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With the continuous development of gold ore prospecting and exploration in recent years a new type of micro-disseminated gold deposits have been found in the regions of Southwest Guizhou Province and Northwest Guangxi Zhuang Autonomous Region, with the orebodies directly occurring in diabase or in the contact zone between diabase and strata. The orebodies are strictly controlled by fault structures. The discovery of this type of gold deposits has brought about new prospects for gold ore prospecting in the Yunnan-Guizhou-Guangxi Golden Triangle region. From the preliminary analysis of the geological characteristics of the Qiaoxiang gold deposit in Wangmo County, in combination with the results of research work in the adjacent areas in recent years, this paper roughly described the geological characteristics and metallogenic conditions of this type of gold ore deposits with an attempt to make more and more geologists pay enough attention to this type of gold ore deposits, so as to promote gold ore prospecting in Guizhou Province to develop toward a variety of types of gold deposits in all round way. [ABSTRACT FROM AUTHOR]

There has been a conflicting issue in rural China that whether or not encouraging the development of medium–large-scale biogas plants (MLBPs) to reduce household biogas digesters (HBDs) will be better for China in the long run. In this study, we investigate the difference between HBD users and MLBP users and the factors that affect the biogas use of these two user types on the basis of a survey of 1125 households in four provinces in China. The results indicate that compared to HBD users, MLBP users have a higher ratio (29%) of biogas use, obtain a higher subsidy-to-cost ratio (25%), and present a more positive evaluation of biogas service (3%). For HBD users, installation years and service evaluation are significant predictors of biogas use. For MLBP users, in addition to installation years and service, the subsidy-to-cost ratio affects biogas use negatively, and the biogas price is a key constraint for biogas use. These results provide valuable insights into the future development of biogas energy in rural China and guidance for the development of biogas in similar countries worldwide. [ABSTRACT FROM AUTHOR]

Guizhou Karst Plateau is located at the center of the karst region in Asia, where landslides are a typical disaster. Affected by the local karst environment, the landslides in this region have their own characteristics. In this study, 3975 landslide records from inventories of the Guizhou karst plateau are studied. The geographical detector method is used to detect the dominant casual factor and predominant multi-factor combinations for the local landslides. The results show that landslides are prone to areas on slopes between 10° and 35°, of clay rock, in close proximity to gullies, and especially in areas of moderate vegetation, dryland, and mild rocky desertification. Continuous precipitation over 10 days has a great effect on landslide occurrence. Compared with the individual factors, the impact of two-factor interaction has greater explanatory power for landslide volume. The volume of earthquake-induced landslides is predominantly controlled by the interactions of faults and slopes, while that of human-induced landslides is affected by the interactions of land cover and hydrological conditions. For rainfall-induced landslides, the dominant interactions vary in different regions. In the central karst basin, the interactions between faults and precipitation can explain over 90% of the variations in landslide volumes. In the southern hilly karst region, the interactions between lithology and slope can explain over 71% of the variations in landslide volume and those between fault and land-use can explain 50% of the variations of the landslide volumes in the northeastern mountainous karst region. [ABSTRACT FROM AUTHOR]

As an effective livelihood approach to alleviate poverty without rural population migration, ethnic tourism has become the primary choice of economic development in ethnic areas worldwide in addition to traditional livelihood approaches. This article applies the theories of livelihood to study the community evolution driven by tourism livelihood and examine three mountainous tourism communities in different stages of tourist area life cycle. Drawing on the methods of GIS spatial analysis, semi-structured interviews and questionnaires, this article proposes a sustainable livelihood framework for ethnic tourism to explore the evolution of ethnic tourism communities by identifying changes in livelihood assets (natural, financial, social, cultural and human capitals) in the process of tourism development. The results show that the development of ethnic tourism has led to changes in the increase of building land, and the diversification of land use functions with a trend of shifting from meeting local villagers' living needs to satisfying tourists, income composition and uneven distribution of tourism income spatially. Ethnic tourism also led to the deterioration of traditional social management structure, collapse of neighboring relationship, the over- commercialization and staged authenticity of ethnic culture, as well as the gradual vanish of agricultural knowledge with a trend of increasing modern business knowledge and higher education. In addition, these changes, involving livelihood assets from natural, economic, human, social and cultural aspects are interrelated and interactive, which form new evolution characters of ethnic community. This study reveals the conflicts over livelihood approaches which have formed new vulnerabilities to impact on sustainable evolution of ethnic communities. This research provides implications for achieving the sustainable development of ethnic communities with the driving force of tourism livelihood. [ABSTRACT FROM AUTHOR]

Here is currently little consensus on the branching order and phyletic status of the oldest metazoan groups, but sponges are widely believed to be the earliest-branching living metazoans. Porifera are thought to have diverged before the emergence of developmental characters typical of Eumetazoa, such as well-defined symmetry; extant sponges show radial symmetry of indeterminate high order, or none, combined with polarisation along the axis. In contrast, other early-branching phyla include bilateral and tetraradial (Cnidaria) and biradial (Ctenophora) symmetry, or none (Placozoa). A variety of prismatic early fossil sponges had shown here where the shared symmetry has been overlooked, and also describe structural tetraradial symmetry in Cambrian sponges from South China. Based on this study, this symmetry is likely to have been a primitive feature of sponges, and that the earliest-known fossil sponges were highly organised, cellularly integrated individuals whose body form was under strict genetic control. [ABSTRACT FROM AUTHOR]

The purpose of this study is to present a weighting method, integrating subjective weight with objective weight, for landslides susceptibility mapping based on geographical information system (GIS). First, the landslide inventory, aspect, slope, proximity to streams of drainage network, proximity to railway, proximity to road, topography, elevation, lithology, tectonic activity and annual precipitation, including their subclasses, were taken as independent landslide causal factors. Second, objective weights of the causal factors were calculated according to the landslide area density based on entropy weighting method, and key factors were selected according to the rank of the objective weights. Third, trapezoidal fuzzy number weighting approach was used to assess the sub-classes of each key factor. Finally, a case study was carried out in Guizhou province, China. A landslide susceptibility map was created using weighted linear combination model based on GIS. Using a predicted map of probability, the study area was classified into four categories of landslide susceptibility: low, moderate, moderate-high, and high. [ABSTRACT FROM AUTHOR]

The karst area accounts for 61.9% of the total area in Guizhou Province, which gives rise to a fragile environment and backward economy. Comparative studies on the element contents of rock and soil and agriculture production in both carbonate area and non-carbonate area have been made to establish factors leading to low output and poor quality of agricultural products in the karst area. The result shows that there is an apparent lack of nutrient elements in carbonate rocks. The trace element contents of carbonate rocks are only 3532.27×10, but those of non-carbonate rocks are 10894.21×10. The available element contents in cultivated soil delivered from carbonate rocks are merely 101.4×10, but those from non-carbonate rocks are 326.05×10. The available element contents and total element contents in cultivated soil delivered from non-carbonate rocks are 3 times higher than those from carbonate rocks. Besides, high-quality agricultural products such as rice, potato and tea are mainly produced in the non-carbonate area. It is indicated that the low output and quality of agricultural products are caused by the above-mentioned low trace element contents and poor agricultural environment. Therefore, a new method of mineral nutrients compensation has been put forward, which is very effective to raise the load-bearing capacity of agricultural environment, agricultural output and quality of agricultural products. [ABSTRACT FROM AUTHOR]

Low molecular weight (LMW) organic acids are important and ubiquitous chemical constituents in the atmosphere. A comprehensive study of the chemical composition of precipitation was carried out from June 2007 to June 2008 at a rural site in Anshun, in the west of Guizhou Province, China. During this period, 118 rainwater samples were collected and the main LMW carboxylic acids were determined using ion chromatography. The average pH of rainwater was 4.89 which is a typical acidic value. The most abundant carboxylic acids were formic acid (volume weight mean concentration: 8.77 µmol L-1) and acetic acid (6.90 µmol L-1), followed by oxalic acid (2.05 µmol L-1 ). The seasonal variation of concentrations and wet deposition fluxes of organic acids indicated that direct vegetation emissions were the main sources of the organic acids. Highest concentrations were observed in winter and were ascribed to the low winter rainfall and the contribution of other air pollution sources northeast of the study area. The ratio of formic and acetic acids in the precipitation ([F/A]T) was proposed as an indicator of pollution source. This suggested that the pollution resulted from direct emissions from natural or anthropogenic sources. Comparison with acid precipitation in other urban and rural areas in Guizhou showed that there was a decreasing contribution of LMW organic acids to free acidity and all anions in rainwater from urban to remote rural areas. Consequently, it is necessary to control emissions of organic acids to reduce the frequency of acid rain, especially in rural and remote areas. [ABSTRACT FROM AUTHOR]

According to systemically monitoring results of oxygen (hydrogen) isotope compositions of precipitation, soil waters, soil CO2, cave drip waters and their corresponding speleothems in Liangfeng Cave (LFC) in Guizhou Province, Southwest China, it is found that local precipitation is the main source of soil waters and drip waters, and that the amplitudes of those δ18O values of three waters (precipitation, soil water and drip water) decrease in turn in the observed year, which are 0‰ to -10‰, -2‰ to -9‰ and -6‰ to -8‰, respectively. Moreover, the δ18O values for three waters show a roughly simultaneous variation, namely, that those values are lighter in the rainy seasons, weightier in the dry seasons, and that the average δ18O value of drip waters is about 0.3‰ weightier than that of precipitation, which is modified by surface evaporation processes. We also find that oxygen isotope equilibrium is reached or neared in the formation processes of speleothems in LFC system, and that it is feasible to reconstruct paleotemperature and paleoprecipitation by using δ18O values of speleothems. However, it should be noted that surface evaporation would affect the oxygen isotope values in the study area. [ABSTRACT FROM AUTHOR]

Studies of two Permian-Triassic boundary (PTB) sections on top of a Changhsingian reef in Ziyun, Guizhou Province, southwestern China indicate that the end-Permian mass extinction of reef ecosystems occurred in two steps. The first step is the extinction of all stenotropic organisms such as calcisponges and fusulinids in the latest Permian (in the Clarkina yini conodont zone). The biota after the first extinction is simple, comprising eurytropic organisms including microgastropods, ostracods, and some small burrowing organisms, or only algal mats. At the beginning of the Early Triassic (i.e. the beginning of the Hindeodus parvus zone), the environments became anoxic, and the microgastropod dominated biota or algal mats disappeared, which constituted the second episode of the mass extinction. The biota after the second extinction comprises small spherical microproblematica, some kinds of specialized organisms tolerant of anoxic or oxygen-poor conditions. As the environments became oxygenated, the specialized biota was replaced by a microgastropod-dominated simple biota. When the environmental conditions improved further, the simple biota was replaced by a diverse biota with normal-sized ammonoids, bivalves, and gastropods, representing restoration of normal oceanic conditions. Comparison with PTB sections in Dolomites, Italy and Meishan, Zhejiang Province shows that non-reef ecosystems had a similar first episode of mass extinction in the latest Permian. In the case that oceanic anoxia happened, non-reef ecosystems had a second extinction episode similar to that of reef ecosystems. [ABSTRACT FROM AUTHOR]

The article presents abstracts of several studies on environmental geochemistry. Some of the abstracts presented include "Biogeochemical Cycling of Nutrients in Karstic Catchments, Southwestern China: Linkages to Changes of Eco-Environments," by Congqiang Liu and "Emerging Organic Contamination in China," by Guibin Jiang and colleagues.

Focuses on a study on the geochemical behavior of cadmium (Cd) and its environmental effects under supergene weathering-leaching conditions in the Niujiaotang Cd-bearing zinc deposit in Guizhou Province, China. Geological setting of the deposit; Experimental and analytical methods; Experimental results and discussion; Conclusions.

Focuses on a study of the state of cadmium (Cd) in the Niujiaotang Cd-rich zinc deposit in Guizhou, China. Geological setting; Distribution characteristics of Cd in ores and minerals; Conclusions and discussion.