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Rice ecosystems vary greatly in climate, edaphic conditions, landscape heterogeneity, agricultural management and biodiversity. However, ongoing land use intensification and conversion to large-scale monoculture are threatening this diversity. We analyzed how rice-growing regions in Southeast Asia differ in diversity and composition of vascular plants in paddy rice ecosystems, and how the local and regional biodiversity of these plants is determined by variations in abiotic conditions, habitat type (paddy vs. bunds) and the proximity of non-paddy habitats. The vegetation of paddies and their bunds was surveyed in seven important rice production regions located in highlands and lowlands of Vietnam and the Philippines. Within the regions we sampled 67 pairs of study sites comprising a total of 122 paddies and 134 bunds. We identified major drivers of field-level weed diversity (alpha diversity) separately for bunds and paddies. Species turnovers (beta diversity) across sampling sites, between paddies and their bunds, and between regions were visualized using the Bray-Curtis coefficient of dissimilarity and DCA ordinations. Species richness on bunds was mainly influenced by the proximity of non-paddy habitats, mean annual temperature and soil acidity. Soil moisture was the decisive factor for the variation in paddy weed richness. In both habitat types, Shannon diversity and the number of insect-pollinated plants showed patterns similar to species richness. Regional differences in plot species richness were stronger on bunds than in paddies. Species turnover was high among habitat types and between upland and lowland regions. Future ecological engineering approaches can build on our findings to promote pollination services more efficiently in Southeast Asian rice landscapes.

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Which plant species can be found on rice field bunds and what are the prevailing life forms? Which plant communities occur and what are the main environmental drivers and phytogeographic patterns shaping these communities? How do species diversity and composition differ between bunds and paddies? To answer these questions, 133 vegetation relevés using the Braun-Blanquet method were collected in lowlands and uplands of Vietnam and the Philippines between 2012 and 2015. Soil samples were collected and farmers were interviewed. Properties of soil, climate, and geography were assessed, further structural parameters, landscape heterogeneity, seasonality, management and intensity of cultivation. Hierarchical UPGMA cluster analysis and NMDS ordinations were performed to visualize variation in plant community composition and the determinants. We found 302 vascular plant species, of which 94 species are red listed by the IUCN (under category “Least concern”). Therophytes and helophytes are the prevailing life forms. Six clusters of plant communities were classified, and temperature, soil acidity, land use intensity and nutrient availability were identified (according to relevance) as explanatory variables. Bunds revealed higher species richness than paddies and bunds in mountain areas were more species-rich than those in the lowlands. We conclude that the composition of bund communities provides valuable information on environmental and biogeographical conditions of the local rice landscapes, and that it is probably the best applicable and most reliable indicator of management intensity.

Two major human-made problems in rice production systems in the north of Vietnam concern the low plant-available silicon content of soils and the low biodiversity. The results of the LEGATO project suggest a change to an environmentally friendly rice production system that will help to recover biodiversity. We propose here a framework for a demonstration and dissemination model that will be exemplary for the farmers once it has been successfully realized. We advocate local-option models in different districts to demonstrate to farmers. The methods should be adapted to local and ecoregional differences in climate and land-use tradition, and they explicitly take into account soil care, organic fertilizer, manual weeding, native nectar-rich plant bunds, manual pest snail collection, hymenopteran nesting aids, and biodiversity and yield monitoring.

Aims: The knowledge of rice weed communities, their diversity, composition, dynamics and distribution is still inadequate. We present information on the plant diversity of rice fields in major Southeast Asian centres of rice cultivation, the prevailing life forms, the plant communities, the main environmental drivers, and phytogeographic patterns that shape these communities. Study area: Seven different regions of Vietnam and the Philippines, including lowland and mountain areas (0–1390 m a.s.l.). Methods: Altogether 115 vegetation relevés using the Braun-Blanquet method were recorded during wet and dry seasons between 2013 and 2015. Soil samples were collected and farmers of surveyed rice fields were interviewed. Vegetation surveys were designed to detect possible effects of soil properties, climate, altitude, geographic location, landscape heterogeneity, seasonality, management and intensity of cultivation, and structural parameters on the paddy vegetation. Hierarchical cluster analysis UPGMA was applied and NMDS ordinations were performed to visualize differences in plant community composition along the different gradients. Results: We found 113 vascular plant species, with annual hydrophytes and therophytes being the prevailing life forms. Sixty of the recorded species appear to be globally rare. We revealed four clusters of plant communities which are explained mainly by soil acidity, crop height and temperature: Paspalum distichum-Hydrolea zeylanica community, Echinochloa crus-galli community, Rotala indica-Monochoria vaginalis community and Fimbristylis littoralis-Leptochloa chinensis community. The two latter communities were further classified into regional subunits. Conclusions: We conclude that the composition of weed communities provides valuable information on environmental and biogeographical conditions of the local rice landscapes, and that it is probably the most applicable and reliable indicator of managementintensity.

In 1999 there were 25 deaths from breast cancer in the Northern Territory (NT), approximately three times as many deaths as occurred in each of the several preceding years, and more than would have been expected due to random variation in the number of breast cancer deaths in any one year. The high number of breast cancer deaths in 1999 appears to be at least partially explained by an increase in the incidence of breast cancer in Aboriginal women (who have, on average, very short survival time) in the preceding three years, and ‘delayed’ deaths of non-Aboriginal women in the three years before 1999 which resulted in a larger number of deaths in 1999. A clinical audit of breast cancer treatment for women who died during 1999 did not reveal any pattern of cancer occurrence or treatment, which could explain the high number of deaths in that year.