Boron environmental chemistry

Boron and arsenic are natural components of soil and are both present as oxyanions. Boron is present as boric acid or borate polymers, and arsenic is present as arsenate. While boron is weakly held by soil, arsenic is similar to phosphate in its interactions with soil constituents. Boron is an essential nutrient for plants however, it is also toxic to plants at relatively low levels. Arsenic is toxic. The laboratory chemistry of both of these elements is well understood, but their environmental chemistry, speciation and movement, is less well understood [23-27],... 

It is important to note that the presence of polyborate anions, as shown in Figure 2, is only significant in relatively concentrated solutions. This is relevant to the environmental and biological aspects of boron chemistry, since boron is present in both natural waters and biological systems at low concentrations. Under these conditions, only B(OH)3 and B(0H)4 are significant species and at near neutral pH, the concentration of the B(OH)4 anion is minor. Ocean waters contain an average boron concentration of about 4.6 g j,g g which is almost entirely present in the form of naturally occurring boric acid. Boron in plants and animals is also present mainly as boric acid, even if the dietary source of boron is a borate salt. 

The first section of the volume is dedicated to stable isotopic studies of all kinds. Included in this section are investigations of carbon, sulfur, oxygen and boron from terrestrial and extraterrestrial systems. The second section of the volume focuses on geochemical investigations of environmental and atmospheric chemistry problems. The third section of the volume is concerned with various aspects of petroleum geochemistry, and the final section includes investigations of recent and ancient sediments. 

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