Land use policies have turned southern China into one of the most intensively managed forest regions in the world, with actions maximizing forest cover on soils with marginal agricultural potential ...while concurrently increasing livelihoods and mitigating climate change. Based on satellite observations, here we show that diverse land use changes in southern China have increased standing aboveground carbon stocks by 0.11 ± 0.05 Pg C y
during 2002-2017. Most of this regional carbon sink was contributed by newly established forests (32%), while forests already existing contributed 24%. Forest growth in harvested forest areas contributed 16% and non-forest areas contributed 28% to the carbon sink, while timber harvest was tripled. Soil moisture declined significantly in 8% of the area. We demonstrate that land management in southern China has been removing an amount of carbon equivalent to 33% of regional fossil CO
emissions during the last 6 years, but forest growth saturation, land competition for food production and soil-water depletion challenge the longevity of this carbon sink service.
The wealth of complementary data available from remote sensing missions can hugely aid efforts towards accurately determining land use and quantifying subtle changes in land use management or ...intensity. This study reviewed 112 studies on fusing optical and radar data, which offer unique spectral and structural information, for land cover and use assessments. Contrary to our expectations, only 50 studies specifically addressed land use, and five assessed land use changes, while the majority addressed land cover. The advantages of fusion for land use analysis were assessed in 32 studies, and a large majority (28 studies) concluded that fusion improved results compared to using single data sources. Study sites were small, frequently 300–3000 km 2 or individual plots, with a lack of comparison of results and accuracies across sites. Although a variety of fusion techniques were used, pre-classification fusion followed by pixel-level inputs in traditional classification algorithms (e.g., Gaussian maximum likelihood classification) was common, but often without a concrete rationale on the applicability of the method to the land use theme being studied. Progress in this field of research requires the development of robust techniques of fusion to map the intricacies of land uses and changes therein and systematic procedures to assess the benefits of fusion over larger spatial scales.
Aim
The establishment of protected areas is among the most widespread responses to mitigate species loss. Although protected areas are often assumed to have conservation benefits, negative impacts ...have also been documented. One potential negative outcome is leakage, whereby protected areas displace land‐use activities harmful to conservation into adjacent areas. This can undermine protection by accelerating loss of species or skewing judgements of effectiveness. This study assessed the prevalence of deforestation leakage in a pan‐tropical and subtropical selection of 120 protected areas.
Location
Tropical and subtropical forest regions of America, Africa and Asia.
Time period
2001–2017.
Major taxa studied
Threatened species of amphibians, birds and terrestrial mammals.
Methods
We used Global Forest Change data to assess the average yearly rate of deforestation in protected areas, protected area buffer zones and statistically matched, unprotected control areas. We calculated and compared irreplaceability of habitat for threatened amphibian, bird and terrestrial mammal species between protected areas and buffer zones.
Results
In 55 cases, deforestation rates were higher in buffer zones than in protected and control areas, suggesting a relatively high prevalence of deforestation leakage stemming from protected areas. In 78.2% of documented leakage cases, reduced deforestation in protected areas was not sufficient to offset the amount of deforestation in 10 km buffer zones to a level that would be expected without protection. In 90.9% of leakage cases, the irreplaceability of species in the 10 km buffer zone was greater than that of the protected area, implying a negative impact of leakage on threatened species.
Main conclusions
The results suggest that protected areas are generally effective at preventing deforestation within their jurisdiction; however, leakage patterns can undermine conservation success because buffer zones often contain habitat for threatened species. We recommend accounting for the possibility of leakage when designing new protected areas and networks.
Assessments of land-system change have dominantly focused on conversions among broad land-use categories, whereas intensity changes within these categories have received less attention. Considering ...that both modes of land change typically result in diverse patterns and trajectories of land-system change, there is a need to develop approaches to reduce this complexity. Using Europe as a case study, we applied a clustering approach based on self-organising maps and 12 land-use indicators to map (1) land-system archetypes for the year 2006, defined as characteristic patterns of land-use extent and intensity, and (2) archetypical change trajectories, defined as characteristic changes in these indicators between 1990 and 2006. Our analysis identified 15 land-system archetypes, with low-intensity archetypes dominating (ca. 55 % coverage) followed by high-intensity archetypes (ca. 26 %). In terms of change, we identified 17 archetypical change trajectories, clustered in four broad categories. Stable land systems were most widespread (ca. 40 % of the EU27), followed by land systems characterised by land-use conversions (ca. 26 %), de-intensification trends (ca. 18 %), and intensification trends (ca. 15 %). Intensively used and intensifying land systems were particularly widespread in Western Europe, whereas low-intensity and de-intensifying land systems dominated in Europe’s east. Comparing our archetypes with environmental and socio-economic factors revealed that good accessibility and favourable topographic, climatic, and soil conditions characterised intensively managed areas. Intensification was also most common in these areas, suggesting an ongoing polarisation of intensification in favourable areas and de-intensification and abandonment trends in more marginal areas. By providing spatially and thematically improved maps of land-use patterns and changes therein, our archetypes could serve as useful inputs for more detailed assessments of ecosystem service demand and supply, as well as explorations of land-system change trade-offs, especially with regard to land-use intensity. Further, they could serve useful for identifying regions within which similar policy tools could be valuable to develop regionalised, context-specific land-management policies to steer European land systems onto desired pathways.
Above‐ground vegetation biomass is one of the major carbon sinks and provides both provisioning (e.g., forestry products) and regulating ecosystem services (by sequestering carbon). Continuing ...deforestation and climate change threaten this natural resource but can effectively be countered by national conservation policies. Here we present time series (1999–2017) derived from complementary satellite systems to describe a phenomenon of global significance: the greening of South China Karst. We find a major increase in growing season vegetation cover from 69% in 1999 to 81% in 2017 occurring over ~1.4 million km2. Over 1999–2012, we report one of the globally largest increases in biomass to occur in the South China Karst region (on average +4% over 0.9 million km2), which accounts for ~5% of the global areas characterized with increases in biomass. These increases in southern China's vegetation have occurred despite a decline in rainfall (−8%) and soil moisture (−5%) between 1999 and 2012 and are derived from effects of forestry and conservation activities at an unprecedented spatial scale in human history (~20,000 km2 yr−1 since 2002). These findings have major implications for the provisioning of ecosystem services not only for the Chinese karst ecosystem (e.g., carbon storage, water filtration, and timber production) but also for the study of global carbon cycles.
Key Points
We find one of the globally largest increases in vegetation cover and above‐ground biomass to occur in South China Karst
We apply a new Earth observation system based on low frequency passive microwaves to monitor biomass dynamics
The increase in vegetation cover (69% in 1999; 81% in 2017) occurs over ~1.4 million km2 and has been generated by widespread conservation efforts
Secure land access is vital for Myanmar's upland households, who rely on crops and forests to meet their subsistence needs. But recent land reforms threaten to undermine customary tenure and land-use ...practices in Myanmar. This paper combines income accounting methods with access theory to assess how new legislation may affect four Chin communities in the country's north-west. Our assessment of 94 households' land-access mechanisms and economic benefits from different types of land reveals existing land-access inequalities among Chin households and demonstrates communities' continued dependence on environmental resources, especially those from swidden fields, home gardens and forests. A majority of households would lose all of their land-derived income, if they were denied access to communities' customarily governed land, e.g., under the Vacant, Fallow and Virgin Land Management Law. Policy stakeholders should therefore intervene, to alleviate land-access inequalities among Chin households and to direct Myanmar's land-system dynamics onto more just development trajectories.
Livelihoods and agrarian change processes across upland South-East Asia have been explored for decades. Yet, knowledge gaps remain about contemporary livelihood strategies and land dependence in ...areas previously inaccessible to academic research, such as in upland Myanmar. Moreover, new strands of inquiry arise with continued globalisation, e.g., into the effects of remittances and labour migration on household incomes and livelihoods in distant upland areas. This study applied clustering techniques to income accounts of 94 households from northern Chin State, Myanmar to: (i) Identify households’ livelihood strategies; (ii) assess their dependence on access to land and natural resources; and (iii) compare absolute and relative incomes across strategies. We show that households engaged in six relatively distinct livelihood strategies: Relying primarily on own farming activities; making a living off the land with mixed income from agriculture and forest resources; engaging in wage employment; living from remittances; practicing non-forest tree husbandry; or engaging in self-employed business activities. We found significant income inequalities across clusters, with households engaging in remittance and wage-oriented livelihood strategies realizing higher incomes than those primarily involved in land-based activities. Our findings point to differentiated vulnerabilities associated with the identified livelihood strategies—to climate risks, shifting land-governance regimes and labour market forces.
Historic land-use and land-cover data are important inputs for assessing the impacts of human activity on the environment. Our goal was to reconstruct land-cover change from 1770 to 2010 and to ...evaluate its spatial determinants and underlying drivers for three study sites in diverse agroecological settings in Ryazan province in European Russia. We used historic maps and statistics as well as satellite imagery to reconstruct land-cover change and categorize it into six distinct land-management regimes. We applied spatially-explicit logistic regressions to assess which spatial determinants have had the strongest influences on land cover and how these influences have changed over time. Our results show how long-term land-cover trajectories can be modulated by broad political and economic alterations, rather than through gradual and local demand-side pressures from a rising population density and an increasing local demand for agricultural commodities.
It is often asserted that secondary forests (SF) provide inferior forest-based ecosystem services (ES), but there is limited research to generalize this claim. Here, we review comparisons between ES ...provision in SFs and other land uses in shifting cultivation landscapes. We searched the peer-reviewed literature and selected only studies that compare ES from SF with ES from other land uses. In total, 212 ES and 347 comparisons of different land use systems were recorded. Comparisons were mainly made for carbon storage, biodiversity, and soil variables. Very few provisioning ES were compared in the literature and no cultural services were recorded. SF were in most cases inferior to old-growth forest in terms of carbon storage and biodiversity, whereas soil quality comparisons varied. ES provision in SF was superior to agricultural systems, whereas comparisons with plantation crops varied. We conclude that the narrow focus on specific ES categories strongly limits understanding of SF in shifting cultivation areas and that it is more relevant to compare SFs with other agricultural systems rather than with old-growth forests.
Mainland Southeast Asia (MSA) has seen sweeping upland land use changes in the past decades, with transition from primarily subsistence shifting cultivation to annual commodity cropping. This ...transition holds implications for local upland communities and ecosystems. Due to its particular political regime, Myanmar is at the tail of this development. However, with Myanmar’s official strategy of agricultural commercialization and intensification, recent liberalization of the national economy, and influx of multinational agricultural companies, the effects on upland land transitions could come fast. We analyze the current state of upland land use in Myanmar in a socio-economic and political context, identify the dynamics in three indicator commodity crops (maize, cassava, and rubber), and discuss the state driven economic, tenurial and policy reforms that have occurred in upland areas of mainland Southeast Asian countries in past decades. We draw on these insights to contextualize our study and hypothesize about possible transition pathways for Myanmar. The transition to annual commodity cropping is generally driven by a range of socio-economic and technical factors. We find that land use dynamics for the three indicator crops are associated with market demand and thus the opening of national Southeast-Asian economies, research and development of locally suitable high yielding varieties (HYVs), and subsidies for the promotion of seeds and inputs. In contrast, promotion of HYVs in marginal areas and without adequate agricultural extension services may results in agricultural contraction and yield dis-intensification. The environmental impacts of the transition depend on the transition pathway, e.g., through large-scale plantation projects or smallholder initiatives. The agricultural development in upland MSA follows a clear diffusion pattern with transition occurring first in Thailand, spreading to Vietnam, Cambodia and Laos. While these countries point to prospects for Myanmar, we hypothesize that changes will come slow due to Myanmar’s sparse rural infrastructure, with uncertainty about tenure, in particular in areas still troubled by armed conflicts, and unwillingness of international investors to approach Myanmar given the recent setbacks to the democratization process.
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