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• Current management may not sustain oaks while restraining maples in public forests. • Alternative management can help sustain oaks in public forests. • Silvicultural management on public lands has limited regional effects. • The relative contributions of NF and SF at the regional scale are not consistent. Active management for promoting oaks (Quercus spp.) and restraining maples (Acer spp.) is mostly conducted in public forests (e.g., national forests [NF] and state forests [SF]) because of oaks' ecological and economic importance. Studies have shown that current management efforts have limited success, meanwhile, oak-dominant forests continue to shift in composition and structure to shade-tolerant, fire-sensitive mesophytic species (e.g., red maple A. rubrum). It remains to be evaluated whether current management can achieve its objectives in public forests and at regional scales. In this study, we investigated the long-term outcomes of business-as-usual (BAU) and alternative management (AltMgt) scenarios in a large, temperate hardwood forest landscape in southern Ohio, US. The BAU approach simulates contemporary management, informed by harvest records across public lands and a geospatial disturbance database (i.e., LANDFIRE) to infer private land management. Whereas the AltMgt scenario increases the pace and scale of forest management on public lands through two-stage oak shelterwood harvests, treated every ten years across 10% of the land area with private land remaining as BAU. We used a spatially explicit and dynamic forest landscape model to project species compositional and structural changes under these two scenarios. Our results demonstrate that BAU management in public forests may not successfully sustain oak but instead favors the colonization of maples. Further, management objectives to promote oaks could be achieved on public forests under the AltMgt scenario, but such alternative management had limited impacts at the regional scale when including private lands. The management of NF and SF has a crucial role in driving regional changes in oak and maple abundance, particularly when private lands continued their BAU management. Starting conditions by landownership are also important considerations for oak-maple dynamics through time, implying the need to have a range of priorities and objectives, under different time frames, when developing long-term conservation plans for oak forests at regional-scales. [ABSTRACT FROM AUTHOR]

Since the negative trends in bird populations breeding in intensified farming systems of western Europe could be difficult to reverse, this article highlights the importance of also considering conservation measures in key-sites for grassland birds in European Russia where farming abandonment is the prevailing threat. Non-passerine bird species frequency was studied in the period 2007–2009, within 193 count points in diversely managed meadows of 36 key-regions in Russia and compared to the outcomes of 492 count points in hay meadows of 25 key-regions in France. In Russia, five species were recorded in at least 35% of the plots, among which the Corncrake Crex crex in 75% of total sample. Pair density was defined in two hay meadow systems in Russia with the Territory Mapping method. Bird biomass density was not different when compared to the most favourable conditions recorded in France, but with a Corncrake density of 2.1 calling males per 10 ha vs. 1.0 in the major French stronghold. Experimental results of alternative management showed the limits of mowing postponement programmes in French grassland ecosystems and enabled us to explore the effects of rotational mowing for limiting habitat loss due to farming abandonment in Russia. [ABSTRACT FROM AUTHOR]

Attract-and-kill is a possible alternative to the conventional control of Mediterranean fruit fly (medfly), Ceratitis capitata Wiedemann (Diptera: Tephritidae) with bait or cover sprays of organophosphate insecticides. In this study, we determined if an attract-and-kill device (MagMED ® ) could be applied alone at the recommended rate (80 devices/ha), or needed to be combined with other conventional control tactics to suppress medfly in deciduous fruit orchards (apple, nectarine, peach, pear, plum). We also determined if attract-and-kill had any detrimental effects on naturally occurring beneficial insects. Based on an acceptable level of crop loss of 2–5% (the level of crop loss growers can tolerate), attract-and-kill suppressed medfly and reduced crop loss below the acceptable level in orchards with additional controls. Attract-and-kill was most effective when combined with either bait spraying, cover spraying or both. Combining attract-and-kill with cover sprays of fenthion resulted in a drop in crop loss of apples from 2.5% to 0.5%. By combining attract-and-kill with weekly bait sprays and two cover spray applications, crop loss fell from 13.7% to 4.3% in peaches, from 6.3% to 5% in nectarines and from 6.3% to 3.7% in pears. Twice weekly bait spraying was the most effective technique at suppressing medfly, providing acceptable control when applied alone, which further improved by combining with attract-and-kill. By combining attract-and-kill with twice weekly bait spraying crop loss fell from 2% to 1% in nectarines and from 4% to 2% in apples. In laboratory trials, attract-and-kill devices killed 100% of brown lacewings ( Micromus tasmaniae Walker) and 94% of transverse ladybeetles ( Coccinella transversalis Fabricius) 24 h after contact. However, orchard samples suggest that it may not pose any significant negative impact on naturally occurring beneficials such as Neuroptera, Hymenoptera, Coleoptera, Thysanoptera and Syrphidae in the field. [ABSTRACT FROM AUTHOR]

• Overfertilization has caused major salinization and acidification in soils used for GVP. • Higher accumulation of nutrients and agrochemicals in soils used for GVP than open-field soils. • Leafy vegetables have the highest levels of contaminants and human health risks. • Human exposure to contaminants derived from GVP requires more investigation. Rapid expansion of greenhouse vegetable production (GVP) in China over the last few decades has substantially promoted vegetable production and farmers' incomes. However, the semi-closed GVP environment can lead to accumulation of soil contaminants and impose a threat to human health through consumption of vegetables. This paper reviews the current environmental soil status and vegetable safety in Chinese GVPs. Furthermore, we propose several lines of future research to better understand the sources and pathways of GVP contaminants and to identify alternative management to achieve sustainable development. Our review suggests that legacy agricultural practices, including intensive application of agrochemicals and frequent irrigation, have led to significant soil acidification and salinization, as well as accumulation of nutrients and emerging contaminants in human-altered and human-transported soils used for GVP and in GVP vegetables. Over fertilization has led to very low nutrient use efficiencies, particularly for phosphorus and nitrogen. In addition, high inputs of manure, plastic films, and pesticides have promoted significant accumulation of organochlorines, antibiotics, phthalic acid esters, and heavy metals in soils and vegetables at levels exceeding or close to their permitted environmental threshold values. Leafy vegetables with large surface area have the highest levels of contaminants which, in turn, can cause health risks to consumers. Nevertheless, the sources and the paths of contaminants entering the soils and vegetables have not been widely investigated, particularly in the southwestern and northern Chinese provinces. Future research should include detailed documentation of agrochemicals and soil properties involved in the retention, degradation, and mobilization of contaminants. Furthermore, new cleaning technologies should be taken in practice to mitigate or prevent contamination of soil and vegetables. [ABSTRACT FROM AUTHOR]