Regional Environmental Change - Understanding drivers of forest-cover change is essential for a broad range of ecosystem properties. In this work, we assessed changes in forest cover using... 相似文献
Agricultural water management needs to evolve in view of increased water scarcity, especially when farming and natural protected areas are closely linked. In the study site of Doñana (southern Spain), water is shared by rice producers and a world heritage biodiversity ecosystem. Our aim is to contribute to defining adaptation strategies that may build resilience to increasing water scarcity and minimize water conflicts among agricultural and natural systems. The analytical framework links a participatory process with quantitative methods to prioritize the adaptation options. Bottom-up proposed adaptation measures are evaluated by a multi-criteria analysis (MCA) that includes both socioeconomic criteria and criteria of the ecosystem services affected by the adaptation options. Criteria weights are estimated by three different methods—analytic hierarchy process, Likert scale and equal weights—that are then compared. Finally, scores from an MCA are input into an optimization model used to determine the optimal land-use distribution in order to maximize utility and land-use diversification according to different scenarios of funds and water availability. While our results show a spectrum of perceptions of priorities among stakeholders, there is one overriding theme that is to define a way to restore part of the rice fields to natural wetlands. These results hold true under the current climate scenario and even more so under an increased water scarcity scenario. 相似文献
European forestry is facing many challenges, including the need to adapt to climate change and an unprecedented increase in forest damage. We investigated these challenges in a Norway spruce-dominated mountain region in Central Europe. We used the model Sibyla to explore forest biomass production to the year 2100 under climate change and under two alternative management systems: the currently applied management (CM), which strives to actively improve the forest’s adaptive capacity, and no management (NM) as a reference. Because biodiversity is thought to have mostly positive effects on the adaptive capacity of forests and on the quality of ecosystem services, we explored how climate change and management affect indicators of biodiversity. We found a differential response across the elevation-climatic gradient, including a drought-induced decrease in biomass production over large areas. With CM, the support of non-spruce species and the projected improvement of their growth increased tree species diversity. The promotion of species with higher survival rates led to a decrease in forest damage relative to both the present conditions and NM. NM preserved the high density of over-matured spruce trees, which caused forest damage to increase. An abundance of dead wood and large standing trees, which can increase biodiversity, increased with NM. Our results suggest that commercial spruce forests, which are not actively adapted to climate change, tend to preserve their monospecific composition at a cost of increased forest damage. The persisting high rates of damage along with the adverse effects of climate change make the prospects of such forests uncertain. 相似文献
Soil-dwelling annelids of the genus Enchytraeus are used in ecotoxicology for testing of chemicals mixed in artificial soil or for testing of wastes and soils of unknown quality. ISO 16387 describes a method for determining the effects of substances or contaminated soils on survival and reproduction of Enchytraeus albidus or of the smaller species Enchytraeus buchholzi or Enchy-traeus crypticus. After the total test duration of 6 (or 4)?weeks, the juveniles hatched in the meantime are counted. There are several possible extraction techniques, which are always followed by counting the juveniles by hand, but none of them seems easy to handle. We proposed a new modification of the worm extraction method using flotation of fixed and stained juveniles followed by taking a photograph. The digital image of the juveniles is evaluated by computer processing. It makes the counting of juveniles much easier and less labor intensive. 相似文献
Remotely sensed imageries were used to analyze the response of desert vegetation to physiographic factors and accumulated precipitation in drier and wetter years within a region of >16,500 km2 sampled with 5,000 random pixels of 30 m. Vegetation development was indexed by the annual maximum values for greenness (SAVI) and canopy water content (NDII). Precipitation was interpolated from the 0.25° grid of the Tropical Rainfall Measurement Mission satellite-based estimates, showing a regional average of ~55 mm in the wetter year. The vegetation indices were only weakly related to total precipitation, often in a negative sense. Terrain factors that most often affected the vegetation indices, in multiple regression models, were Topographic Wetness Index, elevation, and slope gradient; these often had different signs for SAVI and for NDII. Models for NDII on intrusive igneous rocks gave better results than on extrusive igneous rocks. The strongest patterns in vegetation development were the contrast among Pacific coast, Cordillera, and Gulf coast subregions and the generally stronger results for NDII than SAVI. 相似文献
Green algae Cladophora aegagropila, present in cooling water of thermal power plants, causes many problems and complications, especially during summer. However, algae and its metabolites are rarely eliminated by common removal methods. In this work, the elimination efficiency of electrochemically prepared potassium ferrate(VI) on algae from cooling water was investigated. The influence of experimental parameters, such as Fe(VI) dosage, application time, pH of the system, temperature and hydrodynamics of the solution on removal efficiency, was optimized. This study demonstrates that algae C. aegagropila can be effectively removed from cooling water by ferrate. Application of ferrate(VI) at the optimized dosage and under the suitable conditions (temperature, pH) leads to 100% removal of green algae Cladophora from the system. Environmentally friendly reduction products (Fe(III)) and coagulation properties favour the application of ferrate for the treatment of water contaminated with studied microorganisms compared to other methods such as chlorination and use of permanganate, where harmful products are produced.
In general, tourism plays a significant role in the economy of archipelagos and islands. The Autonomous Region of the Azores has a great potential for tourism, offering multiple attractions, both natural and cultural, creating a big challenge for a sustainable tourism policy since little attention has been paid to the archipelagos and their special needs. This work aims to understand the profile and type of ecotourist that visits the Azores. This knowledge is of great importance for a better management and development of nature-based tourism, and products tailored to the needs and expectations of visitors. The data were collected by means of exit surveys conducted at the Airport of São Miguel Island, the larger and most populated island of the archipelago, during the high tourist season—July–September 2009. The analysis of the visitor’s profile and preferences is crucial to draw adequate strategies of management for tourism, while it helps to adequate the offer to the demand. Results showed that 41.1 % of the tourists claimed to be attracted to the islands due to their “natural values” (e.g., landscape, biodiversity, and geodiversity). The most practiced activities were whale-watching (32.4 %) and mountaineering/hiking (31.6 %), followed by diving (7 %) and other sports (5.1 %). The tourists’ profile points to a mainstream, soft, and incidental type of ecotourist. This information helps to develop and support a strategic planning and management, both at local and regional levels, for sustainable tourism policies. 相似文献
Research on the influence of biosurfactants on the efficiency of in situ bioremediation of contaminated soil is continuously growing. Despite the constant progress in understanding the mechanisms involved in the effects of biosurfactants, there are still many factors that are not sufficiently elucidated. There is a lack of research on autochthonous or exogenous microbial metabolism when biostimulation or bioaugmentation is carried out to produce biosurfactants at contaminated sites. In addition, studies on the application of techniques that measure the biosurfactants produced in situ are needed. This is important because, although the positive influence of biosurfactants is often reported, there are also studies where no effect or negative effects have been observed. This review aimed to examine some studies on factors that can improve the production of biosurfactants in soils during in situ bioremediation. Moreover, this work reviews the methodologies that can be used for measuring the production of these biocomposts. We reviewed studies on the potential of biosurfactants to improve the bioremediation of hydrocarbons, as well as the limitations of methods for the production of these biomolecules by microorganisms in soil. 相似文献
The use of recurrence plots have been extensively used in various fields. In this work, recurrence plots investigate the changes in the non-linear behaviour of urban air pollution using large datasets of raw data (hourly). This analysis has not been used before to extract information from large datasets for this type of non-linear problem. Two different approaches have been used to tackle this problem. The first approach is to show results according to monitoring network. The second approach is to show the results by particle type. This analysis shows the feasibility of using recurrence analysis for pollution monitoring and control. 相似文献
The accumulation of heavy metals in the environment may have a wide range of health effects on animals and humans. Thus, in this study, the concentrations of arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg) in the blood and tissues (liver and kidney) of Portuguese common buzzards (Buteo buteo) were determined by inductively coupled plasma-mass spectrometer (ICP-MS) in order to monitor environmental pollution to these elements. In general, Hg and As were the elements which appeared in the highest and lowest concentrations, respectively. A highest percentage of non-detected concentration was found for blood Cd (94.6 %) but, in turn, it was the only metal that was detected in all kidney samples. The kidney was the analyzed sample which showed the highest concentrations of each element evaluated. Statistically, significant differences among blood, liver, and kidney samples were observed for As and Cd (P?0.05). Cd concentrations in kidney and liver varied significantly with age: Adults showed higher hepatic and renal Cd concentrations than juveniles. Blood Pb concentration seems to show an association with the hunting season. Although raptors are at the top of the food chain and are thus potentially exposed to any biomagnification processes that may occur in a food web, the individuals evaluated in this study generally had low levels of heavy metals in blood and tissues. However, chronic exposure to these metals was verified. The results presented here lend weight to arguments in favor of continuous biomonitoring of metals and metalloids, since heavy metals may accumulate to levels that will pose a risk to both human health and the environment. 相似文献