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东灵山地区年均降水量659.7mm,单次降水以雨量小、雨强低的降水为主。水汽压(年均17.7mb)、相对湿度(年均66%)的季节变化呈现生长季高、冬季低的趋势。年均蒸发量1019.5mm;气温、风速、日照时间和水压与月蒸发量和日蒸量相关显著;气温、日照时间和水压分别在11-6月、7-8月和9-10月为决定蒸发量的首要因子。枯枝落叶层、土壤层湿度主要受前十日降水量和坡向影响。 植物体含水量生长季节较高,冬季较低;含水量随径级的增大而降低。六个灌木树种的平均含水量大小顺序为:毛榛(48.62%)最高荆条(36.32%)最低;七个乔木树种水分含量为油松,56.14%;蒙椴,54.19%;华北落叶松,52.91%;五角枫,43.64%;辽东栎,41.87%;棘皮桦,41.13%;大叶白腊,37.79%。几种植被类型的储水量为:辽东栎林,82.08mm;华北落叶松林,47.35mm;混交林,34.60mm;油松林,31.33mm;灌丛,12.40mm。各树种叶片日最低水势的季节均值为:辽东栎,-16.1bar;五角枫,-15.8bar;大叶白腊,-15.1bar;糠椴,-13.4bar;棘皮桦,-12.3bar;蒙椴,-12.2bar。叶片水势的日间变化均呈一“V”形曲线;光照在叶片水势的日间变化中起着决定性作用。 96年各树种平均单株树干茎流量为辽东栎,30.3mm(4.19%);华北落叶松,16.1mm(2.22%);油松,8.9mm(1.23%);棘皮桦,2.9mm(0.40%)。两个生长季各林分冠层的水量平衡为:辽东栎林,树干流茎量101.87mm(9.18%),穿透降水量823.08mm(74.15%),截留量185.05mm(16.67%);华北落叶松林,树干径流量66.88mm(6.03%),穿透降水量836.92mm(75.40%),截留量206.20mm(18.58);混交林,树干径流量50.13(4.52%),穿透降水量846.78mm(76.29%),截留量212.20mm(19.12%);油松林,树干径流量33.90mm(3.05%),穿透降水量934.88mm(84.22%),截留量141.22mm(12.72%)。多元回归分析表明,树干流茎量S与降水量P和前24小时降水量P_1呈显著正相关关系;穿透降水量T与降水量P和最大雨强M正相关显著。附加截留量与降水时间成正比。 枯枝落叶层的生物量为:油松林,25.56t/hm~2;华北落叶松林20.01t/hm~2;辽东栎林,8.31t/hm~2;混交林,7.98t/hm~2。枯枝落叶层的平均实际持水量和有效持水量均以油松林最大,其次是华北落叶松林,而混交林和辽东栎林较低;枯枝落叶层的实际持水量和有效持水量的季节变化分别与前十日降水量P10成正相关和负相关关系。枯枝落叶层的截留量为油松林>华北落叶松林>辽东栎林>混交林;油松林(145.632mm和90.800mm)混交林(61.816mm和54.504mm)。油松林、辽东栎林、混交林和华北落叶松林去除枯枝落叶层后,土壤入渗量比对照平均降低100mm以上;表层土壤含水量分别比对照土壤下降了6.26、18.26、15.06和15.07个百分点。地表径流量分别增加了,辽东栎林34.299mm(603%)和15.816mm(525%);油松林14.593mm(732%)和10.584mm(1321%);混交林12.004mm(181%)和7.275mm(364%);华北落叶松林3.555mm(118%),3.275mm(229%)。96年生长季,各土壤流失量分别增加了:油松林172.751t/hm~2(124倍);辽东栎林836.500t/hm~2(119倍);混交林172.499t/hm~2(47倍);华北落叶松林11.557t/hm~2(11倍)。表层土壤容重分别增加了:油松林15.0%和20.6%,辽东栎林18.4%和28.2%,混交林11.5%和38.5%,华北落叶松林4.3%和17.1%。 0-60cm深度土壤容重平均值的大小顺序为:草地>灌丛>辽东栎林>油松林>混交林>华北落叶松林;而土壤孔隙度的大小顺序为华北落叶松林>混交林>油松林>辽东栎林>灌丛>草地。两个生长季为土壤实际储水量的均值:油松林,124.45mm,78.62mm;辽东栎林,131.23mm,87.72mm;混交林,180.41mm,113.90mm;华北落叶松林,165.53mm,127.95mm;灌丛,172.50mm,89.81mm;草地,152.92mm,89.59 mm分别比干旱年份97年高出45.83mm、43.51mm、51.63mm、37.58mm、82.69mm和63.33mm。两个生长季的地表径流量为草地,30.930mm(2.79%);灌丛,16.321mm(147%);油松林,2.911mm(0.26%);辽东栎林,8.703mm(0.78%);混交林,8.625mm(0.78%);华北落叶松林,4.447mm(0.40%)。油松林、混交林和华北落叶松林地表径流量与降水量P(mm)和最大雨强(mm/h)正相关显著;而辽东栎林、灌丛和草地的地表径流量则与降水量P(mm)、平均雨强Q(mm/hr)和最大雨强M(mm/hr)三者之间呈显著正相关关系。与草地相比(1220.093kg/hm~2,100%),灌丛、辽东栎林、混交林、油松林和华北落叶松林96年生长季的土壤流失量分别降低了85.05%、94.26%、96.99%、98.86和99.14%。 降水量是影响小流域径流量时间变化的主要因素;南沟和马牙石沟96年的径流量分别是97年的8.19倍和7.87倍,而径流深(46.25mm,52.75mm)分别比97年(5.65mm,6.70mm)高出40.60mm和46.05mm。两个小流域由于面积的差异而使南沟两年的径流量分别比马牙石沟高出2773.136m~3(13.15%)和235.434m~3(8.79%)。96年和97年马牙石沟径流深比南沟高出6.5mm(14.05%)和1.05mm(18.58%)。在地处大陆性季风气候区的东灵山地区,用0.010m~3/min/km~2/hr能较好地分割小流域的洪峰和基流。在五次暴雨水文曲线中,马牙石沟的快速径流量分别比南沟高出25.00%到143.33%。五次洪水水文响应R的平均值南沟为0.218%,马牙石沟为0.404%;与海洋性气候地区相比,东灵山地区小流域的R值要低一到两个数量级。马牙石沟洪峰流量Qp的平均值为418.772L/min要比南沟(281.191L/min)大48.9%。东灵山地区小流域的洪水径流过程可分为三种类型。

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我国北方温带草原地处干旱半干旱区,是欧亚大陆草原生物区系的重要组成部分,也是我国重要的畜牧业生产基地。土壤氮素作为陆地植物生长和生态系统初级生产力的主要限制因子之一,了解其矿化和可利用性对各种人为干扰因素的响应,有助于我们充分认识草地退化机理,维持草场生产力并进一步促进畜牧业的可持续发展,为草地恢复、重建和维护提供理论依据。本实验在中国科学院内蒙古草原生态系统定位研究站的多年围封退化样地,分别实施了火烧、施肥、刈割及其交互作用的人为干扰处理,利用原状土野外培养的方法,在两年时间中,研究不同的人为干扰因素(火烧、施肥、刈割及其交互处理)对土壤净氮矿化作用的影响。 火烧显著影响草原的氮循环过程,季节和年际的气候变化参与调节氮循环对火烧处理的响应。多年围封后的初次人工火烧处理显著降低了第一个生长季(2006 年生长季)和其后冬季的土壤净氮矿化速率,但是,火烧处理仅在冬季对土壤无机氮含量产生显著降低作用;2007 年生长季,火烧处理对土壤净氮矿化速率和土壤无机氮含量没有显著作用,但是在个别月份,不同的火烧频率对土壤净氮矿化速率和无机氮含量的影响表现出差异。2006 年生长季,未火烧样地和火烧样地净氮矿化积累量分别为3.07±0.26 g N m-2 和2.18±0.21 g N m-2;冬季,未火烧样地和火烧样地净氮矿化积累量分别为1.18±0.25 g N m-2 和0.51±0.08 g N m-2;2007 年生长季,未火烧样地(BC)、每年火烧样地(B1)和两年一烧样地(B2)净氮矿化积累量分别为1.32±0.21 g N m-2、0.54±0.30 g N m-2 和 0.77±0.24 g N m-2。较为湿润的2006 年生长季的净氮矿化积累量显著高于较为干旱的2007 年生长季,冬季也存在相当丰富的净氮矿化积累量。我们推论,长时间围封后的单次火烧处理对土壤净氮矿化作用的影响可能是短效的,但是年际间气候变化对土壤净氮矿化作用影响显著。 施肥显著提高了土壤的无机氮含量,并且与施肥梯度呈显著正相关关系。施肥对土壤无机氮含量的影响具有累加效应,第一次施肥和第二次施肥后的首次取样,+N5.25 、+N17.5 、+N28.0 三个施肥梯度的样地土壤无机氮含量比未施肥样地分别高出56%、219%、1054%和514%、891%、1811%。施肥处理在2006 年和2007 年对土壤净氮矿化作用都没有显著影响,仅在2007 年的个别月份有一定效果。以上结果说明,无机氮肥的添加可以明显提高土壤中无机氮的含量,满足植物生长的需求,但对于土壤氮转化过程的影响可能还要受其它环境和生物因子的制约。 刈割对土壤无机氮含量和净硝化速率没有显著作用,对土壤净氮矿化速率仅在个别月份表现显著效果。2007 年生长季,未刈割样地和刈割样地净氮矿化积累量分别为1.32±0.21 g N m-2 和1.08±0.35 g N m-2,不存在显著差异。我们推论,长期围封后的单次刈割处理在短期内对生长季的土壤氮动态仅有微弱影响,并且这种效果还可能受水分因素的制约。 火烧、施肥、刈割的交互处理在2007 年生长季对土壤无机氮含量产生显著作用,但是,对土壤净氮矿化速率和净硝化速率没有显著效果,然而,在不同的取样时间,火烧、施肥、刈割的交互处理对土壤无机氮含量、净氮矿化速率和净硝化速率的影响存在显著差异,说明火烧、施肥、刈割的交互处理对土壤无机氮和净氮矿化作用的影响可能受各种环境因子的制约,尤其是在水分相对缺乏的半干旱内蒙古草原,非生物因子和生物因子可能共同影响着土壤中的氮平衡。 本研究初步分析了长期围封后火烧、施肥、刈割及其交互处理对土壤净氮矿化的影响,初步探究了人为干扰和环境气候变化对土壤可利用性氮的调节作用,为科学地进行禁牧、割草、人工养份添加等草原管理提供了数据支持。

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Till now there have been only two families of Bivalves with four genera known from freshwater in Ceylon. The material used for this study consists of members of three genera. This study deals with the family Unionidae, the family Corbiculidae is only represented by one specimen.

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世居云南的少数民族中,壮、傣、水、布依、布朗、德昂、佤、彝、白、怒、哈尼、傈僳、拉祜、纳西、景颇、阿昌、基 诺和独龙18 个民族是由“羌”、“濮”、“越”3 大部落群体演化而来,是云南的土著居民。利用PCR2RFL P 方法对这18 个土著民族进行Y染色体上13 个双等位基因位点进行基因分型。结果显示,不同历史族源的民族群体在Y染 色体双等位基因单倍型分布上具有一定的差异:在百越后裔民族群体中以单倍型H11 、H12 为主要分布;在氐羌后 裔民族中以单倍型H5 、H6 和H8 为主要分布;在百濮后裔民族群体中主要单倍型分布为H6 、H8 和H11 。进一步 主成分分析表明,百越后裔民族群体和氐羌后裔民族在主成分图上聚为两组,提示父系基因库有不同的来源,与历 史记载相印证。

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Data, information gaps and related monitoring requirements including trans-boundry issues; alternative livelihoods; critical habitat and develoment issues; policy, planning and institutional development.

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Establishment of a working group of regional experts in Marine Protected Areas (MPAs); inventory and status of existing MPAs; gap analysis;establishment of common data requirements and protocols;development of a regional action plan;training and capacity building; outreach activities; proposal f0r management of existing and creation of new MPAs.

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In this study the process of female gray mullet brooders was carried out by using histological study and masurment of sex steroids. Results of histological studies showed that oocyte of gray mullet brooders in Gomishan Rearing Center conditions of develop to the end of yolk globule stage. The results were observed with oocyte in chromatin nucleolar stage (first stage) with means of diameter of 20 p m, in August, perinucleolar stage (second stage) in September with mean diameter of 87 p m, yolk vesicle stage (third stage) in October with mean diameter 200 p m and yolk granules stage (forth stage) from October to November with average diameter of 180 — 650 p m. For the reason of stopping oocyte develop at the end of fourth stage, hormonal induction to final oocyte maturation and ovulation was used. For this purpose, carp pituitary , HCG and LRH-A2 with different combinations were used in two stages, second injection was used 24 hours after first injection. 15 females brooders were divided in 5 groups, different hormonal combinations were injected to four groups and to fifth group as control, only saline, was injected. The process of female brooder rippening in hormonal induction was studied via masurment of sex steroids including 17 a - hydroxy progestrone, estradio1-17)6 and testosterone. Blood samples were collected from caudal vein during first injection, 24, 30 and 48 hours after the first injection. At the same time, for distinguishing histological changes the sample has been attained from the gonads Sex stroid fluctuation patterns in different brooder groups that injected hormon were similar, however hormonal composition had similar effects. All brooder that their oocyte in the beginning of hormonal injection were At the end of fourth stage with oocyte diameter average of 600 p m received to final maturation and ovulation. The brooder that its oocytes were At the begining or mid-fourth stage did not show ovulation but hormonal induction caused oocyte develop at the beginning of fifth stage. Study of 17-hydroxy progestrone fluctuation showed that the maximum level of this steroid (0.347 ng/ml) measured 30 hours after the first injection and was significantly higher (p< 0.05) than those of control group. So, 17-hydroxy progestrone is probably precursor of maturation inducing steroid (MIS). However the maximum level of that observed was coincident with germinal vesicle breakdown, oil droplets coalescence and dissolution of yolk granuls The maximum levels of esteradiol— 17/0 and testosterone (3.778 and 16.801ng/ml,respectively) in spawned brooders,were observed 24 hours after the first injection. levels of those steroids were significantly higher (p<0.05) than control group. Maximum level of sex steroids in the brooders that did not spawn to the end of treatment was observed with more delay than those in spawned brooders. Therefor maximum level of 17a-hydroxy progestrone (0.264 ng/ml) in those brooders observed in fourth sampling time and the maximum levels of estradio1-17a and testosterone (2.944 and 18.993 ng/ml, respectivly)observed in third sampling time that was significantly higher (p<0.05) than those of control group. For the study of stress effect on brooders during the hormonal induction, level of cortisol was measured in every sampling time. level of cortisol had high fluctuation that showed handling level and stress effect on brooders. However maximum level of cortisol in majority of brooders was dominant in third sampling time that was coincident with final maturation.

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Objectives included; a contribution to understanding large-scale processes affecting the Bay of Bengal Large Marine Ecosystem Project (BOBLME) and it's living resources; and to align with International Indian Ocean Expedition (IIOE-2) (2015-2020) which will extensively explore and study the Indian Ocean to improve understanding of the ocean and coupled climate processes.

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记述采自中国云南卷叶象甲科狭额卷象属Euops 1 新种:福贡狭额象(Euopsfugongensis Liang et Wang,sp.nov.).它与近缘种九寨狭额象E.jiuzhaiensis的区别在于九寨狭额象的体色黑褐,有金属光泽,前胸背部无皱纹.正模:♂,云南福贡,1 300 m,1990-Ⅵ-18,梁醒财采.模式标本保存于中国科学院昆明动物研究所.