How Himalayan communities are changing cultivation practices in the context of climate change

Climate change can have significant impacts on crop yields and food security.This study assessed the linkages between climate change and crop yields to obtain a better understanding on the drivers of food security.The study was conducted in Pasagaun village of Lamjung District in Nepal,where household surveys and focus group discussions(FGDs)were used to collect data including crop cultivation,irrigation facilities,and adaptation strategies.Moreover,climate data(temperature and precipitation)from 1992 to 2020 were collected from the Khudi Bazar meteorological station and crop yield data were obtained from the Agri-Business Promotion and Statistics Division.Trend analysis of temperature and precipitation was conducted using MannKendall trend test and Sen’s slope method,and the results showed an increase in the average temperature of approximately 0.02℃/a and a decrease in the annual precipitation of 9.84 mm/a.The cultivation of traditional varieties of rice and foxtail millet(Kaguno)has vanished.Although,there was no significant impact of the maximum temperature on the yield of rice and maize,the regression analysis revealed that there are negative relationships between rice yield and annual minimum temperature(r=-0.44),between millet yield and annual precipitation(r=-0.30),and between maize yield and annual minimum temperature(r=-0.31),as well as positive relationship between rice yield and annual precipitation(r=0.16).Moreover,average rice yield and millet yield have decreased by 27.0% and 57.0% in 2000-2020,respectively.Despite other reasons for the decrease in crop yield such as the lack of irrigation facilities,out-migration of farmer,and increased pest infestation,respondents have adopted adaptation strategies(for example,shifts in cultivation time and changes in crop types)to minimize the impacts of climate change.More investigation and community-based farming education are needed to understand and alleviate the harmful impacts of climate change on crop yield,as effective adaptation coping strategies are still insufficient.This study provides insights into the adaptation strategies that are necessary to keep food security in the face of climate change.

Trace Metal Elements (Pb, Cd and As), 15N Nitrogen and Phosphorus Isotopes Accumulation in Three Varieties of Tomato from Conventional and Agro-Ecological Farming Systems in Burkina Faso

Tomato is a market gardening product that plays an important nutritional and economic role in Burkina Faso. However, the bad use of pesticides for its production could have negative impacts consumers’ health. The objective of the present study was to assess the concentration of trace metal elements (Pb, Cd and As), 15N isotopes (NO2-, NO3-, NH4+) and phosphorus (PO42-) in tomatoes according to cultivation practices. Thus, three tomato varieties (Mongal F1, F1 Cobra 26 and Roma F1) were grown using organic and conventional production methods on 2 sites at Nongr Massom, (commune of Kadiogo province). The trace metal elements were analyzed using atomic absorption spectrophotometry, the isotopes 15N (NO2-, NO3-, NH4+) and phosphorus (PO43-) using standardized methods. Tomatoes from conventional agriculture had higher levels of trace metal elements (0.163 - 0.298 mg/Kg, 0.082 - 0.146 mg/Kg and 0.018 - 0.032 mg/Kg respectively for Pb, Cd and As) than those from organic agriculture samples. Concentration of trace metal is lower for organic production with a reduction of 19.02%, 19.69% and 20.77% for Pb, Cd and As respectively compared to conventional production. High levels were recorded for the Roma F1 variety. The concentrations of trace metal elements in organic production are lower than the codex standards (2010) while those in conventional production are higher. These results could be due to the use of chemical inputs that could have a negative impact on the nutritional quality of these tomatoes. The concentration of trace metal elements in tomato fruits is strongly correlated by production method and less by the variety (genetic).

Cropland physical disturbance intensity： plot-scale measurement and its application for soil erosion reduction in mountainous areas

Various kinds of human disturbances on cropland are the main reasons for soil erosion and land degradation.Farming practices in mountainous areas vary greatly among cropland plots because of the heterogeneity of biophysical conditions and differences in farmers'management behavior.The main purpose of this paper is to develop a composite index of cropland physical disturbance intensity(CLDI)to reflect the plot-scale discrepancy of potential soil erosion in mountainous areas.The study was based on both plot survey and household interview data,collected from six typical catchments in mountainous areas of southwestern China.Four kinds of physical disturbance practices and two kinds of conservation practices during one crop rotation period were synthesized to develop the CLDI index.The rough set theory was referenced to avoid subjectivity during weight allocation.The results show that conventional tillage,deep fertilization,and manual weeding are the main causes of cropland soil erosion,whereas manure application in combination with seasonal fallow reduces soil erosion.Different crop types as well as cropland location factors determine the spatial pattern of CLDI.Crop rotation modes with major crops of tobacco and maize resulted in a maximal CLDI,and cropland plots with a distance radius of 150 meters away from households received the most intensive physical disturbance.These results are critical to help better protect rural environments in mountainous areas.Based on the results,methods to reduce cropland soil erosion are suggested.

The Digital Agricultural Knowledge and Information System(DAKIS):Employing digitalisation to encourage diversified and multifunctional agricultural systems

Multifunctional and diversified agriculture can address diverging pressures and demands by simultaneously enhancing productivity,biodiversity,and the provision of ecosystem services.The use of digital technologies can support this by designing and managing resource-efficient and context-specific agricultural systems.We present the Digital Agricultural Knowledge and Information System(DAKIS)to demonstrate an approach that employs digital technologies to enable decision-making towards diversified and sustainable agriculture.To develop the DAKIS,we specified,together with stakeholders,requirements for a knowledge-based decision-support tool and reviewed the literature to identify limitations in the current generation of tools.The results of the review point towards recurring challenges regarding the consideration of ecosystem services and biodiversity,the capacity to foster communication and cooperation between farmers and other actors,and the ability to link multiple spatiotemporal scales and sustainability levels.To overcome these challenges,the DAKIS provides a digital platform to support farmers'decision-making on land use and management via an integrative spatiotemporally explicit approach that analyses a wide range of data from various sources.The approach integrates remote and in situ sensors,artificial intelligence,modelling,stakeholder-stated demand for biodiversity and ecosystem services,and participatory sustainability impact assessment to address the diverse drivers affecting agricultural land use and management design,including natural and agronomic factors,economic and policy considerations,and socio-cultural preferences and settings.Ultimately,the DAKIS embeds the consideration of ecosystem services,biodiversity,and sustainability into farmers'decision-making and enables learning and progress towards site-adapted small-scale multifunctional and diversified agriculture while simultaneously supporting farmers'objectives and societal demands.

Heavy Metal Contamination of Agricultural Soils in Taiyuan, China

To evaluate the current state of the environmental quality of agricultural soils in Taiyuan City, a hotspot for China's industrial development, the concentrations of 8 heavy metals in soils were investigated by means of extensive sampling in farmlands, forestlands,and grasslands in the city. Statistical analyses and spatial distribution maps were used to identify the most significant heavy metal pollutants. The mean concentrations of As, Cd, Cu, Hg, Pb, Zn, Ni, and Cr were slightly higher than their background values in Taiyuan's topsoil, but were lower than the maximum permissible concentrations in the Chinese Environmental Quality Standard for agricultural soils. Farmland soils in Taiyuan had the highest average Cd, Cu, Hg, Pb, Zn, and Cr concentrations, but the As and Ni concentrations did not differ significantly among the farmland, forestland, and grasslands. Soil contamination by Cd, Cu, Hg, Pb,Zn, and Cr was mainly derived from farming practices, especially the use of sewage water for irrigation. In contrast, As and Ni might derive mainly from the soil parent material. The identification of heavy metal sources in agricultural soils may provide a basis for taking appropriate action to protect soil quality.

Changes in ecosystem service values strongly influenced by human activities in contrasting agro-ecological environments

Background:Evaluating the impacts of land-use/land-cover(LULC)changes on ecosystem service values(ESVs)is essential for sustainable use and management of ecosystems.In this study,we evaluated the impact of human activity driven LULC changes on ESVs over the period 1982–2016/17 in contrasting agro-ecological environments:Guder(highland),Aba Gerima(midland),and Debatie(lowland)watersheds of the Upper Blue Nile basin,Ethiopia.Results:During the study period,the continuous expansion of cultivated land at the expense of natural vegetation(bushland,forest,and grazing land)severely reduced the total ESV by about US$58 thousand(35%)in Aba Gerima and US$31 thousand(29%)in Debatie watersheds.In contrast,the unprecedented expansion of plantations,mainly through the planting of Acacia decurrens,led,from 2006,to a ESV rebound by about US$71 thousand(54%)in Guder watershed,after it had decreased by about US$61 thousand(32%)between 1982 and 2006.The reduction in natural forest area was the major contributor to the loss of total ESV in the study watersheds,ranging from US$31 thousand(63%)in Debatie to US$96.9 thousand(70%)in Guder between 1982 and 2016/17.On an areaspecific basis,LULC changes reduced the average ESV from US$560 ha^(−1) year^(−1)(1982)in Guder to US$306 ha^(−1) year^(−1)(2017)in Debatie watersheds.Specific ESVs such as provisioning(mainly as food production)and regulating services(mainly as erosion control and climate regulation)accounted for most of the total ESVs estimated for the study watersheds.Conclusions:In most cases,the total and specific ESVs of the watersheds were negatively associated with the population growth,which in turn was positively associated with the expansion of cultivated land over the study period.In Guder,however,ESVs were positively associated with population growth,especially after 2012.This is mainly due to the expansion of Acacia decurrens plantations.Our results suggest,therefore,that future policy measures and directions should focus on improving vegetation cover through planting multipurpose trees such as Acacia decurrens to prevent future loss of ESV in the midland and lowland regions of the Upper Blue Nile basin and beyond.However,caution must be taken during plantation of invasive species as they may have undesirable consequences.