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1.
科尔沁沙地乌兰敖都地区最高和最低气温的变化趋势 总被引：1，自引：0，他引：1
利用线性趋势分析方法初步分析了近25 a(1981-2005年)乌兰敖都地区逐月平均气温、平均最高气温、平均最低气温、02时平均气温、14时平均气温5个气温序列的变化趋势和特征。结果表明:近25 a来乌兰敖都地区的5个气温序列均呈非连续的增加趋势;平均最高气温线性增加率最高(0.78℃/10 a),是平均最低气温线性增加率(0.14℃/10 a)的5.6倍;平均最高气温、平均最低气温各季均为升高趋势;春季增温最明显,秋、夏、冬季的增温程度依次减小;白天气温增加幅度高于夜间,表现出明显的不对称性。 相似文献
2.
根据1961—2012年黑龙江省72个站点逐日气象资料,应用线性趋系数法对全年、四季、年代际的气温、降水、日照时数等主要农业气候资源的变化特征进行分析,结果表明,黑龙江省平均气温有明显升高趋势,升高速率为0.35℃/10 a。冬季是增温的主要贡献者,平均每10 a增加0.52℃。全年和四季平均气温的年代际变化呈增加趋势,2000s增温最明显;黑龙江省年降水量波动中呈减少趋势,减少速率为2.76 mm/10 a,减少趋势不明显,但季节性变化比较明显,秋季是降水量减少最大贡献者。年和四季降水量的年代际变化各不相同;黑龙江省全年和四季日照时数都呈减少趋势,其中,全年日照时数减少速率为26.07 h/10 a。春季是日照时数减少的最大贡献者。全年和四季日照时数随年代际变化呈非一致减少趋势。 相似文献
3.
根据天山北麓8个气象站1961—2010年气温和降水资料,采用线性趋势分析、Mann-Kendall检验、Hurst指数等方法,分析了天山北麓气温和降水的变化特征。结果表明:（1）50 a来,天山北麓年平均气温和年降水量均呈增加趋势,其变化率分别为0.26 ℃/10 a、15.67 mm/10 a;冬季增温最为明显,升温幅度达0.49℃/10 a左右,降水倾向率表现为夏季最大,为5.44 mm/10 a;（2）年平均气温和年降水量的突变年份分别在1996年和1983年;未来两者整体上呈增加趋势;（3）极端高（低）温指数在近50 a呈现增加（减少）趋势;极端降水指数中零降水日数和最长连续无降水日数呈不同程度的递减趋势,1日最大降水量和极端强降水日数以1.36 mm/10 a和1.81 d/10 a的速率递增,各极端气候指数空间差异明显;极端气温指数与年平均气温、极端降水指数与年降水量均有很好的相关性。 相似文献
4.
《中国农业气象》2010,(Z1)
本文分析了聊城市近50a来的气象资料,结果显示50a来气候发生了一定的变化,主要表现在:一是年平均气温呈明显的升高趋势。冬季气温升高最为明显,1989-2008年,出现了14个暖冬。二是降水量明显减少,平均每10a减少26.3mm。三是日照时数减少,平均年日照时数呈逐年减少趋势,夏季减少最为明显。四是极端气候事件明显增多。20世纪90年代以来,全市高温、暴雨天数呈增加趋势,旱涝灾害交替发生,频率和强度明显上升,暴雪、暴雨、冬春季气温异常偏高等极端气候事件不断出现。据预测,未来的气候变暖趋势将进一步加剧,未来气温将呈上升趋势,降水量增加,极端最高气温和极端最低气温持续上升,极端天气气候事件发生的频率可能性增大,将对农业生产产生很大的影响。 相似文献
5.
为了应对和缓解区域潜在气候变化情况,基于1901—2019年Climatic Research Unit(CRU)长时序的月平均气温和逐月降雨量格点数据集,分别采用一元线性回归法、5年滑动平均和Pettitt检验等方法分析了上合组织国家气温、降雨量的时空变化特征。结果表明:(1) 1901—2019年年平均气温和降雨量整体均呈显著增加趋势,其变化趋势分别为0.142℃/10 a(p<0.05)和2.395 mm/10 a(p<0.05),2000年之后上升最为显著。(2)气温变化具有显著的区域差异,由南向北随纬度升高变化速率逐渐加快,大部分区域小于0.2℃/10 a(p<0.05)。(3)气候变化具有显著的季节性特征。各季节气温呈显著增加趋势,春季升温速率较快(0.2℃/10 a,p<0.05),夏季气温变化速率较慢(0.08℃/10 a,p<0.05);春季降雨量变化趋势大(0.75 mm/10 a,p<0.05),夏季降雨量呈不显著的增加趋势(0.29 mm/10 a)。(4)上合组织气候突变遵循纬度分异规律,随纬度和海拔的升高突变时间推迟。综上... 相似文献
6.
近50年黑龙江省作物生长季农业气候资源的变化分析 总被引：1，自引：0，他引：1
利用1961-2010年黑龙江省28个站点逐日气象资料,应用Mann-Kendall突变检测和线性趋势系数方法分析作物生长季(5-9月)农业气候资源的变化特征,并运用降水集中度和集中期对降水条件进行分析。结果表明,研究区近50a来日照时数平均每10a减少8.8h,稳定突变点在1980年;农业热量资源显著增加,平均气温增加趋势极显著(P<0.01),最低气温升高是增温的主要贡献者,作物生长季气温突变点在1996年,比全年平均气温突变点晚了10a左右,≥10℃积温和积温日数增加也极显著(P<0.01),但积温的初、终日年际间变化较大;农业水资源减少,总降水量平均每10a减少4mm,降水量级越大,降水分配的不均匀性越突出,中雨以下降水日数显著减少(P<0.01),而大雨和暴雨降水日数增加,平均增速分别为0.5和0.45d.10a-1;降水集中期在7月下旬,且降水量级越大,其集中度越大,大雨和暴雨以上降水的集中度分别为57.7%和68.7%,极端降雨过于集中,不利于被农作物有效利用,且容易出现局地洪涝。 相似文献
7.
黔东南地区近49年的气候变化特征 总被引：2，自引：0，他引：2
利用黔东南地区16个气象观测站1961-2009年的逐日气象观测资料,采用常规统计方法和墨西哥帽小波变换方法,分析了黔东南地区近49a气温、降水、相对湿度和日照的地理分布及气候特征、年际变化趋势等。结果表明：黔东南地区近49a来年平均气温、平均最高气温的变化趋势不显著,而平均最低气温呈显著的上升趋势,其上升速率为0.146℃.10a-1;且具有3a、17a和36a的振荡周期特征,同时年平均气温具有从东南向西北递减、东部的等值线呈经向分布的特征。年平均降水量的线性变化趋势不显著但暴雨日数有显著增加趋势;年降水量具有3a和18a的准周期变化特征,同时呈由东向南、由西向北递减的趋势。年平均相对湿度的线性变化趋势也不显著,但具有3a、8a和11a的振荡周期变化特征。年平均日照时数呈显著的下降趋势,其下降速率为25.835h.10a^-1,且具有4a、10a和20a的振荡周期变化特征。黔东南地区近49a来总体上气候向暧干方向发展,同时还具有气温偏高时,降水量就偏少;气温偏低时,降水量就偏多的气候特征。 相似文献
8.
全球变化背景下新疆和田地区近半个世纪极端气温变化特征分析 总被引：1，自引：0，他引：1
对新疆和田地区1960—2013年的极端气温进行研究,以期为该区短期气候预测、生态环境安全以及灾害控制提供科学依据。通过累计距平法、滑动平均、一元线性回归趋势法、Mann-Kendall突变检验法及Morlet小波分析法,对该地区极端气温变化特征进行了分析,以探讨该地区气温变化的事实。结果表明:近54年来和田地区极端低温、极端高温分别以0.48℃/10a(p0.01)和0.19℃/10a(p0.01)的速率呈明显的上升趋势。极端低温自60年代以来呈现波动上升趋势;极端高温变化幅度较大,自60年代前期下降后波动上升,70年代后期至80年代初下降,之后波动上升,90年代末以来先下降后波动上升。极端低温、高温四季呈明显的上升趋势,均为秋季变化幅度最大,对年变化的贡献最大。年均极端高温在1997年发生突变,年均极端低温突变现象不明显。该区极端气温上升明显,向暖湿化方向发展。 相似文献
9.
为揭示雅江源区风沙化土地发育的气候变化背景,通过对雅江源区周边4个基本气象站1973-2007年的逐日气象资料进行等权平均取值.采用气候线性趋势分析法,研究了气温、降水、日照时数、风速等气象因子近35 a的变化特征及趋势.结果表明:(1)雅江源区多年平均降水量为206.12 mm,日平均气温为2.77℃、最高气温为10.72℃、最低气温为-4.81℃,年日照时数为3 295.16 h,年平均风速为2.92 m/s.(2)近35 a来,雅江源区气候变暖趋势明显,1986年以后,平均气温线性升温率为0.77℃/10 a,高于近35 a来的平均值0.47℃/10 a和珠峰地区5站平均线性升温率为0.234℃/10 a.(3)年平均降水量的波动较大,增加趋势不明显,平均增长率为0.43 mm/10 a.降水量主要集中于5-9月,占全年降水量的89.72%.年平均日照时数波动性较大,上升趋势不显著.以5月和10月较高,1月最低.年平均风速下降趋势明显,以3月最大,为3.67 m/s,11月最小,为2.20 m/s.可见,雅江源区是中国同期升温最显著的区域. 相似文献
10.
松嫩平原50年来气温及降水变化分析 总被引：12，自引：5，他引：12
运用趋势系数和气候倾向率分析了松嫩平原地区50a来气温及降水的时空变化规律。结果表明，50a来本区气温有显著上升趋势，平均气温以0．3487℃／10a幅度升高。全年各月气温均呈上升趋势，但是冬春季升温剧烈，达0．5754℃／10a；夏秋季较弱，仅为0．1868℃／10a。由于最冷月平均温度升高比最热月大，导致气温年较差减少。气温升高存在显著的区域差异，平原西北部地区增温强烈，气温倾向率大于0．45℃／10a；平原东部地区气温倾向率较低，小于0．20℃／10a。全区降水总体趋势性变化不显著，但还是呈现弱的减少趋势，平均年降水量倾向率为-0．0783mm／10a，且秋季降水减少明显。 相似文献
11.
【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。 相似文献
12.
Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. 相似文献
13.
《中国生态农业学报》2014,(8)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
14.
Aleš Lebeda Ivana Doležalová Eva Křístková Barbora Mieslerová 《Genetic Resources and Crop Evolution》2001,48(2):153-164
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions. 相似文献
15.
M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils. 相似文献
16.
Thomas Larsen Jesper Luxhøi Jakob Magid Lars Stoumann Jensen Paul Henning Krogh 《Biology and Fertility of Soils》2007,44(1):59-68
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization
and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition
with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the
decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots
with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass,
soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration,
N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially
(<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation
in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils,
indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but
the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation
for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community
performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea. 相似文献
17.
《中国生态农业学报》2014,(7)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
18.
《中国生态农业学报》2014,(6)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
19.
Grete Skrede Berit Karoline Martinsen Anne-Berit Wold Stein-Erik Birkeland Kjersti Aaby 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):193-208
Abstract A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species. 相似文献
20.
《Communications in Soil Science and Plant Analysis》2012,43(7):865-877
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils. 相似文献