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A Study on Forest Species Diversity and Its Ecological Service Function in the Plateau Area of Western Sichuan

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Wuhan University Journal of Natural sciences 2003年第3B期8卷 975-980页

作者： Deng Yu-lin, Wang Yu-kuan, Peng Pei-haoInstitute of mountain hazards and environment,{3., chengdu 610041, Sichuan, china Institute of mountain hazards and environment Chinese Academy of Sciences Chengdu 610041 SichuanChina

This paper presents a study on species diversity and its ecological service function in the plateau area in western Sichuan. The results show that species diversity in the plantations on the cutover land has a tendency to increase and that its ecological service function is to be improved with stand age growing. The species diversity in forest communities is also gradually increased on different succession stage till reaching a climax level. But the species diversity in the climax community is slightly decreased before it reaches a relatively constant status. Ecological service function of diversity is gradually strengthened with the progress of succession. In addition, species diversity in a stand in a similar site and at a same age differs among forest types. Species diversity index within a coniferous and broad-leaved mixed forest is larger than that within a coniferous forest. Meanwhile, species diversity enriches as the tree density increases.

关键词： bio-diversity ecological service function plateau area western Sichuan

A Soil Temperature Control System for Sapling Study in Alpine Region

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Journal of mountain Science 2011年第5期8卷 739-749页

作者： CHENG Song ZHANG Li SONG Hongtao YU Hui GeCheng Global Eco-Tech Inc. 988 Dodridge Road Columbus Ohio 43200 USA Olentangy River Wetland Research Park The Ohio State University 352 Dodridge Road Columbus Ohio 43202 USA Institute of mountain hazards andenvironment ChineseAcademy of Seiences #9 Block 4 Renminnanlu Road Chengdu 610041 China Graduate University of chinese academy of sciences Beijing 100049 China

A soil temperature control system was designed for sapling study in alpine region and tested in summer, 2009. The system consisted of a power switch, voltage regulator, microcomputer timer, safety relays, temperature control device, temperature sensors, heating cables, fireproofing plastic pipes (PVC), 108 heavy-duty plastic containers and seedlings. The heating cables were held in six 2-layer PVC frames with 25 cm wide, 3.0 cm long and 25 cm high and three 1-layer frames with 25 cm wide and 3.0 cm long for 15°C soil temperature treatment, half of the 2-layer frames were used for 20°C and 25°C soil temperature treatments, respectively. Each of the frames was installed at each of ditches with 3. cm wide, 3.0 cm long and 3. cm deep in size. 12 seedling containers with 20 cm top diameter, 18cm bottom diameter and 25 cm high were homogenously placed at each of the ditches, and spaces between the containers were filled with natural soil. The system was economic, and could increase soil temperatures obviously and uniformly, the maximal and minimal standard errors of soil temperatures were ±0.28 and ±0.05°C at 10cm depth in the containers within each of all the ditches. In the system, aboveground environment was natural, diurnal and monthly soil temperatures varied with changing air temperature, the research results may be better to know the eco-physiological and growth responses of alpine saplings/seedlings to soil warming than that in greenhouse, laboratory, infrared heat lamp and open top chamber.

关键词： Alpine mountain Eco-physiology Seedling growth Soil temperature Control system

Tillage Pedogenesis of Purple Soils in Southwestern china

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Journal of mountain Science 2009年第2期6卷 205-210页

作者： HE Xiubin BAO Yuhai NAN Hongwei XIONG Donghong WANG Li LIU Yanfeng ZHAO Jingbo Institute of mountain hazards and environment Chinese Academy of Sciences Chengdu 610041 China Graduate School of the chinese academy of sciences Beijing 100049 China Shaanxi Normal University Xi'an 710062 China

Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO Taxonomy or Entisols in USDA Taxonomy, are formed from purple rocks of the Trias- Cretaceous system, have been developed or at least accelerated the development due to continual tillage operation, especially digging and ridging. The present study took micromorphological investigation on the sedimentary rocks and the soils under different operations of tillage. Results show that the purple rock of Feixiangguan Formation of the Trias system （Tlf） is the easiest to physical weathering and the most fertile soil material enriched in nutrients, and it has been, therefore, mostly cultivated and intensively tilled around the year. It has the fastest soil formation rate. Soil formation rate in the cropland with conventional tillage is higher than that in the forestiand and the grassland. It implies that the artificial brokenness and tillage disturbance play a great role in physical weathering and initiating soil formation processes.

关键词： Tillage impact pedogenesis purple soil micromorphology southwestern china

A New Process Study on Comprehensive Utilization of NOx from Nitric Acid Plant

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Wuhan University Journal of Natural sciences 2003年第S2期 1001-1006页

作者： Zhou Hou-zhen, Liang Hua Institute of mountain hazards and environment,{3., chengdu 610041, Sichuan, china Southwest Institute of Technical Physics, chengdu 610041, Sichuan, china

Based on studies of controlling NOx from nitric acid exhaust gas domestic and abroad, this paper has developed a new technique on removal of NOx and production of aby-product with high added value-MnO2. Experimentshows, pyrolusite, whose valid composition is MnO2 , of absorbing NOx has the following characteristics: quick, low cost, no secondary pollutant. Moreover, exhaust gas can attain the required standards. If the temperature of the pyrolusite serum is 3.℃ , pH = 4, containing 90 g/L MnO2, the absorptivity for 3.000 mg/m3.NOx is 89. 2%. Furthermore, few of the impurities in pyrolusite dissolve in the absorption mother solution. The purification cost of product is very low. The purity of end product MnO2 is more than 99. 995% after purifying. Therefore, it is workable for the new technique on economy and technology. There are also obvious environmental benefits and marked economic returns.

关键词： NOx nitric acid exhaust gas comprehensive utilization pyrolusite MnO2

Impact of the Small Town Construction on Original Inhabitants in the Three Gorges Reservoir Area——A Case Study in Lishu Village, Changling Town, Chongqing Municipality, china

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Wuhan University Journal of Natural sciences 2003年第3B期8卷 897-904页

作者： Liu Shao-quan, Chen Guo-jie, Chen Zhi-jianInstitute of mountain hazards and environment,{3., chengdu 610041, Sichuan, china Institute of mountain hazards and environment Chinese Academy of Sciences Chengdu 610041 SichuanChina

Based on the five-year long dynamic tracking and investigation of the peasant households of the Lishu village, the influences by small town construction on the economy and employment of the original peasant households are discussed. On the one hand, small town construction plays a positive role in adjustment of the industrial structure of the original peasant households and in the transfer of their employment towards non-agricultural industries. On the other hand the economic growth of the original peasant households is not so well sustainable, and is so fluctuating. Moreover, the unbalance of income distribution of the said households has been furthered, and small town construction has made the existing labor surplus of the original peasant households more serious, particularly the women labor surplus.

关键词： the Three Gorges reservoir area small town construction original inhabitant economic income employment

Rural Public Investment and Benefit in Sichuan's Hilly and mountainous Areas

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Asian Agricultural Research 2012年第8期4卷 28-32页

作者： ZHANG Hai-qin 1,3.,LIU Shao-quan 1 ,LUO Ren-fu 2 ,ZHANG Lin-xiu 2 1. Institute of mountain hazards and environment,{3. academy of sciences,chengdu 610041,china 2. Institute of Geographic sciences and Natural Resources Research,{3. academy of sciences,Beijing 100101,china 3. Graduate University of chinese academy of sciences,Beijing 100049,china

Using representative sampling survey data,we take the case of roads,domestic water,irrigation facilities,clinics and schools,to give an overview of the status quo of rural public investment in Sichuan's hilly and mountainous areas in the period 2005 -2008; conduct comprehensive analysis of public investment benefit,from the status quo of supply and demand,social benefit and villagers' satisfaction. The results show that the social benefit arising from the construction of road projects is good,while the social benefit arising from the construction of irrigation facilities is poor; the matching effect of supply and demand of public investment is poor,especially for the investment in irrigation facilities; on the whole,villagers' satisfaction with public investment has been promoted,but most of the villagers are still unsatisfied with the current irrigation facilities. The major capital source of rural public investment is from the government,but from the perspective of the villagers' demand,we should further increase the public financial input.

关键词： Rural public investment Social benefit index Evalu

A Preliminary Study on 1D Numerical Experiment of Water Debris Flow in Gully

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四川大学学报（工程科学版） 2005年第S1期37卷 143-147页

作者： LIU Tonghuan~1 WANG Xiekang~1 CUI Peng~2 (1.State Key Lab.of Hydraulics and mountain River Eng.,Sichuan Univ.,chengdu 610065,china 2.Inst.of mountain hazards and environment,chinese academy of Sci.,chengdu 610041,china)

In order to improve and enhance the numerical modeling methods and its application on debris flow problems,a preliminary study has been proposed in accordance with the corrected water-sediment numerical model on the premise of revised resistance and sediment capacity ***,an overview the recent re- search achievements on numerical simulation of debris flow has been conducted,the results shown that a gener- al numerical model for debris flow can not be existed at all because the complex rheol...

关键词： Water debris flow Saint-Venant equation Numerical experiment

A New Treatment of Depression for Drainage Network Extraction Based on DEM

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Journal of mountain Science 2009年第4期6卷 311-319页

作者： WANG Yan PENG Hong CUI Peng ZHANG Wanshun QIAO Fei CHEN Cai'er School of Resource and environmental Science Wuhan University Wuhan 430079 China College of Water Resources and Hydropower Engineering Wuhan University Wuhan 430072 China Institute of mountain hazards and environment Chinese Academy of Sciences Chengdu 610041 China chinese academy of environmental {3. Beijing 100012 China

Depressions in landscapes function as buffers for water and sediment. A landscape with depressions has less runoff, less erosion and more sedimentation than that without depressions. Sinks in digital elevation models （DEMs） can be considered the real features that represent depressions in actual landscapes or spurious features that result from errors in DEM creation. In many hydrological and erosion models, all sinks are considered as spurious features and, as a result, these models do not deal with the sinks that represent real depressions. Consequently, the surface runoff and erosion are overestimated due to removing the depressions. Aiming at this problem, this paper presents a new method, which deal with the sinks that represent real depressions. The drainage network is extracted without changing the original DEM. The method includes four steps： detecting pits, detecting depressions, merging depressions, and extracting drainage network. Because the elevations of grid cells are not changed, the method can also avoid producing new fiat areas, which are always produced by the conventional filling methods. The proposed method was applied to the Xihanshui River basin, the upper reach of the Jialingjiang River basin, china, to automatically extract the drainage network based on DEM. The extracted drainage network agrees well with the reality and can be used for further hydrologic analysis and erosion estimation.

关键词： Drainage network extraction Depression processing Digital elevation model Wooden barrel effect Xihanshui River basin.

UNCERTAINTY ANALYSIS ON ZONATION MAPS OF DEBRISFLOW HAZARD IN YUNNAN PROVINCE,china

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chinese Geographical Science 2000年第2期10卷 138-143页

作者： LIU Xi-lin(Dapartment of Urban and environmental Scicnces, Peking University Beijing 100871, P.R.china Institute of Moun tain hazards and environment, the chinese academy of Sicnces, chengdu 610041,P.R.china) Department of Urban and environmental sciences Peking University Beijing P. R. China Institute of mountain hazards and environment the Chinese Academy of Sciences Chengdu P. R. China

Different researchers select different factors and use different methods to assess the regional hazard degrees of debris now. consequenily, even for the same region, tb.. are often different hazard zonation maps, and there must be some uncertainty in the zonations. Thus the ceriainty analysis of zonation maps becomes obviously *** debris now hazard, those zonation maps with a certainty analysis could provide most valuable information for land users, hazard managers and policy makers. By comparison of three researchers’ findings in Yunnan Province, this paPer shows that seven to nine iafluential factors are chosen for the zonation maps. spatial density of debris flow ravines,regional average rock-weathering coefficient, yearly precipitation, days of≥50 mm daily rainfall, and proportion of sloping land with slope≥25℃to the total land are the most acceptable factors. Mathemahcal methods of maximum-minimumvalues, upperlower limit values and Fuzzy values are used to quantify the factors. Step-by-step methodoogy is commonly used for the zonation maps. Research results show that mchmum uncedrinty is 66. 6% and minimum uncertainty is 3..7% in debris now hazard maps of zhaotong Prefecture and Yunnan Province. Therefore there is still much work for us to improve the zonation methedology.

关键词： debris flow hazard zonation uncertainty zonation map