A productive concept, or “theory” in ecological jargon, trikes just the right balance between abstract universality nd specific applicability. Too abstract, and ecologists will gnore it as too aloof; too specific, and it will not cross ub-disciplinary boundaries and fade away. Darwin’s Thery of Natural Selection fits this bill, as does MacArthur Wilson’s Island Biogeography. Will Vellend’s Theo...

The fitness of any organisms includes the survival and reproductive rate of adults and the survival of their offspring. Environmental selection pressures might not affect these two aspects of an organism equally. Assuming that an organism first allocates its limited resources to maintain its survival under environmental selection pressure, our model, based on the evolutionarily stable strategy ...

Indigenous groups offer alternative knowledge and perspectives based on their own locally developed practices of resource use. We surveyed the international literature to focus on the role of Traditional Ecological Knowledge in monitoring, responding to, and managing ecosystem processes and functions, with special attention to ecological resilience. Case studies revealed that there exists a div...

The size distribution of the language populations in New Guinea, which represent over 15% of the world's languages, is analysed using models analogous to the resource division models of species abundance distribution in ecological communities. A model distribution of resource segments reflecting population size is created by repeated selection of an existing resource segment and its division in...

We focused on two issues: answer selection and confidence estimation. We found that some simple constraints on the candidate answers can improve a pure IR-based technique for answer selection. We also found that a few simple features derived from the questionanswer pairs can be used for effective confidence estimation. Our results also confirmed findings by Dumais et al, 2002 that the World-Wid...

We describe BBN’s Question Answering work at TREC 2002. We focus on two issues: answer selection and confidence estimation. We found that some simple constraints on the candidate answers can improve a pure IRbased technique for answer selection. We also found that a few simple features derived from the question-answer pairs can be used for effective confidence estimation. Our results also confi...

farmers in the indus basin, pakistan have generally switched to groundwater for additional water supplies due to the irregular supply of irrigation water; currently over 50% of the agricultural land in the basin is at least partially irrigated by tube-wells. these wells pump fresh groundwater, which essentially is the result of massive leakage from irrigation canals into the originally saltwate...

The form of Darwinian selection has important ecological and management implications. Negative effects of harvesting are often ascribed to size truncation (i.e. strictly directional selection against large individuals) and resultant decrease in trait variability, which depresses capacity to buffer environmental change, hinders evolutionary rebound and ultimately impairs population recovery. How...

The level of land consumption for housing and transport contrasts sharply with both the necessity and the legal obligation to maintain the ecological potential afforded by open spaces to meet the needs of current and future generations in terms of resource protection and climate change. Owing to the increasing intensity of soil usage, in many urban landscapes the soil conditions has deteriorate...