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Abstract: Grapevine (Vitis vinifera L.) growth is limited by the hard-setting red duplex soils that occur in many major viticultural regions, including the Goulburn Valley, Victoria. Water often ponds on the soil surface and dense subsoils restrict drainage. An experiment was conducted to develop soil management that improved water infiltration, root growth and grapevine performance. The experiment was conducted from 1995 to 1998 in a vineyard block of Chardonnay on Ramsey rootstock planted at Rosbercon Vineyard, Picola in 1972. Three soil managements were compared over 3 years testing for improved soil physical properties, root growth and grapevine performance. Microjets irrigated the vine-line soil where randomised treatments of grown ryegrass (Lolium multiforum) (Autumn/Winter) or straw mulch (15t/ha year round), gypsum application (12t/ha) and slow (5mm/h) or fast wetting (15mm/h) were applied. Ryegrass growth maintained macropores (0.35cm3/cm3 >30μm diameter) 33 months after tillage, kept the soil soft (<1MPa) to a greater depth (134mm) and had higher concentrations of grapevine roots (5.05cm/cm3 at 0–100mm depth) compared with those of straw mulch (0.31cm3/cm3 macropores, 73mm depth soft soil and 3.35cm/cm3 root length density). Gypsum maintained the surface soil soft for a greater depth (120mm) and improved water penetration to 250mm depth compared with no gypsum application (87mm depth soft soil). Ryegrass and gypsum improved water penetration to 450mm depth compared with ryegrass and no gypsum application. Grapevine vegetative growth (pruning weight), reproductive performance (yield and bunch weight) and root growth were each directly dependent on the depth of soft soil (depth of soil less than 1 and/or 2MPa). Grape yield and bunches per grapevine were also each directly dependent on the volumetric water content at field capacity of the surface soil. These results suggest that, to alleviate limitations of hard-setting red duplex soils to grapevine growth and performance, management should increase coagulation of clay particles and stabilisation of aggregates in order to maximize the depth of soft soil (<2MPa). Moreover, the key soil parameter identified in this study that is most representative as an indicator of quality soil for winegrape production is depth of soft soil (<2MPa) 24h after irrigation. [Copyright &y& Elsevier]

Fertile soil is fundamental to our ability to achieve food security, but problems with soil degradation (such as acidification) are exacerbated by poor management. Consequently, there is a need to better understand management approaches that deliver multiple ecosystem services from agricultural land. There is global interest in sustainable soil management including the re-evaluation of existing management practices. Liming is a long established practice to ameliorate acidic soils and many liming-induced changes are well understood. For instance, short-term liming impacts are detected on soil biota and in soil biological processes (such as in N cycling where liming can increase N availability for plant uptake). The impacts of liming on soil carbon storage are variable and strongly relate to soil type, land use, climate and multiple management factors. Liming influences all elements in soils and as such there are numerous simultaneous changes to soil processes which in turn affect the plant nutrient uptake; two examples of positive impact for crops are increased P availability and decreased uptake of toxic heavy metals. Soil physical conditions are at least maintained or improved by liming, but the time taken to detect change varies significantly. Arable crops differ in their sensitivity to soil pH and for most crops there is a positive yield response. Liming also introduces implications for the development of different crop diseases and liming management is adjusted according to crop type within a given rotation. Repeated lime applications tend to improve grassland biomass production, although grassland response is variable and indirect as it relates to changes in nutrient availability. Other indicators of liming response in grassland are detected in mineral content and herbage quality which have implications for livestock-based production systems. Ecological studies have shown positive impacts of liming on biodiversity; such as increased earthworm abundance that provides habitat for wading birds in upland grasslands. Finally, understanding of liming impacts on soil and crop processes are explored together with functional aspects (in terms of ecosystems services) in a new qualitative framework that includes consideration of how liming impacts change with time. This holistic approach provides insights into the far-reaching impacts that liming has on ecosystems and the potential for liming to enhance the multiple benefits from agriculturally managed land. Recommendations are given for future research on the impact of liming and the implications for ecosystem services. [ABSTRACT FROM AUTHOR]

Abstract: This paper is the first of a series that investigates whether new cropping systems with permanent raised beds (PRBs) or Flat land could be successfully used to increase farmers’ incomes from rainfed crops in Lombok in Eastern Indonesia. This paper discusses the rice phase of the cropping system. Low grain yields of dry-seeded rice (Oryza sativa) grown on Flat land on Vertisols in the rainfed region of southern Lombok, Eastern Indonesia, are probably mainly due to (a) erratic rainfall (870–1220mm/yr), with water often limiting at sensitive growth stages, (b) consistently high temperatures (average maximum=31°C), and (c) low solar radiation. Farmers are therefore poor, and labour is hard and costly, as all operations are manual. Two replicated field experiments were run at Wakan (annual rainfall=868mm) and Kawo (1215mm) for 3 years (2001/2002 to 2003/2004) on Vertisols in southern Lombok. Dry-seeded rice was grown in 4 treatments with or without manual tillage on (a) PRBs, 1.2m wide, 200mm high, separated by furrows 300mm wide, 200mm deep, with no rice sown in the well-graded furrows, and (b) well-graded Flat land. Excess surface water was harvested from each treatment and used for irrigation after the vegetative stage of the rice. All operations were manual. There were no differences between treatments in grain yield of rice (mean grain yield=681g/m2) which could be partly explained by total number of tillers/hill and mean panicle length, but not number of productive tillers/hill, plant height or weight of 1000 grains. When the data from both treatments on PRBs and from both treatments on Flat land, each year at each site were analysed, there were also no differences in grain yield of rice (g/m2). When rainfall in the wet season up to harvest was over 1000mm (Year 2; Wakan, Kawo), or plants were water-stressed during crop establishment (Year 1; Wakan) or during grain-fill (Year 3: Kawo), there were significant differences in grain yield (g/1.5m2) between treatments; generally the grain yield (g/1.5m2) on PRBs with or without tillage was less than that on Flat land with or without tillage. However, when the data from both treatments on PRBs and from both treatments on Flat land, each year at each site, were analysed, the greater grain yield of dry-seeded rice on Flat land (mean yield 1 092g/1.5m2) than that on PRBs (mean 815g/1.5m2) was mainly because there were 25% more plants on Flat land. Overall when the data in the 2 outer rows and the 2 inner rows on PRBs were each combined, there was a higher number of productive tillers in the combined outer rows (mean 20.7tillers/hill) compared with that in the combined inner rows on each PRB (mean 18.2tillers/hill). However, there were no differences in grain yield between combined rows (mean 142g/m row). Hence with a gap of 500mm (the distance between the outer rows of plants on adjacent raised beds), plants did not compensate in grain yield for missing plants in furrows. This suggests that rice (a) also sown in furrows, or (b) sown in 7 rows with narrower row-spacing, or (c) sown in 6 rows with slightly wider row-spacing, and narrower gap between outer rows on adjacent beds, may further increase grain yield (g/1.5m2) in this system of PRBs. The growth and the grain yield (y in g/m2) of rainfed rice (with rainfall on-site the only source of water for irrigation) depended mainly on the rainfall (x in mm) in the wet season up to harvest (due either to site or year) with y =1.1x −308; r 2 =0.54; p <0.005. However, 280mm (i.e. 32%) of the rainfall was not directly used to produce grain (i.e. when y =0g/m2). Manual tillage did not affect growth and grain yield of rice (g/m2; g/1.5m2), either on PRB or on Flat land. [Copyright &y& Elsevier]