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Soil erosion by water has a debilitating effect on crop productivity. Though limited and scattered data is available on loss of production due to water erosion in India, no systematic effort has been made to compute the losses in crop production based upon experimental data, major soil groups, and prevailing erosion rates. The objective of this study is to estimate on-site physical and economic loss of production of major cereal, oilseed, and pulse crops cultivated on rainfed areas of India due to soil erosion by water. The estimation is done by integrating the available experimental data of a crop with the rainfed area of that crop under each erosion intensity category for each of the three major soil groups (alluvial, black and red) in a given state. Following this approach, the total production loss due to water erosion of rainfed areas under major cereal, oilseed, and pulse crops in India was observed to occur at 16%, which in actual physical terms was estimated as 13.4 million t (13.2 million tn) and in economic terms as $2.51 billion (INR 111.3 billion) (the conversion has been given in US dollars as per average conversion rate of 2005 to 2006, i.e., at INR 44.273 per US dollar). Among the six zones of India, the average production loss occurred within a range of 10% (northern) to 24% (southern). At state level, the production loss ranged from 1.4% in Punjab and Haryana states located in alluvial Indo-Gangetic Plains to 41% in the erosion-prone northeastern Himalayan state of Nagaland. In terms of production loss among major groups of crops, cereals contributed 66% to the total loss, followed by oilseeds (21%) and pulses (13%). A similar trend was observed for the monetary losses amounting to 45% for cereals, 33% for oilseeds, and 22% for pulses. Paddy was the most affected among all the crops in terms of both production (4.3 million t [4.23 million tn]) and monetary ($0.56 billion [INR 24.4 billion]) losses. Since the losses are cumulative over time, it is imperative to undertake appropriate soil and water conservation measures for rehabilitation of rainfed areas to prevent huge declines in their productivity levels, which may escalate further due to population pressures.

Despite years of study and substantial investment in remediation and prevention, soil erosion continues to be a major environmental problem with regard to land use in India and elsewhere around the world. Furthermore, changing climate and/or weather patterns are exacerbating the problem. Our objective was to review past and current soil conservation programmes in India to better understand how production-, environmental-, social-, economic-and policy-related issues have affected soil and water conservation and the incentives needed to address the most critical problems. We found that to achieve success in soil and water conservation policies, institutions and operations must be co-ordinated using a holistic approach. Watershed programmes have been shown to be one of the most effective strategies for bringing socio-economic change to different parts of India. Within both dryland and rainfed areas, watershed management has quietly revolutionized agriculture by aligning various sectors through technological soil and water conservation interventions and land-use diversification. Significant results associated with various watershed-scale soil and water conservation programmes and interventions that were effective for reducing land degradation and improving productivity in different parts of the country are discussed.

Due to extensive root system, connected rhizome bamboos are considered suitable for improving soil properties within a short period, though most of the claims are anecdotal and need to be supported with quantified data. The study evaluates seven bamboo species viz., Bambusa balcooa, Bambusa bambos, Bambusa vulgaris, Bambusa nutans, Dendrocalamus hamiltonii, Dendrocalamus stocksii and Dendrocalamus strictus for their rooting pattern and impact on soil health properties. Coarse and fine root intensity was maximum in B. vulgaris. Coarse root biomass ranged from 0.6 kg m −3 in B. nutans to 2.0 kg m −3 in B. vulgaris and B. bambos. Fine root biomass ranged from 1.1 kg m −3 in B. nutans to 4.5 kg m −3 in D. hamiltonii. Contribution of fine roots in terms of intensity and biomass was much higher than coarse roots. Fine root biomass showed declining trend with increase in soil depth in all the species. During sixth year, the litter fall ranged from 8.1 Mg ha −1 in D. stocksii to 12.4 Mg ha −1 in D. hamiltonii. Among soil physical properties significant improvement were recorded in hydraulic conductivity, water stable aggregates and mean weight diameter. Soil pH, organic carbon and available phosphorus under different species did not reveal any significant changes, while significant reduction was observed in total nitrogen and potassium. Significant positive correlation was observed between WSA and iron content. Soil microbial population and enzyme activities were higher in control plot. Considering root distribution, biomass, soil hydraulic conductivity and water stable aggregates, B. bambos, B. vulgaris and D. hamiltonii are recommended for rehabilitation of degraded lands prone to soil erosion. Bamboo grows worldwide in at least 37 million ha and covers 3.2 percent of forest areas of their host countries, or about 1 percent of the global forest area 1. Bamboo being an annual yielding crop with multipurpose utility has proven potential for contributing to poverty reduction, environmental protection and achievement of United Nations Sustainable Development Goals-SDG1, SDG7, SDG 11, SDG 12, SDG 13, SDG 15, and SDG 17 2. Many countries are now exploring options for achieving land degradation neutrality through the use of bamboo. Bamboo also contributes to the Bonn Challenge, the global initiative targeting the restoration of 200 million hectares of the planet's degraded lands, to which International Bamboo and Rattan Organization (INBAR) member states have agreed to contribute about five million hectares of bamboo plantations 3. India is the second richest country of the world, after China, in terms of bamboo genetic resources 4. The bamboo area of the country is estimated to be 15.69 million hectare with total standing stock of 189 million tons 5. Raising of bamboo on degraded soils improves soil quality and sequesters carbon in the soil 6,7. Bamboo due to its fast growth and extensive root system improves soil physical, chemical and biological properties; controls soil erosion; filters sediment and is considered suitable...