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1.
荒漠化程度的变化对南疆地区来说是生态系统退化的表现。应用NDVI数据,利用图像处理软件ENVI对南疆地区荒漠化程度进行分析,结果表明： 1952-1983年之间南疆地区荒漠化面积约增长11%,其中重度荒漠化面积约增14.21%左右,而中轻度荒漠化面积增7%~8%。1983-1993年荒漠化保持着基本稳定的状态。在21世纪初,即从2000年、2005年、2010年、2014年4期遥感数据解译分析结果来看, 2000年荒漠化总面积达到96.11×10 4 km 2,约占总面积的90.41%,其中严重荒漠化面积为72.93×10 4 km 2,重度荒漠化面积为15.76×10 4 km 2,中轻度荒漠化面积为7.42×10 4 km 2,到了2014年,荒漠化总面积达到95.31×10 4 km 2,比2000年下降1.24%,但严重中轻度荒漠化土地面积不断发生变化。通过分析发现,荒漠化程度变化主要是人类活动和自然因素共同作用所导致的。 相似文献
2.
以祁连山南麓中端野牛沟土壤为研究对象,研究了不同海拔下低温原油降解细菌群落的分布特征。结果显示：研究区域具有原油利用潜力的低温降解菌数量为0.3×10 5~1.4×10 5CFU ·g -1,随海拔的升高,菌群明显减少;同时通过16S rRNA基因序列分析共发现4个门、7个属、25种细菌,其中假单胞菌属（ Pseudomonas）和节杆菌属（ Arthrobacter）是优势属,并且位于海拔3597m处的菌株原油利用潜力均较高,而变形菌门的不动杆菌属（ Acinetobacter）利用原油生长的潜力最高。 相似文献
3.
冻融侵蚀是我国仅次于水蚀和风蚀的土壤侵蚀类型。青藏高原由于其海拔高、辐射强、气温低的特点,是我国冻融侵蚀较严重的区域。选择影响冻融侵蚀的5个主要因子：气温年较差、降水量、坡度、坡向、植被覆盖度进行定量研究,分析青藏高原冻融侵蚀敏感性强度及空间分布特征。结果表明：（1）青藏高原冻融侵蚀区面积为149.02×10 4 km 2,占青藏高原总面积的62.20%;冻融侵蚀敏感区的面积为56.80×10 4 km 2,中度及以上敏感区面积为27.39×10 4 km 2,占冻融侵蚀敏感区面积的48.22%;（2）冻融侵蚀敏感性空间分布差异明显,中度以上敏感区主要分布在青藏高原南部和东南部、喀喇昆仑山、祁连山、横断山区等地区。 相似文献
4.
基于辽河流域多目标地球化学调查取得的土壤表层和深层有机碳和全碳数据,探讨辽河流域土壤碳储量计算方法,分析辽河流域碳密度的分布特征.对辽河流域5.23×10 4 km 2土壤碳储量计算表明,深层（0~1.8 m）土壤碳储量为860.50×10 6 t,中层（0~1.0 m）为538.30×10 6 t,表层（0~0.2 m）为138.76×10 6 t;辽河流域土壤深层碳密度为16.45×10 3 t/km 2,中层为10.28×10 3 t/km 2,表层为2.65×10 3 t/km 2.分别根据土壤类型、地质单元、生态系统和土地利用类型的划分方式计算土壤的碳储量,为土壤碳循环研究与环境效应评价提供了科学依据. 相似文献
5.
水是绿洲存在和发展的核心, 干旱区绿洲稳定性与水密切相关. 根据2000-2009年资料, 采用蒸发系数法和定额法估算开都-孔雀河流域绿洲自然生态系统和社会经济系统综合需水量, 并对水资源约束条件下的绿洲稳定性进行初步探讨. 结果表明: 2000-2009年, 绿洲年均总需水量理论值约为54.80×10 8 m 3, 其中开都河绿洲总需水量约为20.55×10 8 m 3, 孔雀河绿洲总需水量约为21.90×10 8 m 3, 博斯腾湖区耗水量约为12.35×10 8 m 3, 与绿洲10 a平均供水量相比, 供需表现出极大地不平衡性. 水资源可承载绿洲面积(不含博斯腾湖)约为3139.66 km 2, 其中可承载灌溉地面积约为1395.41 km 2, 与绿洲10 a平均面积5 248 km 2相比, 差别较大, 绿洲处于不稳定状态, 现状绿洲面积应适当收缩. 最后, 对博斯腾湖最低生态水位进行讨论, 初步把大湖最低水位定为海拔1 045 m, 小湖最低生态水位定为海拔1 046.5 m. 相似文献
6.
2001年塔里木河流域四条源流出山口天然径流量计266.5×10 8m 3, 比多年平均值多40.70×10 8m 3, 增加1%.源流区在进入塔里木河干流前总耗水量为220.0×10 8m 3, 与多年平均值比较多43.4×10 8m 3, 增加24.6%, 而入塔里木河水量为46.4×10 8m 3, 比多年平均4.12×10 8m 3减少1.64×10 8m 3.塔里木河干流龙头站--阿拉尔站2001年年径流量为45.72×10 8m 3, 接近多年均值46.00×10 8m 3, 属平水年.干流上游区间耗水量24.77×10 8m 3, 占阿拉尔站年径流量的54.2%; 中游区间耗水量1.94×10 8m 3, 占阿拉尔站年径流量的41.4%; 下游区间耗水2.025×10 8m 3(纯塔里木河水), 仅占阿拉尔站年径流量的4.4%. 2001年从开都河-孔雀河的博斯腾湖和塔里木河向下游绿色走廊的应急输水于11月16日水流到台特玛湖, 从而结束了塔里木河下游近30 a干涸的历史, 使下游绿色走廊恶化环境开始恢复. 相似文献
7.
利用1986年（TM）和2001年（ETM）卫星遥感影像数据和RS-GIS集成技术,对松嫩平原盐渍化土地的现状、程度和发展趋势进行了量化分析.结果表明,这15年中,松嫩平原盐碱地面积增加了21.7112×10 4 hm 2,每年增加1.45×10 4 hm 2,年平均增长率为1.4%.其中轻度盐渍化土地增加8812 hm 2,年平均增长0.16%;中度盐渍化土地增加3.8306×10 4 hm 2,年平均增长0.64%;重度盐渍化土地面积增加了16.9994×10 4 hm 2,年平均增长了4.2%.气候变暖,降水减少,人为活动增强是盐渍化程度加重的主要驱动力. 相似文献
8.
基于中国自动气象站与CMORPH降水产品融合的0.1°×0.1°高分辨率逐时降水量网格数据集以及气象站点日降水的实测资料,对青藏高原面雨量的空间分布做了研究,并运用线性分析法对青藏高原季节面雨量和逐时面雨量的年际变化做了分析。结果表明：（1）0.1°×0.1°高分辨率格点降水数据能够准确地反映青藏高原面雨量的空间分布特征,东南缘的降雨量远大于西北部。格点数据与站点数据之间偏差率小于20%的站点占到站点总数（84个）的65.48%,相关系数大于0.9的站点有48个。（2）2008-2013年青藏高原总面雨量的年均值为133.42×10 10 m 3,夏季面雨量最大,占到全年面雨量的51.48%。四季面雨量均呈增长趋势,春、夏、秋、冬的线性倾向率分别为0.40×10 10 m 3·a -1、3.11×10 10 m 3·a -1、1.30×10 10 m 3·a -1和0.92×10 10 m 3·a -1。（3）面雨量峰值出现在19：00-20：00（北京时间,下同）,面雨量增多的时间出现在17：00-02：00。 相似文献
9.
内蒙古白云鄂博的氟碳钙铈矿,经电子衍射研究,观察到三种多型:4 H, P6 α=7.12Å c''=56.4Å;6 R, R3 α=7.12Å c''=84.6Å; 3 R, R3 α=7.12Å c'=42.3Å。其中4 H 为新多型。湖北竹山氟碳钙铈矿仅观察到一种多型6R。白云鄂博样品中发现3 R 与6 R 共晶格取向连生,以及3 R 型共格双晶。 相似文献
10.
依据铜陵太平－钟仓应急水源地水文地质条件构建水文地质概念模型.在此基础上,利用三维可视化软件GMS建立水源地地下水流数值模拟模型,并对模型进行了识别和验证.模型模拟期为一个应急供水周期180 d（2017－01～2017－06）,水源地开采层位为承压水.模拟结果表明：在采用均匀布井方案和限定开采井水位降深不超过承压含水层顶板的条件下,水源地允许开采量为11.94×10 4 m 3/d,达大型水源地规模（5×10 4 m 3/d<允许开采量<15×10 4 m 3/d）;水源地承压水在应急开采条件下,激发了长江侧渗补给量,袭夺量占水源地开采总量的27.82%.同时,通过模型模拟数据对傍河水源地地下水与地表水转换规律进行了初步探讨. 相似文献
11.
Migration is a global strategy for promoting economic growth and sustainable urbanization, specifically in developing countries. It is critical for governments to understand the determinants of migration decision for rural households so that proper migration measures can be taken. Different from previous studies that mainly focus on migration determinants without considering migration patterns, this paper divides migration patterns into three types—no migration, labor migration, and family migration, and examines the determinants for “no migration–migration” and “labor migration–family migration,” respectively. The binary logistic model is adopted to analyze the impacts of various migration factors in Chongqing city. Results show that: (1) per capita non-agricultural income plays the most significant positive role in driving “no migration–migration.” This is followed by the number of household labor force, whereas road accessibility is the key factor for inhibiting migration. (2) The key contributory factor for “labor migration–family migration” is per capita non-agricultural income. This is followed by the residential distance from towns, whereas the number of household labor force and the average age of labor force are restraining factors. The research results can effectively provide scientific reference for local governments to advance the transfer of the surplus rural labor force to promote sustainable urbanization. 相似文献
12.
The aim of this paper is to analyze the relationship between household expenditure and CO2 emissions among different income groups of urban and rural households in China. Having employed the 2007 Social Accounting Matrix of China, this study examines the direct and indirect CO2 emissions caused by household demand. The results show that within both urban and rural households, the higher the income level is, the higher the per capita emissions are; the CO2 emissions per unit expenditure due to savings and taxes are generally much larger than those from consumption of goods and services; and these emissions per unit consumption expenditures mainly come from indirect emissions. To deeply explore the relationships between consumption patterns and CO2 emissions, two scenarios are established to eliminate the differences in income level and consumption propensity among different groups step by step. Main results indicate that (1) the income gap is the primary cause of the significant differences in emission levels among each group; (2) the difference in consumption propensity is also a notable reason; and (3) the rural higher income groups spend a larger share of their income on those carbon-intensive goods (e.g., electricity, transportation, energy products), thus making their consumption patterns more carbon-intensive, while for the urban, the consumption patterns of lower income groups are more carbon-intensive. Finally, policy recommendations on the reduction of household emissions are also made. 相似文献
13.
The regional variation in the sales of a new product, a corrugated zink plate for roofing, is described and explained with the help of regression analysis covering a four year period following the product's introduction. Distance from the plant, share of rural population, income per capita, intensity of competition and a regional dummy explain 76–90 % of the regional variation in a year. As the product commands a practically uniform price and has identical availability irrespective of customer location, and as official marketing information is centralized and therefore also uniform, the distance and dummy variables should not appear in the regression equation. Their actual appearance and the positive sign of the competition-variable are explained by the spatial innovation effect. Its significance is evaluated and measures are suggested for its exploitation. 相似文献
14.
本文剖析了人均钢、水泥消费“S”形轨迹的三个重要转变点, 论述了人均消费量和消费强度变化规律的影响因素和内在机制, 阐述了产业部门钢消费强度的倒“U”形轨迹, 在分析国内外经济结构演变趋势的基础上, 提出我国第二产业占GDP比例已经达到顶点, 指出钢、水泥消费强度顶点大小及到来的时间。 相似文献
15.
通过美国100年来SO2排放趋势分析, 对比日本、英国的相关数据资料, 发现SO2的排放与能源消费、经济发展、环境政策以及环保技术进步密切相关: 经济结构的转变和能源结构的调整是SO2减排的关键因素, 环保政策和技术进步是SO2减排的主要驱动力。典型国家SO2排放强度曲线均呈倒“U”型, 符合环境库兹涅茨曲线。SO2排放的拐点美国在人均GDP15000美元, 日本和英国在人均GDP9000～10000美元; 三个国家人均SO2排放强度的拐点在人均GDP5000～7000美元, 目前中国已经越过人均SO2排放的顶点。在此基础上本文提出了中国进一步减排SO2的建议。 相似文献
16.
The regional inequalities in socio-economical characteristics such as income, population density, age composition, unemployment rate and the education level may bring about variation in waste generation, recycling and collection. Using environmental Kuznets curve, the factors affecting municipal solid waste disposal are examined. The results demonstrate that an inverted N-shaped curve executes on municipal solid waste disposal for all regions. As personal disposable income increases, per capita municipal solid waste disposed firstly declines, then grows at the second stage and finally decreases again. All the explanatory variables including economic factors, social characteristics and geographical barriers are found to influence municipal solid waste disposal significantly. Each person increase in population density leads to an increase in municipal solid waste disposed by approximately 1.17 ×10 ?4 kg/day. Each percent increase in age composition results in a decrease in municipal solid waste disposed by approximately 0.0224 kg/day; in the unemployment rate causes a decrease of 0.0901 kg/day and in the education level results in a decrease of 0.01556 kg/day. In general, municipal solid waste disposal starts to increase at the first turning point of personal disposable income NT$ 198,000 (about US$ 6,280) and to decrease at the second point of NT$ 389,000 (about US$ 12,350) for all regions (pooled data). The rural regions, however, cannot support the inverted N-shaped curve by the ‘reduced form’ while urban regions have a significant outcome. This result implies that income can only explain a portion of variation while other social and geographical factors contribute a lot to identify the variation in municipal solid waste disposal between urban and rural regions. 相似文献
17.
The aim of the paper is to examine wood as a source of fuel energy in rural South Africa and factors influencing its usage.
The analysis is based on household profiles and characteristics (e.g., gender, caste, population and income) in a livelihood
framework. Fuelwood consumption was estimated to be 692 kg/capita, and 4343 kg/user household per annum, valued at $311 per
household. Consumption was modelled in relation to informal and formal cash incomes, and population of children, female and
male adults. However, only the population of female adults could significantly influence consumption of fuelwood. This implied
that where there were more women in a household, consumption was likely to be high. This might be due to the majority of women
doing the cooking and heating in the household. Any change in the value of cash income of households had no significant impacts
on fuelwood consumed. Cash incomes might therefore not be strong determinants of the types of energy used by rural households.
The average quantity of wood consumed for fuel energy in summer was not significantly different from consumption in winter.
Some households perpetually used more wood than others. The study further showed that harvesting of wood for fuel energy is
not opportunistic, but requires reallocation of time for other livelihood activities in times of shortage. The fuelwood crisis
is not simple and not only about shortage of fuelwood and/or population growth but linked to household profiles and other
livelihood strategies and subsequently vulnerability of households. These would require thorough investigation and understanding
in relation to precise demand and supply data for fuelwood before the fuelwood problem can be sufficiently managed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
18.
Agriculture and natural resources have a mutual relationship with each other. The purpose of this study was to evaluate forward and backward relationship between natural resources and agricultural development. The relationship between the consumption of water and agricultural value added per capita income has been studied in order to obtain the forward relationship, and the relationship between carbon dioxide emissions and per capita income of the Iran’s agricultural sector has been assessed in order to obtain backward relationship. To test these relationships, the Kuznets theory is used. Therefore, Iran’s provinces information from 2001 to 2013 was used and models were estimated by using the panel data and spatial econometric. Results showed that there was an inverted U relationship between per capita income and water consumption and carbon dioxide emissions. Also, spatial estimation showed that both water consumption and carbon dioxide (CO 2) emissions in agricultural sector had a direct relationship with the value of these two variables in the neighboring areas. 相似文献
19.
地勘单位执行多年的经济指标考核体系一般由决算总收入、新增资本积累、净资产总额、应收账款与存货占经营收入比率、提取折旧额、提交煤炭资源量,人均年收入等七项指标组成。该指标体系经过多年运行,已经趋于成熟。但是该指标考核体系没有考虑到不同单位的综合经济实力和生产能力水平的差异,忽略了不同单位之间的主营业务性质和区域性差异,使考核结果公平性存在一定的缺陷。本文依据全面考核原则、科学考核原则、可操作性原则,探讨了如何改进经济指标考核体系,并提出了可供实施的企业经济效益综合指数考核指标体系。 相似文献
20.
利用乌鲁木齐市1990年8月6日、2001年7月11日和2013年7月4日三期热红外遥感数据,定量反演亮度温度,利用均值-标准差法对温度进行分级后评价城市热岛效应时间变化特征:1990、2001、2013年3个时段,乌鲁木齐市最大热岛强度分别为11.48℃,12.06℃和14.01℃;加权平均热岛强度分别为1.033℃,1.603℃,1.236℃;城市热岛比例指数分别为0.1054,0.3945和0.4328;乌鲁木齐市城市热岛效应在平均水平上呈现先增强、后减弱的趋势,最大热岛强度、热岛比例指数均增加,城市已初步形成区域内的"热岛",城市高温区温度将继续上升且面积存在扩展趋势.利用PSR模型构建指标体系对城市土地集约利用水平进行评价,在同时段内乌鲁木齐市城市土地集约利用水平和协调性均在提高.从评价结果出发,通过相关分析,得出基于土地集约利用的城市热岛效应影响因子包括:人口密度、建成区绿地覆盖率、地均国民生产总值、人均建设用地面积、人均道路铺装面积、地均固定资产投资,这些因子涵盖了经济、社会、环境三个方面. 相似文献
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