Growing concern over resource use and protection of the environment has prompted greater demand for agricultural policy analysis at the local, regional, and national levels. Faced with declining surface-water quality, silting of reservoirs, and contaminated groundwater supplies, the public has demanded greater protection of the environment. With the call for more regulation of agriculture comes...

Timber harvesting guidelines formulated for north Queensland rainforests allowed economically viable harvests with minimal ecological impact. Harvesting procedures sought to minimize soil erosion, silting and turbidity in steams, destruction of trees in the residual stand, and disruption of natural habitats and processes. Forest officers selected the trees to be harvested, indicated the directi...

Experience with severe frostbite and other similar cold injuries during the recent war demonstrated the inadequacy of our knowledge of these conditions and the need for developing effective means for preventing their serious sequelae. Great controversy exists concerning the proper early treatment of severe frostbite. The radically divergent opinions held arise from disagreement as to the exact ...

A G-system is a collection of Z-bases Zn with some extra axiomatic conditions. There are two kinds actions “mutations” and “Bongartz co-completions” naturally acting on G-system, which provide the combinatorial structure G-system. It turns out that have good compatibility “mutations”. The constructions known before in different contexts, including cluster tilting theory, silting ?-tilting algeb...

This thesis is concerned with higher cluster tilting objects in generalized higher cluster categories and tropical friezes associated with Dynkin diagrams. The generalized cluster category arising from a suitable 3-Calabi-Yau differential graded algebra was introduced by C. Amiot. It is Hom-finite, 2-Calabi-Yau and admits a canonical cluster-tilting object. In this thesis, we extend these resul...

Dredging is a catastrophic disturbance that directly affects key biological processes in aquatic ecosystems, especially in those small and shallow. In the tropics, metabolic responses could still be enhanced by the high temperatures and solar incidence. Here, we assessed changes in the aquatic primary production along a small section of low-flow tropical downstream (Imboassica Stream, Brazil) a...

An investigation was carried out during the rainy period in six semi-intensive production fish ponds in which water flowed from one pond to another without undergoing any treatment. Eight sampling sites were assigned at pond outlets during the rainy period (December-February). Lowest and highest physical and chemical parameters of water occurred in pond P1 (a site near the springs) and in pond ...

Port silting is a common and natural process which often causes serious inconveniences for safe navigation requires expensive dredging operations to keep the port operative. Sediment deposition closely related exchange water between basin surrounding environment; one way limit deposits by reducing flow entering port. However, this may be in contrast with need adequate sediment quality, turn an ...