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1.
J Environ Manage ; 308: 114576, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35101805

RESUMO

We examine Adaptive Multi-Paddock (AMP) grazed with short grazing events and planned recovery periods and paired ranches using Conventional Continuous Grazing (CG) at low stock density on vegetation, water infiltration, and soil carbon across SE USA. Increased vegetation standing biomass and plant species dominance-diversity were measured in AMP grazed ranches. Invasive perennial plant species richness and abundance increased with AMP grazing in the south, while in the north they increased on CG grazed ranches. Percent bare ground was significantly greater in CG at the Alabama and Mississippi sites, no different at the Kentucky and mid-Alabama sites, and greater on AMP at the Tennessee pair. On average, surface water infiltration was higher on AMP than paired CG ranches. Averaged over all locations, soil organic carbon stocks to a depth of 1 m were over 13% greater on AMP than CG ranches, and standing crop biomass was >300% higher on AMP ranches. AMP grazing supported substantially higher livestock stocking levels while providing significant improvements in vegetation, soil carbon, and water infiltration functions. AMP grazing also significantly increased available forage nutrition for key constituents, and increased soil carbon to provide significant resource and economic benefits for improving ecological health, resilience, and durability of the family ranch.


Assuntos
Carbono , Solo , Biomassa , Ecossistema , Água
2.
J Environ Manage ; 288: 112409, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33827025

RESUMO

Grassland soils are a large reservoir of soil carbon (C) at risk of loss due to overgrazing in conventional grazing systems. By promoting regenerative grazing management practices that aim to increase soil C storage and soil health, grasslands have the potential to help alleviate rising atmospheric CO2 as well as sustain grass productivity across a vast area of land. Previous research has shown that rotational grazing, specifically adaptive multi-paddock (AMP) grazing that utilizes short-duration rotational grazing at high stocking densities, can increase soil C stocks in grassland ecosystems, but the extent and mechanisms are unknown. We conducted a large-scale on-farm study on five "across the fence" pairs of AMP and conventional grazing (CG) grasslands covering a spectrum of southeast United States grazing lands. We quantified soil C and nitrogen (N) stocks, their isotopic and Fourier-transform infrared spectroscopy signatures as well as their distribution among soil organic matter (SOM) physical fractions characterized by contrasting mechanisms of formation and persistence in soils. Our findings show that the AMP grazing sites had on average 13% (i.e., 9 Mg C ha-1) more soil C and 9% (i.e., 1 Mg N ha-1) more soil N compared to the CG sites over a 1 m depth. Additionally, the stocks' difference was mostly in the mineral-associated organic matter fraction in the A-horizon, suggesting long-term persistence of soil C in AMP grazing farms. The higher N stocks and lower 15N abundance of AMP soils also point to higher N retention in these systems. These findings provide evidence that AMP grazing is a management strategy to sequester C in the soil and retain N in the system, thus contributing to climate change mitigation.


Assuntos
Carbono , Solo , Carbono/análise , Ecossistema , Pradaria , Minerais , Nitrogênio/análise , Sudeste dos Estados Unidos
4.
Politics Life Sci ; 38(2): 117-131, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-32412203

RESUMO

This article proposes equating policies as species to develop a better understanding of how policies emerge, change, and diffuse across policymaking environments. Scholars have long shown an interest in understanding policy change and reinvention, whether incremental or nonincremental. The two subfields of public policy that can answer how and why policies change are not unified, leading to difficulty in comprehensively assessing policy emergence and change. The policy species concept bridges knowledge of the policy process and knowledge in the policy process by creating an operationalized definition of public policy and suggesting a process for classifying policies to observe subsequent behavior. Drawing from the field of biology, the policy species framework outlines how policies possess genotypes and phenotypes, which dictate what a policy is and how it can change. In tracing genotypic and phenetic change over time, policy evolution and change is more easily discernible. In turn, a more precise picture of how policies function is painted.


Assuntos
Evolução Biológica , Formulação de Políticas , Política , Política Pública , Ecossistema , Genótipo , Humanos , Fatores de Tempo
5.
Environ Manage ; 51(5): 969-87, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23525576

RESUMO

Previous research on voluntary environmental programs (VEPs) frequently assesses the effectiveness of federal, state, and third party programs and why organizations seek to join such programs. Yet, research has yet to evaluate the effectiveness or firm motivation relative to local VEPs. Recognizing this gap, our paper examines the structure and organization of Fort Collins' Climate Wise program, a local VEP. Using a variety of sources, we find that the program has successfully met both short- and long-term goals by persistently self-evaluating and seeking outside financial support. Findings from this analysis can aid in understanding and developing local VEPs elsewhere. Specifically, this initial research suggests that local VEPs need to consider local context and available resources when implementing such programs. Furthermore, it is possible for local VEPs to attract a diverse variety of participating firms by avoiding one-size-fits-all participation levels and by establishing a sense of ownership among partners.


Assuntos
Meio Ambiente , Programas Voluntários , Poluição do Ar/prevenção & controle , Colorado , Efeito Estufa/prevenção & controle , Humanos , Governo Local , Avaliação de Programas e Projetos de Saúde
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