The Features of the Ecological Environment and Protective Solutions along the Qinghai-Tibet Railway

On29June,2001aninaugurationceremonyfortheQuinghai TibetRailway,aprojectattractingworldwideattention,washeldsimultaneouslyattheCityofGolmudinQinghaiprovince,andtheCityofLhasainTibetAutonomousRegion,indicatingthattheconstructionofthesectionfromGolmudtoLhasaoftheQinghai TibetRailwaywasfullytocarryout.ThePlateauofQinghai Tibethasaveryfragileecologicalenvironment.ThestategaveprioritytotheissueoftheecologicalenvironmentalprotectionintheconstructionoftheQinghai TibetRailway.PresidentJiangZh…     

Study on the Technology of Restoration and Giving a New Lease of Life to the Alpine Grassland Vegetation in the Construction of the Qinghai-Tibet Railway

This article gives a summary and analasis to experimental study on the restoration and giving a new lease of life to the alpine grassland vegetation along the Qinghai-Tibet Railway. Through on-the-spot investigation and vegetaion storation experimental study to the constructive fetching soil ground in Tuotuo River experiment section in the construction of the Qinghai-Tibet Railway, the result shows ： after the activities of the construction, soil conditions on the fetching soil ground have changed a lot, the soil quality has obviously degraded. In order to do well the vegetaton storation and reconstruction in the process of the construction of the Qinghai-Tibet Railway, the backfilling of the surface soil should really be done well. According to the result of on -the-spot experiment, the Elymus dahuricus Turcz and Poa annua Linn are all more suitable to the fetching soil environment on the alpine grassland, the plant can normally grow in the growing season. The timing selection of the vegetation should fully use feature of both rain and heat in the same season, thus can improve the percentage of success.     

GIS-Based Spatial Analysis and Modeling for Landslide Hazard Assessment： A Case Study in Upper Minjiang River Basin

By analyzing the topographic features of past landslides since 1980s and the main land-cover types （including change information） in landslide-prone area, modeled spatial distribution of landslide hazard in upper Minjiang River Basin was studied based on spatial analysis of GIS in this paper. Results of GIS analysis showed that landslide occurrence in this region closely related to topographic feature. Most areas with high hazard probability were deep-sheared gorge. Most of them in investigation occurred assembly in areas with elevation lower than 3 000 m, due to fragile topographic conditions and intensive human disturbances. Land-cover type, including its change information, was likely an important environmental factor to trigger landslide. Destroy of vegetation driven by increase of population and its demands augmented the probability of landslide in steep slope.     

Discussion on Landscape Ecosystem Planning of Small Basins in the Qinghai.Tibet Plateau——Taking Nieruzangbu Basin as an Example

In this paper, taking Nieruzangbu as an example, it is discussed that how to plan landscapes of small basin in the Qinghai-Tibet Plateau. With analyzed the status and character of landscape structure through the use of landscape diversity indexes and landscape dominant indexes, some major problems in the landscape ecosystem are pointed out. On the basis of regional restrictive principle and compliance principle of resources, environment and economy, Nieruzangbu Basin is divided into three landscape function areas. According to the demands of each function area, landscape structure planning is carried out to improve ecological environment through optimization and adjustment of landscape structure in Nieruzangbu Basin.     

Analysis on Landscape Pattern in the Upper and Middle Reaches of Yarlung Zangbo River：Taking Zhongba County, Angren County, Rikaze City as Example

Taking Zhongba County, Angren County, Rikaze City located at the Upper and Middle Reaches of Yarlung Zangbo River as landscape units , this paper studied the difference of the landscape pattern under various degrees of human disturbance in the three areas. The results showed that： the three areas all reflected the same characteristic of landscape pattern in Qinghai-Tibet Plateau, the natural landscapes were in the absolute dominant position. However, from Zhangba to Rikaze, with human disturbance intensity increasing, anthropogenic features of landscapes became more and more outstanding, In Zhongba, the landscape structure appeared to be simpler with coarse grains and a less rich diversity, Conversely, in Rikaze, the landscape showed a complicated shape with finer grains and a relatively richer diversity, This reflected that the impact of human activities to natural landscape behaved a gradually-growing trend from the upper reach to the middle one of Yarlung Zangbo River Basin.     

Effect of Land Use on Soil Properties in Debris Flow Bottomland： A Case Study at Xiaojiang Basin, Yunnan

In order to understand the effect of different land use on soil physics and nutrients properties of the debris flow bottomland, a case study at Daqing gully （in Xiaojiang Basin, Yunnan） was conducted in 2004. Soil samples were taken at depth of 0-10,10-20,20-40,40-60,60-80 cm under three land use patterns crop bottomland （CL）, forest bottomland （FL）, and barren bottomland（BL）. The results showed that the developing bottomland to CL promoted soil toaccumulate total phosphorus （TP） and available phosphorus （AP）, pH value transferred from neutral to alkalescency, and organic matter decreased significantly. Furthermore, the contents of total nitrogen （TN） and available nitrogen （AN） in CL were lower than that of FL and BL because the growth of crops consumed more nutrients in soil. The results also showed that the contents of TP, AP and available potassium （AK） in soil were positively correlated with soil particle.     

Ecological functions of ciliated protozoa in marine ecosystem： effects of ammonium on the population growth of Euplotes vannus

The effects of ammonium on the population growth of the marine ciliate, Euplotes vannus, were examined using ecotoxicological method, h is showed that ammonium exerts inhibitory effects on the growth of the ciliate populations in a concentration-dependent way. Statistical analvsis reveals that the population growth dynamics exposed to ammoniunt-N concentration over 100mg/L are significantly different from that in the control at P 〈 0.05 level. Linear regression determined that the 24h, 36h, 48h, 60h, 72h and 84h IC50 values of ammonium-N are 19.68, 201.51, 167.49, 47.86, 50.43 and 43.11 concentration over 100mg/L, respectively （ P 〈 0.05; pH 8.2; salinity 28 ppt; temperature, 25℃ ）. The results indicate that the tolerance to ammonium in E. vannus is considerably higher than that of the larvae or juveniles of some metozoa, such as cuhured prawns and oysters. Therefore, it is believed that the high tolerance to ammonium is necessary for eiliated protozoa to play positive roles in maintaining and improving water quality in marine ecosystems, especially in the intensive aquacuhure waters with high-level ammonium. In addition, the correlation between /C50 values and exposure time was discussed.     

Discussion on Landscape Ecosystem Planning of Small Basins in the Qinghai-Tibet Plateau-Taking Nieruzangbu Basin as an Example

In this paper, taking Nieruzangbu as an example, it is discussed that how to plan landscapes of small basin in the Qinghai-Tibet Plateau. With analyzed the status and character of landscape structure through the use of landscape diversity indexes and landscape dominant indexes, some major problems in the landscape ecosystem are pointed out. On the basis of regional restrictive principle and compliance principle of resources, environment and economy, Nieruzangbu Basin is divided into three landscape function areas. According to the demands of each function area, landscape structure planning is carried out to improve ecological environment through optimization and adjustment of landscape structure in Nieruzangbu Basin.     

Ecological Footprint and Ecological Security Evaluation in the Upper Min River Basin

On the basis of the ecological footprint (EF) model, this paper studied the ecological security in the Upper Min River Basin ecosystem. The result shows that with 2. 038 2hm^2 per capita ecological capacity (0.422 2hm^2 higher than per capita EF), and 165 825hm^2 ecology surplus, the ecosystem in Upper Min River is generally secure at present. But the arable land is overweighed and omens an ecosecurity crisis. Meanwhile, problems such as low forest coverage rate, severe loss of water and soil, enlargement of aridvalley area, frequent occurrence of mountain hazards and degradation of pastures have been major threats to the eco-security of this region. The calculation result of ten thousand-yuan (RMB) GDP shows that the use of natural resources is extensive, and there will be a rapid increase tendency of EF in the future. In order to maintain the present eco-security, the ways of use natural resources must be improved in the Upper Min River Basin.     

长江流域安徽段生态系统服务价值与景观生态风险时空演变及其关联分析

【目的】综合运用生态系统服务价值和景观生态风险评估,更好地为长江流域安徽段可持续发展提供决策支持,也为跨江区域生态环境管护提供一定参考。【方法】基于1995年、2005年和2015年安徽省土地利用数据,采用生态系统服务价值评估、景观生态风险评估和双变量空间自相关模型等方法,分析长江流域安徽段生态服务价值、生态风险时空变化及其关联特征。【结果】①1995—2015年研究区总生态系统服务价值呈减少趋势,减少率为0.54%;研究区以较高和中等生态服务价值等级为主,主要分布在长江沿岸、大别山区及皖南山区。②近20年长江流域安徽段生态风险整体呈升高趋势,以中、较低和低生态风险等级为主;空间上,较高和高风险区主要分布在长江沿岸及巢湖区域,并由集聚分布趋于连片扩张。③长江流域安徽段单位面积生态系统服务价值与生态风险之间存在空间正相关性,主要关系为高价值-高风险相关,即生态服务价值高的区域也是生态环境比较脆弱的区域,应特别关注。【结论】必须重视对湿地和林草景观的保护,加强以长江沿岸、巢湖区域为主的湿地生态保护和对大别山、皖南山区自然山体林草景观的保护与修复,将对提高长江流域安徽段生态系统服务功能和保护长江生态环境起着重要作用。     

晋江流域河道水库最小生态需水量计算研究

根据晋江流域的特点，对该地区改善河道水环境的生态需水量、保证山美水库水质达标的生态需水量以及满足河道生态用水比例，分剐采用径污比计算法、水体允许纳污量计算法进行了计算。得出了晋江流域东溪永春段的生态需水量为20．9～24．4m^3／s；东溪南安段的生态需水量为12．9～15．5m^3／s；西溪安溪段的生态需水量为23．8～38．8m^3／s；西溪南安的生态需水量为7．8～8．1m^3／s。综合考虑用水和需水两方面的情况，计算得到的晋江流域河道内生态用水比例值达30％以上。可满足河道内生态需水比例的要求，为保证山美水库水体水质达标，在现有排污量条件下，山美水库来水量应保证在2．0亿m^3。     

土地整理进程中镇赉项目区景观格局变化及生态风险

以吉林省镇赉县土地整理区为研究对象,通过获取土地整理前(2005年)和土地整理中(2009年)的土地利用遥感影像图,应用"3S"技术及景观指数计算软件建立了景观格局指标及生态风险评价指标,分析了研究区的景观格局变化和可能的生态风险,并在项目区进行了土壤盐碱化指标的定点监测.结果表明:研究区草地、旱田、盐碱地斑块数量和面积有不同程度的增加,湖泊和沼泽地面积减小;景观破碎度指数从0.366上升到0.382;项目区两种主要土地利用类型旱田和盐碱地优势度指数都呈现增加的趋势,景观生态风险值从2005年的0.73上升到2009年的1.08,生态风险仍处于极高级别.分析原因主要与近年来气候干旱、加之土地整理工程进度缓慢有关.项目区土壤定点监测显示,土地整理工程开始启动的北家子村土壤盐碱化得到了较明显的改善,土壤酸碱度、碱化度和总碱度都有不同程度的下降,而工程进度缓慢的前舍利村和后五家子村土壤质量变化不大.由此可见,加快研究区土地整理工作的进程是改善区域土壤质量和生态环境状况的重要措施.     

嘉陵江流域生态系统服务价值与生态风险时空分异特征及关联性

为嘉陵江流域及相关地区的生态环境保护和生态安全格局构建提供参考，基于2000、2010和2020年3期地表覆盖数据，应用生态系统服务价值(ecosystem service value，ESV)和生态风险指数(ecological risk index，ERI)评估模型、地理探测器、双变量空间自相关模型等方法，定量评估了嘉陵江流域ESV和ERI的时空演变、分异特征和关联性。结果显示：2000—2020年嘉陵江流域土地利用类型以林地和耕地为主，建设用地和水域增长迅速；研究期内流域ESV增长了1.50%，且高和极高等级单位面积ESV区域在流域内分布较广，水域面积增加是ESV增长的重要原因；研究期内流域ERI逐步降低，且极低和低等级ERI区域在流域内分布较广；人为影响指数与土地利用是ESV和ERI空间分异的主导因子；ESV和ERI具有统计学意义上的空间负相关性，主要关系为高价值-低风险，即ESV较高区域的ERI较低。推动土地利用结构优化，合理控制城镇建设规模，加强林地和水域保护力度，对嘉陵江流域生态服务功能提升和生态安全格局构建具有深远意义。     

黄河流域生态环境变迁的主导因素分析

1万年以来黄河流域生态环境发生了很大的变化，早期由亚热带森林草原景观演变为温带森林草原景观，后期森林草原景观逐渐被破坏，演变为现今天然植被几乎荡然无存，水土流失十分严重．黄河流域生态环境变迁的主导因素是气候和人类活动．气候自然波动是生态环境演变的基础，在冷干或暖干条件下，植被退化甚至死亡．人类活动主要是不合理的开垦加速植被破坏．人类活动叠加气候波动共同促使黄河流域生态环境的变迁．     

塔里木河流域下游绿洲演变对生态输水的响应

参考前人对绿洲的定义和分类方法,对塔里木河下游人工绿洲、天然绿洲进行提取,分析生态输水前后人工绿洲和天然绿洲的面积变化特征、转化过程、重心迁移情况以及扩张与退缩的空间变化。结果表明:1990—2015年,塔里木河下游绿洲总面积先下降、后上升,人工绿洲不断扩张,10 a平均增长量为46.78 km~2,天然绿洲面积不断缩减,在2000年后有所上升。生态输水前(1990—2000年),塔里木河下游来水量减少,导致大面积草地退化,天然绿洲面积减少;生态输水后(2000—2015年),部分未利用土地得到了利用,变成河渠、水库、湖泊、灌木林和高覆盖度草地,塔里木河下游生态有所恢复。下游绿洲重心先往西北,再往南方,最后又往东南方向迁移。绿洲主要向西北和东南方向扩张,1990—2000年的扩张区域主要集中于英苏上游区域;2000—2010年期间,台特玛湖地区绿洲面积增加明显;绿洲缩减区域分布广而零星。     

新疆霍尔果斯河流域植物区系研究

初步查明,霍尔果斯河流域有野生维管束植物85科463属1153种(含亚种、变种),其中蕨类植物8科11属23种,裸子植物3科3属10种,被子植物(双子叶植物63科376属910种,单子叶植物11科73属210种)74科449属1120种,并在该地区发现了珍稀物种半日花的新分布地和一种我国未曾纪录过的桦树。对该地区分布的种子植物区系进行分布区类型分析表明,首先是北温带分布及旧世界温带分布的比重最大,共有238属656种,占该地区种子植物总属、种数的60.10%、72.97%。其次为地中海区、西亚至中亚分布和中亚分布,共有113属169种,占该地区种子植物总属、种数的28.53%、18.80%。再次为温带亚洲分布的有14属21种,占该地区种子植物总属、种数的3.54%、2.34%。东亚分布有6属6种,占该地区种子植物总属、种数的1.51%、0.67%。东亚和北美洲间断分布的仅有2属2种,占该地区种子植物总属、种数的0.51%和0.22%。上述分析表明该地区植物区系与旧世界温带及地中海—西亚—中亚交流最多,其次与全热带及温带亚洲和东亚有一定的交流,而与东亚和北美洲及旧世界热带交流最少。     

明至清初青藏高原畜牧业经济初探

文章以大量的历史文献论述了以饲养马、牛、羊等牲畜为主的畜牧业生产在青藏高原诸游牧民族的生产生活中占据着主导地位.明代至清前期,青藏高原地区的农业经济虽然有所发展,但由于自然条件的特殊性,畜牧业生产依然在社会经济生活中占据着主导地位,肩负着促进当地社会经济发展的任务,明清政府在高原地区和接近高原地区设置的官营茶马贸易和官办马场,客观上对民间畜牧产业的发展起到了推动作用.以史为鉴,如何在生态环境脆弱的条件下推动高原地区经济的发展,以满足当地人民日常生活所需也是我们当代人需要思考的问题.