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1.
It is expected that the application of a restrictive legal instrument would be an important barrier to human pressures on protected areas in Brazil. One aspect that remains to be determined is whether the applied restrictions will be related to the quality of scenarios at the borders of protected areas. The objective of this work was to analyze the capacity for minimizing the impacts on two protected areas and to identify the effective function of the barrier imposed by an environmental legal border. The borders of two protected areas, the Despraiado Sustainable Development Reserve and the Jureia-Itatins State Ecological Station, as well as the corresponding buffer zone were studied. The historical evolution of the land cover/land use of these regions was analyzed by dividing the regions into 900 m2 hexagonal units. The scenarios for the years 1962, 1980 and 2007 were overlaid for each hexagon. The hexagons were classified according to the possible effects of conservation, and the results were quantified in terms of the frequency of land use and ecological flows. A simulation of future land use in 2028 was performed using the Kappa index, Markov chain modeling, multi-criteria analysis and cellular automata modeling. Based on the trend for the last 45 years, a very dynamic interaction at the legal boundaries was identified; in certain cases, either conservation or degradation were stimulated, and the intended objectives of legal environmental measures were never fulfilled. The simulation showed that by 2028, the frontiers of these protected areas will retain less than 10% of the natural vegetation cover, and 43% of this area will be covered with banana plantations.  相似文献   

2.
Successful land claims on protected areas by previously disenfranchised communities often result in co-management agreements between claimant communities and state conservation agencies. South Africa, in particular, has pursued co-management as the desired outcome of land claims on its protected areas. We review four cases of co-management on protected areas in South Africa, and reflect on the appropriateness of the pursuit of co-management as the preferred outcome of land claims. Despite promises of pro-poor, democratically informed management, the practical experience of co-management has seen the continuation of the status quo in terms of conservation, with very few material benefits for claimant communities and limited sharing of responsibilities and decision-making functions. The findings underscore two deep challenges facing co-management in cases of land claims worldwide. First, during land claims negotiations in cases involving protected areas, the state cannot be expected to represent the best interests of its citizens (the land claimants), while simultaneously seeking to meet national and international obligations for protected area coverage. Second, the concept of democratic co-management may sit uncomfortably beside the realities of managing loss-making protected areas with ever-shrinking conservation budgets. Where co-management agreements have already been signed, ensuring that new landowners do indeed have a say in management should form the driving focus for co-management practice going forward.  相似文献   

3.
Several governments in Europe have explicit ambitions to increase societal engagement in the management of Natura 2000 areas. However, implementing this ambition in practice remains a challenge. This article reviews experiences in three Natura 2000 sites in countries in which local level policies exist to improve societal engagement. By defining the elements of the different policies employed in terms of storylines, instruments, organizational structure and style of interaction, and evaluating to what extent these address societal and governmental arguments for societal involvement, wider lessons are drawn on how governments might tackle this complex issue. The area cases show that a hierarchical governance mode is combined with governance modes that are based more on cooperation, market mechanisms or responsiveness to societal energy in order to achieve societal engagement that goes further than acceptance of nature designations.  相似文献   

4.
The semiarid region in the state of Sergipe, Brazil, approximately 11,000 km2, has experienced high deforestation rates in the last decades, which ultimately contribute to global climatic changes. The valuation of ecosystem services of CO2 sequestration can support definition of environmental policies to decrease deforestation in that region. This study aimed to assess land use and land cover changes in the Sergipe semiarid region between 1992 and 2017 by applying remotely sensed data and technics; simulate the land use and land cover changes between 2017 and 2030 by applying a cellular automaton model, by assuming current land use trends (Business as Usual – BAU) as a reference scenario, and a more conservative scenario (Protected Forest – PF), in which was assumed an effective enforcement of the Brazilian Forest Code established in 2012; simulate the carbon stocks by 2017 assuming the BAU and PF scenarios by 2030, and estimate the Carbon balance between the 2030 and 2017 scenarios; and estimate the economic valuation of carbon emission and sequestration by using the InVEST software. The results showed that agriculture (cropped lands) was main driver of the landscape changes in the study area, which increased 14% by 2017, a net increase of 1494.45 km2. The results showed that the total Carbon emissions would reach 736,900 Mg CO2-eq by assuming the BAU scenario, which would increase the cost of opportunity up to US$ 17.7 million and a social carbon cost varying between US$ 10.3 and US$ 30.2 million. The restoration of the permanent preservation areas could contribute to increase Carbon sequestration up to 481,900 Mg CO2-eq by 2030, which is equivalent cost of US$ 11.6 million. The natural landscape in the Sergipe semiarid region was strongly affected by deforestation activities occurred between 1992 and 2017. It requires, therefore, effective actions to support and promote restoration of degraded areas. The forested areas within the Sergipe semiarid region were the most affected type of vegetation because of expansion of agricultural fields soil exposures (Exposed Land). Environmental assessments based on scenarios and economic valuations can provide crucial information to support policy and decision makers to improve strategies for environmental management and conservation.  相似文献   

5.
To restore China’s degraded environment and improve ecological balance, the government launched a land use policy known as the Grain for Green Program (GFGP), which is the largest ecological construction project in China or anywhere else. It has greatly increased the vegetation cover on the Loess Plateau but occupied the space of agricultural development (AD) over the years. Research on the impact of policy implementation on ecosystem services (ESs) and their trade-offs can support scenario analyses that provide realistic guidance for decision makers to formulate future regional ecological restoration planning. Our focus is Ningwu County and Jingle County on the Loess Plateau, a typical ecologically fragile and impoverished area where expansion of vegetation cover has driven extensive loss of farmland and its benefits to farmers.In this study, soil conservation (SC), water yield (WY), habitat quality (HQ), and food supply (FS) were selected to assess the change of ESs and their trade-offs in different scenarios that represent ecological restoration and land reclamation policies. The results revealed that overall ESs had the largest increase but there were more trade-offs among ESs under the GFGP scenario. For a single ESs, SC and HQ were increased while FS and WY were decreased under the GFGP scenario. From the view of trade-offs, the GFGP scenario exhibited more trade-offs than the AD scenario. Furthermore, compared to the GFGP scenario, the numbers of sub-watersheds with trade-offs of ESs decreased under the AD scenario. With more concern about the contradiction between implementing GFGP and protecting farmland, we confirm that it is extremely unwise to incessantly implement GFGP to improve overall ESs without considering the trade-offs among ESs. Given the certain sub-watersheds mainly developing agriculture, the AD scenario appears to best reduce trade-offs among ESs and ensure the improvement of ESs. Therefore, it is of great significance to realize the win-win situation of regional ecological and resource demand to find the most suitable development direction in the future.  相似文献   

6.
Tree species richness, diversity index, standing biomass and biomass carbon stocks were estimated in six villages located under three agro-ecological zones, namely, coastal, hill and plains of Uttara Kannada district, Western Ghats, Peninsular India. The study showed that land use categories other than forest support higher tree species diversity. High basal area, standing biomass and carbon stock in non-forest land categories indicates their potential as carbon sinks and for promotion of species diversity. Inclusion of other non-forest land use categories in afforestation programmes for promotion of multipurpose tree species for conservation of diversity and for enhancing carbon sinks is suggested. There is a need to promote synergy between biodiversity conservation and carbon sequestration under carbon mitigation projects.  相似文献   

7.
滇西北地区耕地利用存在的问题及对策   总被引:4,自引:2,他引:4  
滇西北地区山高坡陡,区位特殊,耕地总量少,坡耕地多,陡坡种植面积大,农业生态环境脆弱。随着滇西北地区保护与发展行动计划在该区域实施,必须加大投入力度,加快基本农田建设步伐,彻底改善农业生产条件,提高耕地单位面积产量。同时要加快退耕还林还草,改善区域生态环境。  相似文献   

8.
Cropland abandonment accompanying economic development has been observed worldwide. China has experienced a large amount of land abandonment in recent years. However, the reasons for it are not entirely clear. Although abandonment decisions are made by individual households, the underlying conditions reflect processes operating at multiple levels. Therefore, we aimed to detect the influences on land abandonment at the parcel, household and village levels. We developed and employed a multi-level statistical model using farm household survey data and geographical maps of Wulong County. Our model revealed that of the variance in occurrence of land parcel abandonment, 7% and 13% can be explained at the household and village levels, respectively, while the remnant 80% can be explained at the land parcel features itself. We found that land abandonment is more prone to occur on parcels that are on steep slopes, have poor quality soil, or are remote from the laborers’ residences. Households with less agricultural labor per unit land area showed a high probability of land abandonment. We also found a nonlinear influence of labor age on land abandonment, with households comprising middle-aged laborers having a low land abandonment probability. Parcels in villages with high elevation, far from the county administrative center or with low prevalence of leased land are inclined to abandonment. We also found, surprisingly, that the household proportion of males among its agricultural laborers did not significantly influence the occurrence of land abandonment at the parcel level, probably due to the male agricultural laborers being overwhelmingly old (average age greater than 56 years). To alleviate land abandonment, we suggest improving land tenure and transfer security to ensure stable access to the land rental market, and also improving infrastructure in remote regions.  相似文献   

9.
In the past few years, urban growth has affected vast agricultural areas, especially in some European regions (EEA, 2006). In peri-urban areas, land consumption is particularly intense, exposing agriculture to the risk of land loss. Assuming the action of different factors, both exogenous and endogenous, on the agricultural system, the potential risk of land use conversion is measured by the Sensitivity Index of Agricultural Land (SIAL), an innovative tool for territorial analysis. In the following paper, the SIAL will be presented with an application for a metropolitan area. In this case study, the exogenous variables of urban proximity seem to be those most involved in the processes of conversion from agricultural to urban land use.  相似文献   

10.
Agricultural intensification and abandonment have been identified as two of the more prominent and polarizing drivers of landscape change in Europe. These transitions may induce deterioration in landscape functioning and character, particularly in cultural landscapes demonstrative of evolving human-environment dynamics that have sustained environmental benefits through time. Cultural and behavioral motives are important root influences to such landscape transitions, yet efforts to address landscape degradation are often hampered by a failure to account for the heterogeneous decision-making nature of its agents of change and the inherent complexity of socio-ecological systems. Novel techniques are required to further disentangle responses to multi-level drivers and discuss alternative landscape development trajectories. Agent-based models constructed by means of participatory approaches present increasingly applied tools in this context. This study sought to capture and model the future perspectives emerging from presently occurring farming discourses in the region of Gera (Lesvos, Greece), characterized by persistent abandonment of its traditionally managed olive plantations. We constructed an agent-based model iteratively in collaboration with the local farming community and experts in landscape research. Empirical findings informed the model through the construction of a farmer typology, revealing a heavy reliance of the farming community upon sectorial profitability, prevalent cultural farming motives and emerging landscape initiatives. The model examined the de-coupled role of agricultural profitability and landscapes initiatives in shaping the behavior of land managers, mapping alternative landscape futures over a period of 25 years. Model results illustrate both increased profitability and action by landscape initiatives are required to reverse abandonment trends within the simulated time frame. The hypothesized ability of landscape initiatives to maintain and promote a cultural drive amongst adhering farmers is crucial for securing behavioral transformations towards professionalism. This study confirmed agent-based modelling to be intuitively received by stakeholders who significantly contributed to model structure refinement and the rejection of a status quo scenario.  相似文献   

11.
This work provides evidence on the determinants, cost differentiation, and development of short‐term marginal costs of dairy farms in important production regions of the European Union. The empirical study is based on the estimation of multi‐input multi‐output Symmetric Generalized McFadden cost functions using an unbalanced panel data set of the European Farm Accountancy Data Network. The results show considerable regional differences in the impact of the outputs, input prices, and fixed factors on marginal costs. Strong evidence can be found that marginal costs decrease over time and is further underlined by the development of derived regional aggregated short‐term supply curves. Marginal cost elasticities and correlation coefficients validate the hypotheses that a high degree of farm specialization, large milk output, and low milk prices are associated with lower marginal costs. Furthermore, the marginal cost spread in the data sample is analyzed. We show that milk output, milk yield, herd size, labor input, and fodder production can be attributed to significant marginal cost differentiation of farms, whereas for crop and animal output, grassland, stock of other animals, and depreciation only minor differentiation can be found.  相似文献   

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