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Để nghiên cứu độc tính của chì trong điều kiện đất ngập nước như những người Steele của thành phố Bay, 129 Microcosms đã được thực hiện, mỗi một cây giống của cây bách hoặc đầm lầy kẹo cao su màu đen (hình 7.1; Phụ lục Bảng A7.1). Mô hình thu nhỏ là một hệ sinh thái nhỏ đang phát triển trong một container. trong thí nghiệm vật liệu than bùn và một hạt giống của cuộc sống từ đầm lầy ngoài trời được đặt trong mỗi container và được phát triển trong 2 tháng. Mỗi mô hình thu nhỏ đã có một muỗng. | CHAPTER 7 Experiments with Lead and Acid in Wetland Microcosms Shanshin Ton In order to study the toxicity of lead in wetland conditions like those of the Steele City Bay 129 microcosms were made each with a seedling of cypress or swamp black gum Figure 7.1 Appendix Table A7.1 . A microcosm is a small ecosystem developing in a container. In this experiment peaty materials and a seeding of life from the outdoor swamp were placed in each container and allowed to develop for 2 months. Each microcosm had a teaspoon of fertilizer nutrients placed under the root zone. Seedlings were added and the microcosms were arranged at random in a greenhouse. Arrangements were made for chemical solutions containing lead and acid in different concentrations to drip into these containers Figure 7.1 . In this way some conditions in the Sapp swamp were duplicated. All microcosms received similar quantities of water so that the effect of water on growth was made uniform. Microcosms were not crowded together so that there was abundant natural light. Height of seedlings was measured and related to the treatments. Lead concentrations applied were 0.5 and 1.0 pg ml a microgram per milliliter pg ml is the same as a gram per cubic meter g m3 . Solutions with zero lead were also applied. A comparison without special treatment is called a control. Because some growths developed in the tubes delivering the waters with lead the concentrations actually reaching the microcosms when analyzed were found to be somewhat less than the intended concentration. See Appendix Table A7.2. Acidity like that in the Steele City Bay was duplicated in microcosm by adding sulfuric acid to the dripping waters. pH is the scale of acidity concentration of hydrogen ions on a logarithmic scale the lower the value the more acid pH 4 is ten times more acid than pH 5 . Treatment waters dripping into microcosms for 8 months included pH 2 4 and the neutral pH 7. Neutral pH is neither acid nor basic and was included for .
