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1.
西南岩溶区生态环境可持续发展的生态足迹分析——以广西为例 总被引：3，自引：0，他引：3
生态足迹是一种度量可持续发展程度的方法,能定量判断一个区域生态环境的发展是否处于生态承载能力的范围内.以西南岩溶地广西为例,采用生态足迹的理论和方法对2004年广西区域生态足迹状况进行了测算和实证分析,并与2003年进行了比较.结果表明:广西人均生态足迹由2003年的1.1378 hm2上升到2004年的1.2239 hm2;人均生态承载力由2003年的0.5753 hm2下降到2004年的0.5736 hm2,广西经济社会活动对生态环境的需求强度已经超过了生态承载力的供给;人均生态赤字由2003年的0.5625 hm2增长到2004年的0.6503 hm2,处于不可持续的发展状态.必须采取相应措施,促使广西生态环境发展向良性和可持续方向转化. 相似文献
2.
评价自然灾害前, 区域的生态足迹可了解当地自然生态系统的开发和利用状态, 结合主体功能分区的方法可为灾后重建提供更契合实际的政策建议. 基于合理灾后重建的理念, 从可持续发展的角度分析了2011年甘肃东乡"3.2"滑坡灾害发生前(2010年)县域生态足迹和生态承载力情况, 并根据海拔和坡度对区域进行功能分区. 结果表明: 草地人均生态足迹为0.94 hm2, 生态承载供给为0.022 hm2, 赤字0.92 hm2 , 草地土地类型存在严重的生态赤字, 直接导致整个县域人均生态赤字0.97 hm2. 这表明东乡县人民的消费需求超过了自然系统的再生能力, 人类的生产、 生活强度超过了生态系统的承载力, 区域生态系统处于人类的过度开发利用和压力之下. 由于进出口贸易不大, 因此, 东乡县主要是通过消耗自然资本存量来弥补生态承载力的不足. 考虑到东乡县的实际情况, 通过主体功能分区把该区域分为农业发展区、 生态恢复区以及二、 三产业发展区. 其中, 农业发展区面积为838.24 km2; 生态恢复区面积为701.98 km2, 包括退耕还林的面积264.84 km2; 二、 三产业发展区面积105.57 km2. 最后根据生态足迹和功能分区的计算结果, 结合实际情况提出了未来可持续发展的政策建议. 相似文献
3.
基于能值-生态足迹模型的湖北省生态安全评价 总被引：1，自引：0，他引：1
基于能值分析法改进的生态足迹模型,对1997-2014年湖北省生态经济系统长时间序列可持续发展趋势和生态安全状况进行了定量分析。结果表明：研究期内湖北省多年平均能值密度为1.286×1015 sej·hm-2,人均能值生态承载力从1.18 hm2下降到1.10 hm2,人均能值生态足迹由4.50 hm2增加到8.72 hm2。从1998年起湖北省人均生态足迹逐年扩大,以年均6.2%的速度快速增长,一直处于生态赤字状态,且赤字增大趋势明显;生态压力指数从3.82增长到7.95,生态安全形势严峻。湖北省生态环境系统不足以维持自身经济社会快速发展,其中城市建设发展和重工业的能耗压力大以及进出口总额剧增是造成区域生态赤字的主要原因。 相似文献
4.
将旅游生态足迹引入区域旅游可持续发展评价,阐述旅游生态足迹的概念,构建旅游生态足迹模型,用于衡量旅游可持续发展能力。以陕西省作为研究对象,对旅游生态足迹模型在大尺度区域旅游业可持续发展定量测度中的运用进行实证研究,计算其1991年至2008年的旅游生态足迹。结果表明:陕西省出现了不同程度的旅游生态赤字和生态压力,平均存在0.033 1 hm2/人的旅游生态赤字,其旅游业处于不可持续发展状态。提出未来实现旅游业可持续发展应做到加强旅游文化内涵挖掘、大力发展生态旅游及特色旅游、充分发挥政府职能、完善法律法规等。 相似文献
5.
The urban fringe, which can be seen as a special form of regional ecosystem with a spatial transition from urban to rural
areas, has strong heterogeneity and is a typical ecologically sensitive area. The expansion of cities and the landscape effect
of the changes have attracted wide attention. The primary aim of this study is to obtain an understanding of the spatial patterns
of landscape conversion and the corresponding environmental sustainability. With the help of GIS and Fragstats software, the
changes of landscape patterns before and after town planning were compared in An-Ding town of Beijing, of which the sustainability
was also revealed based on the ecological footprint using social and economic statistic data. The results showed that the
landscape pattern changed greatly during its conversion from several villages to a small town and the landscape fragmentation
increased due to road construction. Meanwhile, human disturbance increased with the constructed land extension. For the gap
between the ecological footprint and the biological capacity, An-Ding town ran an ecological deficit at that period, which
means it was unsustainable. However, the environmental sustainability decreased after planning due to the degraded green land
and forest. The results suggested that ecological management should be strengthened during the town planning period. 相似文献
6.
基于GRNN模型的岩溶地区城市水生态足迹分析与预测 总被引：5，自引：0，他引：5
为揭示岩溶地区城市生态足迹的驱动因子与机制,评估和预测水资源可持续利用程度,根据岩溶地区水文地质特征及其与水生态足迹的相关性,分析了贵阳市2002-2014年水生态足迹的变化特征,并利用GRNN模型对其进行了时间序列预测。结果表明,贵阳市水生态足迹由2002年的12.79万hm2上升至2014年的15.74万hm2,整体呈波动上升趋势,其中,水量生态足迹变化特征主要由工业用水量决定,水质生态足迹变化特征主要由氨氮排放量决定。水生态承载力波动变化明显,且小于水生态足迹需水量,导致水资源可持续利用系数介于0.31~0.63之间。对贵阳市2015-2019年水生态足迹进行GRNN预测,表明水生态足迹呈现先升后降得趋势,水生态承载力变幅在4.315~8.038万hm2之间,但水生态足迹与承载力的缺口大,水资源可持续利用系数偏低。因此,在水生态承载力有限的贵阳市,降低水生态足迹才是实现水资源可持续利用的关键。 相似文献
7.
Wenguang Yang Hongbo Zheng Ke Wang Xin Xie Guocheng Chen Xi Mei 《Frontiers of Earth Science》2008,2(2):170-176
Sediments with high sedimentation rate at site MD05-2905 in the Northeastern slope of the South China Sea provide unique materials
for a high-resolution study on the paleoenvironment. Based on precise dating of AMS 14C, grain size analysis of terrigenous debris at core MD05-2905 was conducted after organic matter, biological carbonate and
biogenic opal were removed. The results show that 15.5–63.5 μm coarse grain size ingredients may indicate East Asian winter
monsoon changes and that 2–9 μm fine grain size ingredients may be used as a proxy of evolution of the East Asian summer monsoon.
The results of grain size analysis, which suggest East Asian monsoon intensity, reveal that a winter monsoon dominated the
glacial regime and a summer monsoon dominated the Holocene regime. It was also shown that the summer monsoon increased gradually,
experienced several abrupt changes and reached a culmination in the early Holocene (11200–8500 a B.P.) since 36 ka. Controlled
by precession periodicity, it may be related with the amount of solar radiation at the highest stage, which needs further
study.
__________
Translated from Advances in Earth Science, 2007, 22(10): 1012–1018 [译自: 地球科学进展] 相似文献
8.
A diel biogeochemical study was performed to assess the influence that periods of elevated biological activity have on the biogeochemical cycling of macronutrients and redox-sensitive elements in a natural estuarine environment. High-resolution data (15 min sampling) illustrates periodic extreme variations in dissolved oxygen (DO) in the shallow waters of Azevedo Pond, Elkhom Slough, California. During periods of low tidal flushing, DO values can range from highly oxic (>560 μM O2: >250% saturation) during sunny days to suboxic conditions (<5 μM) at night. Nutrient cycling and redox-sensitive trace element biogeochemistry were evaluated in response to the extreme daily DO fluctuations. A diel sampling study was conducted over a 26-h period, where O2 concentrations ranged from 346 μM to sustained non-detectable levels in the night hours. In concert with the DO fluctuations, diel phosphate cycling was on the order of 4 μM in response to tidal flushing events and biological assimilation and regeneration. The IO3 −/I− redox couple quickly responded to suboxic conditions in the water column by a marked increase in I− concentrations and corresponding depletion of IO3 −. The extreme fluctuations of the p∈ in the water column resulted in diel dissolved Mn2+ variations of nearly 5 μM, with observed dissolved Mn removal rates on the order of 1 μM h−1. The elevated biogeochemical cycling of oxygen, nitrogen, phosphorus, iodine, manganese, and iron found in this shallow estuarine environment suggest that tidal restrictions and anthropogenic nutrient enrichments can amplify diel variations and potentially hinder the functional and ecological stability of these systems. These data suggest that accurate chemical monitoring of the health of an estuarine ecosystem must account for the diel variability inherent in these highly productive environments. 相似文献
9.
岩溶地区旅游生态安全评价及趋势分析——以广西为例 总被引：1，自引：1，他引：0
岩溶地区拥有丰富的旅游资源,但是生态环境相对脆弱,根据岩溶地区旅游发展的特点,以"压力-状态-响应"（PSR）模型为基础,同时从生态安全的概念出发,涵盖生态风险、生态健康和生态足迹指标,建立了岩溶地区旅游生态安全评价指标体系。调整的主要指标包括:土地压力指标、旅游经济密度、年平均气温和年平均降雨量指标、旅游空间密度、游客密度指数、旅游收入指标等。采用综合指数法和熵权法,分别引入2012年和2007年两年的数据,对广西岩溶地区旅游生态安全的现状、发展趋势及变化趋势的内在原因进行了分析。实证结果表明:（1）从现状评价看,2007、2012年广西岩溶地区旅游生态安全水平总体较低,处于安全级别的城市主要位于广西中部区域,其他城市则处于不安全级别;（2）从影响指标看,经济状态和旅游生态状态对当地的旅游生态安全影响较大;（3）从变化趋势看,广西岩溶地区旅游生态安全状态逐渐好转,广西中部地区保持安全状态,紧邻广西中部地区的地市处于持续危险区域,但综合指数呈上升趋势;梧州和贵港两个位于广西东部的城市同样处于持续危险区域,但是旅游生态安全综合指数呈小幅下降趋势;（4）旅游生态安全状态和趋势与岩溶分布没有显著的相关关系。 相似文献
10.
The changes in the water chemistry of rivers can reflect influence of anthropogenic activities on the water environment to
some extent. To understand the relationship between the spatial distribution of the eco-environment of the watershed and the
characteristics of water chemistry and geochemistry of rivers, firstly, the digital Wujiang watershed was built, and then
the sub-watersheds were delineated, taking the sample points as sub-watershed outlets based on GIS. Secondly, using the function
of spatial analyst of GIS, the statistical features of eco-environment (such as lithology and land use/cover) of each sub-watershed
were calculated according to their respective classification. Finally, the correlation between the spatial distribution of
lithology of the sub-watersheds and their corresponding 87Sr/86Sr ratio of river water, the correlation between NO3
−/HCO3
−, Cl−/HCO3
−, SO4
2−/HCO3
− and anthropogenic activities, respectively, and the correlation between the fraction of green vegetation of the sub-watershed
and their corresponding flux of TDS (total dissolved solids) were analyzed quantitatively. The results justify that the 87Sr/86Sr ratio of river water is highly dependent on the lithologic feature of the watershed and indicate that anthropogenic activities
are one of the main sources of NO3
− and SO4
2− of river waters. The output of TDS is highly dependent on the percentage of vegetation cover of the watershed. 相似文献
11.
12.
Tidal flats play a tremendous role for solving the problem of land use because of the crisis of population increments. Many coastal countries have carried out reclamation projects near seas in various degrees for a long time. China currently has about 2.13?million?hm2 of tidal flats that are mainly scattered in the delta plains and coastal regions near medium- to large-sized rivers. The tidal flats in China are reserves featuring dynamic growth and a capacity for continuous expansion; the tidal flat area undergoes an annual increase of over 20,000?hm2. In recent years, countries around the world have paid much attention to the marine ecological environment and have taken measures to restrict the scale and range of sea reclamation. Although widespread reclamation of tidal flats in China has taken place, such activities have also brought some negative effect: (1) water overdraft, seawater intrusion, (2) tidal gates and channel silting, (3) environment pollution, unbalanced ecosystem, and (4) loss of wetlands and threats to the survival of species. This paper examines the mechanisms associated with tidal flat dynamic growth, and points out that artificial siltation can greatly increase the growth speed of tidal flats, and the actual measured annual siltation thickness may reach 0.5?C2.7?m. At present, this paper proposes a theory relating to the ecological exploitation of this ecosystem as follows: (1) the principle of adjustment to local conditions; (2) the principle of three-dimensional distribution; (3) the principle of ecological balance; (4) the principle of green and environmental protection. In practical terms, this dynamic growth may play a significant role in mitigating conflicts relating to land use demands in coastal areas. 相似文献
13.
Hydrogeological and hydrochemical framework of regional aquifer system in Kali-Ganga sub-basin, India 总被引：5，自引：0，他引：5
The central Ganga Basin is one of the major groundwater reservoirs in India. The Kali-Ganga sub-basin is a micro watershed
of the central Ganga Basin, containing a number of productive aquifers. A detailed hydrogeological investigation was carried
out, which reveals the occurrence of a single-tier aquifer system down to 163 m bgl (metres below ground level), but at places
it is interleaved with clay layers; thus imparting it a two-to three-tier aquifer system. These aquifers are unconfined to
confined in disposition. The transmissivity, storage coefficient and hydraulic conductivity are determined as 2178 m2/day, 1.12×10–5 and 120 m/day, respectively. The groundwater of the basin is fresh, of an alkali-bicarbonate type and is suitable for irrigation
and domestic use. However, in certain areas, extensive agricultural activities, and domestic and industrial effluents have
caused some deterioration of groundwater quality. This study contains data of where the concentration of Fe, Pb, Cd, Cr and
Ni are higher than the permissible limits, which may be hazardous to public health.
Received: 2 March 2000 · Accepted: 3 July 2000 相似文献
14.
On August 13, 2004, Hurricane Charley came ashore in the Charlotte Harbor watershed. Surface winds at the time of landfall
were estimated at 130 knots. The track of the hurricane roughly followed the floodplain of the Peace River, causing massive
defoliation and mortality of native vegetation and planted citrus groves, as well as substantial damage to human habitation
and various infrastructure elements. Eight days after landfall, a water quality monitoring effort documented hypoxic (<2 mg
I−1) to nearly anaerobic (<0.5 mg I−1) dissolved oxygen (DO) values throughout the vast majority of the Peace River's c. 6,000 km2 watershed. Low DO values appeared to be related to high values of both dissolved organic matter and suspended materials.
Hypoxic conditions in Charlotte Harbor itself, occurred within 2 wk of landfall. Approximately 3 wk after the landfall of
Hurricane Charley, Hurricane Frances struck the east coast of Florida, causing further wind damage and bringing substantial
amounts of rain to the Charlotte Harbor watershed. Three weeks later still, Hurricane Jeanne caused similar damage to the
same area. In response to the combined effects of these three hurricanes, DO values in the Peace River did not recover to
pre-hurricane levels until approximately 2–3 mo later. The spatial and temporal pattern of DO fluctuations appeared to be
related to the proximity of sampling locations to the path of the eyewall of the first of the three hurricanes. Within the
Harbor itself, the duration of hypoxic conditions was less than that recorded within the Peace River, perhaps reflecting greater
dilution of oxygen-poor waters from the watershed with less-affected water from the Gulf of Mexico. 相似文献
15.
青海湖流域生态补偿空间选择与补偿标准研究 总被引：3，自引：1，他引：2
生态补偿是环境保护对策措施中的一种创新途径.以青海湖流域为研究区域, 以碳蓄积量作为主要生态系统服务目标, 结合人文调查数据和自然模拟结果, 分别采用福利成本法和最小数据方法对研究区生态补偿中的空间选择和补偿标准确定进行了分析.结果表明: 环青海湖四个县的生态补偿效率成本比分别是海晏县0.5353、 刚察县0.5398、 天峻县0.5549、 共和县0.4353.在生态补偿资金有限的情况下, 生态补偿的优先顺序依次是天峻、 刚察、 海晏, 最后是共和.若海晏县全部低盖度草地退牧则需付费328.5元·hm-2·a-1, 可年新增碳固定量1.7×107 kg; 若刚察县全部低盖度草地退牧则需付费250.5元·hm-2·a-1, 可年新增碳固定量5.25×107kg; 若天峻县全部低盖度草地退牧则需付费181.5元·hm-2·a-1, 可年新增碳固定量18.52×107kg; 若共和县全部低盖度草地退牧则需付费478.5元·hm-2·a-1, 可年新增碳固定量2.86×107kg. 相似文献
16.
流域生态系统评价体系是评价研究流域是否健康的基本依据,其评价结果为流域生态系统保护措施和政策制定提供基础。在介绍流域生态系统健康状态的前提下,总结了国内外流域生态系统评价理论和评价指标的发展历史及现状,整合出目前较为流行的评价体系,并着重阐述了五类实用模型,分别为:水基系统评价模型、改进物元分析、生物完整性指数法、压力-状态-响应模型(PSR)及景观格局分析法。针对不同的流域环境选择合适的评价体系是准确评价流域生态系统健康状况的根本。总结得到综合指标评价体系,主要包括物理、生物、社会环境、生态功能及社会功能等五种指标,在明确指标后按评价流程对流域进行系统评价。对现存的问题进行了分析与展望。 相似文献
17.
海岸带是中国社会经济发展的前沿地带,人口密度最大、城镇化程度最高,在中国海洋强国战略中发挥重要的支撑作用,同时也是中国资源环境压力最大的区域。本文在全面分析近20年来中国海岸带地质资源环境调查成果的基础上,系统梳理了海岸带地区地质资源环境优势和存在的地质环境问题。中国海岸带地质资源环境优势突出,为绿色发展提供了良好条件,重要地质资源环境优势包括:1.2×10~4km~2滩涂后备土地资源可适度开发,以缓解海岸带建设用地紧张局面;2.8×10~4km~2绿色富硒土地和4.1×10~5km~2绿色渔场,适宜发展绿色特色农业和建设海洋牧场;浅层地温能和地热水年可开采量折合标准煤4.2×10~8t,对改善能源结构、减少大气污染有重要作用;5.8×10~4km~2滨海湿地和134处国家级和世界级地质遗迹资源,为海岸带生态文明建设提供了条件;90%的陆域适宜城镇和重大工程规划建设,地下空间开发条件较好,为海岸带地质安全提供了保障。存在的主要环境问题包括:海岸带局部存在活动断裂、地面沉降、地面塌陷、海岸侵蚀淤积、风暴潮等重大地质问题,对部分城市与重要基础设施形成威胁,局部地区水、土污染及海水入侵严重,需要高度重视。建议加大海岸带多学科综合地质调查,构建多要素、多圈层、多维度地质模型,查明自然灾害发生的规律和原因,减轻对人民生命财产造成的损失。 相似文献
18.
生态足迹分析方法是近年发展起来的一种用生产性土地面积来定量衡量人类对自然资源利用程度和可持续发展能力的新方法. 旅游业对生态环境的影响程度和可持续发展能力可以用旅游生态足迹定量反映出来. 以生态足迹理论为基础,以湖南娄底市为实证对象,对2005-2012年旅游生态足迹、旅游生态承载力变化趋势进行分析. 结果表明：2005-2012年娄底市旅游生态足迹和旅游生态承载力都逐年增加,但二者增幅差异大,2010年是旅游生态盈余转为生态赤字的拐点,当前娄底市旅游发展以生态环境的退化为代价,是一种不可持续的旅游发展状态. 从旅游消费结构看,娄底市旅游生态足迹的7项分足迹中,以交通和餐饮生态足迹相对较大,而住宿、游览、娱乐、购物和废弃物排放产生的生态足迹相对较小. 实现娄底市旅游可持续发展对策：发展低碳旅游,提高资源利用率,合理控制旅游生态足迹的需求;保护旅游生态环境,提高旅游生态承载力;加强旅游生态安全控制,建立生态补偿机制. 相似文献
19.
西南岩溶石山地区生态承载力的演变及动力机制——以贵州省为例 总被引：4，自引：4，他引：0
生态可持续发展是区域永续发展的重要条件,西南岩溶石山地区生态承载力供给状况及其支撑社会经济发展的水平是地区发展关注的重要问题。文章以贵州为例,采用基于生态足迹理论下的生态承载力计算方法,利用贵州1978-2013年各类型土地利用面积数据计算并分析了贵州生态承载力的演变特征和动力机制。结果表明:贵州多年平均的生态承载力总量为2 690.560万hm2;经历了1978-1986年的低值期（年均2 440.734万hm2）、 1987-1989年的提高过渡期,到1990-2013年达到较高水平（多年平均值2 899.654万hm2）;但贵州的人均生态承载力总体上呈降低趋势（多年平均值为0.796 hm2）;各类土地提供的承载力中,耕地的生态承载力最大,占65.9%,其次是林地占25.4%,建筑用地占7.2%,牧草地占1.4%,水域约占0.13%;1978-1985年,贵州生态有盈余,但逐年减少,从1986年开始出现亏损,并呈逐年增大趋势;贵州生态承载力的演变主要受土地利用方式、土地生产能力和人口数量的驱动。 相似文献
20.
Groundwater exploitation and recharge rate estimation of a quaternary sand aquifer in Dar-es-Salaam area,Tanzania 总被引：1，自引：1，他引：0
Ibrahimu Chikira Mjemah Marc Van Camp Kristine Martens Kristine Walraevens 《Environmental Earth Sciences》2011,63(3):559-569
Dar-es-Salaam City gets water supply from surface water and groundwater. The groundwater is used to supplement surface water
supply and has increasingly become a major source of water supply in the city. The study area comprises three major parts:
the central coastal plain with quaternary fluvial–deltaic sediments, the deltaic Mio-Pliocene clay-bound sands and gravels
in the northwest and southeast and the Lower Miocene fluviatile sandstones of Pugu Hills in the west of the study area. The
main objective of this study was to quantify the integrated water balance. The major source of renewable groundwater in the
aquifer is rainfall. Hence, the average recharge of 256.2 mm/year (for the year 2006) to the aquifer was estimated using the
balance method of Thornthwaite and Mather, which is equal to 99.4 hm3/year for the whole alluvial aquifer. This value was balanced with total groundwater abstraction of 8.59 hm3/year, baseflow to rivers of 75.7 hm3/year and discharge into the sea (15.11 hm3/year). 相似文献