Seasonal variations of transpiration efficiency coefficient of irrigated wheat.

Global diminishing water resources, especially due to climate change have serious impacts on evaporation (E) from the soil surface, transpiration (T) from plants (crops) and grain yield, which relates to water use efficiency of different crops. A study was conducted at Kenilworth over two wheat cropping seasons (2007 and 2008) with the objectives of: (i) evaluating the effect of soils and seasons on T, E and yield, and (ii) relating these parameters to transpiration efficiency coefficient. The treatments included two soil types and two soil surface treatments (bare and mulched), which were all replicated four times.

Are there consistent grazing indicators in Drylands? Testing plant functional types of various complexity in South Africa's Grassland and Savanna Biomes.

Despite our growing knowledge on plants' functional responses to grazing, there is no consensus if an optimum level of functional aggregation exists for detecting grazing effects in drylands. With a comparative approach we searched for plant functional types (PFTs) with a consistent response to grazing across two areas differing in climatic aridity, situated in South Africa's grassland and savanna biomes. We aggregated herbaceous species into PFTs, using hierarchical combinations of traits (from single- to three-trait PFTs).