title: Cost-effective policies for improving water quality by reducing nitrate emissions from diverse dairy farms: An abatement–cost perspective

authors: Doole, Graeme J.

subjects: agricultural production

abstract: A flexible and replicable approach for the appraisal of the cost-effectiveness of various policy instruments for the regulation of nonpoint pollution from heterogeneous farms is presented. The framework is employed to evaluate three regulatory instruments for achieving reductions in nitrate leaching among a large population of dairy farms in the Waikato region of New Zealand. These instruments are (1) a differentiated policy that allows individual abatement effort to vary among farms to satisfy a catchment-wide reduction in leaching load, (2) a uniform policy that requires all farms to reduce emissions by a constant proportion, and (3) a threshold policy that requires all farms to emit beneath a given threshold leaching load. A 30% reduction in leaching will cost around 1.4, 1.96, and 4.41 million dollars across the catchment with a differentiated, uniform, and threshold policy, respectively. In comparison, a 50% reduction in leaching will cost around 7.77, 8.58, and 11.24 million dollars across the catchment with a differentiated, uniform, and threshold policy, respectively. Thus, a differentiated policy achieves required environmental outcomes at least cost. This result highlights the value of modelling heterogeneous farms in policy evaluation for nonpoint pollution control.

text: Cost-effective policies for improving water quality by reducing nitrate emissions from diverse dairy farms: An abatement–cost perspective A flexible and replicable approach for the appraisal of the cost-effectiveness of various policy instruments for the regulation of nonpoint pollution from heterogeneous farms is presented. The framework is employed to evaluate three regulatory instruments for achieving reductions in nitrate leaching among a large population of dairy farms in the Waikato region of New Zealand. These instruments are (1) a differentiated policy that allows individual abatement effort to vary among farms to satisfy a catchment-wide reduction in leaching load, (2) a uniform policy that requires all farms to reduce emissions by a constant proportion, and (3) a threshold policy that requires all farms to emit beneath a given threshold leaching load. A 30% reduction in leaching will cost around 1.4, 1.96, and 4.41 million dollars across the catchment with a differentiated, uniform, and threshold policy, respectively. In comparison, a 50% reduction in leaching will cost around 7.77, 8.58, and 11.24 million dollars across the catchment with a differentiated, uniform, and threshold policy, respectively. Thus, a differentiated policy achieves required environmental outcomes at least cost. This result highlights the value of modelling heterogeneous farms in policy evaluation for nonpoint pollution control.

year: 2011

title: Paleoliquefaction in Late Pleistocene alluvial sediments in Hauraki and Hamilton basins, and implications for paleoseismicity

authors: Kleyburg, Melissa Anita

abstract: Liquefaction susceptibility of the Late Pleistocene Hinuera Formation is of interest to the engineering community as it is unclear whether materials of this age will still be prone to activation by cyclic stresses. In this paper we report on rare paleoliquefaction features in the form of injection structures that we have identified at two sites near Hamilton. These structures are clearly earthquake induced, and indicate the potential for future liquefaction episodes. However, we suggest that the hazard is restricted to areas with impeded drainage that imparts a high water table. Such areas are localised, and may be recognised from the modern (pedological) soil distribution. Evaluating piezocone penetration test (CPTu) data from the sites of known paleoliquefaction indicates that the CPTu gives a meaningful indication of liquefaction potential, and questions the validity of applying aging factors to these deposits.

text: Paleoliquefaction in Late Pleistocene alluvial sediments in Hauraki and Hamilton basins, and implications for paleoseismicity Liquefaction susceptibility of the Late Pleistocene Hinuera Formation is of interest to the engineering community as it is unclear whether materials of this age will still be prone to activation by cyclic stresses. In this paper we report on rare paleoliquefaction features in the form of injection structures that we have identified at two sites near Hamilton. These structures are clearly earthquake induced, and indicate the potential for future liquefaction episodes. However, we suggest that the hazard is restricted to areas with impeded drainage that imparts a high water table. Such areas are localised, and may be recognised from the modern (pedological) soil distribution. Evaluating piezocone penetration test (CPTu) data from the sites of known paleoliquefaction indicates that the CPTu gives a meaningful indication of liquefaction potential, and questions the validity of applying aging factors to these deposits.

year: 2015-02-22

title: Mining at Te Aroha before the murder in February 1881

authors: Hart, Philip

abstract: Mining was slow to restart after the Christmas holidays on a goldfield whose value was still unknown. Some miners did not return, but other men, mostly with mining experience, replaced them. As was pointed out, more testing was required to justify the cautious optimism, and more explorations did not discover any payable ore or a reef of any sort. More capital was needed to fund adequate development, and the lack of a battery held back the field.
Some searched the nearby countryside, fruitlessly, but at Tui the mostly Maori miners working there seemed to be having better results. Unskilled miners who drove incompetent and even dangerous adits wasted their efforts, while others were accused of shepherding their ground. Two companies formed during January attracted many small investors, but experienced miners started leaving for newer finds, and non-miners abandoned their attempts at mining after discovering that gold was not easy to find. But others remained hopeful, and waited for the erection of a local battery to prove the value of what they had found.

text: Mining at Te Aroha before the murder in February 1881 Mining was slow to restart after the Christmas holidays on a goldfield whose value was still unknown. Some miners did not return, but other men, mostly with mining experience, replaced them. As was pointed out, more testing was required to justify the cautious optimism, and more explorations did not discover any payable ore or a reef of any sort. More capital was needed to fund adequate development, and the lack of a battery held back the field.
Some searched the nearby countryside, fruitlessly, but at Tui the mostly Maori miners working there seemed to be having better results. Unskilled miners who drove incompetent and even dangerous adits wasted their efforts, while others were accused of shepherding their ground. Two companies formed during January attracted many small investors, but experienced miners started leaving for newer finds, and non-miners abandoned their attempts at mining after discovering that gold was not easy to find. But others remained hopeful, and waited for the erection of a local battery to prove the value of what they had found.

year: 2016