Flora and ecological characteristics of rare plant communities on the southern slope of Shennongjia Mountain

According to the investigation of sampling area of 6800 m2 on the south slope of Shennongjia Mountain, there were 126 vascular plant species, belonging to 108 genera and 64 families, in the investigated rare plant communities, of which 9 rare plant species were recorded, accounting for 27.3% of the total rare plants. The communities were about 30 m in height and were divided into three layers as tree layer, shrub layer, and herb layer. The flora of the communities had obvious temperate character. Phanerophytes (accounted for 65.9%), Mesophyllous (62.7%), Papyraceous (84.1%), simple leaf (83.3%), un-entire leaf (69.8%) were dominant in life form, leaf size class, leaf texture, leaf form, and leaf margin respectively. According to important value of species, the communities were divided into three types as Davidia involucrata + Litsea pungens community, Cercidiphyllum japanicum + Padus wilsonii community, and Padus wilsonii + Acer mono community. The indexes of species diversity of tree layer had little difference among communities and evenness was high. The results indicated that the communities had complex structure and relative stability.

Distribution pattern of rare plants along riparian zone in Shennongjia Area

Due to the importance of riparian zone in maintaining and protecting regional biodiversity, increasingly more ecologists paid their attentions to riparian zone and had been aware of the important effects of riparian zone in basic study and practical management. In this study, 42 sampling belts (10 m?00 m) parallel to the bank of Xiangxi River at different elevations in Shennongjia Area were selected to investigate the riparian vegetation and rare plants. 14 species of rare plants were found distributing in riparian zone, accounting for 42.4% of the total rare plant species in Shennongjia Area. The main distribution range of the 14 rare plant species was the evergreen and deciduous mixed broadleaved forest at elevation of 1200-1800 m, where, species diversity of plant community was the maximum at the moderate elevation. The analysis of TWINSPAN divided the 14 rare species into 3 groups against the elevation, namely low elevation species group, moderate elevation species group, and high elevation species group. The analysis of DCA ordination showed similar results to that of TWINSPAN. In the paper, the authors discussed the reasons forming the distribution pattern of rare plant species, and pointed out that the important function of riparian zone on rare plant species protection.

Genetic Diversity of Cephalotaxus mannii, a Rare and Endangered Plant

Using RAPD technique, the DNA diversity of Cephalotaxus mannii Hook. f., its genetic diversity pattern, the reasons for its endangered position and conservative approaches were studied. The results show that: 1. The genetic diversity of C. mannii collected from five localities in Hainan is low, and its adaptability to environmental change is weak. 2. The differences of genetic diversity between intra- and inter-populations are great, and the major variation distributes within the population (DNA diversity is 85.1%). 3. The excessive lumbering, man-made destruction, violent typhoon, edible value of the seeds and genetic drift were the main reasons for the low-level genetic diversity of C. mannii and its endangered position. 4. The difference of the micro-environment and other random factors affecting the population should also be taken into full consideration in the study and in protection of such occasionally scattered plants. 5. Enforced measures should be taken to protect the present population, enlarge the population and lower the loss rate of its gene. Mt. Limulin should be chosen as a conservative spot because of its high genetic diversity and less destruction of the forest. Meanwhile, the protection of other populations should be enforced. 6. The differences within and between the populations are great based on different primers used. The change of proportions in polymorphic loci between the populations is more than that between the primers.

Investigation on the Rare and Endangered Plants in the Fenhe Source

Fouty-eight species of rare and endanged plants in the Fenhe Source,belong to 21 families 37 genera.There were 1specie of national second-class protected plant and 3 species of national third-class plants;4 species of first-class protected plants,6 species of second-class protected plants and 14 species of third-class protected plants in Shanxi Province.On the basis of analyzing the endanged reasons,related protection countemeasures were put forward in this article.

Advance of New Researches on Tissue Culture of Rare and Endangered Plant Elaeagnus mollis

This review summarized the recent research achievements on the process of tissue culture of the rare and endangered plant Elaeagnus mollis,including sterilizing protocols of different explants derived from adult plants and seeds for tube germination,two types of plants regeneration（organ type and organ genesis type）,methods of rooting and transplanting,factors affecting culture,as well as browning and vitrification phenomena and avoiding measures.And the further biotechnology research fields of E.mollis were prospected.

Floristic Characteristics of the Rare and Endangered Plants and the Conservation Countermeasures in Tibet, China

The floristic elements and the geographical distribution are analyzed in thispaper based on statistics of elements of rare and endangered plants in Tibet. The results have beengained as following: (1) According to 'the National Important Wild Conservative Plants List (List1)' and 'the National Important Wild Conservative Plants List (List 1)', there are a total of 54plant species (48 genera and 33 families); (2) The geographical elements are very complicated inTibet with 12 of 15 distribution patterns of genera classified by academician Wu; (3) There areobvious temperate genera with 28 genera accounting for 60. 4% of the total genera; (4) There areabundant endemic species accounting for 18. 52% of total species but poor endemic genera; (5) Thegeographical distribution is uneven and a great of species distribute in the areas between 1 000 mand 3 500 m above sea level; (6) To protect the rare and endangered plants efficiently, sixconservation measures are proposed, and 35 species are suggested for the conservative plants of theautonomous conservation level.

Review of Studies on Rare Earth against Plant Disease

Agricultural application of rare earth (RE) has been generalized for several decades, and it is involved in crops, vegetables and stock raising in China. However, all the researches on RE mainly focus on the fields such as plant physiological activity, physiological and biochemical mechanism, sanitation toxicology and environmental security. Plant protection by using RE and the induced resistance of plant against diseases were summarized. The mechanism of rare earth against plant disease is highlighted, which includes following two aspects. First, RE elements can control some phytopathogen directly and reduce its virulence to host plant. Another possibility is that RE elements can affect host plant and induce the plant to produce some resistance to disease.

A review of fractionations of rare earth elements in plants

Studies were carried out on several aspects of rare earth elements （REEs）, such as the theory and practice of their applications in agriculture, their geochemical behaviors in natural and agricultural ecosystems, the mechanisms for the increase of crop yield using REE fertilizer, and their toxicology. However, limited knowledge was available for the transfer processes and the features and mechanisms of distribution and fractionations of REEs inside plants. The characteristics of REE fractionations in plants can be used to ＂trace＂ the pathway of REE transportation from soils （solution） to plants. A better understanding of the mechanisms of REE fractionations was helpful to investigate the controlling factors, including both the internal and the external ones. The characteristics and mechanisms of REE fractionations in plants and their significance were reviewed. Furthermore, the prospect for these fields was discussed, in hope of providing a new way in studying the bioavailability of REEs and heavy metals.

Plants Diversity of the Burigi-Chato National Park: Rare and Invasive Species

This study was conducted within a distance of three to five kilometres around Lake Burigi as a study area in the Burigi-Chato National Park for the purpose of documenting the diversity of plants, identifying invasive and rare species for enhancing conservation in the park. Lake Burigi was purposively sampled as a study area for plant identification due to its potential as a tourist destination. No study has been conducted in the study area to reveal plants diversity, with a focus on documenting invasive and rare species, thus necessitating undertaking of this study to inform the park authority to take urgent control measures in avoiding widespread of invasive species and proper planning for conservation of rare species. The methods involved included field observation;plant identification using field guide books, indigenous and professional knowledge;field mapping using GPS receiver and literature review. Analysis of meteorological data and soil sample were also used among other methods. Meteorological data were analysed using Microsoft Excel and SPSS v.20 to determine the relationship between variables. A total of 102 plant species of different growth forms of trees, shrubs, grasses, sedges, forbs, and herbs were identified and recorded. Tegetes minuta and Argemone mexicana were recorded as invasive plant species, while six rare plant species potential for pharmaceutical industry;Zanthoxylum usambarense, Gardenia ternifolia, Faidherbia albida, Harrisonia abyssinica, Anona senegalensis, and, Pappea capensis were also recorded. Scars of wildfires were observed in the study area. The study area received an average rainfall of 964.36 mm per year, the highest peak recorded in 1951. The trend of rainfall showed that many years had rainfall below the average while the temperature was found to increase from year to year, the situation which suggests the existence of climate change in the study area. There was a weak negative relationship between temperature and wind speed. Soil nutrients and disturbances in the area were found to favour the growth of Tegetes minuta. Findings of this study would help ecological unit in the park to conduct regular ecological assessment for the purpose of controlling invasive plant species, which if left to flourish are likely to reduce habitat suitability for ungulates to utilize the area. Moreover, knowing which plant species are rare, adds value to the area as a destination to visitors interested in plants. The findings also allow the park authority to keep record of species rarity and thus easily take control of them to avoid unintended exploitation. Based on the findings, it was concluded that a number of disturbances, meteorological and edaphic factors favour the growth of invasive species. Urgent measures are to be taken to control the observed invasive plant species before they are left to spread in the park to avoid destruction of the habitat suitability and incurring unnecessary expenses and time in combating them. Furthermore, rare plant species especially those with pharmaceutical and industrial values are to be conserved with special attention to ensure their continued survival. It was recommended that human-induced activities should be prevented through regular ecological assessment, field patrols and public awareness programs. A similar study needs to be conducted during dry season to make comparison of the capacity of plants in adapting to different changes of the weather.

Zhujiang Refinery The Largest Rare Earth Plant in South China

Zhujiang Refinery is located in the east suburb of Guangzhou city, the People’s Republic of China. Thegeographical advantage makes it convenient both in communications and in foreign trade. The refinery cov-ers an area of 15 hectares and has nearly 1000 staff members, more than 200 of whom are engineering andtechnical personnel. Established in 1966, Zhujiang Refinery has engaged in the production and scientific re-search of rare earths for more than 20 years. Having fixed assets of about RMB 20 million yuan, ZhujiangRefinery is the largest base for producing and exporting rare earths in the south of China.

Advances on Rare Earth Application in Pollution Ecology

The use of rare earth for inducing plant resistance was reviewed. The important developments in recent years were described, and rare earth can alleviate the pollution of acid rain, ozone, pesticide, heavy metals etc. in environment. The authors suggest that the mechanism of rare earth to inducing plant resistance and reducing plant injury is to control biochemical metabolism web in plant cell, to adjust its protection system of free radical, to maintain its photosynthesis, to protect cell membrane system and to carry through its function on mineral metabolism. Meanwhile some problems in the field were discussed as well.

Application of Rare Earth Phosphate Fertilizer in Western Area of China

Rare earth phosphate fertilizer (REPF) as base fertilizer (750 kg per hm2) was applied in the western area of China during the 'Tenth Five-Year Plan' , and the results show as follows: compared with calcium superphosphate (CK), REPF increases crops yields for maize by 17.0% , for rice by 10.5% , for wheat by 24.2% , for potato by 18.5% , for cabbage by 16.3%, for Chinese cabbage by 16.4%, for beet by 6.5%; decreases the diseased plant rate for common smut of maize by 1.0%, for maize stalk rot by 1.2%, for wheat take-all disease by 7.8%, for wheat root rot by 3.2%, for potato blackleg disease by 1.4%, for potato late blight by 6.6%; increases the sugar content of beet by 0.9°S.

Distribution and Current State of Rare and Endangered Tulips (Liliaceae) Arid Zones of Uzbekistan

Central Asia is considered to be the primary center of origin and diversity for the genus Tulipa L. (Liliaceae). The article considers the species of rare and endemic Tulipa L. species in the arid regions of Uzbekistan. There are nine registered species of the genus Tulipa. In the course of the study, the demographic indicators of the modern population of 39 populations were evaluated. 39 populations of the studied species were identified, most of which grow in the composition of the wormwood formations characteristic of the Turanian floristic province.

Distribution of Vascular Plants along Altitudinal Gradients in Hoang Lien National Park, Vietnam

The present study was conducted to examine the distributional characteristics of floral communities along the altitudinal gradients in Hoang Lien National Park (HLNP), located in Lao Cai province, Vietnam. We recorded the relatively abundant flora system with 3252 species (including 361 endemic species and 237 endangered species), belonging to 1126 genera, 230 families and 6 different phyla. Methodology of sampling, specimen collection and identification, statistical analysis are simultaneously used for investigating the complex changes of composition and richness of plant assemblages. The study results indicated the divisions in quantity and composition, especially differentiation of endemic and rare species in accordance with altitudinal gradients.

杭州西湖风景名胜区陆生维管植物物种多样性现状与分析

2020年至2022年对杭州西湖风景名胜区内的陆生维管植物进行了调查。通过对历史文献的收集和对本次调查结果的评析,共记录陆生维管植物1223种(含种下单位),隶属156科,610属。记录区域内新增野生或逸生植物15种,并对65种植物在区域内的现存提出质疑;同时对物种的科属组成、生活型组成、珍稀濒危植物现状及外来植物进行了分析;本次调查到珍稀植物14种,记录具潜在风险的外来植物34种,其中新增7种;最后对景区的植物多样性保护提出了合理建议。

六盘山濒危稀有药用植物资源及保护等级评价

目的:六盘山蕴藏着丰富的濒危稀有药用植物资源。对六盘山濒危稀有药用植物进行调查,明确濒危稀有药用植物优先保护等级,为合理保护提供依据。方法:采用野外路线调查、样方调查和文献调研,并利用7项濒危植物优先保护等级评价指标,确定六盘山濒危稀有物种优先保护序列。结果:六盘山分布有濒危稀有药用植物25科39属53种,一级保护的药用植物有4种,二级保护的药用植物有7种,三级保护的药用植物有42种。濒危稀有药用植物自身的生物学特性和人为过度干扰是其致濒危的主要原因。结论:六盘山珍稀濒危药用植物亟待保护,建议按照保护等级因地制宜开展保护工作。

峨眉山珍稀濒危种子植物多样性及区系分析

为研究峨眉山及周边山区珍稀濒危种子植物的多样性,项目组通过多年野外样线及样方调查,对该区域的珍稀濒危植物种类、珍稀濒危种子植物科、属的区系成分及特点进行调查和分析。结果表明:(1)峨眉山及周边山区共有185种珍稀濒危种子植物,归于36科98属;被子植物占绝对优势,有30科84属169种,裸子植物有6科14属16种。被《国家重点保护野生植物名录》收录的有78种,其中国家一级重点保护野生植物有8种;被《全国极小种群野生植物拯救保护工程规划》收录的有7种。(2)峨眉山及周边山区珍稀濒危种子植物的区系成分与该地区蕨类、裸子植物和被子植物的科、属地理分布区系成分基本一致,即温带成分和热带成分都比较丰富(温带成分略占优势),两种成分交汇融合,表现出热带、亚热带向温带过渡的特点。

Biological Function of REE in Plants & Microbes

Rare earth elements （REE） and their compounds years. The bioinorganic chemical research of REE during the are widely applied in agronomic and medical fields for many past few years indicates that REE play important roles in the promotion of photosynthetic rate as well as root absorption, regulation of hormone and nitrogen metabolism, and suppression of microbes, etc. The metallic or non-metallic targets of key biomolecule in various physiological processes can be chosen by REE for the chelation or replacement, which enables REE to regulate the biological functions or behaviors of those biomolecule and consequently leads to significant embodiment of biological function of REE in plants and microbes. Overdose of REE, however, shows an inhibitory effect on living organisms. Therefore, this paper proposes two suggestions that will be available in the extension of full use of REE＇s biological function. One is to obey the dose law of REE and control REE concentrations within a safe range. The other is to further test the bioaccumulation and long-period influence of REE on organisms.

蒜头果幼苗衰退过程中组织养分含量变化特征

在没有寄主植物存在的情况下,蒜头果幼苗长势随独立生长时间延长而逐渐衰退是一种普遍现象。为解析蒜头果幼苗衰退过程中组织养分含量变化和分布特征,该研究比较了独立生长半年、两年和三年的蒜头果植株各部分组织中N、P、K元素浓度变化,并用组织切片染色法定性评估了这些不同衰退程度幼苗的根和茎杆中淀粉分布和含量变化。结果表明:(1)蒜头果幼苗在衰退过程中,除侧根中K浓度逐渐升高外,其余器官中组织N、P、K浓度逐渐降低,叶片N/P比逐渐失衡,衰退程度不同的幼苗所受的养分胁迫类型存在差异,其中独立生长半年的蒜头果幼苗主要受N供应不足的限制(平均N/P比11.33),两年后转为P限制(平均N/P比17.81),三年后蒜头果幼苗叶片N/P比严重失衡(均值52.46),活力极低,不适合用于造林。(2)植株淀粉含量水平逐渐降低,独立生长三年后蒜头果幼苗植株中淀粉消耗殆尽。幼苗茎根交界处、根顶膨大处、主根及侧根的淀粉含量水平在不同衰退程度的幼苗间差异均较显著,表明淀粉含量水平可以作为评估幼苗活力的重要参考,其中侧根可以作为微创法检测幼苗活力的理想取样部位。鉴于独立生长的蒜头果幼苗活力逐渐衰退与组织养分含量降低有关,在蒜头果育苗过程中应合理补给矿质元素、配植优良寄主植物并尽早移栽,以免因幼苗活力衰退而导致造林成活率降低。该研究结果为寻找评估蒜头果幼苗活力的方法提供了理论参考和技术借鉴,并为育苗过程中合理施肥提供了科学指导。

珍稀濒危植物江南油杉群落区系与种群动态分析

江南油杉为国家二级重点保护野生植物,以福建君子峰国家级自然保护区江南油杉群落为对象,通过样地调查和数据统计,分析物种组成及植物区系成分,编绘静态生命表、存活曲线和生存函数曲线,计算数量动态指数,并引用时间序列模型,以探明江南油杉群落现状及种群动态,为该物种保护提供理论依据。结果表明,1)该群落有维管束植物54科97属159种,划分为10个分布区类型和10个亚型,热/温比值(R/T)为1.81。2)种群年龄结构呈“金字塔”形结构,第Ⅶ龄级个体缺失,总体呈现“增长-稳定-衰退-增长-衰退”的波动结构动态关系。3)种群存活曲线属于“凹”形(Deevey-Ⅲ型),死亡率和消失率最大值均出现在第Ⅰ龄级,最小值均出现在第Ⅲ龄级。4)种群生存率逐渐下降,累计死亡率逐渐增加,死亡密度和死亡率的变化趋势从第Ⅱ龄级后基本表现一致,均在第Ⅲ龄级出现最小值,之后变化基本持平。5)时间序列模型显示,种群将以小树和中树为主,老年个体的数量波动不大。综上所述,江南油杉种群发展稳定性不高,幼苗死亡率高(94.1%),种群规模呈逐渐缩小趋势,需通过开展科学的人工措施,适当疏伐,创造林窗,改善林内生存环境,从而促进幼苗生长。