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.

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.

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.

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.

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.

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.

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.

Adaptive introductions:How multiple experiments and comparisons to wild populations provide insights into requirements for long-term introduction success of an endangered shrub

Recovery of an imperiled plant species may require augmentation of existing populations or creation of new ones.Hundreds of such projects have been conducted over the last few decades,but there is a bias in the literature favoring successes over failures.In this paper,we evaluate a series of introductions that experimentally manipulated microhabitat and fire in an adaptive introduction framework.Between 2002 and 2012,we(and our collaborators) carried out ten introductions and augmentations of Florida ziziphus Pseudoziziphus(Condalia,Ziziphus) celata,a clonal shrub limited to very small populations and narrowly endemic to pyrogenic central Florida sandhills.Six of the introductions were designed as experiments to test hypotheses about how demographic performance was affected by microhabitat,fire,and propagule type.Introduced transplants had high survival(<90%annually),inconsistent growth,and little transition to reproduction,while introduced seeds had low germination and survival.Transplants were more efficient than seeds as translocation propagules.Shaded(vs.open) sites supported generally higher transplant and seedling survival and seed germination percentages,but growth responses varied among experiments.Supplemental irrigation increased transplant survival and seed germination,but otherwise seedling and plant survival and growth were not significantly affected.Contrary to expectations based on wild populations,introduced propagules have not been more successful in unshaded sites,suggesting that Florida ziziphus has broader microhabitat preferences than hypothesized.Compared to wild plants,introduced plants had similar survival and responses to fire,slower growth,and more delayed flowering.Introduced plants had no clonal spread.While no introduced population has demonstrated a capacity for long-term viability,one augmented population has flowered and produced viable fruits.Given that Florida ziziphus genets are long-lived,low levels of sexual reproduction may be adequate for the establishment of viable populations.Thus,after many translocations over more than a decade,it is premature to characterize any single translocation as a success or a failure,underscoring the need for a long view of translocation success.

Assessment of the State of <i>Onobrychis tavernierfolia</i>Stocks ex Boiss.(Fabaceae) Cenopopulations Southwestern Kyzylkum(Uzbekistan)

In the period 2019-2021, two coenotic populations of O. tavernierfolia were studied in different ecological and phytocenotic conditions of relic mountain Kuldzhuktau. Very rare species of the Kyzylkum. It is spread at the Kyzylkum: the Kuldzhuktau, near Ayak-Guzhumdy and Churuk (Bukhara region). Inhabits stony and gypseous slopes. There are three small populations can be found. Limiting factors: degradation of habitat as a result of overgrazing. Measures of protection: not protected. The article is devoted to the assessment of the current state of coenotic populations of the rarest southwestern Kyzylkum (Kuldzhuktau) Onobrychis tavernierfolia. It was found that the studied coenopopulations of O. tavernierfolia are normal and complete.