关键词: 土地利用/覆被变化, 景观服务评估, 景观服务制图, 景观服务模拟, 尺度

Abstract: Fusarium oxysporum f. sp. niveum, a causal agent of fusarium wilt of watermelon, is a common soilborne pathogen that can decrease the watermelon yield and quality. It denotes one of the major factors limiting current watermelon production. In recent years, many researches have been done on it, including the symptom, occurring conditions, disease cycle and major prevention measures. In actual production, the most commonlyutilized control method is grafting. However, it is difficult to widely apply and popularize the grafted watermelon cultivation method in China. Moreover, the molecular mechanism of watermelon wilt caused by F. oxysporum f. sp. niveum remains unclear. At present, both the ecological and economic problems caused by continuous cropping obstacles of watermelon, such as the weakened regenerative capacity, soil microflora imbalances, soil fertility decline and increased rates of plant diseases, are attracting more attentions from scholars. In this review, the infection and colonization of F. oxysporum, the effects of F. oxysporium toxin on watermelon growth as well as the effects of continuous cropping of watermelon on soil ecosystems are explored. Furthermore, we summarize the underlying mechanism of watermelon continuous cropping obstacles caused by F. oxysporum. Meanwhile, the biological control methods of watermelon fusarium wilt are expounded.

Key words: land use/cover change (LUCC), landscape service evaluation, landscape service mapping, landscape service modeling, scale.