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1.
吴旗县退耕还林生态效益价值评估   总被引:44,自引:0,他引:44  
生态效益的评价和核算对评价林业生态工程的建设效果至关重要。综合运用专家咨询、理论分析法和频度分析3种方法。建立了吴旗县退耕还林生态效益评价指标体系,使用市场价值法、影子工程法、机会成本法和替代法等方法,对该县退耕还林6年来的生态效益进行了价值核算。结果表明:吴旗县退耕还林工程具有巨大的生态效益,核算后的总生态价值约为24.8亿元,其中拦蓄保护水资源价值为6.4亿元,保护土地资源退化价值为6亿元,净化空气价值为5.3亿元,改善小气候价值0.3亿元,保护农田价值为0.02亿元.增加生物多样性价值为6.7亿元。研究结果可为黄土区退耕还林工程建设效益评价提供参考。  相似文献   

2.
我国平原林业净化空气与固碳释氧价值核算   总被引:3,自引:0,他引:3  
运用机会成本法、影子价格法对2001和2005年我国平原林业净化空气和固碳释氧价值进行核算。结果表明:1)2001和2005年我国平原林业净化空气和固碳释氧的总价值分别为14 609.23亿和18 739.27亿元。2005年,东北区、华北区、华东区、中南区、西南区和西北区平原林业的净化空气价值分别为2 574.96亿、2 975.93亿、5 285.94亿、3 172.19亿、316.43亿和1 238.33亿元,固碳释氧价值分别为906.30亿、426.35亿、838.49亿、665.25亿、52.04亿和287.06亿元;2)平原林业净化空气和固碳释氧总价值排序为华东区>中南区>东北区>华北区>西北区>西南区。平原林业在净化空气和固碳释氧方面的生态服务功能价值相当可观,应该大力推进平原地区林业生态工程的建设步伐和管理水平,对改善我国平原地区空气质量,增加林业碳汇功能具有重要意义。  相似文献   

3.
重庆四面山森林生态系统服务功能价值的初步评估   总被引:29,自引:0,他引:29  
采用机会成本法、市场价格替代法等手段对重庆四面山地区典型亚热带常绿阔叶林生态系统 的涵养水源、保持土壤、净化空气、固定CO2、休闲游憩等生态系统功能进行了初步估 算.最后得出该地区森林生态系统的涵养水源价值为1.035亿元、保持土壤价值为0.279 7亿元、固定CO2价值为0.837 9亿元、净化空气价值为0.687 0亿元、休闲游憩价值为1.90 0 4亿元.该地区森林生态系统服务功能的总价值为4.74亿元 .  相似文献   

4.
通过收集长江三峡库区22个区(县)30个退耕还林样地的调查数据,参考LY/T 1721—2008《森林生态系统服务评估规范》,对其中6种主要退耕还林模式涵养水源与保育土壤效益及其价值进行评估。结果表明:1)三峡库区6种主要退耕模式总调节水量(即涵养水源量)达到11.679 1亿t/a;调节水量的价值为68.37亿元/a,净化水质价值约为24.42亿元/a,涵养水源总价值约为92.79亿元/a;2)保育土壤总价值为0.903 6亿元/a,其中马尾松林、落叶阔叶林、竹林、板栗林、柑橘林和茶林保育土壤的价值分别为1 531万、2 251万、1 031万、2 815万、1 157万和251万元/a;3)三峡库区不同退耕模式取得的涵养水源效益和保育土壤效益都存在很大差别,因此,对三峡库区退耕还林工程生态效益不能只从总体上进行评价,还应该考虑不同退耕模式的生态效益,以便更好地评价和指导三峡库区退耕还林工程的实施;4)评价一种退耕模式的好坏,还要综合考虑多种生态效益。  相似文献   

5.
白龟山水库是河南省平顶山市的主要供水水源。基于生态服务价值原理和当地实际,对该水库湿地生态系统的生态价值进行了评估。结果表明:该水库直接的物质生产价值为17.757亿元人民币,水库消落带土壤和植被固碳释氧总价值为1.424亿元人民币,在提供野生生物栖息地、维护生物多样性等服务功能方面的年生态效益为0.221亿元人民币,调蓄洪水功能价值为6.177亿元人民币,水资源蓄积功能价值为3.551亿元人民币,水库净化水质总价值为0.816亿元人民币。该水库湿地生态系统,在全部发挥效益后每年所产生的生态服务价值总额为29.946亿元人民币。除了供水功能外,水库的调蓄洪水功能价值最为突出,其次是水资源蓄积功能价值。  相似文献   

6.
[目的] 探索流域生态补偿标准在生态产品价值实现路径中的可操作性,为流域生态环境建设提供理论支撑。 [方法] 以海南省南渡江流域为研究区,基于生态损害赔偿、生态保护补偿理念,将其与InVEST模型和ArcGIS相结合,评估南渡江流域内主要生态系统服务,从生态系统服务变化的角度计算生态补偿标准。 [结果] ① 2015—2020年,南渡江流域内生态系统服务具有明显的空间异质性,中上游地区水源涵养服务、土壤保持服务和水质净化服务能力较强,流域下游地区较低。 ②2015—2020年,流域内水源涵养价值在205.39~260.76亿元之间;土壤保持价值在19.11~20.39亿元之间;水质净化价值在2 782.30~3 233.92万元之间。水源涵养变化量价值在11.50~27.32亿元之间;土壤保持变化量价值在1 137.16~10 365.34万元之间;水质净化变化量价值在7.99~400.59万元之间。 ③根据3种服务功能价值量计算,南渡江流域2016—2020年生态补偿标准为90.62亿元,年生态补偿标准在11.82~28.36亿元之间。 [结论] 2015—2020年,南渡江流域生态系统服务价值在224.81~281.48亿元之间,流域2016—2020年生态补偿标准在11.82~28.36亿元之间。该流域中上游是提供综合生态系统服务的核心区域。  相似文献   

7.
秦岭山地生态系统服务功能价值初步研究   总被引:14,自引:0,他引:14  
运用环境经济学的方法,借助GIS技术,根据秦岭山地自然地理特点,对秦岭山地生态系统分南、北坡对其植被有机物生产、保持土壤、涵养水源、固定二氧化碳、释放氧气及净化环境6种生态服务功能价值进行研究。结果表明:①秦岭山地6种生态服务功能总价值为1014 45亿元/a,其中,北坡为228 63亿元/a,南坡为785 82亿元/a。②南、北坡生态系统单位面积生态服务功能价值存在一定的差异,北坡生态系统单位面积生态服务功能价值高于南坡,但因南坡面积远大于北坡,故南坡生态系统对整体生态系统的服务功能价值贡献较北坡大。③南、北两坡植被在保持土壤、固定二氧化碳、涵养水源等方面都起着重要的作用。提出了生态服务功能价值空间分级方案和保护生态系统的建议。  相似文献   

8.
呼斯太河流域水土保持世行贷款项目实施期为 8年 ( 1994~ 2 0 0 1年 ) ,总投资 85 0 0万元 ,将完成新增治理水土流失面积 2 0 2 7km2 。截至 1999年底 ,6年共完成治理面积 2 3 5km2 ,提前超额完成了任务 ,项目区水土流失治理程度由2 4%提高到 72 9%,土地利用率由 3 2 %提高到 82 0 %,植被覆盖度由 2 5 %提高到 72 %,土地生产力由 1741元 /hm2 增加到 3 75 0元 /hm2 ,人均收入由 62 8元增加到 2 485元 ,已显示出显著的经济、生态、社会效益  相似文献   

9.
随着黄土高原地区退耕还林政策的实施,近十几年西安市植被覆盖情况变化发生了显著变化。为了对西安市植被覆盖变化进行深入的研究,利用Mann-Kendall趋势检验法及Hurst指数、Pettitt检验法分析了2000-2013年来西安市植被覆盖度变化特征,并利用重心转移模型和相对发展率分析了西安市植被覆盖度变化的空间变化差异。结果表明:(1)西安市植被覆盖度中等程度变异面积占总面积10.02%;(2)西安市植被覆盖度呈增加趋势的面积占区域总面积86.54%,具有正向持续性的面积占区域总面积72.62%,35.30%面积植被覆盖度呈持续改善;(3)西安市植被覆盖度突变年份均显著发生在2004年、2005年、2006年、2007年、2008年,发生显著突变年份的面积占总面积的17.58%;(4)西安市植被覆盖度相对发展率空间变化范围为-9.07~7.49,相对发展率的负值占区域总面积的20.77%,西安市植被覆盖度空间重心呈现由西南逐渐向东北方向转移的趋势;(5)西安市降雨量与植被覆盖度均值均呈现增加趋势,相关系数为0.47(p<0.09),空间分布重心呈现从东北向西南转移的趋势,与植被变化呈现相反的趋势。研究成果有助于进一步深化对西安市植被恢复状况及其影响因素的认识,为西安市植被恢复等生态建设工程提供一定的科学依据。  相似文献   

10.
水土保持生态服务功能价值估算   总被引:11,自引:0,他引:11       下载免费PDF全文
以水土保持学、生态学和生态经济学理论为指导,提出水土保持生态服务价值的概念。认为水土保持生态服务价值估算是在特定尺度和区域范围内,将水土保持措施为人类和社会提供的服务进行货币值计量的研究,具体评价内容包括保持和涵养水源价值、保持和改良土壤价值、固碳供氧价值、净化空气价值、防风固沙价值、维持生物多样性价值等6个方面。针对水土保持措施提供生态服务功能的不同表现形式,采用市场价值法、影子工程法、生产成本法、机会成本法等多种价值评估方法,以2004年全国水土流失新增综合治理面积为例,对水土保持生态服务的功能价值量进行估算。初步估算出水土保持措施带来的生态服务价值总量为2117.8亿元,其中,保持与涵养水源价值为406.0亿元,保持与改良土壤价值为889.9亿元,固碳供氧价值为106.9亿元,净化空气价值为183.2亿元,防风固沙价值为172.0亿元,维持生物多样性价值为359.8亿元。在各项价值中,保持与改良土壤和保持与涵养水源的价值最为突出。  相似文献   

11.
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.  相似文献   

12.
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.  相似文献   

13.
To evaluate the feasibility of long-term desert reforestation technology of mixed vegetation, cardon cactus (Pachycereus pringlei) seedlings from indoor and outdoor nurseries were planted in the field adjacent to one seedling of potential legume nurse trees: mesquite amargo (Prosopis articulata), yellow palo verde (Parkinsonia microphylla), and blue palo verde (Parkinsonia florida). Some of the planting holes were also supplemented with common dairy compost. Additionally, the combinations of legume tree–cactus were inoculated with either a consortium of desert arbuscular mycorrhizal (AM) fungi, plant growth promoting bacteria (PGPB; the diazotroph Azospirillum brasilense Cd, and the phosphate solubilizer Paenibacillus sp.), or a mixture of all. The field experiments were evaluated periodically during 30 months for survival and growth. Cardons reared in an outdoor screen house survived better in the field than those reared in a controlled growth chamber and hardened later outdoors. Association with any legume nurse tree increased survival and enhanced growth of untreated cardons. For cardons growing alone, application of either compost, AM fungi, and all the treatments combined increased survival. For these plants, no treatment affected plant growth during the first 3 months after transplanting. Later, all treatments, except for AM fungi, enhanced plant growth. However, only 2 years after transplanting the enhanced growth effect of AM fungi was also significant. In the presence of the legume nurse trees, transient positive effects on cardon growth were recorded. General evaluation after 30 months of cultivation showed that the treatments positively affected cardon growth when growing alone or in combination only with mesquite amargo but not with the other two legume trees. This study proposes that young legume trees have the capacity to enhance survival and growth of cardon cactus, depending on the legume cactus combination. Additional treatments such as compost or PGPB can either amplify the effect or else attenuate it.  相似文献   

14.
Detailed karyotypes and 4C DNA amounts have been studied in five cultivars of Cajanus cajan and 20 species belonging to Cajanus, Rhynchosia, Dunbaria, Flemingia and Paracalyx. C. cajan shows intraspecific variability and its karyotype is most similar to that of C. cajanifolius (sect. Cajanus) in the morphology and number of satellite chromosomes and the lack of any correlation between chromosome size within the complement and asymmetry. Karyotypes of C. lineatus and C. sericeus belonging to sect. Atylia are similar with respect to maximum r-index and the ratio of longest and shortest chromosomes in their respective complements. C. acutifolius (sect. Frutocosa) is distinct in having a very low ratio (1.44) between the longest and the shortest chromosomes, while in C. albicans, C. goensis, C. scarabaeoides (sect. Cantharospermum) there is no chromosome pair with r-index >2.0. C. mollis and C. volubilis (sect. Volubilis) show similarity with regard to ratio between the longest and the shortest chromosomes and a distinct chromosome pair with an arm ratio of 2.7 and C. platycarpus is distinct (sect. Rhynchosoides) in having the smallest ratio (1.36) between the longest and the shortest chromosomes. 4C DNA amounts in Cajanus and Rhynchosia vary between 3.28 pg to 11.69 pg and 4.92 pg to 11.13 pg respectively, while in Dunbaria, Flemingia and Paracalyx these vary between 4.70 and 7:06 pg. In the genus Cajanus karyotypic features and 4C DNA amounts agree with the sectional classification and bring out a close relationship between C. cajan and C. cajanifolius. This is supported by studies based on seed protein patterns, isozyme analysis, trypsin and chymotrypsin inhibitor patterns, RFLP and RAPD data and crossability relationships. A clear relation between DNA amount and abnormalities effecting the extent of pairing and recombination in interspecific hybrids shows the importance of this study in developing future breeding programme involving C. cajan and its wild relatives that are of potential value.  相似文献   

15.
Several commercial fungicide seed treatments were evaluated for their possible effect on the survival of Bradyrhizobium japonicum on seeds and on the nodulation and yield of soybeans in a greenhouse and a field experiment. quinolate Pro (carbendazim and oxine copper), Vitavax 200FF (carboxin and thiram), and Monceren (pencycuron) had a small effect or no effect on the survival of B. japonicum and on the nodulation and yield of soybeans. They can thus be considered compatible with soybean seed inoculation. Germipro UFB (carbendazim and iprodione), Apron 35J (metalaxyl), and Tachigaren (hymexazol) decreased B. japonicum survival and the nodulation and yield of soybeans and thus cannot be considered compatible with soybean seed inoculation.  相似文献   

16.
Während neunjähriger (1994-2002) Untersuchungen in der Versuchsanstalt Ba?cyny (Fahlerde, Fall-Gleyboden, ausgebildet aus leichtem Lehmboden) wurde der Befall mit Krankheiten an der Zuckerrübe in Abhängigkeit von der Düngungsmethode bewertet. Folgende Methoden wurden angewendet: A - Mineraldünger, B - Stalldung und Mineraldünger, C - Stroh-, Gründung und Mineraldünger, D - Kompostdünger und Biopräparate (ökologische Düngung). Auf den Objekten A, B, C wurden bei konstanter Phosphor-Kalium-Düngung die Stickstoffgaben von 0 bis 180 kg.ha?1 differenziert. Auf dem ökologischen Objekt D ohne Mineraldünger wurden statt Stickstoff die Biopräparate P500 und P501 verabreicht. Der geringste Befall von Krankheiten wurde an der Zuckerrübe auf jenem Objekt festgestellt, das mit Kompost und den Biopräparaten gedüngt worden war. Im Rahmen der konventionellen Düngungsmethoden wurde allgemein die höchste Intensität der Krankheiten an der mit Stroh, Gründung und Mineraldünger gedüngten Zuckerrübe beobachtet. Ausnahmen von dieser Regel bildete das Vorkommen von echtem Mehltau und Keimlingsfäule. Auf den Objekten A, B, C nahm die Intensität der Krankheiten mit der Steigerung der Stickstoffgabe zu. Auch die auf Objekt D verabreichten Biopräparate stimulierten die Entwicklung der Krankheiten. The effect of various fertilization methods on the diseases of sugar beet was estimated on the basis of nine-year studies (1994-2002) conducted in the Experimental Production Farm in Ba?cyny on loess-based, sedimentary-gley, light-clay soil. The following fertilization methods were applied: A - mineral fertilization, B - mineral and manure fertilization, C - straw, green manure and mineral fertilization, D - ecological compost and biodynamic preparations fertilization. In the objects A, B and C fertilized with phosphorus and potassium, various doses of nitrogen ranging from 0 to 180 kg/ha?1 were used. In the ecological object D, where mineral fertilization was not used, biodynamic preparations P500 and P501 were applied instead of nitrogen. The lowest ratio of the diseases of sugar beet was observed in the object fertilized with the compost and biodynamic preparations. In view of the conventional fertilization methods, generally the highest incidence of diseases was noted in the sugar beet fertilized with straw, green manure and mineral fertilizers. The exception was the occurrence of powdery mildew and the black leg. In objects A, B and C the incidence of the diseases increased with the increase in nitrogen doses. The applied biodynamical preparations in the object D stimulated the development of diseases too.  相似文献   

17.
Summary Damping-off of lettuce (Lactuca sativa) caused by Pythium ultimum was studied in pots containing a non-sterile potting mix in the glasshouse. Fifty P. ultimum sporangia g-1 compost reduced the plant stand to 15% and shoot dry weight to 18%, but this reduction was totally prevented by applying Trichoderma harzianum at 2×105 viable propagules g-1 potting mix. Gliocladium virens and Enterobacter cloacae also alleviated the damping-off. E. cloacae did not adversely affect the action of the fungal antagonists. The co-existence of the bacterial and fungal antagonists was revealed on the root surface and inner surface of the testa by scanning electron microscopy, indicating the compatibility of the biocontrol agents.  相似文献   

18.
细菌、真菌及植物氮营养信号研究进展   总被引:1,自引:0,他引:1  
氮素吸收代谢是所有生物生命活动的核心部分,因此,各种生物对氮的吸收与同化过程都有精细的调节。这种调节依赖于生物对体内氮素状况信号及体外(生长介质中)氮素信号的感受。过去几十年中,在细菌、真菌中已经对氮素营养信号有了较好的研究,而植物中则相对缓慢,但也有了一定的认识。本文重点比较细菌、真菌及植物中氮信号系统的组成,以期为进一步认识植物中的氮信号接受与转导系统提供启示。  相似文献   

19.
Aircraft operations have the potential to disturb and to impact negatively on bird life. A gradient of increasing behavioural response is evident in birds when exposed to increasing aircraft stimulus. The most major disturbance is likely to lead to impacts on the health, breeding performance and survival of individual birds, and perhaps bird colonies. A process of revision to policies on aircraft operations contained in management plans for a number of specially protected areas in Antarctica by the United Kingdom, accompanied by consultations made within the scientific community through the Scientific Committee on Antarctic Research (SCAR) and with operational interests through the Council of Managers of National Antarctic Programmes (COMNAP) resulted in new guidelines being adopted by the Antarctic Treaty Consultative Parties in June 2004. The principal recommendations of the guidelines are that bird colonies should not be overflown below 2000 ft (∼610 m) above ground level and landings within 1/2 nautical mile (∼930 m) of bird colonies should be avoided wherever possible. These guidelines are less stringent and less specific than those that were recommended by the SCAR specialist group on birds, and represent a compromise to accommodate operational needs. While the adoption of clear and consistent guidelines for the operation of aircraft in Antarctica is welcome in that this provides practical advice that is likely to reduce incidences of close aircraft/bird encounters, there remains insufficient knowledge of the interactions between aircraft and birds in Antarctica, and the consequent impacts on individual birds and on bird populations. It is important, therefore, that the guidelines adopted are considered interim, and should be kept under scrutiny with revisions made as new and improved research results appear.  相似文献   

20.
Summary Algal populations were quantified (as colony-forming units [CFU] per square centimetre) in 102 samples of rice soils from the Philippines, India, Malaysia and Portugal, and in 22 samples of soil-based inocula from four countries. Heterocystous blue-green algae (BGA) were present in all samples. Nostoc was the dominant genus in most samples, followed by Anabaena and Calothrix. In soils, heterocystous BGA occurred at densities ranging from 1.0 × 102 to 8.0 × 106 CFU/cm2 (median 6.4 × 104) and comprised, on average, 9% of the total CFU of algae. Their abundance was positively correlated with the pH and the available P content of the soils. In soil-based inocula, heterocystous BGA occurred at densities ranging from 4.6 × 104 to 2.8 × 107 CFU/g dw (dry weight), comprising only a moderate fraction (average 13%) of the total algae. In most soils, the density of indigenous N2-fixing BGA was usually higher than that attained by applying recommended rates of soil-based inoculum. Whereas research on the practical utilization of BGA has been mostly directed towards inoculation with foreign strains, our results suggest that attention should also be given to agricultural practices that enhance the growth of indigenous strains already adapted to local environmental conditions.Maître de Recherches ORSTOM (France), Visiting Scientist at IRRI  相似文献   

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