Relationship of species diversity between overstory trees and understory herbs along the environmental gradients in the Tianshan Wild Fruit Forests, Northwest China

With the intensification of desertification in northwest China, drought has become a serious environmental problem restricting plant growth and ecological restoration. Recently, dark septate endophytes (DSEs) have attracted more attention because of their ability to improve plants’ resistance to drought. Here, we investigated DSE colonization and species diversity in roots of Lycium ruthenicum collected from Anxi and Minqin, in northwest China, during July, September, and December 2019. This study aimed to evaluate the influence of seasonality and sampling sites on DSEs. In different seasons, DSE colonization varied with the phenology of L. ruthenicum. At different sites, DSE colonization significantly differed. Four isolates were reported in desert ecosystems for the first time. The results showed microsclerotial colonization was directly affected by changing seasons, while hyphal colonization and species diversity were directly affected by sampling sites. The soil organic carbon, pH, alkaline phosphatase, and alkali-hydrolyzable nitrogen were the main predictors of DSE colonization and species diversity. We conclude that DSE colonization and diversity showed significant spatial–temporal heterogeneity and were closely related to soil factors. This research provides a basis for the further understanding of the ecological functions of DSEs and their application potential for vegetative restoration and agricultural cultivation in drylands.

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Stand structure and height-diameter relationship of a degraded Populus euphratica forest in the lower reaches of the Tarim River, Northwest China

Journal of Arid Land ◽

10.1007/s40333-015-0046-8 ◽

2015 ◽

Vol 7 (4) ◽

pp. 544-554 ◽

Cited By ~ 8

Author(s):

Tayierjiang Aishan ◽

Ümüt Halik ◽

Florian Betz ◽

Tashpolat Tiyip ◽

Jianli Ding ◽

...

Keyword(s):

Stand Structure ◽

Populus Euphratica ◽

Northwest China ◽

Tarim River ◽

The Tarim River ◽

Relationship Of

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Vine species diversity across environmental gradients in northwestern México

Biodiversity and Conservation ◽

10.1023/b:bioc.0000035871.80725.1a ◽

2004 ◽

Vol 13 (10) ◽

pp. 1853-1874 ◽

Cited By ~ 22

Author(s):

Francisco Molina-Freaner ◽

Reyna Castillo Gámez ◽

Clara Tinoco-Ojanguren ◽

Alejandro E. Castellanos V.

Keyword(s):

Species Diversity ◽

Environmental Gradients ◽

Northwestern Mexico

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Species diversity of insects on the Ordos Plateau, Northwest China

Biodiversity Science ◽

10.17520/biods.2001049 ◽

2001 ◽

Vol 09 (4) ◽

pp. 329-335

Author(s):

ZHOU Hong-Zhang ◽

LUO Tian-HOng ◽

YU Xiao-Dong ◽

Keyword(s):

Species Diversity ◽

Northwest China ◽

Ordos Plateau

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Plant Community Analysis along Environmental Gradients in Moist Afromontane Forest of Gerba Dima, South-western Ethiopia

10.21203/rs.3.rs-19997/v1 ◽

2020 ◽

Author(s):

Abyot Dibaba Hundie ◽

Teshome Soromessa Urgessa ◽

Bikila Warkineh Dullo

Keyword(s):

Cluster Analysis ◽

Species Diversity ◽

Plant Species ◽

Plant Community ◽

Plant Communities ◽

Environmental Gradients ◽

Floristic Composition ◽

Regional Government ◽

Community Types ◽

Western Ethiopia

Abstract Background This study was carried out in Gerba Dima Forest, South-Western Ethiopia, to determine the floristic composition, species diversity and community types along environmental gradients. Ninety sample plots having a size of 25 × 25 m (625 m2) were laid by employing stratified random sampling. Nested plots were used to sample plants of different sizes and different environmental variables. All woody plant species with Diameter at breast height (DBH) ≥ 2.5 cm and height ≥ 1.5 m were recorded in 25 m X 25 m plots. Within the major plots, five 3 m x 3 m subplots (9 m2) was used to collect shrubs with dbh < 2.5 cm and > 1.5 m height. Within each 9 m2subplots, two 1 m2 subplots were used to collect data on the species and abundance of herbaceous plants. Hierarchical (agglomerative) cluster analysis was performed using the free statistical software R version 3.6.1 using package cluster to classify the vegetation into plant community types. Redundancy Analysis (RDA) ordination was used in describing the pattern of plant communities along an environmental gradient. Result One hundred and eighty plant species belonging to 145 genera, 69 families and comprising of 15 endemic species were recorded. Cluster analysis resulted in five different plant communities and this result was supported by the ordination result. RDA result showed altitude was the main environmental variable in determining the plant communities. The ANOVA test indicated that the five community types differ significantly from each other with regard to EC and K. Conclusions The studied forest can play a significant role in biodiversity conservation since it harbours high species diversity and richness. Thus, all Stakeholders including Oromia Forest and wildlife enterprise (OFWE) and the regional government should work to designate the forest as a biosphere reserve and being registered under UNESCO.

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Late Quaternary Ostracode From a Core in the Weddel Sea, Antartica

Pesquisas em Geociências ◽

10.22456/1807-9806.21130 ◽

1999 ◽

Vol 26 (1) ◽

pp. 11 ◽

Cited By ~ 2

Author(s):

ROBIN WHATLEY ◽

RAYMOND ROBERTS

Keyword(s):

Species Diversity ◽

North Atlantic ◽

Late Quaternary ◽

Weddell Sea ◽

The Core ◽

Constituent Species ◽

Low Diversity ◽

Relationship Of ◽

The Antarctic ◽

The Relationship

Fifty-nine samples from a 560cm gravity core of late Quaternary age (PS1003-2), collected at a depth of 2796m in the Weddell Sea, were examined for Ostracoda. The fauna was sparse but, from a total of 556 valves, the rather low diversity fauna of 19 species belonging to 11 genera and 3 families was identified. The study is principally concerned with species diversity, originations and extinctions, inter-relationships between species and the relationship of the fauna to different water masses. With respect to species diversity and origination/extinction patterns, two distinct phases are apparent: an initial diversification (originations only), followed by a phase of overall stable diversity (originations approximately matched by extinctions). The ostracod fauna is closely comparable to that described by authors as typical of North Atlantic Deep Water but is actually from the Antarctic Bottom Water (AABW). Two of the principal constituent species Henryhowella dasyderma (Brady) and H. asperrima (Ruess) seem to be mutually exclusive within the core. Changes in the fauna through the core seem to be related to climatic cycles.

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Batrachospermales (Rhodophyta) of China: a catalogue and bibliography

Nova Hedwigia ◽

10.1127/nova_hedwigia/2020/0565 ◽

2020 ◽

Vol 110 (1) ◽

pp. 37-77

Author(s):

Shulian Xie ◽

Mingyu Qiu ◽

Fangru Nan ◽

Kunpeng Fang ◽

Jinfen Han

Keyword(s):

Phylogenetic Analysis ◽

Morphological Characteristics ◽

Northwest China ◽

Molecular Data ◽

Central China ◽

Shanxi Province ◽

Freshwater Algae ◽

Preliminary Study ◽

Freshwater Red Algae ◽

Relationship Of

A catalogue and bibliography of Batrachospermales (Rhodophyta) in China is presented. There are 33 species belonged to 10 genera and 2 families. Species distribution among the 10 gen- era are as follows: Batrachospermum, 6; Kumanoa, 10; Montagnia, 1; Nothocladus, 1; Sheathia, 3; Sirodotia, 4; Torularia, 1; Virescentia, 1; Lemanea, 4; and Paralemanea, 2. According to geo- graphical distribution, the members of Batrachospermales in China are composed of 3 types: cos- mopolitan (distributed on at least 5 continents or 10 countries of the world), 6 taxa; regionally dis- tributed (distributed in no more than 4 continents or 10 countries), 15 taxa; and endemic to China (collected, described and reported only from China), 12 taxa. Most species were distributed in East and Southwest China, up to or more than 20 species. Eight species were recorded in North and Central China, respectively. Only 1 or 2 species were found in Northeast and South China, respec- tively. However, no one has been found in the northwest China so far. Thirteen species of Batra- chospermales in China have been confirmed by morphological characteristics combining with mo- lecular data. But unfortunately, the other species are unable to obtain molecular data because fresh collections are not available, which need to be confirmed or rejected in future studies. Kylin, H. (1912): Studien über die schwedischen Arten der Gattung Batrachospermum Roth und Sirodotia nov. gen. – Nova Acta Reg. Soc. Sci. Upsal., Series 4, 3 (3): 1–40. Li, L. C. (1939): Freshwater algae of Yunnan expedition 1935–1937. – Bull. Fan Mem. Inst. Biol., Bot. Series 9: 31–57. Li, L. C. (1940): Additions to the freshwater algae of Yunnan. – Bull. Fan Mem. Inst. Biol., Bot. Series 10: 47–67. Li, Q. & Xie, S. L. (2009): Studies on intraspecific variation of Batrachospermum gelatinosum (Rhodophyta). – J. Shanx. Univ. (Nat. Sci. Ed.) 32 (S1): 113–115. Li, Q., Ji, L. & Xie, S. L. (2010): Phylogenetic analysis of Batrachospemales (Florideophyceae, Rhodophyta) based on chloroplast rbc L sequences. – Acta Hydrobiol. Sin. 34 (1): 20–28. Liao, L. M. (2010): Nomenclatural notes on some Philippine species of freshwater red algae (Rhodophyta). – Phil. J. Syst. Biol. 4: 89–94. Linnaeus, C. (1753): Species Plantarum, Vol. 2. Impensis Laurentii Salvii, Holmiae. Luo, A. G., Hu, B. F. & Xie, S. L. (2009): A preliminary study on the alage in Jinci Park, Shanxi Province. – J. Jinzh. Univ. 26 (3): 51–54, 85. Lyons, T. W., Reinhard, C. T. & Planavsky, N. J. (2014): The rise of oxygen in Earth's early ocean and atmosphere. – Nature 506 (7488): 307–315. McNeey, J. A. (1994): Protected areas for the 21st century: working to provide benefits to society. – Biodivers. Conserv. 3 (5): 390–405. Montagne, C. (1850): Cryptogamia Guyanensis, seu plantarum cellularium in Guyana gallica annis 1835–1849 a Cl. Leprieur collectarum enumeratio universalis. – Ann. Sci. Nat., Bot., Trois. Série 14: 83–309. Nan, F. R., Feng, J. & Xie, S. L. (2014a): Phylogenetic relationship of genus Kumanoa (Batrachospermales, Rhodophyta) based on chloroplast UPA genes. – Bull. Bot. Res. 34 (5): 584–591. Nan, F. R., Feng, J. & Xie, S. L. (2014b): Advances on systematics of Kumanoa (Batrachospermales, Rhodophyta). – World Sci.-Tech. Res. Devel. 36 (3): 33–39. Nan, F. R., Feng, J. & Xie, S. L. (2015): Phylogenetic analysis of genus Kumanoa based on chloroplast psa A and psb A genes. – Acta Hydrobiol. Sin. 39 (1): 155–163.

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Pelagic species diversity, biogeography, and evolution

Paleobiology ◽

10.1017/s0094837300026956 ◽

2000 ◽

Vol 26 (S4) ◽

pp. 236-258 ◽

Cited By ~ 15

Author(s):

Richard D. Norris

Keyword(s):

Species Diversity ◽

Environmental Gradients ◽

Water Masses ◽

Morphological Data ◽

Airborne Spores ◽

Long Distance ◽

Population Exchange ◽

High Dispersal ◽

Population Sizes ◽

Parapatric Speciation

Pelagic (open-ocean) species have enormous population sizes and broad, even global, distributions. These characteristics should damp rates of speciation in allopatric and vicariant evolutionary models since dispersal should swamp diverging populations and prevent divergence. Yet the fossil record suggests that rates of evolutionary turnover in pelagic organisms are often quite rapid, comparable to rates observed in much more highly fragmented terrestrial and shallow-marine environments. Furthermore, genetic and ecological studies increasingly suggest that species diversity is considerably higher in the pelagic realm than inferred from many morphological taxonomies.Zoogeographic evidence suggests that ranges of many pelagic groups are much more limited by their ability to maintain viable populations than by any inability to disperse past tectonic and hydrographic barriers to population exchange. Freely dispersing pelagic taxa resemble airborne spores or wind-dispersed seeds that can drift almost anywhere but complete the entire life cycle only in favorable habitats. It seems likely that vicariant and allopatric models for speciation are far less important in pelagic evolution than sympatric or parapatric speciation in which dispersal is not limiting. Nevertheless, speciation can be quite rapid and involve cladogenesis even in cases where morphological data suggest gradual species transitions. Indeed, recent paleoecological and molecular studies increasingly suggest that classic examples of “phyletic gradualism” involve multiple, cryptic speciation events.Paleoceanographic and climatic change seem to influence rates of turnover by modifying surface water masses and environmental gradients between them to create new habitats rather than by preventing dispersal. Changes in the vertical structure and seasonality of water masses may be particularly important since these can lead to changes in the depth and timing of reproduction. Long-distance dispersal may actually promote evolution by regularly carrying variants of a species across major oceanic fronts and exposing them to very different selection pressures than occur in their home range. High dispersal in pelagic taxa also implies that extinction should be difficult to achieve except though global perturbations that prevent populations from reestablishing themselves following local extinction. High rates of extinction in some pelagic groups suggests either that global perturbations are common, or that the species are much more narrowly adapted than we would infer from current taxonomies.

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