Defoliation is an adaptation to environmental changes for some trees, and deciduous trees play important roles in ecosystem functional sustainability and community regeneration. Their proportion in tropical forests commonly changes along water gradients. To better understand the dynamics of deciduous trees during secondary succession, we conducted field investigations along a chronosequence of four recovery stages (stages I, II, III, and IV representing 5, 12, 25, and 55-year-old stands respectively) on abandoned shifting cultivation lands in Bawangling, Hainan Island. Twenty-four deciduous species with stems ≥0.1 m height were recorded from 5.25 hm ² stands (four recovery stages combined), which belong to 21 genera and 15 families. Bignoniaceae, Euphorbiaceae, and Mimosaceae contained the most deciduous species. Cratoxylum cochinchinens, Canthium horridum, and Glochidion fagifolium were the most abundant species, while Liquidambar formosana, C. cochinchinens, and G. fagifolium had the highest basal area. Contrary to the change in total species richness (evergreen and deciduous combined), deciduous species richness gradually decreased during secondary succession. Patterns of deciduous species richness change were similar across size classes. The deciduous species richness was higher for stems ≥5 cm DBH (diameter at breast height) than for stems <5 cm DBH. During secondary succession, the proportional changes of deciduous trees stem density and basal area showed unimodal patterns with peaks occurring in recovery stage II, and were similar for different-sized stems, with the except of saplings (height>1.5 m and DBH<5 cm). The secondary tropical lowland rain forests we studied share some characteristics with tropical monsoon forests during the same period of recovery on abandoned agricultural lands on Hainan Island.

Due to traditional forest management, many forest ecosystems in western Sichuan Province have become degraded. To quantify the composition and structure of bryophyte communities which are early in the natural recovery process, we sampled four sites with similar topographic situation, but at different points in the recovery process. All sites were located in the Rangtang County, Aba region, Sichuan Province. Species composition and structural parameters were surveyed between July and October of 2006. We used ANOVA analysis to detect differences among bryophyte communities, and nonparametric Spearman correlation to test for relationships between bryophyte structural parameters and environmental factors. We used regression analysis to explore the factors influencing bryophyte development. Our results suggested three main points. Firstly, dominant species composition changed during the natural recovery process. Some small-sized, heliophilous, and disturbance-resistant acrocarpous mosses with a high sporulation ability had expanded their populations, while some hygrophilous pleurocarpous mosses sensitive to early successional conditions had disappeared. Secondly, diversity indices, coverage, and biomass decreased during the natural recovery process, indicating that bryophyte communities became simplified with recovery progress. Thirdly, there was a close relationship between vascular plants and bryophytes. Bryophyte cover and richness were mainly influenced by herbaceous layer biomass, while bryophyte biomass was significantly affected by herbaceous layer height. Our results implied that different microhabitats resulting from vascular plant community development affected development of bryophyte communities.

The effects of long-term different fertilization regimes on weed species diversity were evaluated in this study. Seven different fertilization treatments, each with three replicated plots and 20 years of fertilization, were investigated in oilseed rape fields under a rice-oilseed rape cropping system in Tai Lake region. Overall, 17 weed species from 11 families were recorded. Of these, Alopecurus aequali,A. japonicas, Beckmannia syzigachne, Malachium aquaticum, and Geranium carolinianum had high population density, and were dominant in different plots. The weed species richness varied significantly among different fertilization treatments, ranging from 5 species in chemical fertilizer with oilseed rape stalk and rice straw treatment (CFOR) to 12 in N fertilizer treatment (NF). The composition and abundance of weed species also differed in different fertilization treatments. Shannon-Wiener index in NF was significantly higher than that in any other fertilization treatment while Simpson dominance index was the lowest. Pielou evenness index in non-fertilizer treatment (NoF) and NF were significantly higher than those in other fertilization treatments. As suggested by Whittaker index, chemical fertilizer and oilseed rape stalk treatment (CFO) and chemical fertilizer treatment (CF) had the most significant effects on weed community composition, chemical fertilizer and pig manure treatment (CFM) and chemical fertilizer and rice straw treatment (CFR) ranked the second, while NF and CFOR had no significant effect on weed community composition. Sørenson similarity index and clustering analysis suggested similar trends as Whittaker index. The results have indicated that the application of balanced N, P, K fertilizer and even plus organic manure (pig manure, oilseed rape stalk, and rice straw) was beneficial to effectively control dominant weeds and maintain weed species diversity by decreasing the abundance of those otherwise dominant species.

Soil seed banks are potential plant populations; therefore, their temporal and spatial patterns affect future plant community dynamics and stability. In the regions invaded by Eupatorium adenophorum, soil seed bank traits can play a key role in construction and function of future ecosystems. We studied the vegetation and soil seed banks in an area invaded by E. adenophorum in Panzhihua, Sichuan Province using a combination of field work and germination trails. We explored seed density and species composition in soil seed banks before and after a seed rain of E. adenophorum. The results showed that: (1) The experimental sites were so heavily damaged byE. adenophorum that the vegetation was simple; in shrub layers, mean coverage and frequency of Coriaria nepalensis, Ficus tikoua, Desmodiunm elegans, Abelia parvifolia and Pistacia weinmannifolia were higher than other shrubs. In herb layer, E. adenophorum, ranging in age between 0 and 4 years, was the most abundant as its Drude abundance was Soc and the frequency was 100%. (2) Seeds of 13 species were found in soil seed banks. The similarity index for species in the vegetation and in the soil seed bank was 0.31. The density ofE. adenophorum seeds was 1,950/m², accounting for 61.3% of total storage in the soil seed bank (3,180/m²), and there were not significantly (P>0.05) fewer seeds in upper layer than other layers. (3) Total seed storage before the seed rain ofE. adenophorum (1,950 seeds/m²) accounted for 41.2% of the storage after the seed rain (4,733 seeds/m²). After the seed rain, germination of E. adenophorum seeds from the soil showed two peaks at the 9th and 17th day, implying that seeds could periodically break dormancy. Our results indicated that E. adenophorum played a priority role in the soil seeds. The scarcity of other species in the seed banks was the main reason that E. adenophorum population regenerated and flourished continuously, and the invasion of E. adenophorum was hard to control.

The annual wild soybean (Glycine soja), known as the ancestor of the cultivated soybean (G. max), is endemic to East Asia with most of its range in China. It is believed that the wild soybean holds a reservoir of genetic variation potentially useful for improvement of cultivated soybeans. Our study combined molecular techniques with evaluation of botanical traits to investigate genetic diversity and genetic specificity caused by geographic differentiation in wild soybean populations in China. A total of 196 wild accessions from three distinct geographic regions (Northeast China, Huang-Huai-Hai Valleys and South China, abbreviated as NEC, HHH and SOC, respectively) were genotyped using 52 SSR markers and phenotyped using 10 botanical traits. The average allelic richness (NA) of the entire wild population and Simpson diversity index (H) were 16.1 and 0.852, respectively; higher than those of cultivated populations (NA = 11.4, H = 0.773). Among the three geographic populations, the SOC population had the highest genetic diversity (NA = 12.9, H = 0.842), the NEC population the next highest (NA = 12.4 and H = 0.834), and the HHH population the lowest (NA = 11.4, H = 0.805). Population-specific alleles existed on a number of loci (including AW132402 (Linkage group A2), Satt522 (F), satt150 (M), Sat_332 (D1a), Satt046 (K), sct_190 (K), thus indicating the existence of genetic differentiation among, and ecological specificity of geographic populations. Analysis of botanical traits revealed high variation, diversity (H= 0.710) and geographic differentiation, especially in growth period traits. These differences in botanical traits indicate the significance of natural selection due to geographic variation in day-length and temperature. Analysis of molecular data and botanical traits indicated that the geographic differentiation observed in botanical traits was based on genetic differentiation, and that genetic diversity of the SOC population was higher than the other two populations.

Temminck’s tragopan (Tragopan temminckii) and blood pheasant (Ithaginis cruentus) are two threatened species mainly distributed in China. However, we know little about the ecology of these two pheasants. Between May and August in 2006, we investigated foraging habitat selection by the two sympatric species in Liziping Nature Reserve in Sichuan Province, China, using line transect and systematic sampling methods. Temminck’s tragopans occurred at relatively low altitudes (1,950-3,450 m), while blood pheasants occurred at higher altitudes (2,760-3,800 m). No differences were found between the two species in terms of use of forest types. Both species preferred coniferous and mixed coniferous-broadleaved forest and they seldom occurred in forest areas with dense arrow bamboo (Fargesia spathacea). At the microhabitat scale, both species were consistently associated with dense tree coverage, and dense coverage of tall herbaceous plants. Home ranges of the two species contained more coniferous trees than random, and foraging sites were close to forest roads. We did detect some habitat use differences between the two species. Blood pheasant foraging habitats were associated with southwest-facing slopes, while Temminck’s tragopans did not select sites based on aspect. The habitats of Temminck’s tragopans were associated with lower arrow bamboo and sparse bamboo coverage compared to the control sites. There were more mixed coniferous-broadleaved forests and less forest-bamboo mixed forests in Temminck’s tragopans’ home ranges than in blood pheasants’ home ranges. We suggest that basic differences in habitat use can explain how the two species are able to maintain sympatric distributions.

Procambarus clarkiihas invaded many provinces in China, such as Jiangsu, Hubei, and Anhui. In order to evaluate its effect onRana limnocharis, we investigated the population density of P. clarkii and R.limnocharis in their natural habitat in Guilin between May and June in 2006. As a comparison, we also carried out indoor experiments to study P. clarkii predation on the tadpole of R. limnocharis and Microhyla ornata. The field investigation showed that there was a significantly negative correlation between the density of P. clarkii and that of R. limnocharis tadpoles, while indoor experiments showed that the number of R. limnocharis tadpoles preyed by Procambarus clarkii was positively correlated with P. clarkii’s body length, and moreR. limnocharis tadpoles were preyed than M. ornata tadpoles. Our results suggest that P. clarkii is likely to endanger amphibian larva, therefore, it should be monitored and controlled.

Genetic variations within and relationships between five indigenous Chinese yak (Bos grunniens) breeds (Pali, Sibu, Tibetan High Mountainous yak, Maiwa and Jiulong) were investigated using 16 microsatellite markers with the fluorescence-multiplex PCR technique. The gayal (Bos frontalis) was used as outgroup. For the six populations studied, number of effective alleles (N_e) ranged from 2.2043 to 3.2754, mean heterozygosity (H) ranged from 0.4858 to 0.6153, and mean polymorphism information content (PIC) ranged from 0.4230 to 0.5711. The five indigenous Chinese yak breeds had high genetic diversity at the microsatellite DNA level, while the gayal showed less genetic variation. The genetic differentiation among the populations was very low, with a Gst value of 0.0527. In neighbor-joining and fuzzy clustering trees, the five yak breeds grouped into two clades, one comprising Jiulong yaks and the other including Pali, Sibu, Tibetan High Mountainous yak and Maiwa yaks. Our results may provide a scientific basis for future conservation and exploitation of native Chinese yak breeds.

Soil management techniques such as mulching and intercropping have important effects on soil quality, and soil microbes are sensitive indicators of soil quality. We investigated the effects of fertilizer treatments on the functional diversity of soil microbial communities in tea plantations using the Biolog technique. Six treatments were designed, and the change rates of AWCD (average well color development, slope) ranked as follows: caky fertilizer + intercropping with white clover>NPK fertilizer + straw mulching>caky fertilizer+PK fertilizer+straw mulching>caky fertilizer+PK fertilizer+tillage>NPK fertilizer+intercropping with white clover>NPK fertilizer+tillage, indicating that intercropping and organic matter (caky) fertilizer improved the abundance and diversity of soil microbes to a certain extent. Biodiversity indices showed that neither straw mulching nor intercropping with white clover influenced microorganism species composition, but decreased the evenness of microbial communities. Our results also showed that both carbohydrate and carboxylic acid played important roles in the differentiation of carbon sources.

Research on airborne fungi can provide basic data for air pollution control and environmental protection. Between July 2005 and June 2006, we investigated the distribution and spatial and temporal changes of airborne fungi in Hefei City, Anhui Province. The samples were collected at four different sites, including a residential district, a main traffic line, a central business district, and a green park area. Thirty-five airborne fungi genera were identified. Dominant genera includedAspergillus, Penicillium, Mucor, Rhizopus, and Trichoderma. Our results indicated that the air in Hefei was polluted with airborne fungi. In the residential district, central business district and green park area, the airborne fungi concentration increased between morning and evening, while along the main traffic line it peaked at noon. Airborne fungi concentration did not vary seasonally in the residential district or main traffic line; however, in the central business centre and green park area, fungi concentration was higher in spring and autumn than in summer and winter. Airborne fungi concentration was affected not only by air pollution, but also by human activity and vegetation distribution.

Based on literature, preserved specimens and field investigation, we compared species diversity and composition of bryophytes in the Xujiahui area of Shanghai between the early of 20th and 21th centuries. A total of 24 bryophyte species were recorded in this area between 1906 and 1910. Of these, 15 were described as new species, however only 6 species and 1 variety are currently still accepted as valid species. On the other hand, 21 bryophyte species were found in the area during this investigation. During the past 100 years, there were no distinct effects of environmental change on bryophyte diversity; however, bryophyte species composition changed almost completely. Besides one, Plagiomnium acutum, we found none of the type species reported in the early of 20th century from Xujiahui. The number of small and ground bryophyte species, including Bryaceae and Funariaceae species, increased, whereas epiphytic bryophyte decreased. Some cosmopolitan species with good resistance to human disturbance became more common. We propose suggestions for bryological conservation in urban areas.

Cave fauna is an important component of biodiversity. Guangxi has the most spectacular Karst scenery in China beneath which lies a plenty of unexplored cave fauna. However, very little research has been carried out to document them. We collected and identified 180 cave animal specimens, from eight caves in Yachang Nature Reserve, Leye County, NW Guangxi between May and June of 2007. These specimens belonged to 4 phyla, 10 classes, 20 orders, 31 families, and 36 species/groups. Among them, cave crickets, millipedes and spiders are the most widely occurring animals, while Cololembola, Scolopendromorpha, the mosquitoes and flies of Diptera are widely distributed. Blattaria and Neuroptera are only occasionally found. There are more cave animals in wet or longer caves than in dry or shorter ones. In the same cave, dry segment has less cave animals than wet segment. In general, moderate temperature, high humidity, a stable cave environment and an absence of exotic invasive species provides an ideal habitat for cave animals. Unfortunately, we found that some caves have been seriously damaged due to the lack of conservation, which threatens the survival of cave fauna. To avoid loss of Chinese cave biodiversity, we should arouse public awareness of protecting the cave environment. Furthermore, laws of cave biodiversity protection should be made as soon as possible.

Fish assemblages were investigated at four sites in the upper reaches of Huangpu River and Suzhou Creek, Shanghai, China monthly between June 2005 and May 2006. Forty four fish species in total, belonging to 10 orders, 14 families, 35 genera, were recorded. A total of 30 species belonging to 6 orders, 10 families and 25 genera, were recorded at Baihe and Huangdu on Suzhou Creek, and a total of 39 species belonging to 10 orders, 13 families and 32 genera were collected at Dianfeng and Songpu Bridge on the Huangpu River. Spatio-temporal distribution patterns were observed for the diversity of fish assemblages, with greater species richness in summer and autumn than in winter and spring, and higher species diversity in the upper Huangpu River than in Suzhou Creek. The fish community at Baihe was highly similar to those at the two sites in the Huangpu River, whereas the fish community at Huangdu station was moderately dissimilar to those at the two Huangpu River sites. Between-stream variation in community composition was greater than within-stream variation. Fish communities at the four sites were dominated by omnivore species, which occupied 51.5-62.5% of the communities, and sedentary species. Songpu Bridge had the highest species richness of river-sea migratory species and river-lake migratory species. The results suggested that the fish assemblages at the four sites are somewhat spatially isolated. Further, water quality and interconnectedness of waterways may be important factors influencing diversity of fish species in upper Suzhou creek. It was suggested that higher species diversity of fish in the upstream section of Huangpu River was due to a larger volume of water body, better interconnectedness of waterways and water quality.

Based on fossils evidence, argali (Ovis ammon) were formerly distributed in northeastern, northwestern, southwestern, and northern China, including areas south of the Yellow River. The species no longer exists in majority of these locations. Argali inhabited in grasslands, foothills, and mountain ranges during the Pleistocene era. Based on the distribution of rock carvings and cliff paintings, argali lived in mountainous regions and plateaus during the Stone Age; however, the species disappeared from northern China. In this paper, we primarily used field observation to investigate the distribution of argali in China, excluding Xinjiang. In the Qilian Mountains, argali were concentrate in the Danghenan and Yema’nan Ranges of the western Qilian Mountains. No recent surveys have been conducted in the Tolainan and Shulenan Ranges, which until the 1980s still contained a few animals. The only recent reliable sighting of argali in this region was made in the hills near Dunhuang, between the Qilian Mountains and the Mazong Mountains. In the Altun Mountains, argali were observed in all the surrounding mountainous areas of in two major regions: from Sorkali to the southern Altun Mountains and from the northern Altun Mountains to the western Qilian Mountains. In Kunlun Mountains, scattered argali were found throughout most of the major plateau regions, except in the east. If any sheep survive in area along the northern slopes of the western Kunlun Mountains, they are probably on the verge of extirpation. Argali occurred as dispersed populations in the Kekexili, Qiangtang, and North Xizang Ranges. The highest densities of argali survived in the eastern Kunlun Mountains near Burhanbuda and Bayankala. The northern slope of Himalayas supported one of the largest populations of argali in Xizang. Recent surveys found argali populations in several areas along the southern part of the Yaluzangpo River, including Langkazi, Gangba, and Yadong. Reliable sightings suggest they also live in Cuona, further east along the border with Bhutan. In Inner Mongolia, argali previously occurred throughout the mountains and foothills of the Inner Mongolia Plateau that stretches from Daqingshan in the east to Alashan and Mazongshan to the extreme west. At the time of our surveys, the sheep still exists in some populations in Sunitezuoqi and Siwangziqi and further north toward the border with Mongolia. In Mazongshan, surveys confirmed small populations restricted to the mountain ranges on the border with South Gobi Province, Mongolia.