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391.
In Western Europe, the change from the Middle Miocene forest-adapted mammalian faunas to the more open woodland faunas of the later Neogene, took place through an abrupt critical period known as the Vallesian Crisis. The Vallesian Crisis involved the disappearance of most of the forest-adapted elements characterizing the middle Miocene, such as tapirs, rhinoceroses, wet-adapted artiodactyls, hominoids, rodents, and the large carnivores of the families Nimravidae and Amphicyonidae. Detailed analysis in the well-calibrated and mostly complete sequence of the type area of the Vallesian Mammal stage, the Vallès-Penedès Basin (NE Spain), reveals that entries were always above the level of exits during the early Vallesian, reaching a diversity maximum at the end of this time. At 9.75 Ma, the Vallesian Crisis involved a sudden decrease of diversity, caused by high extinction levels, well above the number of entries. This event can be correlated with Mi7, a minor isotopic shift at about 9.6 Ma. The correlation of the Vallesian Crisis with such a minor isotopic shift is in contrast with previous, more significant isotopic shifts which had little ecological effects on the terrestrial ecosystems. This inconsistency between the global climate change inferred from the oceanic record and its effect on the structure of the late Miocene terrestrial ecosystems calls for some caution when inferring direct, linear relationships between climate change and mammalian turnover. In contrast with the Plio-Pleistocene glacial-interglacial dynamics, the effects of this climate forcing seem to have been more complex during Miocene times. An alternative pattern of change can be envisaged by proposing a “House of Cards” effect for the Vallesian Crisis. Increasing diversity levels after a prolonged period of stability enhanced terrestrial ecosystems to evolve into a self-organized critical state, which suddenly dropped after a critical threshold was surpassed. In contrast to other critical periods, the final decline of the Vallesian chronofauna was more dependent on the critical state of the system than on the magnitude of the agent which induced the crisis. 相似文献
392.
Jordi Sánchez-Ribas Joseli Oliveira-Ferreira Maria Goreti Rosa-Freitas Lluís Trilla Teresa Fernandes Silva-do-Nascimento 《Memórias do Instituto Oswaldo Cruz》2015,110(6):760-770
Here we present the first in a series of articles about the ecology of immature
stages of anophelines in the Brazilian Yanomami area. We propose a new larval habitat
classification and a new larval sampling methodology. We also report some preliminary
results illustrating the applicability of the methodology based on data collected in
the Brazilian Amazon rainforest in a longitudinal study of two remote Yanomami
communities, Parafuri and Toototobi. In these areas, we mapped and classified 112
natural breeding habitats located in low-order river systems based on their
association with river flood pulses, seasonality and exposure to sun. Our
classification rendered seven types of larval habitats: lakes associated with the
river, which are subdivided into oxbow lakes and nonoxbow lakes, flooded areas
associated with the river, flooded areas not associated with the river, rainfall
pools, small forest streams, medium forest streams and rivers. The methodology for
larval sampling was based on the accurate quantification of the effective breeding
area, taking into account the area of the perimeter and subtypes of microenvironments
present per larval habitat type using a laser range finder and a small portable
inflatable boat. The new classification and new sampling methodology proposed herein
may be useful in vector control programs. 相似文献
393.
María Triviño Alejandra Morán-Ordoñez Kyle Eyvindson Clemens Blattert Daniel Burgas Anna Repo Tähti Pohjanmies Lluís Brotons Tord Snäll Mikko Mönkkönen 《Global Change Biology》2023,29(6):1484-1500
Forests provide a wide variety of ecosystem services (ES) to society. The boreal biome is experiencing the highest rates of warming on the planet and increasing demand for forest products. To foresee how to maximize the adaptation of boreal forests to future warmer conditions and growing demands of forest products, we need a better understanding of the relative importance of forest management and climate change on the supply of ecosystem services. Here, using Finland as a boreal forest case study, we assessed the potential supply of a wide range of ES (timber, bilberry, cowberry, mushrooms, carbon storage, scenic beauty, species habitat availability and deadwood) given seven management regimes and four climate change scenarios. We used the forest simulator SIMO to project forest dynamics for 100 years into the future (2016–2116) and estimate the potential supply of each service using published models. Then, we tested the relative importance of management and climate change as drivers of the future supply of these services using generalized linear mixed models. Our results show that the effects of management on the future supply of these ES were, on average, 11 times higher than the effects of climate change across all services, but greatly differed among them (from 0.53 to 24 times higher for timber and cowberry, respectively). Notably, the importance of these drivers substantially differed among biogeographical zones within the boreal biome. The effects of climate change were 1.6 times higher in northern Finland than in southern Finland, whereas the effects of management were the opposite—they were three times higher in the south compared to the north. We conclude that new guidelines for adapting forests to global change should account for regional differences and the variation in the effects of climate change and management on different forest ES. 相似文献
394.
Duane Andrea Kelly Luke Giljohann Kate Batllori Enric McCarthy Michael Brotons Lluís 《Ecosystems》2019,22(6):1338-1351
Ecosystems - Understanding the interplay between climate, fuel and fire is necessary for developing strategies that minimize the negative impacts of fire on people and ecosystems. Here, we aim to... 相似文献
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Llu��s Corominas G��rkan Sin Sebasti�� Puig Maria Dolors Balaguer Peter A. Vanrolleghem Jes��s Colprim 《Bioprocess and biosystems engineering》2011,34(2):205-214
The purpose of this paper is to refine the BIOMATH calibration protocol for SBR systems, in particular to develop a pragmatic
calibration protocol that takes advantage of SBR information-rich data, defines a simulation strategy to obtain proper initial
conditions for model calibration and provides statistical evaluation of the calibration outcome. The updated calibration protocol
is then evaluated on a case study to obtain a thoroughly validated model for testing the flexibility of an N-removing SBR
to adapt the operating conditions to the changing influent wastewater load. The performance of reference operation using fixed
phase length and dissolved oxygen set points and two real-time control strategies is compared to find optimal operation under
dynamic conditions. The results show that a validated model of high quality is obtained using the updated protocol and that
the optimization of the system’s performance can be achieved in different manners by implementing the proposed control strategies. 相似文献