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71.
72.
Marina Mazn Nikolay Aguirre Cristian Echeverría James Aronson 《Restoration Ecology》2019,27(5):992-999
Ecological restoration is becoming mainstreamed worldwide but target ecosystems' responses to restorative interventions are not sufficiently monitored, in terms of the wide range of ecological, social, and economic attributes available. In order to highlight and better understand this problem, we conducted a literature review of the ecological, social, and economic attributes cited in the scientific literature used for monitoring the success of ecological restoration projects in Latin America and the Caribbean region, where no regional study of this kind has previously been conducted. In 84 of the 91 articles retained for the study, ecological indicators were evaluated, while only seven articles included measurements of socioeconomic indicators. Regarding the Society for Ecological Restoration Primer attributes of restored ecosystems, we only found indicators measuring attributes 1–6, with attribute 1 (species assemblages) predominating (73%), followed by physical conditions (54%) and ecological functions (51%). Brazil was the country in the region where most monitoring was being carried out (51% of the articles), and tropical rainforest (33%) and tropical dry forest (25%) were the ecosystem types where ecological restoration was most frequently monitored. Highly vulnerable ecosystems such as mangroves and paramos were underrepresented. Attributes related to ecosystem stability or to governance and education of communities were not monitored at all. More real long‐term monitoring, instead of chronosequences, is needed, especially where understanding socioeconomic implications of, and barriers to, effective ecological restoration is a top priority. 相似文献
73.
Seth M. Rudman Jared M. Goos Joseph B. Burant Kevin V. Brix Taylor C. Gibbons Colin J. Brauner Punidan D. Jeyasingh 《Ecology letters》2019,22(4):645-653
Evidence that organisms evolve rapidly enough to alter ecological dynamics necessitates investigation of the reciprocal links between ecology and evolution. Data that link genotype to phenotype to ecology are needed to understand both the process and ecological consequences of rapid evolution. Here, we quantified the suite of elements in individuals (i.e., ionome) and differences in the fluxes of key nutrients across populations of threespine stickleback. We find that allelic variation associated with freshwater adaptation that controls bony plating is associated with changes in the ionome and nutrient recycling. More broadly, we find that adaptation of marine stickleback to freshwater conditions shifts the ionomes of natural populations and populations raised in common gardens. In both cases ionomic divergence between populations was primarily driven by differences in trace elements rather than elements typically associated with bone. These findings demonstrate the utility of ecological stoichiometry and the importance of ionome‐wide data in understanding eco‐evolutionary dynamics. 相似文献
74.
An early investigation at the Biosphere-2 Laboratory, an artificial ecosystem in the Arizona desert, had shown that the flavonoid content of cacti grown in glass-filtered solar light was lower than of cacti grown in normal solar light. This was attributed to the absence of ultraviolet (UV) radiation, which is required for flavonoid biosynthesis. In this study, two species of Opuntia cacti were grown in solar and UV-depleted light, and their flavonol contents of different tissues were determined by HPLC. O. wilcoxii, previously raised in the absence of UV light, was exposed to normal solar light. The flavonol content of young O. wilcoxii pads was 28-fold higher when grown in solar light as compared to UV-depleted light. The flavonol contents of mature outer tissues were only slightly higher. O. violacea, previously raised in solar light, was also maintained in the same UV-depleted artificial ecosystem. The flavonol content after hydrolysis of outer tissues was similar, whether grown in solar light or UV-depleted light. We attribute these responses to different biosynthetic and metabolic rates of young vs. mature plant tissues; slow-growing mature tissues neither produce nor metabolize compounds as quickly as immature tissues. These findings indicate that artificial ecosystems can influence the production of natural products in cultivated plants. 相似文献
75.
《International journal for parasitology》2019,49(1):49-61
Ocean warming and acidification are general consequences of rising atmospheric CO2 concentrations. In addition to future predictions, highly productive systems such as the Humboldt Current System are characterized by important variations in both temperature and pCO2 level, but how these physical–chemical ocean changes might influence the transmission and survival of parasites has not been assessed. This study experimentally evaluated the effects of temperature (14, 18 and 25 °C) and the combined effects of temperature (∼15 and 20 °C) and pCO2 level (∼500 and 1400 microatmospheres (µatm) on the emergence and survival of two species of marine trematodes—Echinostomatidae gen. sp. and Philophthalmidae gen. sp.—both of which infect the intertidal snail Echinolittorina peruviana. Snails were collected from intertidal rocky pools in a year-round upwelling area of the northern Humboldt Current System (23°S). Two experiments assessed parasite emergence and survival by simulating emersion-immersion tidal cycles. To assess parasite survival, 2 h old cercariae (on average) were taken from a pool of infected snails incubated at 20–25 °C, and their mortality was recorded every 6 h until all the cercariae were dead. For both species, a trade-off between high emergence and low survival of cercariae was observed in the high temperature treatment. Species-specific responses to the combination of temperature and pCO2 levels were also observed: the emergence of Echinostomatidae cercariae was highest at 20 °C regardless of the pCO2 levels. By contrast, the emergence of Philophthalmidae cercariae was highest at elevated pCO2 (15 and 20 °C), suggesting that CO2 may react synergistically with temperature, increasing transmission success of this parasite in coastal ecosystems of the Humboldt Current System where water temperature and pH are expected to decrease. In conclusion, our results suggest that integrating temperature-pCO2 interactions in parasite studies is essential for understanding the consequence of climate change in future marine ecosystem health. 相似文献
76.
Removal of apex predators can drive ecological regime shifts owing to compensatory positive and negative population level responses by organisms at lower trophic levels. Despite evidence that apex predators can influence ecosystems though multiple ecological pathways, most studies investigating apex predators’ effects on ecosystems have considered just one pathway in isolation. Here, we provide evidence that lethal control of an apex predator, the dingo Canis dingo, drives shifts in the structure of Australia's tropical‐savannah ecosystems. We compared mammal assemblages and understorey structure at seven paired‐sites. Each site comprised an area where people poisoned dingoes and an area without dingo control. The effects of dingo control on mammals scaled with body size. Where dingoes were poisoned, we found greater activity of herbivorous macropods and feral cats, a mesopredator, but sparser understorey vegetation and lower abundances of native rodents. Our study suggests that ecological cascades arising from apex predators’ suppressive effects on herbivores and mesopredators occur simultaneously. Concordant effects of dingo removal across tropical‐savannah, forest and desert biomes suggest that dingoes once exerted ubiquitous top–down effects across Australia and provides support for calls that top–down forcing should be considered a fundamental process governing ecosystem structure. 相似文献
77.
Joshua S. Lynn Melanie R. Kazenel Stephanie N. Kivlin Jennifer A. Rudgers 《Ecography》2019,42(9):1600-1612
Many biotic interactions influence community structure, yet most distribution models for plants have focused on plant competition or used only abiotic variables to predict plant abundance. Furthermore, biotic interactions are commonly context‐dependent across abiotic gradients. For example, plant–plant interactions can grade from competition to facilitation over temperature gradients. We used a hierarchical Bayesian framework to predict the abundances of 12 plant species across a mountain landscape and test hypotheses on the context‐dependency of biotic interactions over abiotic gradients. We combined field‐based estimates of six biotic interactions (foliar herbivory and pathogen damage, fungal root colonization, fossorial mammal disturbance, plant cover and plant diversity) with abiotic data on climate and soil depth, nutrients and moisture. All biotic interactions were significantly context‐dependent along temperature gradients. Results supported the stress gradient hypothesis: as abiotic stress increased, the strength or direction of the relationship between biotic variables and plant abundance generally switched from negative (suggesting suppressed plant abundance) to positive (suggesting facilitation/mutualism). For half of the species, plant cover was the best predictor of abundance, suggesting that the prior focus on plant–plant interactions is well‐justified. Explicitly incorporating the context‐dependency of biotic interactions generated novel hypotheses about drivers of plant abundance across abiotic gradients and may improve the accuracy of niche models. 相似文献
78.
General circulation models predict increases in temperature and precipitation in the Arctic as the result of increases in atmospheric carbon dioxide concentrations. Arctic ecosystems are strongly constrained by temperature, and may be expected to be markedly influenced by climate change. Perturbation experiments have been used to predict how Arctic ecosystems will respond to global climatic change, but these have often simulated individual perturbations (e.g. temperature alone) and have largely been confined to the short Arctic summer. The importance of interactions between global change variables (e.g. CO2, temperature, precipitation) has rarely been examined, and much experimentation has been short-term. Similarly, very little experimentation has occurred in the winter when General circulation models predict the largest changes in climate will take place. Recent studies have clearly demonstrated that Arctic ecosystems are not dormant during the winter and thus much greater emphasis on experimentation during this period is essential to improve our understanding of how these ecosystems will respond to global change. This, combined with more long-term experimentation, direct observation of natural vegetation change (e.g. at the tundra/taiga boundary) and improvements in model predictions is necessary if we are to understand the future nature and extent of Arctic ecosystems in a changing climate. 相似文献
79.
The arbuscular mycorrhizal (AM) status of 67 plant species in a savanna community in the hot, dry valley of Jinsha River, southwest China was surveyed. It was found that about 95% of the plant species formed AM and 5% possibly formed AM. The composition of AM fungi (AMF) in the rhizosphere soils was also investigated. The AMF spore density ranged from 5 to 6,400 per 100 g soil, with an average of 1,530, and these spores/sporocarps were identified as belonging to six genera. Fungi belonging to the genera Glomus and Acaulospora were the dominant AMF. High densities of AMF spores in the rhizosphere soils, and the intensive colonization of the plant roots, indicated that plants grown in this valley-type savanna may be highly dependent on AM. 相似文献
80.
Kentaro?HayashiEmail author Masanori?Okazaki Norihiro?Itsubo Atsushi?Inaba 《The International Journal of Life Cycle Assessment》2004,9(1):13-22
Background Acidification is one of the important impact categories for life cycle impact assessment. Although its characterization has
progressed during this decade through the employment of midpoint approaches, only limited studies of endpoint approaches have
been performed. Objective. This study aimed at developing damage function of acidification for terrestrial ecosystems in Japan.
Damage function expresses a quantitative relationship between the inventory and endpoint damage.
Methods The geographical boundary was limited in Japan both for emission and impact. In this study, sulfur dioxide (SO2), nitrogen monoxide (NO), nitrogen dioxide (NO2) (NO and NO2 collectively mean NOx), hydrogen chloride (HC1), and ammonia (NH3) were considered as major causative substances of acidification. Net primary production (NPP) of existing vegetation was
adopted as an impact indicator of terrestrial ecosystems. The aluminum toxicity was adopted as the major factor of effect
on terrestrial ecosystems due to acidification. The leachate concentration of monomeric inorganic aluminum ions was selected
to express the plant toxicity of aluminum.
Results and Discussion The results of damage function gave utilizable factors both for a midpoint approach and an endpoint approach; Atmospheric
Deposition Factor (ADF) and Damage Factor (DF) applicable to the former and the latter, respectively. The ADF indicates an
increase of H+ deposition per unit area to an additional emission of causative sustance. The additional emission corresponds to some alternatives
in industry, not the baseline emission. The DF indicates the total NPP damage in all of Japan due to the additional emission
of causative substances. The derived NPP damage is on the order of one millionth of the NPP itself. HC1 and NH3 showed larger
ADFs and DFs than that of SO2 and NOx. The reason was ascribed to the relatively large source-receptor relationships (SRR) of HC1 and NH3. However, since the method applied to determine the SRR of HC1 and NH3 has larger uncertainties than that of SO2 and NOx, attention is needed to handle the difference.
Conclusion The damage function easily defines the concrete NPP damage due to an additional emission. The impact indica tor, NPP, also
has an advantage in its mass unit that is directly summable through the entire impact categories. Expansion of endpoints,
such as in aquatic ecosystems, material degradation, human health, and biodiversity aspects of terrestrial ecosystems, is
an important subject for future work. Further, uncertain analyses for major parameters will provide helpful information on
the reliability of damage function. 相似文献