CASE STUDY VINEYARD NUTRIENTS AT BROOKWOOD ESTATE MARGARET RIVER, WESTERN AUSTRALIA T3 SGS 1086 - CS52 ISSUED AUGUST 2012 A.W. MANN INTRODUCTION Ten essential nutrients can be analyzed on the ICP-MS after MMI extraction. Of these, five, namely Ca, K, Mg, P and S are considered as macronutrients because these elements are found in the percent range in plant material. The five micronutrients, Cu, Fe, Mn, Mo and Zn are normally found in the ppm range in plant material. Nutrients N, B and Cl cannot be analyzed using the MMI technique. Nitrogen is of limited importance to viticulturists as it can impart a muddy or musty flavor to wine and vineyards are seldom fertilized with high N fertilizer. Boron is an element with a small range between deficiency and excess; it is a light element not accessible to analysis in an ICP-MS instrument. Chloride is used in the extraction solution and thus cannot be quantified in the soil. Over two thousand agricultural soil samples from Australia and Europe have been analyzed by the MMI technique. Table 1 summarizes the results for nutrients into three broad categories. The nutrients which can be analyzed by the MMI method are all elements which are important to vine growth and vineyard management. In addition to the ten nutrients, cerium and nickel have been analyzed and included in this survey as they are useful diagnostic elements for underlying lithology. Many nutrients are added annually in fertilizer and depleted as fruit and cuttings are exported from the vineyard; an annual soil inventory is a useful viticulture management tool. LOW RANGE NORMAL RANGE HIGH RANGE Ca <200 ppm 200-400 ppm >400 ppm Cu <2000 ppb 2000-4000 ppb >4000 ppb Fe <20 ppm 20-40 ppm >40 ppm K <20 ppm 20-40 ppm >40 ppm Mg <40 ppm 40-80 ppm >80 ppm Mn <4000 ppb 4000-8000 ppb >8000 ppb Mo <20 ppb 20-40 ppb >40 ppb P <2 ppm 2-4 ppm >4 ppm S <10 ppm 10-20 ppm >20 ppm Zn <1000 ppb 1000-2000 ppb >2000 ppb Table 1. Nutrient concentrations ranges in agricultural soils by MMI Australia and Europe.
BACKGROUND The Brookwood Vineyard is 10km north of Margaret River and was planted to vines in the early 1990 s. Prior to this it had been cleared for pastoral uses. It lies close to the boundary between the Proterozoic Leeuwin Block and Cretaceous sediments. Soils are locally known as mungite ; pale brown sandy loams developed over pallid zone clays. The winery itself sits on a laterite ridge evidence for recent mobility of iron in the profile. The vineyard consists of a front and rear vineyard. The front vineyard of approximately one hectare is planted to chenin and sauvignon blanc varieties, whilst the rear vineyard of slightly larger area is planted to semillon, cabernet sauvignon and shiraz. A photograph of the front vineyard is shown in Figure 1. The vineyard has been well fertilized since its inception; soil analyses have been done on an element by element and season by season basis by commercial advisors and laboratories. Approximately five years ago a comprehensive soil survey similar to this one was undertaken by the present author with a pre-cursor proprietary extraction to MMI. In this survey a deficiency of Ca and Mg was identified in the front vineyard. It had badly affected the yield of chenin and was looking potentially fatal to the plants. Through the analysis this problem was attributed to low acidity, generated by the high Fe mobility and subsequent oxidation with release of acid. This was successfully treated with a high one-off application of dolomite. Chenin yields and quality improved markedly. Late last year the manager identified an early season growth abnormality in the rear vineyard (suspected P deficiency) which was successfully temporarily treated with foliar spray. Figure 1. Brookwood Estate, Margaret River, Western Australia. Brookwood Front Vineyard Chenin, Sauvingnon Blanc Figure 2. Locations of samples from the front vineyard, Brookwood Estate. Both the front and rear vineyards were sampled in March of 2012 and the MMI results form the basis of this case history. In addition a number of compost components were sampled and their analysis will be reported here.
FRONT VINEYARD The locations of samples taken from the front vineyard are shown in Figure 2. Samples were taken from a depth of 10-25cm mid row. It will be noted that two samples, one off the SW corner and one off the NE corner have been taken as background. As well as importantly providing useful information on the natural i.e. non-fertilized soil, these samples provide the boundaries for the rectangular plots in Surfer software. Surfer isotropic kriged images for the five micronutrients plus Ce are shown for the front vineyard in Figure 2. The MMI images for Ca and Mg show that the previously observed deficiency for these elements remains under control after the dolomite application, in that both nutrients are present in above normal or normal concentrations, and in the case of Ca above the background levels in the SW and NE corners. The image for P (Figure 2d) shows P to be depleted within the centre of the vineyard relative to the edges and relative to the two background samples in the SW and NE corners. Soil levels for K and S are in general above normal. The soil image for Ce shows levels of this element below levels associated with granitoid rocks i.e. the vineyard sits to the east of the Leeuwin Proterozoic Block on Cretaceous sediments. Images for the micronutrients and Ni are shown in Figure 3. Figure 2. Soil distribution patterns for calcium, potassium, magnesium, phosphorous, sulphur and cerium in the front vineyard, Brookwood Estate after MMI extraction and analysis. Figure 2(a). MMI soil image for Ca Figure 2(b). MMI soil image for K. Figure 2(c). MMI soil image for Mg. Figure 2(d). MMI soil image for P. Figure 2(e). MMI soil image for S. Figure 2(f). MMI soil image for Ce.
Figure 3(a). MMI soil image for Cu. Figure 3(b). MMI soil image for Fe. Figure 3(c). MMI soil image for Mn. Figure 3(d). MMI soil image for Mo. The MMI image for Cu for the front vineyard shows this element to be well above normal levels in the centre of the vineyard, and well above the natural levels in the background samples, possibly due to its being used in a mildew- controlling spray. The elements Fe, Mn and Zn conversely show higher levels in the SW and NE corner background locations, Figure 3(e). MMI soil image for Zn. indicating that the underlying lithology provides more than adequate levels of these elements. Mo shows the result of being adequately added in fertilizer (albeit either added or consumed unequally), whilst the level of Ni is consistent with the parent lithology being sediments and not mafic rock types. Figure 3(f). MMI soil image for Ni. Figure 3. Soil distribution patterns for copper, iron, manganese, molybdenum, zinc and nickel for the front vineyard, Brookwood Estate after MMI extraction and analysis.
Figure 5(a).MMI soil image for Ca. Figure 5(b). MMI soil image for K. Figure 4. Locations of samples in the rear vineyard. REAR VINEYARD The locations of samples taken in the rear vineyard are shown in Figure 4. In this case note that the background samples have been taken off the W side (BW143) and NE corner (BW128) of the vineyard. Surfer images for the macronutrients and Ce for the rear vineyard are shown in Figure 5. Figures 5(a), and (c) show that nutrient levels for Ca, and Mg for the rear vineyard are in the normal range. Potassium has higher than normal values in some sectors, whilst P shows a below normal level on the eastern side consistent with the vineyard manager s observations early in the growing season. Levels for S are normal or above average, whilst the image for Ce again suggests absence of granitoid material in the substrate i.e. the vineyard is on Cretaceous sediments. Figure 5(c). MMI soil image for Mg. Figure 5(d). MMI soil image for P. Figure 5. Soil distribution patterns for calcium, potassium, magnesium, phosphorous, sulphur and cerium in the rear vineyard, Brookwood Estate after MMI extraction and analysis. Figure 5(e). MMI soil image for S. Figure 5(f). MMI soil image for Ce.
The images for micronutrients for the rear vineyard are shown in Figure 6. The images in Figure 6(a) and (b) show levels for Cu and Fe are above normal in the vineyard. In the case of Fe (and in the case of Mn) this is no doubt due to the levels available naturally, but in the case of Cu it is probably the result of Cu spray used in the control of mildew. The image for Zn (Figure 6(e) also shows high levels in the two background samples although levels within the vineyard are in the normal to low range, no doubt due to uptake by the vines. The levels for Ni in Figure 6(f) show that there is not mafic or ultramafic lithology underlying the vineyard, consistent with it being on Cretaceous sediments. Figure 6. Soil distribution patterns for copper, iron, manganese, molybdenum, zinc and nickel in the rear vineyard, Brookwood Estate after MMI extraction and analysis. Figure 6(a). MMI image for Cu. Figure 6(b). MMI image for Fe. Figure (c). MMI image for Mn. Figure 6(d). MMI image for Mo. Figure 7. Locations of compost components and test site. COMPOST COMPONENTS Many of the Margaret River wineries utilize waste from their vineyard and wineries to produce compost. In the case of Brookwood Estate the compost is comprised of wine skins (must), cow manure, tree mulch and rock fines. The 20 tonnes or so of compost is roughly mixed and then stored on a site to the north-east of the rear vineyard. Figure 6(e). MMI image for Zn. Figure 6(d). MMI image for Ni.
Figure 8(a). CPM for Ca. Figure 8(b). CPM for K. Figure (c). CPM for Mg. Figure 8(d). CPM for P. Duplicates were taken of the compost heap (BW121 and BW122). One sample of the fines (BW203), the background soil (BW202), and the field site one month after addition of compost (BW201) were also taken. The following classed post maps (CPMs) show the concentrations of various elements numerically and with a simple colour code. Figure 8 shows CPMs for the macronutrients and Ce. The Classed Post Maps show calcium, potassium and phosphorous to be at maximum concentrations in the compost heap, and magnesium to be at a maximum in the rock fines. Cerium is at lowest concentration in the rock fines indicating it to be of a mafic rock type, not granitic. In most cases the field site shows an increase of macronutrient concentrations after application of the compost. The exceptions are phosphorous where there appears to be an abnormally high value in the background sample (5.8ppm), and for cerium which is at higher (natural) concentrations in the soil than in the compost or rock fines. Figure 8(e). CPM for S. Figure 8(f). CPM for Ce. Figure 8. Classed Post Maps for macronutrients calcium, potassium, magnesium, phosphorous, sulphur and cerium in compost and in a test site.
Figure 9(a). CPM for Cu. Figure 9(b). CPM for Fe. Figure 9(c). CPM for Mn. Figure 9(d). CPM for Mo. Classed Post Maps for the micronutrients and nickel for the compost components are shown in Figure 9. Iron, manganese and zinc are higher in the natural soils than in compost or the rock fines. Figure 9 also shows molybdenum, copper and nickel are highest in the rock fines, the latter confirming that the rock fines are mafic, probably a dolerite (used in road making). Unlike for macronutrients, the application of this compost probably does not have great beneficial effects for micronutrients. Figure 9(e). CPM for Zn. Figure 9(f). CPM for Ni. Figure 9. Classed Post Maps for copper, iron, manganese, molybdenum, zinc and nickel in compost, fines and in a test site.
CONCLUSIONS The MMI extraction and analysis appears to provide sensible and useable information regarding the bioavailability of nutrients in the vineyard situation. Ten nutrients can be analyzed from the one extraction solution a distinct advantage over current partial extraction methodology applied to agriculture. It has also been shown that a small number of samples can be used to provide an image map for each nutrient in a particular vineyard block thus allowing special attention to be paid to specific nutrient requirements of different parts of the vineyard. When two samples are allocated to background, on the SW and NE margins of the block useful information regarding natural soil nutrient levels, nutrient status of the vineyard relative to natural soils,and drawdown of nutrients can be obtained. Plotting is also facilitated since Surfer uses the lowest easting and highest northing to define the rectangular plot. The elements Ce and Ni can provide useful information regarding underlying lithology. SGS Group Management SA 2012 All rights reserved - SGS is a registered trademark of SGS Group Management SA CONTACT INFORMATION Email us at minerals@sgs.com www.sgs.com/mmi