Water quality assessment for sustainable agriculture in the Wet Tropics--a community-assisted approach

A number of studies in north Queensland over the past two decades have concluded that large amounts of nutrients and sediments are exported from agricultural watersheds, particularly during wet season rainfall events. With the co-operation of a number of growers, runoff from Queensland Wet Tropics banana and cane farm paddocks in two distinct tropical river catchments was examined to provide an estimate of nutrient and sediment concentrations and export, with comparison to water quality of flow through a small urban lakes system. Median total nitrogen concentrations in cane drainage runoff (3110 microg N/L) were higher than for banana paddock drainage (2580 microg N/L), although the maximum concentration was recorded from a banana paddock (20,900 microg N/L). Nitrogen losses during post-event drainage flow were supplemented by high proportions of NO(X) (nitrate + nitrite) sourced from groundwater inputs. Banana paddocks had the highest maximum and median total phosphorus and TSS concentrations (5120 and 286 microg P/L, and 7250 and 75 mg/L respectively) compared to the cane farms (1430 and 50 microg P/L, and 1840 and 14 mg/L respectively). The higher phosphorus and TSS concentrations in the banana runoff were attributed to higher paddock slopes and a greater proportion of exposed ground surface during the wet season. Highest nutrient and TSS concentrations corresponded with samples collected near the peak discharge periods; however, the rising stage of the drainage flows, where the highest nutrient and TSS concentrations are often reported, were difficult to target because of the manual sampling strategy used. This study shows that high concentrations of nutrients and TSS occur in the runoff from cane and banana paddocks. Median total nitrogen, total phosphorus and TSS concentrations in flow through the urban lakes were 369 microg N/L, 16 microg P/L and 11 mg/L, respectively. Flux estimates of 9.2 kg N, 0.8 kg P and 126 kg TSS/ha were determined for drainage runoff from a banana paddock during a single intensive storm event.     

Pricing China's irrigation water

Many development agencies and other actors are advocating that China adopt a system of water markets or of high water prices in order to resolve the inefficiencies of irrigation agriculture and to supply sufficient water for growing urban and industrial uses. We argue that this proposal rests on a series of propositions: that the price of water is too low to encourage farmers to be efficient; that farmers are not charged volumetric prices and so are not encouraged to conserve water; that water is scarce largely because farmers are profligate in their use of water; and that proper pricing of water will not affect equity. None of these contentions is true. Farmers have to pay not only the official charges for water but also the much higher costs of pumping it onto their fields. Once pumping is included, farmers are paying prices that are volumetric. Furthermore, the inefficiency of farmers arises in large part from the manner in which water is delivered to them: the system offers no rewards for care in the use of water and instead rewards greed. And, finally, although it might be true that higher prices do not affect equity within a village, in fact they would have substantial effects on inter-sectoral equity, with farmers becoming worse off in comparison to urban dwellers. The paper concludes by sketching a more appropriate scheme for raising the efficiency of use of irrigation water.     

Emotional Encounters in Sacred Spaces: The Case of the Church of Jesus Christ of Latter-day Saints

Individual experience and emotion are critical to a complete understanding of the transformative effect of sacred spaces on people's lives. We implement an in-depth qualitative examination of the spiritual experiences from members of the Church of Jesus Christ of Latter-day Saints. They were allowed the opportunity to freely articulate their emotions when attending meetinghouses and temples as well as discuss the spiritual significance of these sites. We found that these spaces transcended the “everyday,” had a considerable capacity to inspire emotio-spiritual encounters, particularly feelings of peace, and further served as evidence of a deeper individual gradation of sacred space.     

Some results from recent chemical studies at Kilauea volcano,Hawaii

The chemical surveillance of Kilauea volcano, Hawaii, has continued. No relationship has thus far been identified between the helium content of an associated fumarole and the activity at the volcano. Fume samples from Halemaumau crater in Kilauea caldera and from a fissure eruption that occurred nearby on the floor of the caldera during August 1971 were examined for their halogen (Cl and F) and sulfur contents. The ratio of Cl/F in fume showed an abnormal increase in samples taken at Halemaumau a month before the eruption. This change in ratio may be a helpful indicator of the onset of eruption in volcanic areas.     

Determination of dissolved organic matter in streamwater using visible spectrophotometry: A comment

A discussion querying the need (Grieve, 1985) for further studies on the use of the technique, which is already well established. The use of chemical oxygen demand is also questioned.     

Evidence against early nineteenth century major European induced environmental impacts by illegal settlers in the New England Tablelands,south eastern Australia

Paleoenvironmental reconstructions from Little Llangothlin Lagoon have been used to argue for early European impact on the eastern Australian landscape. In particular, these studies have argued for European arrival on the New England Tablelands at about 1800 AD, with significant impacts including the clearance of one species of Casuarina before 1820 AD and significant erosion by 1836 AD (Gale et al., 1995; Gale and Pisanu, 2001; Gale and Haworth, 2002, 2005). We have re-cored the lagoon, dated the cores using ²¹⁰Pb and radiocarbon, and counted pollen and other proxies. Our ²¹⁰Pb results indicate that ²¹⁰Pb background was achieved stratigraphically later than the erosion event and we have three early Holocene radiocarbon ages in the erosion event interval. We conclude that the ‘erosion event’ predates European settlement. The ²¹⁰Pb results indicate much less erosion in response to European settlement than suggested by these earlier studies. We also find no notable decline in Casuarina in the pollen record spanning the time of initial European impact, and in fact we find very little Casuarina in the record. Instead of a Casuarina dominated vegetation we conclude that the area was dominated by open Eucalypt forest prior to European settlement. Rather than changes in the regional vegetation in the early 19th century, we attribute changes in the palynoflora spanning the ‘erosion event’ to changes within the lake/wetland and in particular to changes in the dominance of different species of Myriophyllum; most likely due to water depth fluctuation. This site has stood out as indicating an earlier European impact than other localities in eastern Australia, beyond the original limits of settlement near Sydney. Our findings suggest that a more traditional interpretation of this site is warranted and that no very early impact is discernable.     

Leatherback turtles: The menace of plastic

The leatherback, Dermochelyscoriacea, is a large sea turtle that feeds primarily on jellyfish. Floating plastic garbage could be mistaken for such prey. Autopsy records of 408 leatherback turtles, spanning 123 years (1885-2007), were studied for the presence or absence of plastic in the GI tract. Plastic was reported in 34% of these cases. If only cases from our first report (1968) of plastic were considered, the figure was 37%. Blockage of the gut by plastic was mentioned in some accounts. These findings are discussed in the context of removal of top predators from poorly understood food chains.