西北干旱区荒漠植被生态需水量估算

基于AVHRR-GIMMS和SPOT-VEGETATION两种NDVI数据计算西北干旱区生长季植被覆盖度指数(fc),根据该指数划分阈值范围确定荒漠植被面积,并在塔里木盆地进行适用性验证。通过荒漠植被面积和参考作物蒸散量(ET0),采用潜水蒸发模型,计算西北干旱区1982—2010年荒漠植被生态需水量,以期为今后西北干旱区水资源利用和管理提供科学依据。结果表明:根据fc确定荒漠植被面积,在西北干旱区阈值范围设为0.1~0.35较为合理;1982—2010年西北干旱区荒漠植被面积总体上变化不大,呈现增-减-增的波动趋势。高、低覆盖度荒漠植被面积多年平均值分别为234.3和448.2万hm2;西北干旱区ET0空间分布总体为南疆大于北疆、东部大于西部,其中南疆、北疆及河西地区ET0多年平均值分别为1066.9、975.6和1171.6 mm。根据ET0数据拟合分析计算西北干旱区荒漠植被潜水蒸发量,其中南疆、北疆和河西地区低覆盖度荒漠植被潜水蒸发量多年平均值分别为75、64和82 mm,高覆盖度荒漠植被分别为275、233和299 mm;1982—2010年西北干旱区荒漠植被生态需水量呈减少趋势,以0.1063亿m3·a-1的速率减少,多年平均生态需水量为134.13亿m3。其中高覆盖度荒漠植被需水量多年平均为91.64亿m3,以0.3034亿m3·a-1的速率减少;低覆盖度荒漠植被需水量多年平均为42.49亿m3,以0.1972亿m3·a-1的速率增加。     

基于TVDI的甘肃省农业旱情特征及其影响因素

为探讨甘肃省农业旱情状况及其影响因素,本文利用归一化植被指数和地表温度构建特征空间,计算温度植被干旱指数(TVDI),对2001—2016年旱情进行评估,并定量分析其影响因素。结果表明:从时间尺度上看,甘肃每年均有干旱发生,且轻旱和中旱面积占比最大;从空间分布上看,干旱分布具有明显的地域分异规律,自东南向西北呈逐渐加重趋势,河西走廊大部分地区旱情较重,祁连山地区和甘南高原区很少有干旱发生;干旱出现区和非干旱出现区的形成是海拔、气温、降水、下垫面、人为干扰等多种因素综合影响的结果,其中海拔低、气温高、降水少、植被类型以荒漠为主、土地利用以沙地和戈壁为主的地区干旱面积大;气温、降水、海拔、坡度、植被类型、土地覆盖类型是甘肃省农业干旱的主要影响因素,其他因素与主要因素共同叠加,造成了甘肃省农业干旱整体上呈"东南润西北旱"的格局;利用基于植被和温度相结合的TVDI指数表征甘肃省农业干旱旱情,其计算过程简单、明了,计算结果科学准确,是今后气象部门进行旱情监测时值得尝试和应用的方法,研究结果可为甘肃省抗旱防旱和农业生产政策的制定提供科学参考。     

河西走廊植物群落特征及其与气候的关系初探

对河西走廊荒漠植物的群落类型、盖度、密度、重要值、地上生物量等进行了调查,收集整理各区域的气候资料,对它们的关系进行了初步研究。结果显示:(1)物种种类组成、总密度与海拔、经度呈正相关,与纬度呈负相关,在走廊的东南→西北方向上呈递减趋势。(2)在活动积温(>10℃)>3 200℃的荒漠地区,灌木(包括半灌木)在群落中占有绝对优势,其重要值可达到100;当活动积温在3 000℃左右时,群落往往是一些过渡类型,或以草本为优势种、以半灌木或灌木为伴生种,或以半灌木为优势种、以多年生草本为伴生种。(3)在年降水量110 mm以上的荒漠地区,植物群落生活型主要为半灌木或多年生草本;在年降水量110 mm以下的地区,生活型主要为小灌木或一年生草本;在年降水量小于50 mm的极端干旱地区,只有在雨季时有一年生草本生长。表明荒漠生态系统植被稀疏,生物量小,对气候因子,特别是降水变化敏感,对其保育显得尤为重要。     

中国西北部草地植被降水利用效率的时空格局

植被降水利用效率(PUE)是评价干旱、半干旱地区植被生产力对降水量时空动态响应特征的重要指标。利用光能利用率CASA(Carnegie-Ames-Stanford Approach)模型估算了2001—2010年中国西北七省草地植被净初级生产力(NPP),结合降水量的空间插值数据,分析了近十年草地植被PUE的空间分布、主要植被类型的PUE,及其时空格局的驱动因素。结果表明:(1)2001—2010年西北七省草地植被的平均PUE为0.68 g C m~(-2)mm~(-1)。在温带草地各类型中,PUE的大小顺序为草甸草原灌丛典型草原荒漠草原荒漠,各类型草地PUE之间差异显著;对于高寒草地而言,高寒草原的PUE显著高于高寒草甸;(2)温带草地PUE的空间分布与年降水量的关系呈抛物线形状(R~2=0.65,P0.001),PUE峰值出现在年降水量P=472.9 mm的地区;荒漠地区植被PUE的空间分布与年降水量的关系同样呈抛物线形状(R~2=0.63,P0.001),PUE峰值出现在年降水量P=263.2mm的地区;对于高寒草地而言,年降水量100 mm以下地区植被PUE变异较大,年降水量大于100 mm的地区植被PUE的空间分布随降水量的变化呈抛物线形状(R~2=0.47,P0.001),PUE峰值出现在P=559.2 mm的地区;(3)不同降水量区域,植被PUE的年际波动与气候因子的关系也有较大差别。在年降水量为200—1000 mm的地区,草地PUE的年际波动与年降水量的变化呈正相关;在年降水量高于1050 mm的地区,草地PUE的年际波动与年均温的相关性较强,相关系数最高可达到0.4。     

Woody plant encroachment may decrease plant carbon storage in grasslands under future drier conditions

木本植物沿海拔/气候梯度广泛分布于中国新疆的各种草地类型。木本植物入侵能引起草地碳储量的变化,并且气候条件会调节这种变化。基于这些研究结果,我们预测,在半干旱草地中,木本植物对半干旱草地的植被碳储量有正向影响,而在干旱草地中,木本植物会负向影响碳储量。我们调查草地类型之间地上和地下碳储量的空间分布并对这一预测进行检验。测定纯草地和木质化草地(木本植物的相对地上生物量>50%)的地上活体生物量(AGC)、凋落物量和地下生物量(BGC),共包括6种草地类型,可代表新疆地区半干旱至干旱状态。从荒漠到山地草甸,地上活体生物量、凋落物量和地下生物量逐渐增加。这一结果可能由年均降水量增加或年均气温降低导致,也表明草地类型代表干旱梯度。相比于纯草地,木本植物对草地植被碳储量的大小和分配均有显著影响。并且,由于气候的调节作用,木本植物影响的方向和强度因草地类型而异,较为湿润的条件可以促进木本植物的正向效应。相比于草本植物,木本植物的AGC高导致草地植被AGC增加。然而,随干旱程度增加,木本植物对草本植物呈现更为明显的负面效应,使得在荒漠、草原化荒漠和荒漠草原中,其木本植物对植被AGC的增加幅度小于较为湿润的草地类型。在较为干旱(MAP较低而MAT较高)的气候条件下,木本植物向根部分配的生物量较少,BGC较低并对草本植物的生产力有负面影响,从而降低荒漠、草原化荒漠和荒漠草原的植被BGC。木本植物对新疆最干旱的草地总植被碳储量有负面影响。因此,我们预测,在未来干旱的条件下,木本植物入侵可能降低而不是增加草地的植被碳储量。     

西北干旱区植被净初级生产力的遥感估算及时空差异原因

植被净初级生产力(NPP)是评价陆地生态系统的重要参数。本文基于2000—2014年的MODIS NDVI数据,结合西北干旱区的自然环境特点,从土地覆盖类型、分类的精度、辐射数据的选取、计算公式的选择等方面对CASA模型进行改进和率定,进一步估算了西北干旱区的NPP,并分析了NPP的时空变化特征。结果表明:经验证改进的CASA模型对于干旱半干旱区植被NPP的模拟效果较好,可以反映研究区的植被生长及分布状况,西北干旱区多年平均植被NPP为191.63 g C·m~(-2)·a~(-1);西北干旱区植被NPP分布具有明显的区域差异性,总体上呈现出西北、东南高,中间低的特征;在年际变化上,NPP总体上呈增加趋势,线性增长率为2.98 g C·m~(-2)·a~(-1),且不同植被类型的NPP增长率不同,耕地增长最快,其次是灌丛,最低的是林地;对西北干旱区不同植被类型的NPP与气候因子(气温、降水)的相关性分析表明,总体上植被生物量与降水的相关系数为0.538(P0.05),与气温的相关系数为0.394,说明研究区植被NPP与降水的相关性高于气温;且不同植被类型与气候因子的相关性具有差异性。     

近17年新疆干旱时空分布特征及影响因素

新疆是我国西北区重要的粮食和商品棉生产基地,受地理环境的影响,干旱频发,给社会经济及农业生产造成了巨大的损失。基于MODIS遥感数据和气象数据,估算温度植被干旱指数(Temperature Vegetation Dryness Index, TVDI),分析新疆2000—2016年干旱的年际、年内时空变化特征及其与气象因子的关系,结果表明:1)TVDI可以有效地描述新疆的干旱状况,适用于对该地区进行干旱监测;2)2000—2016年间新疆TVDI空间分布具有较强的地域分异性,呈现为天山山脉以北及昆仑山脉地区较湿润,塔里木盆地地区较干旱,新疆TVDI多年均值为0.751,整体上处于中旱状态。年内TVDI季节空间分布差异显著,不同季节的干旱程度大小为:夏季春季秋季冬季;3)新疆各地州TVDI年内月变化整体上呈现为先增加后降低的趋势,最小值在1月(0.267),最大值在6月(0.930),在14个地州中,伊犁哈萨克、阿勒泰和博尔塔拉多年间基本处于无旱状态;4)17年间不同土地利用类型干旱程度表现为林地草地建筑用地耕地,干旱类型转移的主要特点为无旱类型转入和轻旱类型、中旱类型、重旱类型、特旱类型转出;5)新疆干旱动态变化与地形、气温、降雨量以及太阳辐射等因子密切相关,其中非气象因子影响所占比例最大,降雨量与气温综合影响占面积较小,气象因子中降雨量影响所占面积较大,因此,在气象因子中新疆干旱主要受降雨的影响。     

中国西北部干旱区的植被地理分布及大农业的发展方针(续)

二、荒漠、裸露荒漠带本带是我国极端干旱地区,年降水量一般低于50—100毫米,包括塔里木盆地、东疆和柴达木盆地。塔里木盆地和东疆海拔1000—1500米,属暖温带气候。≥10℃年积温为3800—4700℃,年均温约为10—20℃;一月均温为-6到-10℃,绝对最低为-16.9℃;7月均温为25—26℃,绝对最高为43.6℃;无霜期186—230天。全境有不少面积为无植被的流动沙丘和裸露砾漠。在塔里木盆地超旱生的灌木荒漠最为突出,在山前洪积扇上有极稀疏的膜果麻黄、木坝王、泡泡刺、沙拐枣砾漠,盆地中间有极稀疏的柽柳沙漠。低     

全球变化背景下的高寒生态过程

正青藏高原是世界上海拔最高和面积最大的高原,被誉为"地球第三极"(姚檀栋等,2017),也是我国重要的生态安全屏障和战略资源储备基地(孙鸿烈等,2012)。高原气候整体上呈现"寒""旱"特征,且存在自东南向西北逐渐降低的降水梯度。沿着这一降水梯度,分布着森林、灌丛、高寒草甸、高寒草原和高寒荒漠等植被类型(张宪洲等,2015)。同时,该地区孕育了约占我国国土面积1/6的冻土(周幼吴等,     

青海省柴达木盆地及其周围山地植被

 柴达木盆地位于青藏高原东北部,其植被分布规律较复杂。东部为半干旱荒漠草原地带,地带性植被为荒漠化草原;中部为干旱荒漠地带,地带性植被为灌木和矮半灌木砾漠;西部为极端干旱裸露荒漠地带,在砾石戈壁和低山基本上无植被。本区盆地底部随着地貌、土壤和地下水的变化,出现了植被环带状分布规律。从盆地边缘向中心依次发育着洪积平原灌木、矮半灌木砾漠带,冲积平原灌木沙漠带,冲积—湖积平原灌木盐漠带,湖积平原盐生草甸带,最后为裸露盐壳和盐湖。本区山地的植被垂直带自东而西明显不同。荒漠草原地带的带谱为：山地草原—山地常绿针叶林—亚高山灌丛—高寒草甸—高山稀疏植被;荒漠地带为：矮半灌木山地石漠—高寒草原—高寒草甸—高山稀疏植被;极端荒漠地带为：裸露低山石漠—矮半灌木山地石漠,高寒草原—高山稀疏植被.     

绿洲―荒漠交错带土壤水分变化特征初步研究

 以甘肃省的民勤绿洲为例,选择土壤水分最为亏缺的7月,对白刺(Nitraria tangutorum)沙包不同迎风面,以及绿洲和荒漠交错地带的土壤水分进行了取样分析。结果表明,对于白刺沙包而言,其上层和深层土壤水分是迎风坡大于背风坡,中间层次（40～80 cm）则刚好相反。在绿洲与荒漠的交错带上,灌丛沙包与沙丘间低地水分变化有很大的不同,总体而言,丘间地水分含量大于灌丛沙包,但在距离绿洲406 m处,二者均出现一个土壤水分的最低值。在丘间地表层,水分变化是距离绿洲愈近,土壤含水量愈高;而深层土壤水分的变化趋     

腾格里沙漠东南缘人工植被区降水入渗与再分配规律研究

试验于2001年8月17日至9月30日在中国科学院沙坡头沙漠试验研究站进行,主要利用时域反射仪(TDR)连续测量土壤剖面水分含量的方法,观测受植物根系吸水,蒸散作用影响下的人工植被荒漠灌木柠条(Caragana korshinskii)群落区固定沙丘降水入渗与再分配过程。土壤体积含水率由水平埋设在植物根系剖面内12个深度层次(5～200cm)的时域反射仪探头每小时自动测定1次。天然降水条件下的土壤入渗速率由入渗深度与相应的入渗时间之比值计算得到。结果表明：在7次不连续降水过程中,土壤入渗速率与降水强度呈简单线性相关关系,土壤入渗速率约为降水强度的10倍强。然而当次降水过程中降水强度小于0．46mm／h时,土壤入渗速率约为0cm／h,此时的降水对人工植被固定沙丘区的土壤基本上没有水分补给作用。受荒漠灌木柠条根系吸水作用的影响,其根系密集剖面深度40～140cm内降水水分入渗积累不明显。降水入渗速率及入渗深度受土壤剖面初始含水率多寡而变化,干燥土壤剖面有助于提高入渗速率及入渗深度。降水以后随着时间的推移,区域环境内空气温度、湿度等气象条件适宜,柠条生长进入相对旺盛阶段,其根系密集层140cm深度处土壤含水率在总体上下降的过程中,表现出昼消夜长的趋势,翌日8：00土壤含水率值略高于前一日20：00水分值0．1％～0．3vol．％。     

Microbial Diversity in Soil,Sand Dune and Rock Substrates of the Thar Monsoon Desert,India

A culture-independent diversity assessment of archaea, bacteria and fungi in the Thar Desert in India was made. Six locations in Ajmer, Jaisalmer, Jaipur and Jodhupur included semi-arid soils, arid soils, arid sand dunes, plus arid cryptoendolithic substrates. A real-time quantitative PCR approach revealed that bacteria dominated soils and cryptoendoliths, whilst fungi dominated sand dunes. The archaea formed a minor component of all communities. Comparison of rRNA-defined community structure revealed that substrate and climate rather than location were the most parsimonious predictors. Sequence-based identification of 1240 phylotypes revealed that most taxa were common desert microorganisms. Semi-arid soils were dominated by actinobacteria and alpha proteobacteria, arid soils by chloroflexi and alpha proteobacteria, sand dunes by ascomycete fungi and cryptoendoliths by cyanobacteria. Climatic variables that best explained this distribution were mean annual rainfall and maximum annual temperature. Substrate variables that contributed most to observed diversity patterns were conductivity, soluble salts, Ca²⁺ and pH. This represents an important addition to the inventory of desert microbiota, novel insight into the abiotic drivers of community assembly, and the first report of biodiversity in a monsoon desert system.     

Long-Term Ecosystem Effects of Sand-Binding Vegetation in the Tengger Desert, Northern China

The planting of sand‐binding vegetation in the Shapotou region at the southeastern edge of the Tengger Desert began in 1956. Over the past 46 years, it has not only insured the smooth operation of the Baotou–Lanzhou railway in the sand dune section but has also played an important role in the restoration of the local eco‐environment; therefore, it is viewed as a successful model for desertification control and ecological restoration along the transport line in the arid desert region of China. Long‐term monitoring and focused research show that within 4–5 years of establishment of sand‐binding vegetation, the physical surface structure of the sand dunes stabilized, and inorganic soil crusts formed by atmospheric dust gradually turned into microbiotic crusts. Among the organisms comprising these crusts are cryptogams such as desert algae and mosses. In the 46 years since establishing sand‐binding vegetation, some 24 algal species occurred in the crusts. However, only five moss species were identified, which was fewer than the species number in the crust of naturally fixed sand dunes. Other results of the planting were that near‐surface wind velocity in the 46‐year‐old vegetation area was reduced by 54.2% compared with that in the moving sand area; soil organic matter increased from 0.06% in moving sand dunes to 1.34% in the 46‐year‐old vegetation area; the main nutrients N, P, K, etc., in the desert ecosystem increased; soil physicochemical properties improved; and soil‐forming processes occurred in the dune surface layer. Overall, establishment of sand‐binding vegetation significantly impacted soil water cycles, creating favorable conditions for colonization by many herbaceous species. These herbaceous species, in turn, facilitated the colonization and persistence of birds, insects, soil animals, and desert animals. Forty‐six years later, some 28 bird species and 50 insect species were identified in the vegetated dune field. Thus, establishment of a relatively simple community of sand‐binding species led to the transformation of the relatively barren dune environment into a desert ecosystem with complex structure, composition, and function. This restoration effort shows the potential for short‐term manipulation of environmental variables (i.e., plant cover via artificial vegetation establishment) to begin the long‐term process of ecological restoration, particularly in arid climates, and demonstrates several techniques that can be used to scientifically monitor progress in large‐scale restoration projects.     

荒漠绿洲边缘区泡泡刺种群对风沙干扰的响应

研究了位于黑河中游荒漠绿洲外缘 (荒漠与绿洲过渡带 )戈壁与沙漠两种生境下泡泡刺种群对风沙干扰的响应。结果表明 ,因风沙干扰的响应 ,泡泡刺种群以斑块状格局形式存在 ;独立灌丛沙堆的形成途径主要有 4种 :种子发育、根蘖繁殖、较大的沙堆退化 (生境破碎化 )和邻近沙堆的兼并。水分条件是泡泡刺种群生长的重要制约因素 ,长期对有限的水分资源竞争 ,使其大小和空间分布都形成了明显的特征。绿洲与戈壁交错带 (类似戈壁生境 )样地的泡泡刺种群的沙埋深度、种群高度、种群盖度、种群大小、生物量都小于绿洲与沙漠交错带 (类似沙漠生境 )样地的泡泡刺种群的相应的种群特征变量 ,而绿洲与戈壁交错带样地的泡泡刺种群密度却大于绿洲与沙漠交错带样地的相应的种群特征变量。绿洲与戈壁交错带样地的泡泡刺种群密度为33.3株 / m2 ,而绿洲与沙漠交错带样地的泡泡刺种群密度为 2 5 .4株 / m2 。两样地泡泡刺种群的沙埋深度、种群高度、盖度、密度及大小存在着显著差异 ,只有生物量无显著差异。两样地中泡泡刺的沙埋深度对泡泡刺种群特征的影响明显 ,无论戈壁还是沙漠生境 ,沙埋深度与种群高度、种群大小、种群生物量明显正相关。适度沙埋可以促进泡泡刺种群的生长 ,但当沙埋深度超过10 0 cm时 ,又会对泡泡刺种群     

Lipid accumulation in prokaryotic microorganisms from arid habitats

This review shall provide support for the suitability of arid environments as preferred location to search for unknown lipid-accumulative bacteria. Bacterial lipids are attracting more and more attention as sustainable replacement for mineral oil in fuel and plastic production. The development of prokaryotic microorganisms in arid desert habitats is affected by its harsh living conditions. Drought, nutrient limitation, strong radiation, and extreme temperatures necessitate effective adaption mechanisms. Accumulation of storage lipids as energy reserve and source of metabolic water represents a common adaption in desert animals and presumably in desert bacteria and archaea as well. Comparison of corresponding literature resulted in several bacterial species from desert habitats, which had already been described as lipid-accumulative elsewhere. Based on the gathered information, literature on microbial communities in hot desert, cold desert, and humid soil were analyzed on its content of lipid-accumulative bacteria. With more than 50% of the total community size in single studies, hot deserts appear to be more favorable for lipid-accumulative species then humid soil (≤20%) and cold deserts (≤17%). Low bacterial lipid accumulation in cold deserts is assumed to result from the influence of low temperatures on fatty acids and the increased necessity of permanent adaption methods.

     

Ecological restoration and recovery in the wind-blown sand hazard areas of northern China: relationship between soil water and carrying capacity for vegetation in the Tengger Desert

The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km2 in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain.Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas.After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert,we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water.The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition.The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession.The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed.     

Morphological description and DNA barcoding study of sand rice (<Emphasis Type="Italic">Agriophyllum squarrosum</Emphasis>, Chenopodiaceae) collected in Kazakhstan

Background

Sand rice (Agriophyllum squarrosum (L.) Moq.) is an annual shrub-like plant adapted to the mobile sand dunes in desert and semi-desert regions of Asia. It has a balanced nutrient composition with relatively high concentration of lipids and proteins, which results in its nutrition being similar to legumes. Sand rice’s proteins contain the full range of essential amino acids. However, calories content is more similar to wheat. These features together with desert stress resistance make sand rice a potential food crop resilient to ongoing climate change. It is also an important fodder crop (on young stages of growth) for cattle in arid regions of Kazakhstan. In our work, sand rice samples were collected from two distant regions of Kazakhstan as a part of the nation-wide project to determine genetic variation of the native flora.

Results

Samples were collected in western and southeastern parts of Kazakhstan separated by distances of up to 1300 km. Sequences of the nuclear ribosomal DNA ITS1-5.8S-ITS2 region and the chloroplast matK gene confirmed the identity of species defined by morphological traits. Comparison with GenBank sequences revealed polymorphic sequence positions among Kazakh populations and GenBank references, and suggested a distinction among local populations of sand rice. The phylogenetic analysis of nucleotide sequences showed a clear partition of A. squarrosum (L.) Moq. from Agriophyllum minus Fisch. & C.A. Mey, which grows in the same sand dunes environment.

Conclusions

DNA barcoding analyses of ITS and matK sequences showed a segregation of A. squarrosum from A. minus into separate clades in Maximum-Likelhood dendrograms. ITS analysis can be successfully used to characterize A. squarrosum populations growing quite distant from each other. The data obtained in this work provide the basis for further investigations on A. squarrosum population structure and may play a role in the screening of sand rice plants growing in desert and semi-desert environments of Central Asia and China.

     

不同水分下准噶尔无叶豆分株种群特征和生物量分配差异

准噶尔无叶豆是豆科无叶豆属小半灌木,在中国仅片断化分布于新疆古尔班通古特沙漠局部区域.该种自然种群种子萌发率极低(<3%),主要靠克隆繁殖维持种群.为研究克隆生长在异质性生境中的可塑性特征及其生态适应意义,对生境土壤含水量存在差异的两个准噶尔无叶豆自然种群(河边种群,沙漠种群)的分株种群特征、生物量及其分配比重进行了比较,研究发现:①在分株种群特征上,河边种群的分株显著高于沙漠种群,分株间距也显著大于沙漠种群.沙漠种群分株密度和根的密度显著大于河边种群,但每一分株拥有根的概率显著小于河边种群;②在生物量分配方面,河边种群具有比沙漠种群大的根生物量,但根茎生物量则要显著的小于沙漠种群;③在植株各部分生物量比重随植株大小的变化趋势上,河边种群各部分的比重随植株大小变化的趋势平缓,而沙漠种群各部分的比重变化趋势则较为急剧,表明河边准噶尔无叶豆分株种群随着植株的大小变化,资源分配比例并没有发生很明显的变化,而沙漠种群变化较大.结果表明,准噶尔无叶豆种群对所处生境水分条件存在可塑性响应,并通过分株种群特征变化和生物量分配差异应对水分条件的变化,形成自身的适应对策.