地理漫步·世界地理英语30篇（1）
25 / 30
正在校验访问权限...
Ganges Delta Floodplain Farming and Silt Enrichment
恒河三角洲洪泛农业与淤泥富集
-
The Ganges Delta spans Bangladesh and eastern India, forming the world's largest active delta.
-
Annual monsoon floods deposit nutrient-rich silt across vast low-lying farmlands each year.
-
Farmers time rice planting to coincide with receding floodwaters and fresh sediment layers.
-
This natural fertilization reduces dependence on synthetic inputs while sustaining high yields.
-
However, embankments and upstream dams increasingly disrupt the flood pulse and sediment supply.
-
Salinity intrusion during dry seasons also threatens soil fertility in southern delta zones.
-
Floating gardens, built on water hyacinth rafts, offer adaptive cultivation where land is seasonally submerged.
-
Tidal channels and mangrove belts buffer storm surges but shrink under aquaculture pressure.
-
Delta subsidence and sea-level rise compound flood risks for over 150 million residents.
-
Sustainable management must balance rice production, fisheries, and wetland conservation.