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1.
长三角地区1995-2007年生态资产时空变化   总被引:1,自引:0,他引:1  
徐昔保  陈爽  杨桂山 《生态学报》2012,32(24):7667-7675
结合遥感定量反演与经济评价法,利用1995年1 km的AVHRR-NDVI、2000年和2007年250m MODIS-NDVI等遥感数据,模拟与评估长三角1995-2007年生态资产时空变化.结果表明:长三角1995-2007年生态资产总量呈持续下降趋势,由1995年891.39亿元减少到2007年845.54亿元,减少5.14%;各地市生态资产总量总体呈下降趋势,但区域变化差异极其显著;长三角1995-2007年生态资产空间分布呈南高北低格局,空间变化呈南部和北部以轻度增长为主、中部以中度和严重退化为主的变化特征;土地利用变化是导致长三角生态资产减少及空间差异的主导因素,自上而下生态修复工程明显有助于增加区域生态资产.  相似文献   

2.
王南  张华 《生态科学》2011,30(4):406-410
基于2000年、2005年的土地利用数据,应用谢高地等人制定的中国陆地生态系统单位面积服务价值表,估算了阿鲁科尔沁旗土地利用格局变化引起的生态系统服务价值的改变。结果表明,从2000~2005年,阿鲁科尔沁旗土地利用结构变化幅度分别为,耕地增加13.39%,林地减少0.43%,草地减少2.29%,水域增加0.86%,湿地减少0.64%,城乡工矿居民用地增加12.02%,未利用土地减少0.25%。阿鲁科尔沁旗生态系统服务价值从2000年的12.87亿元减少到2005年的12.83亿元,净减少值为0.04亿元,减幅为0.31%。阿鲁科尔沁旗土地利用格局的变化,特别是耕地面积大幅度增加,草地面积减少是其生态服务系统价值下降主因。  相似文献   

3.
王鹤潭  巩贺  黄玫  张远东  孙玮  顾峰雪 《生态学报》2024,44(8):3213-3222
生态资产与人类福祉密切相关,开展生态资产评估并定量区分气候和人类活动对生态资产变化的相对贡献,对于评估区域生态文明建设成效、生态补偿、干部离任的自然资产审计等均具有重要意义。在单位面积价值当量因子方法的基础上,重新定义了标准生态服务价值当量因子,并构建了一个能够定量区分气候变化和土地利用变化对生态资产变化相对贡献的方法,以北京市房山区为例,分析了2000年至2019年房山区生态资产的变化,以及气候变化和土地利用变化对生态资产变化的相对贡献,结果表明:(1)房山区2019年生态资产总价值177.14亿元。森林、草地、农田和湿地的生态资产分别占生态资产总价值的82.33%、11.76%、5.25%和0.095%。(2)房山在2000-2019年期间,生态资产总价值增加了2.275亿元,气候变化使得房山区的生态资产总价值增加了2.689亿元,而土地利用变化使得生态资产总价值减少了0.414亿元。(3)房山区生态资产西高东低,其中霞云岭乡生态资产总价值最高;琉璃河镇的生态资产增加最多,而拱辰街道下降最显著。过去20年是房山区社会经济快速发展的时期,由于气候变化和生态保护与修复使得生态资产增加,抵消了由于建设用地扩张所带来的生态资产损失。  相似文献   

4.
生态资产就是生态系统服务价值, 通过生态系统的结构、过程和功能, 直接或间接为人类提供产品和服务。对生态资产价值, 以及与绿色发展之间的关系进行研究, 具有重要的现实意义。利用神农架林区2009—2018 年的土地利用数据, 并结合陆地生态系统单位面积生态服务价值当量表, 对2009—2018年神农架林区的生态资产价值总量进行分析研究。研究结果表明: (1)2009—2018 年, 神农架林区的生态资产价值呈下降趋势, 生态资产价值从2009 年的3480987.96 万元下降到2018 年的3465079.69 万元, 十年的时间神农架生态资产价值降低了15908.27 万元, 变化率为-0.46%。其中, 林地的生态资产价值占比最大, 贡献了97.66%的价值。(2)2009—2018 年, 神农架单项生态资产价值量均有所下降, 其中, 水文调节服务价值减少量最大, 减少了21.61%; 食物生产服务价值减少量最小, 为1.69%。生态资产的非使用价值是使用价值的2.7倍, 占比为73.10%。(3)运用BP神经网络模型, 预测出2023年神农架林区的绿色经济将占比达到75.17%, 生态资产价值与绿色发展显著相关, 相关系数为0.9287(P<0.05), 表明生态资产是绿色发展的根本和基础。保护神农架的生态资产, 从而实现生态资产的增值。  相似文献   

5.
北京市平谷区生态系统服务价值动态   总被引:11,自引:0,他引:11  
以北京市平谷区1995年和2004年土地利用/覆被数据为基础,利用中国不同陆地生态系统单位面积生态服务价值表对平谷区生态系统服务价值进行了动态分析.结果表明:平谷区生态系统服务价值由1995年的3.291×109元减少到2004年的3.044×109元,变化幅度为-7.50%;耕地和水域面积的减少是该区生态系统服务功能丧失的最主要原因;研究区水域生态系统单位面积生态服务价值量最大,森林生态系统对平谷区生态系统服务价值的贡献最大;该区生态系统服务价值动态变化凸显出研究区土地利用结构的不合理性,应加大研究区森林、农田和水域面积的比重,严格控制耕地向建设用地的转化.作为北京市的应急水源地和生态涵养区,今后须加强对平谷区生态和环境保护力度,促进其经济社会可持续发展,以保障首都水资源和生态的安全.  相似文献   

6.
参照谢高地等人修正的单位面积生态系统服务价值当量, 结合区域实际情况对研究区生态系统服务价值系数进行调整, 利用西咸新区2011-2020年土地利用规划数据, 采用生态系统服务价值计算公式和敏感性分析, 对研究区生态系统服务价值进行了估算及分析。结果表明: 2010年到2020年, 西咸新区生态系统服务总价值呈不断下降趋势, 生态系统服务价值总量减少了4.5224亿元, 其中耕地和园地的贡献最大, 分别占减少总量的41.5%和37.4%; 通过生态系统服务价值敏感性分析, 生态系统服务价值对生态系统服务价值系数是缺乏弹性的, 研究结果可信。西咸新区土地利用规划(2011-2020)实施中, 其区域生态系统服务总价值为经济目标GDP总量的1.16%-2.35%, 生态价值损失是巨大的, 从可持续发展的观点来看, 以单纯经济增长为目的的土地利用结构调整是不可取的。  相似文献   

7.
王军  严慎纯  余莉  张亚男 《生态学杂志》2014,25(4):1093-1099
土地整理作为土地利用变化的重要驱动因素,显著改变土地利用和景观格局,对区域生态系统功能及其服务价值产生影响.本文以吉林省大安市的土地整理项目为例,利用生态服务价值模型计算了村域、镇域和县域尺度下土地整理区的生态服务价值及其总量变化.结果表明: 以增加耕地为目标的土地整理项目易造成草地和湿地等具有较高生态服务价值的地类减少,导致不同尺度下土地整理区生态服务价值总量出现不同程度的下降.村域尺度下,整理后研究区总的生态服务价值为796.14万元,较整理前减少10.5%;镇域尺度下,整理后总的生态服务价值为84301.26万元,较整理前减少14.2%;县域尺度下,整理后总的生态服务价值为120585.76万元,较整理前减少33.1%.根据土地整理的生态服务价值评估,从提高生态功能入手,最后提出了土地整理的景观生态设计策略,以期为土地整理的持续发展提供决策依据.  相似文献   

8.
武汉城市圈生态服务价值时空演变分析及影响因素   总被引:5,自引:0,他引:5  
赵育恒  曾晨 《生态学报》2019,39(4):1426-1440
基于2005—2015年武汉城市圈土地利用变化过程,采用专家打分法对"中国生态系统单位面积生态服务价值当量表"进行修订,定量测算生态服务价值(ESV,Ecological Service Values)并比较不同功能与服务,分析武汉城市圈ESV的时空演变特征,以生态服务估算价值为基础构造了经济、景观与ESV三者之间的双对数空间回归计量模型;挖掘ESV时空变化的驱动因素,为区域生态系统管理提供科学基础。研究结果表明:2005—2015年间,武汉城市圈ESV逐年减少,2005年为176.175亿元,2010年为169.296亿元,2015年为153.717亿元;ESV在空间上呈现较为显著的地区空间差异,呈现以武汉市区为圆心的由外向内环层递减结构;从不同功能价值和单项服务来看,区域生态功能的调节服务文化服务供给服务,其中食物生产又是最为主要的单项服务功能,且在历年价值逐渐减少的同时保持相对稳定变化;驱动力影响机理的研究结果表明,生态服务价值总量与单项服务价值均与农村居民人均可支配收入和景观AI(Agglomeration Index)聚集度指数呈显著的负相关关系,与农业总产值显著正相关。社会经济的快速发展和区域景观格局的改变影响着生态系统的格局特征与生态过程,社会经济发展与景观演变一起共同影响与作用于生态服务功能并表征于货币经济核算价值的相对正负变化,为开展区域生态功能保护与补偿、促进区域性可持续发展提供了科学参考。  相似文献   

9.
生态系统服务价值变化在生态经济协调发展评价中的应用   总被引:7,自引:0,他引:7  
吴建寨  李波  张新时 《应用生态学报》2007,18(11):2554-2558
以区域土地利用/覆被数据为基础,分析了天山北坡生态系统服务价值的时空变化特征,并通过构建生态经济协调度(EEH)指数评价了区域生态经济发展水平及区域差异性.结果表明:天山北坡生态系统服务价值从1989年的319.93亿元增加到2000年的321.26亿元,增幅0.42%;区域整体生态经济发展处于低协调水平,东部地区协调度高于中、西部,其中8个市县的EEH值为正,生态经济发展处于协调水平,7个市县的EEH值为负,处于不协调水平.研究区生态经济发展已处于协调水平的边缘,须加强生态环境保护力度,促进生态经济协调发展,以最终实现区域的可持续发展.  相似文献   

10.
罗佳  黎蕾  姜芸  周小玲 《生态科学》2022,41(4):70-77
为量化湖南省森林资源发挥的生态效益,阐释不同区域森林生态系统服务功能的空间格局特征。基于湖南省第九次森林资源清查数据,采用分布式测算方法,对湖南省森林生态系统服务功能进行评估。结果表明2018年湖南省森林生态系统服务功能价值量为9815.64亿元·a-1。从9个评估指标来看,以生物多样性保护的价值量最大,达3298.92亿元·a-1,占全省森林生态系统价值量的33.61%;涵养水源价值量位居第二,为2570.29亿元·a-1,占总量的26.19%;森林康养价值量排第三,为1097.00亿元·a-1,占总量的11.18%;森林防护功能价值最低,仅有0.84亿元·a-1,只占总量的0.01%。从全省14个市(州)的森林生态系统服务功能总价值由高到低最大的是怀化市,为1475.36亿元·a-1,占全省的15.03%;永州市次之,为1172.24亿元·a-1,占全省的11.94%;郴州市第三,为1001.92亿元·a-1...  相似文献   

11.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

12.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.  相似文献   

13.
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.  相似文献   

14.
The unitary conductances and permeability sequences of the rat connexin40 (rCx40) gap junction channels to seven monovalent cations and anions were studied in rCx40-transfected neuroblastoma 2A (N2A) cell pairs using the dual whole cell recording technique. Chloride salt cation substitutions (115 mM principal salt) resulted in the following junctional maximal single channel current-voltage relationship slope conductances (γj in pS): CsCl (153), RbCl (148), KCl (142), NaCl (115), LiCl (86), TMACl (71), TEACl (63). Reversible block of the rCx40 channel was observed with TBA. Potassium anion salt γj are: Kglutamate (160), Kacetate (160), Kaspartate (158), KNO3 (157), KF (148), KCl (142), and KBr (132). Ion selectivity was verified by measuring reversal potentials for current in rCx40 gap junction channels with asymmetric salt solutions in the two electrodes and using the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The permeabilities relative to Li+ are: Cs+ (1.38), Rb+ (1.32), K+ (1.31), Na+ (1.16), TMA+ (0.53), TEA+ (0.45), TBA+ (0.03), Cl (0.19), glutamate (0.04), and NO3− (0.14), assuming that the monovalent anions permeate the channel by forming ion pairs with permeant monovalent cations within the pore thereby causing proportionate decreases in the channel conductance. This hypothesis can account for why the predicted increasing conductances with increasing ion mobilities in an essentially aqueous channel were not observed for anions in the rCx40 channel. The rCx40 effective channel radius is estimated to be 6.6 Å from a theoretical fit of the relationship of relative permeability and cation radius.  相似文献   

15.
A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.  相似文献   

16.
17.
The aim of this report has been to present results concerning analytical quality controls of Hg analysis of fish and sediment, analyses of Fe, Ca, total-P, K, pH, alkalinity, conductivity, colour and hardness (Ca + Mg) of lake water samples. Despite the fact that these are standard parameters in many regular water control programs, there are major differences in the reliability with which these parameters can be determined. The focus here is on an overall inter-laboratory comparison between the parameters. Six laboratories have been involved in the analysis. Selected results: pH gives the lowest (average) relative standard deviation (error), about 2 %; conductivity gives an error of about 5–7 %; alkalinity yields an average error of as much as 13–25 %, which is the largest among the parameters studied here; colour also gives a high error, 9–15 %; hardness gives a relative standard deviation of about 6–7 %. Of the other parameters (i. e., Hg, Fe, Ca and P), Hg gives the best reliability and Fe and P the lowest. To have knowledge of the reliability of the analytical data is of paramount importance in most control programs and research projects.  相似文献   

18.
We investigated the uptake of inorganic elements (Be, Na, Mg, K, Ca, Sc, Mn, Co, Zn, Se, Rb, Sr, Y, Zr, Ce, Pm, Gd, and Hf) and the effect of Ca on their uptake in carrots (Daucus carota cv. U.S. harumakigosun) by the radioactive multitracer technique. The experimental results suggested that Na, Mg, K, and Rb competed for the functional groups outside the cells in roots with Ca but not for the transporter-binding sites on the plasma membrrane of the root cortex cells. In contrast, Y, Ce, Pm, and Gd competed with Ca for the transporters on the plasma membrane. The selectivity, which was defined as the value obtained by dividing the concentration ratio of an elemental pair, K/Na, Rb/Na, Be/Sr, and Mg/Sr, in the presence of 0.2 and 2 ppm Ca by that of the corresponding elemental pair in the absence of Ca in the solution was estimated. The selectivity of K and Rb in roots was increased in the presence of Ca. The selectivity of Be in roots was not affected, whereas the selectivity of Mg was increased by Ca. These observations suggest that the presence of Ca in the uptake solution enhances the selectivity in the uptake of metabolically important elements against unwanted elements.  相似文献   

19.
The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.  相似文献   

20.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

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