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1.
Many experts agree that more agricultural investment is needed in the global South to improve local food security and reduce poverty. However, there is a lack of consensus about the types of investment needed to achieve these goals. This paper contributes to the literature on large agricultural investments and corresponding business models by inventorying and analysing such investments in Kenya’s Nanyuki area. We identify four clusters of business models that differ primarily by type of production and other distinct determinants, namely: demand from markets; access to land; land tenure regime and colonial history; actors involved; biophysical context; labour availability; and governance of the value chain via private standards. The study results shed light on the factors that help or hinder implementation of large agricultural investments and shape their impacts in the context of African land use systems. The way land is accessed represents one of the most-decisive factors determining the risks and opportunities associated with such projects. We find that most investments in the Nanyuki area occur on land bought or leased from private owners.  相似文献   
2.
Shark-diving tourism provides important economic benefits to the Maldives. We examine the link between shark conservation actions and economic returns from diving tourism. A combined travel cost and contingent behaviour approach is used to estimate the dive trip demand under different management scenarios. Our results show that increasing shark populations could increase dive-trip demand by 15%, raising dive tourists’ welfare by US$58 million annually. This could result in annual economic benefits for the dive-tourism industry of >US$6 million. Conversely, in scenarios where shark populations decline, where dive tourists observe illegal fishing, or if dive operators lack engagement in shark conservation, dive trip demand could decrease by up to 56%. This decline causes economic losses of more than US$24 million annually to the dive tourism industry. These results highlight the dependence of the shark-diving industry on the creation and enforcement of appropriate management regimes for shark conservation.  相似文献   
3.
Urban commuting has continuously fascinated scholars and decision-makers. As few people live and work in the same place, there is always excess commuting (i.e., the non-optimal or surplus work travel occurring in cities because people do not minimize their journeys to work for most residents). Traditional commuting data sources (e.g., questionnaires and census surveys) are challenged by small samples, high cost, and low spatiotemporal resolution. In contrast, the big social-sensing data (e.g., smart card and mobile phone data) only consider one or two traffic mode of a route, which is not consistent with the real-life condition. This article proposes a framework for modeling excess commuting based on open-source data of the ten most populous megacities in China. We downloaded residential points of interest (POIs) from Lianjia Real Estate website and obtained workplace POIs from China's AMAP, which is widespread used as Google map. The stratified sampling approach was employed to derive commuting pairs. Both commuting distance and time were obtained by the shortest path under public transportation from AMAP. Then, the linear programming method was employed to calculate the theoretical minimum commuting time and distance of each city. We analyzed the statistical property and spatial distributions of excess commuting and found that (1) commuting distances and time (ranging from 9.1 to18.1 km and from 44.8 to 74.3  minutes) of all ten megacities follow a left-skewed normal distribution; (2) in terms of commute cost, all cities show universal core-periphery patterns where the spatial heterogeneity of the commuting time is more significant than that of distance; (3) for each city, the excess commuting measured by time (i.e. from 0.61 to 0.79) is lower than that measured by distance (i.e. 0.68 to 0.89); and (4) the role of mixing land use, waterbody distribution, and centripetal urbanization on urban commuting distance and time is significant.  相似文献   
4.
In the beginning of 2019, the Singaporean government announced its desire to increase domestic food production and, in particular, aquaculture to reach 30% of self-sufficiency by 2030. Similar policies aiming at encouraging aquaculture growth abound in high-income countries in recent years, but have had limited success. Hence, this paper investigates the potential implications of such policies to foresee consequences beforehand and improve the policy’s chances of success. Three scenarios of aquaculture development are built for Singapore until 2040, among which a business-as-usual scenario and two explorative scenarios aiming at increasing aquaculture production, the first emphasizing existing technologies and the second giving priority to novel and innovative ones, like recirculating aquaculture systems. These scenarios are assessed using an adapted version of the supply-demand partial equilibrium model Asiafish to challenge their viability in the socioeconomic context of Singapore. Only the two explorative scenarios are found to allow the Singaporean government to reach its goal in terms of seafood self-sufficiency by 2030, one of which appears to have strong advantages. In this scenario, imports decrease by 28% by 2040, seafood self-sufficiency reaches 69% and 90% of all aquaculture originates from innovative technologies, which would make Singapore an aquaculture tech-hub. It also has higher benefits within Singapore environmental, social and economic constraints such as land and aquafeed scarcity.  相似文献   
5.
6.
This paper explores the case of peripheral settlement growth in the Greater Frankfurt (Main) region within current debates on global suburbanization. Within Germany’s sophisticated spatial planning regime, Greater Frankfurt’s system of regionalized land-use planning marks an ambitious initiative to contain urban sprawl. Nonetheless, expansive peripheral settlement growth, and socio-spatial polarization remain distinct characteristics of the booming region. Analyzing state regulation vis-à-vis dynamics of capitalist urbanization and private authoritarianism, we decipher the complex governance arrangements producing this, at first sight, contradictory simultaneity. We uncover the rationales of local growth politics of autonomous municipalities and the region’s multiplied institutional fragmentation that undermine planning ambitions to contain suburban growth. We conclude by critically assessing the political economies of suburbanization in Greater Frankfurt and point to prospects for regional reform.  相似文献   
7.
Economic reform in China has resulted in rapid urbanisation over the past three decades, changing the urban and rural landscape dramatically. A large amount of farmland was developed, leading to conflict between construction demand and farmland protection. In response, the “Link Policy” was proposed in 2005 that seeks to concurrently preserve farmland while providing for urban expansion through land exchange. The effectiveness of the Link Policy has not been systematically investigated. The purpose of this study is to analyse and evaluate outcomes of the Link Policy objectives from both a participant and investigator’s interpretive perspective. Ezhou, the first experimental city to implement the Link Policy in Hubei Province in central China, was selected as a case study area. Eight different communities in Ezhou were visited and 160 semi-structured interviews were conducted with resettled rural residents in March 2016. A combination of interviews and investigator field observations were used to evaluate the Link Policy objectives. The results show that participants recognize and support improving rural living conditions and coordinating urban-rural development, but the Link Policy failed to achieve the objectives of preserving farmland, protecting farmers’ land use rights and interests, and facilitating agricultural production. Participants perceived concentrated resettlement communities to be more efficient in land use compared to more expansive rural settlements, but vacant apartments for commercial use in resettlement areas account for a large proportion of land suggesting inefficiency in the land exchanges. We suggest policy changes to achieve more successful implementation of the Link Policy.  相似文献   
8.
Effective conservation requires that conservation policies and management decisions first target local actors who are dependent on natural resource use in Protected Areas (PA) of Developing Countries (DC). In rural areas of DCs, these actors are mainly farmers who also rely on off-farm activities such as harvest of Non-Timber Forest Products (NTFPs) to complement their livelihoods. Here, we propose a novel approach to support the development of policy interventions aimed at achieving conservation goals through the sustainable development of local people in PAs of DCs. The approach consists in identifying the main Livelihood and Farming Systems (LFS) and select those that are more conservation-friendly, and that may contribute to solve conservation and development problems such as Human-wildlife conflict. Identifying the existing LFS can also help in searching for conservation-relevant improvements that can contribute to local people wellbeing, considering the existing FS as the starting point for a sustainable development strategy in PAs of DC. Data from the Niassa National Reserve (NNR), the largest PA in Mozambique, were used to develop this LFS approach. Measures of effort applied in harvesting NTFPs and in managing agricultural inputs and outputs were collected from 329 households through a structured survey. Cluster analysis was performed to identify and characterise the main LFS in the NNR. Based on the cluster results, we have identified four livelihood systems (LS): gatherers, hunters, farmers and employees; four farming systems (FS): specialized in maize, rice and sorghum, and a mixed FS. A Multinomial Logistic Model was also applied to understand the drivers of LFS choice. Livelihood systems were mainly driven by household-level socio-economic factors, while FS were driven by village-level biophysical conditions. Households who were employed and had diversified farming and off-farm activities were better off and more resilient to climate change and crop-raiding animals. Intensification appears to occur gradually but has found to be limited by rainfall availability. Based on our findings, we propose that conservation experts and policy-makers should use a LFS approach to re-frame the conservation narrative in PAs of DCs and promote the existing practices that can better protect biodiversity while improving livelihood and welfare of local people.  相似文献   
9.
In 2011, Colombia started a legal land restitution process whereby government institutions help internally displaced people (IDPs) reclaim land dispossessed after 1991 through the violent conflict involving the communist guerilla, paramilitaries and the army. The designated land courts normally covers voluntary sales at the going market price at the time of dispossession, presuming buyers took advantage of the IDPs’ need for money and their low expectations of returning from their current sites of refuge. We study the rise and fall of a commercial cassava operation that started to buy land from IDPs openly in the Montes de María region on Colombia’s Caribbean coast after peace returned in 2007. After losing several land restitution court cases, the company shifted from dairy cattle that required high investments to the less demanding, but also less productive, buffalo to minimize losses in case of future successful restitution claims. The land restitution law will probably be extended beyond the initial 2021 limit due to slow progress, thereby perpetuating the insecure property rights situation that hinders investments in agriculture.  相似文献   
10.
Land Use and Land Cover (LULC) changes have profound impacts on the functioning of (agro)ecosystems and have potential to mitigate global climate change. However, we still lack interdisciplinary methods to project future LULC scenarios at spatial scales that are relevant for local decision making and future environmental assessments. Here we apply an interdisciplinary approach to develop spatially explicit projections of LULC at a resolution of 30 × 30 m informed by historic relationships between LULC and their key drivers, within the context of the four qualitative scenarios of global shared socioeconomic pathways. We apply this methodology to a case study in the Zona da Mata, Brazil, which has a history of major LULC changes. The analysis of LULC changes from 1986 to 2015 indicates that pasture area decreased from 76 to 58 % of total area, while forest areas increased from 18 to 24 %, and coffee from 3 to 11 %. Environmental protection legislation, rural credit for smallholder farmers, and demand for agricultural and raw products were identified as main drivers of LULC changes. Projected LULC for 2045 strongly depends on the global socioeconomic pathway scenarios, and forest and coffee areas may increase substantially under strong government measures in the environmentally conscious Green Road scenario or decrease in the high consumption Rocky Road scenario. Our study shows that under the set of drivers during the past three decades reforestation can go hand in hand with increase of agricultural production, but that major and contrasting changes in LULC can be expected depending on the socioeconomic pathway that will be followed in the future. To guide this process, LULC scenarios at the local scale can inform the planning of local and regional development and forest conservation.  相似文献   
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