Northwest Guangxi Research Articles

桂西北农村小学教师主观幸福感调查

桂西北农村小学教师主观幸福感调查

Ecological risk assessment of landslide disasters based on potential loss of ecosystem services

Landslides are common geological calamities in mountainous regions, which not only threaten social and economic development and residents' safety but also cause ecosystem damage, with consequences on human welfare. A more comprehensive and systematic reference for disaster prevention and mitigation with ecosystem services loss as an index for the potential damage of ecosystem could aid the progress of landslide ecological risk assessment. Five provinces in Southwest China (Sichuan, Yunnan, Guizhou, Guangxi and Chongqing) have diverse landforms, complex stratum and lithology, and active geological tectonic movements, which are the most landslide prone areas in China. In this study, the ecological risk assessment framework, model and indicator were constructed from three dimensions, including disaster risk, vulnerability and potential loss of the ecosystem. Disaster risk was based on the comprehensive analysis of factors such as geology, topo-graphy, landform, precipitation, and their mutual relationship. The vulnerability of the ecosystem was characterized by landscape patterns indices. The potential loss was measured by ecosystem service to evaluate the ecological risk associated with landslide hazards in the five provinces of Southwest China. The results showed that the areas with high potential loss of ecosystem services were mainly distributed in the south of Ailao Mountain in Yunnan Province, Qionglai Mountain of Sichuan Pro-vince, Hengduan Mountains, Dadu River Basin, Northwest Guangxi Autonomous Region, and eastern area of Dayao Mountain. The high ecological risk of landslide hazard in the study area mainly distributed in the areas of Min Mountain, Qionglai Mountain, Wuliang Mountain, Ailao Mountain, Miao Ridge, Leigong Mountain, and Dadu River basin. With respect to altitude, 500-1500 m was the main high-risk areas, accounting for 37.9% of the high-risk area. In terms of ecosystem types, forests are the high-risk areas, accounting for 66.4% of the high-risk areas. Landslide monitoring and early warning in the high ecological risk areas should be strengthened, through strengthening ecosystem protection in the region and improving the stability and resistance of ecosystems.

The most remarkable cave-specialized trechine beetles from China

Limestone areas of China host remarkable radiations of cave animals. The subterranean trechine beetles (Carabidae: Trechini), the most diverse and modified group of subterranean beetles in the world, are extremely diverse in southern China. The first aphaenopsian trechine beetle, Sinaphaenops mirabilissimus Uéno & Wang, 1991 was reported from a limestone cave in Guizhou province. Up to now, 146 species within 48 genera of aphaenopsian trechine have been described in China after almost three decades. Among them, the genera Giraffaphaenops, Xuedytes, Dongodytes, Sinaphaenops and Pilosaphaenops from northwest Guangxi and south Guizhou are the most modified troglobitic trechine beetles known so far in the world. They are remarkable by their morphology combining extremely slender body and elongated appendages. Some of them are diversified or quite widespread, which is not the case of Xuedytes Tian & Huang, 2017, a remarkable monospecific genus known from a single locality so far. In addition to the surveys and collection of specimens, an integrative approach combining the study of systematics, phylogeny, diversification and biogeography patterns of the cave trechine beetles in China is on the way, in order to understand the origin of the remarkable biodiversity and evolutionary success of this group.

Qualitative identification of hydrologically different water sources used by plants in rock-dominated environments

Sources of water used by plants in rock-dominated environments are far less clear than those in relatively homogeneous soils, largely because plants in rocky environments normally expose to more complex substrate conditions and their potential water sources are hard to locate and sample. In the current study, potential water sources for plants growing on cliff-face (a typical kind of rock-dominated environment) were roughly separated into two water pools based on their hydrological differences. A variable pool that is composed of water derived from recent precipitation that has rapid fluctuations in water content due to recharge by precipitation and depletion by transpiration, and a constant pool that is characterized by slower changes in water status because it can only be recharged by precipitation under certain conditions and depleted by transpiration of deep-rooted species. This study was conducted in a typical karst catchment of Northwest Guangxi, Southwest China. Stem water samples for the most common dominant tree species of cliff-faces and rainwater for each rain event were consecutively collected throughout the growing season. A co-occurring shrub species, which was identified to have a shallow root system, was further selected as a reference species. The reliance on different water pools was qualitatively identified based on the deviation of stem water isotope values between current and last sampling times, as well as its relationship to the isotope values of rainfall between these two sampling times. Our results showed that the shrub species continuously relied on water from the variable water pool, which was consistent with its shallow root system. While the dominant tree species shifted from the constant pool during the early wet season to the variable pool during the mid-wet season, then back to the constant pool during the early dry season. Moreover, the divergent reliance on different water pools by the two species was further supported by the species-specific dynamics in the efficiency in water use by various plants (reflected by leaf carbon isotope ratio). Our results provide new insights into the linkages between plant transpiration and hydrologically different water pools, which would be helpful in understanding the hydrological importance of different plant species.

Contributions of the medical alliance of northwest Guangxi hospitals in the health anti-poverty campaign

To implement the task of health anti-poverty campaign, the medical alliance of northwest Guangxi hospitals made full use of its synergy strengths to achieve remarkable progress in constructing a telemedicine cooperation network, nurturing medical discipline of primary hospitals in the alliance, promoting regional medical resources sharing, and improving the humanities connection mechanism. To further develop health anti-poverty via medical alliances, relevant institutions are recommended to probe into such problems as telemedicine compensation mechanism, precision-based disciplinary support, breakdown of resource sharing barriers and profit distribution mechanisms. Key words: Health resources; Medical alliance; Telemedicine; Health anti-poverty campaign; Hierarchical medical system

Effect of ecological engineering projects on ecosystem services in a karst region: A case study of northwest Guangxi, China

Abstract Ecological efficiencies of rocky desertification control measures at the regional scale remain unclear. It is urgent and challenging to determine the influences of ecological engineering on the variations of ecosystem services, and to evaluate the ecological benefit of rocky desertification control measures. In this study, variations of three kinds of ecosystem services (water regulation, soil conservation, and carbon sequestration) were analysed in a typical karst region of Northwest Guangxi China during the period from 2000 to 2010. The relative importance of the main factors that influence these three ecosystem services were analysed using radial basis function network, Kaiser–Meyer–Olkin (KMO), and principal component analysis. The results showed that over half of the study area has experienced an increase in water regulation (50.39%) and soil conservation (58.53%), and approximately 28.24% of the study region has undergone increased carbon sequestration. Environmental factors had a substantial impact on the ecosystem services, and the order of relative importance was as follows: geology > soil > vegetation > temperature > precipitation. Anthropogenic activities have played an important role in the changes to the ecosystem services. In addition to the significant conversion of other land types to woodland (approximately 46.80% of the total transfer area), the vegetation species, shape, and fraction, which are greatly influenced by human activities, contributed 79.05% to the variance. This resulted in a high KMO value of 0.912 (>0.9, represents very suitable), and the Bartlett test was significant (Sig. 0.00). These results showed that although natural environmental factors remained basic influences on the pattern of ecosystem services, anthropogenic activities of ecological engineering projects also had important and positive influences on the ecosystem services. This study also indicated that satellite images and new methods should be applied to deal with the relative lack of existing datasets.

Heavy metal contents and enrichment characteristics of dominant plants in wasteland of the downstream of a lead-zinc mining area in Guangxi, Southwest China

A field investigation on the content of heavy metals in soils and 17 kinds of dominant plants from wasteland of the downstream of a Pb-Zn mine in Northwest Guangxi Zhuang Autonomous Region was carried out. The absorption and accumulation characteristics of heavy metals between plants and soil were compared, and the candidate species for ecosystem restoration of the area were selected. The results indicated that the soils had been subjected to pollution of heavy metals in varying degrees. The concentrations of Cd, Pb, Zn were 46.5, 57.3 and 23.7 times higher than their corresponding background values, respectively. The contents of Cd, Pb and Zn in the most analyzed plants exceed the normal ranges and the phytotoxic level. C. crepidioides, S. nigrum, B. pilosa, C. Canadensis, A. conyzoides, I. denticulata and E. crusgali showed strong capability in accumulation and transport of Cd, and they could be used as good candidates for Cd- phytoextraction. Among which, Cd concentration in the aerial part of C. crepidioides exceeded the threshold of Cd-hyperaccumulator. Thus, C. crepidioides demonstrated the basic characteristics of a Cd-hyperaccumulator. The lower translocation ratios for Cd, Cu, Zn and Pb in P. vittata and C. chinensis make them suitable for phytostabilization in the study area.

FACTORS AFFECTING THE PATTERN OF VEGETATION CARBON DENSITY IN A KARST REGION IN NORTHWEST GUANGXI, CHINA

The changing characteristics of vegetation carbon patterns in the karst region of northwest Guangxi, China and their impact factors were analyzed on the basis of vegetation inventory data from 2005 to 2010. A radial basis function network model (RBFN) was constructed using data from 1377 samples and 13 environmental factors. The results for the 5-year study period were as follows: (1) The total carbon storage of vegetation had increased with an annual growth rate of 1.84% and the carbon density of vegetation increased from 29.04 t hm-2 to 29.57 t hm-2. The carbon density in the west (>40 t hm-2) was greater than that in the Middle East (<25 t hm-2). Hot spot analysis revealed a random distribution of vegetation carbon density in 2005, but a highly aggregated distribution in 2010. (2) The four most important impact factors on spatial distribution of vegetation carbon density in this area were land type, forest type, forest category, and vegetation type (significance <50%). The least important factors were location, slope, aspect, and elevation (significance of 2 11%). Vegetation carbon density increased significantly with the implementation of rocky desertification control measures. Factors changed by human activities had much greater impacts than topographic factors on the spatial distribution of vegetation carbon density. Therefore, the Ecological Immigration Program, returning farmland to forests, and rocky desertification control measures had an important effect on the pattern of vegetation carbon density. Key words: Guangxi China, impact factors, karst, northwest, pattern characteristic, radial basis function network (RBFN), vegetation carbon

Relative importance of climate changes at different time scales on net primary productivity-a case study of the Karst area of northwest Guangxi, China.

Climate changes are considered to significantly impact net primary productivity (NPP). However, there are few studies on how climate changes at multiple time scales impact NPP. With MODIS NPP product and station-based observations of sunshine duration, annual average temperature and annual precipitation, impacts of climate changes at different time scales on annual NPP, have been studied with EEMD (ensemble empirical mode decomposition) method in the Karst area of northwest Guangxi, China, during 2000-2013. Moreover, with partial least squares regression (PLSR) model, the relative importance of climatic variables for annual NPP has been explored. The results show that (1) only at quasi 3-year time scale do sunshine duration and temperature have significantly positive relations with NPP. (2) Annual precipitation has no significant relation to NPP by direct comparison, but significantly positive relation at 5-year time scale, which is because 5-year time scale is not the dominant scale of precipitation; (3) the changes of NPP may be dominated by inter-annual variabilities. (4) Multiple time scales analysis will greatly improve the performance of PLSR model for estimating NPP. The variable importance in projection (VIP) scores of sunshine duration and temperature at quasi 3-year time scale, and precipitation at quasi 5-year time scale are greater than 0.8, indicating important for NPP during 2000-2013. However, sunshine duration and temperature at quasi 3-year time scale are much more important. Our results underscore the importance of multiple time scales analysis for revealing the relations of NPP to changing climate.

Hydrological characteristics of calcareous soil with contrasting architecture on dolomite slope of Northwest Guangxi

The traditional hydrology method, stable hydrogen and oxygen isotope technology, and rainfall simulation method were combined to investigate the hydrological function of small experimental plots (2 m×1.2 m) of contrasting architecture in Northwest Guangxi dolomite area. There were four typical catenary soils along the dolomite peak-cluster slope, which were the whole-sand, up-loam and down-sand, the whole loam, up-clay and down-sand soil types, respectively. All the experimental plots generated little amounts of overland runoff and had a high surface infiltration rate, ranging from 41 to 48 mm·h-1, and the interflow and deep percolation were the dominant hydrological progress. The interflow was classified into interflow in soil clay A and C according to soil genetic layers. For interflow in soil clay A, matrix flow was generated from the whole-sand, up-loam and down-sand, up-clay and down-sand soil types, but preferential flow dominated in the whole-loam soil type. As for interflow in soil clay C, preferential flow dominated in the whole-loam, up-clay and down-sand, up-loam and down-sand soil types. The soils were shallow yet continuously distributed along the dolomite slope. The difference of hydrological characteristics in soil types with different architectures mainly existed in the runoff generation progress of each interface underground. It proved that the a 3-D perspective was needed to study the soil hydrological functions on dolomite slope of Northwest Guangxi, and a new way paying more attention on underground hydrological progress should be explored to fully reveal the near-surface hydrological processes on karst slope.

喀斯特石漠化地区不同退耕年限下桂牧1号杂交象草植物-土壤-微生物生态化学计量特征

PDF HTML阅读 XML下载 导出引用 引用提醒 喀斯特石漠化地区不同退耕年限下桂牧1号杂交象草植物-土壤-微生物生态化学计量特征 DOI: 10.5846/stxb201508181723 作者: 作者单位: 中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室 作者简介: 通讯作者: 中图分类号: S153.6 基金项目: 中国科学院科技服务网络计划（STS计划）资助项目（KFJ-EW-STS-092）；国家自然科学基金资助项目（41471445） Ecological stoichiometric characteristics of plants, soil, and microbes of Pennisetum purpureum cv. Guimu-1 pastures at different rehabilitation ages in a karst rocky desertification region Author: Affiliation: Institute of Subtropical Agriculture, Chinese Academy of Sciences,,Institute of Subtropical Agriculture, Chinese Academy of Sciences,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:耕地农作物种植与退耕地种草养畜是喀斯特主要的农业生产模式。以喀斯特地区农耕玉米地为对照，研究退耕还草1、5、7a（恢复初期、旺盛期、衰退期）3种年限下桂牧1号杂交象草地植物-土壤-微生物C、N、P生态化学计量特征及内在关联。结果表明：1）牧草地植物地上部分N、P含量均为5a牧草 < 1a牧草 < 7a牧草，C含量则刚好相反；3种退耕年限牧草地植物地上部分C：N、C：P、N：P分别为26.50-33.91、631.70-2254.33、23.89-67.21，且均表现为7a牧草 < 1a牧草 < 5a牧草。2）土壤表层（0-10 cm）C、N、P含量均以玉米地最低，3种退耕年限牧草地中则均为5a牧草地最低；土壤C：N、C：P、N：P在玉米及退耕牧草地之间均无显著差异（P > 0.05），平均值分别为9.20，27.88，3.38。3）玉米及牧草地土壤MBC、MBN、MBP含量存在显著差异（P < 0.05）；玉米地MBC/SOC、MBN/TN、MBP/TP均高于牧草地，3种退耕年限牧草地中，则均为5a牧草地最高。4）MBC、MBP与土壤C、P含量分别呈显著线性正相关（P < 0.05）；植物C、C：N与土壤C、N含量均呈极显著线性负相关（P < 0.01）。分析表明，退耕还草地中植物与土壤系统C-N-P化学计量比表现出不一致的时间变化特征，且牧草地植物受P限制严重，尤以恢复旺盛期为甚。 Abstract:Ecological stoichiometry has become the focus of research in ecological sciences in recent years and many studies have examined the carbon:nitrogen:phosphorus (C:N:P) stoichiometry of plants, soil, or litter in forest communities. However, few studies have explored the stoichiometric characteristics of herbs at different ages. Elephant grass, Pennisetum purpureum cv. Guimu-1, is a tall perennial C4 grass that can withstand repeated cutting and regenerates rapidly, and has been widely cultivated in northwest Guangxi, China because of the "grain for green" policy. For enhanced understanding of the nutrient cycling characteristics of artificial forage at different time scales in fragile karst ecosystems, we investigated the C:N:P stoichiometric characteristics of plant-soil-microbe interactions in Guimu-1 pastures of different growth ages. Corn and three different restoration stage pastures (1-, 5-, and 7-y-old Guimu-1 pastures, representing initial restoration, vigorous restoration, and degenerating stages, respectively, after returning farmland to grassland) were chosen in northwest Guangxi, China to determine the C, N, and P contents and the C:N:P stoichiometry. The results showed that:(1) the C, N, P contents and C:N:P ratios in the aerial portion of plants varied with different artificial Guimu-1 pasture ages. The N and P contents of the plant aerial portion in different years all followed the same order:5-y-old < 1-y-old < 7-y-old pastures, whereas the C content followed the reverse order. Plant C:N, C:P, and N:P ratios, which varied over a large range from 26.50 to 33.91, 631.70 to 2254.33, and 23.89 to 67.21, respectively, were all in the order of 7-y-old < 1-y-old < 5-y-old pastures. (2) Soil C, N, and P in the topsoil layer (0-10 cm) all showed the same order:corn field < 5-y-old < 1-y-old < 7-y-old pastures. However, there were no significant differences among the soil C:N, C:P, and N:P ratios for the four herb types (P > 0.05), with average values of 9.20, 27.88, 3.38, respectively. (3) Soil microbial C biomass (MBC), microbial N biomass (MBN), and microbial P biomass (MBP) showed significant differences among the different plant types (P < 0.05). The corn field had the highest MBC/soil organic C, MBN/total N, and MBP/total P ratios among the four plant types, while the 5-y-old pasture had the highest ratios among the three different aged pastures. (4) Correlation analysis showed that:(a) there were significant positive linear correlations between MBC and soil C, and MBP and soil P (P < 0.05); (b) there were highly significant negative linear correlations between plant and soil C, plant C and soil N, plant C:N and soil C, and plant C:N and soil N (P < 0.01); and (c) there were highly significant positive linear correlations between plant N and soil C, and plant and soil N (P < 0.01). Thus, the determination of C, N, and P stoichiometric characteristics of plant-soil-microbe interactions in the present study showed that in karst ecosystems, croplands were more limited by N than by P, whereas artificial pastures in rehabilitated land were mainly limited by P, especially during the vigorous restoration stage. Plant C:N:P stoichiometric characteristics in pastures at different ages showed a higher temporal variability than those of soil. 参考文献 相似文献 引证文献

Spatio-Temporal Variation and Impact Factors for Vegetation Carbon Sequestration and Oxygen Production Based on Rocky Desertification Control in the Karst Region of Southwest China

The Grain to Green Program (GTGP) and eco-environmental emigration have been employed to alleviate poverty and control rocky desertification in the Southwest China Karst region. Carbon sequestration and oxygen production (CSOP) is used to indicate major ecological changes, because they involve complex processes of material circulation and energy flow. Using remote sensing images and weather records, the spatiotemporal variation of CSOP was analyzed in a typical karst region of northwest Guangxi, China, during 2000–2010 to determine the effects of the Chinese government’s ecological rehabilitation initiatives implemented in 1999. An increase with substantial annual change and a significant increase (20.94%, p &lt; 0.05) in variation were found from 2000 to 2010. CSOP had a highly clustered distribution in 2010 and was correlated with precipitation and temperature (9.18% and 8.96%, respectively, p &lt; 0.05). CSOP was significantly suppressed by human activities (p &lt; 0.01, r = −0.102) but was consistent with the intensity of GTGP (43.80% positive). The power spectrum of CSOP was consistent with that of the gross domestic product. These results indicate that ecological services were improved by rocky desertification control in a typical karst region. The results may provide information to evaluate the efficiency of ecological reconstruction projects.

Soil erosion rates in two karst peak-cluster depression basins of northwest Guangxi, China: Comparison of the RUSLE model with 137Cs measurements

Reliable estimation of erosion in karst areas is difficult because of the heterogeneous nature of infiltration and sub-surface drainage. Understanding the processes involved is a key requirement for managing against karst rock desertification. This study used the revised Universal Soil Loss Equation (RUSLE) to estimate the annual soil erosion rates on hillslopes and compared them with 137Cs budget in the depressions at two typical karst peak-cluster depression basins in northwest Guangxi, southwestern China. Runoff plots data were used to calibrate the slope length factor (L) of the RUSLE model by adjusting the accumulated area threshold. The RUSLE model was sensitive to the value of the threshold and required DEMs with 1m resolution, due to the discontinuous nature of the overland flow. The average annual soil erosion rates on hillslopes simulated by the RUSLE were 0.22 and 0.10Mgha−1y−1 during 2006 through 2011 in the partially cultivated GZ1 and the undisturbed GZ2 basins, respectively. The corresponding deposition rates in the depressions agreed well with the 137Cs records when recent changes in precipitation and land use were taken into consideration. The study suggests that attention should be given to the RUSLE-L factor when applying the RUSLE on karst hillslopes because of the discontinuous nature of runoff and significant underground seepage during storm events that effectively reduces the effects of slope length.

Modeling daily reference ET in the karst area of northwest Guangxi (China) using gene expression programming (GEP) and artificial neural network (ANN)

Nonlinear complexity is a characteristic of hydrologic processes. Using fewer model parameters is recommended to reduce error. This study investigates, and compares, the ability of gene expression programming (GEP) and artificial neural network (ANN) techniques in modeling ET0 by using fewer meteorological parameters in the karst area of northwest Guangxi province, China. Over a 5-year period (2008–2012), meteorological data consisting of maximum and minimum air temperature, relative humidity, wind speed, and sunshine duration were collected from four weather stations: BaiSe, DuAn, HeChi, and RongAn. The ET0 calculated by the FAO-56 PM equation was used as a reference to evaluate results for GEP, ANN, and Hargreaves models. The coefficient of determination (R 2) and the root mean square error (RMSE) were used as statistical indicators. Evaluations revealed that GEP, and ANN, can be used to successfully model ET0. In most cases, when using the same input variables, ANN models were superior to GEP. We then established ET0 equations with fewer parameters under various conditions. GEP can produce simple explicit mathematical formulations which are easier to use than the ANN models.

How ecological restoration alters ecosystem services: an analysis of vegetation carbon sequestration in the karst area of northwest Guangxi, China

Ecological restoration, which aims to restore disturbed ecosystems, has been an important approach to mitigate human pressures on natural ecosystems and to improve ecosystem services. Determination of the vegetation carbon effect requires the assessment of ecological restoration measures. In this study, the temporal-spatial characteristics of vegetation carbon services were analyzed using remote sensing data and weather parameters by using geographic information system in northwest Guangxi, China, a typical karst area covered by the ongoing China’s Grain-to-Green Program and eco-environment immigration during 2000–2010. The results showed that ecosystem services of vegetation carbon sequestration showed an upward trend during the 11 years; approximately 21.14 and 18.09 % of the karst area showed significant changes in the net primary productivity (NPP) and net ecosystem productivity (NEP; P < 0.05), respectively. With regard to spatial distribution, NPP and NEP were higher for the western non-karst areas, and the greatest increase in these parameters was recorded in the eastern part of the restoration area of karst rocky desertification. Vegetation carbon sequestration was significantly affected by the impacts of vegetation coverage, vegetation species, and forest type. The results of this study suggested that rocky desertification control measures have positive impacts on the spatial distribution of vegetation carbon services in the typical karst area of northwest Guangxi, China.

Stoichiometric characteristics of plants, litter and soils in karst plant communities of Northwest Guangxi

探明我国西南喀斯特生态脆弱区植被恢复重建背景下，森林植物、凋落物与土壤碳（c）、氮（N）、磷rP）化学计量特征有助于深入地认识喀斯特森林生态系统养分循环规律和系统稳定机制。该文选取桂西北典型喀斯特地区域3个原生林群落和3个自然恢复28年的次生林群落，研究其“植物．凋落物一土壤”连续体的C、N、P化学计量学特征及其内在关联。结果表明：11圆果化香树（Platycarya longipes）、伞花木（Eurycorymbus cavaleriei）和青檀（Pteroceltis tatarinowiO以及圆叶乌桕（Sapium rotun-difolium）、八角枫（Alangium chinense）和黄荆（Vitex negundo）6种植物的C、N、P平均含量分别为427．5、21．2、1．2mg．g^-1；凋落物C、N、P平均含量分别为396．2、12．7、0．9mg·g^-1，而表层土壤（0-10cm）C、N、P平均含量分别为92．0、6.35和1．5mg·^-1。2）原生林N再吸收率（平均值为42．7％）高于次生林（平均值为36．5％），P再吸收率（20．4％）显著低于次生林（32.3％）（P〈0．05）；6个森林群落N的再吸收率均大于P的再吸收率。3）不同群落凋落物的C：N值差异不显著，原生林植物的C：N值小于次生林、土壤C：N显著大于次生林；原生林土壤C：P与次生林无显著差异，植物与凋落物C：Pdx于次生林；原生林凋落物与土壤N：P值小于次生林，植物N：P比平均值均为17．4。4）研究区典型森林群落植物中N和P含量呈显著的正相关关系，植物C：N与N：P、C：P与N：P比值均无明显相关关系；经过对数变换后的土壤C：N与N：P呈显著负相关关系，凋落物的C：P与N：P值呈极显著正相关关系。研究结果可为我国西南典型喀斯特脆弱生态区的生态功能恢复与植被重建提供科学依据。

Comprenhensive Prospecting Prediction of the Shijia Gold Deposit in Northwest Guangxi, China

Acta Geologica Sinica - English EditionVolume 88, Issue s2 p. 1334-1336 Meeting Abstracts Comprenhensive Prospecting Prediction of the Shijia Gold Deposit in Northwest Guangxi, China Yequan ZHOU, Yequan ZHOU Guangxi Key Laboratory of Concealed Metallic Mineral Exploration, Gulin University of TechnologySearch for more papers by this authorBaocheng PANG, Corresponding Author Baocheng PANG Guangxi Key Laboratory of Concealed Metallic Mineral Exploration, Gulin University of TechnologyCorresponding author. E-mail: 344026863@qq.comSearch for more papers by this authorYoubin CHEN, Youbin CHEN Guagnxi Bureu of Geology, Mineral Prospecting and ExploitationSearch for more papers by this authorYuandong LIU, Yuandong LIU Zhejiang Institute of Geological SurveySearch for more papers by this author Yequan ZHOU, Yequan ZHOU Guangxi Key Laboratory of Concealed Metallic Mineral Exploration, Gulin University of TechnologySearch for more papers by this authorBaocheng PANG, Corresponding Author Baocheng PANG Guangxi Key Laboratory of Concealed Metallic Mineral Exploration, Gulin University of TechnologyCorresponding author. E-mail: 344026863@qq.comSearch for more papers by this authorYoubin CHEN, Youbin CHEN Guagnxi Bureu of Geology, Mineral Prospecting and ExploitationSearch for more papers by this authorYuandong LIU, Yuandong LIU Zhejiang Institute of Geological SurveySearch for more papers by this author First published: 29 December 2014 https://doi.org/10.1111/1755-6724.12380_56Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume88, Issues2Special Issue: Meeting Abstracts: The 14th Quadrennial International Association on the Genesis of Ore Deposits Symposium. August 19–22, 2014, Kunming, ChinaDecember 2014Pages 1334-1336 RelatedInformation

Comprehensive Information Metallogenic Prospectingon Carlin‐type Gold Deposits in Northwest Guangxi

Comprehensive Information Metallogenic Prospectingon Carlin‐type Gold Deposits in Northwest Guangxi

Modeling soil erosion using a spatially distributed model in a karst catchment of northwest Guangxi, China

ABSTRACTReliable assessment of the spatial distribution of soil erosion is important for making land management decisions, but it has not been thoroughly evaluated in karst geo‐environments. The objective of this study was to modify a physically based, spatially distributed erosion model, the revised Morgan, Morgan and Finney (RMMF) model, to estimate the superficial (as opposed to subsurface creep) soil erosion rates and their spatial patterns in a 1022 ha karst catchment in northwest Guangxi, China. Model parameters were calculated using local data in a raster geographic information system (GIS) framework. The cumulative runoff on each grid cell, as an input to the RMMF model for erosion computations, was computed using a combined flow algorithm that allowed for flow into multiple cells with a transfer grid considering infiltration and runoff seepage to the subsurface. The predicted spatial distributions of soil erosion rates were analyzed relative to land uses and slope zones. Results showed that the simulated effective runoff and annual soil erosion rates of hillslopes agreed well with the field observations and previous quantified redistribution rates with caesium‐137 (137Cs). The estimated average effective runoff and annual erosion rate on hillslopes of the study catchment were 18 mm and 0.27 Mg ha−1 yr−1 during 2006–2007. Human disturbances played an important role in accelerating soil erosion rates with the average values ranged from 0.1 to 3.02 Mg ha−1 yr−1 for different land uses. The study indicated that the modified model was effective to predict superficial soil erosion rates in karst regions and the spatial distribution results could provide useful information for developing local soil and water conservation plans. Copyright © 2014 John Wiley &amp; Sons, Ltd.

Soil organic carbon and nutrients content at different land use types in the karst region of Northwest Guangxi

Soil organic carbon and nutrients content at different land use types in the karst region of Northwest Guangxi