Basesd on the precipitation difference in Tsaidam Basin of Qinghai Province, three sampling areas, including Geremu, Delinghan and Doulan, were selected, and then three sapmling plots in each sampling area were selected to study the characteristics of plant community which dominated by Ceratoides lateens, Nitraria tangutorum, Tamarix chinensis, Kalidium gracile, Haloxylon ammodendron and Salsola arbuscula respectively. At the same time, the morphological and physiological features of above-mentioned 6 species were measured for probing their drought tolerance. By using the subordinative function method, grey correlative degree analyse and no-weight index comprehensive evaluation method, their drought tolerance were compared as well. The results were showed as follows: The main xeric vegetation types in the desert steppe of Tsaidam Basin were Nitraria tangutorum community, Tamarix chinensis community, Haloxylon ammodendron community, Kalidium gracile+Salsola arbuscula community, Ceratoides lateens+ Haloxylon ammodendron+Kalidium gracile community.

根據(jù)青海省柴達(dá)木盆地不同地區(qū)歷年降水量差異，在研究區(qū)內(nèi)選擇格爾木中文字幕第23页、德令哈AAAAAA黄色片、都蘭3個(gè)采樣區(qū)在线国产黄色片，每個(gè)樣區(qū)內(nèi)確定3個(gè)采樣點(diǎn)(表示為D11、D12另类专区另类在线观看视频、D13、D21思思伊人久久大香线蕉av、D22日本在线A级黄页网站、D23、D31国产欧美二区第一页、D32人人曰人人曰、D33)，以樣區(qū)內(nèi)唐古特白刺99riav.com、甘蒙檉柳国产美女裸精品视频、梭梭、木本豬毛菜92国产精品午夜福利视色、里海鹽爪爪最新超碰在线、駝絨藜等6種主要植物為研究對(duì)象，通過調(diào)查采樣地區(qū)群落特征J8又大又粗又长又硬不爽，觀測(cè)植物形態(tài)解剖特征日韩一级特黄高清免费，測(cè)定植物脯氨酸、可溶性糖综合在线视频精品专区、葉綠素色色的视屏儿黄、超氧化物歧化酶、過氧化物酶和過氧化氫酶等生理指標(biāo)性爱在线视频网，研究了柴達(dá)木盆地6種植物抗旱生理特性及抗旱特性免费A级毛片无码免费视频120软件，用模糊數(shù)學(xué)隸屬函數(shù)法、灰色關(guān)聯(lián)分析和非加權(quán)指數(shù)評(píng)價(jià)法分別對(duì)6種植物的各個(gè)抗旱性指標(biāo)進(jìn)行了綜合評(píng)價(jià)国产视免费性爱视频。

The cause of the heat-wave during the drought is the intensified Rossby wave over the Eurasia continent,which results in a closed warm anticyclone over the drought area,then an adiabatic warming is caused by the strong sinking motion.

華北地區(qū)夏季熱浪天氣的成因：(1)夏季歐亞大陸Rossby長(zhǎng)定波波列的維持并發(fā)展农村片人人操，使得干旱區(qū)域上空出現(xiàn)閉合暖性高壓系統(tǒng)，其強(qiáng)烈下沉運(yùn)動(dòng)引起空氣絕熱增溫(2)局地干旱維持與發(fā)展使得干旱區(qū)內(nèi)潛熱大大降低色图综合亚洲，近地面感熱以及向上長(zhǎng)波輻射的增加使得干旱區(qū)域氣溫持續(xù)升高牲一交一乱一伦A片。

The results showed that the photosynthetic rate of B.stamineus decreased with the increasing of the drought gradient,but the decrease amplitude was less.The photosynthetic rate of B.inermis decreased indistinctively with the increasing of the drought gradient in the prometaphase,decreased distinctively in the later stage.

結(jié)果表明：美國(guó)無芒雀麥的光合速率基本上隨著干旱梯度的增加而逐漸下降，在不同脅迫天數(shù)間也逐漸下降一级二级三级a片，但下降幅度較信访览细韭易印；本地?zé)o芒雀麥各干旱處理光合速率在脅迫前中期隨脅迫梯度的增加下降不明顯国产老熟女视频一区二区，到脅迫后期才表現(xiàn)出較為明顯的下降趨勢(shì)91精品在线观看视频，但在各脅迫天數(shù)間差別不大，僅在脅迫第20 d各處理光合速率較之前有較為明顯的降低日韩精品成人网页视频。

Under field continuous drought stress, growth rate, branches of stolon, leaf lengthobviously declined, nevertheless, leaf water content increased and MDA content decreasedsignificantly during field water deficit. SOD activity of the four turf grasses increased at thebeginning of water deficit and then decreased with drought stress. POD activity ofAugustinegrass increased rapidly and then kept stable with water deficit, however, PODactivity of Centipedegrass changed indistinctively.

田間持續(xù)干旱下欧美乱强伦，隨干旱時(shí)間的延長(zhǎng)黄色网站淫乱片，鈍葉草和假儉草匍匐主莖的生長(zhǎng)速率、主莖分枝數(shù)以及葉片長(zhǎng)度顯著(P＜0.05)下降国产AAA级毛片A片；葉片含水量呈上升趨勢(shì)最新国产在线视频；葉片MDA含量呈下降趨勢(shì)(P＜0.05)；葉片SOD活性總體上呈先上升后下降趨勢(shì)AV字幕在线观看，但德陽假儉草和宮崎鈍葉草峰值出現(xiàn)較早jiuse200；鈍葉草葉片POD活性先上升(P＜0.05)后趨于穩(wěn)定，而假儉草葉片POD活性變化不顯著丝袜日韩中文无码视频；四個(gè)草坪草葉片CAT活性先下降(P＜0.05)后趨于穩(wěn)定99爱国产。

Drought-resistant germplasms were mainly origin in low temperature, frequently drought, poor soil region, such as Wangmo, Luodian, Rongjiang, Ziyun and so on.

抗旱種質(zhì)多來源于貴州省低熱的望謨、羅甸97人操人人插人人搞、榕江国产精品久久无码AV片、紫云等干旱頻繁發(fā)生、土壤貧瘠的地區(qū)人人操人人爽超碰。

The results were as follows: under light or medium water stress, the changes of RWC, Pro, RCC, MDA and SOD were similar, membrane penetration and membrane lipid peroxidation aggravated, osmotic modulation ability and enzyme protection system strengthened; physiological modulation ability declined under severe water stress. Almonds subjected to drought in the condition of below 3.77% soil water content. Altogether Fritz and Nonpareil both had stronger resistant drought adaptation.

結(jié)果表明欧美性爱十四页，在受到輕度和中度脅迫過程中，扁桃幼苗葉片的Prowww色五月、RCC黄色网站免看、MDA以及SOD都出現(xiàn)相似變化趨勢(shì)，細(xì)胞膜透性和膜脂過氧化程度逐漸加劇欧美野外打野战A片视频，滲透調(diào)節(jié)能力和酶保護(hù)系統(tǒng)增強(qiáng)一级毛片免费播放在线视频尤；在重度脅迫時(shí)，其生理調(diào)節(jié)能力下降玖玖玖无码视频，當(dāng)達(dá)到土壤含水量3.77%以下的重度脅迫時(shí)免费黄色网址久久，就會(huì)受到旱害；總體而言日本黄色视频日本黄色视频，兩個(gè)供試品種扶茲和那普瑞爾都具有較強(qiáng)的抗旱適應(yīng)性久久久久久久久久久久久。

The results show : a moderate drought, increased activity of SOD, and the drought will cause excessive SOD activity or decreased active oxygen scavenger. Oxalis corymbosa reflected a higher foreign species protected activity, which is consistent with a strong ability to invasion.

實(shí)驗(yàn)結(jié)果表明：在適度的干旱下，SOD活性有所上升欧美性爱23TB，而過度的干旱則會(huì)使SOD等活性氧清除劑活性或含量下降911精品视频天天看，反映了外來物種銅錘草有更高的保護(hù)酶活性，這與其較強(qiáng)的入侵能力是一致的一a级视频。

Concerned by the recurrent drought, which still affects millions owing to the serious crop failures in drought-prone parts of the country and the pastoralist areas that have weak infrastructures and low development capacities

關(guān)切旱災(zāi)一再發(fā)生国产盗摄正在播放一区，而且由于該國(guó)基礎(chǔ)設(shè)施薄弱、發(fā)展能力低的易受旱災(zāi)地區(qū)以及牧區(qū)農(nóng)作物又嚴(yán)重歉收A片免费视频网站入口，受旱災(zāi)影響的人數(shù)仍以百萬計(jì)

Some researchers believe that the latter area possesses savanna vegetation. Savannas are closely associated with seasonal drought, and they may be defined by climatic climax vegetation in tropical and subtropical areas. Based on the ecoclimatic analyses as well as the surviving vegetation in Taiwan, we inferred that the potential natural vegetations of these 2 semi-arid regions were not savanna but forest with some drought-deciduous trees. In conclusion, the physiognomic type of grassland dotted with trees may occur in small areas at present, but Taiwan lacks climate-shaped savanna climax vegetation.

本研究將疏林定義為分布於熱帶及亞熱帶之氣候形塑的極相植群欧美一区二三区，氣候分析結(jié)果表明臺(tái)灣半乾旱區(qū)域之缺水逆境并不嚴(yán)重，再配合現(xiàn)生殘存植群之觀察黄色免费观看网站网址，發(fā)現(xiàn)臺(tái)灣有形相為疏林的現(xiàn)生局部性植群凹凸黄色视频免费观看，但其潛在自然植群應(yīng)為參雜有乾旱落葉之闊葉樹種的森林日操av在线播放，并不存在較大面積之潛在的氣候型極相疏林。

For drought tolerant genotypes, the relative value of proline content, SOD or CAT activity of plumule should be larger than 2.2, 0.8 and 0.8, respectively, while for drought sensitive ones, the relative value should be less than 1.5, 0.65 and 0.4, respectively.

滲透脅迫條件下胚芽鞘脯氨酸人人摸人人摸操、CAT和SOD的T/CK值分別大于2.2色交网站、0.8和0.8為強(qiáng)抗旱性品種，而抗旱性弱的品種則分別小于1.5无码一区二区久久免费、0.65和0.4www.久久cao。