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3D point cloud analysis of imagery collected by unmanned aerial vehicles (UAV) has been shown to be a valuable tool for estimation of crop phenotypic traits, such as plant height, in several species. Spatial information about these phenotypic traits can be used to derive information about other important crop characteristics, like fresh biomass yield, which could not be derived directly from the point clouds. Previous approaches have often only considered single date measurements using a single point cloud derived metric for the respective trait. Furthermore, most of the studies focused on plant species with a homogenous canopy surface. The aim of this study was to assess the applicability of UAV imagery for capturing crop height information of three vegetables (crops eggplant, tomato, and cabbage) with a complex vegetation canopy surface during a complete crop growth cycle to infer biomass. Additionally, the effect of crop development stage on the relationship between estimated crop height and field measured crop height was examined. Our study was conducted in an experimental layout at the University of Agricultural Science in Bengaluru, India. For all the crops, the crop height and the biomass was measured at five dates during one crop growth cycle between February and May 2017 (average crop height was 42.5, 35.5, and 16.0 cm for eggplant, tomato, and cabbage). Using a structure from motion approach, a 3D point cloud was created for each crop and sampling date. In total, 14 crop height metrics were extracted from the point clouds. Machine learning methods were used to create prediction models for vegetable crop height. The study demonstrates that the monitoring of crop height using an UAV during an entire growing period results in detailed and precise estimates of crop height and biomass for all three crops (R 2 ranging from 0.87 to 0.97, bias ranging from −0.66 to 0.45 cm). The effect of crop development stage on the predicted crop height was found to be substantial (e.g., median deviation increased from 1% to 20% for eggplant) influencing the strength and consistency of the relationship between point cloud metrics and crop height estimates and, thus, should be further investigated. Altogether the results of the study demonstrate that point cloud generated from UAV-based RGB imagery can be used to effectively measure vegetable crop biomass in larger areas (relative error = 17.6%, 19.7%, and 15.2% for eggplant, tomato, and cabbage, respectively) with a similar accuracy as biomass prediction models based on measured crop height (relative error = 21.6, 18.8, and 15.2 for eggplant, tomato, and cabbage).

Conflicts between local people and protected area managers are a common problem in developing countries, but in many cases there has been little attempt to comprehensively characterize the underlying problems. Resource uses, management practices, economy and people's perceptions of problems and likely solutions were analysed in two villages near and two villages away from the core zone of Nanda Devi Biosphere Reserve in the Indian Himalaya. Agriculture, although practised on less than 1% of the area, was the primary occupation of local people. Six annual crops of a total of 22 and all four horticultural crops on private farms were damaged by wildlife, but Reserve management provided compensation only for livestock killing by wildlife and compensation amounted to only 4–10% of the total assessed monetary value of killed livestock. A variety of wild plant products were used locally but 27 were marketed by more than 50% of surveyed families; income from wild products was substantially lower than that from crops and livestock. A sociocultural change from a subsistence to a market economy, together with changes in traditional land/resource rights and institutions, has led to a number of changes in land-use and management practices. The livestock population has declined, agricultural area has remained the same and people have started cultivating medicinal species in the last 20 years. These changes seem complementary to the goal of conservation. However, changes such as abandonment of some traditional food crops and stress on cash crops lacking fodder value, requiring substantial manure inputs derived from forest litter and livestock excreta, and causing severe soil erosion, seem to counter the goal of environmental conservation. Some government-managed Reserve Forest sites were similar to the Community Forests in terms of species richness, basal area and soil physico-chemical properties. Two Reserve Forest sites showed basal areas of 160.5–191.5 m2/ha, exceeding the highest values reported so far from the region. The formal institutional framework of resource management seems to be not as effective as the traditional informal system. The Reserve Management Plan lays more emphasis on legal protection than on the sustainable livelihood of local communities and has led to conflicts between local people and reserve managers. Plantation of fodder and medicinal species in degraded forest lands, suppression of economic exploitation of local people in the market, enhancement of local knowledge of the economic potential of biodiversity, incentives for cultivation of crops with comparative advantages and lesser risks of damage by wildlife, and rejuvenation of the traditional involvement of the whole village community in decison-making, could be the options for resolving conflicts between people and protected areas in this case.

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India has the second largest population in the world and is characterized by a broad diversity in climate, topography, flora, fauna, land use, and socioeconomic conditions. To help ensure food security in the future, agricultural systems will have to respond to global change drivers such as population growth, changing dietary habits, and climate change. However, alterations of how food is produced in the future may conflict with other UN Sustainable Development Goals (SDGs), such as the protection of land resources and climate change mitigation. It is crucial for decision‐makers to understand potential trade‐offs between these goals to find a balance of human needs and environmental impacts. In this paper, we analyze pathways of agricultural productivity, land use, and land‐cover changes in India until 2030 and their impacts on terrestrial biodiversity and carbon storage. The results show that in order to meet future food production demands, agricultural lands are likely to expand, and existing farmlands need to be intensified. However, both processes will result in biodiversity losses. At the same time, the projections reveal carbon stock increases due to intensification processes and decreases due to conversions of natural land into agriculture. On balance, we find that carbon stocks increase with the scenarios of future agricultural productivity as modeled here. In conclusion, we regard further agricultural intensification as a crucial element to help ensure food security and to slow down the expansion of cropland and pasture. At the same time, policies are required to implement this intensification in a way that minimizes biodiversity losses.