Simulating potential vegetation distribution in a mountainous region of the Eastern Tibetan Plateau:A case study of Barkam County

The main objective of this study is to simulate the potential vegetation types on the basis of environmental parameters.The paper took Barkam County in a mountainous region of the Eastern Tibetan Plateau as the study area.The vegetation distribution was mapped in 1994 and 2007 based on TM remote sensing images by object-oriented interpretation method.We overlaid the two maps to find out the vegetation patches which have not changed,and took them as stable types.Fifty per cent of the stable patches were randomly sampled to operate the logistic regression with related environmental parameters;others were used as test data of simulated results.Seven environmental parameters were mapped,including elevation,slope,aspect,surface curvature,solar radiation,temperature and precipitation,based on DEM data and meteorological site data by GIS technology.The relationship between the spatial distribution of vegetation and environmental variables were quantified by logistic regression.The distribution probabilities of each vegetation type were calculated.Finally,the spatial distribution of potential vegetation was simulated.This research can provide a scientific basis for vegetation restoration and ecological construction in this area.     

近40年青藏高原湖泊环境变化遥感分析研究

利用高分一号多光谱影像,提取高原上面积大于1 km2的湖泊,并结合两次全国湖泊调查数据集及气象资料,对1975年至2015年湖泊变化及其环境影响因素进行分析。研究结果表明：2015年青藏高原1 km2以上湖泊个数共计1210个,自1975年以来整体呈扩张趋势;雅鲁藏布江流域由于蒸发量的增大湖泊面积呈下降趋势;西藏内流区由于降水量的增加、蒸发量的减少和温度升高引起冰川融化,导致湖泊面积持续扩张。为青藏高原湖泊变化及对环境气候波动的响应等研究提供参考。     

Spatial and temporal patterns of soil erosion in the Tibetan Plateau from 1984 to 2013北大核心CSCD

Soil erosion has a critical effect on ecological security and socioeconomics, which may deteriorate ecosystem services and common human well-being. The revised universal soil loss equation (RUSLE) was applied to assess soil erosion from 1984 to 2013 in the Tibetan Plateau and analyzed the temporal and spatial variation of soil erosion intensity. Furthermore, the temporal and spatial variation rates of soil erosion were explored across different ecosystems. The results indicated that the annual soil erosion fuctuated in the Tibetan Plateau, the soil erosion intensity decreased from south to north, and the most serious soil erosion was mainly distributed in the southern Tibetan Plateau (Xigaze and Changdu regions, Lhasa, and north of the Shannan region). The soil erosion intensity was higher in shrub, alpine meadow, and sparse vegetation ecosystems. The highest soil erosion was found in alpine meadow (2.17 × 1010 t), followed by alpine grassland (1.59 × 1010 t) and sparse vegetation (1.30 × 1010 t) ecosystems. Meanwhile, although the most serious soil erosion intensity was found in the regions of 3 000-4 000 m altitude, the soil erosion was mainly observed in the regions of 4 000-5 000 m altitude. In the three most recent decades, annual soil erosion decreased at a rate of-1.78 × 108 t/a. Additionally, soil erosion mainly increased in south of the Qiangtang Plateau and in the periphery of the Qaidam basin. Decreased soil erosion was mainly found along the Hengduan Mountains, central Himalayas. Although the increased annual normalized difference vegetation index (NDVI) had positive effects for soil protection, changes in soil erosion was mainly controlled by the change of annual precipitation. Thus, the fragility of ecological systems and increased rainfall erosivity accounted for the obviously increased soil erosion in the alpine grassland ecosystem (1.19 × 10 t/a). However, increased ecosystem stability and decreased rainfall erosivity contributed to the decreased soil erosion in forest and shrub ecosystems, by-0.77 × 10 t/a and-1.65 × 10 t/a, respectively. The slightly decreased rainfall erosivity accounted for a decrease of soil erosion in the sparse vegetation ecosystem (-0.44 × 10 t/a). Meanwhile, soil erosion has decreased in the alpine meadow ecosystem over the past 30 years, which may owing to the relatively higher NDVI that neutralized the increase of rainfall erosivity to some extent. This study revealed serious soil erosion regions and ecosystems in the Tibetan Plateau and explored possible reasons for variations in soil erosion in different ecosystems, which may provide a scientific reference for soil erosion conservation and control in the near future. © 2018 Science Press. All rights reserved.     

日本新潟县中越大地震震害调查及分析

2004年10月23日，日本新潟县中越地区发生里氏6．8级强烈地震，死亡40人，受伤4500余人，10万余人无家可归；房屋损坏近14万栋，财产损失约3万亿日元。作者随日本建筑学会地震考察队到该次地震现场进行了考察，报告主要内容包括：地震概况，地震活动性、地震烈度分布及地震波的特征，震害及分析，经济损失，最后给出了这次地震的震害经验和教训。内容可供建筑抗震设计和今后有关规范的修订参考。     

简论藏族聚居区可持续发展与产业结构调整导向

我国藏族人口聚居区由于受资源—环境、劳动力素质和经济发展水平等因素限制,只能选择兼顾经济—生态环境综合效益的可持续发展道路。为此,作者提出了重点开发藏区旅游服务及其相关第三产业,实现产业结构良性调整,建立具有藏区特色的新型产业结构的有关建议与构想。     

浅析新疆博斯腾湖的生态旅游

博斯腾湖是全国最大的内陆淡水湖，是新疆南疆地区经济发展和人民生活的主要水源，也是塔里木河下游生态应急输水的直接水源，同时，博斯腾湖还是当地著名的旅游风景区。因此，在发展当地旅游业的同时，要兼顾博斯腾湖的生态环境，实现生态环境与经济发展“双赢”的目的，而要实现这个目的的关键在于如何在当地开展生态旅游。     

念青唐古拉山扎当冰川雪冰中不溶性有机碳含量及其辐射强迫研究

为了研究雪冰中不溶性有机碳(Water-insoluble Organic Carbon,WISOC)的含量及其辐射强迫作用,于2012年7月和8月对青藏高原南部纳木错流域扎当冰川90个表层雪冰样品中WISOC的含量进行了分析,采样期间利用地物光谱仪实地测量了反照率.结果表明,在消融季节(7—8月),扎当冰川表面被裸冰、老雪和新雪覆盖,以上3种消融情形下WISOC的平均含量分别为(1618.4±1236.0)、(432.3±329.7)和(183.7±158.0)ng·g-1,雪冰的融化导致WISOC等吸光性物质在冰川表面的富集,降低了冰川表面反照率.通过SNICAR模型(Snow,Ice,and Aerosol Radiative Modle)敏感性分析表明,3种情形下WISOC降低雪冰表面反照率(贡献率)分别为0.0020(6.8%)、0.0018(7.4%)和0.0010(2.1%),对应的WISOC的辐射强迫分别为1.14、1.34和0.81 W·m-2.平均地,WISOC对辐射强迫的影响超过了黑碳(BC)影响的20%,而在新雪覆盖条件下,WISOC对辐射强迫的影响甚至达到了粉尘影响的72.3%.因此,虽然雪冰中的WISOC的吸光能力相对于BC较弱,但所引起的雪冰表面反照率降低及冰川消融等效应不容忽视.     

青藏高原土壤有机碳密度垂直分布研究

通过对青藏高原土壤普查数据的整理分析,定量研究了青藏高原28个典型土壤类型、14个主要生态系统类型0～20cm、20～50em及50～100cm深度内土壤有机碳密度的垂直分布规律.结果表明,青藏高原28个典型土壤类型3个土层的有机碳密度平均值为(6.16±1.08)kg·m-2、(5.06 ±0.85)kg·m-2、(5.30±0.82)kg·m-2;在0～100cm土层内,暗棕壤、沼泽土的有机碳密度显著高于其它土壤类型,而高山漠土、灰棕漠土、亚高山漠土的有机碳密度不仅远远低于区域平均水平,而且显著低于其它土壤类型.14个典型生态系统土壤的有机碳密度均值为(7.47±1.38)kg·m-2、(6.07±1.24)kg·m-2、(6.46±1.16)kg·m-2;其中,以沼泽草甸、针叶林土壤的有机碳密度最高,而温性荒漠、高寒荒漠、高寒草原及亚高山草原土壤有机碳密度显著低于其它生态系统.这不仅体现了青藏高原土壤-植被显著的地带性分布,而且为青藏高原土壤有机碳循环模型,及有机碳对全球变化的响应研究提供重要的基础数据.     

Environmental status and management in Chiba Prefecture

Chiba Prefecture is located in the east of Tokyo Metropolis. A large scale development of industrial and residential areas began in the late 1950s until then the main industries of the prefecture were agriculture and fisheries. During the past 30 years rapid industrialization and urbanization took place resulting in occurrence of various environmental problems.In an attempt to establish a better environment condition towards 21st century Chiba Prefecture has made Environmental Plan which all the municipal governments, enterprises and inhabitants should observe to realize better environment.     

基于贫困识别和精准帮扶的种植业产业效率——来自家庭微观数据的证据

产业帮扶是精准扶贫的重要内容,贫困识别及精准帮扶对扶贫产业效率的影响值得深入研究。基于重庆市石柱土家族自治县534个农户的调研数据,运用经典统计学分析框架检验了贫困识别和精准帮扶后村域之间及农户之间的种植业产业效率差异,并分析了差异形成的关键因素。结果表明：（1）贫困识别及精准帮扶显著促进了种植业产业效率的提高,贫困村的效率绝对值高于非贫困村,脱贫户的效率绝对值高于贫困户;（2）政策因素是造成贫困村与非贫困村、贫困户与脱贫户之间种植业效率差异显著的关键因素,其中,道路等基础设施建设及特色种植业对贫困村、脱贫户的影响尤为突出;（3）年龄对贫困地区种植业产业效率的影响呈现“U”型趋势,55~60岁属于产业效率提升的拐点;（4）高中及以上教育水平会促进种植业产业效率的提高,但农户仅具有不等年限的义务教育阶段受教育水平对其效率提升作用不明显。建议继续实施产业帮扶政策并建立绩效考核长效机制,确保贫困人口经济收入的稳步增长,缓解贫困村与非贫困村及贫困户与非贫困户间发展失衡的矛盾;提升贫困地区农业劳动力的人力资本水平可以提高扶贫产业效率。