Tropical Ecology 51(2S): 303-304, 2010                                                                                                                                                                                                                                                                                                                                                                                          ISSN 0564-3295  
                                                                              © International Society for Tropical Ecology 
                                                                              www.tropecol.com 
                                                                               
                                                                                                               Plant invasion and environmental pollution: causes of concern 
                                                                               
                                                                               
                                                                                                                                                                                                                                                                                                                         1*                                                                                     2  
                                                                                                                                                                                                                                           A.J. HIREMATH  & M. AGRAWAL  
                                                                                                                                                                                                                                                                                                 Guest Editors 
                                                                                                                                                                                                                                                                                                                                
                                                                                       1
                                                                                            Ashoka Trust for Research in Ecology and the Environment, 1 K Block Commercial Complex, 
                                                                                                                                                                                                          Jangpura Extension, New Delhi 110 014, India 
                                                                                                                                  2Department of Botany, Banaras Hindu University, Varanasi 221 005, India 
                                                                                                                                    
                                                                                                Humans, like other organisms, modify their                                                                                                                                                                                              effects of species invasion on vegetation composition, 
                                                                              environment, but the degree to which humans                                                                                                                                                                                                               and on a critical ecosystem process, nutrient 
                                                                              have become capable of modifying their environ-                                                                                                                                                                                                           cycling. Two other articles look at community im-
                                                                              ment is unmatched by any other living organism                                                                                                                                                                                                            pacts of invasive species on taxa that have tended 
                                                                              on earth. One would be hard pressed to find today                                                                                                                                                                                                         to receive less attention than plants, namely soil 
                                                                              any environment in which human agency has not                                                                                                                                                                                                             mycorrhizae (Shah et al.), and birds (Aravind et 
                                                                              had a direct, indirect, or inadvertent impact,  al.). Finally, Rashid & Reshi, and Raizada & 
                                                                              whether through land use and land cover change,                                                                                                                                                                                                           Raghubanshi both investigated aspects of invasive 
                                                                              via the introduction of alien species, or due to                                                                                                                                                                                                          species biology that have relevance to mana-
                                                                              industrialization and the alteration of biogeo-                                                                                                                                                                                                           gement. It is telling that three of the five articles 
                                                                              chemical cycles. The introduction of alien species is                                                                                                                                                                                                     (Aravind  et al., Raizada & Raghubanshi, and 
                                                                              one aspect of human agency that is dealt with in                                                                                                                                                                                                          Sharma & Raghubanshi) focus on Lantana 
                                                                              the collection of articles that follows. The other                                                                                                                                                                                                        camara, perhaps the most ubiquitous and cons-
                                                                              aspect of human agency dealt with in this  picuous invasive alien plant across much of 
                                                                              collection of articles is a byproduct of industria-                                                                                                                                                                                                       tropical and subtropical India. The other two 
                                                                              lization, namely environmental pollution.                                                                                                                                                                                                                 articles (Rashid & Reshi, and Shah et al.) deal 
                                                                                                 Invasions by alien species perhaps first  with invasive species in temperate Kashmir, a 
                                                                              captured the imagination of ecologists as a result                                                                                                                                                                                                        region that is biogeographically quite distinct from 
                                                                              of Elton’s (1958) very prescient book, but it is                                                                                                                                                                                                          the rest of the country. We hope the collection of 
                                                                              really only in the last few decades that the effects                                                                                                                                                                                                      articles featured here is merely the tip of the 
                                                                                                                                                                                                                                                                                       – have                                           iceberg, with much more yet to come.  
                                                                              of alien species invasions – long entrained                                                                                                                                                                                                                                 Rapid technological, industrial and agri-
                                                                              really become manifest. In fact, the International                                                                                                                                                                                                        cultural advancement, coupled with increases in 
                                                                              Convention on Biological Diversity, in 2000,  population growth, has triggered the deterioration 
                                                                              declared alien invasive species to be the second                                                                                                                                                                                                          of environmental quality throughout the world. 
                                                                              greatest threat to biodiversity after habitat frag-                                                                                                                                                                                                       Rapidly growing cities, more traffic on roads, 
                                                                              mentation. Yet, despite the increasing inter-                                                                                                                                                                                                             growing energy consumption and waste produ-
                                                                              national focus on invasive alien species, there was                                                                                                                                                                                                       ction, and lack of strict implementation of environ-
                                                                              very little attention paid to them in India till only                                                                                                                                                                                                     mental regulation are increasing the discharge of 
                                                                              a few years ago. The first national workshop on                                                                                                                                                                                                           pollutants into air, water, and soil (Agrawal 2005; 
                                                                              invasive alien species in India was held as recently                                                                                                                                                                                                      Sharma et al. 2009). The future development of 
                                                                              as 2004 (Raghubanshi et al. 2005), and was, in                                                                                                                                                                                                            most tropical countries is likely to only further 
                                                                              many ways, a call to action.                                                                                                                                                                                                                              aggravate the pollution problem. Environmental 
                                                                                                The collection of articles featured here, though                                                                                                                                                                                        pollution not only causes unprecedented misery to 
                                                                              small, nonetheless manages to capture a number                                                                                                                                                                                                            human beings, but it also has negative effects on 
                                                                              of the issues surrounding invasive species that are                                                                                                                                                                                                       managed as well as natural ecosystems. Policies to 
                                                                              of interest to ecologists. Sharma & Raghubanshi                                                                                                                                                                                                           reduce emissions are often costly to implement, 
                                                                              investigated the effects of habitat fragmentation                                                                                                                                                                                                         and need to be balanced against a range of other 
                                                                              on ecosystem invasibility. They also report the 
                                                                               
                                                                              *
                                                                                  Corresponding Author; e-mail: hiremath@atree.org; madhoo58@yahoo.com 
                  304                       PLANT INVASION AND ENVIRONMENTAL POLLUTION 
                  economic and social priorities. The links between       the other on environmental pollution, during the 
                  environmental quality and plants are important          Tropical Ecology Congress held in Dehradun in 
                  for agriculture, horticulture, and forestry. Under-     December 2007. The Congress was jointly spon-
                  standing these links is especially important for        sored by the International Society for Tropical 
                  management practices to sustain productivity under      Ecology and H.N.B. Garhwal University. The the-
                  the threat of environmental pollution.                  mes, recommendations, and broad outcome of the 
                      The articles under the section on environ-          Congress are included in Singh et al. (2009), and 
                  mental pollution cover a wide range of topics from      the first two special issues on biodiversity and 
                  the impact of ambient air pollution on plants, to       remote sensing have already been published 
                  food chain contamination, biomonitoring of heavy        (Kushwaha et al. 2010; Rawat 2009). The Guest 
                  metals, and bioremediation. Tiwari et al. investi-      Editors express their gratitude to the Organizers 
                  gated the impact of ambient air pollutants on a         of the Tropical Ecology Congress for the financial 
                  vegetable crop using open-top chambers installed        support to organize the session and to the 
                  in a suburban area of a medium-sized city. They         International Society for Tropical Ecology  for 
                  documented seasonal variations in plant adapta-         publishing this issue. 
                  tions to air pollutants. Mid-stream surface-water                          References 
                  contamination in the river Ganga, at Varanasi, by 
                  atmospheric deposition of heavy metals has been         Agrawal, M. 2005. Effects of air pollution on agriculture: 
                  reported by Pandey et al., Singh et al. demonstrated        An issue of national concern. National Academy 
                  that the use of waste water from a sewage                   Science Letter 28: 93-106. 
                  treatment plant contaminates soil and vegetables,       Elton, C.S. 1958. The Ecology of Invasions by Animals 
                  with serious implications for human health.                 and Plants. Methuen, London, UK. 
                  Sharma & Agrawal have shown that zinc acts              Kushwaha, S.P.S., V.K. Dadhwal & Skip J. Van Bloem. 
                  antagonistically on the uptake of cadmium, a non-           2010. Remote sensing of tropical ecosystems. 
                  essential heavy metal. Hence, zinc could be used at         Tropical Ecology 51: 1-2. 
                  cadmium-contaminated sites to reduce its negative       Raghubanshi, A.S., L. C. Rai, J.P. Gaur & J.S. Singh. 
                  effects. Pandey & Upadhyay have suggested the               2005. Alien invasive species and biodiversity in 
                  use of Pseudomonas fluorescence for bioremedia-             India. Current Science 88: 539-540. 
                  tion of Direct Orange-102, a dye used in the textile    Rawat, G.S. 2009. Current trends in tropical biodiversity 
                  industry. Anita Singh was given the Alice J.                research and conservation. Tropical Ecology 50: 5-6. 
                  Murphy Outstanding Achievement Award for her            Singh. S.P., S. J. Van Bloem & A.R. Nautiyal (Series 
                  paper on “Risk assessment of heavy metal toxicity           Editors). 2009. Papers from Tropical Ecology 
                  through contaminated vegetables from waste water            Congress. Tropical Ecology 50: 1-3. 
                  irrigated area”.                                        Sharma, R.K., M. Agrawal & F.M. Marshall.  2009. 
                      This special issue of Tropical Ecology is               Heavy metals in vegetables collected from 
                  composed of selected papers presented during two            production and market sites of a tropical urban area 
                  special sessions, one on invasive alien species,  and       in India. Food and Chemical Toxicology 47: 583-591.