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Table of Content
    Volume 13 Issue 4
    20 July 2005

    Solidago canadensis (Compositae), Canada goldenrod, is a long-lived perennial plant native to North America. It was initially introduced as an ornamental plant to Shanghai in 1935, but then escaped into the wild. It has become an invasive exotic weed spreading rapidly in China, especially eastern China, where it can be found in arable fields, riparian zones, roadsides, wastelands, and courtyards. The photo taken in October 2004 shows the monocultures of S. canadensis on a roa

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    Species richness and vertical distribution pattern of flea fauna in Heng-duan Mountains of western Yunnan, China
    Zhengda Gong, Houyong Wu, Xingde Duan, Xiguang Feng, Yunzhi Zhang, Quan Liu
    Biodiv Sci. 2005, 13 (4):  279-289.  doi:10.1360/biodiv.040177
    Abstract ( 3977 )   PDF (376KB) ( 3657 )   Save
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    The field investigation data from 18 hilly areas in Hengduan Mountains of western Yunnan, China were accumulated and statistically analyzed in order to understand the basic distribution of the species richness and fauna pattern of fleas along altitudinal gradients, and ecological factors affecting their distribution. The altitude of areas investigated ranged from 1000 to 5000 m, and 142 species, 43 genera and 9 families of fleas were recorded. The analysis revealed that: (1) the genus richness, species richness, endemic species richness, ratios of endemic species and the species richness of different faunal realms gradually increased and then decreased with increase of elevation, such that a single-peak curve appears in vertical distribution. The peak appeared in the areas from 2500 m to 3800 m above sea level; (2) the vertical distribution pattern of Oriental fauna was quite different from that of Palaearctic fauna. The species components of Oriental fauna gradually decreased along the altitudinal gradient while those of Palaearctic fauna showed an increasing tendency, which reflected a pattern similar to that of the vertical distribution along the latitudinal gradient; (3)flea species in 9 vertical zones of Hengduan Mountains were classified into 6 ecological types by cluster analysis, which reflected the influence of some ecological factors (such as altitude, climate, and vegetation) on flea species distribution and community composition. It also demonstrated that flea distribution is in ac-cordance with the altitudinal gradient and environment. (4) A two-peak curve appeared in the vertical distri-bution of β diversity along an altitudinal gradient, which revealed a transitional fluctuation of flea species composition and distribution among the differential elevation, climate and vegetation zones. Both the bound-ary effect of transitional fauna or flora and the humidity may be the main reasons for the peak of species richness, genus richness and family richness in the middle elevation zones (2500-3800 m). We conclude that the pattern of flea distribution along an altitudinal gradient may be affected by a variety of factors, including altitude, the boundary effect of transitional fauna or flora, rainfall, climate, habitat, human ac-tivities, etc.

    Reproductive modes in Sichuan anurans
    Cheng Li, Qiang Dai, Yuezhao Wang, Haijun Gu, Zhijun Liu
    Biodiv Sci. 2005, 13 (4):  290-297.  doi:10.1360/biodiv.050029
    Abstract ( 2838 )   PDF (88KB) ( 3143 )   Save
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    A total of 94 anuran species have been recorded in Sichuan Province, China. Among these species, there are five different reproductive modes belonging to two major categories according to Duellman & Trueb’s (1986) definition. The most common (93%, 68 of 73 species) site type of oviposition is free moving water, including both lentic water (mode 1) and lotic water (mode 2), which have been considered to be the primitive modes of reproduction in anurans. The deposition of eggs out of water includes terrestrial nests near water (mode 12), terrestrial foam nests in burrows or depressions (mode 21), and arboreal foam nests on trees and bushes over ponds or streams (mode 23). Species using modes 1, 12, 21, and 23 have smaller body sizes and deposit larger clutch sizes with smaller ovum diameter than those species using mode 2. Tadpoles of the former species inhabit non-flowing water systems and develop quickly; these tadpoles have small body sizes and short tails. Species using mode 2 have large body size, produce small clutch sizes with large ovum diameter. Their tadpoles inhabit flowing water systems and require a long development time; these tadpoles have large body size and long tails. The species using mode 1 exhibit a r-selected strategy by producing small-yolked eggs, investing less energy in each egg, and increasing clutch size. Conversely, the species us-ing mode 2 produce large-yolked eggs, invest more energy per egg, and show a reduction in the number of eggs, which is characteristic of a k-selected strategist.

    A large-scale pattern in species diversity of reptiles in the Yangtze River Basin
    Xiaodong Yu, Tianhong Luo, Qiang Dai, Yuming Wu, Hongzhang Zhou
    Biodiv Sci. 2005, 13 (4):  298-314.  doi:10.1360/biodiv.050064
    Abstract ( 3228 )   PDF (610KB) ( 4070 )   Save
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    We synthesized information on reptile biodiversity in the Yangtze River Basin. We documented 166 species that had been recorded and described from the basin. There are 3 orders, 18 families and 68 genera. Of these, 24 species are endemic and 54 endangered. Since the distribution patterns of terrestrial reptiles are determined by the deep rivers and high mountains to a great extent, we divided the Yangtze River Basin into 19 sub-regions. Except the headwater of the basin, the other 18 sub-regions show similar values in species richness and G-F index. However, the proportion of endemic species decreased gradually from the headwater to the estuary of the basin with the gradient of elevation. Based on the species distribution in 19 sub-regions (Jaccard similarity), cluster analysis was used to analyze the similarity of reptiles in the 19 sub-regions. The 19 sub-regions were clustered into five groups: (1) The headwaters of the basin, (2) Hengduan Mountains and Yunnan Plateau, (3) Sichuan Basin and Qinling-Dabashan Mountains, (4) Guizhou Plateau, Jiangnan hills, the Two-Lake Plain and the delta of the Yangtze River Basin, (5) Poyang Lake Plain, lower reaches of the basin, and Huaiyang Mountains (from Hanjiang River to Dabieshan Mountain). This grouping reflects the environmental characteristics of the total basin and the three large topographic platforms of the Chinese mainland.

    Phylogenetics of the common pearl oysters in the genus Pinctada: evi-dence from nrDNA ITS sequence
    Da Hui Yu, Ka Hou Chu
    Biodiv Sci. 2005, 13 (4):  315-323.  doi:10.1360/biodiv.050050
    Abstract ( 2859 )   PDF (373KB) ( 3029 )   Save
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    Some species in the genus Pinctada are important resources for the pearl industry, but some of them are on the verge of extinction. We studied the evolutionary relationship and identification of some species in Pinctada based on sequences of the internal transcribed spacers (ITS1 and ITS2) of nuclear ribosomal DNA. The length of ITS1 ranges from 410 to 482 bp, with P. margaritifera and P. maxima being the longest, and P. fucata, P. fucata martensii, P. imbricata and P. nigra the shortest. The length of ITS2 ranges from 210 to 249 bp, with P. albina and P. nigra being the longest, and P. margaritifera and P. maxima the shortest. Homogeneity test on the pattern of nucleotide substitution indicates that the GC contents in P. margaritifera and P. maxima are significantly higher, and chromosomal rearrangements may have occurred in P. chemnitzi. This finding suggests that P. margaritifera and P. maxima are likely to be primitive species and P. chemnitzi appears to be a recent species. Phylogenetic analysis shows that the pearl oysters studied constitute three clades: clade I with P. fucata, P. fucata martensii and P. imbricata, clade II with P. albina, P. nigra, P. chemnitzi and P. radiata, and clade III with P. margaritifera and P. maxima. The insignificant genetic dif-ferentiation among the species in clade I indicates that they may be conspecific, with P. imbricata being the senior synonym. In clade II, the low genetic divergence between P. albina and P. nigra suggests that they may represent two subspecies. The ITS1 sequence of P. radiata in GenBank is almost identical to that of P. chemnitzi as determined in the present study, and thus we suspect that the specimen used for the P. radiatasequence in GenBank was misidentified. Clade III has a basal position , suggesting that species in this clade are more primitive than the others. This is congruent with the results revealed by the homogeneity test on the nucleotide substitution pattern.

    Genetic structure of Cryptocarya chinensis in fragmented lower sub-tropical forests in China based on ISSR markers
    Zhengfeng Wang, Sanhong Gao, Shengni Tian, Shenglei Fu, Hai Ren, Shaolin Peng
    Biodiv Sci. 2005, 13 (4):  324-331.  doi:10.1360/biodiv.050055
    Abstract ( 3084 )   PDF (177KB) ( 2806 )   Save
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    Forest fragmentation is the main threat to global biodiversity. However, genetic information concerning the effects of fragmentation is currently lacking for plant species in lower subtropical China. To enrich scientific understanding of this issue, we employed the ISSR (inter-simple sequence repeat) markers to determine the genetic structure in Cryptocarya chinensis. Four hundred and forty-eight individuals from six fragmented populations in Guangdong Province were sampled according to age classes. Four of these populations, DHS, HSD, DWL and GT, were in nature reserves, and the other two, LG and RP, were near villages. Seven ISSR primers produced a total of 209 polymorphic bands which were used to evaluate genetic variation. The results showed that C. chinensis displayed unexpectedly low genetic variation within populations (HP =0.0537) and high genetic differentiation among populations (GST=0.6489, φST=0.6797). Genetic variations in LG (0.0251) and RP (0.0000) populations were lower than in the other four well-conserved populations. Considering age classes, low but significant genetic differentiation characterized DHS and HSD populations. These results indicate that C. chinensis has experienced a recent decrease in population size which may cause a bottleneck effect. The resulting fragmentation increased genetic drift and inbreeding, causing theloss of genetic variation. Our results for C. chinensis may be general for other species in this area and there-fore more work related to conservation is urgently needed.

    Effects of density on seedling survival and growth of an endangered species Myricaria laxiflora
    Fangqing Chen, Gaoming Xiong, Zongqiang Xie
    Biodiv Sci. 2005, 13 (4):  332-338.  doi:10.1360/biodiv.050037
    Abstract ( 2807 )   PDF (221KB) ( 2590 )   Save
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    Myricaria laxiflora, distributed along the riverside of the Yangtze River in the Three Gorges area, lost its habitats and became an endangered species in 2003 due to the water storage of the Three Gorges Project. In order to understand whether density plays an important role in population self-modulation, we conducted an outdoor experiment which included five density treatments in the Center for Ecological and Environmental Research of China Three Gorges University. The changes of seedling death, below-ground seedling biomass, above-ground seedling biomass, total seedling biomass, number of branches, root depth, and length of first grade branch in different density treatments were examined in our experiment. The results showed that seedling survival rate decreased with increase of seedling density, and was reduced significantly when seedling density was greater than 250 ind./m2. Total seedling biomass, above-ground seedling biomass and below-ground seedling biomass differed noticably between density treatments. The correlation coefficient between above-ground biomass and density was bigger than that between below-ground biomass and density. Also, the number of branches, root depth and length of first grade branch decreased significantly with in-creases of seedling density, but number of branches responded more sensitively to density than length of branch and root depth. These results indicated that seedling density significantly stressed seedling survival and growth in Myricaria laxiflora, especially the growth of above-ground parts, and that density played an important role in population self-modulation and stability maintenance. The relationship of total biomass and below-ground biomass with other parts of seedlings were also explored with regression to understand theimpact of density on the growth of different parts of seedlings and to find proper density for population re-construction and management. We suggest that the density of 250 ind./m2 was the limit for population recon-struction.

    Geographic distribution and current status of the endangered genera Sinojackia and Changiostyrax
    Xiaohong Yao, Qigang Ye, Ming Kang, Hongwen Huang
    Biodiv Sci. 2005, 13 (4):  339-346.  doi:10.1360/biodiv.050059
    Abstract ( 3252 )   PDF (358KB) ( 3470 )   Save
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    The genera Sinojackia and Changiostyrax (Styracaceae) including only seven species native to China are currently in the endangered status due to intensive human disturbances. We conducted an extensive field survey of their current native geographic distributions, and in situ and ex situ conservation status of the remnant populations. The results showed that in spite of a wide range of natural distribution of Sinojackia, most species in the genus maintained a small number of populations with very small population size, appar-ently resulting from habitat degradation and population losses. S. xylocarpa and S. rehderiana were extinct in Jiangshu Province where the type specimen was collected. During the survey, S. xylocarpa was rarely found in Shangcheng and Xinxian counties of Henan Province, and Guangshui and Changyang counties of Hubei Province. In addition, S.rehderiana was aslo extinct in the type specimen site in Nanchang, Jiangxi Province. In past nearly 70 years, neither wild populations nor individuals of S. henryi were found since the type specimen was first identified in 1937, suggesting this species may be either a synonym mixed with other Sinojackia species or extinct in the wild. The populations of S. microcarpa were reduced rapidly in wild be-cause of anthropogenic destruction and only two sizeable populations were located in Zhejiang Province. S. sarcocarpa and S. oblongicarpa had only one population survived in Leshan and Huaihua, respectively, which suggested critically endangered in wild. A possible new taxon was found during the field survey andneeds for further taxonomic identification. Most species investigated had small number of populations and low seedling recruitment within each population because of low rate of seed germination. The deforestation by local residents had great impact on the survival of Sinojackia and Changiostyrax. Therefore, an integrat-ing conservation strategy should be urgently carried out and current in situ and ex situ conservation be rigidly forced in order to conserve the two endangered genera. We also suggest that all seven species should be in-cluded in the national endangered species list.

    Impact of invasive species on soil properties: Canadian goldenrod (Soli-dago canadensis) as a case study
    Jianzhong Lu, Wei Qiu, Jiakuan Chen, Bo Li
    Biodiv Sci. 2005, 13 (4):  347-356.  doi:10.1360/biodiv.050071
    Abstract ( 2557 )   PDF (284KB) ( 4153 )   Save
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    Invasive alien species (IAS) may threaten native biodiversity and cause considerable economic loss, so more and more attention has been directed towards the assessment of the impact of IAS on native ecosystems. Here, the effects of invasive Canadian goldenrod (Solidago canadensis) on soil properties were examined both in common gardens and under natural conditions. In the common garden experiment, S. canadensis and Chinese goldenrod (S. decurrens) were grown together. After a growing season, soil properties were measured, including pH, pools of soil nitrogen (N), carbon (C), organic matters (SOM) and extractable inorganic nitrogen (NH4-N and NO3-N), and fluxes of net mineralization rate (MIN), net ammonification rate (AMO) and net nitrification rate (NIT). Similar variables representing soil properties were also measured in a field infested with S. canadensis. Our results show that the effects of S. canadensis invasions on soil properties observed in common gardens were similar to those under natural conditions. The invasion of S. canadensis increased the pools of N, C and SOM, but reduced the NH4-N and NO3-N; and S. canadensis also changed soil pH to ca. 8.2 in both garden and field experiments. However, the magnitude of change in several soil properties was larger in field experiments than in garden experiments, which might be the result of the difference in invasion time. C and N contents were only 10% higher in soil planted with S. canadensis than in the soil without S. canadensis in the garden experiments. In contrast, C and N contents were 100% higher in the soil colonized by S. canadensis than in the soil without S. canadensis in the field experiments. Similarly, SOM and NH4-N in the soil showed considerable difference between garden and field experiments. No significant difference in NO3-N was detected, either in garden or field experiments. Interms of fluxes, MIN increased by 3 times when the field was invaded by S. canadensis, indicating that S. canadensis invasions increased the inorganic nitrogen supply. Independent fertilization experiments controlling inorganic nitrogen form and total nitrogen concentration suggest that S. canadensis grew better at a higher ratio of NH4-N to NO3-N or at higher nitrogen levels. This study provided experimental data both for assessment of impacts of plant invaders on soil and for exploration of the mechanism of their successful invasions.

    Ant biodiversity in different habitats in Shilin Park, Yunnan Province
    Zhiying Zhang, Yuhui Li, Dongmei Chai, Liang Zhang
    Biodiv Sci. 2005, 13 (4):  357-362.  doi:10.1360/biodiv.040173
    Abstract ( 2870 )   PDF (409KB) ( 3290 )   Save
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    During May (beginning of rainy season) and September (late rainy season) of 2003, we collected ants by trapping in five karst habitats in Shilin Park, Yunnan: Cyclobalanopsis glaucoides forest representing the original subtropical karst plateau monsoon zonal vegetation, secondary forest, brush, grassland, and Pinus yunnanensis forest representing the secondary-succession karst vegetation. The community composition and diversity of ants, and community similarity were studied, and cluster analysis was conducted. All 8775 ants from the five habitats were grouped into 4 subfamilies, 16 genera and 26 species. The dominant species are Kartidris ashima, Pseudolasius bournica, and Campontus chongqingensis. The lowest diversity index was found in the Cyclobalanopsis glaucoides forest, and the highest in brush and the Pinus yunnanensis forest. The similarity index of all communities fell between 0–0.2609. The results showed that ant diversity was affected by environmental factors, and significant differences occurred among ant communities in secondary habitats in karst zonal vegetation created by human disturbance.

    Meta-property right, derived property right and right of modification of biogenetic resources
    Zhigang Jiang
    Biodiv Sci. 2005, 13 (4):  363-366.  doi:10.1360/biodiv.050084
    Abstract ( 2800 )   PDF (168KB) ( 2654 )   Save
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    I explored the ownership of biogenetic resources and put forward the concepts of meta-property right, property right and rights of modification of genetic resources. Meta-property right is the property right over the carrier of genetic resources— the animal and plant body, its gametes and genetic information. Derived property right is the partial right of the meta-property right owner of a genetic resource which has been genetically modified for commercial purposes. Much confusion in the acquisition and benefits sharing of genetic resources(ABS)are due to failure to define meta-property right and derived property right; We should pay attention to such problems. Any modification of genetic resource should obey the principle of “respect-ing life”, which matches with the statement “realizing the intrinsic value of biological diversity” of the Con-vention on Biological Diversity. Intrinsic value of biological diversity includes the survival value of species and its extension, the survival value of individuals of the species. Right of modification of the human genetic resource is to be decided by the majority of human society or the state. Modification right of genetic resource should be practiced according to the principles of “preservation”, “good-will” and “preventing ill-doing”. Modification of genetic resource should improve the well-being of human, such as increasing production of crops, reducing contents of harmful material, enhancing the disease resistance of crop and livestock, or bene-fit the environmental protection. Any modification of genetic resource should prevent such ill-will modifica-tion which harms the stabilization of genetic structure of human and wildlife, or creates a new harmful or-ganism.

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