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1.
This paper proposes an approach for assessing the effectiveness of those agri-environmental schemes and rural development measures aimed at enhancing the natural value of farmland and, more generally, aimed at releasing the pressure on the environment due to agriculture. First, based on fine scale data, indicators derived from the High Nature Value farmland concept are tested at different scales, resolutions and situations: LAU2 for The Netherlands and LAU1 for France. The effect of rural development measures on the evolution of these indicators is then explored. Significant cause-effect relationships are found in the French cases, while only relationships of correlations are observed from the Dutch case study, obviously caused by a lack of data. Using fine scale data on rural development measures related to both 2000–2006 and 2007–2013 programming periods of the Common Agricultural Policy, a spatial econometrics methodology is applied to France, at national level on the one hand, and at a selected NUTS2 level on the other. The results indicate that agri-environmental schemes and specific rural development measures affect the changes in the indicators, and that the spatial scale of the analyses matters. In particular, results indicate that trends observed at the national scale do not necessarily apply at the regional scale (e.g. impacts of conversion to organic farming, the grassland premium, payments for water and biodiversity protection) underlining the importance of multi-scale assessments. Interestingly, delayed effects of the measures implemented in the 2000–2006 programming period, such as machinery investment aids and less-favoured area payments, are detectable. As regards the 2007–2013 rural development measures, the most significant positive effects on the farm nature value indicator are found, at the national level, for locally targeted agri-environmental schemes focused on biodiversity and water issues and, at the NUTS2 level, for supporting organic farming schemes. Given that the farm nature value indicator is built from three different indices (addressing crop diversity, grassland share, and wooded and afforested farmland) the effect of rural development measures on each of these individual indices is also explored. This enables the main structure and the magnitude of policy impacts to be captured and helps with the understanding of why certain objectives were not met. Key findings are relevant in the context of policy monitoring and evaluation, while the methodology proposed, that incorporates spatial effects, is an important contribution to the implementation of the Common Monitoring and Evaluation Framework by Member States to account for national, regional or local characteristics.  相似文献   

2.
The objective of this article is to assess the condition of and hazards to the natural environment in selected landscape parks in Poland with respect to the impact of agricultural management using the DPSIR method. Our proposed set of indicators, based on generally available and applicable data, shows at the local scale, in a simple way, the condition of functioning of the balance between the natural environment and agricultural management and it assesses the level of repair works in the context of the records of the environmental protection program. The highest negative impact of agricultural management in the areas studied is noticed in the soil environment as well as the contexts of biodiversity and landscape. On the other hand, the lowest influence of agricultural economy was noted in the cases of the atmosphere and hydrosphere. The results of the aggregated indicators also showed lower or higher dependencies between the coverage and the use of the area in landscape parks and the condition of particular elements of the environment and the landscape.  相似文献   

3.
The abandonment of traditional anthropogenic activities is an important driver shaping landscape patterns. Therefore, multi-scale pattern analysis over time is needed to identify appropriate scales for biodiversity conservation and monitoring of abandoned landscapes. We compared spatial and temporal changes in a pair of alpine watersheds in Italy (Cajada and Tovanella), which are similar in size, geo-climatic conditions, and land-use histories; but have had divergent anthropogenic abandonment processes since the 1950s. We hypothesize that this divergence has led to corresponding dissimilarities in multi-scale patterns of landscape change. To examine this hypothesis, we analyzed land cover maps from three years (1954, 1980/83, 2006) and described the changes using transition matrices. For each year and watershed, landscape heterogeneity and a set of class-level metrics (i.e. percentage of the landscape, area-weighted mean patch size, patch density, area-weighted mean shape index, edge density, and aggregation index) were also measured at different scales using random sampling techniques, and the results were summarized by using scalograms. Woodland expansion occurred mainly at the expenses of grasslands, meadows, and shrublands. These changes were greater during the first time-period (1954-80/83) than in the more recent period (1980/83-2006), with a mean annual value that decreased from +5.18 to +1.33 ha/year and from +4.08 to +1.96 ha/year in the abandoned and managed watersheds, respectively. Landscape heterogeneity decreased over time with a similar pattern in both watersheds, which indicates a general process of homogenization. Management regime affected the spatial-scale response of class-level metrics; these metrics showed a variety of multi-scalar responses, which were not always consistent over time and under different management regimes. When considering the response of the indices across spatial-scales for both watersheds, certain historical curves showed a scale break, representing a significant change in the shape and slope of the curve (i.e. scale divergence). The presence of scale breaks in the scalograms can potentially reveal important thresholds for biodiversity. For example, grassland and meadow patch density at small spatial scales (<200 m radius), which was found to be important for protected butterfly species, had a greater reduction over time in the managed watershed when compared to the abandoned watershed. In conclusion, the findings of this study indicate that there is good potential for understanding changes in landscape patterns under different management abandonment regimes by combining spatial and temporal analysis of class-level metrics.  相似文献   

4.
Successful conservation initiatives require collaboration between stakeholders across a range of organisational foci and expertise. In Romania, the EU LIFE Nature programme is the most important financing instrument for nature conservation, and projects commonly involve partnerships between public authorities, NGOs, enterprises, and research institutions. To understand strengths and gaps in conservation partnerships for LIFE Nature projects implemented in Romania, we applied a Social Network Analysis approach to 85 partner organisations across 35 projects. We complemented this approach with a questionnaire directed to project managers to identify the criteria for selecting partners, and the role of partners in the project. The network included mostly public authorities (50%), yet the Romanian Ornithological Society (NGO) and the University of Bucharest were the most influent organisations in the network. Public authorities, park authorities, and enterprises were often selected as partners because of their financial contributions and local connections. In contrast, research institutions and NGOs were selected as partners because of their technical expertise and policy influence at the national level. Furthermore, research institutions, parks authorities and NGOs were involved in proposal writing, preparatory and management activities, while public authorities had no predefined roles in LIFE projects. The analysis also showed that the Romanian conservation system is polycentric, with influence shared between research organisations, NGOs, and public authorities. Interviews with project managers revealed that Romania submits relatively fewer projects compared to Western EU countries because public agencies have low technical and logistic capacity. We recommend a national level strategy for increasing project submission rates and quality of proposals that addresses the need for strengthening ties between core organisations and public authorities, especially at the local level. These findings are likely to be applicable to other EU member states that are currently struggling to get funding for conservation projects, ultimately moving the EU closer to achieving the European Union Biodiversity Strategy 2020 targets.  相似文献   

5.
Soils are one of the most important features of the natural capital of terrestrial ecosystems. There is a strong and increasing policy requirement for effective monitoring of soils at local, regional and national-scales. However, it remains unclear which properties of soils are most appropriately monitored. This is partly due to the wide range of goods and services that soils provide, but also their inherent chemical, physical and biological complexity. Given that the biota plays such fundamental roles in the majority of ecosystem services provided by soils, biological properties are logical candidates as effective indicators, to complement soil physico-chemical properties. A plethora of biological methods have been suggested as indicators for monitoring soils but few are used in national-scale monitoring or are published as international standards. A framework for selecting ecologically relevant biological indicators of soil quality, for national-scale soil monitoring, that cover the range of functions and services of soil was devised. The literature was surveyed to identify 183 candidate biological indicators which were then scored by experts and stakeholders against a wide range of scientific and technical criteria. The framework used the scores and weightings to then rank, prioritise and select the indicators. This semi-objective approach using a “logical sieve” allowed repeated iterations to take account of end-user requirements and expert opinion. A ranked list of 21 indicators was produced that covered a range of genotypic-, phenotypic- and functional-based indicators for different trophic groups. Four of these were not deemed sufficiently robust for ready deployment in a national-scale monitoring scheme without further methodological development. The suite of indicators identified offers the strongest potential candidates for deployment in national-scale soil monitoring schemes. However, standard operating procedures, their inherent sensitivity, ability to discriminate between soil:land use combinations, ecological interpretation all need to be confirmed. The power of the approach adopted here is that it provides a clear record and audit trail on the decision-making process, enables different priorities to be set contingent on the nature of the desired monitoring, and can direct and allow the inclusion of further methods or indicators into the framework.  相似文献   

6.
7.
Sustainable use of tropical forest systems requires continuous monitoring of biological diversity and ecosystem functions. This can be efficiently done with early warning (short-cycle) indicator groups of non-economical insects, whose population levels and resources are readily measured. Twenty-one groups of insects are evaluated as focal indicator taxa for rapid assessment of changes in Neotropical forest systems. Composite environmental indices for heterogeneity, richness, and natural disturbance are correlated positively with butterfly diversity in 56 Neotropical sites studied over many years. Various components of alpha, beta and gamma-diversity show typical responses to increased disturbance and different land-use regimes. Diversity often increases with disturbance near or below natural levels, but some sensitive species and genes are eliminated at very low levels of interference. Agricultural and silvicultural mosaics with over 30% conversion, including selective logging of three or more large trees per hectare, show shifts in species composition with irreversible loss of many components of the butterfly community, indicating non-sustainable land and resource use and reduction of future options. Monitoring of several insect indicator groups by local residents in a species-rich Brazilian Amazon extractive reserve has helped suggest guidelines for cologically, economically, and socially sustainable zoning and use regimes.  相似文献   

8.
9.
AIMS: Determine the occurrence and levels of pathogens and indicators in raw and treated sludges and compare their persistence after two different treatments. METHODS AND RESULTS: Helminth ova, Cryptosporidium spp., Salmonella spp., enteroviruses, and bacterial and viral indicators were determined in raw sludges and biosolids produced after mesophilic and thermophilic treatments. Except Salmonella, all of the parameters were quantified. Helminth ova were found at very low concentrations even in raw sludges. Viable Cryptosporidium oocysts were still present in most samples of treated sludges. Faecal coliforms, spores of sulphite-reducing clostridia (SSRC), and somatic coliphages were the only indicators with values above their detection limits in most of the samples. CONCLUSIONS: Pathogens were still detected in some treated sludge samples. SSRC were the most resistant micro-organisms to treatments and hence may be an indicator for the reduction of protozoan oocysts. Somatic coliphages constitute an alternative as viral indicators due to their detection in sludges before and after treatment. SIGNIFICANCE AND IMPACT OF THE STUDY: Because of the persistence of some pathogens after sludge treatments, additional indicators are needed. SSRC and somatic coliphages are good candidates. Easy and inexpensive methods for the determination of these indicators are feasible both in industrialized and developing countries.  相似文献   

10.
J. Liira  K. Kohv 《Plant biosystems》2013,147(1):211-220
Abstract

We quantified the effects of anthropogenic disturbances on the structure and biodiversity of boreal forests on acidic soils and created a statistically supported rational set of indicators to monitor the stand “naturalness”. For that, we surveyed various traits of tree layer, understory, herb layer, forest floor and several widely accepted biodiversity epiphytic indicators in 252 old‐aged boreal stands in Estonia, mostly dominated by Scots pine or Norway spruce. Multifactorial general linear model analyses showed that many forest characteristics and potential indicators were confounded by the gradient of soil productivity (reflected by the forest site type), local biogeographic gradients and also by stand age. Considering confounding effects, boreal forests in a near‐natural state have more large‐diameter trees (diameter at breast height >40 cm) and larger variety of diameter classes, higher proportion of spruce or deciduous trees, a larger amount of coarse woody debris in various stages, a more closed tree canopy and denser understory than managed mature forests. By increasing light availability above the field layer, forest management indirectly increases the coverage of herbs and lichens on the forest floor but reduces the alpha‐ and beta‐diversity of herbs and the proportion of graminoids. Human disturbances reduce the relative incidence of many commonly accepted biodiversity indicators such as indicator lichens, woodpeckers, wood‐dwelling insects or fungi on trees. The test for the predictive power of characteristics reacting on disturbance revealed that only a fraction of them appeared to be included in a diagnostic easy‐to‐apply set of indicators to assess the nature quality of boreal forest: the amount of dead wood, the proportion of deciduous trees, the presence of specially shaped trees and woodpeckers and, as an indicator of disturbances, the forest herb Melampyrum pratensis. Many of these indicators have already been implemented in practice.  相似文献   

11.
The language of ecosystem science is pervaded by value-laden terms such as pristine, fragile, disturbance, balance, dominance and alien species. Such terms have high status and are often used in the rhetoric of the conservation ethic. Here, I consider the possibility of the use of less value-laden terms such as change, increase, decrease and so on. This would distinguish between values and perceived trends or states and leave ecosystem science to deal with what is verifiable. However, I also consider the opposite point of view, in that the value-laden terms, like 'the balance of nature', relate to how a wide range of people feel about nature and are effective emotive motivators of the conservation ethic in society, providing a common language for a discourse between ecosystem scientists and other people.  相似文献   

12.
In the past decade, there has been increased scientific interest in the so-called organic farming, especially in comparison with conventional agriculture. Many recent studies compare these two fundamentally different systems for soil properties, in different regions of the world. In this study, two adjacent fields in Central Italy, one managed according to organic, and the other according to conventional farming methods, were studied to determine the effects of these two agricultural systems on soil quality indicators at the farm level. Chemical and microbiological properties were chosen as indicators of soil quality and were measured at soil depth intervals of 5–20 and 20–35 cm, after 7 years of organic certified and conventional management methods. The field under organic management showed significantly better soil nutritional and microbiological conditions; with increased level of total nitrogen, nitrate and available phosphorus, and an increased microbial biomass content, and enzymatic activities (acid phosphatase, protease and dehydrogenase). No consistent increase in total organic carbon was observed. Results of the study suggest that, over the period of 7 year, organic management method strongly affects soil quality indicators. Large differences between the two soils were found in terms of microbiological properties, which are sensitive soil indicators of changes occurred under the different farming systems.  相似文献   

13.
生物多样性不同层次尺度效应及其耦合关系研究进展   总被引:4,自引:0,他引:4  
彭羽  卿凤婷  米凯  薛达元 《生态学报》2015,35(2):577-583
生物多样性包含遗传、物种、生态系统和景观多样性4个层次,虽然各个层次的研究较多,但是各层次间相互关系的研究较少。物种多样性多采用野外样方调查法,景观多样性采用遥感、地理信息系统和野外调查,研究方法较为成熟;生态系统多样性研究因生物地理地域和尺度的不同,常采用不同的分类体系,尚无统一评估标准。物种多样性的尺度效应在α、β、γ指数上均有不同体现,景观多样性的尺度效应非常明显。生境异质性与物种α和β多样性指数密切相关,在一定尺度上,丰富的景观多样性提高了物种多样性。未来研究需要揭示不同生物多样性层次之间的耦合关系,并将研究结果应用到生态系统红色名录制定、区域生物多样性综合监测与评估等实践之中。  相似文献   

14.
15.
Summary Laboratory incubation experiment was conducted with a clay loam alluvial lowland rice soil to study the relative effectiveness of two sources of Zn (ZnEDTA and ZnSO4) in maintaining Zn availability in soil under two moisture regimes (saturated and waterlogged) both in presence as well as absence of added organic matter. The results showed that ZnEDTA was always more effective than ZnSO4 in maintaining higher amount of zinc in available form in soil for a longer perid. Results of greenhouse experiment conducted with rice showed that concentration and uptake of Zn by roots were generally higher with ZnEDTA than with ZnSO4 both in presence and absence of added organic matter, whereas in respect of shoot this was true only in absence of added organic matter.  相似文献   

16.
Considering the on-going strive towards new, alternative indicators to measure our societal development pathways, and the fact that policy indicators remain largely enigmatic with regard to their patterns of embeddedness in institutional decision-making processes, it appears necessary to work towards reducing our lack of understanding of their interactions with policy-making. In the present paper, we focus on exploring the significance of composite indicators for policy making in the particular policy environment of the EU-institutions. Our research is underpinned by the conviction that such indicators are not systematically used directly, but have an indirect influence on policy making that needs to be better understood. Our analytical framework – in order to analyse the ways in which composite indicators enter policy processes – is characterised by the distinction between the ‘use’ and the ‘influence’ of indicators on the one hand, and on the other hand between 3 types of factors: indicator factors, policy factors and user factors. Our empirical results show that while most of the academic attention and political debate around indicators has tended to focus on ‘indicator factors’, such quality attributes actually mattered relatively little in our setting as determinants of indicator influence. This rejects the idea that the robustness of evidence would lie exclusively in its technical quality and in the independence of its producer, and instead calls attention to the processes of evidence-construction. Simultaneously, ‘user factors’ (beliefs and representations of policy actors) and ‘policy factors’ (institutional context) were crucial as explanatory factors of the policy mechanics we identified.  相似文献   

17.
The focus on place rather than space provides geography with a powerful raison d’être. As in human geography, the functional role of place is integral to the understanding of evolution, persistence and extinction of biotic taxa. This paper re‐examines concepts and biogeographical evidence from a geographical rather than ecological or evolutionary perspective. Functional areography provides convincing arguments for a postmodern deconstruction of major principles of the dynamic Equilibrium Theory of Island Biogeography (ETIB). Endemic oceanic island taxa are functionally insular as a result of long‐term island stability, confinement, isolation, and protection from continental invasion and disturbance. Most continental taxa persist in different, more complex and open spatial systems; their geographical place is therefore fundamentally distinct from the functional insularity of oceanic island taxa. This creates an insular‐continental polarity in biogeography that is currently not reflected in conservation theory. The focus on the biogeographical place leads to the development of the eigenplace concept defined as the functional spatial complex of existence. The application of still popular ETIB concepts in conservation biology is discouraged. The author calls for the integration of functional areography into modern conservation science.  相似文献   

18.
Agroecosystems have traditionally been considered incompatible with biological conservation goals, and often been excluded from spatial conservation prioritization strategies. The consequences for the representativeness of identified priority areas have been little explored. Here, we evaluate these for biodiversity and carbon storage representation when agricultural land areas are excluded from a spatial prioritization strategy for South America. Comparing different prioritization approaches, we also assess how the spatial overlap of priority areas changes. The exclusion of agricultural lands was detrimental to biodiversity representation, indicating that priority areas for agricultural production overlap with areas of relatively high occurrence of species. By contrast, exclusion of agricultural lands benefits representation of carbon storage within priority areas, as lands of high value for agriculture and carbon storage overlap little. When agricultural lands were included and equally weighted with biodiversity and carbon storage, a balanced representation resulted. Our findings suggest that with appropriate management, South American agroecosystems can significantly contribute to biodiversity conservation.  相似文献   

19.
In this paper, we propose a new system for understanding the biodiversity in different conservation areas. It includes three aspects: the capacity, the connectivity and the quality. The capacity refers to the numbers of biodiversity, including absolute and relative richness of the vegetation types N v and D v =(N v −1)/lnA, species numbers S and richness of species d Gl =(S − 1)/lnA, and germ plasm resources within a nature reserve, and also the potential biological living space offered by the natural resource. It comprises the total biological resources in a nature reserve. The connectivity refers to the flux of biodiversity, including similarity and connected status of the vegetation types SI Li =2z/(x + y) and species numbers SI C =2z/(x + y) among different nature reserves. The quality refers to the stability of biodiversity, including relative species richness index RS Li =d/d max, relative vegetation richness index RV Li =D v /D maxv , fastness to invasion species ƒ Li =1−S i /S t , weighted values, representativeness and vulnerability of special vegetations, special species, CITES species and rare species as the protected targets.  相似文献   

20.
In this paper,we propose a new system for understanding the biodiversity in different conservation areas.It includes three aspects:the capacity,the connectivity and the quality.The capacity refers to the numbers of biodiversity,including absolute and relative richness of the vegetation types Nv and Dv = (Nv-1)/lnA,species numbers S and richness of species dGI = (S- 1)/lnA,and germ plasm resources within a nature reserve,and also the potential biological living space offered by the natural resource.It comprises the total biological resources in a nature reserve.The connectivity refers to the flux of biodiversity,including similarity and connected status of the vegetation types SILi = 2z/(x + y) and species numbers SIc = 2z/(x + y) among different nature reserves.The quality refers to the stability of biodiversity,including relative species richness index RSLi = d/dmax,relative vegetation richness index RVLi =Dv/Dmaxv,fastness to invasion species fLi = 1-Si/St,weighted values,representativeness and vulnerability of special vegetations,special species,CITES species and rare species as the protected targets.  相似文献   

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