My bonzai tree is shedding dead leaves and leaves are turning yellow...what does this mean? is it dieing?

Any decidious bonsai tree will drop its leaves and regrow them, just like any other decidious tree. Most bonsais are actually supposed to be kept outside the majority of the time so they can stay in synch with their natural cycles--just like regular trees planted in the ground. Unless your bonsai is a tropical plant and you live in a temperate zone, you should have it outside (but protected) all year round, only bringing it inside occasionally for decorative purposes. Most bonsais will not thrive indoors--it's too dry, there's not enough light, and it disturbs their natural cycles. There are many good books on caring for bonsais. You should get a hold of one if you are serious about keeping yours healthy.

genuinely a Deciduous leaf encompasses a blade and a stalk or petiole. on the backside of the petiole is a skinny layer of cells referred to as The Abscission layer. in the time of the summer chlorophyll interior the leaf, below the effect of temperature, gentle and water, manufacture sugars, utilized by making use of the tree as nutrition for enhance. interior the iciness the situations are no longer constructive for the provision of nutrition and the tree 'hibernates'. As situations visit pot in the time of the fall the leaves close down by making use of laying down a layer of cork interior the abscission layer, battling communique between the leaf and the physique of the tree. This precipitates the close down of the tree. Sugars trapped interior the leaves are grew to become into the yellows, reds and browns that we understand as Autumn colorings. With warmer winters besides the undeniable fact that the sunshine is plenty from ideal the exchange has dragged on in the time of the iciness. Leaf laying off has taken plenty longer.

it is a combo of overwatering and lack of food...give it some food /change the soil or just a plant food.