Conviction seeking efficacy: Sustainable agriculture and the politics of co-optation

Proponents of sustainable agriculture seek deeply rooted social changes, but to advance this agenda requires political credibility and work with diverse partners. Asthe literature on political co-optation makesclear, the tension between conviction andcredibility is persistent and unavoidable; nota problem to be solved so much as a built-incondition of movement politics. Drawing on acase history of California's largestsustainable agriculture organization, astructural assessment is made of the strategicchoices facing movement leaders, organizationaltensions that accompany these choices, andperceived gains and losses. The case historydemonstrates how movement leaders craft middlerange strategies that adapt to politicalcircumstances while retaining attachments tocore values and constituencies. Thesestrategies are ripe with tradeoffs, placingdemands on leaders who must implement them in aspirit that sustains organizational vitalitywhile broadening political and social impact.But they also enlarge the democraticsensibilities of movement leaders, increasingtheir ability to listen, learn, and forgealliances based on shared goals rather thansimilar motives.     

麻疯树构件的生殖配置研究

本文首次在木本植物构件层次上探讨了生殖配置的大小依赖性与权衡问题。据测定,麻疯树果期生殖构件生殖部分的绝对配置为7g,相对配置为23％,分别变动于2．088g-22．05g和7％～49％之间。据回归,生殖构件的营养和生殖部分相对配置为直线负相关,为权衡关系。以构件生物量为大小指标,与麻疯树生殖的绝对配置符合开口向下的抛物线模型,而与生殖的相对配置之间关系符合开口向上的幂函数模型。麻疯树生殖构件两类生殖配置的大小依赖性的曲线模式不同,在不同样地、不同层次都存在普遍性和一致性。构件水平上生殖的相对配置与绝对配置关系模型变化趋势相反,与个体生殖的绝对和相对配置不同。在生产上,需要把优化生殖构件大小,人为修枝,提高当年生殖产量。     

Quantifying economic and environmental tradeoffs of walnut arthropod pest management

Many arthropod pesticides used by California walnut growers have been linked to water quality impairment. However lower risk alternatives are often associated with higher costs. The purpose of this paper was to: (1) identify currently practiced pest management strategies with probable high water quality impact, (2) quantify the importance of factors which affect economic tradeoffs associated with reducing water quality impact, and (3) identify pest management strategies that could potentially lower water quality impact with less economic consequence. An integrated analysis using environmental, economic and pesticide use data revealed that 96% of the pest management strategies analyzed were candidates for reducing the impact on water quality. Replacement of current pesticides by alternative pest controls lowered probable impact, but resulted in an economic tradeoff in the form of higher costs for the majority of growers. If biological control could eliminate the need for miticides and aphicides, this tradeoff could be replaced by savings for nearly half of the sample analyzed. This cost savings would most likely be realized by growers who currently have low numbers of pests that are not candidates for biological control, and relatively high use of organophosphates and miticides. The results indicated that if these pest management strategies had been replaced by alternative strategies and biological control, then total organophosphate, pyrethroid, and miticide active ingredient use would have been reduced by an average of 5 kg/hectare per year, while simultaneously lowering the grower’s pest management costs by an average of $128/hectare, thus contributing to both economic and environmental long-run sustainability.     

False idolatry of the mythical growth versus immunity tradeoff in molecular systems plant pathology

Systems studies of signal transduction pathways that modulate plant growth and immunity are rapidly identifying a large number of interactions within these pathways. These interactions are frequently presented as mechanisms allowing a plant to make proper decisions with regards to how to partition energy and resources in a proposed growth versus immunity tradeoff. This is a reinterpretation of the classical costs of resistance theory that has a long history in the ecology research community. While the ecology community is reinterpreting this theory, the reinterpretation has not been introduced into the molecular systems biology community that is studying the intersection of regulatory pathways. In this article, I describe evidence against a simple growth versus immunity tradeoff concept and propose an alternative wherein the intersection of these regulatory pathways is instead designed to coordinate these pathways, and not simply link them in mutual antagonism, to optimize fitness in complex environments where resistance/immunity and growth do not have simple linear relationships with fitness.     

Sustainable management of urban tree stocks based on multi-criteria scenario modelling

Urban tree managers are challenged with sustainable ecosystem service provision in particular when urban tree populations become over mature. Therefore, managers have to quantify both future services and population stability. We exemplify an approach for estimating the tradeoff between cooling, CO₂-fixation and crown volume development, and the time until the changing tree population becomes stable. Using a realistic distribution of age classes and functional groups, we evaluate the balance between service provision and stabilization over decades to centuries. Their tradeoff mainly depends on the proportion of functional groups used in the replacement of mortal trees. Moreover, managers may steer tradeoff through an intentional planting postponement and acquisition of additional space.     

Interactions between soil conservation and dryland farming of heterogeneously eroding areas in Loess Hills,China

The unidirectional impacts of soil conservation on dryland farming and local livelihood have been well studied. However, there are gaps in literature regarding the interactions among factors, such as labor force and financial capital, in response to soil conservation, as well as the influence of such interactions on the relationships between environmental projects and agricultural development. By combining the Chinese Soil Loss Equation (CSLE) model and statistical analyses, this study investigated the spatio-temporal characteristics of soil erosion while also identifying the controlling factors that affect crop and livestock farming. The aim was to reveal how these factors interacted to influence agriculture in two case study areas between 2000 and 2017. The results showed that soil erosion substantially declined as a consequence of soil conservation, while the output from crop farming increased, indicating that there was a synergy between soil conservation and dryland farming in both the districts, over time; and factors facilitating crop farming, such as labor force, agricultural machinery, and irrigation, appeared to exert an adverse effect on livestock farming in both areas, implying a tradeoff between livestock and crop farming in the context of programs such as the Grain for Green Program (GGP) in the Loess Hills. Such a tradeoff is a result of the competition for cropland and labor that exists due to grazing prohibition and rural-urban migration. Therefore, policy-related resolutions are required to address the land use conflicts and migration-related rural labor losing due to implementation of the GGP in the Loess Hills.