It is not possible to estimate accurately the extent of different biomes prior to significant human impact, but it is possible to determine the “potential” area of biomes based on soil and climatic [..]
Radiative forcing caused by changes in atmospheric composition, alteration in land surface reflectance (albedo), and variation in the output of the sun for the year 2000 relative to conditions in [..]
While the peculiarities of individual pollutants, rivers, and governance define the specific character of water pollution, the general patterns observed for nitrogen are representative of [..]
Nutrient loading is projected to become an increasingly severe problem, particularly in developing countries. Nutrient loading already has major adverse effects on freshwater ecosystems and coastal [..]
The time scale of change refers to the time required for the effects of a perturbation of a process to be expressed. Inertia refers to the delay or slowness in the response of a system to factors [..]
Timber is harvested from forests and plantations and used for a variety of building, manufacturing, fuel, and other needs. Forests (providing fuelwood and charcoal), agricultural crops, and manure all [..]
While traditional natural resource sectors such as agriculture, forestry, and fisheries are still important in industrial-country economies, the relative economic and political significance of other [..]
For all developing countries over the period 1961–99, expansion of harvested land contributed only 29% to growth in crop production versus the contribution of increases in yields, which amounted to [..]
The cell color indicates impact of each driver on biodiversity in each type of ecosystem over the past 50–100 years. High impact means that over the last century the particular driver has [..]
The twin role played by the skin – protection from excessive UV radiation and absorption of enough sunlight to trigger the production of vitamin D – means that people living in the lower latitudes, [..]
The total value of the carbon market for 2003 topped $300 million. And, depending on international regulation, some observers project that it will increase to $10–40 billion by 2010. Markets are also [..]
From the late 1950s, offshore bottom trawlers began exploiting the deeper part of the stock, leading to a large catch increase and a strong decline in the underlying biomass. Internationally agreed [..]
The range of the natural rate of bacterial nitrogen fixation in natural terrestrial ecosystems (excluding fixation in agroecosystems) is shown for comparison. Human activity now produces approximately [..]
Fisheries catches increasingly originate from deep areas. Over the years due to depletion in fish stocks the fishing industry has resorted to fishing at greater depths and increasing the damage to [..]
Number of new records of established non-native invertebrate and algal species reported in marine waters of North America, shown by date of first record, and number of new records of non-native marine [..]
