Altitudinal range is widely used as a proxy of habitat heterogeneity to explain broad-scale geographical patterns of species diversity. Though altitudinal range is a factors derived from altitudinal gradient, altitudinal range’s effects on species diversity on altitudinal gradient remain little known. Based on large scale information of plant species, climatic and geographical factors, we investigated the altitudinal patterns of plant species diversity in the East Himalaya regions, and the effects of altitudinal range on species diversity on altitudinal gradient. We constructed two coefficients, ARDMA (altitudinal range divided by median altitude) and SDDAR (species diversity divided by altitudinal range). We used Spearman’s rank correlation to examine the associations among all of factors. Our results showed that species diversity decreased as the increase of altitude, and significantly related to potential evaporation. No significant correlation was observed between altitudinal range and species diversity, whereas ARDMA significantly related to species diversity, suggesting that only when altitudinal gradient was controlled, were there significant correlations between altitudinal range and species diversity. SDDAR significantly and negatively related to median altitude. We concluded that energy availability significantly affected the altitudinal patterns of species diversity, and altitudinal gradient may shadow the effects of altitudinal range on species diversity.

To enhance our understanding on plant invasions in China, we conducted a comparative study of the checklists of the alien invasive plants in China published during 1998-2008. Our results showed that species diversity of the invasive plants in China was relatively small, in consideration of the huge flora and diverse habitats in China. The results also indicated that there was a big turnover of species composition among the seven checklists. The fast-growth of species diversity of alien invasive plants during 1998-2008 and the exponentially increasing trend confirmed the early warnings. There was an increasing trend observed on those from Asia and Africa from 1998-2008. We suggested that extensive and intensive communication was pressingly needed among ecologists, taxonomists and authors of the checklists. The establishment of the checklist of alien invasive plants with high reliability and timely maintenance, which can accommodate the rapid turnover of the invaders, was one of the chief tasks in the research of plant invasions in China.

Located in Southwest China, Northwest Yunnan has drawn much attention around the world because of its high plant richness. However, spatial associations among different diversity measures of seed plants in this region remain elusive. We compiled a database of spatial distribution of total, endemic, and threatened seed plants at county scale in Northwest Yunnan, and examined spatial associations among the three diversity measures and altitudinal range. We found similar spatial patterns of the three diversity measures, which were highest in the northern part of the region. Moreover, strong correlations among the three diversity measures were observed. Altitudinal range was positively correlated with total and endemic species diversity, while endemic species diversity explained more spatial variation of threatened species diversity. The spatial patterns of all three diversity measures were directly or indirectly correlated with altitudinal range, suggesting strong associations among controlling factors of the three diversity measures. Overall, our results showed strong spatial correlations among total, endemic, and threatened plant diversity in Northwest Yunnan, which should help land managers design cost-effective conservation plans in this region.