天山博格达峰西北麓盐生植物群落及其化学元素特征

天山博格达峰西北麓盐生植被的种类组成７３种，优势科依次为藜科、豆科、十字花科、禾本科、柽柳科、菊科、蒺藜科。生活型组成以地面芽和一年生植物最多，前者占２２％，后者达４５．２％，组成该区盐生植被的层片１１个；盐生植物群落类型多样，其中盐柴类荒漠植被的景观意义最大，在该地区颇具代表性；据１５种占优势的盐生植物元素化学成分含量高低顺序，按元素化学成分，对它们进行排序，划分了盐生植物群落类型和该区盐生植被的元素化学特征。除此之外，从科的角度还初步拟定了科的元素的化学特征型，并对灰分含量的高、低也进行了排序。     

天山乌鲁木齐河源区高山带植被及其生物多样性初步研究

本文以天山乌鲁木齐河源区为研究范围，对其植物种类组成，植被类型，物种的多样性等进行了初步探讨。结果表明，该区域共有高等植物17种41属57种其中以禾本科（8种），菊科（7种），毛莨科（7种），莎草科（5种）和十字花科（5种）占优势，该区域植被包含了两个垂直带；高山草甸和高山垫状植被，另外在高山流石滩上也出现了处于演替早期阶段的高山植物群聚，根据中国植被的植被分类原则，共划分出了苔草群系（Form.Carexsp)。嵩草群系（Form.Kobresia sp)，高山莓群系（Form.Sibbaldia terandra)，高山红景天群系（Form.Rhodiola coccinea)，柔子草群系（Form.Thylacospermum caespitosum)等5个群系18类植物群落，利用Simpson指数和Shannon-Wiener指数所作的生物多样性分析表明，高山流石滩植被的多样性最低，而以垫状植被的生物多样性最高；同时，在研究区300m的海拔高程范围内，其多样性指数呈现出随海拔高度增加而递减的变化趋势。     

哈纳斯自然保护区植被特点及植物区系形成的探讨

哈纳斯自然保护区的植被充分反映了欧洲－西伯利亚区系成分的特色。山地针叶林带与天山相比显著下降，为阴暗泰加林类型。植被类型丰富多样，与天山的植被特点迥然不同。本区植物区系形成于第四纪。其区系组成以温带成分为主，并含有少量的古地中海成分。以本土发生的安哥拉区系成分米体；发源于华夏地区的亚洲温带成分渗透至本区；残存的古地中海成分有小部分通过相邻地区向本区渗放。     

浑善达克沙地白槽沟植物资源研究

浑善达克沙地白槽沟发育有不同于沙地的植被类型,且种类多、丰富度高、盖度高.通过对白槽沟的植被调查,分析该地植物区系、植物组成、群落结构,结果表明:1)研究区有维管植物360种,以中生多年生草本及东亚成分最丰富;分属于73科224属,以菊科种数最多,其次为禾本科,显示出沟谷区域的植物多样性较沙地强.2)植物的生活型组成中多年生草本占优势,占全部维管植物的60％;以中生植物为主,占研究区全部维管植物的61％,其次为旱生植物,湿生和水生植物较少,显示白槽沟所处的位置是半干旱区的特点.3)植物种的区系类型可划分为16个,物种中有丰富的药用植物、观赏植物、食用植物、编织用植物等多种资源类型;植物群落可划分为针叶林、阔叶林、灌丛、半灌木丛、草原甸、沼泽和水生植被,共46个群系,表明了白槽沟沟内与两岸沙地植被的极显著差异.浑善达克沙地白槽沟为沙质地层的下切沟,沟谷特殊的微地形环境是影响植物种类和区系多样性的主导因素,特殊的地形引起植被的显著变化,沟内生境多样,植被类型多样,是浑善达克沙地微地形环境最为良好的地段.     

鄂尔多斯高原西部阿拉巴斯山地区第三纪残遗植物避难所的自然保护问题

阿拉巴斯山地区为干旱区第三纪残遗植物的避难所,是内蒙古地区植物特有现象最明显的地区。共有维管植物251种。地带性植被为草原化荒漠,主要群落类型为四合木荒漠、半日花荒漠、绵刺荒漠、沙冬青荒漠等荒漠群系。以戈壁种和东阿拉善种为主的荒漠成分构成了本地区植物区系的主体。古老残遗种及特有种在植物区系和植被组成中均起主导作用。但是这块宝地目前面临严重破坏,应该尽快成立阿拉巴斯第三纪残遗植物保护区。     

呼伦贝尔退化草地植被演替特征研究

由于气候环境条件的变化和人类长期不合理的草地利用方式,致使呼伦贝尔草原退化、沙漠化趋势加剧,草地的退化严重威胁着当地的生态环境,制约着畜牧业的发展。对草甸草原、典型草原和沙地植被三种草地类型的植被退化演替特征研究结果表明:随着草地退化(沙化)程度加大,群落结构与多样性逐渐丧失,草层高度、植被盖度、株丛密度、地上部生物量等,都呈现不同程度的递减趋势,草地退化过程中,群落物种组成逐渐单一,数量逐渐减少,物种组成发生显著的变化。未退化草地以禾本科植物占主导地位,随着退化程度的加大,退化指示类的菊科植物的重要地位得到提升,中度退化阶段蔷薇科植物不断增加,并占据优势地位,重度退化阶段,多以耐践踏的蔷薇科植物和小型禾草为优势种,其中重度沙化草地,多年生植物几乎全部消失,而被一年生植物替代。     

内蒙古额济纳蒙古族荒漠景观多样性传统知识分析

内蒙古额济纳蒙古族民间以不同的名称来区分的景观类型有26种，包括自然景观20种和人文景观6种。民间对景观的分类可称之为“民间景观类型”(folk landscape type)。“民间景观类型”中的自然景观主要根据植被建群植物、地形地貌与植被特征、地势地貌特征和地表水域特征命名；而人文景观主要根据人工建筑设施的名称来命名。额济纳蒙古族民间对景观类型的划分与景观生态学的景观生态类型的划分存在着很高的一致性。“民间景观类型”是民间利用和管理景观的基础，具有重要的科学参考价值和文化多样性意义。     

新疆沙冬青群落的区系组成与结构特征

在乌恰县不同分布地点的新疆沙冬青群落中随机设置10个样方,对新疆沙冬青群落种子植物的科、属、种的组成及其结构特征进行调查.结果表明:新疆沙冬青群落由22科39属62种种子植物组成,群落物种较为丰富,科的区系以世界分布类型为主,属的区系以地中海-中亚-西亚成分为主,区系地理成分古老而复杂.新疆沙冬青群落的水平结构,大部分植物以丛生形式在群落中聚集分布,少数植物散生于群落中;群落的垂直结构,按生长型可分为2层(灌木层、草本层)和6个层片,构成新疆沙冬青群落的植物,其中草本和半灌木种类较多,所占的比例较大.群落中草本层片占植被总覆盖度的15%～31%,新疆沙冬青群落属于草原化荒漠植被类型.     

天山1号冰川冻原植被带种子植物区系

新疆天山１号冰川附近冻原植被带有野生种子植物１９科４６属６６种。通过该地植物的区系分析，表明该地区的植物区性质明显温带性，且以北温带成分为主，地理成分复杂，３７个分布区类型和５个变型。     

策勒绿洲边缘自然植被恢复重建的盖度指标

策勒绿洲位于塔克拉玛干沙漠南缘，绿洲边缘的自然植被带是保护绿洲的天然屏障，近50年来，绿洲边缘的自然植被带遭到严重破坏，绿洲生态系统受到沙漠化的严重威胁，恢复重建绿洲边缘自然植被带的限制因素是水，通过综合研究确定具备可靠防护功能的不同植被类型的盖度指标，是恢复重建绿洲边缘自然植被过程中节约用水的基础，本研究通过对策勒绿洲边缘沙物质的粒度分析，起动风速的风洞实验，绿洲边缘风速的长期测定以及不同植被类型防护效益的野外观测，确定策勒绿洲边缘不同植被类型的盖度指标为：●柽柳灌木群落盖度：≥20%；●骆驼刺草本植物群落盖度：≥30%；●花花柴草本植物群落盖度：≥30%；●芦苇草本植物群落盖度：≥30%。     

Hyper-spectral characteristics of rolled-leaf desert vegetation in the Hexi Corridor,China

Desert plants survive harsh environment using a variety of drought-resistant structural modifications and physio-ecological systems. Rolled-leaf plants roll up their leaves during periods of drought, making it difficult to distinguish between the external structures of various types of plants, it is therefore necessary to carry out spectral characteristics analysis for species identification of these rolled-leaf plants. Based on hyper-spectral data measured in the field, we analyzed the spectral characteristics of seven types of typical temperate zone rolled-leaf desert plants in the Hexi Corridor, China using a variety of mathematical transformation methods. The results show that:(1) during the vigorous growth period in July and August, the locations of the red valleys, green peaks, and three-edge parameters, namely, the red edge, the blue edge, and the yellow edge of well-developed rolled-leaf desert plants are essentially consistent with those of the majority of terrestrial vegetation types;(2) the absorption regions of liquid water, i.e., 1400–1500 and 1600–1700 nm, are the optimal bands for distinguishing various types of rolled-leaf desert plants;(3) in the leaf reflectance regions of 700–1250 nm, which is controlled by cellular structure, it is difficult to select the characteristic bands for differentiation rolled-leaf desert vegetation; and(4) after processing the spectral reflectance curves using a first-order differential, the envelope removal method, and the normalized differential ratio, we identify the other characteristic bands and parameters that can be used for identifying various types of temperate zone rolled-leaf desert plants, i.e., the 510–560, 650–700 and 1330–1380 nm regions, and the red edge amplitude. In general, the mathematical transformation methods in the study are effective tools to capture useful spectral information for species identification of rolled-leaf plants in the Hexi Corridor.     

巴丹吉林沙漠植被群落特征与土壤水分关系研究

通过对巴丹吉林沙漠周边及腹地进行野外调查采样,归纳出该区植被的生活型和群落类型,分析其植被多样性、优势度及均匀度指数,进而探讨该地区植被群落特征对土壤水分的响应。结果表明:(1)本次调查共记录到20科52属56种植物,分属于乔木、小乔木、灌木、小灌木、半灌木、草质藤本、多年生草本、一年生草本8类生活型,群落多以灌木和多年生草本植物为主,且多为沙漠旱生或超旱生多年生植物;(2)巴丹吉林沙漠群落整体生物多样性指数偏低,沙漠腹地湖泊周围物种丰富度和多样性指数相对较高,边缘地区较低,且灌木层在群落中占优势且分布均匀,草本层植被种类多样;(3)巴丹吉林沙漠土壤含水量普遍较低,超过61%的区域土壤含水量不足5%;土壤含水量与Simpson优势度指数(C)为极显著负相关,与Shannon-Winner多样性指数(H′)、Simpson多样性指数(D)、Alatato均匀度指数(Ea)均为极显著正相关,且Simpson优势度指数(C)、Shannon-Winner多样性指数(H′)、Simp?son多样性指数(D)对土壤水分的响应关系中均为立方函数拟合效果最好。     

沙坡头人工植被组成分析

本文根据多年的植被调查和沙层水分动态的观测资料,对沙坡头地区无灌溉条件下人工植被33年演变过程中的组成进行分析。结果表明:(1)目前,人工植被已经演变为以油蒿为主的灌木半灌木+一年生草本+孢子植物占优势的人工——天然植被。(2)人工植被的生活型以高位芽植物和一年生植物为主,辅以少量的地面芽植物,没有地上芽和隐芽植物,生活型谱不完整。与天然油蒿群落比较,人工植被种类少、投影盖度低、根栖层水分严重亏缺。(3)投影盖度是荒漠半荒漠植被最重要的特征之一。人工植被演变初期投影盖度波动性上升。7—16龄为鼎盛时期,投影盖度为30%左右。随后又波动性下降。这种波动性变化规律在判断沙漠化程度时有意义。(4)人工植被演变过程中Shannon-Wiener多样性指数的变化规律近似“∩”型。种优势度指数的变化规律与其成负相关,近似“U”型。(5)流沙群落、3—33龄的人工植被的种多度分布模式为几何级数型。天然油蒿群落和红砂—珍珠群落为对数正态分布。1—2龄的人工植被种多度分布模式完全受人为因素的制约。     

The role of glacial gravel in community development of vascular plants on the glacier forelands of the Third Pole

On a deglaciated terrain, glacial gravel is the primary component of the natural habitat for vascular plant colonization and succession. Knowledge regarding the role of glacial gravel in vascular plant growth, however, remains limited. In this study, an unmanned aerial vehicle (UAV) was used to investigate plant family composition, species richness, fractional vegetation cover (FVC), and gravel cover (GC) along elevational gradients on the three glacier forelands (Kekesayi, Jiangmanjiaer, and Koxkar Baxi) of the Third Pole (including the eastern Pamir Plateau and western Tianshan Mountains) in China. We then analyzed the spatial characteristics of vascular plants followed by exploring the effect of glacial gravel on vascular plants. Findings indicated that FVC on these glacier forelands generally decreased as the elevation increased or distance from the current glacier terminus decreased. The shady slope (Kekesayi) was more vegetated in comparison to the sunny slope (Jiangmanjiaer) at the glacier basin scale, and the warm and humid deglaciated terrain (Koxkar Baxi) had the highest FVC at the regional scale. Plant family composition and species richness on the glacier forelands decreased with rising elevation, with the exception of those on the Jiangmanjiaer glacier foreland. The relationships between FVC and GC presented negative correlations; particularly, they exhibited variations in power functions on the Kekesayi and Jiangmanjiaer glacier forelands of the eastern Pamir Plateau and a linear function on the Koxkar Baxi glacier foreland of the western Tianshan Mountains. Glacial gravel was found to be conducive to vegetation colonization and development in the early succession stage up until vascular plants adapted to the cold and arid climatic condition, whereas it is unfavorable to the expansion of vascular plants in the later succession stage. These findings suggested that the spatial difference of plant characteristics had close connections with regional climatic and topographic conditions, as well as glacial gravel distribution. In addition, we concluded that aerial photographs can be an asset for studying the functions of micro-environment in vegetation colonization as well as succession on the glacier forelands.     

Vegetation dynamics of coal mining city in an arid desert region of Northwest China from 2000 to 2019

Coal mining has led to serious ecological damages in arid desert region of Northwest China. However, effects of climatic factor and mining activity on vegetation dynamics and plant diversity in this region remain unknown. Wuhai City located in the arid desert region of Northwest China is an industrial city and dominated by coal mining. Based on Landsat data and field investigation in Wuhai City, we analyzed the vegetation dynamics and the relationships with climate factors, coal mining activity and ecological restoration projects from 2000 to 2019. Results showed that vegetation in Wuhai City mostly consisted of desert plants, such as Caragana microphylla, Tetraena mongolica and Achnatherum splendens. And the vegetation fractional coverage(VFC) and greenness rate of change(GRC) showed that vegetation was slightly improved during the study period. Normalized difference vegetation index(NDVI) was positively correlated with annual mean precipitation, relative humidity and annual mean temperature, indicating that these climate factors might play important roles in the improved vegetation. Vegetation coverage and plant diversity around the coal mining area were reduced by coal mining, while the implementation of ecological restoration projects improved the vegetation coverage and plant diversity. Our results suggested that vegetation in the arid desert region was mainly affected by climate factors, and the implementation of ecological restoration projects could mitigate the impacts of coal mining on vegetation and ecological environment.     

生态调控对东亚飞蝗的控制作用研究

东亚飞蝗的成活率,在野生植物中以取食荻和稗者最高,在栽培作物中以取食小麦、玉米最高。生殖力,在野生植物中以取食食狗芽牙根最强,在栽培作物中以取食高粱最强。据此,应用以植被改造为主的生态调控技术,可以形成不利东亚飞蝗的发生、繁衍,而有利天敌繁衍和觅食的生态环境,从而抑制东亚飞蝗的发生。生态控制区在战略上还对飞蝗的迁移起到了隔离作用,但种植棉花、苜蓿、冬枣等不同作物的生态控制区的控蝗效果有一定差异。     

Plant community dynamics in arid lands: the role of desert ants

Ants (Formicidae, Hymenoptera) play an important role in seed bank, seedling establishment andplant composition of arid ecosystems. Thus, knowing plant-ant interaction provides useful information formanagers to design restoration and conservation plans. In this study, the roles of desert harvester ants (Messorintermedius and Messor melancholicus) and scavenger ants (Cataglyphis nodus and Lepisiota semenovi) on plantcommunities were investigated in arid ecosystems of southeastern Iran. Two vegetation types weredistinguished in the study area and the nest density of ant species was determined. Furthermore, plantcomposition and soil seed bank were estimated at different distances from the ant nests. Results showed thatthe density of M. intermedius and M. melancholicus nests was higher in dwarf shrub-shrub vegetation type and thedensity of C. nodus and L. semenovi nests was higher in dwarf shrub vegetation type. The harvester and scavengerants had enhanced the seed bank to 55% and 70%, respectively. Therefore, the role of scavenger ants on theplant communities' seed bank was greater than that of harvester ants. Although the scavenger ants were moreinfluential on the annuals and the invasive plant species, the radius impact of the harvester ants on theperennials was greater, i.e., a positive interaction existed between the perennial plants and the harvester ants. C.nodus and L. semenovi played an important role in enhancing the ecosystem's potential for restoration throughestablishment of pioneer species in early stage of succession. The activity of M. intermedius is crucial for thedevelopment and maintenance of climax plant communities in arid ecosystems through assisting the plantspecies' establishment in late stage of succession. It is essential to preserve the diversity of these key ant speciesfor the maintenance and sustainability of shrubs in arid ecosystems.     

绿洲开发与绿洲荒漠化研究

本文着重讨论了绿洲开发和绿洲内存在的各种荒漠化形式后 ,探讨了绿洲荒漠化的成因以及荒漠化对绿洲生态系统的影响 ,得出 :绿洲荒漠化主要是由于人类不合理的开发引起的 ;荒漠化严重危及绿洲系统的正常运作 ;最后 ,就绿洲景观生态安全格局给出适当的设计 ,希望绿洲内部的人类活动能以保护生态平衡为前提 ,以实现对资源的永续利用     

塔里木河干流景观格局的时空变化分析

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