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1.
This paper uses the ecological footprint model to make comparison of the eco-efficiency of arable land ecological footprint in different years in Hubei Province, and makes comparison of that in Hubei and some countries. The results indicate that, since 1965, the eco-efficiency of arable land ecological footprint in Hubei has been improved year by year. However, the efficiency of arable land ecological footprint, compared with some other areas in the world, is much lower. In 1965, average eco-efficiency of world arable land ecological footprint is 3 421 US dollar/hm^2 while that of Hubei Province is 134 US dollar/hm^2, about 1/26 of the world's average level. The eco-efficiency of arable land ecological footprint for 2003 in Hubei Province, however, has become about 1/9 of the world's average level for the same year. Finally the author puts forward the ways to raise the eco-efficiency of arable land ecological footprint.  相似文献   

2.
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.  相似文献   

3.
By constructing evaluation indicator system of sustainable land use of Tibet from three aspects of ecological environment, economic development, resources and social advancement, this article studies the following contents respectively in two dimensions of time and space: the changes of sustainable land use of Tibet in recent 20 years and spatial characteristics of sustainable land use of Tibet in 2002. The following conclusions can be drawn from evaluation results .① With regard to com- prehensive evaluation value of sustainable land use, the trend of Tibet sustainable land use evaluation values from 1983 to 2002 are very close to the comprehensive evaluation values of ecological environment, which is up trend; ② sustainable utilization degree of land use in eastern region of Tibet is much higher than that of western region. ③ the sustainable land use evaluation value of Nyingtri County is the highest, and the counties with relatively higher land sustainable use values include Lhasa, Lhoka, Chamdo. While Nakchu, Ngari, Shigatse counties have the relatively lower evaluation values; ④ By analyzing each evaluation indicator's weight on sustainable land use, it can be concluded that the key limiting factors of sustainable Tibet land resource utilization are land desertification, grassland degradation and low economic level.  相似文献   

4.
许恒龙  Song  Weibo  Zhu  Mingzhuang  Wang  Mei  Ma  Honggang  Xu  Xiaozhong 《高技术通讯(英文版)》2005,11(4):432-436
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.  相似文献   

5.
This paper presents a study on species diversity and its ecological service function in the plateau area in western Sichuan. The results show that species diversity in the plantations on the cutover land has a tendency to increase and that its ecological service function is to be improved with stand age growing. The species diversity in forest communities is also gradually increased on different succession stage till reaching a climax level. But the species diversity in the climax community is slightly decreased before it reaches a relatively constant status. Ecological service function of diversity is gradually strengthened with the progress of succession. In addition, species diversity in a stand in a similar site and at a same age differs among forest types. Species diversity index within a coniferous and broad-leaved mixed forest is larger than that within a coniferous forest. Meanwhile, species diversity enriches as the tree density increases.  相似文献   

6.
In this paper, systematic design and act of eco-security is discussed as a focal point of conflict and unrest. The situation of ecosystem, the schematic framework of eco-security design, the main acts of ecosystem improvement, major difficulties and challenges have also been analyzed. The purpose of this study was to formulate the systematic framework of eco-security maintenance, to highlight systematic idea or philosophy of ecological rehabilitation and eco-security. A three-dimensional schematic model is applied to design the security of ecosystem. It was concluded that: 1) maintaining ecological security requires far better and sophisticated resource management skill and ecological improvement measures, and is also a continuing and multifaceted task. It cannot be permanently accomplished by a single action and program; 2) at present, technical system and policy and law system dimensions of ecological security are not enough even in short; 3) development of ecological industries is beneficial to local economic development and ecosystem protection.  相似文献   

7.
Fission track (FT) ages of apatite and zircon from four granite batholiths from Lhasa and Shannan areas are measured.The FT ages of apatite range from 3.2±8.3 Ma, corresponding to the uplift rates of 0.12±0.20 mm·a~(-1) during this period. The upliftheight is 580m, showing that there is not large-scale rapid uplifting in southern Tibet from 3.2 to 8.3 Ma. The zircon FT ages of Lhasabatholith are 25.9±1.7 and 32.7±2.8 Ma, yielding an uplift rate of 0.08 mm·a~(-1) between 26 and 33 Ma. Combining this work withother studies, it is suggested that the average uplift rate in southern Tibet is low from the time of collision between India and Asian conti-nents to ~3Ma. The uplift of Tibetan Plateau seems to have finished in multi-stage processes with varied rates.  相似文献   

8.
Glaciers are extensively developed in the southwest of Tibet and the moraines are widely distributed with large depth. Large-scale debris flows are often reported which blocked rivers and formed dams. In this paper, seven large debris flows in four valleys are discussed, among which five dams developed. 13 sets of experiments have been conducted in laboratory to simulate the formation and failure of the dam. Finally, a model of dam failure is proposed and a formula is established to calculate the flood discharge: Q=kbnnk/TB^-/LG^0.1,where bk is the outlet width of the dam at the original water level, hk the erosive depth, T the time from overflow to final state of failure, the average width of lake; L the length of the lake, and G the total potential energy of the water in the lake.  相似文献   

9.
Based on the model of grassland climate ecological productivity, the process of grassland degradation and its restoration mechanism in northern Tibetan Plateau were discussed by the model of food-chain in which the environmental and human factors were corrected. The results of case study in Nierong County showed that: ① the climate trend of becoming warmer, more droughts and gales were conflicted with the restoration of grassland degradation, even under level of perfect management the climate ecological productivity was declined from 89. 3 kg/m^2 of 1983 to 71.8 kg/m^2 of 2003; ② from 1983 to 2003, the population increased fast, while the variation of livestock on hand was little, and the cost of its maintaining is rapid grassland degradation; ③ on the present condition of overgrazing, the livestock on hand can be maintained on the level of theoretical carrying capacity in 2033 by applying the mechanism of food-chain in grassland ecological system controlled with expected coefficients, so that to realize the policy of determining the quantity of livestock according to grass growth.  相似文献   

10.
Nearly 200000 animal skeletons are unearthed in the Unit T0202 from Zhongba Site of Zhongxian County.According to the analysis of 129165 specimens,these skeletons may be classified into 5 kinds, namely,Mammalia,Osteichthys,Aves,Amphibian and Reptilia,which belong to 13 orders,28 families and 42 genera.In this paper,based on archeological dating and AMS 14 C data,through statistically analyzing the unearthed skeletons and studying the change of the smallest individual numbers,these research results detected the following:1)In almost all the time of 2370―200 BC,in Zhongba region, some animals distributed widely,such as Muntiacus sp,Elaphodus cephalophus and Muntiacus sp. inhabiting in glade and grassland,Scrofa sp.and Canis familiaris raised by the ancient people,rodentia rabbit and Rattus rattus,which suggested that a fairly good ecological environment of forest and grassland was preserved at that period and the predecessors began to raise domestic animals from 1750 to 1000 BC,which has lasted until today.2)Rhinoceros only lived during 2000―1750 BC,1000― 700 BC and 700―500 BC,which indicates that the ecological environment of grassland and wetland might be better in these phases.3)Macaca sp.and Ursus arctos appeared only after 1750―1000 BC, which may show that the forest condition is better for animals to live during 1750―200 BC.4)The smallest individual numbers of Bublus sp.,bos sp.and otters emerged during about 2370―1750 BC, which perhaps infers that water area during the early period was wider than that of the late period.5) Since skeletons of rhinoceros are discovered in strata of Zhongba Site during 2000―1750 BC and 1000―500 BC,according to the climate and ecology environment which rhinoceros live in now,the average annual temperature and precipitation during 2000―1750 BC and 1000―500 BC are supposed to be probably higher than that of today.Although Zhu Kezhen considered that the first low temperature period in the past 5000 years of China was between 1100 BC and 850 BC,massive pollen  相似文献   

11.
本文以经典生态足迹模型为基础,对吐鲁番地区2007—2015年的生态足迹情况进行动态测算,并利用主成分分析和多元线性回归方法,建立了人均生态足迹驱动模型。结果表明,吐鲁番生态足迹出现拐点,由2007年的3.53hm2/cap上升到2013年的7.0hm2/cap后又降到2015年的6.16hm2/cap;吐鲁番人均生态足迹动态变化是人口、经济、技术等多方面因素共同作用的结果,经济发展引起的消费水平提升是人均生态足迹动态变化的主要驱动力。  相似文献   

12.
 为选择区域生态足迹的预测模型结构的合理形式,提出把一般回归模型(GRA)作为区域生态足迹预测模型结构,用加速遗传算法(AGA)进行高精度GRA统一建模的新方案,从而建立了基于AGA的区域生态足迹一般回归模型(AGA-GRA)。AGA-GRA的实证结果说明:在2005-2020年期间,安徽省人均生态足迹将由1.724 6升至2.148 6 hm2,平均年增长率为1.48%;人均生态承载力由0.415 8降至0.338 8 hm2,平均年减少率为1.36%;人均生态赤字由1.323 7升至1.876 0 hm2,平均年增长率为2.35%;万元GDP生态足迹由1.836 7降至0.395 9 hm2/万元,平均年减少率为9.73%。安徽省的人均生态赤字仍在不断加剧,说明现有的社会经济发展模式是不可持续的。AGA-GRA克服了普通时间序列分析和回归分析模型中预先确定简单函数曲线则预测误差大而预先确定复杂曲线则模型求解困难之间的矛盾,提高了模型拟合和预测能力。  相似文献   

13.
沈阳市交通生态足迹的实证研究   总被引:5,自引:0,他引:5  
介绍了城市交通生态足迹的模型和方法,并以沈阳市为例对城市交通生态足迹、生态效率做了定量计算与分析.结果表明:沈阳市2004年交通生态足迹为35×104hm2,其中,能源消费间接用地占99%,而道路和场站直接用地仅占1%;从生态足迹构成看,小轿车和出租车生态足迹较高,分别为18.5×104hm2,5.61×104hm2,占交通总足迹的比例分别为53%,16%;从城市交通生态效率看,公共汽车最高,为3.06×104人次.hm-2,小轿车最低,为0.12×104人次.hm-2;从城市交通生态足迹强度看,小轿车最高,为8.38×10-4hm2.人次-1,公共汽车最低,为0.33×10-4hm2.人次-...  相似文献   

14.
应用生态足迹指标对沈阳市高校可持续发展的研究   总被引:7,自引:3,他引:7  
根据生态足迹成分法的基本原理和计算模型,计算、分析了东北大学等沈阳市九所高校2003年的校园生态足迹和生态效率.研究结果表明:大学校园生态足迹中,主要成分为能源消耗、食品消费和垃圾排放;培养一名学生一年的生态资源占用量约为0.4~1.4 hm2的生态生产性土地;九所高校的生态效率为0.7~2.5人.h m-2.应用该结果从节能、杜绝食品浪费、垃圾处理以及如何开展有效的生态教育方面,为沈阳市高校如何实现自身的可持续发展并通过生态教育为全社会的可持续发展服务,提出了具体规划措施和建议.  相似文献   

15.
张云兰 《广西科学》2023,30(5):961-971
开展长时间序列的广西农业生态经济系统安全评价、安全影响因素和安全预警研究,可为系统安全调控、农业可持续发展和乡村振兴提供决策参考。本研究采用生态足迹模型核算2000-2021年广西农业生态经济系统人均生态足迹和人均生态承载力,通过资源利用效率指数、生态盈亏、生态压力指数评价系统安全状况,利用偏最小二乘(PLS)模型分析系统安全的影响因素,基于灰色GM(1,1)模型开展系统安全预警,并将预警结果与云南、贵州进行比较。结果表明,2000-2021年广西农业生态经济系统人均生态足迹增长90.30%,其中林地增长最快,耕地占比最大;人均生态承载力下降0.67%;系统资源利用效率提高72.97%,但2011年以来增幅较小;系统生态赤字从-0.395 hm2/人不断加剧到-1.292 hm2/人,生态压力指数从1.66升高到3.18,系统从中度不安全状态逐渐转变为重度不安全状态,并开始进入极度不安全状态;人均耕地面积和耕垦指数对系统安全具有正向影响;2022-2033年系统安全由重警转为巨警,警情等级高于贵州和云南。因此,要提高耕地保护力度,促进农业转型...  相似文献   

16.
四川南充市生态占用初步研究   总被引:2,自引:0,他引:2  
利用南充市 2 0 0 2年统计数据 ,计算和分析南充市 3个城区 :顺庆、高坪、嘉陵的生态占用和生态承载力 ,比较判断南充市生态消费是否处于生态承载力的范围内。结果显示 ,南充市三区 2 0 0 2年的人均生态占用为1.10 16 hm2 · a- 1 ,人均生态承载力为 0 .174 2 hm2 · a- 1 。南充市是生态赤字区 ,人均生态赤字达到了 0 .92 74hm2· a- 1。  相似文献   

17.
1990-2004年安徽省生态足迹动态分析   总被引:4,自引:0,他引:4  
文章采用可变世界单产法计算了1990—2004年安徽省域尺度上的生态足迹,表明研究期内人均生态足迹和人均生态赤字分别由1990年的1.0121 hm2、0.5014 hm2增加到2004年的1.6523 hm2和1.2397 hm2,人均生态承载力和万元GDP生态需求则分别由0.5108 hm2、8.5601 hm2减少到0.4125 hm2和2.1270 hm2。说明了近年来安徽省人口对自然资源的消费量逐年增加,超出自然生态系统的承载能力,生态足迹与生态承载力之间的矛盾加剧,社会经济的发展模式不可持续。  相似文献   

18.
采用基于能值改进的生态足迹模型,考察了广东省1978—2006年人均消费足迹和人均产出承载力变化过程,发现都是增长的过程,且产出承载力的增长速度高于消费足迹增长。分别对生物资源账户、能源账户、工业账户、劳务和贸易账户进行分析,研究消费足迹和产出承载力的结构特征以及变化趋势。消费总足迹的增长中,非生物资源消费足迹占据了主要地位,而产品产出承载力的增长也主要得益于第二产业的发展。30年改革开放的制度变化,广泛的区域分工以及产品贸易与流通,人力资本的不断提升都是广东省承载力不断提升的重要原因。  相似文献   

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