For my Dissertation, I am looking at either soil pollution or water pollution. I am curious about heavy metal pollution and how heavy metal pollution affects local communities and ecosystems by using proximity analysis.
Student research projects must be able to test hypotheses/answer questions with the resources available, and that includes the student's time. The topics you have raised are very general and broad. In addition, they have already attracted much study. What will you add that is new?
...I just typed into Google "heavy metal pollution and how heavy metal pollution affects local communities and ecosystems by using proximity analysis" and found multiple research results; e.g.
Atmosphere | Free Full-Text | Spatial Analysis of Heavy Metal Pollution in Road-Deposited Sediments Based on the Traffic Intensity of a Megacity (mdpi.com),
Analysis of Heavy Metal Pollution in Cultivated Land of Different Quality Grades in Yangtze River Delta of China - PMC (nih.gov),
(PDF) Heavy Metal Pollution as a Biodiversity Threat (researchgate.net),
etc. Thus, you can build up on existing knowledge. Hence, I recommend checking carefully existing literature to identify the research gap.... BR Nils
Have to be extremely careful and cognizant of both, the patent and non-patent literature before embarking on such a broad topic. Also, soil pollution will ultimately lead to water pollution as the rain storm water seeps through the soil layers and contaminates the water table. e.g., Arsenic contaminated water encountered in tube-well water applied to crop irrigation. Try articles published in "Annual Review of Agronomy". Can find it even on Google by limiting search years 1950 to 2023. If encounter large response can divide your search in to two. 1950 to 2000 and 2000 to 2023. Happy searching. You might even try "meta-analysis".