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1.
Sci Total Environ ; 747: 141112, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-32791405

RESUMO

How anticipated climate change might affect long-term outcomes of present-day agricultural conservation practices remains a key uncertainty that could benefit water quality and biodiversity conservation planning. To explore this issue, we forecasted how the stream fish communities in the Western Lake Erie Basin (WLEB) would respond to increasing amounts of agricultural conservation practice (ACP) implementation under two IPCC future greenhouse gas emission scenarios (RCP4.5: moderate reductions; RCP8.5: business-as-usual conditions) during 2020-2065. We used output from 19 General Circulation Models to drive linked agricultural land use (APEX), watershed hydrology (SWAT), and stream fish distribution (boosted regression tree) models, subsequently analyzing how projected changes in habitat would influence fish community composition and functional trait diversity. Our models predicted both positive and negative effects of climate change and ACP implementation on WLEB stream fishes. For most species, climate and ACPs influenced species in the same direction, with climate effects outweighing those of ACP implementation. Functional trait analysis helped clarify the varied responses among species, indicating that more extreme climate change would reduce available habitat for large-bodied, cool-water species with equilibrium life-histories, many of which also are of importance to recreational fishing (e.g., northern pike, smallmouth bass). By contrast, available habitat for warm-water, benthic species with more periodic or opportunistic life-histories (e.g., northern hogsucker, greater redhorse, greenside darter) was predicted to increase. Further, ACP implementation was projected to hasten these shifts, suggesting that efforts to improve water quality could come with costs to other ecosystem services (e.g., recreational fishing opportunities). Collectively, our findings demonstrate the need to consider biological outcomes when developing strategies to mitigate water quality impairment and highlight the value of physical-biological modeling approaches to agricultural and biological conservation planning in a changing climate.


Assuntos
Ecossistema , Rios , Agricultura , Animais , Mudança Climática , Conservação dos Recursos Naturais , Hidrologia
2.
Sci Total Environ ; 711: 135133, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31837878

RESUMO

Designed ecosystems are built as part of ongoing urban expansion, providing a suite of valued ecosystem services. However, these new ecosystems could also promote disservices by facilitating the colonization and spread of invasive species. We conduct the first assessment of the quantity and invasion of an overlooked designed ecosystem: stormwater ponds. These ponds are commonly recommended for managing urban hydrology, but little is known about their ecology or extent of proliferation. Using a broad-scale survey of pond coverage in Florida, USA, we found that over 76,000 stormwater ponds have been built just in this state, forming 2.7% of total urban land cover. This extensive pondscape of manufactured habitats could facilitate species spread throughout urban areas and into nearby natural waterbodies. We also conducted a survey of the severity of plant invasion in 30 ponds in Gainesville, FL, US across two pond types (dry vs. wet), and a gradient of management intensities (low, medium, high) and pond ages. We unexpectedly found a high number of invasive plant species (28 in just 30 ponds). Ninety-six percent of surveyed ponds contained from one to ten of these species, with ponds exhibiting high turnover in invader composition (i.e., high beta diversity). The bank sections of dry unmanaged ponds exhibited the highest mean invasive species richness (5.8 ± 1.3) and the inundated centers of wet medium managed ponds exhibited the highest mean invasive species cover (34 ± 12%). Invasive plant richness and cover also tended to be greater in dry ponds with higher soil nutrient levels, and in older wet ponds. Therefore, we found that highly maintained and younger wet ponds were the least invaded. Nevertheless, common management practices that limit plant invasions may also limit native species establishment and invasion may increase in the decades following pond construction.


Assuntos
Ecossistema , Tanques , Florida , Plantas
3.
Sch Psychol Q ; 34(1): 86-95, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29911877

RESUMO

Research has supported the applied use of Direct Behavior Rating Single-Item Scale (DBR-SIS) targets of "academic engagement" and "disruptive behavior" for a range of purposes, including universal screening and progress monitoring. Though useful in evaluating social behavior and externalizing problems, these targets have limited utility in evaluating emotional behavior and internalizing problems. Thus, the primary purpose of this study was to support the initial development and validation of a novel DBR-SIS target of "unhappy," which was intended to tap into the specific construct of depression. A particular focus of this study was on the novel target's utility within universal screening. A secondary purpose was to further validate the aforementioned existing DBR-SIS targets. Within this study, 87 teachers rated 1,227 students across two measures (i.e., DBR-SIS and the Teacher Observation of Classroom Adaptation-Checklist [TOCA-C]) and time points (i.e., fall and spring). Correlational analyses supported the test-retest reliability of each DBR-SIS target, as well as its convergent and discriminant validity across concurrent and predictive comparisons. Receiver operating characteristic (ROC) curve analyses further supported (a) the overall diagnostic accuracy of each target (as indicated by the area under the curve [AUC] statistic), as well as (b) the selection of cut scores found to accurately differentiate at-risk and not at-risk students (as indicated by conditional probability statistics). A broader review of findings suggested that across the majority of analyses, the existing DBR-SIS targets outperformed the novel "unhappy" target. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Comportamento Infantil/psicologia , Depressão/diagnóstico , Transtorno Depressivo/diagnóstico , Adolescente , Escala de Avaliação Comportamental , Criança , Depressão/psicologia , Transtorno Depressivo/psicologia , Emoções , Feminino , Humanos , Masculino , Programas de Rastreamento , Reprodutibilidade dos Testes , Estudantes/psicologia
4.
Oecologia ; 184(2): 441-452, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28477047

RESUMO

Colonist quantity, quality, and arrival frequency can all individually drive the dynamics and extinction of new populations. However, we do not understand which has the strongest influence, nor the circumstances under which their relative importance may change. We conducted a field mesocosm experiment that manipulated colonist quantity, quality, and arrival frequency in two zooplankton species (Daphnia pulicaria and Skistodiaptomus oregonensis). Individuals of each species were cultured under either high or low food concentrations to produce, respectively, 'good' and 'poor' quality colonists. Each species was then introduced at either small (2 individuals) or large introduction quantities (8 individuals) divided over single or multiple introduction events. We found that the extinction of Daphnia pulicaria was not particularly affected by any of our treatments. Introductions of just two individuals performed as well as larger or more frequent introductions, regardless of quality. Conversely, Skistodiaptomus oregonensis extinction was strongly driven by arrival frequency. Populations that arrived in a single event exhibited high rates of extinction (75-83%), with this probability declining dramatically when colonists were introduced over multiple events (33% extinction). Our results show that other less studied aspects of the colonist pool, such as arrival frequency, could be as important to population persistence as the initial quantity of arriving colonists. Additionally, there are potentially numerous species that are well suited to succeeding with a small number of founders, and whose success is therefore not necessarily dependent upon colonist quantity, quality, or arrival frequency.


Assuntos
Extinção Biológica , Zooplâncton , Animais , Daphnia , Dinâmica Populacional
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