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A useful spatial pattern of cultivated land utilization in mountainous areas is a basic prerequisite for promoting efficient utilization of cultivated land and has a practical use for ensuring regional food security and rural revitalization. In this paper, we use Enshi and Lichuan cities as case studies and the PLUS model to analyze the spatial differentiation characteristics of cultivated land from 2000 to 2020. In addition, we simulated the spatial pattern of cultivated land in 2030 concerning the ecological priority scenario (scenario I) and the ecological and economic coordination scenario (scenario II). The results show that (1) the degree of cultivated land fragmentation from 2000 to 2020 is characterized as "high in the east and low in the west," and the spatial aggregation of cultivated land decreases slightly over time and that there is a risk of increasing fragmentation of cultivated land in the future. (2) The complexity of cultivated land shape shows a fluctuating decrease between 2000 and 2030, and an overall trend of landscape homogenization. (3) The spatial distribution of cultivated land is concentrated in the peak cluster depressions and river valleys. The imbalance in the distribution of cultivated land has increased in the past two decades which should be curbed in the future. (4) In 2030, concerning the ecological priority development scenario, cultivated land use tends to evolve in the direction of balanced distribution and a relatively complex shape. (5) Concerning the coordinated ecological and economic development scenario, the spatial aggregation of cultivated land is higher and the patches of cultivated land are more regular, but the distribution imbalance is more serious. The results can provide scientific references for sustainable and effective use of cultivated land in mountainous areas. [ABSTRACT FROM AUTHOR]

Since 2004 the oriental fruit fly, Bactrocera dorsalis (Hendel) has become widespread and economically important in Wuhan, Hubei Province, central China. In this article, the population dynamics of B. dorsalis were monitored using methyl eugenol-baited traps during 2008-2009 in Wuhan. Adults were captured from early July to the end of December in a citrus orchard and peaked in October and early November. Adult population peak coincided with the ripeness period of sweet oranges in October. Infestation with B. dorsalis was more serious in 2009 than in 2008. Field surveys of host plants for this fly species combined with rearing experiments indicated that pear was the first host plant infested by B. dorsalis. We recorded the following host shift pattern: pear ( Pyrus communis L.), jujube ( Zizyphus jujuba L.), persimmon ( Diospyros kaki L.), and sweet orange ( Citrus unshiu Marcor). Our findings suggest that B. dorsalis completes four to five generations per year in this area and most serious damage occurred in the 4th generation in the citrus orchards. The availability of preferred host fruits and the low winter temperature are key factors influencing population fluctuations. Overwintering potential experiments of adults, larvae, and pupae were also carried out in the field. Results suggest that a small proportion of pupae were able to survive winter in Wuhan and emerged successfully the following year. Practical and theoretical implications of the results regarding the invasion potential and management strategy of B. dorsalis in Hubei Province are discussed. [ABSTRACT FROM AUTHOR]