11 resultados para industrialization

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LUCC是全球变化研究的核心主题之一,也是社会经济可持续发展的关键问题。改革开放后四川的社会经济发展非常快,在各种因素的驱动下,土地利用/覆盖发生了深刻变化。目前四川省缺乏基于实际调查数据的、全域性的、具有连续时间序列的LUCC和驱动力分析及土地可持续利用研究成果,这对我们从全局上把握全省土地利用现状、发展变化趋势,利用土地政策参与宏观调控,实现长期可持续发展目标,建设资源节约型、环境友好型社会极为不利。本研究针对这一问题,选取全川八大土地利用类型作为研究对象,研究了全省1996年到2006年的土地利用/覆盖格局和变化情况,分析了不同尺度的驱动因素,对全省农用地和建设用地的集约利用状况、潜力进行了分析评价,并提出相应的对策措施。 1.1996年-2006年10年来整个省域的土地利用/覆盖格局变化。 (1)1996年-2006年全省的土地利用/覆盖格局 1996年,全省是一个以农用地为主的土地利用/覆盖格局,林地和牧草地属于优势覆盖类型(合占69.17%),居民点及工矿用地和交通用地合占只有3%左右。 2000年的LUCC格局较为明显的特点是耕地所占比重下降0.4个百分点,水域和未利用土地所占比重有所下降,牧草地保持不变,其余地类所占比重有所上升。 与2000年相比,2004年林草地的优势格局进一步得到强化(合占比重达到70.23%)。耕地面积占幅员面积的比重下降0.83个百分点,略有下降的有未利用土地、水域和牧草地。值得关注的是在“退耕还林还草”的大背景下,牧草地占幅员面积的比重下降0.04个百分点。 到2006年,仍为林草地为主导优势的格局,二者合占上升0.15%。在城市化快速推进的背景下,居民点及工矿用地中的城市用地和建制镇用地占比重超过15%,农村居民点占比重降至76%。交通用地中农村道路占比重降至57.8%,公路用地占比重升至37.5%。五个地貌区的土地利用/覆盖格局与全省的变化基本一致。值得关注的是盆西平原区的交通用地上升幅度和盆地丘陵区的未利用土地的开发利用力度明显大于其它地貌区。 (2)1996-2006年10年间土地利用/覆盖格局的变化 1996-2000年4年间,耕地、水域和未利用地三个地类下降,年均减少0.75、0.19和0.32个百分点。其中耕地年均减少49229.0公顷,约一半流向林地,13.77%流向园地,约20%流向建设用地。另外5个地类面积增长,增长绝对量最大的是林地,年均增长40063.7公顷,交通用地增幅最大,4年年均增长达1.95%。 2001-2004年是西部大开发逐步推进、“退耕还林还草”项目全面展开和土地整理深入实施的关键期,LUCC更为深刻。耕地、未利用地、水域和牧草地四个地类面积下降,其余地类按增长幅度依次是园地、交通用地、居民点及工矿用地和林地。耕地加速下降,年均降幅达到1.59%,其减少去向主要是林地(占66.75%)和园地(占19.84%),其增加来源主要是未利用地、园地和水域。交通用地的增幅最大,为3.96%,其增加主要来源于耕地、未利用土地和林地,分别占49.96%、16.63%和13.09%。居民点及工矿用地增长幅度为3.12%。 从1996年到2006年的10年间,耕地、未利用地、水域和牧草地下降幅度分别为10.36%、3.61%、1.34%和0.26%。园地增幅达23.61%。绝对面积增长最大的则是林地,达630733.3公顷。交通用地和居民点及工矿用地增幅也较大,分别为15.00%和9.31%。 10年间年均总变化量为310326.6公顷,2000年-2004年之间变化最大(为356865.8公顷),高于平均变化量,而1996-2000年间和2004-2006年间都小于平均变化量。 (3)10年间不同地貌区的LUCC变化 盆西平原区的特点是园地大幅上升达77%,居民点及工矿用地和交通用地也大幅上升,耕地、未利用地下降幅度大,该区耕地、水域、未利用地的减少强度和园地、居民点及工矿用地、交通用地的上升强度均居五区第一;盆地丘陵区的特点是牧草地下降幅度大,为-36.89%,交通用地、园地和林地上升幅度较大,该区耕地减少、未利用地减少、林地增加、居民点及工矿用地和交通用地增加的变化强度均居五区相应地类增减的第二位;盆周山地区的特点是耕地减少较多,交通用地和园地增长较大,该区林地变化强度居各区第一位,牧草地和水域变化强度居各区第二位,耕地、居民点及工矿用地和未利用地居各区第三位;川西南山地区的特点是园地、耕地、交通用地和居民点及工矿用地变化幅度大,另外四个地类变化较小。该区减少的牧草地占全省牧草地减少的97.91%,变化强度居各个地貌区的第一位,园地相对变化强度居五区的第二位;川西北高山高原区的特点是耕地大幅下降、园地大幅上升,交通用地升幅也较大,其余地类变化不大。值得注意的是,该区牧草地和水域面积增加,与全省该地类的变化相反。其余地类的相对变化强度均是五个地貌区中最小的。 用变化强度分值考量变化强度,盆西平原区的变化强度最大,盆地丘陵区和盆周山地区的变化强度相当,川西北高山高原区的变化强度则要小得多。 (4)1996年及2006年全省土地利用/覆盖格局的景观生态学分析 全省是以自然景观占优势(占约70%)、农业景观为补充、建设用地景观居于从属地位的土地利用景观格局。景观多样性和均匀度不高。到2006年,全省总的景观格局并无大的改变。总体情况是随着时间的推移和人类活动的加强,区内景观优势度上升、多样性和均匀度变小。但斑块数减少,斑块面积和斑块孔隙度有所增大。斑块的形状指数和分维数均有所下降,表明受人为干扰有加剧的趋势。反映景观格局结构的破碎度指数有轻微下降。景观指数的变化表明全省土地利用有缓慢集中、规模聚集的趋势。 (5)三大生态建设工程对土地利用/覆盖变化的影响 1996-2006年间LUCC与三大生态建设工程实施的耦合分析,发现退耕工程对耕地、林地、牧草地等地类覆盖变化的影响最大,天保工程次之,长防工程最小。 2.四川省LUCC驱动力分析 (1)总体分析: 从整体上分析,人为因素对区域整体LUCC的影响从1996年的63.32%增加到2006年的66.99%,变得日益强烈。同时人为因素影响强度表现出明显的区域差异,地势平缓、经济区位条件好的区域其人为影响强度明显较高。 政策体制转变下的经济高速增长、快速的城市化、工业化过程和生态建设是四川省LUCC宏观尺度的驱动因素。区域的LUCC主要受到了由内向外(从城市到乡村)和由外向内(从山顶向平地)两种作用力的共同推动。局部尺度上,如距离交通线、水利线、中心城市的远近,地形凸起、大型独立项目落址、重污染项目的阻隔等,甚至一些乡规民俗等因素也会成为LUCC的驱动影响因素。在较小的尺度上,人类个体行为选择对LUCC的影响也是存在的。   根据驱动因子的特性作者将其划分为驱变、阻变、良性、惰性因子等类型。 (2)分地貌区的驱动因子分析 各地貌区都存在城市化、工业化、生态工程实施、自然灾害等驱动因子,但主次不一。对于盆西平原和盆地丘陵区,城市化、工业化是前两位的因子,而对另外三个地貌区,生态工程实施和产业结构调整则成为第第一、二位的驱动因子。 (3)分地类的驱动因子分析(以坡耕地为例) 分坡度的耕地变化分析发现,耕地减少主要集中在2°以下的平地、15°-25°和25°以上三个坡度级,是其它坡度级耕地减幅的三倍左右。这表明耕地减少受城市化进程和“退耕还林还草”工程驱动影响尤为巨大。 3.土地利用格局优化、集约利用评价和可持续利用及对策研究 (1)土地利用格局优化的战略选择及调整预测 土地利用格局调整的战略是农业生产用地、建设用地和生态及其他用地占幅员的比重分别稳定在13%、7%和80%左右,重点是三大类别内部二级和三级地类的合理调整。 (2)全省土地集约利用评价 全省农用地利用集约度为0.46,总体上集约度不高,处于较适度利用阶段。建设用地利用集约度为0.38,处于较适度利用阶段。集约利用提升空间较大。 农用地的潜力主要在于加强土地保育、完善利用制度、提高单产。城市建设用地的包括存量潜力、强度潜力、结构潜力,空间很大。农村居民点整理潜力可以逐步挖掘。 (3)新增建设用地集约利用的统筹安排 据测算,到2020年,四川省城市建设用地需求量在463850-492360hm2之间,城镇各业新增建设用地规模为361276.79hm2,占用耕地200565.94 hm2。2004-2020年间四川省农村居民点整理潜力33.86万hm2。农村居民点建设用地需求量为70.57万公顷。 (4)土地集约利用措施与坡耕地可持续利用战略 提出了土地集约利用的措施。在对坡耕地生态系统结构与功能分析的基础上,提出坡耕地可持续利用战略与生态恢复战略,并从技术和政策层面提出了坡耕地合理利用和生态退耕的措施和建议。 LUCC is one of the key questions of global change and sustainable development of society. After the opening and reform of China, the society and economy of Sichuan Province developed very fast ,the land-use/cover changed very strong droved by many factors .But nowadays we have no constant spatial-temporal study and driving force analysis about the whole province based on investigation. And it is lack of land sustainable utilization study based on correlative study. So we choose all the land resource in Sichuan, combine RS and GIS and field investigation, and take statistic-mathematic means and system analysis, to study the LUCC patterns and different scale driving force of different physiognomy regions, land cover types and periods; to analyze the current situation and potential of land resource intensive utilization, and gave out corresponding measurements. We found that forest and grassland are the dominant cover types of Sichuan provincial land –use/cover pattern, and becoming more and more stronger from 1996 to 2006,the natural landscape is the metric and occupy 70%,the diversity and evenness index are not high; the totally change quantity from 2000 to 2004 is the biggest; cultivated land especially steep cultivated land ,garden plot, forestry land ,settlement and industry land and traffic land changed relative stronger; among five physiognomy regions ,the changing intensity of PEN XI PING YUAN QU is the biggest, CHUAN XI BEI GAO SHAN GAO QU is smallest; under the background of policy system changing, the fast developing of economy, fast urbanization and industrialization and ecology construction are the macro-scale driving force of Sichuan provincial LUCC; to compare the impacts of “TUI GENG GONG CHENG” on LUCC especially to cultivated land ,forestry land and grassland is strongest, “TIAN BAO GONG CHENG ” is stronger,“ HANG FANG GONG CHENG” is smallest; the intensive utilization level of farmland and construction land of whole province is relative moderation, there is huge potential to excavate and fulfill the increasing demand of construction land;we must take synthetic measurements to accelerate the sustainable utilization of land resource, including administrative, economical ,technological and ecological policies.

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为满足 2 1世纪中国对粮食的需求 ,提出“发展东部 ,提高中部 ,开发西部”的粮食生产战略布局 ,就是在东部平原区发展产业化粮食生产 ,使之成为中国优质商品粮食主要生产基地 ;在中部高原区要大力治理水土流失 ,提高粮食生产的环境质量 ,从而提高粮食产量水平 ;在西部高寒及荒漠区要充分开发光能、土、水资源优势 ,进一步开发高寒农业与绿洲农业的粮食生产潜力

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作为黄土高原半农半牧区重要经济支柱的畜牧业 ,要确保其稳定增长 ,需在提高粮食单产、保障食物安全的前提下 ,保持及改善生态环境 ,通过畜牧业发展农村经济 ,增加农民收入 ,改变农村贫困落后状态。同时畜牧业可持续发展需要经济系统、社会系统、技术系统的共同支撑 ,优化协调畜牧业生产中的外部条件和环境 ,配套解决和优化畜牧业系统内部矛盾是畜牧业可持续发展的必经之路

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The interactions among industrial development, land use/cover change (LUCC), and environmental effects in Changshu in the eastern coastal China were analyzed using high-resolution Landsat TM data in 1990, 1995, 2000, and 2006, socio-economic data and water environmental quality monitoring data from research institutes and governmental departments. Three phases of industrial development in Changshu were examined (i.e., the three periods of 1990 to 1995, 1995 to 2000, and 2000 to 2006). Besides industrial development and rapid urbanization, land use/cover in Changshu had changed drastically from 1990 to 2006. This change was characterized by major replacements of farmland by urban and rural settlements, artificial ponds, forested and constructed land. Industrialization, urbanization, agricultural structure adjustment, and rural housing construction were the major socio-economic driving forces of LUCC in Changshu. In addition, the annual value of ecosystem services in Changshu decreased slightly during 1990-2000, but increased significantly during 2000-2006. Nevertheless, the local environmental quality in Changshu, especially in rural areas, has not yet been improved significantly. Thus, this paper suggests an increased attention to fully realize the role of land supply in adjustment of environment-friendly industrial structure and urban-rural spatial restructuring, and translating the land management and environmental protection policies into an optimized industrial distribution and land-use pattern.

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Rapid urbanization and industrialization in southern Jiangsu Province have consumed a huge amount of arable land. Through comparative analysis of land cover maps derived from TM images in 1990, 2000 and 2006, we identified the trend of arable land loss. It is found that most arable land is lost to urbanization and rural settlements development. Urban settlements, rural settlements, and industrial park-mine-transport land increased, respectively, by 87 997 ha (174.65%), 81 041 ha (104.52%), and 12 692 ha (397.99%) from 1990 to 2006. Most of the source (e.g., change from) land covers are rice paddy fields and dryland. These two covers contributed to newly urbanized areas by 37.12% and 73.52% during 1990-2000, and 46.39% and 38.86% during 2000-2006. However, the loss of arable land is weakly correlated with ecological service value, per capita net income of farmers, but positively with grain yield for some counties. Most areas in the study site have a low arable land depletion rate and a high potential for sustainable development. More attention should be directed at those counties that have a high depletion rate but a low potential for sustainable development. Rural settlements should be controlled and rationalized through legislative measures to achieve harmonious development between urban and rural areas, and sustainable development for rural areas with a minimal impact on the ecoenvironment. (C) 2009 Elsevier Ltd. All rights reserved.

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Since reform and opening up, how much contribution has China's implementation of new agricultural policy made to agricultural output? This paper is trying to establish an agricultural policy output econometric model for doing a quantitative analysis of China's new agricultural policy. The results show that China's agricultural policies on agricultural output have an average contribution rate of about 7% since 1978, which is consistent with the OECD's basic forecast. There are obvious temporal and spatial differences. Generally speaking, we can divide the contribution of agricultural policy into three periods, which are the start-up phase from 1978 to 1991 (14 years), the stationary phase from 1992 to 2002 (11 years) and the rising phase from 2003 to 2008 (6 years). In space, the contribution of agricultural policy underwent a process from the all-low in the start-up phase, the gradual increase in the stationary phase to the all-high in the rising phase. Northern and western regions are more sensitive to policies. There are three major factors that can affect the contribution of regional agricultural policies, which are the process of national industrialization strategy, terrain and the level of local finance.

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In this work, studies were carried out on the extraction properties of Mn(II) and MnO4- in sulfuric acid medium using Cyanex 923. Effects of different variables on the extraction of Mn(II) and MnO4-, such as the concentrations of acid, the extractant, and the temperature, were investigated. Results indicated that Mn(II) was extracted weakly by Cyanex 923; however, MnO4- could be strongly extracted into the organic phase. The extraction mechanism of MnO4- was proposed, and the influence of MnO4- on the extraction of cerium was identified when KMnO4 as oxidizer added into the bastnasite sulfuric acid leaching liquor. As MnO4- was easier to be extracted into the organic phase than Ce(IV) and then lost its ability for oxidization, a new device was designed to realize sufficient oxidization of cerium from III to IV, and which has been applied to industrialization.

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该文通过大量实验,确定了制备单糖、寡糖及低聚糖的最佳生产工艺,并对几种制备方法做了比较研究.该文采用氧化降解和微波降解等不同技术对甲壳低聚糖的制备工艺进行了研究.H<,2>O<,2>作为氧化剂,在酸性条件下,采用4因素3水平进行正交实验,得到了制备分子量2000以下的寡糖的最佳条件.微波降解制备低聚糖目前尚未见报道,经过该实验证明此方法可降低能耗,减小污染,节省时间和原料,是一个具有产业化前景和市场潜力的好方法.通过以不同的壳聚糖为原料,探讨了在微波场作用下纯溶剂及盐效应对分子量变化的影响,最终产物的分子量均在1×10<'5>~10×10<'5>之间.根据IR光谱,壳聚糖降解前后主要峰的位置都无变化,只是随壳聚糖相对分子质量的降低各峰峰强有所变化,证明了壳聚糖氧化降解及微波降解制备寡糖、低聚糖是以开裂壳聚糖的β-1.4糖苷键来进行.该项研究对更好的开发利用甲壳质资源,促进中国海洋生物制品的发展具有十分重要的意义.

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比较了连续生产过程与离散生产过程的不同特点,提出了适合连续生产过程CIMS的体系结构.并从参考模型,开发工具和集成平台等三个方面探讨了实现CIMS如何走工程化和产业化道路的问题。