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41.
生态建设补偿的定量标准——以南水北调东线水源地保护区一期生态建设工程为例 总被引:8,自引:1,他引:8
生态补偿标准的确定是生态补偿机制建立的重点和难点.以南水北调东线水源地保护一期生态建设工程的补偿为例,探讨生态建设的补偿标准.从工程投资和机会成本的角度分析生态建设的总成本为1.46亿元/年,通过生态系统服务价值评价并结合专家咨询赋权,计算出生态建设工程成功实施后,建设区域所增加的生态服务效益为0.83亿元/年,外部区域所增加的生态服务效益为2.13亿元/年;综合生态建设成本和生态效益,提出了根据生态服务效益分担生态建设成本的补偿标准分析思路,并由此计算得到外部区域对建设区域的补偿标准为1.11亿元/年. 相似文献
42.
43.
Summary Vegetation dynamics after fire was studied in six communities in Bas-Languedoc (Southern France). 47 plots were observed by means of a permanent transect for ten years.In the first part, we describe floristic richness, species fugacity and the way by which, the terminal community (as defined by the last observation) appears. The dynamics of all these communities follows a simple and general model: floristic richness reaches its maximum during the first two years after a fire, then decreases and becomes stable. Fugacity follows a similar model, whereas the mergence of the terminal community is rapid: one year after fire 70% of the plots have already acquired 75% of the species of the terminal community. There is no succession (in the general sense of the word), but a progressive reappearance of the species belonging to the original community.In the second part, we study floristic similarities between our plots and corresponding associations as described in literature. It appears that after a fire the floristic diversity of the landscape remains high; while the communities rapidly reach a relative maturity.In the study area fire seems to be a rather superficial phenomenon; it does not lead to an important modification of the community dynamics, because probably the most frequent species in Bas-Languedoc developed adaptations to withstand fire. 相似文献
44.
基于条件价值法评估三亚海域生态系统多样性及物种多样性的维持服务价值 总被引:2,自引:0,他引:2
基于条件价值法(CVM)开展了三亚海域海洋保护区生态系统多样性和重要海洋物种多样性的维持服务价值评估。于2014年12月通过面对面调研的形式对三亚当地城镇居民进行问卷调查,建立了支付意愿(WTP)多元线性回归方程,再将此回归模型推广到海南全省城镇居民,从而评估了三亚海域海洋保护区生态系统多样性和重要海洋物种多样性的维持服务价值;同时也对CVM研究中的相关问题如问卷设计、偏差分析和CVM的可靠性与有效性等进行了验证和探讨。研究结果表明:(1)2014年三亚海域海洋保护区生态系统多样性及重要海洋物种多样性的维持服务总价值分别为3.734亿元和4.442亿元。(2)受教育程度和家庭人均年收入等社会经济信息变量对支付意愿具有显著的影响水平,符合经济学理论。(3) CVM作为陈述偏好性价值评估方法,评估结果受偏差的影响较大。为了尽可能减小偏差,需要从问卷的设计、调查员筛选培训、调查方式和被调查者等诸多方面严格把关。(4) CVM问卷支付数额的设计较好地界定了支付意愿的范围和分布形态,支付意愿具有较高的统计效率,CVM的可靠性得到较好的验证,显示了CVM评估法在估算生态系统服务非使用价值的有效性。鉴于居民的学历和收入在短时间内很难得到提升,建议相关海洋管理部门加强对三亚海域海洋保护区和海洋生物多样性的宣传教育,增强居民对三亚海洋保护区和海洋珍稀濒危生物的认知及保护意识。 相似文献
45.
Liu J Ma H He YL Xie B Xu YF Tang HY Li M Hao W Wang XD Zhang MY Ng CH Goding M Fraser J Herrman H Chiu HF Chan SS Chiu E Yu X 《World psychiatry》2011,10(3):210-216
This paper summarizes the history of the development of Chinese mental health system; the current situation in the mental health field that China has to face in its effort to reform the system, including mental health burden, workforce and resources, as well as structural issues; the process of national mental health service reform, including how it was included into the national public health program, how it began as a training program and then became a treatment and intervention program, its unique training and capacity building model, and its outcomes and impacts; the barriers and challenges of the reform process; future suggestions for policy; and Chinese experiences as response to the international advocacy for the development of mental health. 相似文献
46.
R. K. Gupta 《Plant Ecology》1978,37(2):111-118
Summary Effects of human influences on the vegetation of the Western Himalaya have been reviewed. Impacts of forest management practices, over-grazing, surface mining, defence and development operations, and road building activities, are severe in the region. This has created an alarming situation for soil and water conservation. Increased soil loss and runoff pose a threat to various reservoirs built for various uses and have increased hazards of erosion and floods in the Indus and Ganga basin regions.Nomenclature follows Hooker (1872–1897) and Gupta (1968). 相似文献
47.
Emiliano Ukmar Corrado Battisti Luca Luiselli Marco A. Bologna 《Biodiversity and Conservation》2007,16(12):3287-3300
Breeding bird communities in burnt and unburnt residual pinewoods were studied over 3 years by line-transect method, following
a catastrophic fire event in Castelfusano (Rome, Central Italy; July 2000). We applied bootstrap procedures to evaluate whether
the observed data were true or just produced by chance, and then examined the emerging patterns at three levels: community,
guild and species levels. At the community level, fire acted on breeding bird communities by altering especially the total
abundance patterns: the species abundance decreased in the burnt pinewood compared to the residual one, but other parameters
were not significantly affected by fire. As a consequence of fire, the destruction and structural simplification of the canopy
and shrubby component, as well as the increase of edge habitat and patchiness at landscape scale, induced a turnover in species
between pinewoods. Species turnover was higher at the burnt than at the residual pinewoods, during all the 3 years of study.
At the guild level, the forest species decreased strongly in terms of richness and abundance in the burnt pinewoods, contrary
to the edge and open habitat species which increased in terms of richness, abundance and evenness. Edge species showed the
highest turnover in burnt pinewood during the whole period of study. At species level, after an a priori subdivision (based
on bibliographic search) of the various species in two ecological guilds (forest versus edge species), it was found that an
a posteriori statistical analysis confirmed the expected trend, i.e. that the species which decreased significantly in burnt
pinewood were essentially the forest species, whereas the species which increased were essentially the edge/open habitat ones.
Overall, in order to investigate the effects of fire catastrophes on birds, the guild approach seems more exhaustive than
the taxonomic community approach, where intrinsic confounding trends are present. 相似文献
48.
We investigated the role of fire and other potential biotic and abiotic determinants for the occurrence of an obligate seeder
and active pyrophyte, Cistus salviifolius, a vulnerable species in the Swiss Red List. Populations of this species are threatened by the change of fire regime that
has occurred during the last ten years. Fires and burnt areas are today less frequent and it is not clear whether other factors
can compensate for such fire-free periods should this trend continue. We used a stratified random design to collect data on
the cover of three growth stages, i.e., juvenile, chamaephytic and nanophanerophytic (oldest), of C. salviifolius, on plant communities, and on environmental factors. A tree-based discriminant analysis showed that the time elapsed since
last fire was the best predictor of Cistus occurrence, but plants could survive on rocky and sunny sites if no fire had occurred for more than 32 years. Contrary to
our expectations, the number of fires and time elapsed since the last event was correlated with the oldest stages only, and
not with that of seedlings or juveniles. Rank correlations showed that bare soil was a good predictor of young stages, whereas
rocky outcrops and shallow soils were important for the chamaephytic stage. Our results confirm the role of disturbances and
competition-free habitats as determinants of the survival of this vulnerable pyrophyte during long periods without fires and
the existence of ontogenetic niche segregation of this species. In order to maintain viable C. salviifolius populations in the Alps, managers should undertake conservation actions according to the requirements of the different growth
stages of this species. 相似文献
49.
西安市城市化对景观格局及生态系统服务价值的影响 总被引:2,自引:0,他引:2
我国处于城市化高度发展阶段,截止2018年全国城市化率达到59.58%。城市的快速扩张,显著改变了区域景观格局,深刻影响城市生态系统的供给、调节、文化、支持等服务功能。近30年来,西安市城市用地扩张554.23 km2,基于西安市景观格局变化分析,利用同心缓冲区探讨城乡梯度内景观指数与生态系统服务价值的特征及其相互关系,揭示城市发展对城市生态系统的影响。结果表明,1980—2015年西安市各景观类型面积发生明显变化,耕地、草地面积逐渐减少,建设用地面积波动增加,主要来源于优势景观耕地的转化。景观破碎度最高的区域主要分布在距市中心10 km左右的城乡结合部,斑块密度、边缘密度、景观分割度最高,且随城市扩张,拐点距离逐渐增加。林地和耕地是提供生态系统服务的主要土地类型,西安地区总生态服务价值减少了9.56亿元,耕地减少最多(6.83亿元),沿城乡梯度,总生态系统服务价值均值呈现从市中心到农村递增的趋势,土壤保持的生态服务价值增长最快;沿时间梯度上,生态服务价值均值呈现逐年减少现象;从景观格局对生态服务价值影响分析得知,多样性指数与各类型生态系统服务价值之间存在显著的相... 相似文献
50.
Badosa E Ferre R Planas M Feliu L Besalú E Cabrefiga J Bardají E Montesinos E 《Peptides》2007,28(12):2276-2285
A 125-member library of synthetic linear undecapeptides was prepared based on a previously described peptide H-K1KLFKKILKF10L-NH2 (BP76) that inhibited in vitro growth of the plant pathogenic bacteria Erwinia amylovora, Xanthomonas axonopodis pv. vesicatoria, and Pseudomonas syringae pv. syringae at low micromolar concentrations. Peptides were designed using a combinatorial chemistry approach by incorporating amino acids possessing various degrees of hydrophobicity and hydrophilicity at positions 1 and 10 and by varying the N-terminus. Library screening for in vitro growth inhibition identified 27, 40 and 113 sequences with MIC values below 7.5 μM against E. amylovora, P. syringae and X. axonopodis, respectively. Cytotoxicity, bactericidal activity and stability towards protease degradation of the most active peptides were also determined. Seven peptides with a good balance between antibacterial and hemolytic activities were identified. Several analogues displayed a bactericidal effect and low susceptibility to protease degradation. The most promising peptides were tested in vivo by evaluating their preventive effect of inhibition of E. amylovora infection in detached apple and pear flowers. The peptide H-KKLFKKILKYL-NH2 (BP100) showed efficacies in flowers of 63–76% at 100 μM, being more potent than BP76 and only less effective than streptomycin, currently used for fire blight control. 相似文献