title: Gains and losses in C and N stocks of New Zealand pasture soils depend on land use

authors: Schipper, Louis A.

subjects: soil carbon

abstract: Previous re-sampling of 31 New Zealand pasture soil profiles to 1 m depth found large and significant losses of C and N over 2–3 decades. These profiles were predominantly on intensively grazed flat land. We have extended re-sampling to 83 profiles, to investigate whether changes in soil C and N stocks were related to land use. Over an average of 27 years, soils (0–30 cm) in flat dairy pastures lost 0.73 ± 0.16 Mg C ha⁻¹ y⁻¹ and 57 ± 16 kg N ha⁻¹ y⁻¹ but we observed no significant change in soil C or N in flat pasture grazed by “dry stock” (e.g., sheep, beef), or in grazed tussock grasslands. Grazed hill country soils (0–30 cm) gained 0.52 ± 0.18 Mg C ha⁻¹ y⁻¹and 66 ± 18 kg N ha⁻¹y⁻¹. The losses of C and N were strongly correlated, and C:N declined significantly. Further, results reported to 60 and 90 cm show that the pattern of losses and gains extend beyond the IPCC accounting depth of 30 cm. Specific causes for the soil C and N changes are unknown, but appear to be related to land use. In general, the losses under dairying correspond to systems with greater stocking rates, fertiliser inputs and removal of C and N in exported products. Gains in hill country pastures may be due to long-term recovery from erosion and disturbance following land clearance. The unexpected and contrary changes of C and N in different pasture systems (initially thought to be at steady state) demonstrates the need for global and national-scale collection of robust data investigating soil biogeochemical changes, not only for grasslands but also for other land uses. Re-sampling of soils can constrain the directions and magnitude of soil C and N change associated with land use and management to underpin C and N inventories and correctly identify mitigation options.

text: Gains and losses in C and N stocks of New Zealand pasture soils depend on land use Previous re-sampling of 31 New Zealand pasture soil profiles to 1 m depth found large and significant losses of C and N over 2–3 decades. These profiles were predominantly on intensively grazed flat land. We have extended re-sampling to 83 profiles, to investigate whether changes in soil C and N stocks were related to land use. Over an average of 27 years, soils (0–30 cm) in flat dairy pastures lost 0.73 ± 0.16 Mg C ha⁻¹ y⁻¹ and 57 ± 16 kg N ha⁻¹ y⁻¹ but we observed no significant change in soil C or N in flat pasture grazed by “dry stock” (e.g., sheep, beef), or in grazed tussock grasslands. Grazed hill country soils (0–30 cm) gained 0.52 ± 0.18 Mg C ha⁻¹ y⁻¹and 66 ± 18 kg N ha⁻¹y⁻¹. The losses of C and N were strongly correlated, and C:N declined significantly. Further, results reported to 60 and 90 cm show that the pattern of losses and gains extend beyond the IPCC accounting depth of 30 cm. Specific causes for the soil C and N changes are unknown, but appear to be related to land use. In general, the losses under dairying correspond to systems with greater stocking rates, fertiliser inputs and removal of C and N in exported products. Gains in hill country pastures may be due to long-term recovery from erosion and disturbance following land clearance. The unexpected and contrary changes of C and N in different pasture systems (initially thought to be at steady state) demonstrates the need for global and national-scale collection of robust data investigating soil biogeochemical changes, not only for grasslands but also for other land uses. Re-sampling of soils can constrain the directions and magnitude of soil C and N change associated with land use and management to underpin C and N inventories and correctly identify mitigation options.

year: 2010

title: Families of classical subgroup separable superintegrable systems

authors: Kalnins, Ernie G.

subjects: mathematics

abstract: We describe a method for determining a complete set of integrals for a classical Hamiltonian that separates in orthogonal subgroup coordinates. As examples, we use it to determine complete sets of integrals, polynomial in the momenta, for some families of generalized oscillator and Kepler–Coulomb systems, hence demonstrating their superintegrability. The latter generalizes recent results of Verrier and Evans, and Rodríguez, Tempesta and Winternitz. Another example is given of a superintegrable system on a non-conformally flat space.

text: Families of classical subgroup separable superintegrable systems We describe a method for determining a complete set of integrals for a classical Hamiltonian that separates in orthogonal subgroup coordinates. As examples, we use it to determine complete sets of integrals, polynomial in the momenta, for some families of generalized oscillator and Kepler–Coulomb systems, hence demonstrating their superintegrability. The latter generalizes recent results of Verrier and Evans, and Rodríguez, Tempesta and Winternitz. Another example is given of a superintegrable system on a non-conformally flat space.

year: 2010

title: Indigenous Rights Hollow Rights?

authors: Toki, Valmaine

abstract: The Declaration on the Rights of Indigenous Peoples (“the Declaration”) was the initiative of the Working Group on Indigenous Populations (“WGIP”). Established in 1982, the mandate of the WGIP was to develop international standards concerning Indigenous peoples’ rights. The Declaration was a manifestation of this mandate and a clear articulation of international standards on the rights of Indigenous peoples. It was not until 25 years later, in September 2007, that the final text was adopted by the General Assembly with a majority of 143 states in favour. Eleven states offered abstentions. Four states opposed adoption: Australia, Canada, the United States of America (“the United States”) and New Zealand.

text: Indigenous Rights Hollow Rights? The Declaration on the Rights of Indigenous Peoples (“the Declaration”) was the initiative of the Working Group on Indigenous Populations (“WGIP”). Established in 1982, the mandate of the WGIP was to develop international standards concerning Indigenous peoples’ rights. The Declaration was a manifestation of this mandate and a clear articulation of international standards on the rights of Indigenous peoples. It was not until 25 years later, in September 2007, that the final text was adopted by the General Assembly with a majority of 143 states in favour. Eleven states offered abstentions. Four states opposed adoption: Australia, Canada, the United States of America (“the United States”) and New Zealand.

year: 2011