Effects Of Soil Moisture And PH On Cadmium Accumulation And Growth In Cucumber And Chinese Cabbage Under Cadmium Contamination

With the development of science and technology,the harm brought by cadmium pollution is getting worse day by day.People’s food safety is also under great threat.The first problem is the safety of agricultural products.Severe cadmium pollution also affects the growth of vegetables and endangers human health.Previous investigations have found that different regions,different vegetable species,different environmental conditions and different agronomic measures all have impacts on cadmium pollution.Among various influencing factors,the research on soil moisture and pH in cadmium pollution is not comprehensive enough,so how to reduce the accumulation of cadmium in plants through water and pH regulation technology needs further exploration.In addition,due to the difference of cadmium accumulation rules caused by different edible parts of vegetables,in this experiment,cucumber edible fruits and whole plant edible Chinese cabbage were used as test materials,under the condition of simulating cadmium contaminated soil,the morphological changes of soil moisture and pH on exchangeable state and carbonate binding state of soil cadmium were studied,and the relationship betwee n soil moisture and pH interaction on cadmium accumulation and growth of cucumber and Chinese cabbage was analyzed through the determination of cadmium content and related physiological changes in plants,providing theoretical and data support for further research on cadmium accumulation and production of cucumber and Chinese cabbage under cadmium pollution.The following conclusions were drawn from the tests:soil moisture and pH have no significant effect on the total amount of cadmium in soil.soil moisture deficit(50%-65%WHC)increases exchangeable cadmium content and decreases carbonate bound cadmium content.Excessive soil moisture(80%-95%WHC)reduces exchangeable cadmium content and increases carbonate bound cadmium content.When the soil pH is 5-6,the exchangeable cadmium content is increased and the carbonate bound cadmium content is reduced.When the soil pH is 7-8,the exchangeable cadmium content is reduced and the carbonate bound cadmium content is increased.The difference is more significant with the extension of treatment time.Cadmium pollution has a toxic effect on cucumber and Chinese cabbage plants,which is manifested in the inhibition of cucumber and Chinese cabbage growth,inhibition of photosynthesis and reduction of yield and quality.Excessive soil moisture(80%-95%WHC)reduces the toxic effect of cadmium pollution on cucumber and Chinese cabbage plants,is beneficial to the growth of cucumber and Chinese cabbage,improves the yield and quality of cucumber and Chinese cabbage,and is beneficial to the safe production of cucumber and Chinese cabbage.Cadmium accumulation in cucumber and Chinese cabbage was as follows: cucumber: root > leaf > fruit,Chinese cabbage: root > leaf.The difference of cadmium accumulation in the same part of cucumber and Chinese cabbage is as follows: the cadmium accumulation in Chinese cabbage leaves is significantly higher than that in cucumber leaves,and the cadmium accumulation in cucumber roots is slightly lower than that in Chinese cabbage.The effects of soil moisture on cadmium accumulation in cucumber and Chinese cabbage are as follows: soil moisture deficit(50%-65%WHC)increases cadmium accumulation in cucumber and Chinese cabbage plants;Excessive soil moisture(80%-95%WHC)reduced cadmium accumulation in cucumber and Chinese cabbage plants.The interaction between soil moisture and pH affected cucumber and Chinese cabbage under different concentrations of cadmium pollution,as follows: with the increase of cadmium concentration,the more cadmium accumulated in the plant,the more serious the growth restriction of the plant,and the yield decreased significantly;The combined action of soil moisture 80%-95%WHC and pH7-8 can alleviate the toxicity of cadmium pollution to plants,reduce cadmium accumulation in cucumber and Chinese cabbage plants,promote the growth of cucumber and Chinese cabbage,and improve their yield and quality.