scholarly journals Assessment of Land Productivity Dynamics in Relation to Land Degradation Using NDVI in Egypt

2020 ◽  
Vol 11 (9) ◽  
pp. 477-481
Author(s):  
T. M. H. Yossif
2019 ◽  
Author(s):  
Begoña de la Fuente ◽  
Mélanie Weynants ◽  
Bastian Bertzky ◽  
Giacomo Delli ◽  
Andrea Mandrici ◽  
...  

AbstractTracking changes in total biomass production or land productivity is an essential part of monitoring land transformations and long-term alterations of the health and productive capacity of land that are typically associated with land degradation. Persistent declines in land productivity impact many terrestrial ecosystem services that form the basis for sustainable livelihoods of human communities. Protected areas (PAs) are a key strategy in global efforts to conserve biodiversity and ecosystem services that are critical for human well-being, and cover about 15% of the land worldwide. Here we globally assess the trends in land productivity in PAs of at least 10 km2 and in their unprotected surroundings (10 km buffers) from 1999 to 2013. We quantify the percentage of the protected and unprotected land that shows stable, increasing or decreasing trends in land productivity, quantified as long-term (15 year) changes in above-ground biomass derived from satellite-based observations with a spatial resolution of 1 km. We find that 44% of the land in PAs globally has retained the productivity at stable levels from 1999 to 2013, compared to 42% of stable productivity in the unprotected land around PAs. Persistent increases in productivity are more common in the unprotected lands around PAs (32%) than within PAs (18%) globally, which may be related to more active management and vegetation cover changes in some of these unprotected lands. About 14% of the protected land and 12% of the unprotected land around PAs has experienced declines in land productivity from 1999 to 2013 globally. Oceania has the highest percentage of land with stable productivity in PAs (57%) followed by Asia (52%). Europe is the continent with the lowest percentage of land with stable productivity levels in PAs (38%) and with the largest share of protected land with increasing land productivity (32%), which may be related to the high population density and share of agricultural land within PAs as well as to rural land abandonment processes in many regions of Europe. In conclusion, we provide a relevant indicator and assessment of land productivity dynamics that contributes to characterise the state, pressures and changes in and around protected areas globally. Further research may focus on more detailed analyses to disentangle the relative contribution of specific drivers (from climate change to land use change) and their interaction with land productivity dynamics and potential land degradation in different regions of the world.


Author(s):  
Dusko Mukaetov Mukaetov ◽  
Ivan Blinkov ◽  
Hristina Poposka

Land degradation neutrality (LDN) is defined as a "state whereby the amount and quality of land resources nec-essary to support ecosystem functions and services and enhance food security remain stable or increase within specified temporal and spatial scales and ecosystems". The baseline is expressed as the initial (t0) estimated value of each of the three indicators, used as proxies of land-based natural capital and the ecosystem services that flow from that land base: land cover/land use change, land productivity status and trends, soil organic carbon status and trends. The baseline of LDN was calculated with estimation of the average values across the 10 years baseline period of the following indica-tors: Land Cover/Land Cover change (LC/LCC), Land Productivity Dynamics (LPD) and Soil Organic Carbon (SOC). Three tier approaches for computation of the selected indicators were used: Tier 1: Global/regional Earth observation, geospatial information and modelling; Tier 2: National statistics (only for LC/LCC) and Tier 3: Field survey. Most sig-nificant changes in LC for the period 2000/2012 are in the categories of Forest land and Shrubs/grasslands. According the global data sets used for analysis of LPD, the total affected area with depletion of Land productivity for the period 2000/2010 is identified on a only 2.35 % of the country territory. The available global data sets gives a model SOC lev-els for the period 2000/2010. According these data, the total loss of SOC in our country is estimated on 3951 t.


2020 ◽  
Vol 32 (1) ◽  
pp. 49-65
Author(s):  
Frédérique Montfort ◽  
Agnès Bégué ◽  
Louise Leroux ◽  
Lilian Blanc ◽  
Valéry Gond ◽  
...  

2018 ◽  
Vol 8 (2) ◽  
pp. 20
Author(s):  
Tesfaye Samuel Saguye

Land degradation is increasing in severity and extent in many parts of the world. Success in arresting land degradation entails an improved understanding of its causes, process, indicators and impacts. Various scientific methodologies have been employed to assess land degradation globally. However, the use of local community knowledge in elucidating the causes, process, indicators and effects of land degradation has seen little application by scientists and policy makers. Land degradation may be a physical process, but its underlying causes are firmly rooted in the socio-economic, political and cultural environment in which land users operate. Analyzing the root causes and effects of land degradation from local community knowledge, perception and adapting strategies perspective will provide information that is essential for designing and promoting sustainable land management practices. The main objective of this study was to analyze the perceptions of farmers’ on the impact of land degradation hazard on agricultural land productivity decline associated with soil erosion and fertility loss. The study used a multistage sampling procedure to select sample respondent households. The sample size of the study was 120 household heads and 226 farm plots managed by these farmers. The primary data of the study were collected by using semi-structured Interview, focus group discussions and field observation. Both descriptive statistics and econometric techniques were used for data analysis. Descriptive results show that 57percent of the respondents were perceived the severity and its consequence on agricultural land productivity. The following indicators of soil erosion and fertility loss were generally perceived and observed by farmers’ in the study area: gullies formations, soil accumulation around clumps of vegetation, soil deposits on gentle slopes, exposed roots, muddy water, sedimentation in streams and rivers, change in vegetation species, increased runoff, and reduced rooting depth. The direct human activities which were perceived to be causing land degradation in the study area include: deforestation and clearing of vegetation, overgrazing, steep slope cultivation and continuous cropping. The farmers’ possibility of perceiving the impact of land degradation hazard on agricultural land productivity was primarily determined by institutional, psychological, demographic and by bio-physical factors. Farmers who perceive their land as deteriorating and producing less than desired, tend to adopt improved land management practices. On the other hand, farmers who perceive their land to be fertile tend to have low adoption of conservation practices. In order to overcome this land degradation and its consequent effects, the study recommended a need for the government to enforce effective policies to control and prevent land degradation and these policies should be community inclusive /participatory founded up on indigenous and age-honored knowledge and tradition of farmers' natural resource management as well as introduced scientific practices.


2019 ◽  
Vol 489 (2) ◽  
pp. 195-198
Author(s):  
A. V. Ptichnikov ◽  
D. V. Karelin ◽  
V. M. Kotlyakov ◽  
Y. A. Pautov ◽  
A. Y. Borovlev ◽  
...  

In this paper, we analyze applicability of Land degradation neutrality (LDN) concept of the UN Convention to Combat Desertification for Russian boreal forests. In this regard, it is necessary to adapt the three global LDN indicators (land cover, land productivity, and carbon stocks) to the assessment of land degradation processes of boreal forests in Russia and around the world. The proposed study concludes that landscapes with different types of forest restoration dynamics can be viewed as the object in forest land dynamic studies. The proposed research also suggests the set of LDN indicators adapted for boreal forests conditions. In order to assess LDN proxies we calculated the retrospective and projected net carbon balance in the middle taiga zone of Noshulskoye forest domain (Komi Republic, Russia) using the CBM CFS model. Here we explored 3 scenarios of forest net carbon balance under the three different felling regimes. It was shown that the net carbon balance cannot be applied as an independent LDN indicator, since it does not take into account changes in species diversity and primary productivity. We also suggest that industrial felling should imitate natural types of restoration dynamics in order to achieve LDN targets. It can be reached through minimization of forest felling at sites with fireless types of succession, which accumulate maximum stocks of dead phytomass matter and serve as forest refuges supporting biodiversity.


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