、广东、广西、云南等地;影响红茴砂地理分布的主导环境因子为最湿月降水量、最暖季度降水量、年均温度变化范围、最冷月份最低温、海拔和最热季度均温,累计贡献率达87%;在未来2050年RCP2.6和RCP8.5两种不同气候情景下,红茴砂适生区域丧失面积均达到95%以上,潜在分布区缩小到云南、四川、西藏、贵州和台湾这5个省区,新增区域主要在西藏东南部和四川中南部,同时潜在总适生区和高适生区的质心有向西北方迁移的趋势。     

基于MaxEnt模型的可可潜在适宜分布研究

根据野外采样和文献查阅,系统整理了可可的地理分布记录,并利用MaxEnt生态位模型和ArcGIS软件对可可的潜在适宜分布范围进行预测。结果表明:北美洲南部、中南美洲北部、非洲西部、亚洲东南部以及太平洋美拉尼西亚群岛地区均是可可的潜在适宜分布区域。其中,中国海南、台湾南部、云南西双版纳、广东雷州半岛也属于可可的适生范围。经ROC(Receiver operating characteristic)曲线分析法验证,MaxEnt模型的AUC(Area under curve)值为0.977,表明预测结果具有较高的可信度。各环境变量重要性的Jacknife检验表明,极端最低温度、年降雨量、年温度变化范围、最暖季降雨量对可可的潜在分布影响最大。     

Density,Demography, and Influential Environmental Factors on Overwintering Populations of Sogatella furcifera (Hemiptera: Delphacidae) in Southern Yunnan,China

Sogatella furcifera (Horváth) (Hemiptera: Delphacidae) is the most serious pest on rice in southwestern China. Yunnan province is within this region and is a major overwintering area for S. furcifera in China. This field study was carried out over 4 yr (2010–2013) and focused on S. furcifera distribution, population density, and demography, as well as the relationship between various environmental factors and the distribution and density of overwintering S. furcifera in Yunnan. Our study demonstrated that overwintering populations of S. furcifera mainly occurred in valleys and lowlands below 25.02°N and 1,680 m above sea level (a.s.l.), where ratooning rice was present. The overwintering range of S. furcifera has expanded in Yunnan compared with 20 yr ago, and regional climate change is believed to be the main contributing cause for this expansion. Environmental factor analysis showed that the mean air temperature of the coldest quarter and precipitation of the coldest quarter were two key factors that were strongly linked to the overwintering distribution and density of S. furcifera in Yunnan. Wintertime temperature was the principal influencing factor to determine the distribution and density of S. furcifera, while the effect of precipitation was indirect in that it influenced the insect’s distribution via its host. This study documented the major overwintering areas of S. furcifera in Yunnan, which can be used to predict outbreak potential in the following spring. Hence, key climatic factors, overwintering distribution, and density of S. furcifera should be used when forecasting outbreaks in spring.     

Projecting Distribution of the Overwintering Population of Sogatella furcifera (Hemiptera: Delphacidae), in Yunnan,China With Analysis on Key Influencing Climatic Factors

Sogatella furcifera (Horváth) is the most threatening migratory rice pest in Yunnan, China. S. furcifera overwinters in low- altitude basins and valleys in southern Yunnan and migrates northward in spring and summer of the following year, causing serious damage during migration. The overwintering distribution, areas, and spatial pattern of S. furcifera are relevant to the migration and outbreak of this pest. Based on a 4-yr field survey (2010–2013), this study projected areas suitable for S. furcifera to overwinter using a species distribution model, and analyzed the key influencing climatic factors using principal component analysis (PCA) and ecological niche factor analysis (ENFA). Our field survey showed that the northern latitudinal- and upper elevation limits of overwintering S. furcifera was 25.4° N and 1,608 m in western Yunnan and 24.2° N and 1,563 m in eastern Yunnan. The species distribution model produced a fragmented distribution pattern, with most of which in western Yunnan and only a few in eastern Yunnan. The PCA and ENFA analyses showed that the mean temperature of the driest quarter and the precipitation of the coldest quarter significantly influenced the distribution of S. furcifera in winter. The results suggested that the complex topography, spatial differences in winter temperatures, and host availability altogether determined the distribution of overwintering S. furcifera . Compared with previous surveys, the northern latitudinal- and upper elevation limits of overwintering S. furcifera were higher, while the population became rarer in some suitable areas due to change of farmland utilization in winter and possibly climate change.     

The herbage productivity of tall fescue in the Pampas region of Argentina is correlated to its ecological niche

Since its introduction in the 1950s, tall fescue has spread throughout the Pampas region of Argentina to become naturalized in much of this region. Its annual forage mass productivity shows significant differences among sites. In this work, we hypothesized that, under dryland conditions, the annual forage mass productivity is related to the probability that the corresponding site is within the ecological niche of the species. To test this hypothesis, the spontaneous occurrence of tall fescue was surveyed in an area of 440 000 km². The abundance of tall fescue was verified on roadsides of national and provincial roads, in systematic sampling points spaced every 50 km. Subsequently, the ecological niche of the species was estimated with the Maxent software, based on the environmental information available. Additionally, the bioclimatic variables with greatest influence in determining the ecological niche were identified. Based on the information of comparative yield trials of tall fescue cultivars, a correlation analysis between annual forage mass productivity and the likelihood of ecological niche was performed. We found that the realized ecological niche of tall fescue in the Pampas region covers an area of 237 000 km² where the average minimum temperature of the coldest month is between 2·6 and 3·2°C and the rainfall in the driest quarter is 100 mm or higher. We also found that there were significant correlations between annual forage mass productivity and the probability of realized ecological niche. Therefore, in areas with low probability of realized ecological niche, other forage species could be a better option than tall fescue to obtain a high and stable annual forage mass productivity.     

Assessment and validation of CLIGEN-simulated rainfall data for Northern Taiwan

By using CLIGEN and long-term meteorological data, consecutive daily rainfall data can be simulated. At present, the applicability of CLIGEN to regions other than the United States remains to be tested. In this study, CLIGEN was first applied in a subtropical monsoon climate region. Rainfall data from 1961 to 1990 at three weather stations in northern Taiwan were collected, and rainfall parameters and patterns were validated. The results showed no significant difference in the mean and distribution patterns between observed and simulated values for rainfall parameters including precipitation for each month, wet days for each month, precipitation on wet days for each month and standard deviation of daily precipitation for each month. Regarding rainfall pattern, after re-calibration of storm pattern coefficients, the accuracy of the simulated storm duration was greatly enhanced. However, the simulated daily maximum 5- and 30-min peak intensities were overestimated, and there is room for improvement.     

濉溪县夏玉米生产与气象因子关系分析

利用濉溪1980～2006年夏玉米单产和同期气象资料进行统计分析,同时分析6月中旬至9月下旬光、热、水资源的分布特点及其对夏玉米生产发育的影响。结果表明:濉溪夏玉米的气象波动指数为0.105 3,占夏玉米产量波动的37.9%;7月中下旬的平均气温、8月下旬的降水、8月中下旬的日照时数是影响夏玉米产量波动的关键气象因子;温光水变化趋势与玉米需求吻合。生产上要采取选用中熟和中晚熟品种、适期早播、及时灌溉排水、推迟收获等技术措施,以充分利用气候资源、趋利避害、实现夏玉米高产稳产。